JP2014080146A - Brake control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brake control device for a vehicle which can reduce fluid pressure in each wheel cylinder while reducing numbers of constituting a valve mechanism.SOLUTION: In a brake control device for a vehicle, a wheel cylinder 42FR is connected to a holding valve 61FR in left and right front wheel sides, and a wheel cylinder 42FL is connected to a holding valve 61FL. On the other hand, in the left and right front wheel sides, a wheel cylinder 42RR and a wheel cylinder 42R are connected to one common holding valve 61R. Further, the wheel cylinders 42FR, 42FL, 42RR, 42RL are connected to pressure reduction valves 62FR, 62FL, 62RR, 62RL. In addition, in the left and right front wheel sides, a throttle valve MV1 is provided between a branch point P on an individual channel 51RR and a branch point Q1 on an individual channel 56RR for pressure reduction, and a throttle valve MV2 is provided between a branch point P on an individual channel 51RL and a branch point Q2 on an individual channel 56RL for pressure reduction.

Description

  The present invention relates to a master cylinder that generates hydraulic pressure in response to an operation of a brake pedal by a driver, a power hydraulic pressure source that generates hydraulic pressure by driving a pressurizing pump, and a plurality of solenoid valves that are controlled by electrical signals. And a hydraulic pressure output from the master cylinder or the power hydraulic pressure source via the valve mechanism, and a hydraulic pressure output from the master cylinder or the dynamic hydraulic pressure source via the valve mechanism. The present invention relates to a vehicle brake device including a wheel cylinder that transmits a braking force to a wheel and a control unit that controls the operation of the valve mechanism.

  Conventionally, for example, a brake system disclosed in Patent Document 1 below is known as a brake device for this type of vehicle. This conventional brake system is provided between a common passage to which a power hydraulic pressure source is connected and each brake cylinder provided in each wheel, and allows the common passage and each brake cylinder to communicate with each other. And a pressure reducing valve for connecting and shutting off each brake cylinder and the reservoir. In this conventional brake system, in order to independently control the hydraulic pressure in each brake cylinder, a holding valve is provided for each brake cylinder.

  In addition, as a brake device of this type, for example, a hydraulic pressure control device for an anti-skid device disclosed in Patent Document 2 below is also known. In this conventional hydraulic control device for an anti-skid device, brake fluid pressurized by a hydraulic pump is equally distributed by a flow rate equalizing valve and supplied to the left and right wheel cylinders. Here, the flow rate distribution valve is composed of a piston member slidable inside, a fixed throttle, a cylinder member, a housing member, and left and right lid members inside the piston member, and oil holes formed on the left and right sides of the piston member The oil supply holes formed on the left and right sides of the cylinder member function as a variable throttle in accordance with the stroke of the piston member. As a result, in the brake fluid pressure increasing mode in the skid state, the flow rate equalizing valve operates the piston member due to the pressure difference between the left and right wheel cylinders, and the brake fluid supplied from the hydraulic pump is controlled by a variable throttle made up of each oil supply hole. Are distributed equally to the left and right wheel cylinders. Accordingly, the flow distribution valve distributes the brake fluid supplied from the hydraulic pump equally to the left and right wheel cylinders even when a pressure difference occurs between the left and right wheel cylinders. It is supposed to be the same.

JP 2011-156999 A JP-A-5-330416

  According to the brake system disclosed in Patent Document 1, since a holding valve and a pressure reducing valve are provided for each brake cylinder (wheel cylinder), by opening and closing each of the holding valve and the pressure reducing valve, The hydraulic pressure of the brake cylinder (wheel cylinder) can be controlled to increase or decrease independently of each other. As a result, for example, the braking force can be controlled more finely than the anti-skid device hydraulic pressure control device disclosed in Patent Document 2 in accordance with the running state or behavior change of the vehicle.

  By the way, in the vehicle brake device such as the brake system disclosed in Patent Document 1, since an expensive holding valve is provided for each wheel cylinder, it is possible to finely control the braking force in each wheel. On the other hand, the manufacturing cost becomes high. For this reason, it is eagerly desired to reduce the manufacturing cost by enabling good braking force control, in other words, pressure increase or pressure reduction control in each wheel cylinder.

  The present invention has been made to address the above-described problems, and one of its purposes is a vehicle capable of controlling the hydraulic pressure in each wheel cylinder while reducing the number of valves constituting the valve mechanism. It is to provide a brake device.

  In order to achieve the above object, a vehicle brake device according to the present invention includes a master cylinder, a power hydraulic pressure source, a valve mechanism, a wheel cylinder, and control means.

  The master cylinder generates hydraulic pressure in accordance with the operation of the brake pedal by the driver. The power hydraulic pressure source generates hydraulic pressure by driving a pressure pump. When the power hydraulic pressure source has an accumulator, the hydraulic pressure generated by the pressure pump is accumulated in the accumulator. The valve mechanism is composed of a plurality of electromagnetic valves controlled by electrical signals, and the hydraulic pressure output from the master cylinder or the power hydraulic pressure source is transmitted. The wheel cylinder is configured such that a hydraulic pressure output from the master cylinder or the power hydraulic pressure source is transmitted via the valve mechanism to apply a braking force to the wheel. The control means controls the operation of the valve mechanism.

  In this case, the vehicle brake device may further include a pressure increasing mechanism. The pressure-increasing mechanism is connected to the master cylinder and the power hydraulic pressure source, and uses a hydraulic pressure from the power hydraulic pressure source to achieve a predetermined ratio with respect to the hydraulic pressure from the master cylinder. It generates pressure. Here, the pressure increasing mechanism can be mechanically operated by, for example, a hydraulic pressure output from the master cylinder in accordance with the operation of the brake pedal by the driver.

  The vehicle brake device according to the present invention is characterized in that the valve mechanism is provided upstream of at least a branch point where the hydraulic fluid flowing from the power hydraulic pressure source branches to the plurality of wheel cylinders. A holding valve that is an electromagnetic on-off valve that allows or prohibits transmission of the hydraulic pressure output from the power hydraulic pressure source to the plurality of wheel cylinders, and is provided for each of the plurality of wheel cylinders. And a pressure reducing valve that is an electromagnetic on-off valve that allows or prohibits transmission of hydraulic pressure from the wheel cylinder to the reservoir.

  According to this, the number of expensive holding valves can be reduced by providing a common (single) holding valve to which a plurality of wheel cylinders are connected, and the manufacturing cost of the brake device of the vehicle is effectively reduced. can do. Thus, even when the number of expensive holding valves is reduced, a pressure reducing valve is provided in each of the plurality of wheel cylinders, and the common holding valve and each pressure reducing valve are opened and closed in cooperation with each other. Thus, the hydraulic pressure in each wheel cylinder provided so as to be able to communicate with each other can be appropriately controlled independently.

  In this case, it is preferable that the valve mechanism further includes a throttle provided between the branch point and each of the plurality of wheel cylinders. In this case, more specifically, the throttle can be provided between the branch point and a branch point that branches downstream of the branch point and upstream of the wheel cylinder to the pressure reducing valve. .

  According to these, it is possible to appropriately generate pressure loss between the upstream side and the downstream side of the throttle when the working fluid flows by the throttles provided between the holding valve and the plurality of wheel cylinders. it can. Thereby, in the case where a plurality of wheel cylinders are connected to a common (one) holding valve, a part of the plurality of wheel cylinders is reduced or held and the other part is held or increased. Even in a situation where the hydraulic pressure is controlled, the flow rate of the working fluid flowing through the pressure loss generated by the throttle can be made different, and it is effective that the wheel cylinders having different hydraulic pressures affect each other. Can be prevented. Therefore, the hydraulic pressure of each wheel cylinder can be independently controlled more appropriately.

  In these cases, the control means opens the pressure reducing valves provided in some of the wheel cylinders when reducing the hydraulic pressure in some of the wheel cylinders. In addition, the holding valve can be controlled to be opened. According to this, in the wheel cylinder that needs to be depressurized, the hydraulic pressure can be quickly depressurized by controlling the depressurization valve to the open state. On the other hand, in a wheel cylinder that does not need to be depressurized, there is an effect that the hydraulic pressure is reduced by at least transferring the hydraulic pressure from the power hydraulic pressure source via the holding valve controlled to be opened. Can be suppressed.

  In this case, if a throttle is provided, in a wheel cylinder that needs to be depressurized, the hydraulic fluid flows out to the reservoir via the pressure reducing valve, so that the hydraulic fluid flowing through the throttle is provided. The generated pressure loss increases. For this reason, at least the hydraulic pressure transmitted from the power hydraulic pressure source via the holding valve is hardly consumed (not easily reduced), and the hydraulic pressure in the wheel cylinder that does not need to be reduced is effectively reduced. Can be suppressed. Therefore, even when a plurality of wheel cylinders are connected to a common (one) holding valve, the hydraulic pressure in some wheel cylinders can be reduced independently.

  In these cases, the control means closes the pressure reducing valves provided in some of the wheel cylinders when increasing the hydraulic pressure in some of the wheel cylinders. In addition, the holding valve can be controlled to be opened, and the pressure reducing valve provided in the other wheel cylinder of the plurality of wheel cylinders can be controlled to be opened. According to this, in a wheel cylinder that needs to be increased in pressure, when the pressure reducing valve is controlled to be closed, the hydraulic pressure is at least from the power hydraulic pressure source via the holding valve controlled to be opened. By being transmitted, the hydraulic pressure can be quickly increased. On the other hand, in a wheel cylinder that does not need to be increased in pressure, it is possible to effectively suppress an increase in hydraulic pressure by controlling the pressure reducing valve in the valve open state.

  In this case, if a throttle is provided, in a wheel cylinder that does not need to be pressurized, the hydraulic fluid flows out to the reservoir via the pressure reducing valve, so that the hydraulic fluid flowing through the throttle is provided. The generated pressure loss increases. For this reason, at least the hydraulic pressure transmitted from the power hydraulic pressure source via the holding valve is less likely to be consumed (not easily reduced), and the hydraulic pressure can be accurately transmitted to the wheel cylinder that needs to be increased. The fluid pressure can be reliably increased. Therefore, even when a plurality of wheel cylinders are connected to a common (one) holding valve, the hydraulic pressure in some of the wheel cylinders can be increased independently.

  In these cases, the plurality of wheel cylinders may provide a braking force to the wheels on the left and right rear wheels of the vehicle. More specifically, the plurality of wheel cylinders may be, for example, left and right of the vehicle. A braking force may be applied to the two wheels on the rear wheel side. Further, in these cases, the plurality of wheel cylinders may apply braking force to wheels in a diagonal position relationship between front, rear, left and right in the vehicle.

