Brake control device

The present invention relates to a brake control device that controls a braking force applied to the wheels of a vehicle.

For example, Patent Document 1 describes a brake control device that controls the braking force by increasing the degree of freedom of hydraulic pressure control in the wheel cylinders of four wheels according to the situation. This device includes a power hydraulic pressure source that can accumulate pressure with the hydraulic fluid using power and a manual hydraulic pressure source that pressurizes the hydraulic fluid according to the amount of brake operation by the driver. The hydraulic pressure of the wheel cylinder can be controlled. The power hydraulic pressure source is connected to a hydraulic path that commonly controls the left front wheel, right front wheel, left rear wheel, and right rear wheel, and controls to pressurize the wheel cylinders of the four wheels during normal control.

On the other hand, the manual hydraulic pressure source is connected to a hydraulic path for the front wheels that controls the left front wheel and the right front wheel and a hydraulic path for the rear wheels that controls the left rear wheel and the right rear wheel. It also has a separation valve that allows the path to the left front wheel and the right front wheel to be separated from the path to the left rear wheel and the right rear wheel. For example, if a liquid leak occurs in any of the hydraulic flow paths connected to each wheel cylinder and the pressure control from the power hydraulic pressure source cannot be performed well, the hydraulic pressure control by the manual hydraulic pressure source is switched to. , The hydraulic flow path for front wheels or rear wheels, which includes the hydraulic flow path that caused liquid leakage, is separated from the manual hydraulic pressure source by closing the separation valve, and only the flow path for front wheels or the flow for rear wheels. Braking only on the road. In this way, by making the braking force control separable into the control system for the front wheels and the control system for the rear wheels, it is possible to secure the braking force only on the front wheels or the braking force only on the rear wheels. , The vehicle can be braked even if one of the flow path systems has a problem.

Similarly, Patent Document 2 discloses a braking control device having a power hydraulic pressure source and a manual hydraulic pressure source. Also in this device, the hydraulic flow path for the front wheels and the hydraulic flow path for the rear wheels are connected to the manual hydraulic pressure source, and the manual hydraulic pressure source enables braking control by only the front wheels or only the rear wheels.

<p num="0005"><patcit num="1"><text>JP-A-2007-203859</text></patcit><patcit num="2"><text>Japanese Unexamined Patent Publication No. 2002-187537</text></patcit></p>

<p num="0006"> By the way, since the front wheel side of the vehicle is equipped with heavy parts such as a power source, a transmission, and a steering device, a braking device having a larger braking ability than that of the rear wheel side is mounted. In other words, on the rear wheel side compared to the front wheel side, an inexpensive braking device having a small braking ability and a small braking device could be used. However, as in Patent Document 1 and Patent Document 2 described above, when the braking force is secured only by the front wheels or the braking force is secured only by the rear wheels by controlling the braking force by the hydraulic fluid from the manual hydraulic pressure source, the braking force is secured only on the front wheels side. It is necessary to be able to secure the braking force stipulated by law in both the case of braking and the case of braking only on the rear wheel side. That is, it is necessary to install a brake device on the rear wheel side having the same braking ability as that on the front wheel side. As a result, there arises a problem that the restrictions on the weight distribution of the vehicle and the restrictions on the capacity of the brake device for the rear wheels become strict. Further, it is necessary to use a disc brake device having a large braking ability as a brake device for the rear wheels, which has a problem that cost reduction and weight reduction are hindered.</p><p num="0007"> Therefore, the present invention provides a power hydraulic pressure source and a manual hydraulic pressure source, and provides a brake feeling even when a brake device having different braking capacities on the rear wheel side and the front wheel side is mounted for cost reduction and miniaturization. It is an object of the present invention to provide a brake control device capable of exerting a sufficient braking force without causing a decrease.</p>

<p num="0008"> The brake control device of an aspect of the present invention uses a manual hydraulic pressure source that pressurizes the stored hydraulic fluid according to the amount of brake operation by the driver, and a pressure accumulating by the hydraulic fluid using a power independent of the driver's brake operation. A power hydraulic pressure source capable of this, a liquid amount control valve that controls the amount of hydraulic liquid supplied from the power hydraulic pressure source to the wheel cylinder side of each wheel, and a hydraulic liquid from the manual hydraulic pressure source on the left. A first flow path that can supply the front wheel cylinder and the right rear wheel wheel cylinder, and a second flow path that can supply the hydraulic fluid from the manual hydraulic pressure source to the right front wheel wheel cylinder and the left rear wheel wheel cylinder. When the separating valve that can be separated into the wheel and the hydraulic fluid that passes through the liquid amount control valve are supplied to the wheel cylinders from the first flow path and the second flow path, the working fluid causes the separation valve. The hydraulic fluid is supplied so as to reduce the state difference between the hydraulic fluid supply state of either the first flow path or the second flow path that flows in through the separation valve and the other hydraulic fluid supply state that does not pass through the separation valve. Includes an adjustment unit that adjusts the state.</p><p num="0009"> According to this aspect, the first flow path brakes the left front wheel and the right rear wheel, and the second flow path brakes the right front wheel and the left rear wheel. Therefore, even if a problem occurs in one of the flow paths and braking control is performed only in the other flow path, both the brake device for the front wheels and the brake device for the rear wheels can be used. As a result, even if different braking performance brake devices are used for the front wheels and the rear wheels, the same braking feeling is sufficient when braking using the first flow path and when braking using the second flow path. Braking force can be obtained. Further, when the hydraulic fluid passing through the liquid amount control valve is supplied to both the first flow path and the second flow path separated by the presence of the separation valve, the separation valve is connected in the first flow path and the second flow path. The hydraulic fluid supply state on the passing side and the non-passing side can be adjusted so that the difference in state is reduced by the action of the adjusting unit. Here, the working liquid supply state is a concept including a state when the working liquid is supplied, such as the flow rate and pressure of the working liquid and the timing of supply. As a result, it is possible to suppress the occurrence of differential pressure and response difference between the flow path passing through the separation valve and the flow path not passing through, so that balanced braking can be realized on the front, rear, left and right wheels. That is, even when a brake device having different braking capabilities is mounted on the rear wheel side and the front wheel side, a sufficient braking force can be exerted without causing a deterioration in the brake feeling.</p><p num="0010"> Further, in the above aspect, a plurality of on-off valves provided for each of the wheel cylinders to determine whether or not to supply the hydraulic fluid to the wheel cylinders, and a valve for controlling the liquid amount control valve and the on-off state of the on-off valve. The valve control unit may not change the control state of the liquid amount control valve for a predetermined time when switching the open / closed state of the on-off valve, further including a control unit. By switching the open / closed state of the on-off valve, the flow pressure of the working fluid changes abruptly, and a flow pressure that temporarily swings up and down with respect to the target flow pressure of the liquid amount control valve is generated. If the valve control unit controls the liquid amount control valve following this temporary change in flow pressure, the control becomes excessive and causes vibration and abnormal noise. Therefore, the valve control unit does not temporarily change the control state of the liquid amount control valve when switching the open / closed state of the on-off valve. That is, the valve control unit changes the control state of the liquid amount control valve after the open / closed state of the on-off valve is switched and the flow pressure stabilizes after a lapse of a predetermined time. As a result, excessive opening / closing control when the opening / closing state is switched is suppressed, and accordingly, vibration and abnormal noise during operation of the liquid amount control valve can be suppressed.</p><p num="0011"> Further, in the above aspect, a plurality of on-off valves provided for each wheel cylinder to determine whether or not to supply the hydraulic fluid to the wheel cylinders, and a valve for controlling the liquid amount control valve and the on-off state of the on-off valve. The valve control unit further includes a control unit, and the valve control unit controls at least the opening / closing valve when the hydraulic fluid via the liquid amount control valve is supplied to each wheel cylinder side. When switching the open / closed state of the valve, the liquid amount control valve may be controlled by a control gain corresponding to the number of open / close valves that are switched at the same time. According to this aspect, the control gain is determined in consideration of the fluctuation of the flow pressure of the hydraulic fluid based on the number of on-off valves whose open / closed states have been switched. Since a control gain suitable for fluctuations in the flow pressure is used, it is possible to suppress the generation of vibration and abnormal noise caused by the fluctuations in the flow pressure. For the control gain, the correspondence between the number of on-off valves whose open / closed state has been switched and the change in flow pressure generated at that time is acquired in advance by a test or the like, and vibration or abnormal noise due to the change in flow pressure is obtained. It is preferable to determine the optimum value that can suppress the occurrence of.</p><p num="0012"> Further, in the above embodiment, a plurality of on-off valves provided for each wheel cylinder to determine whether or not to supply the hydraulic fluid to the wheel cylinder, and the manual hydraulic pressure source are formed and supplied from the power hydraulic pressure source. A regulator that adjusts the hydraulic pressure of the hydraulic fluid to be operated according to the amount of brake operation by the driver, a regulator flow path that connects the region between the separation valve and the adjusting portion, and the regulator, and the liquid amount control valve. Further includes a valve control unit that controls the open / closed state of the on-off valve, and when the valve control unit controls each on-off valve individually, the valve control unit controls the regulator from the hydraulic fluid supply via the liquid amount control valve. It may be switched to the hydraulic fluid supply via. For example, in the case of anti-lock brake control (ABS control), each on-off valve is not a detailed hydraulic pressure control using a liquid amount control valve, but a regulator pressure is supplied to each control valve from a regulator and only the on-off valve is opened and closed. It can be performed by hydraulic pressure control. As a result, the operation of the liquid amount control valve can be omitted during ABS control, and the frequency of use can be reduced, which can contribute to the extension of the life of the liquid amount control valve.</p><p num="0013"> Further, the brake control device according to an aspect of the present invention uses a power hydraulic pressure source capable of accumulating pressure by a hydraulic fluid using a power independent of the driver's brake operation, and a driver's brake operating amount using the stored hydraulic fluid. A manual hydraulic pressure source that pressurizes according to the power hydraulic pressure source, a regulator that adjusts the hydraulic pressure of the hydraulic fluid supplied from the power hydraulic pressure source according to the amount of brake operation by the driver, and wheels of each wheel from the power hydraulic pressure source. A shutoff valve that can shut off the flow path of the hydraulic fluid supplied to the cylinder side, a liquid amount control valve that controls the amount of the hydraulic fluid supplied from the regulator to each wheel cylinder side, and the manual hydraulic pressure source. The first flow path capable of supplying the hydraulic fluid from the left front wheel wheel cylinder and the right rear wheel wheel cylinder, and the hydraulic fluid from the manual hydraulic pressure source are supplied to the right front wheel wheel cylinder and the left rear wheel wheel cylinder. When a separation valve that can be separated into a possible second flow path and a hydraulic fluid that passes through the liquid amount control valve are supplied from the first flow path or the second flow path to each wheel cylinder side, or the said. When the hydraulic fluid via the shutoff valve is supplied from the first flow path or the second flow path to each wheel cylinder side, the hydraulic fluid flows into the first flow path or the separation valve. An adjusting unit that adjusts the hydraulic fluid supply state so that the state difference between the hydraulic fluid supply state of any of the second flow paths and the hydraulic fluid supply state that does not pass through the separation valve is reduced, and each of the valves. Includes a valve control unit that controls the opening and closing of the wheel.</p><p num="0014"> According to this aspect, the first flow path brakes the left front wheel and the right rear wheel, and the second flow path brakes the right front wheel and the left rear wheel. Therefore, even if a problem occurs in one of the flow paths and braking control is performed only in the other flow path, both the brake device for the front wheels and the brake device for the rear wheels can be used. As a result, even if different braking performance brake devices are used for the front wheels and the rear wheels, the same braking feeling is sufficient when braking using the first flow path and when braking using the second flow path. Braking force can be obtained. Further, the hydraulic pressure control valve is supplied with a hydraulic pressure adjusted to a hydraulic pressure smaller than the hydraulic pressure supplied from the power hydraulic pressure source by the regulator, and can be supplied to each on-off valve, so that the load on the hydraulic pressure control valve can be supplied. Can be reduced, which can contribute to the extension of the life of the hydraulic pressure control valve. Further, when the hydraulic fluid passing through the liquid amount control valve is supplied to both the first flow path and the second flow path separated by the presence of the separation valve, the separation valve is connected in the first flow path and the second flow path. The hydraulic fluid supply state on the passing side and the non-passing side can be adjusted so that the difference in state is reduced by the action of the adjusting unit. As a result, it is possible to suppress the occurrence of differential pressure and response difference between the flow path passing through the separation valve and the flow path not passing through, so that balanced braking can be realized on the front, rear, left and right wheels. That is, even when a brake device having different braking capabilities is mounted on the rear wheel side and the front wheel side, a sufficient braking force can be exerted without causing a deterioration in the brake feeling.</p><p num="0015"> Further, in the above aspect, the adjusting portion may be configured by an orifice. The flow resistance of the working fluid due to the throttle of the orifice can be the same as the flow resistance when passing through the separation valve. As a result, the structure can be simplified and the cost can be reduced as compared with the case where the adjusting unit is configured by the same mechanism as the separation valve. Further, since the orifice only changes the flow resistance by the throttle, its operation management becomes unnecessary.</p>

