JP5471528B2 - Brake system - Google Patents

Description

  The present invention relates to inspection of a control system in a brake system.

In Patent Document 1, (a) a hydraulic brake that suppresses rotation of a wheel, (b) a master cylinder, (c) an accumulator, and (d) a drive of an electric actuator using the hydraulic pressure of the accumulator A pressure-increasing mechanism that is actuated by the brake, and (e) a selection valve that selects a higher one of the hydraulic pressure of the pressure-increasing mechanism and the hydraulic pressure of the master cylinder and supplies the selected pressure to the brake cylinder of the hydraulic brake The system is described.
When the electric actuator is normal, the pressure increasing device is operated by the electric actuator, and when it is abnormal, the pressure increasing device is operated by the hydraulic pressure of the master cylinder. Further, when a high-pressure hydraulic fluid can be supplied from the accumulator, a hydraulic pressure higher than the hydraulic pressure of the master cylinder can be generated. However, when the accumulator hydraulic pressure decreases, the output hydraulic pressure of the pressure increasing mechanism also decreases. Become.
In Patent Document 2, (a) a hydraulic brake that is provided on the front, rear, left, and right wheels of the vehicle and suppresses the rotation of the wheel; A brake system is described that includes a mechanical booster provided between a cylinder and (d) an electromagnetic valve provided between a pump device and a brake cylinder. In this brake system, when the difference between the detected value of the brake cylinder hydraulic pressure sensor and the target hydraulic pressure is large, the solenoid valve or the like is abnormal. When the solenoid valve or the like is normal, the hydraulic pressure of the pump device controlled by the solenoid valve is supplied to the front and rear brake cylinders. When the solenoid valve or the like is abnormal, the hydraulic pressure generated by the mechanical pressure increasing mechanism is supplied to the front wheel brake cylinder, and the hydraulic pressure of the master cylinder is supplied to the rear wheel brake cylinder.

Special table 2009-502645 Japanese Patent Laid-Open No. 10-287227

  The subject of this invention is improving the reliability of the test | inspection of a control system in a hydraulic brake system.

Means and effects for solving the problem

A brake system according to a first aspect of the present invention includes: (a) a hydraulic brake provided on each of a plurality of wheels of a vehicle and operated by hydraulic pressure of a brake cylinder to suppress rotation of the wheels; and (b) electric energy. A power hydraulic pressure source that generates hydraulic pressure by supplying the hydraulic pressure, and (c) a common passage to which the hydraulic hydraulic pressure source is connected and to which the brake cylinders of the plurality of hydraulic brakes are connected, and (d) An output hydraulic pressure control valve provided in a control pressure passage connecting the common passage and the power hydraulic pressure source, and controlling the output hydraulic pressure of the power hydraulic pressure source to supply the common passage; ) A hydraulic pressure source hydraulic pressure sensor for detecting hydraulic pressure on the power hydraulic pressure source side of the output hydraulic pressure control valve; and (f) control for detecting hydraulic pressure on the common passage side of the output hydraulic pressure control valve. A pressure sensor; and (g) a connection between the common passage and the control pressure passage, and the control pressure sensor. A communication blocking device that is provided between the plurality of brake cylinders and allows the connection portion and the control pressure sensor and the plurality of brake cylinders to communicate with each other, and (h) the communication blocking device to The plurality of brake cylinders are controlled by controlling the hydraulic pressure in the common passage by controlling at least the output hydraulic pressure control valve in a state where the connecting portion and the control pressure sensor are in communication with each other. A brake hydraulic pressure control device for controlling the hydraulic pressure of the hydraulic pressure source, and (i) in a state where the connection portion and the control pressure sensor are disconnected from the plurality of brake cylinders by the communication cutoff device. When the detected value is larger than the first set pressure, the output hydraulic pressure control valve is switched from the closed state to the open state, and then the detected value of the control pressure sensor is When increased to more than the abnormality judgment threshold value determined by the first setting pressure, the control system of the braking system is intended to include a first control system inspection unit which is normal.
A plurality of brake cylinders and a power hydraulic pressure source are connected to the common passage. An output hydraulic pressure control valve is provided in the control pressure passage connecting the power hydraulic pressure source and the common passage, and the hydraulic pressure of the power hydraulic pressure source is controlled by the output hydraulic pressure control valve and supplied to the common passage. The In a state where the common passage and the brake cylinder are communicated, the hydraulic pressure in the common passage is supplied to the brake cylinder, and the hydraulic pressure from the power hydraulic pressure source controlled by the output hydraulic pressure control valve is supplied. The
Also, when the control system is normal and the hydraulic pressure on the power hydraulic pressure source side of the output hydraulic pressure control valve is higher than the hydraulic pressure on the common passage side, the output hydraulic pressure control valve can be switched from the closed state to the open state. For example, the hydraulic pressure on the power hydraulic pressure side and the hydraulic pressure on the common passage side should be almost the same. Therefore, if the detection value of the hydraulic pressure source hydraulic pressure sensor and the detection value of the control pressure sensor are compared after the output hydraulic pressure control valve is switched to the open state, the control system is inspected for normality. It can be performed.
In this case, a plurality of brake cylinders, that is, elements that consume a large amount of hydraulic fluid are all blocked from the common passage. Further, the elastic deformation amount of the common passage and the compression amount of the hydraulic fluid are small. Therefore, if the output hydraulic pressure control valve is switched from the closed state to the open state, the hydraulic pressure in the common passage should increase quickly and reliably. Therefore, when the output hydraulic pressure control valve is switched from the closed state to the open state, the detection value of the hydraulic pressure source hydraulic pressure sensor is compared with the detection value of the control pressure sensor, so that the control can be performed accurately and quickly. The system inspection can be performed, and the reliability of the control system inspection can be improved.
The control pressure sensor is provided on the common passage side from the output hydraulic pressure control valve, and may be provided in the control pressure passage or in the common passage.
The communication cutoff device includes a plurality of electromagnetic open / close valves, and includes, for example, an electromagnetic open / close valve (for example, an individual control valve) provided between the brake cylinder and the common passage. It may include an electromagnetic on-off valve provided (for example, a front / rear shut-off valve, a left / right shut-off valve). If the front and rear shut-off valves and the left and right shut-off valves are closed, it is possible to shut off two or more brake cylinders from the connecting portion or the like.
Patent Document 1 does not describe the inspection of the control system.
In the inspection of the control system described in Patent Document 2, the detection value of the sensor provided on the upstream side of the electromagnetic valve is not compared with the detection value of the sensor provided on the downstream side. This is different from the control system inspection in the brake system.

