Stroke simulator

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention is applied to a brake system having a braking force generator independent of the brake pedal, so-called brake-by-wire, and belongs to the technical field of a stroke simulator that generates a reaction force according to the operation of the brake pedal.

【0002】

[Conventional technology]

Conventionally, as a stroke simulator, for example, the one described in Japanese Patent Application Laid-Open No. 2000-280872 is known.

【0003】

The purpose of this publication is to provide a stroke simulator that can be applied to a braking device that does not use hydraulic pressure, can give a good feeling of operation to the driver, and can reduce the space combined with related equipment. It is directly connected to the brake pedal and gives a reaction force to the operation of the brake pedal, does not require hydraulic pressure, can finely control the reaction force characteristics, and further operates the brake pedal. A technique for applying a reaction force to a brake pedal by an electric actuator that can electrically detect an amount is described.

【0004】

[Problems to be Solved by the Invention]

However, in the conventional stroke simulator, since the reaction force is applied to the brake pedal only by the electric actuator, there are problems as listed below. (1) When operating the brake pedal, the maximum pressing force at the pedal end is 200 kgf, and the maximum pressing speed at the pedal end is 400 mm / sec, so it is extremely large to realize the reaction force during brake operation using only the electric actuator. You will need an electric motor. (2) When an operation to the brake pedal occurs, it is necessary to drive an electric motor with a large rated capacity, and in any case, the electric motor is driven to generate a reaction force, so that power consumption is high. More. (3) Since the pedal reaction force is generated only by the electric actuator, if a failure occurs in the control system of the electric actuator, the pedal movement and pedal reaction force become unnatural, and the brake operation feeling becomes unnatural. It will be damaged.

【0005】

The present invention has been made by paying attention to the above-mentioned problems, and an object of the present invention is to reduce the size of the actuator and save power while having an adjustment function for obtaining a good brake pedal feeling. The purpose of the present invention is to provide a stroke simulator that can ensure the minimum brake operability even if the actuator fails.

【0006】

[Means for solving problems]

In order to achieve the above object, in the invention according to claim 1, in a stroke simulator which is connected to a brake pedal and generates a reaction force according to the operation of the brake pedal, it can move according to the movement of the brake pedal. A piston member, a cylinder member that houses the piston member, a spring member that is housed in the cylinder member and one end of which is supported by the piston member, and a spring member that supports the other end of the spring member. In addition, a movable member that is slidably arranged in the compression and tension directions of the spring member, and an actuator that moves the movable member in the movable direction and has non-reverseness to a reverse input from the movable member. It is characterized by having a control means for controlling the drive of the actuator according to a detection value from the vehicle state detection means for detecting the vehicle state.

【0007】

In the invention according to claim 2, in the stroke simulator according to claim 1, the vehicle state detecting means is a pedal position detecting means for detecting the pedal position of the brake pedal, and the controlling means is a change in the pedal position. It is characterized in that it is a means for controlling the drive of the actuator according to the above.

【0008】

In the invention according to claim 3, in the stroke simulator according to claim 2, the control means does not drive the actuator when the pedal position is equal to or less than a predetermined value, and the pedal position when the pedal position exceeds the predetermined value. It is a means for driving the actuator in the direction of compressing the spring member in response to the increase in the number of spring members.

【0009】

In the invention according to claim 4, in the stroke simulator according to claim 2, the control means once drives an actuator in a direction of pulling the spring member in response to an increase in the pedal position, and then compresses the spring member. It is characterized in that it is a means for driving the actuator in the direction of the spring.

【0010】

In the invention according to claim 5, in the stroke simulator according to claim 1, the vehicle state detecting means is a pedal position detecting means for detecting the pedal position of the brake pedal and a pedal speed detecting means for detecting the pedal speed. The control means is characterized in that it is a means for controlling the drive of the actuator according to changes in the pedal position and the pedal speed.

【0011】

In the invention according to claim 6, in the stroke simulator according to claim 5, when the pedal speed is slow, the control means once drives the actuator in the direction of pulling the spring member in response to an increase in the pedal position. , The means for driving the actuator in the direction of compressing the spring member.

【0012】

In the invention according to claim 7, in the stroke simulator according to claim 5, the control means is a means for driving an actuator in a direction of compressing the spring member in response to an increase in the pedal position when the pedal speed is high. It is characterized by being.

【0013】

In the invention according to claim 8, in the stroke simulator according to claim 5, the spring member is set so as to obtain a characteristic that maximizes the pedal reaction force, and the control means increases the pedal position. On the other hand, the actuator is driven in the direction of pulling the spring member, and the slower the pedal speed, the more the amount of pulling the spring member is increased.

【0014】

In the invention according to claim 9, in the stroke simulator according to claim 1, the vehicle state detecting means is a pedal position detecting means for detecting the pedal position of the brake pedal and a vehicle speed detecting means for detecting the vehicle speed. The control means is characterized in that it is a means for controlling the drive of the actuator according to changes in the pedal position and the vehicle speed.

【0015】

In the invention according to claim 10, in the stroke simulator according to claim 9, when the vehicle speed is low, the control means once drives the actuator in the direction of pulling the spring member in response to an increase in the pedal position. , The means for driving the actuator in the direction of compressing the spring member.