<p num="0016"> According to the present invention, a power hydraulic pressure source and a manual hydraulic pressure source are provided, and even when a brake device having different braking capacities on the rear wheel side and the front wheel side is mounted for cost reduction and miniaturization, the brake feeling is provided. Sufficient braking force can be exerted without causing a decrease.</p>

<figref num="1">It is a schematic block diagram which shows the vehicle to which the brake control device which concerns on one Embodiment of this invention is applied.</figref><figref num="2">It is a system diagram which shows the hydraulic brake unit which concerns on one Embodiment of this invention.</figref><figref num="3">It is explanatory drawing explaining the relationship between the operating state of the holding valve and the control gain of a liquid amount control valve in the brake control device which concerns on one Embodiment of this invention.</figref><figref num="4">It is explanatory drawing explaining the synchronization example of the ABS control mode and the control gain of a liquid amount control valve in the brake control device which concerns on one Embodiment of this invention.</figref><figref num="5">It is a flowchart explaining the control state of the pump which performs the pressure accumulation control of the power hydraulic pressure source in the brake control device which concerns on one Embodiment of this invention.</figref><figref num="6">It is a flowchart explaining the detail of the intermittent pump control mode processing of S104 of FIG.</figref><figref num="7">It is a system diagram which shows the hydraulic brake unit which concerns on other embodiment of this invention.</figref><figref num="8">It is a system diagram which shows the hydraulic brake unit which concerns on other embodiment of this invention.</figref><figref num="9">It is a partial system diagram which shows the modification of the adjustment part included in the hydraulic brake unit which concerns on one Embodiment of this invention.</figref>

The brake control device according to the embodiment of the present invention has a manual hydraulic pressure source and a power hydraulic pressure source as hydraulic pressure supply sources for supplying hydraulic pressure to each wheel. The manual hydraulic pressure source of this brake control device is the first flow path that supplies the hydraulic fluid to the wheel cylinders of the left front wheel and the right rear wheel, and the second flow path that supplies the hydraulic fluid to the wheel cylinders of the right front wheel and the left rear wheel. Is connected to a so-called "X-pipe" type hydraulic actuator to which is connected. By setting the two systems of piping from the manual hydraulic pressure source as "X piping" in this way, if a failure such as liquid leakage occurs in either the first flow path or the second flow path, The other flow path enables braking by one of the front wheel braking devices and the rear wheel braking device located diagonally thereof.

As a result, the brake device on the front wheel side and the brake device on the rear wheel side can be used regardless of which path of the two systems fails, and the brake device with different braking performance is used for the front wheel and the rear wheel. Even if it is, the same braking force can be obtained with either of the two systems. For example, a brake device having a smaller braking performance on the rear wheel side than the front wheel side can be used in response to the vehicle weight distribution, which can contribute to miniaturization and cost reduction of the brake device.

By the way, in the so-called electronically controlled brake system (ECB) in which the hydraulic fluid is supplied from the power hydraulic pressure source to each wheel cylinder via the fluid amount control valve based on the brake operation amount of the driver or based on the automatic control of the vehicle. When adopting "X piping" such as, there are items that need to be considered. That is, when the ECB is operating normally, it is necessary to form a main flow path for supplying the hydraulic fluid via the liquid amount control valve to the four wheels in the front, rear, left and right. On the other hand, as described above, it is necessary to provide a separation valve in the main flow path in order to separate the two flow paths in order to deal with the case where a failure occurs in the flow path. Therefore, when the hydraulic fluid that has passed through the liquid amount control valve is commonly supplied to the front, rear, left, and right four wheels, a flow path that passes through the separation valve and a flow path that does not pass through the separation valve are generated. As a result, a pressure difference may occur between the first flow path and the second flow path, or a difference in response time may occur.

Therefore, in one embodiment of the present invention, the working fluid supply state of either the first flow path or the second flow path through which the working fluid flows through the separation valve and the other working fluid supply that does not pass through the separation valve It is equipped with an adjusting unit that adjusts the working fluid supply state so that the state difference from the state is reduced. By providing the adjusting part, the brake feeling is improved by suppressing the pressure difference and the difference in response time between the first flow path and the second flow path.

FIG. 1 is a schematic configuration diagram showing a vehicle to which the brake control device according to the embodiment of the present invention is applied. The vehicle 1 shown in the figure is configured as a so-called hybrid vehicle, and includes an engine 2, a 3-axis type power split mechanism 3 connected to a crankshaft which is an output shaft of the engine 2, and a power split mechanism 3. A connected motor generator 4 capable of generating power, an electric motor 6 connected to the power split mechanism 3 via a transmission 5, and a hybrid electronic control unit that controls the entire drive system of the vehicle 1 (hereinafter, "hybrid ECU"). All electronic control units are referred to as "ECUs".) 7. The right front wheel 9FR and the left front wheel 9FL, which are the drive wheels of the vehicle 1, are connected to the transmission 5 via the drive shaft 8.

The engine 2 is an internal combustion engine operated by using a hydrocarbon fuel such as gasoline or light oil, and is controlled by the engine ECU 13. The engine ECU 13 can communicate with the hybrid ECU 7, and performs fuel injection control, ignition control, intake control, etc. of the engine 2 based on the control signal from the hybrid ECU 7 and the signals from various sensors that detect the operating state of the engine 2. Execute. In addition, the engine ECU 13 provides the hybrid ECU 7 with information on the operating state of the engine 2 as needed.

The power split mechanism 3 has a role of transmitting the output of the electric motor 6 to the left and right front wheels 9FR and 9FL via the transmission 5, a role of distributing the output of the engine 2 to the motor generator 4 and the transmission 5, and an electric motor. It plays a role of decelerating or increasing the rotation speed of 6 and engine 2. The motor generator 4 and the electric motor 6 are each connected to the battery 12 via a power converter 11 including an inverter, and the motor ECU 14 is connected to the power converter 11. As the battery 12, a storage battery such as a nickel-metal hydride storage battery can be used. The motor ECU 14 can also communicate with the hybrid ECU 7, and controls the motor generator 4 and the electric motor 6 via the power converter 11 based on a control signal or the like from the hybrid ECU 7. The hybrid ECU 7, engine ECU 13, and motor ECU 14 described above are all configured as microprocessors including a CPU, and in addition to the CPU, a ROM that stores various programs, a RAM that temporarily stores data, and an input / output port. And equipped with a communication port and the like.