  According to these, by controlling the hydraulic pressure in the wheel cylinder, it is possible to satisfactorily reduce the influence on the behavior change of the vehicle. In particular, when a plurality of wheel cylinders are selected so as to apply a braking force to the wheels in a physique position relationship between the front, rear, left and right in the vehicle, the behavior change of the vehicle when the braking force is applied to the wheels (for example, the yaw behavior) Can be reduced more satisfactorily.

It is a schematic system diagram of a brake control device in an embodiment of the present invention. It is a schematic sectional drawing which shows the structure of the pressure increase mechanism of FIG. It is a figure for demonstrating the linear control mode by the brake device of the vehicle in embodiment of this invention. It is a figure for demonstrating the backup mode at the time of the liquid leak generation | occurrence | production by the brake device of the vehicle in embodiment of this invention. It is a graph for demonstrating the influence on the other wheel cylinder when depressurizing one wheel cylinder. It is a figure for demonstrating the case where only the right rear-wheel side is pressure-reduced by the brake device of the vehicle in embodiment of this invention. It is a graph for demonstrating the influence on the other wheel cylinder when depressurizing one wheel cylinder by the brake device of the vehicle in embodiment of this invention. It is a figure for demonstrating the case where only the right rear-wheel side is increased with the brake device of the vehicle in embodiment of this invention.

  Hereinafter, a vehicle brake device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic system configuration diagram of a vehicle brake device according to the present embodiment.

  The vehicle brake device according to the present embodiment includes a brake pedal 10, a master cylinder unit 20, a power hydraulic pressure generator 30, a hydraulic pressure control valve device 50, a pressure increase mechanism 80, and a pressure increase mechanism cut valve 90. And a brake ECU 100 for controlling the brake. The brake units 40FR, 40FL, 40RR, 40RL provided on the respective wheels include brake rotors 41FR, 41FL, 41RR, 41RL and wheel cylinders 42FR, 42FL, 42RR, 42RL built in the brake caliper. The brake unit 40 is not limited to a disc brake type for all four wheels. For example, all four wheels may be a drum brake type, or the front wheel may be a disc brake type and the rear wheel may be a drum brake type. It may be good. Further, in the following description, the reference numerals of components provided for each wheel are also given at the end, FR for the right front wheel, FL for the left front wheel, RR for the right rear wheel, and RL for the left rear wheel. However, when it is not particularly necessary to specify the wheel position, the last symbol is omitted.

  The wheel cylinders 42FR, 42FL, 42RR, and 42RL are connected to the hydraulic pressure control valve device 50 so that the hydraulic pressure of the hydraulic fluid (brake fluid) supplied from the device 50 is transmitted. The brake pads are pressed against the brake rotors 41FR, 41FL, 41RR, and 41RL that rotate together with the wheels by the hydraulic pressure supplied from the hydraulic control valve device 50 to apply braking force to the wheels.

  The master cylinder unit 20 includes a master cylinder 21 and a reservoir 22. The master cylinder 21 is a tandem type having pressurizing pistons 21a and 21b, and a master cylinder pressure Pmc_FR having a predetermined boost ratio with respect to the pedal depression force input in accordance with the depression operation of the brake pedal 10. , Pmc_FL is generated. A reservoir 22 for storing hydraulic fluid (brake fluid) is provided at the top of the master cylinder 21. Thus, in the master cylinder 21, when the depression operation of the brake pedal 10 is released and the pressure pistons 21a and 21b are retracted, the pressure chambers 21a1 and 21b1 formed by the pressure pistons 21a and 21b are It communicates with the reservoir 22. The pressurizing chambers 21a1 and 21b1 communicate with the hydraulic pressure control valve device 50 via master pressure pipes 11 and 12, which will be described later.

  The power hydraulic pressure generator 30 is a power hydraulic pressure source (power supply), and includes a pressurizing pump 31 and an accumulator 32. The pressurizing pump 31 has its suction port connected to the reservoir 22, its discharge port connected to the accumulator 32, and pressurizes the hydraulic fluid by driving the motor 33. The accumulator 32 converts the pressure energy of the hydraulic fluid pressurized by the pressurizing pump 31 into pressure energy of a sealed gas such as nitrogen and stores it. The accumulator 32 is connected to a relief valve 23 provided in the master cylinder unit 20. The relief valve 23 opens when the pressure of the hydraulic fluid rises above a predetermined pressure, and returns the hydraulic fluid to the reservoir 22.

  As described above, the brake device of the vehicle is a master that applies the hydraulic pressure using the pedal depression force input through the brake pedal 10 by the driver as the hydraulic pressure source that applies the hydraulic pressure of the hydraulic fluid to the wheel cylinder 42. A cylinder 21 and a power hydraulic pressure generator 30 that applies a hydraulic pressure independently of the master cylinder 21 are provided. In the brake device of the vehicle, the master cylinder 21 (more specifically, the pressurizing chambers 21a1, 21b1) and the power hydraulic pressure generator 30 are liquidated via the master pressure pipes 11, 12 and the accumulator pressure pipe 13, respectively. It is connected to the pressure control valve device 50. The reservoir 22 is connected to the hydraulic control valve device 50 via the reservoir pipe 14. In the following description, regarding the master pressure pipe 12, the upstream side (input side) of the pressure increase mechanism 80 is referred to as a master pressure pipe 12a, and the downstream side (output side) of the pressure increase mechanism 80 is referred to as a master pressure. These are distinguished by being referred to as piping 12b.

  Here, a stroke simulator 70 is connected to the master pressure pipe 12a via a simulator flow path 71 and a simulator cut valve 72 which is a normally closed electromagnetic on-off valve. The stroke simulator 70 includes a piston 70a and a spring 70b. When the simulator cut valve 72 is in an open state, the stroke simulator 70 introduces an amount of hydraulic fluid corresponding to the brake operation amount of the brake pedal 10 by the driver. The stroke simulator 70 allows the driver to operate the brake pedal 10 by displacing the piston 70a against the urging force of the spring 70b in accordance with the introduction of the working fluid. A reaction force corresponding to the amount of operation is generated to improve the brake operation feeling of the driver. Needless to say, the stroke simulator 70 can be connected to the master pressure pipe 11.

  The hydraulic control valve device 50 is a mainstream that communicates the four individual flow paths 51FR, 51FL, 51RR, 51RL connected to the wheel cylinders 42FR, 42FL, 42RR, 42RL and the individual flow paths 51FR, 51FL, 51RR, 51RL. The passage 52, the master pressure passages 53 and 54 connecting the individual passages 51FR and 51FL and the master pressure pipes 11 and 12 (12b), and the accumulator pressure passage 55 connecting the main passage 52 and the accumulator pressure pipe 13 are provided. I have. Here, the master pressure channels 53 and 54 and the accumulator pressure channel 55 are respectively connected in parallel to the main channel 52.

  The individual flow paths 51FR and 51FL are respectively provided with holding valves 61FR and 61FL in the middle thereof, and the individual flow paths 51RR and 51RL are provided with one (common) holding valve 61R in the upstream part thereof. The holding valve 61FR provided in the brake unit 40FR on the right front wheel side is normally closed and electromagnetically opened and maintained only when the solenoid is energized, and is maintained in the closed state by the biasing force of the spring. It is a valve. On the other hand, the holding valve 61FL provided in the brake unit 40FL on the left front wheel side is kept normally open by the biasing force of the spring when the solenoid is not energized and is closed only when the solenoid is energized. It is an electromagnetic on-off valve. Also, the holding valve 61R common to both the left and right rear wheel brake units 40RR and 40RL is kept closed by the biasing force of the spring when the solenoid is not energized, and is opened only when the solenoid is energized. This is a normally closed electromagnetic on-off valve.

  Each holding valve 61 allows the hydraulic pressure to be transmitted by flowing the hydraulic fluid from the main flow path 52 to the respective wheel cylinders 42 through the individual flow paths 51 in the open state, thereby allowing the wheel cylinder pressure (to a control pressure Px described later). Pressure). On the other hand, each holding valve 61 shuts off the flow of hydraulic fluid from the main flow path 52 to each wheel cylinder 42 via the individual flow path 51 in the closed state, and from the wheel cylinder 42 via the individual flow path 51. By blocking the flow of the hydraulic fluid to the passage 52, the transmission of the hydraulic pressure is prohibited, and the wheel cylinder pressure (control pressure Px) is maintained.

  The individual flow paths 51FR, 51FL, 51RR, and 51RL are connected to pressure-reducing individual flow paths 56FR, 56FL, 56RR, and 56RL on the upstream side of the wheel cylinders 42FR, 42FL, 42RR, and 42RL, respectively. Each decompression individual channel 56 is connected to a reservoir channel 57. The reservoir channel 57 is connected to the reservoir 22 via the reservoir pipe 14. Each individual pressure reducing flow path 56FR, 56FL, 56RR, 56RL is provided with a pressure reducing valve 62FR, 62FL, 62RR, 62RL in the middle thereof. The pressure reducing valves 62FR, 62FL, and 62RR are normally closed electromagnetic on-off valves that maintain a valve closed state by a biasing force of a spring when the solenoid is not energized and are opened only when the solenoid is energized. The pressure reducing valve 62RL is a normally open electromagnetic on-off valve that maintains a valve open state by a biasing force of a spring when the solenoid is not energized and is closed only when the solenoid is energized. Each pressure reducing valve 62 allows the hydraulic pressure to be transmitted by allowing the hydraulic fluid to flow from the wheel cylinder 42 to the reservoir flow path 57 via the pressure reducing individual flow path 56 in the open state, thereby reducing the wheel cylinder pressure. By blocking the hydraulic fluid from flowing through the reservoir channel 57 in the closed state, the hydraulic pressure is prohibited from being transmitted and the wheel cylinder pressure is maintained.

  Furthermore, in the present embodiment, the individual flow paths 51RR and 51RL on the left and right rear wheel sides are respectively downstream of the holding valve 61R, more specifically, downstream of the branch point P of the individual flow paths 51RR and 51RL. In addition, throttle valves MV1 and MV2 as throttles are provided upstream of the branch points Q1 and Q2 of the individual pressure reducing flow paths 56RR and 56RL. The throttle valves MV1 and MV2 are, for example, fixed throttle valves (orifices), and appropriately adjust the flow rate of the hydraulic fluid in the individual flow paths 51RR and 51RL.