【0016】

In the invention according to claim 11, in the stroke simulator according to claim 9, the control means is a means for driving an actuator in a direction of compressing the spring member in response to an increase in the pedal position when the vehicle speed is high. It is characterized by being.

【0017】

INDUSTRIAL APPLICABILITY

In the invention according to claim 1, when the brake pedal is depressed, the piston member in the cylinder member strokes in response to the movement of the brake pedal, and the stroke of the piston member causes the piston member to move. The spring member interposed between the member is compressed. On the other hand, when the movable member is driven by the actuator, the spring member interposed between the piston member and the movable member is compressed or expanded. That is, the pedal reaction force is applied by the spring member according to the amount of operation on the brake pedal and the amount of control of the movable member.

【0018】

For example, when a spring member having a spring constant k is compressed by driving a movable member, the pedal reaction force F generated by the stroke simulator is F = k when the driver's operation amount is X and the compression amount is Xa. It becomes (X + Xa), and the pedal reaction force becomes larger than when the movable member is fixed. Conversely, when a spring member with a spring constant k is pulled by driving a movable member, the pedal reaction force F generated by the stroke simulator is F = k when the driver's operation amount is X and the tension amount is Xb. It becomes (X-Xb), and the pedal reaction force becomes smaller than when the movable member is fixed. As described above, the brake pedal feeling can be arbitrarily adjusted by controlling and driving the position of the movable member.

【0019】

Further, in the case of a conventional stroke simulator in which the brake pedal is directly driven by an electric actuator, a very large motor is required because the pedal reaction force is handled only by the motor, whereas in the invention according to claim 1, the pedal reaction force is handled. Since the force is shared by the spring member and the actuator, the output of the motor used as a component of the actuator is significantly reduced as compared with the conventional case, and the movable member can be sufficiently driven by a small motor.

【0020】

In the invention according to claim 2, in the control means, the drive of the actuator is controlled according to the change in the pedal position detected by the pedal position detecting means. For example, as in the invention of claim 3, when the pedal position is equal to or less than a predetermined value, the actuator is not driven, and when the pedal position exceeds the predetermined value, the spring member is compressed in response to the increase in the pedal position. In response to an increase in the pedal position, the actuator is once driven in the direction of pulling the spring member, and then the actuator is driven in the direction of compressing the spring member, as in the invention of claim 4. Driven.

【0021】

In this way, since the drive of the actuator is controlled according to the change in the pedal position detected by the pedal position detecting means, not only the magnitude of the reaction force of the brake pedal but also the stroke characteristic of the pedal reaction force is delicate. Can be adjusted.

【0022】

In the invention according to claim 5, in the control means, the drive of the actuator is controlled according to the change of the pedal position detected by the pedal position detecting means and the pedal speed detected by the pedal speed detecting means. For example, as in the invention of claim 6, when the pedal speed is slow, the actuator is once driven in the direction of pulling the spring member in response to the increase in the pedal position, and then the actuator is driven in the direction of compressing the spring member. Alternatively, as in the invention of claim 7, when the pedal speed is high, the actuator is driven in the direction of compressing the spring member in response to the increase in the pedal position.

【0023】

In this way, the drive of the actuator is controlled according to the detected change in pedal position and pedal speed, so when the brake pedal is slowly depressed, the reaction force is reduced and the brake pedal feels soft. On the other hand, when the brake pedal is depressed quickly, the reaction force is increased to give a firm feeling as a brake pedal feeling, and the stroke characteristics of the pedal reaction force are finely adjusted according to the pedal speed. be able to.

【0024】

In the invention according to claim 8, the spring member is set in advance so as to obtain the characteristic of maximizing the pedal reaction force, and the control means pulls the spring member in the direction of increasing the pedal position. As the actuator is driven, the slower the pedal speed, the greater the amount of pulling on the spring member.

【0025】

That is, when the pedal speed is high, the pedal reaction force is generated only by the spring member, and when the pedal speed is in the normal range, the pedal reaction force is generated by controlling only the pulling direction that lowers the reaction force by the spring member. It will be.

【0026】

Therefore, the actuator does not need to generate the maximum torque at the maximum speed, and only needs to generate the maximum torque in the normal range of the pedal speed, so that the actuator can be significantly miniaturized.

【0027】

In the invention according to claim 9, in the control means, the drive of the actuator is controlled according to the change of the pedal position detected by the pedal position detecting means and the vehicle speed detected by the vehicle speed detecting means. For example, as in the invention of claim 10, when the vehicle speed is low, the actuator is once driven in the direction of pulling the spring member in response to the increase in the pedal position, and then the actuator is driven in the direction of compressing the spring member. Or, as in the invention of claim 11, when the vehicle speed is high, the actuator is driven in the direction of compressing the spring member in response to the increase in the pedal position.

【0028】

In this way, the drive of the actuator is controlled according to the detected change in pedal position and vehicle speed. Therefore, when the brake is operated at low speed, the reaction force is reduced and the brake pedal feels soft. On the other hand, when operating the brakes at high speeds, the stroke characteristics of the pedal reaction force can be finely adjusted according to the vehicle speed, such as increasing the reaction force and giving a firm feeling as a pedal feeling. ..

