Brake apparatus for vehicle

Vehicle Brake System {BRAKE APPARATUS FOR VEHICLE}

The present invention relates to a vehicle braking system, and more particularly, to a vehicle braking system in which an auxiliary battery charges power supplied from a main battery in advance, and then performs emergency braking with the electric power charged in the auxiliary battery when a fault occurs in the main battery. is about

In general, in hydraulic brakes, when the driver presses the brake pedal, hydraulic pressure is generated in the master cylinder and the hydraulic pressure reaches the caliper on the wheel. At the same time, the brake pad presses the disc in the vertical direction to perform braking.

In the past, it was common to brake a vehicle by generating braking force through such a mechanical hydraulic brake, but recently, an electric-mechanical brake system (hereinafter referred to as 'EMB') that generates braking force by the rotational force of an electric motor has been used. was developed

Since EMB does not use hydraulic pressure, it is eco-friendly, has a faster response speed than hydraulic brakes, and can accurately control the braking force of the wheels through the torque of the motor.

This EMB uses an auxiliary battery in addition to the main battery to perform emergency braking in case of an electrical failure, so as to prepare for an electrical failure caused by the main battery.

However, in the conventional EMB, in order to implement the system architecture in which the auxiliary battery is added, the manufacturing cost is greatly increased due to the auxiliary battery or wiring, various connectors, and a high specification ECU (Electronic Control Unit), and the auxiliary battery is connected. Due to the complicated wiring, there was a problem in that the arrangement and layout of the brake device was also not easy.

The background technology of the present invention is disclosed in Korean Patent Application Laid-Open No. 10-2009-0095774 (2009.09.10).

<p>The present invention has been devised to solve the above problems, and an object of the present invention is to provide an auxiliary battery with power supplied from the main battery in advance, and then, when a fault occurs in the main battery, emergency braking is performed with the power charged in the auxiliary battery. It is to provide a vehicle braking system that performs.</p><p>Another object of the present invention is to provide a vehicle braking system that eliminates the auxiliary battery and its wiring, thereby solving the complexity of a dry type four-wheel EMB-based Brake-by-Wire (BBW) system and reducing the manufacturing cost.</p><p>Another object of the present invention is to provide a vehicle braking system capable of reducing the technical difficulty of BBW development by eliminating an auxiliary battery and complicated wiring. </p>

<p>According to an aspect of the present invention, there is provided a vehicle braking device comprising: an EMB for braking a vehicle by adhering a pad to a disk; a center ECU that controls the EMB according to a braking command; a main battery for supplying power necessary for the operation of the EMB and the center ECU; and an auxiliary battery charged with power supplied from the main battery to supply power to each of the EMB and the center ECU.</p><p>In the present invention, the auxiliary battery is installed in a one-to-one correspondence with the EMB and the center ECU. </p><p>In the present invention, the auxiliary battery is characterized in that it is connected in series with the main battery. </p><p>In the present invention, the center ECU determines whether the vehicle is driving when a braking command is input in a state in which the main battery is defective, and controls the EMB with the power charged in the auxiliary battery when the vehicle is driving. It is characterized by braking the vehicle. </p><p>The center ECU of the present invention determines whether the vehicle is driving when a braking command is input in a state in which the main battery is faulty, and starts the vehicle with the power charged in the auxiliary battery when the vehicle is stopped. characterized by turning it off. </p><p>The present invention further comprises an output unit for warning whether the main battery is defective and the operating state of the vehicle in response to the control signal of the center ECU. </p>

<p>The present invention enables the auxiliary battery to perform emergency braking with the charged power when the power of the main battery is abnormal after the auxiliary battery is charged with power supplied from the main battery. </p><p>The present invention can eliminate the complexity of the dry type four-wheel EMB-based BBW (Brake-by-wire) system by removing the auxiliary battery and its wiring, reduce the manufacturing cost, and reduce the technical difficulty of BBW development. </p>

1 is a block diagram of a vehicle braking system according to an embodiment of the present invention. 2 is a view showing an example of installation of an auxiliary battery according to an embodiment of the present invention. 3 is a view showing another installation example of an auxiliary battery according to an embodiment of the present invention. 4 is a flowchart illustrating an operation process of a vehicle braking system according to an embodiment of the present invention.