By supplying electric power from the battery 12 to the electric motor 6 via the power converter 11 under the control of the hybrid ECU 7 and the motor ECU 14, the left and right front wheels 9FR and 9FL can be driven by the output of the electric motor 6. .. Further, in the driving region where the engine efficiency is high, the vehicle 1 is driven by the engine 2. At this time, by transmitting a part of the output of the engine 2 to the motor generator 4 via the power split mechanism 3, the electric power generated by the motor generator 4 is used to drive the electric motor 6 or to drive the power converter 11. It becomes possible to charge the battery 12 through the system.

When braking the vehicle 1, the electric motor 6 is rotated by the power transmitted from the front wheels 9FR and 9FL under the control of the hybrid ECU 7 and the motor ECU 14, and the electric motor 6 is operated as a generator. That is, the electric motor 6, the power converter 11, the hybrid ECU 7, the motor ECU 14, and the like function as a regenerative braking unit 10 that applies braking force to the left and right front wheels 9FR and 9FL by regenerating the kinetic energy of the vehicle 1 into electric energy. To do.

In the brake control device according to one embodiment, the braking force required by executing the brake regenerative cooperative control in which the regenerative braking force and the friction braking force are used in combination is generated. The regenerative braking force is a braking force applied to the wheels by operating the electric motor for driving the wheels as a generator that receives the rotational torque of the running wheels as an input. The kinetic energy of the vehicle is converted into electric energy, and the electric energy is stored in the storage battery from the electric motor via a power conversion device including an inverter or the like. The stored electric energy will be used for driving the wheels and the like thereafter, and will contribute to improving the fuel efficiency of the vehicle. On the other hand, the friction braking force is a braking force applied to the wheel by pressing the friction member against the rotating member rotating together with the wheel. In the following, as an example of the friction braking force, the hydraulic braking force in which the friction member is pressed against the rotating member by the supply of the brake fluid as the hydraulic fluid from the hydraulic pressure source will be described. In order to further improve fuel efficiency, it is preferable that the regenerative braking force is preferentially used, and the amount that the regenerative braking force alone is insufficient for the required braking force is complementarily generated by the hydraulic braking force.

In addition to the regenerative brake unit 10, the vehicle 1 includes a hydraulic brake unit 20 that generates braking force by supplying brake fluid from a power hydraulic pressure source 30 or the like, as shown in FIG. The vehicle 1 can generate a desired braking force by using the regenerative braking force and the hydraulic braking force in combination by executing the brake regeneration cooperative control.

FIG. 2 is a system diagram showing the hydraulic brake unit 20 according to the present embodiment. As shown in FIG. 2, the hydraulic brake unit 20 includes disc brake units 21FR, 21FL, 21RR and 21RL provided corresponding to each wheel, a master cylinder unit 27, a power hydraulic pressure source 30, and a liquid. Includes with pressure actuator 40.

The disc brake units 21FR, 21FL, 21RR and 21RL apply braking force to the right front wheel, left front wheel, right rear wheel, and left rear wheel of the vehicle, respectively. The master cylinder unit 27 as the manual hydraulic pressure source in the present embodiment sends the brake fluid pressurized according to the amount of operation by the driver of the brake pedal 24 as the brake operating member to the disc brake units 21FR to 21RL. To do. The power hydraulic pressure source 30 can send the brake fluid pressurized by the supply of power to the disc brake units 21FR to 21RL independently of the operation of the brake pedal 24 by the driver. The hydraulic actuator 40 appropriately adjusts the hydraulic pressure of the brake fluid supplied from the power hydraulic pressure source 30 or the master cylinder unit 27 and sends it to the disc brake units 21FR to 21RL. As a result, the braking force for each wheel due to hydraulic braking is adjusted.

Each of the disc brake units 21FR to 21RL, the master cylinder unit 27, the power hydraulic pressure source 30, and the hydraulic actuator 40 will be described in more detail below. Each disc brake unit 21FR to 21RL includes a brake disc 22 and wheel cylinders 23FR to 23RL built into the brake caliper, respectively. The wheel cylinders 23FR to 23RL are connected to the hydraulic actuator 40 via different fluid passages. In the following, the wheel cylinders 23FR to 23RL will be collectively referred to as "wheel cylinder 23" as appropriate.

In the disc brake units 21FR to 21RL, when the brake fluid is supplied from the hydraulic actuator 40 to the wheel cylinder 23, the brake pad as a friction member is pressed against the brake disc 22 rotating together with the wheels. As a result, braking force is applied to each wheel. Although the disc brake units 21FR to 21RL are used in this embodiment, other braking force applying mechanisms including the wheel cylinder 23 such as a drum brake may be used.

In the present embodiment, the master cylinder unit 27 is a type with a hydraulic booster in which the master cylinder is composed of two chambers, and is a hydraulic booster 31a, a regulator 31, a first master cylinder 32, a second master cylinder 33, and Includes reservoir 34. The hydraulic booster 31a communicates with the regulator 31 into which the high pressure brake fluid from the power hydraulic source 30 is introduced. The hydraulic booster 31a is connected to the brake pedal 24, and amplifies the pedal depression force applied to the brake pedal 24 and transmits it to the first master cylinder 32 and the second master cylinder 33. That is, the pedal pedal force is amplified by supplying the brake fluid from the power hydraulic pressure source 30 to the hydraulic booster 31a via the regulator 31. Then, the first master cylinder 32 and the second master cylinder 33 generate substantially the same master cylinder pressure having a predetermined boosting ratio with respect to the pedal depression force.

A reservoir 34 for storing brake fluid is arranged above the first master cylinder 32, the second master cylinder 33, and the regulator 31. The first master cylinder 32 and the second master cylinder 33 communicate with the reservoir 34 when the brake pedal 24 is released. On the other hand, the regulator 31 communicates with both the reservoir 34 and the accumulator 35 of the power hydraulic pressure source 30, and uses the reservoir 34 as a low-pressure source and the accumulator 35 as a high-pressure source, and the hydraulic pressure is almost equal to the master cylinder pressure. Occurs. The hydraulic pressure in the regulator 31 is appropriately referred to as "regulator pressure" below. The master cylinder pressure and the regulator pressure do not have to be exactly the same, and for example, the master cylinder unit 27 can be designed so that the regulator pressure is slightly higher.

The power hydraulic pressure source 30 includes an accumulator 35 and a pump 36. The accumulator 35 converts the pressure energy of the brake fluid boosted by the pump 36 into the pressure energy of an enclosed gas such as nitrogen, for example, about 14 to 22 MPa and stores it. The pump 36 has a motor 36a as a drive source, the suction port of which is connected to the reservoir 34, and the discharge port of which is connected to the accumulator 35. The accumulator 35 is also connected to the relief valve 35a provided in the master cylinder unit 27. When the pressure of the brake fluid in the accumulator 35 rises abnormally to, for example, about 25 MPa, the relief valve 35a opens and the high-pressure brake fluid is returned to the reservoir 34.

As described above, the hydraulic brake unit 20 has a first master cylinder 32, a second master cylinder 33, and an accumulator 35 as a source of brake fluid for the wheel cylinder 23. The first master pipe 37 is connected to the first master cylinder 32, the second master pipe 38 is connected to the second master cylinder 33, and the accumulator pipe 39 is connected to the accumulator 35. The first master pipe 37, the second master pipe 38, and the accumulator pipe 39 are each connected to the hydraulic actuator 40.

The hydraulic actuator 40 includes an actuator block in which a plurality of flow paths are formed and a plurality of electromagnetic control valves. The flow paths formed in the actuator block include individual flow paths 41, 42, 43 and 44, and a main flow path 45. The individual flow paths 41 to 44 are branched from the main flow path 45, respectively, and are connected to the wheel cylinders 23FR, 23FL, 23RR, 23RL of the corresponding disc brake units 21FR, 21FL, 21RR, 21RL. As a result, each wheel cylinder 23 can communicate with the main flow path 45.

Further, ABS holding valves 51, 52, 53 and 54, which are on-off valves, are provided in the middle of the individual flow paths 41, 42, 43 and 44. Each ABS holding valve 51 to 54 has a solenoid and a spring that are ON / OFF controlled, and both are normally open electromagnetic control valves that are opened when the solenoid is in a non-energized state. The ABS holding valves 51 to 54 in the open state can distribute the brake fluid in both directions. That is, the brake fluid can be flowed from the main flow path 45 to the wheel cylinder 23, and conversely, the brake fluid can be flowed from the wheel cylinder 23 to the main flow path 45 as well. When the solenoid is energized and the ABS holding valves 51 to 54 are closed, the flow of brake fluid in the individual flow paths 41 to 44 is cut off.

Further, the wheel cylinder 23 is connected to the reservoir flow path 55 via the decompression flow paths 46, 47, 48 and 49, which are connected to the individual flow paths 41 to 44, respectively. ABS pressure reducing valves 56, 57, 58 and 59, which are on-off valves, are provided in the middle of the pressure reducing channels 46, 47, 48 and 49. Each ABS pressure reducing valve 56 to 59 has a solenoid and a spring that are ON / OFF controlled, and both are normally closed electromagnetic control valves that are closed when the solenoid is in a non-energized state. When the ABS pressure reducing valves 56 to 59 are closed, the flow of brake fluid in the pressure reducing flow paths 46 to 49 is cut off. When the solenoid is energized and each ABS pressure reducing valve 56 to 59 is opened, the flow of brake fluid in the pressure reducing flow path 46 to 49 is permitted, and the brake fluid is released from the wheel cylinder 23 to the pressure reducing flow path 46 to 49 and. It returns to the reservoir 34 via the reservoir flow path 55. The reservoir flow path 55 is connected to the reservoir 34 of the master cylinder unit 27 via the reservoir pipe 77.