【0029】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments for realizing the stroke simulator in the present invention are described in the first embodiment corresponding to claims 1 to 3, the second embodiment corresponding to claim 4, and claims 5 to 7. A third embodiment corresponding to the above, a fourth embodiment corresponding to claim 8, and a fifth embodiment corresponding to claims 9 to 11 will be described.

【0030】

(First Example) First, the configuration will be described. FIG. 1 is an overall view showing a brake operation unit 2 to which the stroke simulator 1 of the first embodiment is applied. In FIG. 1, 3 is a brake pedal, 4 is a rotating shaft, 5 is a vehicle body, 6 is a support member, and 7 Is the rotating shaft, 8 is the clevis, 12 is the electric motor, 14 is the reducer, 26 is the stroke sensor (pedal position detecting means), 27 is the vehicle speed sensor (vehicle speed detecting means), and 28 is the controller (control means). ..

【0031】

The brake operating unit 2 includes a brake pedal 3 that is stepped on by the driver, a rotating shaft 4 fixed to the brake pedal 3, a support member 6 that rotatably supports the rotating shaft 4 on the vehicle body 5, and the brake. In order to connect the pedal 3 and the stroke simulator 1, the rotating shaft 7 provided on the brake pedal 3, the clevis 8 that converts the locus of the rotating shaft 7 during pedal operation into a linear motion, and the clevis 8 are connected. It is composed of a stroke simulator 1 that generates a reaction force against pedal operation. The stroke simulator 1 receives the reaction force of the brake operation unit 2 by being fixed to the vehicle body 5. Further, an electric motor 12 and a speed reducer 14 are provided on the vehicle body 5 side of the stroke simulator 1.

【0032】

A stroke sensor 26 is attached to the brake pedal 3 to detect the pedal position, and a vehicle speed sensor 27 is attached to the vehicle to detect the vehicle speed. A controller 28 that receives these sensor signals and controls and drives the electric motor 12 of the actuator is electrically arranged between the sensors 26 and 27 and the electric motor 12.

【0033】

The controller 28 is composed of an arithmetic processing device such as a microcomputer, and is arbitrary by calculating the pedal speed from the signal of the stroke sensor 26 and driving and controlling the electric motor 12 based on various signals and internally calculated signals. Generates a pedal reaction force. The arithmetic processing of such basic control is performed according to a predetermined logic in the controller 28, and the control form thereof can be feedback control, open control, or the like known conventionally.

【0034】

FIG. 2 is a cross-sectional view showing the stroke simulator 1 of the first embodiment. In FIG. 2, 9 is a cylinder member, 10 is a pedal side opening, 11 is a piston, 12 is an electric motor, 13 is a motor shaft, and 14 is a motor shaft. Reducer, 15 is the primary gear, 16 is the secondary gear, 17 is the rotating shaft, 18 is the opening on the motor side, 19 is the male screw, 20 is the ball, 21 is the movable member, 22 is the notch, 23 is the protrusion, 24 is a spring member, 25 is a skirt, and 29 is a linear conversion mechanism.

【0035】

The cylinder member 9 is a cylindrical member with both ends closed, a pedal-side opening 10 through which the shaft portion of the piston member 11 is inserted is formed on the front side, and an actuator rotation shaft 17 is inserted on the back side. An opening 18 on the motor side is formed, and a piston member 11, a movable member 21, and a spring member 24 are housed therein.

【0036】

The piston member 11 is a member connected to the clevis 8 and slidable in conjunction with the movement of the brake pedal 3, and the shaft portion 11a on the side connected to the clevis 8 is the pedal side opening of the cylinder member 9. The piston portion 11b protruding from the 10 and housed in the cylinder member 9 is urged by the spring member 24.

【0037】

The spring member 24 is housed in a cylinder member 9, one spring end is supported by the piston portion 11b of the piston member 11, and the other spring end is supported by the skirt portion 25 of the movable member 21. ..

【0038】

The movable member 21 supports the other spring end portion of the spring member 24, and is slidably arranged in the compression and tension directions of the spring member 24 via a linear conversion mechanism 29 with respect to the rotation shaft 17. ..

【0039】

The movable member 21 is moved in the movable direction by the electric motor 12, the speed reducer 14, and the linear conversion mechanism 29, and the rotational force from the electric motor 12 is transmitted, but the reverse input from the movable member 21 by the spring member 24 is received. Therefore, an actuator having a non-reverse property with low transmission efficiency is configured.

【0040】

The speed reducer 14 is composed of a primary gear 15 provided on a motor shaft 13 of an electric motor 12 and a secondary gear 16 meshed with the primary gear 15 and provided on a rotating shaft 17. The rotating shaft 17 of the secondary gear 16 penetrates the motor-side opening 18 of the cylinder member 9 and projects into the cylinder member 9.

【0041】

The linear conversion mechanism 29 is composed of a ball screw for screwing the rotating shaft 17 and the movable member 21, and a stopper structure for restricting the rotation of the movable member 21. The ball screw is inserted between the male screw 19 formed at the tip of the rotating shaft 17, the female screw formed on the movable member 21 arranged on the outer periphery of the male screw 19, and the male screw 19 and the female screw. It has a dressed ball 20 and. The stopper structure has a notch 22 formed in the skirt portion 25 of the movable member 21, and a protrusion 23 fixed to the cylinder member 9 and fitted into the notch 22.