Patentable invention

  In the following, the invention that is claimed to be claimable in the present application (hereinafter referred to as “claimable invention”. The claimable invention is at least the “present invention” to the invention described in the claims. Some aspects of the present invention, including subordinate concept inventions of the present invention, superordinate concepts of the present invention, or inventions of different concepts) will be illustrated and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is merely for the purpose of facilitating understanding of the claimable invention, and is not intended to limit the set of components constituting the claimable invention to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

(1) a hydraulic brake provided on each of a plurality of wheels of the vehicle and operated by the hydraulic pressure of a brake cylinder to suppress rotation of the wheels;
A powered hydraulic pressure source that generates hydraulic pressure by supplying electrical energy;
A common passage to which the hydraulic fluid pressure source is connected and to which the brake cylinders of the plurality of hydraulic brakes are connected;
An output hydraulic pressure control valve provided in a control pressure passage connecting the common passage and the power hydraulic pressure source, and controlling an output hydraulic pressure of the power hydraulic pressure source to supply the common passage;
A hydraulic pressure source hydraulic pressure sensor for detecting hydraulic pressure on the power hydraulic pressure source side of the output hydraulic pressure control valve;
A control pressure sensor for detecting a fluid pressure on the common passage side of the output fluid pressure control valve;
A connection portion of the common passage with the control pressure passage, the control pressure sensor, and the plurality of brake cylinders, and the connection portion, the control pressure sensor, and the plurality of brake cylinders communicate with each other. A communication blocking device for blocking,
In a state where the connection portion and the control pressure sensor and the plurality of brake cylinders are in communication with each other by the communication cutoff device, the hydraulic pressure in the common passage is controlled by controlling at least the output hydraulic pressure control valve. A brake system including a brake fluid pressure control device that controls fluid pressure of the plurality of brake cylinders,
The hydraulic pressure source hydraulic pressure sensor after the output hydraulic pressure control valve is switched from a closed state to an opened state in a state where the connection portion and the control pressure sensor are disconnected from the plurality of brake cylinders by the communication cutoff device A brake comprising a control system inspection device that compares a detected value of the control system with a detected value of the control pressure sensor and performs a control system inspection to determine whether or not the control system of the brake system is normal. system.
The output hydraulic pressure control valve may be a normally closed electromagnetic on / off valve that is closed when no current is supplied to the solenoid, or a normally open electromagnetic on / off valve that is open when no current is supplied. Good. In addition, even with a linear control valve that can continuously control the differential pressure (and / or) opening degree of the front and rear by continuous control of the amount of current supplied to the solenoid, the supply current to the solenoid can be turned ON / OFF. It may be a simple on-off valve that can be switched between an open state and a closed state. Hereinafter, unless otherwise specified, in this specification, the electromagnetic on-off valve may be either a linear control valve or a simple on-off valve.
The power hydraulic pressure source is operated by supplying electric energy, and may include, for example, a pump device. If an accumulator is included, a high-pressure working fluid can be quickly supplied to the common passage. When the power hydraulic pressure source includes an accumulator, an accumulator pressure sensor that detects the hydraulic pressure of the hydraulic fluid stored in the accumulator is often provided, so the accumulator pressure sensor is used as the hydraulic pressure source hydraulic pressure sensor. can do.
(2) When the detected value of the hydraulic pressure source hydraulic pressure sensor is larger than the first set pressure, the control system inspection device switches the output hydraulic pressure control valve from the closed state to the open state, and then the control The brake according to (1), further including a first control system inspection unit that determines that the control system is normal when a detection value of the pressure sensor is equal to or greater than an abnormality determination threshold value determined by the first set pressure. system.
In the closed state of the output hydraulic pressure control valve, the detected value of the hydraulic pressure source hydraulic pressure sensor is higher than the first set pressure, and the detected value of the control pressure sensor is equal to or lower than the first set pressure. For example, in a non-operating state of the hydraulic brake, the detection value of the control pressure sensor (for example, the hydraulic pressure in the common passage) is almost atmospheric pressure.
In this state, a plurality of brake cylinders are shut off from the common passage, the output hydraulic pressure control valve is switched from the closed state to the open state, and the detected value of the control pressure sensor is determined to be abnormal, which is determined by the first set pressure. If it exceeds the value, the control system is considered normal.