The main flow path 45 has a separation valve 60 in the middle. The separation valve 60 divides the main flow path 45 into a first flow path 45a connected to the individual flow paths 41 and 42 and a second flow path 45b connected to the individual flow paths 43 and 44. The first flow path 45a is connected to the wheel cylinder 23RL for the left rear wheel and the wheel cylinder 23FR for the right front wheel via the individual flow paths 41 and 42, and the second flow path 45b connects the individual flow paths 43 and 44. It is connected to the wheel cylinder 23FL for the left front wheel and the wheel cylinder 23RL for the right rear wheel via. In other words, the two flow paths are connected by so-called "X pipes", which are connected to the four wheel cylinders 23 on the front, back, left and right. The features of "X piping" will be described later.

The separation valve 60 has a solenoid and a spring that are ON / OFF controlled, and is a normally closed electromagnetic control valve that is closed when the solenoid is in a non-energized state. When the separation valve 60 is closed, the flow of brake fluid in the main flow path 45 is cut off. When the solenoid is energized and the separation valve 60 is opened, the brake fluid can be circulated in both directions between the first flow path 45a and the second flow path 45b.

Further, one of the first flow path 45a and the second flow path 45b separated by the separation valve 60 is provided with an adjusting portion which is a characteristic configuration of the hydraulic actuator 40 of the present embodiment. In the case of FIG. 2, the adjusting unit is provided in the second flow path 45b and has a function of giving a predetermined flow resistance to the second flow path 45b to adjust the flow rate. In the case of FIG. 2, an example in which the adjusting portion is composed of the orifice 100 is shown. The orifice 100 has substantially the same flow resistance when the brake fluid passes through the orifice 100 and when the brake fluid passes through the separation valve 60 when the separation valve 60 is open. The cross-sectional area is adjusted so as to. Details of the effect of the arrangement of the orifice 100 will be described later. As shown in FIG. 2, the valve opening direction of the separation valve 60 has a structure that facilitates the introduction of brake fluid from the booster linear control valve 66, which will be described later. With this configuration, it is possible to prevent a decrease in the responsiveness of the wheel cylinder 23 due to a delay in opening the valve during valve opening.

In the hydraulic actuator 40, a first master flow path 61 and a second master flow path 62 communicating with the main flow path 45 are formed. More specifically, the first master flow path 61 is connected to the first flow path 45a of the main flow path 45, and the second master flow path 62 is connected to the second flow path 45b of the main flow path 45. .. Further, the first master flow path 61 is connected to the first master pipe 37 that communicates with the first master cylinder 32. The second master flow path 62 is connected to the second master pipe 38 that communicates with the second master cylinder 33.

The first master flow path 61 has a first master cut valve 64 in the middle. The first master cut valve 64 is provided on the brake fluid supply path from the first master cylinder 32 to each wheel cylinder 23. The first master cut valve 64 has a solenoid and a spring that are ON / OFF controlled, and the valve closed state is guaranteed by the electromagnetic force generated by the solenoid when the specified control current is supplied, and the solenoid is not energized. It is a normally open type electromagnetic control valve that is opened when it is in a state. The first master cut valve 64 in the open state can circulate brake fluid in both directions between the first master cylinder 32 and the first flow path 45a of the main flow path 45. When a specified control current is applied to the solenoid and the first master cut valve 64 is closed, the flow of brake fluid in the first master flow path 61 is cut off.

The second master flow path 62 has a second master cut valve 65 in the middle. The second master cut valve 65 is provided on the brake fluid supply path from the second master cylinder 33 to each wheel cylinder 23. The second master cut valve 65 also has a solenoid and a spring that are ON / OFF controlled, and the valve closed state is guaranteed by the electromagnetic force generated by the solenoid when the specified control current is supplied, and the solenoid is not energized. It is a normally open type electromagnetic control valve that is opened when it is in a state. The second master cut valve 65 in the open state can circulate brake fluid in both directions between the second master cylinder 33 and the second flow path 45b of the main flow path 45. When the solenoid is energized and the second master cut valve 65 is closed, the flow of brake fluid in the second master flow path 62 is cut off.

Further, the stroke simulator 69 is connected to the second master flow path 62 via the simulator cut valve 68 on the upstream side of the second master cut valve 65. That is, the simulator cut valve 68 is provided in the flow path connecting the second master cylinder 33 and the stroke simulator 69. The simulator cut valve 68 has a solenoid and a spring that are ON / OFF controlled, and the valve open state is guaranteed by the electromagnetic force generated by the solenoid when the specified control current is supplied, and the solenoid is in the non-energized state. It is a normally closed electromagnetic control valve that is closed in some cases. When the simulator cut valve 68 is in the closed state, the flow of brake fluid between the second master flow path 62 and the stroke simulator 69 is cut off. When the solenoid is energized and the simulator cut valve 68 is opened, the brake fluid can be circulated in both directions between the second master cylinder 33 and the stroke simulator 69.

The stroke simulator 69 includes a plurality of pistons and springs, and creates a reaction force corresponding to the pedaling force of the brake pedal 24 by the driver when the simulator cut valve 68 is opened. It is preferable that the stroke simulator 69 having a multi-stage spring characteristic is adopted in order to improve the feeling of the brake operation by the driver.

The hydraulic actuator 40 is formed with an accumulator flow path 63 in addition to the first master flow path 61 and the second master flow path 62. One end of the accumulator flow path 63 is connected at a position between the separation valve 60 and the orifice 100 of the main flow path 45, and the other end is connected to the accumulator pipe 39 communicating with the accumulator 35.

The accumulator flow path 63 has a pressure boosting linear control valve 66 that functions as a hydraulic pressure control valve in the middle. Further, the accumulator flow path 63 and the second flow path 45b of the main flow path 45 are connected to the reservoir flow path 55 via a pressure reducing linear control valve 67 that functions as a hydraulic pressure control valve. The booster linear control valve 66 and the pressure reducing linear control valve 67 each have a linear solenoid and a spring, and both are normally closed electromagnetic control valves that are closed when the solenoid is in a non-energized state. The valve opening degree of the pressure boosting linear control valve 66 and the pressure reducing linear control valve 67 is adjusted in proportion to the current supplied to each solenoid.

The pressure boosting linear control valve 66 is provided as a pressure boosting control valve common to each wheel cylinder 23 provided in plurality corresponding to each wheel. Similarly, the pressure reducing linear control valve 67 is also provided as a common pressure reducing control valve for each wheel cylinder 23. That is, in the present embodiment, the pressure boosting linear control valve 66 and the pressure reducing linear control valve 67 are a pair of common control valves that control the supply and discharge of the brake fluid sent from the power hydraulic pressure source 30 to each wheel cylinder 23. It is provided as. If the pressure boosting linear control valve 66 and the pressure reducing linear control valve 67 are shared for each wheel cylinder 23 in this way, it is preferable from the viewpoint of cost as compared with providing a linear control valve for each wheel cylinder 23.

Here, the differential pressure between the inlet and outlet of the pressure boosting linear control valve 66 corresponds to the differential pressure between the brake fluid pressure in the accumulator 35 and the brake fluid pressure in the main flow path 45, and corresponds to the differential pressure between the inlet and outlet of the pressure reducing linear control valve 67. The differential pressure between them corresponds to the differential pressure between the brake fluid pressure in the main flow path 45 and the brake fluid pressure in the reservoir 34. Further, the electromagnetic driving force corresponding to the power supplied to the linear solenoids of the pressure boosting linear control valve 66 and the pressure reducing linear control valve 67 is set to F1, the spring urging force is set to F2, and the pressure increasing linear control valve 66 and the pressure reducing linear control valve Assuming that the differential pressure acting force according to the differential pressure between the entrances and exits of 67 is F3, the relationship of F1 + F3 = F2 is established. Therefore, by continuously controlling the power supplied to the linear solenoids of the pressure boosting linear control valve 66 and the pressure reducing linear control valve 67, the differential pressure between the inlet and outlet of the pressure boosting linear control valve 66 and the pressure reducing linear control valve 67 is controlled. can do.

In the hydraulic brake unit 20, the power hydraulic source 30 and the hydraulic actuator 40 are controlled by the brake ECU 70. The brake ECU 70 is configured as a microprocessor including a CPU, and includes a ROM for storing various programs, a RAM for temporarily storing data, an input / output port, a communication port, and the like in addition to the CPU. The brake ECU 70 can communicate with the higher-level hybrid ECU 7 and the like, and constitutes the pump 36 of the power hydraulic pressure source 30 and the hydraulic actuator 40 based on the control signals from the hybrid ECU 7 and the signals from various sensors. The electromagnetic control valves 51 to 54, 56 to 59, 60, 64 to 68 are controlled.

Further, the master pressure sensor 71, the accumulator pressure sensor 72, and the control pressure sensor 73 are connected to the brake ECU 70. The master pressure sensor 71 detects the pressure of the brake fluid in the second master flow path 62 on the upstream side of the second master cut valve 65, that is, the pressure of the second master cylinder, and gives a signal indicating the detected value to the brake ECU 70. .. The accumulator pressure sensor 72 detects the pressure of the brake fluid in the accumulator flow path 63 on the upstream side of the pressure boosting linear control valve 66, that is, the accumulator pressure, and gives a signal indicating the detected value to the brake ECU 70. The control pressure sensor 73 detects the pressure of the brake fluid in the first flow path 45a of the main flow path 45, and gives a signal indicating the detected value to the brake ECU 70. The detected values of the pressure sensors 71 to 73 are sequentially given to the brake ECU 70 at predetermined time intervals, and are stored and held in a predetermined storage area of the brake ECU 70.