【0042】

The example shown in FIG. 3 is an example in which the electric motor 12 is arranged on the pedal side with respect to the speed reducer 14 to shorten the axial direction, and the example shown in FIG. 4 is an example in which the electric motor 12 is pedal stroked. This is an example in which the speed reducer 14 is arranged in a direction orthogonal to the direction, the type of the speed reducer 14 is different, and the mountability of the electric motor 12 to the vehicle body 5 is improved. The stroke simulator 1 is exactly the same as the example shown in FIG. That is, in the examples shown in FIGS. 2 to 4, only the type of the reduction gear 14 and the arrangement of the electric motor 12 are different, and any of them may be selected depending on the applicable vehicle type and the like.

【0043】

Next, the action will be described.

【0044】

[Pedal reaction force characteristic control process] FIG. 5 is a flowchart showing the flow of the pedal reaction force characteristic control process of the first embodiment executed by the controller 28, and each step will be described below.

【0045】

In step 50, the pedal operation amount P is read by the stroke sensor 26. In the next step 51, it is determined whether or not the pedal operation amount P exceeds the first set value P1 (threshold value for determining whether or not braking is performed). If YES, the process proceeds to step 52, and if NO, the process proceeds to step 52. Return to step 50. In the next step 52, it is determined whether the pedal operation amount P exceeds the second set value P2 (threshold value for determining whether or not the motor is driven). If YES, the process proceeds to step 53, and if NO, the process proceeds to step 53. Return to step 50. In the next step 53, the motor command value X^*(Actuator position to move the movable member 21 in the compression direction) is X^*= Calculated by the equation of the linear function of X1 (P). In the next step 54, the motor command value X^*Is output to the electric motor 12.

【0046】

[Pedal reaction force characteristic control action] When the brake pedal 3 is depressed, first, in the region where the pedal operation amount P is the second set value P2 or less, in the flowchart of FIG. 5, step 50 step 51 step The process of 52 is repeated, the electric motor 12 remains undriven, and the movable member 21 remains fixed in the default position. Therefore, the piston member 11 in the cylinder member 9 strokes in response to the movement of the brake pedal 3, and the stroke of the piston member 11 causes the spring member 24 interposed between the piston member 11 and the movable member 21. It is compressed and a pedal reaction force is applied by the spring member 24 according to the pedal operation amount P.

【0047】

Then, in the region where the pedal operation amount P exceeds the second set value P2, the processes of step 50 step 51 step 52 step 53 step 54 are repeated in the flowchart of FIG. 5, and the electric motor 12 has the pedal operation amount. Driven according to the size of P, the movable member 21 is slid in the direction of compressing the spring member 24 from the initial setting position. Therefore, the pedal reaction force is applied by the spring member 24 according to the pedal operation amount P and the control amount in the compression direction of the movable member 21.

【0048】

That is, the motor command value X^*The actuator position X^*Then, when the pedal operation amount P is paraphrased as the pedal position P, as shown in FIG. 6 (a), the actuator position X is until the pedal position P becomes P1.^*The spring member 24 is left in the initial position where it is neither compressed nor pulled, and when the pedal position P exceeds P1, the actuator position X^*Is controlled to move to the spring compression side in proportion to the pedal position P.

【0049】

Therefore, as shown in FIG. 6 (b), until the pedal position P becomes P1, the pedal reaction force characteristic is obtained by the single spring, and when the pedal position P exceeds P1, the pedal reaction force by the single spring is compressed by the actuator. It becomes a pedal reaction force characteristic to which the pedal reaction force of the minute is added. That is, when the spring member 24 having the spring constant k is compressed by driving the movable member 21, when the driver's pedal operation amount is P and the compression amount is Xa, the pedal reaction force F generated by the stroke simulator 1 is , F = k (P + Xa), and the pedal reaction force is larger than when the movable member 21 is left in a fixed state and is not controlled.

【0050】

Next, the effect will be described.

【0051】

(1) A stroke simulator 1 that is connected to the brake pedal 3 and generates a reaction force in response to the operation of the brake pedal 3 includes a piston member 11, a cylinder member 9, a spring member 24, and a movable member 21. A good brake pedal feeling is achieved because the configuration includes an electric motor 12, a speed reducer 14, a linear conversion mechanism 29, and a controller 28 that controls the drive of the electric motor 12 in response to a sensor signal from the stroke sensor 26. While having the adjustment function to be obtained, the electric motor 12 can be miniaturized and power can be saved, and the minimum brake operability can be ensured even if the actuator system fails.

【0052】

That is, the position of the movable member 21 is controlled and driven so that the pedal reaction force increases when the spring member 24 is compressed by driving the movable member 21, and conversely, the pedal reaction force decreases when the spring member 24 is pulled. Therefore, the brake pedal feeling can be adjusted arbitrarily.

【0053】

Further, in the case of a conventional stroke simulator in which the brake pedal is directly driven by an electric actuator, a very large motor is required because the pedal reaction force is handled only by the motor, whereas the pedal reaction force is the spring member 24 and the movable member. Since the actuator that moves 21 is in charge, the output of the electric motor 12 used as a component of the actuator is significantly reduced as compared with the conventional case, and the movable member 21 can be sufficiently driven by the small electric motor 12.