  Master cut valves 63 and 64 are provided in the middle portions of the master pressure channels 53 and 54, respectively. The master cut valves 63 and 64 are normally open electromagnetic on-off valves that are kept open by the biasing force of the spring when the solenoid is not energized and are closed only when the solenoid is energized. By providing the master cut valves 63 and 64 in this way, when the master cut valves 63 and 64 are in the closed state, the connection between the master cylinder 21 (and the pressure increasing mechanism 80) and the wheel cylinders 42FR and 42FL is established. When the master cut valves 63 and 64 are open, the master cylinder 21 (and the pressure increase mechanism 80) and the wheel cylinders 42FR and 42FL are connected when the flow of the hydraulic fluid is prohibited by being blocked. The distribution of hydraulic fluid is allowed.

  The accumulator pressure channel 55 is provided with a pressure-increasing linear control valve 65A in the middle part thereof. Further, a pressure reducing linear control valve 65B is provided between the main channel 52 and the reservoir channel 57 to which the accumulator pressure channel 55 is connected. The pressure-increasing linear control valve 65A and the pressure-decreasing linear control valve 65B maintain the closed state by the biasing force of the spring when the solenoid is not energized, and the valve opening increases as the energization amount (current value) to the solenoid increases. This is a normally closed electromagnetic linear control valve. Although the detailed description of the pressure-increasing linear control valve 65A and the pressure-decreasing linear control valve 65B is omitted, a spring force that the built-in spring urges the valve body in the valve closing direction and a relatively high-pressure hydraulic fluid Expressed as the difference between the differential pressure at which the valve body is urged in the valve opening direction by the differential pressure between the circulating primary side (inlet side) and the secondary side (exit side) through which the relatively low pressure hydraulic fluid flows. The valve closing state is maintained by the valve closing force.

  On the other hand, the pressure-increasing linear control valve 65A and the pressure-decreasing linear control valve 65B are used when the electromagnetic attraction force acting in the direction of opening the valve element generated by energizing the solenoid exceeds the valve closing force, that is, the electromagnetic attraction When force> valve closing force (= spring force-differential pressure) is satisfied, the valve is opened at an opening corresponding to the balance of the force acting on the valve element. Accordingly, the pressure-increasing linear control valve 65A and the pressure-decreasing linear control valve 65B control the differential pressure, that is, the primary side (inlet side) and the secondary side (outlet side) by controlling the energization amount (current value) to the solenoid. The opening according to the differential pressure can be adjusted. In the following description, when there is no need to distinguish between the pressure-increasing linear control valve 65A and the pressure-decreasing linear control valve 65B, they are also simply referred to as the linear control valve 65.

  The pressure increasing mechanism 80 in the present embodiment increases (servo) the master cylinder pressure Pmc_FL output from the pressurizing chamber 21b1 of the master cylinder 21 and supplies it to the wheel cylinder 42FL. Here, the pressure increasing mechanism 80 will be described. As the pressure increasing mechanism 80, any structure that can increase (servo) the master cylinder pressure Pmc_FL by a mechanical operation similar to that described later can be used. Further, in the following, a case where the pressure increasing mechanism 80 is provided in the master pressure pipe 12 will be described, but it is needless to say that the pressure increasing mechanism 80 can be provided in the master pressure pipe 11.

  As shown in FIG. 2, the pressure-increasing mechanism 80 includes a housing 81 and a stepped piston 82 that is liquid-tight and slidably fitted to the housing 81, and has a large diameter on the large-diameter side of the stepped piston 82. A side chamber 83 is provided, and a small-diameter side chamber 84 is provided on the small-diameter side. The small-diameter side chamber 84 can communicate with the high-pressure chamber 85 connected to the accumulator 32 of the power hydraulic pressure generator 30 via the high-pressure supply valve 86 and the valve seat 87. As shown in FIG. 2, the high pressure supply valve 86 is pressed against the valve seat 87 by the biasing force of the spring in the high pressure chamber 85 and is a normally closed valve.

  The small-diameter side chamber 84 is provided with a valve opening member 88 facing the high-pressure supply valve 86, and a spring is disposed between the valve opening member 88 and the stepped piston 82. The biasing force of the spring acts in a direction in which the valve opening member 88 is separated from the stepped piston 82. As shown in FIG. 2, a return spring is provided between the step portion of the stepped piston 82 and the housing 81 to urge the stepped piston 82 in the backward direction. A stopper (not shown) is provided between the stepped piston 82 and the housing 81 so as to regulate the forward end position of the stepped piston 82.

  Further, the stepped piston 82 is formed with a communication passage 89 that allows the large-diameter side chamber 83 and the small-diameter side chamber 84 to communicate with each other. The communication passage 89 allows the large-diameter side chamber 83 and the small-diameter side chamber 84 to communicate with each other while being separated from the valve opening member 88 as shown in FIG. Then, when it comes into contact with the valve opening member 88, it is blocked. With this configuration, the pressure intensifying mechanism 80 operates as a mechanical pressure intensifier (mechanical valve).

  As shown in FIGS. 1 and 2, the high pressure chamber 85 and the power hydraulic pressure generator 30 are connected by a high pressure supply passage 15, and a power hydraulic pressure is generated in the high pressure supply passage 15 together with a pressure increase mechanism cut valve 90. A check valve is provided which allows the flow of hydraulic fluid from the device 30 to the high pressure chamber 85 and prevents reverse flow. The pressure-increasing mechanism cut valve 90 is a normally-open electromagnetic open / close valve that maintains a valve open state by a biasing force of a spring when the solenoid is not energized and is closed only when the solenoid is energized.

  Thus, by providing the pressure increase mechanism cut valve 90, the power hydraulic pressure generator 30 (more specifically, the pressure pump 31 or the accumulator 32) and the high pressure chamber 85 are closed when the solenoid is energized. The transmission of hydraulic pressure between them, specifically, the flow of hydraulic fluid is interrupted. Therefore, even if liquid leakage occurs in the pressure increasing mechanism 80 due to a sealing abnormality or the like, the high pressure hydraulic fluid is discharged from the accumulator 32 by maintaining the pressure increasing mechanism cut valve 90 in the closed state. Backflow to the master cylinder 21 via the pressure increase mechanism 80 and the master pressure pipe 12a can be reliably prevented. Further, since the communication (connection) between the accumulator 32 and the high-pressure chamber 85 of the pressure-increasing mechanism 80 via the high-pressure supply passage 15 is interrupted, liquid leakage has occurred in the pressure-increasing mechanism 80 due to an abnormality in the sealing property. Even in this case, a decrease (consumption) of the hydraulic pressure in the accumulator 32 (corresponding to an accumulator pressure Pacc described later) can be reliably prevented.

  Further, by providing a check valve in the high pressure supply passage 15, when the hydraulic pressure of the power hydraulic pressure generator 30 (more specifically, the accumulator 32) is higher than the hydraulic pressure of the high pressure chamber 85, the power hydraulic pressure generator is provided. The hydraulic fluid is allowed to flow from 30 to the high pressure chamber 85, but when the hydraulic pressure of the power hydraulic pressure generator 30 is equal to or lower than the hydraulic pressure of the high pressure chamber 85, the valve is closed and bidirectional flow is prohibited. . Therefore, when the pressure increase mechanism cut valve 90 is in the open state, even if liquid leakage occurs in the power hydraulic pressure generator 30, the hydraulic fluid flows back from the high pressure chamber 85 to the power hydraulic pressure generator 30. It is possible to prevent the decrease in the hydraulic pressure of the small-diameter side chamber 84.

  The master pressure pipe 12a and the large-diameter side chamber 83 of the pressure-increasing mechanism 80 are connected by the pilot passage 16, and the pilot-pressure passage 16 and the output side of the pressure-increasing mechanism 80 (that is, the master pressure pipe communicating with the small-diameter side chamber 84). 12b) is provided with a bypass passage 17 that bypasses and connects the pressure increasing mechanism 80. The bypass passage 17 allows a flow of hydraulic fluid from the pilot passage 16 (master pressure pipe 12a) to the master pressure pipe 12b on the output side of the pressure increasing mechanism 80, and prevents a reverse flow. Is provided. Further, a reservoir passage 18 is provided between a space formed by the stepped housing 81 of the stepped piston 82 and the reservoir pipe 14 communicating with the reservoir 22.

  Hereinafter, the operation of the pressure increasing mechanism 80 will be briefly described. In the pressure increasing mechanism 80, the hydraulic fluid (master cylinder pressure Pmc_FL) is transferred from the master cylinder 21 through the master pressure pipe 12a and the pilot passage 16 to the large-diameter side chamber 83. ) Is supplied to the small-diameter side chamber 84 via the communication path 89. The forward force acting on the stepped piston 82 with the supply of the hydraulic fluid (master cylinder pressure Pmc_FL) (the forward force due to the master cylinder pressure Pmc_FL acting on the large-diameter side chamber 83) is greater than the biasing force of the return spring. When it becomes larger, the stepped piston 82 moves forward. As a result, when the stepped piston 82 contacts the valve opening member 88 and the communication passage 89 is blocked, the hydraulic pressure in the small-diameter side chamber 84 increases as the stepped piston 82 advances, and the pressurized hydraulic fluid is increased. (That is, servo pressure) is output to the master pressure channel 53 of the hydraulic pressure control valve device 50 via the master pressure pipe 12b.

  Further, when the high pressure supply valve 86 is switched to the open state by the advancement of the valve opening member 88, the high pressure hydraulic fluid is supplied from the high pressure chamber 85 to the small diameter side chamber 84, and the hydraulic pressure in the small diameter side chamber 84 becomes higher. In this case, the pressure-increasing mechanism cut valve 90 is opened, and the hydraulic fluid pressure (accumulator pressure Pacc) stored in the accumulator 32 of the power hydraulic pressure generator 30 is greater than the hydraulic pressure in the high-pressure chamber 85. If it is higher, the hydraulic pressure of the accumulator 32 (accumulator pressure Pacc) is supplied to the high pressure chamber 85 via the check valve of the high pressure supply passage 15 and supplied to the small diameter side chamber 84. In the stepped piston 82, the hydraulic pressure of the large-diameter side chamber 83, that is, the master cylinder pressure Pmc_FL, acts on the large-diameter side (master cylinder pressure Pmc_FL × pressure receiving area) and on the small-diameter side (servo pressure × The output is adjusted to a size that balances the pressure receiving area. Therefore, it can be said that the pressure increasing mechanism 80 is a mechanical booster mechanism.

  On the other hand, when the pressure-increasing mechanism cut valve 90 is opened and the hydraulic pressure in the accumulator 32 (accumulator pressure Pacc) is equal to or lower than the hydraulic pressure in the high-pressure chamber 85, the reverse provided in the high-pressure supply passage 15 is provided. Since the stop valve prevents the flow of hydraulic fluid between the accumulator 32 and the high pressure chamber 85, the stepped piston 82 cannot advance further. Further, the stepped piston 82 may not be able to move forward by contacting the stopper. In this state, when the master cylinder pressure Pmc_FL supplied from the master cylinder 21 increases and becomes higher than the hydraulic pressure in the small-diameter side chamber 84, the master cylinder pressure Pmc_FL is supplied to the master pressure pipe 12b through the bypass passage 17 and the check valve. Is done.