When the separation valve 60 is opened and the first flow path 45a and the second flow path 45b of the main flow path 45 communicate with each other, the output value of the control pressure sensor 73 is the low pressure of the pressure boosting linear control valve 66. Since the hydraulic pressure on the side is shown and the hydraulic pressure on the high pressure side of the pressure reducing linear control valve 67 is shown, this output value can be used for controlling the pressure increasing linear control valve 66 and the pressure reducing linear control valve 67. When the pressure boosting linear control valve 66 and the pressure reducing linear control valve 67 are closed and the first master cut valve 64 is in the open state, the output value of the control pressure sensor 73 is the first master cylinder pressure. Is shown. Further, the separation valve 60 is opened so that the first flow path 45a and the second flow path 45b of the main flow path 45 communicate with each other, and the ABS holding valves 51 to 54 are opened, while each ABS pressure reducing valve 56 is opened. When ~ 59 is closed, the output value of 73 of the control pressure sensor indicates the working fluid pressure acting on each wheel cylinder 23, that is, the wheel cylinder pressure.

Further, the sensor connected to the brake ECU 70 also includes the stroke sensor 25 provided on the brake pedal 24. The stroke sensor 25 detects the pedal stroke as the operation amount of the brake pedal 24, and gives a signal indicating the detected value to the brake ECU 70. The output value of the stroke sensor 25 is also sequentially given to the brake ECU 70 at predetermined time intervals, and is stored and held in a predetermined storage area of the brake ECU 70. A brake operation state detecting means other than the stroke sensor 25 may be provided in addition to the stroke sensor 25 or in place of the stroke sensor 25 and connected to the brake ECU 70. Examples of the brake operation state detecting means include a pedal pedal force sensor that detects the operating force of the brake pedal 24, a brake switch that detects that the brake pedal 24 is depressed, and the like.

The brake control device according to the present embodiment including the hydraulic brake unit 20 configured as described above can execute the brake regenerative cooperative control. Upon receiving the braking request, the brake ECU 70 starts processing. The braking request is generated when a braking force should be applied to the vehicle, for example, when the driver operates the brake pedal 24. The brake ECU 70 repeatedly executes control at a predetermined control cycle until, for example, the operation of the brake pedal 24 is released.

In response to the braking request, the brake ECU 70 calculates the target deceleration, that is, the required braking force. The brake ECU 70 calculates a target deceleration based on, for example, master cylinder pressure and stroke measurements. Here, the brake ECU 70 distributes the target deceleration to each wheel according to the desired braking force distribution and calculates the target braking force of each wheel, and in the subsequent processing, the regenerative braking force and the hydraulic braking force are calculated based on the target braking force. May be controlled.

The brake ECU 70 calculates the required regenerative braking force based on the target deceleration. For example, the brake ECU 70 sets the target deceleration as the required regenerative braking force when the target deceleration is smaller than the maximum regenerative braking force that can be generated, and the maximum regenerative braking force when the target deceleration is equal to or greater than the maximum regenerative braking force. Is the required regenerative braking force. Further, the brake ECU 70 may calculate the required regenerative braking force by correcting the target deceleration instead of using the target deceleration as it is as the required regenerative braking force. The required regenerative braking force may be corrected higher or lower than the target deceleration. The brake ECU 70 transmits the calculated required regenerative braking force to the hybrid ECU 7. The brake ECU 70 and the hybrid ECU 7 are connected to the in-vehicle network. The brake ECU 70 transmits the required regenerative braking force to its in-vehicle network.

The hybrid ECU 7 receives the required regenerative braking force from the in-vehicle network. The hybrid ECU 7 controls the regenerative braking unit 10 with the received required regenerative braking force as the regenerative braking force target value. As a result, the hybrid ECU 7 transmits the effective value of the regenerative braking force actually generated to the brake ECU 70 through the in-vehicle network.

The brake ECU 70 receives the effective regenerative braking force value from the hybrid ECU 7. The brake ECU 70 calculates the required hydraulic braking force, which is the braking force to be generated by the hydraulic brake unit 20, by subtracting the regenerative braking force effective value from the target deceleration. The brake ECU 70 calculates the target hydraulic pressure of each wheel cylinder 23FR to 23RL based on the required hydraulic pressure braking force. The brake ECU 70 may correct the required hydraulic braking force or the target hydraulic pressure. The brake ECU 70 controls the hydraulic actuator 40 so that the wheel cylinder pressure becomes the target hydraulic pressure. For example, the brake ECU 70 determines the value of the control current supplied to the booster linear control valve 66 and the pressure reducing linear control valve 67 by feedback control.

As a result, in the hydraulic brake unit 20, brake fluid is supplied from the power hydraulic pressure source 30 to each wheel cylinder 23 via the pressure boosting linear control valve 66, and braking force is applied to the wheels. Further, the brake fluid is discharged from each wheel cylinder 23 via the pressure reducing linear control valve 67 as needed, and the braking force applied to the wheels is adjusted. In the present embodiment, the wheel cylinder pressure control system includes a power hydraulic pressure source 30, a pressure boosting linear control valve 66, a pressure reducing linear control valve 67, and the like. The so-called brake-by-wire type braking force control is performed by the wheel cylinder pressure control system. The wheel cylinder pressure control system is provided in parallel with the brake fluid supply path from the master cylinder unit 27 to the wheel cylinder 23.

When performing brake-by-wire type braking force control, the brake ECU 70 closes the first master cut valve 64 so that the brake fluid sent from the first master cylinder 32 is not supplied to the wheel cylinder 23. Further, the brake ECU 70 closes the second master cut valve 65 and opens the simulator cut valve 68. This is so that the brake fluid sent from the second master cylinder 33 when the driver operates the brake pedal 24 is supplied to the stroke simulator 69 instead of the wheel cylinder 23. During the brake regeneration coordinated control, a differential pressure corresponding to the magnitude of the regenerative braking force acts between the upstream and downstream of the first master cut valve 64 and the second master cut valve 65.

In the above-mentioned brake regenerative cooperative control, the regenerative braking force is preferentially generated, and the shortage of the regenerative braking force with respect to the required braking force is compensated by the friction braking force. The present embodiment is not limited to such a regeneration priority mode. For example, the control unit may control the braking force by the regenerative assist mode in which the regenerative braking force is assisted, or distributes the target deceleration to the preset regeneration target value and friction target value distribution. The braking force may be controlled in the regenerative combined mode in which the regenerative braking force and the friction braking force are generated.

As described above, in the present embodiment, the first master flow path 61 connected to the first master cylinder 32 and the second master flow path 62 connected to the second master cylinder 33 are formed. The first master flow path 61 can communicate with the wheel cylinder 23RL for the left rear wheel and the wheel cylinder 23FR for the right front wheel, and the second master flow path 62 can communicate with the wheel cylinder 23FL for the left front wheel and the right rear wheel. It forms a so-called "X pipe" that can communicate with the wheel cylinder 23RR.

By adopting such "X piping", for example, when a fail such as liquid leakage occurs in the flow path system including the first master flow path 61 or the flow path system including the second master flow path 62, It is possible to realize a fail-safe function that generates sufficient braking force with only one flow path system. For example, when a liquid leak occurs in the flow path system including the second master flow path 62 and a braking request is made by operating the brake pedal 24 of the driver, the pressure boosting linear control valve 66 and the second master cut valve 65 Is closed and the first master cut valve 64 is opened. In that case, the brake fluid flowing out from the first master cylinder 32 is supplied to the wheel cylinder 23RL for the left rear wheel and the wheel cylinder 23FR for the right front wheel. That is, braking force can be generated between one front wheel and one rear wheel at diagonal positions. Similarly, even if a liquid leak occurs in the flow path system including the first master flow path 61, the pressure boosting linear control valve 66 and the first master cut valve 64 are closed and the second master cut valve 65 is opened. To speak. As a result, the brake fluid flowing out from the second master cylinder 33 is supplied to the wheel cylinder 23FL for the left front wheel and the wheel cylinder 23RR for the right rear wheel. That is, braking force can be generated between one front wheel and one rear wheel at diagonal positions. In this case, the front wheel disc brake unit 21 can be used regardless of which of the first master flow path 61 and the second master flow path 62 is used. That is, if the braking capacity of the disc brake unit 21 on the front wheel side is set to be larger than the braking capacity of the disc brake unit 21 on the rear wheel side due to the weight distribution of the vehicle, etc., any flow path system can be used. The disc brake unit 21 on the front wheel side, which has a large braking ability, is used, and a sufficient braking ability can be exhibited. In other words, if the conditions such as the weight distribution of the vehicle are satisfied, the disc brake unit 21 on the rear wheel side can be used with a smaller braking capacity than the disc brake unit 21 on the front wheel side. As a result, it is possible to contribute to cost reduction and miniaturization of the disc brake unit 21. In addition, as a brake device for the rear wheels, an inexpensive disc brake

In this embodiment, the master cylinder portion of the master cylinder unit 27 is separated into two chambers, the first master cylinder 32 and the second master cylinder 33, and the brake fluid in substantially the same hydraulic pressure state is substantially at the same timing. Can be supplied to the first master flow path 61 and the second master flow path 62. Therefore, the braking force when braking only in the flow path system including the first master flow path 61 and when braking only in the flow path system including the second master flow path 62 becomes substantially the same, and the brake feeling. It is possible to suppress giving the driver a sense of discomfort.

By the way, when the above-mentioned "X pipe" is adopted, there are some items to be considered when executing the brake-by-wire type braking force control for supplying the brake fluid from the power hydraulic pressure source 30. That is, in order to realize "X piping", a separation valve 60 is provided in the main flow path 45 and is divided into a first flow path 45a and a second flow path 45b. Then, when the brake fluid is supplied from the power hydraulic pressure source 30, the separation valve 60 is opened to communicate the first flow path 45a and the second flow path 45b, but the first flow path 45a connects the separation valve 60. The flow path system passes through, and the second flow path 45b becomes a flow path system that does not pass through the separation valve 60. Since the separation valve 60 causes flow resistance even when the valve is open, it causes a control time difference and a pressure difference by passing through the separation valve 60. In the "X pipe", if a control time difference or a pressure difference occurs between the first flow path 45a and the second flow path 45b, the braking balance of the vehicle may be lost and the brake feeling may be deteriorated.