【0054】

Further, since the small electric motor 12 is driven, power saving is achieved even if the small electric motor 12 is driven at all times when the brake operation is performed. In addition, as in the first embodiment, the movable member 21 is left fixed in the early stroke region of the brake pedal 3, and the movable member 21 is driven and controlled by the actuator only in the late stroke region of the brake pedal 3. Therefore, when the brake operation is performed, it is possible to save power as compared with the conventional stroke simulator in which the electric actuator must be driven at all times.

【0055】

Further, even if it is assumed that the movable member 21 is in a fixed state due to an actuator failure, the pedal pedaling force from the brake pedal 3 is received by the movable member 21 via the spring member 24 due to the irreversible state of the actuator. That is, in the braking operation after the actuator fails, at least the pedal reaction force characteristic of the spring member 24 as a single item can be ensured.

【0056】

(2) Since the drive of the electric motor 12 is controlled according to the change in the pedal operation amount P detected by the stroke sensor 26, not only the magnitude of the reaction force of the brake pedal 3 but also the stroke characteristics of the pedal reaction force are controlled. Can be finely adjusted according to the required performance.

【0057】

(3) When the pedal operation amount P exceeds the second set value P2 without driving the electric motor 12, when the pedal operation amount P exceeds the second set value P2, the spring member responds to the increase in the pedal operation amount P. Since the electric motor 12 is driven in the direction of compressing 24, as shown in FIG. 6 (b), the rate of increase in pedal reaction force with respect to the amount of depression operation is small in the early stroke range of the brake pedal 3, and the brake In the latter stroke range of the pedal 3, it is possible to obtain a pedal reaction force characteristic in which the rate of increase of the pedal reaction force is large with respect to the amount of depression operation.

【0058】

(Second Example) The second embodiment is an example in which the drive control of the electric motor 12 is performed in the early stroke range of the brake pedal 3 with a small amount of depression to further soften the pedal feeling as compared with the first embodiment.

【0059】

Since the configuration of the second embodiment is the same as that of the first embodiment (FIGS. 1 to 4), the illustration and description will be omitted.

【0060】

Next, the action will be described.

【0061】

[Pedal reaction force characteristic control process] FIG. 7 is a flowchart showing the flow of the pedal reaction force characteristic control process of the second embodiment executed by the controller 28, and each step will be described below.

【0062】

In step 70, the pedal operation amount P is read by the stroke sensor 26. In the next step 71, it is determined whether the pedal operation amount P exceeds the first set value P1 (threshold value for determining whether braking is in progress). If YES, the process proceeds to step 72, and if NO, the process proceeds to step 72. Return to step 70. In the next step 72, the motor command value X^*(Actuator position to move the movable member 21 in the compression or pulling direction) is X^*It is calculated by the formula by the quadratic function of = X2 (P). In the next step 73, the motor command value X^*Is output to the electric motor 12.

【0063】

[Pedal reaction force characteristic control action] When the brake pedal 3 is depressed, the processes of step 70 step 71 step 72 step 73 are repeated in the flowchart of FIG. 7, and the electric motor 12 operates the pedal. It is driven according to the size of P.

【0064】

That is, the motor command value X^*The actuator position X^*Then, when the pedal operation amount P is paraphrased as the pedal position P, as shown in FIG. 8 (a), the actuator position X is until the pedal position P becomes P3.^*Is the spring tension side, and when the pedal position P exceeds P3, the actuator position X^*Is set to the spring compression side, and the pedal position P is controlled to move in a quadratic function.

【0065】

Therefore, as shown in Fig. 8 (b), until the pedal position P becomes P3, the pedal reaction force due to the spring alone is subtracted from the pedal reaction force due to the pull by the actuator, and the pedal position P exceeds P3. Then, the pedal reaction force is obtained by adding the pedal reaction force of the compression by the actuator to the pedal reaction force of the spring alone. That is, when the spring member 24 having the spring constant k is pulled by driving the movable member 21, the pedal reaction force F generated by the stroke simulator 1 is calculated when the driver's pedal operation amount is P and the tension amount is Xb. F = k (P-Xb), and the pedal reaction force is smaller than when the movable member 21 is left in a fixed state and is not controlled.

【0066】

Next, the effect will be described.

【0067】

In the stroke simulator 1 of the second embodiment, the following effects can be obtained in addition to the effects of (1) and (2) of the first embodiment.

【0068】

(4) In response to the increase in the pedal operation amount P, the electric motor 12 is once driven in the direction of pulling the spring member 24, and then the electric motor 12 is driven in the direction of compressing the spring member 24. ), The pedal reaction force is suppressed to a small value with respect to the depression operation amount in the early stroke range of the brake pedal 3, and the increase rate of the pedal reaction force with respect to the depression operation amount gradually increases in the late stroke range of the brake pedal 3. It is possible to obtain a pedal reaction force characteristic that increases.

【0069】

(Third Example) The third embodiment is an example in which the drive control of the electric motor 12 is performed according to changes in the pedal operation amount P and the pedal speed ΔP.