  The power hydraulic pressure generating device 30 and the hydraulic pressure control valve device 50 are driven and controlled by a brake ECU 100 as control means. The brake ECU 100 includes a microcomputer including a CPU, a ROM, a RAM, and the like as main components, and includes a pump drive circuit, an electromagnetic valve drive circuit, an interface for inputting various sensor signals, a communication interface, and the like. All the electromagnetic on-off valves 61 to 64, 72, 90 and the linear control valve 65 provided in the hydraulic control valve device 50 are all connected to the brake ECU 100, and are opened and closed and opened by a solenoid drive signal output from the brake ECU 100. (In the case of the linear control valve 65) is controlled. The motor 33 provided in the power hydraulic pressure generator 30 is also connected to the brake ECU 100 and is driven and controlled by a motor drive signal output from the brake ECU 100.

  The hydraulic control valve device 50 is provided with an accumulator pressure sensor 101, master cylinder pressure sensors 102 and 103, and a control pressure sensor 104 as hydraulic pressure detection means. The accumulator pressure sensor 101 is the hydraulic fluid pressure in the accumulator pressure channel 55 on the power hydraulic pressure generator 30 side (upstream side) from the pressure-increasing linear control valve 65A, that is, the accumulator pressure channel 55 is connected via the accumulator pressure pipe 13. Therefore, the accumulator pressure Pacc is detected. The accumulator pressure sensor 101 outputs a signal representing the detected accumulator pressure Pacc to the brake ECU 100. Thereby, the brake ECU 100 reads the accumulator pressure Pacc in a predetermined cycle, and when the accumulator pressure Pacc falls below a preset minimum set pressure, the brake ECU 100 drives the motor 33 to pressurize the hydraulic fluid by the pressurizing pump 31, Control is performed so that the accumulator pressure Pacc is always maintained within the set pressure range.

  The master cylinder pressure sensor 102 is hydraulic fluid pressure in the master pressure channel 53 on the master cylinder 21 side (upstream side) from the master cut valve 63, that is, the master pressure channel 53 is connected to the pressurizing chamber via the master pressure pipe 11. Since it communicates with 21a1, the master cylinder pressure Pmc_FR is detected. The master cylinder pressure sensor 103 is a hydraulic fluid pressure in the master pressure channel 54 on the master cylinder 21 side (upstream side) from the master cut valve 64, that is, the master pressure channel 54 is pressurized through the master pressure pipe 12. Since it communicates with 21b1, the master cylinder pressure Pmc_FL is detected. Master cylinder pressure sensors 102 and 103 output signals representing detected master cylinder pressures Pmc_FR and Pmc_FL to brake ECU 100. The control pressure sensor 104 outputs a signal representing the control pressure Px (corresponding to the wheel cylinder pressure in each wheel cylinder 42), which is the hydraulic pressure of the hydraulic fluid in the main flow path 52, to the brake ECU 100.

  In addition, a stroke sensor 105 provided on the brake pedal 10 is connected to the brake ECU 100. The stroke sensor 105 outputs a signal representing the pedal stroke Sm, which is the amount of depression (operation amount) of the brake pedal 10 by the driver, to the brake ECU 100. A wheel speed sensor 106 is connected to the brake ECU 100. The wheel speed sensor 106 detects a wheel speed Vx that is the rotational speed of the left and right front and rear wheels, and outputs a signal representing the detected wheel speed Vx to the brake ECU 100. Further, the brake ECU 100 is connected to an indicator 107 that notifies the driver of an abnormality that has occurred in the vehicle brake device. The indicator 107 notifies the abnormality that has occurred under the control of the brake ECU 100.

  Next, brake control executed by the brake ECU 100 will be described. The brake ECU 100 adjusts the hydraulic pressure output from the power hydraulic pressure generator 30 (more specifically, the accumulator pressure Pacc) by the linear control valve 65 and transmits the pressure to the wheel cylinders 42 (4S mode). The brake control is performed in two control modes including a backup mode (2S mode) in which master cylinder pressures Pmc_FR and Pmc_FL generated in the master cylinder 21 are transmitted to the wheel cylinders 42FR and 42FL in accordance with at least the pedal depression force applied to the brake pedal 10 by the driver. Is selectively executed.

  First, in the linear control mode, as shown in FIG. 3, the brake ECU 100 maintains the normally open master cut valves 63 and 64 in a closed state by energizing the solenoid, and sets the simulator cut valve 72 to the solenoid. Keep the valve open by energization. The brake ECU 100 keeps the normally-open pressure-increasing mechanism cut valve 90 closed by energizing the solenoid. In the linear control mode, the brake ECU 100 controls the solenoid energization amount (current value) of the pressure-increasing linear control valve 65A and the pressure-decreasing linear control valve 65B, and controls the opening according to the energization amount. The brake ECU 100 maintains the normally open holding valve 61FL in the open state and maintains the normally closed holding valves 61FR and 61R in the open state by energizing the solenoid. Further, the brake ECU 100 maintains the normally closed pressure reducing valves 62FR, 62FL, 62RR in the closed state and maintains the normally opened pressure reducing valve 62RL in the closed state by energizing the solenoid.

  In this way, by controlling the open state or the closed state of each valve constituting the hydraulic pressure control valve device 50, the master cut valves 63 and 64 are both maintained in the closed state in the linear control mode. Therefore, the master cylinder pressures Pmc_FR and Pmc_FL output from the master cylinder 21 are not transmitted to the wheel cylinders 42FR and 42FL. Further, since the pressure increase mechanism cut valve 90 is maintained in the closed state, the accumulator pressure Pacc output from the pressure pump 31 or the accumulator 32 of the power hydraulic pressure generator 30 is not transmitted to the pressure increase mechanism 80.

  On the other hand, the accumulator pressure Pacc output from the power hydraulic pressure generator 30 is regulated by the pressure-increasing linear control valve 65A and the pressure-decreasing linear control valve 65B in which the solenoid is in the energization control state, and is in the main flow path 52 and the valve open state. It is transmitted to the four-wheel wheel cylinder 42 via the holding valves 61FR, 61FL, 61R. In this case, if the pressure reducing valve 62 is maintained in the closed state, the wheel cylinder pressure in each wheel cylinder 42 is the same for the four wheels, and becomes the control pressure Px detected by the control pressure sensor 104.

  By the way, the vehicle provided with the vehicle brake device according to the present embodiment includes, for example, an electric vehicle (EV) including a traveling motor driven by a battery power source, and an internal combustion engine in addition to the traveling motor. The hybrid vehicle (HV) and the hybrid vehicle (HV) can be a plug-in hybrid vehicle (PHV) capable of charging a battery using an external power source. In such a vehicle, it is possible to generate regenerative braking by generating a braking force by generating power by converting the rotational energy of the wheels into electric energy by a traveling motor and regenerating the generated power in a battery. When performing such regenerative braking, regenerative braking and hydraulic braking are performed by generating in the vehicle braking device a braking force obtained by removing the braking force due to regeneration from the total braking force required for braking the vehicle. Brake regenerative cooperative control can be performed in combination.

  Specifically, the brake ECU 100 starts the brake regeneration cooperative control in response to the braking request. The braking request should be applied to the vehicle, for example, when the driver depresses the brake pedal 10 (hereinafter simply referred to as “brake operation”) or when there is a request to activate the automatic brake. Occurs when. Here, the automatic brake may be operated in traction control, vehicle stability control (vehicle behavior stability control), inter-vehicle distance control, collision avoidance control, and the like, and when these control start conditions are satisfied, a braking request is issued. Occur.

  Upon receiving a braking request, the brake ECU 100 detects the brake operation amount by the master cylinder pressure Pmc_FR detected by the master cylinder pressure sensor 102, the master cylinder pressure Pmc_FL detected by the master cylinder pressure sensor 103, and the stroke sensor 105. At least one of the pedal strokes Sm is acquired, and a target braking force that increases as the master cylinder pressure Pmc_FR, the master cylinder pressure Pmc_FL and / or the pedal stroke Sm increases is calculated. For the brake operation amount, instead of obtaining the master cylinder pressure Pmc_FR, the master cylinder pressure Pmc_FL and / or the pedal stroke Sm, for example, a pedal force sensor for detecting the pedal depression force with respect to the brake pedal 10 is provided, and the pedal depression force is provided. It is also possible to calculate the target braking force based on the above.

  The brake ECU 100 transmits information representing the calculated target braking force to the hybrid ECU (not shown). The hybrid ECU calculates a braking force generated by power regeneration from the target braking force, and transmits information representing the regenerative braking force, which is the calculation result, to the brake ECU 100. Thus, the brake ECU 100 calculates a target hydraulic braking force that is a braking force that should be generated by the brake device of the vehicle by subtracting the regenerative braking force from the target braking force. Here, the regenerative braking force generated by the power regeneration performed by the hybrid ECU not only varies depending on the rotation speed of the motor, but also varies depending on the regenerative power control depending on the state of charge (SOC) of the battery. . Accordingly, an appropriate target hydraulic braking force can be calculated by subtracting the regenerative braking force from the target braking force.

  The brake ECU 100 calculates the target hydraulic pressure of each wheel cylinder 42 corresponding to the target hydraulic pressure braking force based on the calculated target hydraulic pressure braking force, and provides feedback so that the wheel cylinder pressure becomes equal to the target hydraulic pressure. The drive current for the solenoids of the pressure-increasing linear control valve 65A and the pressure-decreasing linear control valve 65B is controlled by the control. That is, the brake ECU 100 energizes the solenoids of the pressure-increasing linear control valve 65A and the pressure-decreasing linear control valve 65B so that the control pressure Px (= wheel cylinder pressure) detected by the control pressure sensor 104 follows the target hydraulic pressure. Control the amount (current value).

  As a result, the hydraulic fluid is supplied from the power hydraulic pressure generator 30 to each wheel cylinder 42 via the pressure-increasing linear control valve 65A and the main flow path 52, and the control pressure Px (= wheel cylinder pressure) increases to apply braking force to the wheels. Is generated. Further, the hydraulic fluid is discharged from the wheel cylinder 42 through the main flow path 52 and the pressure-reducing linear control valve 65B to the reservoir flow path 57, so that the control pressure Px (= wheel cylinder pressure) is lowered and the braking force generated on the wheels. Can be adjusted appropriately.