Therefore, in this embodiment, Burekifu via the pressure-increasing linear control valve 66 is a hydraulic control valve when the Rude is supplied from the first passage 45a and second passage 45b to the wheel cylinders 23, the first There is no control time difference or pressure difference between the flow path 45a side and the second flow path 45b side. Specifically, the brake fluid is supplied so as to reduce the state difference between the first flow path 45a in which the brake fluid flows in through the separation valve 60 and the brake fluid supply state in the second flow path 45b that does not pass through. An orifice 100 that functions as an adjusting unit for adjusting the state is provided. The brake fluid supply state adjusted by the orifice 100, which is an adjusting unit, represents, for example, the state when the brake fluid is supplied, such as the flow rate and pressure when the brake fluid is supplied, and the timing of the brake fluid supply. Can be. The flow resistance of the orifice 100 is substantially the same as the flow resistance when the separation valve 60 is opened. This adjustment can be easily achieved by adjusting the cross-sectional area of the orifice 100. When the adjusting portion is composed of the orifice 100, the orifice 100 does not need to confirm the open / closed state unlike the separation valve 60, so that it is not necessary to provide a pressure sensor for confirming it, and the flow path configuration is simplified. There is a merit that it can be converted. In this case, the pressure in the first flow path 45a and the second flow path 45b can be managed by the control pressure sensor 73.

In this way, by arranging the orifice 100 that generates the same flow resistance as the flow resistance of the separation valve 60 across the connection position of the accumulator flow path 63 in the main flow path 45, the first flow from the boosting linear control valve 66 It is possible to suppress the occurrence of a control time difference or a pressure difference when the brake fluid is supplied to the road 45a and the second flow path 45b. As a result, even when the "X pipe" is adopted, it is possible to suppress a decrease in the brake feeling during normal braking using the power hydraulic pressure source 30. Even when the separation valve 60 is closed and only the second flow path 45b is used, the presence of the orifice 100 does not affect the individual flow paths 43 and 44, so that a braking force is generated using the second master flow path 62. Can be done well.

By the way, in the case of the configuration of the hydraulic brake unit as shown in FIG. 2, when performing ABS control, the brake fluid is supplied to the wheel cylinder 23 from the pressure boosting linear control valve 66. Since the hydraulic pressure is held and depressurized during ABS control by closing the ABS holding valves 51 to 54, the volume upstream of the ABS holding valves is only the volume up to the boosting linear control valve 66, which is extremely small. That is, the flowable volume of the brake fluid that can be formed between the pressure boosting linear control valve 66 and each wheel cylinder 23 becomes very small. When the hydraulic pressure is controlled by the booster linear control valve 66 in such a state where the flowable volume is very small, the control sensitivity becomes very high. As a result, hydraulic hunting and frequent operation (control hunting) of the pressure boosting linear control valve 66 occur, leading to an increase in operating noise and vibration, and a decrease in brake feeling due to a difference in hydraulic response and a difference in hydraulic pressure. It may cause it. In addition, the booster linear control valve 66 operates frequently, which may shorten the life of the booster linear control valve 66.

Therefore, in the present embodiment, the operation of the booster linear control valve 66 is synchronized with the opening / closing operation of the ABS holding valves 51 to 54. For example, when performing ABS control, the fadeback control of the booster linear control valve 66 is controlled according to the number of ABS holding valves that are closed, that is, the number of ABS holding valves that are not communicating with the wheel cylinder 23. Change the gain.

FIG. 3 is an explanatory diagram illustrating the relationship between the number of ABS control valves that are closed and the control gain of the booster linear control valve 66. As shown in Fig. 3, there are 16 combinations of open / closed states of the ABS control valve. Then, when classified by the "control mode" in which the volume between the pressure boosting linear control valve 66 and the ABS control valve can be regarded as the same, there are nine types. In FIG. 3, ABS control mode 1 has the smallest flowable volume of brake fluid, and ABS control mode 9 has a larger flowable volume. Therefore, the gain of the booster linear control valve 66 is set for the ABS control modes 1 to 9. That is, the control gain 1 is set so that the control is the most insensitive and the control becomes more sensitive toward the control gain 9. In the present embodiment, since the disc brake unit 21 on the front wheel side has a braking ability larger than that of the disc brake unit 21 on the rear wheel side, the volume of the wheel cylinder 23 on the front wheel side is the wheel on the rear wheel side. Larger than cylinder 23. Therefore, the ABS control mode is defined on the assumption that the larger the number of open ABS holding valves on the front wheel side, the larger the volume.

For example, when all the ABS holding valves are opened and the volume from the pressure boosting linear control valve 66 to the wheel cylinder 23, that is, the flowable volume of the brake fluid is large as in ABS control mode 9, the ABS control mode The flow of brake fluid is slower than when the flowable volume from the pressure boosting linear control valve 66 to the wheel cylinder 23 is small as in 2. Therefore, a high control gain is applied so as to react sensitively to the change in hydraulic pressure detected by the control pressure sensor 73 so that the target hydraulic pressure value can be reached smoothly. In this case, even if the control gain of the pressure boosting linear control valve 66 is increased to increase the hydraulic pressure fluctuation, the fluctuation can be absorbed by a large flowable volume, so that hydraulic hunting and control hunting can be suppressed.

On the other hand, when the flowable volume from the pressure boosting linear control valve 66 to the wheel cylinder 23 is small as in ABS control mode 2, the flow of brake fluid becomes more sensitive than in ABS control mode 9. Therefore, a small control gain is applied so as to be insensitive to the hydraulic pressure change detected by the control pressure sensor 73. In this case, excessive hydraulic pressure fluctuation can be suppressed by reducing the control gain of the pressure boosting linear control valve 66, so that hydraulic hunting and control hunting can be suppressed. FIG. 4 shows that the control gain of the booster linear control valve 66 is changed in response to a change in the ABS control mode.

In another embodiment, a small dedicated control gain may be applied when any of the ABS holding valves is closed, regardless of the number of times the ABS holding valves are opened and closed. For the control gain, the correspondence between the number of ABS holding valves whose open / closed state has been switched and the change in flow pressure that occurs at that time is acquired in advance by testing, etc., and vibrations and abnormal noise caused by fluctuations in flow pressure are obtained. It is preferable to determine the optimum value so that the occurrence can be suppressed.

When the control gain of the booster linear control valve 66 is changed in response to a change in the ABS control mode, the control gain after the change is enabled immediately after the control gain is changed to control the booster linear control valve 66. You may start. In this case, the change in the control gain can be sensitively reflected in the booster linear control valve 66. Further, in another embodiment, after the control gain is changed, the control state of the booster linear control valve 66 is not changed for a predetermined time, and the changed control gain is enabled after the predetermined time elapses. May be good. As described above, when the flowable volume of the brake fluid is small, the hydraulic pressure fluctuation of the brake fluid in the flow path due to the opening / closing operation of the ABS holding valve becomes large, and unnecessary vertical fluctuation of the hydraulic pressure occurs during the transition period. Occurs. If the booster linear control valve 66 executes control following this temporary change in hydraulic pressure, the control becomes excessive and causes vibration or abnormal noise. In addition, it may cause further fluctuations in hydraulic pressure or delay the convergence of fluctuations. Therefore, after changing the control gain according to the open / closed state of the ABS holding valve, the control state of the booster linear control valve 66 is not changed for a predetermined time, and the booster linear control valve corresponding to the hydraulic pressure fluctuation in the transition period. The feedback control to 66 is temporarily stopped. For example, in FIG. 4, in the portions A1 to A4 where the control gain is changed, the activation of the changed control gain is delayed by, for example, several msec. Then, after the fluctuation of the hydraulic fluid pressure in the flow path due to the opening / closing operation of the ABS holding valve becomes stable, the pressure boosting linear control valve 66 is controlled by enabling the changed control gain. As a result, it is possible to follow the fluctuation of the hydraulic pressure accompanying the opening / closing operation of the ABS holding valve by controlling the pressure boosting linear control valve 66 less frequently. That is, it is possible to improve the suppression efficiency of hydraulic hunting and control hunting. In order not to change the control state of the booster linear control valve 66 for a predetermined time, the change of the control gain itself may be delayed for a predetermined time. In this way, when the control state based on the control gain is delayed so as not to be changed for a predetermined time so as not to be delayed. There is also an advantage that it can be handled with a smaller number of control gain types than. After a predetermined time has elapsed from the opening / closing operation of the ABS holding valve without changing the control gain, the hydraulic pressure fluctuation of the brake fluid in the flow path due to the opening / closing operation of the ABS holding valve becomes stable, and then the pressure boosting linear control valve 66 Control may be performed. In this case as well, excessive control of the pressure boosting linear control valve 66 can be suppressed, and the effect of suppressing hydraulic pressure hunting and control hunting can be obtained.

By the way, in the hydraulic brake unit including the orifice 100 as shown in FIG. 2, the accumulator pressure drops when an open failure occurs in which the booster linear control valve 66 is fixed in the valve open state. That is, when the booster linear control valve 66 opens and fails, the brake fluid supplied from the accumulator 35 is provided between the separation valve 60 and the orifice 100 via the accumulator flow path 63. At this time, even if the separation valve 60 is closed, it will flow to the orifice 100 side. Then, since the second master cut valve 65 is normally opened, the brake fluid supplied from the accumulator 35 returns to the reservoir 34 via the second master cylinder 33, and as a result, the accumulator pressure of the accumulator 35 increases. It will drop.