【0070】

Since the configuration of the third embodiment is the same as that of the first embodiment (FIGS. 1 to 4), the illustration and description will be omitted.

【0071】

Next, the action will be described.

【0072】

[Pedal reaction force characteristic control process] FIG. 9A is a flowchart showing the flow of the pedal reaction force characteristic control process of the third embodiment executed by the controller 28, and each step will be described below.

【0073】

In step 90, the pedal operation amount P is read by the stroke sensor 26. In the next step 91, the pedal speed ΔP is calculated by calculating the time change amount (differential calculation) of the read pedal operation amount P. In the next step 92, the actuator position map shown in FIG. 10 is loaded. In the next step 93, the motor command value X^*(Actuator position to move the movable member 21 in the compression or pulling direction) is X^*= Calculated by the formula that represents the actuator position map of X3 (P, P). In the next step 94, the motor command value X^*Is output to the electric motor 12.

【0074】

[Pedal reaction force characteristic control action] When the brake pedal 3 is depressed, the process of step 90 step 91 step 92 step 93 step 94 is repeated in the flowchart of FIG. 9 (a), and electricity is applied. The motor 12 is driven according to the magnitude of the pedal operation amount P and the pedal speed ΔP.

【0075】

That is, the motor command value X^*The actuator position X^*In other words, as shown in FIG. 10, in the region where the pedal operation amount P is small and the pedal speed ΔP is slow, the actuator position X^*Is the spring tension side, and when the pedal operation amount P becomes larger than that, the faster the pedal speed ΔP, the more the actuator position X^*Is the spring compression side, and the actuator position X is set with the pedal operation amount P and the pedal speed ΔP as parameters.^*Control is performed to determine.

【0076】

Therefore, as shown in FIG. 9 (b), when the pedal speed is slow, so-called slow braking, for example, until the pedal operation amount P becomes P4, the pedal reaction force of the spring alone and the pedal pulled by the actuator are applied. The characteristic is that the reaction force is reduced, and when the pedal operation amount P exceeds P4, the pedal reaction force is obtained by adding the pedal reaction force of the compression by the actuator to the pedal reaction force of the spring alone. Then, when the pedal speed is high, so-called sudden braking, the pedal reaction force characteristic is obtained by adding the pedal reaction force corresponding to the compression by the actuator to the pedal reaction force by the spring alone regardless of the pedal operation amount P.

【0077】

Next, the effect will be described.

【0078】

In the stroke simulator 1 of the third embodiment, the following effects can be obtained in addition to the effects of (1) and (2) of the first embodiment.

【0079】

(5) Since the drive of the electric motor 12 is controlled according to the change in the pedal operation amount P detected by the stroke sensor 26 and the calculated pedal speed ΔP, the pedal reaction is changed according to the change in the pedal speed ΔP. The stroke characteristics of the force can be finely adjusted.

【0080】

(6) When the pedal speed ΔP is slow, the electric motor 12 is once driven in the direction of pulling the spring member 24 and then the electric motor 12 is driven in the direction of compressing the spring member 24 in response to the increase in the pedal operation amount P. Therefore, as shown in FIG. 9 (b), the pedal reaction force is suppressed to a small value during slow braking when the brake pedal 3 is slowly depressed, and a soft feeling can be obtained as a brake pedal feeling.

【0081】

(7) When the pedal speed ΔP is high, the electric motor 12 is driven in the direction of compressing the spring member 24 in response to the increase in the pedal operation amount P. Therefore, as shown in FIG. 9 (b), the brake pedal At the time of sudden braking when 3 is stepped on quickly, the pedal reaction force becomes large, and you can get a firm feeling as a brake pedal feeling.

【0082】

(Fourth Example) In the fourth embodiment, the spring member 24 is set in advance so as to obtain the characteristic that the pedal reaction force is maximized, and in the controller 28, the spring is generated in response to the increase in the pedal operation amount P. This is an example of driving and controlling the electric motor 12 in the direction of pulling the member 24, and driving and controlling the electric motor 12 to increase the amount of pulling the spring member 24 as the pedal speed ΔP is slower.

【0083】

Since the configuration of the fourth embodiment is the same as that of the first embodiment (FIGS. 1 to 4), the illustration and description will be omitted.

【0084】

Next, the action will be described.

【0085】

[Pedal reaction force characteristic control process] FIG. 11A is a flowchart showing the flow of the pedal reaction force characteristic control process of the fourth embodiment executed by the controller 28, and each step will be described below.

【0086】

In step 110, the pedal operation amount P is read by the stroke sensor 26. In the next step 111, the pedal speed ΔP is calculated by calculating the time change amount (differential calculation) of the read pedal operation amount P. In the next step 112, the actuator position map shown in FIG. 12 is loaded. In the next step 113, the motor command value X^*(Actuator position to move the movable member 21 in the pulling direction) is X^*= Calculated by the formula that represents the actuator position map of X5 (P, P). In the next step 114, the motor command value X^*Is output to the electric motor 12.

【0087】

[Pedal reaction force characteristic control action] When the brake pedal 3 is depressed, the processes of step 110 step 111 step 112 step 113 step 114 are repeated in the flowchart of FIG. 11 (a), and electricity is applied. The motor 12 is driven according to the magnitude of the pedal operation amount P and the pedal speed ΔP.