  For example, when the brake operation by the driver is released, the energization to the solenoids of all solenoid valves (electromagnetic on-off valves) constituting the hydraulic pressure control valve device 50 is cut off, so that all the solenoid valves (solenoids) The on-off valve is returned to the original position shown in FIG. In this way, when all the solenoid valves (electromagnetic on-off valves) are returned to their original positions, the hydraulic pressure (working fluid) of the wheel cylinder 42FR of the right front wheel is in the open state, and the master cut valve 63 and the master pressure pipe 11 are in the open state. After that, it is returned to the master cylinder 21 and the reservoir 22. The hydraulic pressure (hydraulic fluid) of the wheel cylinder 42FL of the left front wheel passes through the master cut valve 64, the communication passage 89 of the pressure increasing mechanism 80, the pilot passage 16, and the master pressure pipe 12 (master pressure pipe 12a). Returned to the cylinder 21 and the reservoir 22. The hydraulic pressure (hydraulic fluid) of the left and right rear wheel cylinders 42RR and 42RL does not flow out to the main flow path 52 by the holding valve 61R in the closed state, but passes through the pressure reducing valve 62RL and the reservoir flow path 57 in the open state. To the reservoir 22.

  It should be noted that the present invention does not necessarily require that the brake regenerative cooperative control be performed, and needless to say, can be applied to a vehicle that does not generate a regenerative braking force. In this case, the target hydraulic pressure may be directly calculated based on the brake operation amount in the linear control mode. The target hydraulic pressure is set to a larger value as the brake operation amount increases, for example, using a map or a calculation formula.

  Next, the backup mode will be described as an example. In a vehicle brake device, the brake ECU 100 performs a predetermined initial check. By this initial check, for example, a switching control failure of each electromagnetic valve (each electromagnetic on-off valve) or an abnormal operation of the brake ECU 100 itself is performed. When an abnormality is detected in the control system (electrical system) such as, or when the possibility of leakage of hydraulic fluid is detected, the brake ECU 100 operates the brake device of the vehicle in the backup mode to apply braking force to the wheels. Is generated.

  First, when an abnormality is detected in the control system (electric system), the brake ECU 100 cuts off the energization of the solenoids of all the electromagnetic valves (electromagnetic on-off valves) and returns to the original position shown in FIG. As a result, the pressure-increasing linear control valve 65A and the pressure-decreasing linear control valve 65B are closed when the solenoid is de-energized, and the power hydraulic pressure generator 30 is connected to each wheel cylinder 42 via the main flow path 52. Is cut off from. In the present embodiment, the pressure increase mechanism cut valve 90 is opened, so that the pressure increase mechanism 80 communicates with the accumulator 32. Further, the holding valve 61FR and the holding valve 61R are closed, and the holding valve 61FL is opened. For this reason, the right front wheel wheel cylinder 42FR and the left and right rear wheel wheel cylinders 42RR, 42RL are blocked from the main flow path 52, and only the left front wheel brake cylinder 42FL communicates with the main flow path 52.

  In this state, when the brake pedal 10 is depressed by the driver, the hydraulic fluid in the pressurizing chambers 21a1 and 21b1 is pressurized as the pressurizing pistons 21a and 21b of the master cylinder 21 advance. Thereby, the hydraulic pressure (master cylinder pressure Pmc_FR) of the pressurizing chamber 21a1 is supplied to the wheel cylinder 42FR of the right front wheel via the master pressure pipe 11, the master pressure flow path 53, and the master cut valve 63 in the valve open state. The brake unit 40FR can be operated satisfactorily.

  On the other hand, the hydraulic pressure (master cylinder pressure Pmc_FL) in the pressurizing chamber 21b1 is supplied to the pressure increasing mechanism 80 via the master pressure pipe 12 (12a) and the pilot passage 16, and the pressure increasing mechanism 80 starts operating. That is, in the pressure increasing mechanism 80, the stepped piston 82 moves forward, the communication through the communication path 89 between the small diameter side chamber 84 and the large diameter side chamber 83 is blocked by the valve opening member 88, and the hydraulic pressure in the small diameter side chamber 84 is Will increase. When the valve-opening member 88 moves forward and the high-pressure supply valve 86 is opened, high-pressure hydraulic fluid is supplied from the accumulator 32 into the high-pressure chamber 85 via the pressure-increasing mechanism cut valve 90 that is open. The accumulator pressure Pacc is transmitted to the small diameter side chamber 84.

  As a result, the hydraulic pressure (servo pressure) in the small-diameter side chamber 84 is made higher than the master cylinder pressure Pmc_FL, and left via the master pressure pipe 12 (12b), the master pressure flow path 54, and the master cut valve 64 in the valve open state. Supplied to the front wheel cylinder 42FL. Since the holding valve 61FL is in the open state, the hydraulic fluid supplied via the master cut valve 64 flows into the main flow path 52. In this case, since the holding valves 61FR and 61R connected to the main flow path 52 are maintained in the closed state, the hydraulic fluid flowing into the main flow path 52 fills the main flow path 52 and other wheel cylinders 42FL, 42RR and 42RL. Against spill. Accordingly, the servo pressure (hydraulic fluid) is supplied to the wheel cylinder 42FL of the left front wheel via the master cut valve 64, so that the brake unit 40FL can be operated satisfactorily.

  In this state, the pressure pump 31 of the power hydraulic pressure generating device 30 is in a stopped state, so that the hydraulic pressure of the accumulator 32 (accumulator pressure Pacc) gradually decreases. For this reason, when the accumulator pressure Pacc becomes equal to or lower than the hydraulic pressure in the high pressure chamber 85, the check valve provided in the high pressure supply passage 15 prevents the flow of hydraulic fluid from the high pressure chamber 85 to the accumulator 32. 82 is prevented from moving forward, the hydraulic pressure in the small-diameter side chamber 84 does not increase any more, and the pressure-increasing mechanism 80 cannot exhibit the boosting function. When the hydraulic pressure in the pressurizing chamber 21b1 of the master cylinder 21 (master cylinder pressure Pmc_FL) becomes higher than the hydraulic pressure in the small-diameter side chamber 84 by the pedal depression force of the driver on the brake pedal 10, the master cylinder pressure Pmc_FL is changed to the bypass passage 17, It is supplied to the wheel cylinder 42FL of the left front wheel through the master pressure pipe 12b, the master pressure channel 54 and the master cut valve 64.

  Here, since the holding valve 61R is in a closed state, the hydraulic pressure (servo pressure or master cylinder pressure Pmc_FL) of the pressurizing chamber 21b1 is supplied to the left and right rear wheel cylinders 42RR and 42RL via the main flow path 52. Not. This is because the amount of hydraulic fluid that can be supplied from one pressurizing chamber 21b1 of the master cylinder 21 is determined, and when the number of wheel cylinders 42 to be supplied increases, the hydraulic pressure of the wheel cylinder 42 is sufficiently increased. This is because it does not cause a problem that it cannot be performed. Therefore, in this embodiment, when an abnormality occurs in the control system (electric system), at least master cylinder pressures Pmc_FR and Pmc_FL are supplied to the wheel cylinders 42FR and 42FL on the left and right front wheels, and the two brake units 40FR and 40FL are supplied. Works well.

  Next, the backup mode when the possibility of liquid leakage is detected will be described. When the brake ECU 100 detects the possibility of liquid leakage to the brake device of the vehicle based on, for example, a change (decrease) in the control pressure Px detected by the control pressure sensor 104, as shown in FIG. Side holding valves 61FR and 61FL are closed, left and right rear wheel holding valves 61R are opened, and master cut valves 63 and 64 are opened. Further, the brake ECU 100 closes the simulator cut valve 72, maintains the pressure increase mechanism cut valve 90 in the closed state, and closes all the pressure reducing valves 62.

  As a result, the wheel cylinder 42RR and the wheel cylinder 42RL of the left and right rear wheels are connected to the power hydraulic pressure generator 30 via the holding valve 61R, the main passage 52, the pressure-increasing linear control valve 65A, the accumulator pressure passage 55, and the accumulator pressure pipe 13. The pressure pump 31 and / or the accumulator 32 are communicated. Therefore, in the wheel cylinders 42RR and 42RL, the accumulator pressure Pacc is controlled (regulated) by the pressure-increasing linear control valve 65A, and the hydraulic pressure is set to the control pressure Px.

  On the other hand, the wheel cylinder 42FR of the right front wheel communicates with the pressurizing chamber 21a1 of the master cylinder 21 via the master cut valve 63, the master pressure passage 53 and the master pressure pipe 11, and the hydraulic pressure is set to the master cylinder pressure Pmc_FR. The left front wheel cylinder 42FL is connected to the pressurizing chamber 21b1 of the master cylinder 21 via the master cut valve 64, the master pressure passage 54, the master pressure pipe 12b, the pressure increasing mechanism 80, the pilot passage 16 and the master pressure pipe 12a. The fluid pressure is increased to a servo pressure higher than the master cylinder pressure Pmc_FL in accordance with the operation of the pressure increasing mechanism 80.

  As described above, when the possibility of liquid leakage is detected in the brake device of the vehicle, the holding valves 61FR and 61FL for the left and right front wheels are closed (blocked). Therefore, the communication between the wheel cylinder 42FR for the left and right front wheels and the wheel cylinder 42FL via the main flow path 52 is blocked, and the wheel cylinders 42FR and 42FL for the left and right front wheels and the wheel cylinder 42RR for the left and right rear wheels via the main flow path 52 are blocked. , 42RL is disconnected. That is, when the possibility of liquid leakage is detected in the vehicle brake device, the wheel cylinders 42 of the front wheel and the rear wheel are shut off, and the three brake systems of the right front wheel, the left front wheel, and the left and right rear wheels are independent of each other. Will do. As a result, even if liquid leakage occurs in one of these three brake systems, the other brake systems are not affected.

  Specifically, in the left front wheel brake unit 40FL, for example, let us assume a case where liquid leaks from the wheel cylinder 42FL to the outside or an abnormality occurs in the sealing performance of the pressure reducing valve 62FL. In this case, in the linear control mode, the brake ECU 100 is based on, for example, the accumulator pressure Pacc detected by the accumulator pressure sensor 101 or a decrease in the control pressure Px detected by the control pressure sensor 104. Although it is possible to detect the possibility of a liquid leak, the position where the liquid leak has occurred cannot be specified. However, as described above, by making the three brake systems of the right front wheel, the left front wheel, and the left and right rear wheels independent from each other, temporarily, liquid leakage from the wheel cylinder 42FL of the left front wheel or the seal of the pressure reducing valve 62FL Even if an abnormality occurs in the engine, appropriate braking force can be generated by supplying the master cylinder pressure Pmc_FR to the other wheels, that is, the right front wheel, and the accumulator pressure Pacc is applied to the left and right rear wheels. An appropriate braking force can be generated by supplying the control pressure Px that controls (regulates).