In this way, when the accumulator pressure drops, braking force control using the power hydraulic pressure source 30 as the hydraulic pressure source cannot be expected, so the brake ECU 70 shifts to backup control using the master cylinder unit 27 as the hydraulic pressure source. Become. At this time, since the booster linear control valve 66 has opened and failed, the brake fluid sent from the second master cylinder 33 flows back through the booster linear control valve 66 and returns to the reservoir 34, so that the left front wheel wheel. No braking force is generated on the cylinder 23FL and the wheel cylinder 23RR on the right rear wheel. That is, braking is performed only by the wheel cylinder 23RL of the left rear wheel and the wheel cylinder 23FR of the right front wheel operated by the brake fluid sent from the first master cylinder 32. Further, in this case, since the accumulator pressure is not supplied and the pedaling force assist by the hydraulic pressure booster 31a cannot be obtained, the hydraulic pressure generated only by the pedaling force of the driver is introduced into the wheel cylinder 23. Will lead to an increase in labor.

Generally, in a power hydraulic pressure source provided with an accumulator, when the accumulator pressure drops, the pump continuously operates to increase the accumulator pressure to a predetermined target pressure. This control mode is usually called a pump control mode. If the motor drive time is continuously driven beyond a preset predetermined time during this normal pump control mode execution, the pump is intermittently driven to prevent malfunction or seizure of the motor due to excessive heat generation of the pump. It is set. Such a control mode is called an intermittent pump control mode. Control logic for protection purposes such as this intermittent pump control mode is important, but in this embodiment, priority is given to improving the brake feeling, and when the pump is stopped when the accumulator pressure drops, the brake is applied. When the operation of the pedal 24 is detected, the pump is operated exceptionally.

That is, in the intermittent pump control mode, when the pump is stopped when the accumulator pressure drops, the brake ECU 70 operates the pump 36 by driving the motor 36a when the stroke sensor 25 detects the depression of the brake pedal 24. In this case, the encapsulation pressure of the accumulator 35 upstream of the booster linear control valve 66 rises instantaneously. By recovering the accumulator pressure, the accumulator pressure can be supplied to the hydraulic booster 31a, the pedaling force of the brake pedal 24 can be assisted, and the operation burden on the driver can be reduced. Further, the accumulator pressure accumulated in the accumulator 35 can be supplied to the wheel cylinder 23FL of the left front wheel and the wheel cylinder 23RR of the right rear wheel via the pressure boosting linear control valve 66 which is open. That is, since the output ports of the first master cylinder 32 and the second master cylinder 33 are closed by the operation of the brake pedal 24, the brake fluid supplied to the left front wheel wheel cylinder 23FL and the right rear wheel wheel cylinder 23RR is stored. Does not return to 34. Therefore, the wheel cylinder 23FL on the left front wheel and the wheel cylinder 23RR on the right rear wheel can generate braking force by the accumulator pressure.

FIG. 5 is a flowchart illustrating a control state of the pump 36. It should be noted that the brake ECU 70 is described as being in the normal pump control mode in the initial state in which the ignition switch of the vehicle is turned on. First, the brake ECU 70 confirms whether the control state of the pump 36 is during normal pump control (S100). In S100, when the control state of the pump 36 is during normal pump control execution (Y in S100), that is, when the accumulator pressure falls below a predetermined target pressure, the motor 36a drives the pump 36 to target the accumulator pressure. Boost to pressure. At this time, the brake ECU 70 confirms whether the continuous drive time of the pump 36 is Xsec or less (S102). Xsec is a value that can be determined in advance by the capacity of the motor 36a and the pump 36 by a test or the like, and a value that does not cause seizure or heat generation due to continuous driving is set. In S102, when the continuous drive time of the pump 36 is Xsec or less (Y in S102), the normal pump control can be continued, and the process shifts to S100 and the flow process is repeated. On the other hand, the brake ECU70 is used when the continuous drive time of the pump 36 exceeds Xsec (N in S102) when the accumulator pressure does not reach the target pressure, or when the normal pump control is not being executed in S100 (N in S100). , Perform intermittent pump control mode processing (S104). After that, it returns to S100 and repeats this flow. In the intermittent pump control mode processing, for example, when the pressure boosting linear control valve 66 malfunctions or a liquid leak occurs in the flow path system as described above, the accumulator pressure is greatly reduced due to frequent braking requests even if the system is normal. It is executed when it takes longer than usual to accumulate pressure, such as in the case of.

FIG. 6 is a flowchart illustrating the details of the intermittent pump control mode processing in FIG. The brake ECU 70 monitors whether or not the braking determination is made based on the signal from the stroke sensor 25 during the execution of the intermittent pump control mode processing (S106). If the braking determination is not in the ON state (N in S106), or if the intermittent pump control is not being executed (N in S108), the intermittent pump control is executed (S110). That is, when the continuous drive time of the pump 36 reaches Xsec, the control of stopping the drive of the pump 36 for a predetermined time, for example, Ysec is executed. After that, the pump 36 is driven again with Xsec as the upper limit, and when Xsec elapses, the control of repeating the stop with Ysec as the upper limit is executed. If intermittent pump control has already been executed in S108 (Y in S108), the processing in S110 is skipped. When the accumulator pressure reaches the target pressure during intermittent pump control (Y in S112), the brake ECU 70 returns the control mode to the normal pump control mode (S114) and ends this flow. Further, in S112, when the accumulator pressure does not reach the target pressure (N in S112), the processing in S114 is skipped and the processing in the intermittent pump control mode is continued.

In S106, when the braking determination is ON (Y in S106), the brake ECU 70 exceptionally drives the pump 36 at that timing to boost the accumulator pressure even during intermittent pump control (S116). When the braking determination shifts to the OFF state (Y of S118), the brake ECU 70 stops driving the pump 36 which was exceptionally operated (S120), ends this flow, and continues the intermittent pump control. Further, in S118, when the braking determination remains ON (N in S118), the brake ECU 70 skips the processing of S120, continues the exceptional continuous drive of the pump 36, and ends this flow.

As described above, in the brake control device including the intermittent pump control of the pump 36 and having the orifice 100 as the adjusting unit, even if a failure occurs in the booster linear control valve 66, it is good to provide an exception mode for the intermittent pump control. A good brake feeling can be obtained.

FIG. 7 is a system diagram showing a hydraulic brake unit of another embodiment. In the hydraulic brake unit 200 shown in FIG. 7, the regulator pipe 74 extending from the regulator 31 is connected to the hydraulic actuator 40, and the regulator flow path 76 having the regulator cut valve 75 in the middle is a separation valve of the second flow path 45b. It is connected between 60 and the orifice 100. Except for this point, the configurations of the hydraulic brake unit 20 and the hydraulic brake unit 200 shown in FIG. 2 are substantially the same. Therefore, members having similar functions are designated by the same reference numerals and the description thereof will be omitted.

As described with reference to FIGS. 3 and 4, when ABS control is performed by the hydraulic brake unit 20, brake fluid is supplied to the wheel cylinder 23 from the pressure boosting linear control valve 66. At this time, the hydraulic pressure is held and depressurized during ABS control by closing the ABS holding valves 51 to 54, so that the upstream volume is only the volume up to the boosting linear control valve 66, and the brake fluid flows. The possible volume becomes very small. As a result, control hunting occurs during ABS control, which causes an increase in operating noise and vibration. It also caused a decrease in brake feeling. Therefore, during ABS control, the hydraulic brake unit 200 closes the booster linear control valve 66 and switches from the supply of brake fluid via the booster linear control valve 66 to the supply of brake fluid via the regulator 31. Therefore, the regulator pressure adjusted directly from the regulator 31 is supplied.

The regulator cut valve 75 has a solenoid and a spring that are ON / OFF controlled, and the valve open state is guaranteed by the electromagnetic force generated by the solenoid when the specified control current is supplied, and the solenoid is in the non-energized state. It is a normally closed electromagnetic control valve that is closed in some cases. The closed regulator cut valve 75 cuts off the flow of brake fluid between the regulator 31 and the second flow path 45b of the main flow path 45. When the solenoid is energized and the regulator cut valve 75 is opened, the brake fluid can be circulated in both directions between the regulator 31 and the second flow path 45b of the main flow path 45. The regulator 31 reduces the accumulator pressure of the accumulator 35 to a hydraulic pressure corresponding to the pedaling force of the brake pedal 24. Therefore, a stable regulator pressure can be provided to each wheel cylinder 23, and the brake fluid is either shut off or passed by the regulator cut valve 75, which is considered by the hydraulic brake unit 20 during ABS control. There is no required control hunting. Therefore, it is possible to easily suppress the generation of operating noise and vibration during ABS control.

Further, in the case of the hydraulic brake unit 200, since the pressure boosting linear control valve 66 is closed and not operated during ABS control, the pressure boosting linear control valve 66 having lower durability than the hydraulic brake unit 20 is used. Can contribute to cost reduction. Further, since the pressure boosting linear control valve 66 is not used during ABS control, the number of controls can be reduced, which can contribute to the reduction of control noise and vibration, and can also contribute to the extension of life. Further, even when the brake fluid is supplied from the regulator 31 during ABS control, the main flow path 45 has an orifice 100 that generates a flow resistance equivalent to that of the separation valve 60, so that the first flow path 45a and the second flow path 45a and the second flow path There is no difference in hydraulic response or hydraulic pressure between 45b and 45b. As a result, a decrease in brake feeling can be suppressed.

When executing braking control by a normal brake-by-wire method other than ABS control, the regulator cut valve 75 is closed and the flow path passes through the pressure boosting linear control valve 66 as in the hydraulic brake unit 20. Control is executed.