【0088】

That is, the motor command value X^*The actuator position X^*In other words, as shown in FIG. 12, the actuator position X increases as the pedal operation amount P increases.^*Is the spring tension side, and the slower the pedal speed ΔP, the more the amount of pulling the spring member 24 increases.^*Control is performed to determine.

【0089】

Therefore, as shown in FIG. 11 (b), when the pedal speed is slow, so-called slow braking, the higher the pedal operation amount P, the larger the amount of tension by the actuator (compared to sudden braking) due to the high pedal reaction force due to the single spring. The pedal reaction force characteristics are obtained by reducing the pedal reaction force due to the large amount of tension. When the pedal speed is high, so-called sudden braking, the pedal reaction force due to the large pulling amount by the actuator (smaller pulling amount than during slow braking) is applied as the pedal operation amount P increases from the high pedal reaction force due to the spring alone. The pedal reaction force characteristics are reduced.

【0090】

Next, the effect will be described.

【0091】

In the stroke simulator 1 of the fourth embodiment, the following effects can be obtained in addition to the effects of (1) and (2) of the first embodiment.

【0092】

(8) The spring member 24 is set in advance so as to obtain the characteristic that the pedal reaction force is maximized, and the electric motor 12 in the controller 28 pulls the spring member 24 in the direction of increasing the pedal operation amount P. In addition to controlling the drive of the electric motor 12, the slower the pedal speed ΔP, the more the amount of pulling the spring member 24 is controlled. Therefore, the electric motor 12 used as the actuator should be significantly downsized. Can be done.

【0093】

That is, when the pedal speed ΔP is high, the pedal reaction force is generated only by the spring member 24, and when the pedal speed ΔP is in the normal range, the reaction force by the spring member 24 is reduced by controlling only the pulling direction. This is because the pedal reaction force is generated, and the electric motor 12 used as the actuator does not need to generate the maximum torque at the maximum speed, and only needs to generate the maximum torque in the normal range of the pedal speed ΔP.

【0094】

By the way, in the conventional case where the brake pedal is directly driven by an electric actuator, the required motor specifications are as follows. For example, in a brake pedal with a maximum pedaling force = 200 kgf and a maximum pedal speed = 400 mm / sec, if a linear actuator is attached at a position with a lever ratio of 1/4, the maximum thrust of the linear actuator = 200 x 4 = 800 kgf, maximum speed = 400/4 = 100 mm / sec. Assuming that the linear actuator has a lead of 4.0 mm, the maximum torque of the motor is 800 kgf x 4 mm / 3.14 = 1.02 kgfm, and the maximum rotation speed is 100 mm / sec x 3.14 / 4 mm x 60 sec / min = 4710 rpm. Therefore, the output of the motor is 1.02kgf x 4710rpm x 1.02374 = 4.8kW, which requires a very large motor. On the other hand, according to the stroke simulator 1 of the fourth embodiment, assuming that the maximum pedaling force is 200 kgf and the pedal speed in the normal pedal range is about 40 mm / sec, the same calculation shows that the motor has a rotation speed of 471 rpm and the motor output is 0.4. Reduce to kW.

【0095】

(Fifth Example) The fifth embodiment is an example in which the drive control of the electric motor 12 is performed according to the changes in the pedal operation amount P and the vehicle speed V.

【0096】

Since the configuration of the fifth embodiment is the same as that of the first embodiment (FIGS. 1 to 4), the illustration and description will be omitted.

【0097】

Next, the action will be described.

【0098】

[Pedal reaction force characteristic control process] FIG. 13 (a) is a flowchart showing the flow of the pedal reaction force characteristic control process of the fifth embodiment executed by the controller 28, and each step will be described below.

【0099】

In step 130, the pedal operation amount P is read by the stroke sensor 26. In the next step 131, the vehicle speed V is read by the vehicle speed sensor 27. In the next step 132, the actuator position map shown in FIG. 14 is loaded. In the next step 133, the motor command value X^*(Actuator position to move the movable member 21 in the compression or pulling direction) is X^*= Calculated by the formula that represents the actuator position map of X4 (P, V). In the next step 134, the motor command value X^*Is output to the electric motor 12.

【0100】

[Pedal reaction force characteristic control action] When the brake pedal 3 is depressed, the processes of step 130 step 131 step 132 step 133 step 134 are repeated in the flowchart of FIG. 13 (a), and electricity is applied. The motor 12 is driven according to the magnitude of the pedal operation amount P and the vehicle speed V.

【0101】

That is, the motor command value X^*The actuator position X^*In other words, as shown in FIG. 14, in the region where the pedal operation amount P is small and the vehicle speed V is slow, the actuator position X^*Is the spring tension side, and when the pedal operation amount P becomes larger than that, the faster the vehicle speed V, the more the actuator position X^*Is the spring compression side, and the actuator position X is set with the pedal operation amount P and the vehicle speed V as parameters.^*Control is performed to determine.