  By the way, the brake ECU 100, for example, needs to execute a well-known anti-skid control based on the wheel speed Vx detected by the wheel speed sensor 106, or other sensor group (acceleration sensor or lateral sensor) mounted on the vehicle. In a situation where it is necessary to execute well-known vehicle stability control (vehicle behavior stability control) based on various physical quantities (such as longitudinal acceleration, lateral acceleration, and yaw rate) detected by an acceleration sensor, a yaw rate sensor, etc. The energization of the solenoids of the holding valve 61, the pressure reducing valve 62, and the linear control valve 65 can be controlled in accordance with skid control and vehicle stability control. Thereby, in the brake device of a vehicle, the wheel cylinder pressure in each wheel cylinder 42 can be independently controlled by increasing, decreasing and holding pressure. This will be specifically described below.

  As described above, the right front wheel wheel cylinder 42FR is connected to the main flow path 52 via the holding valve 61FR and the reservoir flow path via the pressure reducing valve 62FR on the left and right front wheels side of the vehicle brake device according to the present embodiment. The front left wheel cylinder 42FL is connected to the main flow path 52 via the holding valve 61FL and to the reservoir flow path 57 via the pressure reducing valve 62FL. Further, the wheel cylinder 42FR for the right front wheel is connected to the pressurizing chamber 21a1 of the master cylinder 21 via the master cut valve 63, and the wheel cylinder 42FL for the left front wheel is connected to the pressurizing chamber 21b1 of the master cylinder 21 via the master cut valve 64. Connected to. As a result, the wheel cylinder pressure in the wheel cylinder 42FR and the wheel cylinder pressure in the wheel cylinder 42FL can be reduced, increased, or held independently of each other.

  That is, when it becomes necessary to reduce only the wheel cylinder pressure in the wheel cylinder 42FR of the right front wheel according to the anti-skid control or the vehicle stability control, the brake ECU 100 cuts off the energization to the solenoid and opens the holding valve 61FR. By maintaining the valve closed state, communication between the wheel cylinder 42FR and the main flow path 52 is prohibited. Then, the brake ECU 100 opens the pressure reducing valve 62FR, for example, by energizing the solenoid by preset duty control in order to reduce the wheel cylinder pressure required according to the anti-skid control or the vehicle stability control. Thereby, the wheel cylinder pressure in the wheel cylinder 42FR of the right front wheel is appropriately reduced according to the anti-skid control and the vehicle stability control.

  When it is necessary to reduce only the wheel cylinder pressure in the wheel cylinder 42FL of the left front wheel according to the anti-skid control or the vehicle stability control, the brake ECU 100 closes the holding valve 61FL by energizing the solenoid. By maintaining the above, communication between the wheel cylinder 42FL and the main flow path 52 is prohibited. Then, the brake ECU 100 opens the pressure reducing valve 62FL by energizing the solenoid by a preset duty control in order to reduce the wheel cylinder pressure required according to the anti-skid control or the vehicle stability control. Thereby, the wheel cylinder pressure in the wheel cylinder 42FL of the left front wheel is appropriately reduced in accordance with the anti-skid control and the vehicle stability control.

  On the other hand, when it is necessary to increase only the wheel cylinder pressure in the wheel cylinder 42FR of the right front wheel in accordance with the anti-skid control or vehicle stability control (particularly vehicle stability control), the brake ECU 100 is in the linear control mode. The holding valve 61FR is maintained in the open state, the holding valve 61FL is shifted to the closed state by energizing the solenoid, the energization to the solenoid is interrupted, and the holding valve 61R is shifted to the closed state. This prohibits communication between the main flow path 52 and the wheel cylinder 42FL for the left front wheel and the wheel cylinders 42RR and 42RL for the left and right rear wheels. In the linear control mode, as described above, the pressure reducing valve 62 is maintained in a closed state. Then, the brake ECU 100 increases the control pressure Px of the main flow path 52 by the pressure-increasing linear control valve 65A in order to increase the wheel cylinder pressure required according to the anti-skid control or the vehicle stability control, and the increased control pressure Px is transmitted (supplied) to the wheel cylinder 42FR via the holding valve 61FR. Thereby, the wheel cylinder pressure in the wheel cylinder 42FR of the right front wheel is appropriately increased in accordance with the anti-skid control and the vehicle stability control.

  Further, when it is necessary to increase only the wheel cylinder pressure in the wheel cylinder 42FL of the left front wheel in accordance with the anti-skid control or vehicle stability control (particularly vehicle stability control), the brake ECU 100 is in the linear control mode. The holding valve 61FL is maintained in the open state, and the holding valve 61FR and the holding valve 61R are shifted to the closed state by cutting off the energization to the solenoid. This prohibits communication between the main flow path 52 and the wheel cylinder 42FL for the right front wheel and the wheel cylinders 42RR and 42RL for the left and right rear wheels. In the linear control mode, as described above, the pressure reducing valve 62 is maintained in a closed state. Then, the brake ECU 100 increases the control pressure Px of the main flow path 52 by the pressure-increasing linear control valve 65A in order to increase the wheel cylinder pressure required according to the anti-skid control or the vehicle stability control, and the increased control pressure Px is transmitted (supplied) to the wheel cylinder 42FL via the holding valve 61FL. Thereby, the wheel cylinder pressure in the wheel cylinder 42FL of the left front wheel is appropriately increased according to the anti-skid control and the vehicle stability control.

  It should be noted that only the wheel cylinder pressure in the right front wheel cylinder 42FR (or the left front wheel cylinder 42FL) according to the anti-skid control or vehicle stability control when the possibility of the above-described liquid leakage is detected and in the backup mode. When it is necessary to increase the pressure, for example, the brake ECU 100 shifts the master cut valve 64 on the left front wheel side (or the master cut valve 63 on the right front wheel side) to a closed state by energizing the solenoid, By energizing the solenoid, the left front wheel side pressure reducing valve 62FL (or the right front wheel side pressure reducing valve 62FR) is opened by a preset duty control. Thus, only the wheel cylinder pressure of the right front wheel wheel cylinder 42FR (or only the wheel cylinder pressure of the left front wheel wheel cylinder 42FL) can be increased (relatively increased).

  Thus, on the left and right front wheels, the wheel cylinders 42FR and 42FL are connected to the main flow path 52 via the holding valves 61FR and 61FL, respectively, so that at least one of the holding valve 61FR and the holding valve 61FL is closed. By maintaining, the wheel cylinders 42FR and 42FL can be shut off from each other. Thereby, the wheel cylinder pressure of the wheel cylinder 42FR for the right front wheel and the wheel cylinder pressure of the wheel cylinder 42FL for the left front wheel can be appropriately reduced or increased independently.

  Further, as described above, on the left and right rear wheels of the vehicle brake device according to the present embodiment, the right rear wheel wheel cylinder 42RR and the left rear wheel wheel cylinder 42RL are connected via a common holding valve 61R. Connected to the main flow path 52. Specifically, the wheel cylinder 42RR for the right rear wheel is connected to the holding valve 61R via the throttle valve MV1 provided in the individual flow path 51RR downstream of the common holding valve 61R, and via the pressure reducing valve 62RR. To the reservoir channel 57. The wheel cylinder 42RL for the left rear wheel is connected to the holding valve 61R via a throttle valve MV2 provided in the individual flow path 51RL on the downstream side of the common holding valve 61R, and is reservoired via a pressure reducing valve 62RL. Connected to the flow path 57.

  In this way, even when the left and right rear wheel cylinders 42RR and 42RL are connected to the main flow path 52 via one common holding valve 61R, the wheel cylinders 42RR and 42RL are respectively throttle valves MV1. , MV2 and the pressure reducing valves 62RR and 62RL to the reservoir flow path 57, the wheel cylinder pressure in the wheel cylinder 42RR and the wheel cylinder pressure in the wheel cylinder 42RL are independent of each other. The pressure can be reduced or increased. This will be described in detail below.

  When following anti-skid control and vehicle stability control, the left and right rear wheel side, as well as the left and right front wheel side, respectively, sets the wheel cylinder pressure in the right rear wheel wheel cylinder 42RR and the wheel cylinder pressure in the left rear wheel wheel cylinder 42RL. It is necessary to reduce the pressure independently, increase the pressure, or maintain the pressure. In this case, for example, the wheel cylinder of the right rear wheel and the wheel cylinder of the left rear wheel are connected to the main flow path via one common holding valve, and a throttle valve is provided between the holding valve and each wheel cylinder. In a vehicle brake device (hereinafter, this device is referred to as a comparison device) that is not provided with a wheel, it is difficult to independently reduce or increase the wheel cylinder pressures in the left and right rear wheel cylinders. There is a case.

  That is, in the comparison device, for example, when it is necessary to reduce only the wheel cylinder pressure in the wheel cylinder of the right rear wheel according to the anti-skid control or the vehicle stability control, the common holding valve is normally shifted to the closed state. The right rear wheel pressure reducing valve provided between the wheel cylinder of the right rear wheel and the reservoir flow path is opened. However, in the comparison device, the wheel cylinder of the right rear wheel and the wheel cylinder of the left rear wheel, which are on the downstream side of the holding valve, are always in communication with each other directly through the individual flow paths. Therefore, simply opening the pressure reducing valve on the right rear wheel side reduces the wheel cylinder pressure in the wheel cylinder on the right rear wheel, and as shown schematically in FIG. The wheel cylinder pressure in the wheel cylinder of the left rear wheel during control (during pressure holding) will be reduced. Therefore, in the comparison device, only the wheel cylinder pressure in the right rear wheel wheel cylinder (or only the wheel cylinder pressure in the left rear wheel wheel cylinder) is reduced by simple opening / closing control of the holding valve and the pressure reducing valve. Can be difficult.

  In comparison devices, for example, when it is necessary to increase only the wheel cylinder pressure in the wheel cylinder of the right rear wheel in accordance with anti-skid control or vehicle stability control (particularly vehicle stability control), linear control is usually used. In the mode, the common holding valve is maintained in an open state, and the control pressure of the main flow path is increased by the linear control valve. In this case, in the comparison device, the pressure was increased because the wheel cylinder of the right rear wheel and the wheel cylinder of the left rear wheel were in direct communication via the individual flow path downstream of the holding valve. Control pressure is supplied to both the right rear wheel cylinder and the left rear wheel cylinder. For this reason, in the state where the common holding valve is maintained in the open state, it goes without saying that the wheel cylinder pressure in the wheel cylinder of the right rear wheel is increased, and even the wheel cylinder pressure in the wheel cylinder of the left rear wheel. Will be increased. Therefore, in the comparison device, only the wheel cylinder pressure in the wheel cylinder of the right rear wheel (or only the wheel cylinder pressure in the wheel cylinder of the left rear wheel) is increased by simple opening / closing control of the holding valve and the pressure reducing valve. It can be difficult.