Hereinafter, a vehicle braking device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this process, the thickness of the lines or the size of the components shown in the drawings may be exaggerated for clarity and convenience of explanation. In addition, the terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to intentions or customs of users and operators. Therefore, definitions of these terms should be made based on the content throughout this specification.

1 is a block diagram of a vehicle braking system according to an embodiment of the present invention, FIG. 2 is a diagram showing an example of installing an auxiliary battery according to an embodiment of the present invention, and FIG. 3 is an embodiment of the present invention It is a view showing another installation example of the auxiliary battery according to the.

First, the vehicle braking system in this embodiment will be described with the EMB 30 as an example.

The EMB 30 senses the driver's will to brake through a pedal simulator (not shown), and then uses the EMB actuator 32 shown in FIGS. It is a device that regulates the braking pressure of the rear wheel.

Referring to FIG. 1 , a vehicle braking device according to an embodiment of the present invention includes a main battery 10 , an auxiliary battery 40 , a center Electronic Control Unit (ECU) 20 , an EMB 30 , and an output unit 50 . ) is included.

The main battery 10 supplies power necessary for the operation of the center ECU 20 and the EMB 30 and the like.

A plurality of auxiliary batteries 40 are installed, and each is installed in a one-to-one correspondence with the center ECU 20 and the EMB 30 . The auxiliary battery 40 is connected in series with the main battery 10 and is charged with power supplied from the main battery 10 . The power charged in the auxiliary battery 40 is supplied to each of the center ECU 20 and EMB 30 when a fault occurs in the main battery 10 , and the center ECU 20 and EMB 30 are respectively installed in auxiliary batteries. It operates normally with the power of (40).

In particular, the auxiliary battery 40 may be manufactured with various capacities depending on the number of times that power is supplied.

For example, when the emergency braking force is about 0.3 g, the current required for one rear wheel is about 3A and the current required for the front wheel is about 10A, so each auxiliary battery 40 can be manufactured with various capacities based on the above-described power source. have.

Here, the auxiliary battery 40 is connected in series with the main battery 10 as described above and charged when the engine is turned on. In this case, the auxiliary battery 40 is respectively installed inside the center ECU 20 and the EMB 30 or the center ECU 20 ) and may be installed outside the EMB (30).

Referring to FIG. 2 , the EMB 30 is installed on each of the front and rear wheels of the vehicle to brake the vehicle, and the center ECU 20 controls each of the EMB 30 , and the EMB 30 and the center ECU ( 20 is connected to the auxiliary battery 40 to operate with the power of the auxiliary battery 40 .

The EMB 30 is installed on each of the front and rear wheels of the vehicle and brakes the vehicle by bringing the pads into close contact with the disks of each wheel. This EMB 30 includes a wheel ECU 31 and an EMB actuator 32 .

The EMB actuator 32 operates with an electric signal to generate a rotational force, and a motor (not shown), a gear (not shown) provided on a motor shaft (not shown) of the motor and a gear (not shown) rotated to rotate. A power transmitter (not shown) for operating the caliper (not shown) based on the rotational force is provided, and the pad (not shown) presses the wheel disk (not shown) by the operation of the power transmitter. Here, as the EMB actuator 32 , various actuators provided in the EMB 30 may be employed.

The wheel ECU 31 controls the EMB actuator 32 according to a control signal input from the center ECU 20 .

Here, the EMB actuator 32 and the wheel ECU 31 may be installed separately, but are not limited thereto and may be integrated.

In this case, the auxiliary battery 40 is connected in series with the main battery 10 as shown in FIG. 2 and may be installed inside the wheel ECU 31 and the center ECU 20, and the auxiliary battery 40 can be charged with relatively more power than the auxiliary battery 40 provided in the center ECU 20 for driving the EMB actuator 32 .