【0102】

Therefore, as shown in FIG. 13 (b), when the vehicle speed V is slow, that is, when braking in a so-called low-speed running state, for example, until the pedal operation amount P becomes P5, the pedal reaction force due to the single spring is affected by the actuator. The characteristic is that the pedal reaction force of the tension is reduced, and when the pedal operation amount P exceeds P5, the pedal reaction force is obtained by adding the pedal reaction force of the compression amount by the actuator to the pedal reaction force of the spring alone. Then, when the vehicle speed V is high, that is, when braking in a so-called high-speed running state, the pedal reaction force characteristic is obtained by adding the pedal reaction force of the amount compressed by the actuator to the pedal reaction force of the spring alone regardless of the pedal operation amount P.

【0103】

Next, the effect will be described.

【0104】

In the stroke simulator 1 of the fifth embodiment, the following effects can be obtained in addition to the effects of (1) and (2) of the first embodiment.

【0105】

(9) Since the drive of the electric motor 12 is controlled according to the change in the pedal operation amount P detected by the stroke sensor 26 and the vehicle speed V detected by the vehicle speed sensor 27, the pedal is controlled according to the change in the vehicle speed V. The stroke characteristics of the reaction force can be finely adjusted.

【0106】

(10) When the vehicle speed V is slow, the electric motor 12 is once driven in the direction of pulling the spring member 24 and then the electric motor 12 is driven in the direction of compressing the spring member 24 in response to the increase in the pedal operation amount P. Therefore, as shown in FIG. 13 (b), the pedal reaction force is suppressed to a small value when braking in a low-speed running state such as in an urban area, and a soft feeling can be obtained as a brake pedal feeling.

【0107】

(11) When the vehicle speed V is high, the electric motor 12 is driven in the direction of compressing the spring member 24 in response to the increase in the pedal operation amount P. When braking in the high-speed running state, the pedal reaction force becomes large, and you can get a firm feeling as a brake pedal feeling.

【0108】

(Other Examples) The stroke simulator of the present invention has been described above based on the first to fifth examples, but the specific configuration is not limited to these examples, and claims are made. Design changes and additions are permitted as long as they do not deviate from the gist of the invention according to each claim.

【0109】

For example, in the first to fifth embodiments, an example in which the actuator is composed of the electric motor 12, the speed reducer 14, and the linear conversion mechanism 29 is shown. The actuator is not limited to the configuration shown in the embodiment as long as the actuator has non-reverseness to the reverse input.

【0110】

In the first to fifth embodiments, an example in which the drive of the actuator is controlled according to the pedal operation amount, (pedal operation amount + pedal speed), and (pedal operation amount + vehicle speed) is shown, but as a vehicle state detecting means, , Pedal operation amount detecting means, pedal speed detecting means, detecting means other than vehicle speed detecting means, for example, vehicle deceleration detecting means, etc., and further, for example, (pedal operation amount + pedal speed + vehicle speed), etc. 3 The drive of the actuator may be controlled according to one or more vehicle state information.

[Simple explanation of drawings]

[Figure 1]

It is an overall system diagram which shows the brake operation part to which the stroke simulator of 1st Example was applied.

[Figure 2]

It is sectional drawing which shows the stroke simulator of 1st Example.

[Fig. 3]

It is sectional drawing which shows the other embodiment example in the stroke simulator of 1st Example.

[Fig. 4]

It is sectional drawing which shows the other embodiment example in the stroke simulator of 1st Example.

[Fig. 5]

It is a flowchart which shows the flow of the pedal reaction force control processing performed by the controller of 1st Example.

[Fig. 6]

It is the actuator position characteristic diagram and the pedal reaction force characteristic diagram in the stroke simulator of 1st Example.

[Fig. 7]

It is a flowchart which shows the flow of the pedal reaction force control processing performed by the controller of 2nd Example.

[Fig. 8]

It is the actuator position characteristic diagram and the pedal reaction force characteristic diagram in the stroke simulator of the 2nd Example.

[Fig. 9]

It is the flowchart which shows the flow of the pedal reaction force control processing performed by the controller of 3rd Example, and the pedal reaction force characteristic figure in the stroke simulator of 3rd Example.

[Fig. 10]

It is the actuator position characteristic figure in the stroke simulator of the 3rd Example.

[Fig. 11]

It is the flowchart which shows the flow of the pedal reaction force control processing performed by the controller of 4th Example, and the pedal reaction force characteristic figure in the stroke simulator of 3rd Example.

[Fig. 12]

It is the actuator position characteristic figure in the stroke simulator of 4th Example.

[Fig. 13]

It is the flowchart which shows the flow of the pedal reaction force control processing performed by the controller of 5th Example, and the pedal reaction force characteristic diagram in the stroke simulator of 3rd Example.

[Fig. 14]

It is the actuator position characteristic figure in the stroke simulator of the 5th Example.

[Explanation of symbols]

1 stroke simulator 2 Brake operation unit 3 Brake pedal 4 axis of rotation 5 car body 6 Support member 7 axis of rotation 8 clevis 9 Cylinder member 10 Pedal side opening 11 piston 12 electric motor 13 Motor shaft 14 reducer 15 Primary gear 16 Secondary gear 17 axis of rotation 18 Motor side opening 19 Male screw 20 balls 21 Movable members 22 Notch 23 protrusions 24 Spring member 25 Skirt part 26 Stroke sensor (pedal position detection means) 27 Vehicle speed sensor (vehicle speed detection means) 28 Controller (control means) 29 Linear conversion mechanism