  On the other hand, in the vehicle brake device according to the present embodiment, the right rear wheel wheel cylinder 42RR is provided between the branch point P of the individual flow path 51RR and the branch point Q1 of the pressure-reducing individual flow path 56RR. A throttle valve that is connected to a common holding valve 61R via a throttle valve MV1, and in which the wheel cylinder 42RL of the left rear wheel is provided between the branch point P of the individual flow path 51RL and the branch point Q2 of the pressure-reducing individual flow path 56RL. It is connected to the common holding valve 61R via MV2. That is, in the vehicle brake device according to the present embodiment, throttle valves MV1 and MV2 are provided on the individual flow paths 51RR and 51RL that connect the wheel cylinder 42RR for the right rear wheel and the wheel cylinder 42RL for the left rear wheel.

  Accordingly, in the vehicle brake device according to the present embodiment, for example, when it is necessary to reduce only the wheel cylinder pressure in the wheel cylinder 42RR of the right rear wheel in accordance with the anti-skid control or the vehicle stability control, the brake ECU 100 As shown in FIG. 6, the common holding valve 61R is maintained in the open state by energizing the solenoids. In this case, the brake ECU 100 shifts the right rear wheel pressure reducing valve 62RR to the open state by energizing the solenoid, while maintaining the left rear wheel pressure reducing valve 62RL in the closed state by energizing the solenoid. .

  In the brake device for a vehicle in which the on / off state of the holding valve 61R and the pressure reducing valves 62RR and 62RL is controlled as described above, first, the wheel cylinder pressure in the wheel cylinder 42RR is changed by shifting the pressure reducing valve 62RR to the valve open state. Is depressurized. Therefore, it is possible to appropriately reduce the wheel cylinder pressure in the wheel cylinder 42RR in accordance with the request by the anti-skid control or the vehicle stability control.

  In this situation, since the common holding valve 61R is maintained in the open state, the inflow of hydraulic fluid from the main flow path 52 side to the wheel cylinders 42RR and 42RL side is permitted. Further, since the left rear wheel pressure reducing valve 62RL is maintained in the closed state, the hydraulic fluid is allowed to flow out from the wheel cylinder 42RL side to the common holding valve 61R and wheel cylinder 42RR side. For this reason, when the hydraulic pressure of the wheel cylinder 42RR is reduced, in other words, the hydraulic fluid supplied to the wheel cylinder 42RR flows out to the reservoir channel 57 via the pressure reducing valve 62RR, the hydraulic fluid is throttle valve MV1. To flow toward the wheel cylinder 42RR.

  By the way, when the pressure reducing valve 62RR is opened, the hydraulic fluid quickly flows out from the wheel cylinder 42RR of the right rear wheel into the reservoir flow path 57, so that the flow rate of the hydraulic fluid passing through the throttle valve MV1 increases. The pressure loss generated in MV1 increases. For this reason, when the pressure reducing valve 62RR is opened to reduce the wheel cylinder pressure in the wheel cylinder 42RR, it becomes difficult for the hydraulic fluid to pass through the throttle valve MV1 until a short time elapses after the valve is opened. As a result, a decrease in hydraulic pressure on the upstream side of the throttle valve MV1 is suppressed. As a result, the outflow of hydraulic fluid from the left rear wheel wheel cylinder 42RL via the throttle valve MV2 is suppressed, and as schematically shown in FIG. 7, for example, the wheel cylinder pressure in the wheel cylinder 42RL during pressure increase control is reduced. The decrease can be suppressed. Further, in this case, the common holding valve 61R is maintained in the open state, and the inflow of hydraulic fluid from the main flow path 52 is allowed. Therefore, for example, when the right rear wheel pressure reducing valve 62RR is opened, the control pressure Px in the main flow path 52 is slightly increased by the linear control valve 65, so that the hydraulic fluid flows out from the wheel cylinder 42RL, in other words. Further, it is possible to more reliably prevent the wheel cylinder pressure in the wheel cylinder 42RL from being reduced by supplying the hydraulic fluid.

  When it is necessary to reduce only the wheel cylinder pressure in the wheel cylinder 42RL of the left rear wheel according to the anti-skid control or the vehicle stability control, the brake ECU 100 maintains the common holding valve 61R in the open state. At the same time, the pressure reducing valve 62RL for the left rear wheel is shifted to the open state, and the pressure reducing valve 62RL for the right rear wheel is maintained in the closed state. As a result, only the wheel cylinder pressure in the wheel cylinder 42RL of the left rear wheel can be appropriately reduced as in the case where only the right rear wheel side is reduced.

  Further, in the vehicle brake device according to the present embodiment, it is necessary to increase only the wheel cylinder pressure in the wheel cylinder 42RR of the right rear wheel, for example, in accordance with anti-skid control or vehicle stability control (particularly vehicle stability control). When this occurs, the brake ECU 100 increases the control pressure Px in the main flow path 52 by the linear control valve 65, and maintains the common holding valve 61R in an open state by energizing the solenoids as shown in FIG. In addition, the brake ECU 100 maintains the right rear wheel pressure reducing valve 62RR in a closed state, while interrupting the energization of the solenoid to shift the left rear wheel pressure reducing valve 62RL to an open state.

  In the vehicle brake device in which the on / off state of the holding valve 61R and the pressure reducing valves 62RR and 62RL is controlled in this way, in particular, the control pressure Px in the main flow path 52 is increased according to the pressure increasing request by vehicle stability control. Then, the control pressure Px is transmitted to the downstream side of the common holding valve 61R, in other words, the inflow of hydraulic fluid from the main flow path 52 is allowed. In this situation, in the right rear wheel, since the pressure reducing valve 62RR is maintained in the closed state, there is no outflow of hydraulic fluid from the wheel cylinder 42RR to the reservoir channel 57, and the throttle valve MV1 with a small pressure loss is used. The hydraulic fluid flows toward the wheel cylinder 42RR, and a high control pressure Px is transmitted. That is, the wheel cylinder pressure of the wheel cylinder 42RR is increased.

  On the other hand, in this situation, since the pressure reducing valve 62RL is opened at the left rear wheel, the hydraulic fluid from the wheel cylinder 42RL to the reservoir channel 57 quickly flows out, and the wheel cylinder pressure of the wheel cylinder 42RL is reduced. Therefore, on the left rear wheel side, the flow rate of the hydraulic fluid that flows in through the common holding valve 61R and passes through the throttle valve MV2 is larger than the flow rate of the hydraulic fluid that passes through the throttle valve MV1, and the throttle valve MV2 The pressure loss generated at Therefore, when the pressure reducing valve 62RR connected to the wheel cylinder 42RL is opened, the hydraulic fluid is unlikely to pass through the throttle valve MV2 until a short time has elapsed since the valve was opened, that is, the throttle valve MV2. Further, the decrease in the control pressure Px on the upstream side is suppressed. Therefore, the high control pressure Px can be promptly transmitted to the wheel cylinder 42RR of the right rear wheel, and the wheel cylinder pressure of the wheel cylinder 42RR can be reliably increased.

  When it is necessary to increase only the wheel cylinder pressure in the wheel cylinder 42RL of the left rear wheel according to the anti-skid control or the vehicle stability control, the brake ECU 100 maintains the common holding valve 61R in the open state. At the same time, the pressure reducing valve 62RL for the left rear wheel is kept closed, and the pressure reducing valve 62RR for the right rear wheel is shifted to the open state. As a result, only the wheel cylinder pressure in the wheel cylinder 42RL of the left rear wheel can be appropriately increased as in the case of increasing the pressure only on the right rear wheel side described above.

  As can be understood from the above description, according to the present embodiment, the brake device of the vehicle supplies the liquid from the main flow path 52 on the upstream side to the wheel cylinders 42RR and the wheel cylinders 42RL on the left and right rear wheels on the downstream side. One common holding valve 61R that allows or prohibits the transmission of pressure, and pressure reducing valves 62RR and 62RL that allow or prohibit the transmission of hydraulic pressure from each of the left and right rear wheel wheel cylinders 42RR and 42RL to the reservoir 22 are provided. be able to. Further, according to the present embodiment, the vehicle brake device is provided in the individual flow path 51RR and the individual flow path 51RL that are branched at the branch point P downstream of the holding valve 61R, and the individual flow path 51RR. The throttle valve MV1 provided upstream of the branch point Q1 where the individual pressure reducing flow path 56RR branches from and the upstream side of the branch point Q2 where the individual pressure reducing flow path 56RL branches from the individual flow path 51RL. Throttle valve MV2 to be provided.

  Thereby, by providing the common holding valve 61R to which the plurality of wheel cylinders 42RR and 42RL are connected, the number of expensive holding valves 61 can be reduced, and the manufacturing cost of the brake device of the vehicle is effectively reduced. be able to. Thus, even when the number of expensive holding valves 61 is reduced, the wheel cylinder pressures in the wheel cylinder 42RR and the wheel cylinder 42RL on the left and right rear wheels can be appropriately controlled.

  That is, in the left and right rear wheels, when it is necessary to reduce the pressure of one of the wheel cylinder 42RR and the wheel cylinder 42RL independently of the other, the brake ECU 100 maintains the common holding valve 61R in the open state. The pressure reducing valve 62RR or the pressure reducing valve 62RL connected to the wheel cylinder 42RR or the wheel cylinder 42RL on the side for reducing the wheel cylinder pressure is opened, and the pressure reducing valve connected to the other wheel cylinder 42RL or the wheel cylinder 42RR. The 62RL or the pressure reducing valve 62RR can be closed. As a result, the pressure loss generated in the throttle valve MV1 or the throttle valve MV2 connected to the wheel cylinder 42RR or the wheel cylinder 42RL on the side where the wheel cylinder pressure is reduced increases, so the wheel cylinder on the side where the wheel cylinder pressure is not reduced. It can suppress effectively that the wheel cylinder pressure in 42RL or wheel cylinder 42RR falls. Therefore, even in the wheel cylinder 42RR and the wheel cylinder 42RL connected to one common holding valve 61, the wheel cylinder pressure can be reduced independently.