Referring to FIG. 3 , the auxiliary battery 40 is connected in series with the main battery 10 and may also be installed outside the wheel ECU 31 and the center ECU 20 .

The center ECU 20 controls the EMB 30 according to the braking command. That is, the center ECU 20 monitors the power of the main battery 10 to determine whether the main battery 10 is defective. When a brake command is input in a state in which the main battery 10 is defective, the center ECU 20 determines whether the vehicle is currently driving based on any one or more of the vehicle's wheel speed and whether the engine is started, and the result of the determination When the vehicle is driving, the EMB 30 is controlled with the power charged in the auxiliary battery 40 . Accordingly, the wheel ECU 31 drives the EMB actuator 32 using the power stored in the corresponding auxiliary battery 40 to brake the vehicle. In addition, the center ECU 20 warns the occurrence of a defect in the main battery 10 and the operating state of the vehicle through the output unit 50 .

On the other hand, as a result of the above determination, if the vehicle is stopped, the center EMB 30 turns off the engine start with the power charged in the auxiliary battery 40 , and through the output unit 50 , the main battery 10 is defective and the vehicle is stopped. Alerts the operating state.

The output unit 50 warns whether the main battery 10 is defective and the operating state of the vehicle in response to the control signal of the center ECU 20 . A vehicle cluster or the like may be employed as the output unit 50 .

Hereinafter, an operation process of the vehicle braking system according to an embodiment of the present invention will be described in detail with reference to FIG. 4 .

4 is a flowchart illustrating an operation process of a vehicle braking system according to an embodiment of the present invention.

Referring to FIG. 4 , the center ECU 20 monitors the power of the main battery 10 to determine whether a defect has occurred in the main battery 10 ( S10 ).

If it is determined that a defect has occurred in the main battery 10 as a result of the determination in step S10, the center ECU 20 determines whether a braking command is input (S20).

When a braking command is input as a result of the determination in step S20 , the center ECU 20 determines whether the vehicle is currently driving based on at least one of a wheel speed of the vehicle and whether the engine is started ( S30 ).

If it is determined in step S30 that the vehicle is currently driving, the center ECU 20 brakes the vehicle through the EMB 30 using the power of the auxiliary battery 40 (S40). That is, the center ECU 20 uses the power of the auxiliary battery 40 to input a control signal for vehicle braking to the wheel ECU 31 , and the wheel ECU 31 uses the power of the auxiliary battery 40 . to drive the EMB actuator 32 to brake the vehicle.

In addition, the center ECU 20 warns the occurrence of a defect in the main battery 10 and the operating state of the vehicle through the output unit 50 (S50). That is, the center ECU 20 informs the driver that a defect has occurred in the current main battery 10 and that replacement or repair of the main battery 10 is required through the output unit 50 .

On the other hand, if it is determined in step S30 that the vehicle is stopped, the center ECU 20 uses the power of the auxiliary battery 40 to turn off the engine start (S60).

Then, the center ECU 20 warns the occurrence of a defect in the main battery 10 and the operating state of the vehicle through the output unit 50 (S70). That is, the center ECU 20 informs the driver that the current main battery 10 is defective through the output unit 50 , and thus turns off the vehicle and that replacement or repair of the main battery 10 is required. .

As described above, the present embodiment enables the auxiliary battery 40 to perform emergency braking with the charged power when the power supply of the main battery 10 is abnormal after the auxiliary battery 40 charges the power supplied from the main battery 10 .

In addition, this embodiment eliminates the auxiliary battery 40 and its wiring to solve the complexity of the dry type four-wheel EMB 30-based BBW (Brake-by-wire) system and reduces the manufacturing cost, and the technical difficulty of BBW development to be able to reduce

Although the present invention has been described with reference to the embodiment shown in the drawings, this is merely exemplary, and it is understood that various modifications and equivalent other embodiments are possible by those skilled in the art. will understand Accordingly, the true technical protection scope of the present invention should be defined by the following claims.

10: main battery 20: Center ECU 30: EMB 31: wheel ECU 32: EMB actuator 40: auxiliary battery 50: output unit