FIG. 8 is a system diagram showing a hydraulic brake unit of another embodiment. In the hydraulic brake unit 202 shown in FIG. 8, the regulator pipe 74 extending from the regulator 31 is connected to the hydraulic actuator 40, and the regulator flow path 76 having the pressure boosting linear control valve 66 in the middle is the second flow path 45b. It is connected between the separation valve 60 and the orifice 100. Further, in the path of the accumulator flow path 63 connected between the separation valve 60 of the second flow path 45b and the orifice 100, an accumulator cut valve 78 that shuts off the accumulator flow path 63 in the middle is provided. Further, the pressure reducing linear control valve 67 provided in the regulator flow path 76 connected to the second flow path 45b is connected to the reservoir flow path 55. Except for this point, the configurations of the hydraulic brake unit 20 and the hydraulic brake unit 202 shown in FIG. 2 are substantially the same. Therefore, members having the same function are designated by the same reference numerals, and the description thereof will be omitted.

The pressure boosting linear control valve 66 and the pressure reducing linear control valve 67 in the hydraulic brake unit 202 have a linear solenoid and a spring, respectively, like those of the hydraulic brake unit 20, when the solenoids are not energized. It is a normally closed solenoid control valve that is closed to the ground. The valve opening degree of the pressure boosting linear control valve 66 and the pressure reducing linear control valve 67 is adjusted in proportion to the current supplied to each solenoid. The regulator pressure sensor 79 detects the pressure of the brake fluid in the regulator flow path 76 on the upstream side of the pressure boosting linear control valve 66, that is, the regulator pressure, and gives a signal indicating the detected value to the brake ECU 70.

The pressure boosting linear control valve 66 is provided as a pressure boosting control valve common to each wheel cylinder 23 provided in plurality corresponding to each wheel. Similarly, the pressure reducing linear control valve 67 is also provided as a common pressure reducing control valve for each wheel cylinder 23. That is, in the hydraulic brake unit 202, the pressure boosting linear control valve 66 and the pressure reducing linear control valve 67 serve as a pair of common control valves that control the supply and discharge of the brake fluid sent from the regulator 31 to each wheel cylinder 23. It is provided. If the pressure boosting linear control valve 66 and the pressure reducing linear control valve 67 are shared for each wheel cylinder 23 in this way, it is preferable from the viewpoint of cost as compared with providing a linear control valve for each wheel cylinder 23.

The accumulator cut valve 78 has a solenoid and a spring that are ON / OFF controlled, and the valve open state is guaranteed by the electromagnetic force generated by the solenoid when the specified control current is supplied, and the solenoid is in the non-energized state. It is a normally closed electromagnetic control valve that is closed in some cases. The closed accumulator cut valve 78 blocks the flow of brake fluid between the accumulator 35 and the second flow path 45b of the main flow path 45. When the solenoid is energized and the accumulator cut valve 78 is opened, the brake fluid can be circulated in both directions between the accumulator 35 and the second flow path 45b of the main flow path 45.

In the hydraulic brake unit 202, special controls such as braking force control during traction control that is controlled when the brake pedal 24 is not operated and braking force control during vehicle stability control system operation that prevents skidding are accumulator cuts. It is controlled by the accumulator pressure supplied from the accumulator 35 via the valve 78. On the other hand, the braking control for operating the other brake pedals 24 is controlled by the regulator pressure supplied via the pressure increasing linear control valve 66 and the depressurizing linear control valve 67. That is, when the braking force is controlled by the linear control of the pressure increasing linear control valve 66 and the depressurizing linear control valve 67, the supply of brake fluid from the accumulator 35 is cut off by the accumulator cut valve 78.

In this case, the pressure increasing linear control valve 66 and the depressurizing linear control valve 67 are supplied with a regulator pressure adjusted for decompression by the regulator 31 based on the operation of the driver's brake pedal 24. Therefore, a control valve having a smaller durability than that to which a high-pressure accumulator pressure is supplied, such as the pressure-increasing linear control valve 66 and the pressure-reducing linear control valve 67 in the hydraulic brake unit 20, can be used. Further, since the control pressure is much lower than the accumulator pressure, the controllability of the pressure increasing linear control valve 66 and the depressurizing linear control valve 67 can be improved, and the load is reduced, which can contribute to the extension of the life. Further, since the regulator pressure adjusted according to the operation amount of the brake pedal 24 is lower than the accumulator pressure, there is an advantage that the operating noise and vibration of the booster linear control valve 66 can be reduced.

In the configuration of the hydraulic brake unit 202, when ABS control is performed, the regulator pressure can be provided according to the operation amount of the brake pedal 24, so that the pressure boosting linear control valve 66 can be fully opened. As a result, the control of the pressure boosting linear control valve 66 during ABS control becomes very easy, and the number of controls can be reduced compared to the configuration of the hydraulic brake unit 20 that requires detailed control of the pressure boosting linear control valve 66. In addition to its merits, it can also contribute to the reduction of durability and the extension of life in this respect.

During traction control or vehicle stability control system operation, the accumulator cut valve 78 is opened and the required hydraulic pressure is supplied by controlling the ABS holding valves 51 to 54 and the ABS pressure reducing valves 56 to 59.

FIG. 9 is a modified example of the adjusting unit in each of the above-described embodiments. As an example, FIG. 9 is a partially enlarged view in which only the periphery of the adjustment portion of FIG. 2 is enlarged. In the case of FIG. 9, instead of the orifice, the regulating valve 80, which is a normally closed electromagnetic control valve substantially the same as the separation valve 60, is used as the adjusting section. The regulating valve 80 has a solenoid and a spring that are ON / OFF controlled, and is closed when the solenoid is in a non-energized state. When the regulating valve 80 is in the closed state, the flow of brake fluid to the second flow path 45b is cut off. When the solenoid is energized and the regulating valve 80 is opened, the brake fluid can be circulated in both directions between the first flow path 45a and the second flow path 45b. The control valve 80 has substantially the same flow resistance between the separation valve 60 and the control valve 80, as in the relationship between the separation valve 60 and the orifice 100, preferably the control valve 80 and the separation valve 60 have the same model number. Use a control valve. As a result, it is possible to suppress the occurrence of a control time difference and a pressure difference when the brake fluid is supplied from the booster linear control valve 66, as in the case of using the orifice 100. As a result, even when the "X pipe" is adopted, it is possible to suppress a decrease in the brake feeling during normal braking using the power hydraulic pressure source 30. Further, since the control valve of the same model number can be used for the adjustment valve 80 and the separation valve 60, it is easy to select the parts of the adjustment part. When the adjusting valve 80 is used, it is desirable to provide, for example, a control pressure sensor 82 for confirming the opening / closing of the adjusting valve 80.

By using the regulating valve 80 instead of the orifice 100, it is possible to prevent the brake fluid from flowing back to the reservoir 34 by closing the regulating valve 80 when the pressure boosting linear control valve 66 fails to open. Therefore, it is possible to prevent the accumulator pressure from dropping sharply.

The control for synchronizing the number of closed ABS control valves and the control gain of the booster linear control valve described in Fig. 3 and the delay processing for enabling the control gain of the booster linear control valve described in Fig. 4 are performed. It can also be applied to the case of so-called "front and rear piping" in which the two flow paths sent from the master cylinder unit 27 are connected to the left and right on the front wheel side and the left and right on the rear wheel side, respectively. Even when the control described with reference to FIGS. 3 and 4 is applied to the front and rear piping, hydraulic pressure hunting and control hunting can be suppressed in the same manner as when the control is applied to the X piping.

Further, the flow path system using the regulator 31 and the regulator cut valve 75 used for ABS control described in FIG. 7 can be applied even when the hydraulic brake unit 200 is front and rear piping. Then, as in the case of applying to the "X pipe", it is possible to easily suppress the difference in the response of the hydraulic pressure during ABS control, the decrease in the brake feeling due to the difference in hydraulic pressure, and the generation of operating noise and vibration.

Similarly, the configuration in which the brake fluid from the regulator 31 described in FIG. 8 is supplied to each wheel cylinder 23 via the booster linear control valve 66 is also provided when the hydraulic brake unit 202 is front and rear piping. Applicable. Then, as in the case of applying to "X piping", it is possible to realize the use of a linear control valve with reduced durability, improvement of controllability, reduction of operating noise and vibration, and the like.

Although FIGS. 2, 7, and 8 show an example in which the braking device is a disc brake for all four wheels, for example, the rear wheel side may be a drum brake, or all four wheels may be a drum brake. In this case as well, the same effect as that of each of the above-described embodiments can be obtained, and the cost can be easily reduced by using the drum brake. Further, in the present embodiment, the break control device including the brake regenerative cooperative control is shown as an example, but it can also be applied to a brake-by-wire system not including the brake regenerative cooperative control, and the same effect can be obtained. ..

The present invention is not limited to each of the above-described embodiments, and various modifications such as design changes can be added based on the knowledge of those skilled in the art. The configuration shown in each figure is for explaining an example, and can be appropriately changed as long as the configuration can achieve the same function, and the same effect can be obtained.

According to the present invention, a power hydraulic pressure source and a manual hydraulic pressure source are provided, and the brake feeling is lowered even when a brake device having a braking ability different from that of the front wheel side is mounted on the rear wheel side for cost reduction and miniaturization. Sufficient braking force can be exerted without inviting.

20 Hydraulic brake unit, 27 Master cylinder unit, 30 Power hydraulic source, 35 Accumulator, 36 Pump, 37 1st master piping, 38 2nd master piping, 40 Hydraulic actuator, 51 ~ 54 ABS holding valve, 56 ~ 59 ABS pressure reducing valve, 60 separation valve, 66 booster linear control valve, 67 pressure reducing linear control valve, 70 brake ECU, 100 orifice.