  Further, in the left and right rear wheels, when it is necessary to increase the pressure of one of the wheel cylinder 42RR and the wheel cylinder 42RL independently of the other, the brake ECU 100 opens the common holding valve 61R. The pressure reducing valve 62RR or the pressure reducing valve 62RL connected to the wheel cylinder 42RR or the wheel cylinder 42RL on the side to maintain and increase the wheel cylinder pressure is closed, and connected to the wheel cylinder 42RL or the wheel cylinder 42RR on the other side. The pressure reducing valve 62RL or the pressure reducing valve 62RR can be opened. As a result, the pressure loss generated in the throttle valve MV2 or the throttle valve MV1 connected to the wheel cylinder 42RL on the side where pressure is not increased or the throttle valve MV1 is increased, so that the wheel cylinder 42RR on the side where the wheel cylinder pressure is increased or A high control pressure Px (upstream hydraulic pressure) can be supplied from the main flow path 52 to the wheel cylinder 42RL, and the wheel cylinder pressure can be reliably and quickly increased. Therefore, even in the wheel cylinder 42RR and the wheel cylinder 42RL connected to one common holding valve 61, the wheel cylinder pressure can be independently increased.

  In carrying out the present invention, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the object of the present invention.

  For example, in the above embodiment, the throttle valves MV1 and MV2 are provided as throttles in the individual flow paths 51RR and 51RL on the left and right rear wheel sides. In this case, for example, the throttle valves MV1 and MV2 may be omitted as in the above-described comparison device. In this case, as described above, in the comparison device, for example, when only the right rear wheel side is depressurized, the tendency to depressurize the left rear wheel side also becomes significant, but the common holding valve is kept open. By supplying the control pressure, the influence of the pressure reduction on the right rear wheel side can be reduced, and the pressure reduction tendency on the left rear wheel side can be suppressed.

  Further, in the comparison device, for example, when only the right rear wheel side is increased, as described above, the left rear wheel side is also increased, but by opening the pressure reducing valve on the left rear wheel side, Unintentional pressure increase on the rear wheel side can be prevented. In this case, there is a tendency that the pressure on the right rear wheel side is also reduced along with the pressure reduction on the left rear wheel side, but the common holding valve is maintained in the open state and the control pressure is increased and supplied. As a result, it is possible to reduce the influence of pressure reduction on the left rear wheel side and reliably increase the pressure on the right rear wheel side. Therefore, also in the comparison device, the manufacturing cost can be reduced and the wheel cylinder pressure of each wheel cylinder can be controlled as in the above embodiment.

  In the above embodiment, the wheel cylinder 42RR and the wheel cylinder 42RL provided on the left and right rear wheels are connected to the main flow path 52 via the holding valve 61R which is one common electromagnetic on-off valve. A throttle valve MV1 and a throttle valve MV2 connected to the wheel cylinder 42RR and the wheel cylinder 42RL, respectively, were provided on the downstream side of 61R. In this case, if the brake device of the vehicle is configured such that one common electromagnetic on-off valve is connected to the two wheel cylinders on the downstream side and the main flow path on the upstream side, the wheel cylinder is The wheel position provided is not limited.

  In this case, for example, the wheel cylinder 42FR for the right front wheel and the wheel cylinder 42RL for the left rear wheel, which are in a diagonal position relationship between the front, rear, left and right in the vehicle, are connected to the main flow path 52 via one common holding valve. In addition, a throttle valve connected to the wheel cylinder 42FR and a throttle valve connected to the wheel cylinder 42RL may be provided. Alternatively, the wheel cylinder 42FL of the left front wheel and the wheel cylinder 42RR of the right rear wheel, which are in a diagonal position relationship between the front, rear, left and right in the vehicle, are connected to the main flow path 52 via one common holding valve, and the wheel It is also possible to provide a throttle valve connected to the cylinder 42FL and a throttle valve connected to the wheel cylinder 42RR. Even in these cases, as in the case of the above embodiment, only one of the wheel cylinder 42FR and the wheel cylinder 42RL can be decompressed or increased independently, and only one of the wheel cylinder 42FL and the wheel cylinder 42RR can be obtained. Can be independently reduced or increased in pressure, and the same effect as in the above embodiment can be obtained. Furthermore, by connecting the wheel cylinders in the diagonal position relationship between the front, rear, left and right in the vehicle by a common holding valve, for example, the wheel cylinders connected to each other generate braking force on the wheels, thereby Unnecessary yaw (yaw rate) can also be prevented from occurring.

  In the above embodiment, the two wheel cylinders 42RR, 42RL on the left and right rear wheel sides are connected to the main flow path 52 via one common holding valve 61R. That is, in the above embodiment, the vehicle brake device is applied to a vehicle having two rear wheels. In this case, since the common holding valve 61R can communicate or block two or more wheel cylinders and the upstream main flow path, the number of wheels on the rear wheel side is two or more, such as a truck. It goes without saying that the above-described vehicle brake device can also be applied to this vehicle. Even in this case, the same effect as the above embodiment can be obtained.

  In the above embodiment, the servo pressure output from the pressure increasing mechanism 80 is directly transmitted to the wheel cylinder 42FL. In this case, the servo pressure can be transmitted from the pressure increasing mechanism 80 to the master cylinder 21. In this case, specifically, a hydro booster is provided in the master cylinder 21 and servo pressure is supplied from the pressure increasing mechanism 80 to the hydro booster. As a result, a hydraulic pressure equivalent to the servo pressure can be transmitted to the wheel cylinder 42FL, for example, via the master cylinder 21, and the same effect as in the above embodiment can be expected.

  Moreover, in the said embodiment, the brake device of the vehicle provided with the pressure increase linear control valve 65A and the pressure reduction linear control valve 65B as the linear control valve 65 was employ | adopted and implemented. In this case, the pressure-reducing linear control valve 65B may be omitted, and a vehicle brake device including only the pressure-increasing linear control valve 65A may be employed. Moreover, in the said embodiment, it implemented by employ | adopting the brake device of the vehicle provided with the pressure increase mechanism 80 and the pressure increase mechanism cut valve 90. FIG. In this case, it is also possible to employ a vehicle brake device that does not include the pressure increase mechanism 80 and the pressure increase mechanism cut valve 90. Even in these cases, the same effects as in the above embodiment can be obtained.

  Furthermore, in the above-described embodiment, when the above-described initial check is performed, there is a possibility that an operating sound accompanying the switching operation of each electromagnetic on-off valve is generated. Therefore, for example, when the vehicle is HV or PHV, an initial check is performed when the rotational speed of the internal combustion engine is equal to or higher than a predetermined rotational speed, or when the vehicle is EV, the volume of the audio device The initial check can be executed when is at a predetermined volume or higher. As a result, the operating sound generated by the initial check can be mixed into the sound emitted from the internal combustion engine or the sound emitted from the audio device, and the operating sound can be hardly perceived by the occupant. .

  DESCRIPTION OF SYMBOLS 10 ... Brake pedal, 20 ... Master cylinder unit, 30 ... Power hydraulic pressure generator, 40 ... Brake unit, 50 ... Hydraulic pressure control valve apparatus, 51 ... Individual flow path, 52 ... Main flow path, 56 ... Individual flow path for pressure reduction , 61FR, 61FL, 61R ... holding valve, 62FR, 62FL, 62RR, 62RL ... pressure reducing valve, 65 ... linear control valve, 100 ... brake ECU, MV1, MV2 ... throttle valve (throttle)

Claims (10)

Comprising a master cylinder that generates hydraulic pressure in response to the operation of a brake pedal by a driver, a powered hydraulic pressure source that generates hydraulic pressure by driving a pressurizing pump, and a plurality of electromagnetic valves controlled by electrical signals, A valve mechanism to which a hydraulic pressure output from the master cylinder or the power hydraulic pressure source is transmitted, and a wheel to which the hydraulic pressure output from the master cylinder or the power hydraulic pressure source is transmitted via the valve mechanism In a vehicle brake device comprising: a wheel cylinder that applies a braking force to the control unit; and a control unit that controls the operation of the valve mechanism.
The valve mechanism is
At least the plurality of hydraulic pressures output from the power hydraulic pressure source provided at the upstream side of a branch point where the hydraulic fluid flowing from the power hydraulic pressure source branches to the plurality of wheel cylinders. A holding valve that is an electromagnetic on-off valve that allows or prohibits transmission of the motor to the wheel cylinder;
A vehicle comprising: a pressure reducing valve that is provided for each of the plurality of wheel cylinders and is an electromagnetic on-off valve that allows or prohibits transmission of hydraulic pressure from each of the wheel cylinders to a reservoir. Brake device. The vehicle brake device according to claim 1,
The valve mechanism further comprises:
A brake device for a vehicle, comprising a throttle provided between the branch point and each of the plurality of wheel cylinders. The vehicle brake device according to claim 2,
The aperture is
A brake device for a vehicle, which is provided between the branch point and a branch point branched to the pressure reducing valve downstream of the branch point and upstream of the wheel cylinder. In the brake device of the vehicle according to any one of claims 1 to 3,
The control means includes
When reducing the hydraulic pressure in a part of the plurality of wheel cylinders,
A brake device for a vehicle, wherein the pressure reducing valves provided in some of the wheel cylinders are controlled to be opened and the holding valve is controlled to be opened. In the brake device of the vehicle according to any one of claims 1 to 3,
The control means includes
When increasing the hydraulic pressure in some of the plurality of wheel cylinders,
Controlling the pressure reducing valve provided in the part of the wheel cylinders to a closed state and controlling the holding valve to be opened,
Furthermore, the brake device for a vehicle is characterized in that the pressure reducing valve provided in another wheel cylinder of the plurality of wheel cylinders is controlled to be opened. In the vehicle brake device according to any one of claims 1 to 5,
The plurality of wheel cylinders are:
A braking device for a vehicle, which applies braking force to wheels on the left and right rear wheels of the vehicle. The vehicle brake device according to claim 6,
The plurality of wheel cylinders are:
A braking device for a vehicle, which applies braking force to two wheels on the left and right rear wheels of the vehicle. In the vehicle brake device according to any one of claims 1 to 5,
The plurality of wheel cylinders are:
A braking device for a vehicle, which applies braking force to wheels in a diagonal position relationship between front, rear, left and right in the vehicle. The vehicle brake device according to any one of claims 1 to 8,
A booster connected to the master cylinder and the power hydraulic pressure source to generate a hydraulic pressure having a predetermined ratio with respect to the hydraulic pressure from the master cylinder using the hydraulic pressure from the power hydraulic pressure source. A vehicle brake device comprising a mechanism. The vehicle brake device according to claim 9, wherein
The pressure increasing mechanism is
A brake device for a vehicle, which is mechanically operated by a hydraulic pressure output from the master cylinder in accordance with an operation of the brake pedal by the driver.

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