The abnormality determination threshold value can be substantially the same as the first set pressure, or can be a value slightly smaller than the first set pressure.
In addition, when the first set pressure is small, the abnormality determination threshold value is also decreased, and when the first set pressure is large, the abnormality determination threshold value is also increased. When the abnormality determination threshold is a small value, the inspection range in the control pressure sensor is narrowed. However, when the abnormality determination threshold is a large value, the inspection range can be widened. Further, the reliability of inspection can be improved.
If the first set pressure is a value in the vicinity of the upper limit value of the hydraulic pressure range used in the control of the brake cylinder hydraulic pressure (control upper limit value), the control pressure sensor is inspected in the range used in the control of the brake cylinder. It can be performed.
If the value of the first set pressure (sensor upper limit value) is set so that the abnormality determination threshold is determined to be a value near the upper limit value of the pressure detectable range of the control pressure sensor, the control pressure sensor The inspection can be performed in a pressure detectable range.
Note that if the first set pressure is the larger of the upper limit value for control and the upper limit value for sensor, the reliability of the inspection of the control pressure sensor can be further enhanced.
(3) The output hydraulic pressure control valve is a linear control valve capable of controlling the differential pressure before and after the output hydraulic pressure control valve to a smaller value when the supply current to the solenoid is small.
As the supply current to the solenoid increases, the control system inspection device decreases the differential pressure before and after the value obtained by subtracting the detection value of the control pressure sensor from the detection value of the hydraulic pressure source hydraulic pressure sensor. In this case, the brake system according to (1) or (2), further including a second control system inspection unit that the control system is normal.
For example, in the output hydraulic pressure control valve, an electromagnetic driving force Fd corresponding to the amount of current supplied to the solenoid and a differential pressure acting force Fp corresponding to the differential pressure before and after act in a direction to separate the valve element from the valve seat. In the case where the biasing force Fs of the spring acts in the direction in which the valve element is seated on the valve seat (Fp + Fd: Fs), when no current is supplied to the solenoid, in principle, the valve is closed. When a current is supplied to the solenoid and the sum of the differential pressure acting force Fp and the electromagnetic driving force Fd becomes larger than the spring biasing force Fs (Fp + Fd> Fs), the state is switched to the open state. FIG. 3 (b) shows the relationship between the differential pressure and the current supplied to the solenoid (opening characteristics of the output hydraulic pressure control valve) when the output hydraulic pressure control valve is switched from the closed state to the open state. In this case, since it can be considered that the spring biasing force Fs is substantially constant, the electromagnetic driving force Fd required to switch the output hydraulic pressure control valve to the open state may be smaller as the differential pressure is larger. I understand. Further, from this characteristic, it can be seen that, in the output hydraulic pressure control valve, if the amount of current supplied to the solenoid is gradually increased, the differential pressure before and after is gradually decreased.
Based on the characteristics of the output hydraulic pressure control valve, when the amount of current supplied to the solenoid is gradually increased, the differential pressure before and after (the difference between the detected value of the hydraulic pressure source hydraulic pressure sensor and the detected value of the control pressure sensor) If it decreases gradually, it can be assumed that the control system is normal.
When the hydraulic pressure of the power hydraulic pressure source can be considered to be substantially constant during the control system inspection, the fact that the differential pressure becomes small means that the liquid pressure on the common passage side of the output hydraulic pressure control valve is reduced. The pressure is increased. Therefore, it can be assumed that the control system is normal when the detected value of the control pressure sensor increases as the supply current amount increases.
(4) The brake system includes (a) a manual hydraulic pressure source that generates hydraulic pressure by a driver's brake operation, and (b) the manual hydraulic pressure using the hydraulic pressure of the power hydraulic pressure source. Including a pressure increasing mechanism capable of increasing the hydraulic pressure of the source and outputting it,
The pressure increasing mechanism is connected to the common passage,
The communication blocking device includes a pressure-increasing mechanism communication blocking unit for communicating or blocking the connection unit and the control pressure sensor and the pressure-increasing mechanism; and
A third control system test in which the control system test device performs the control system test in a state where the plurality of brake cylinders and the pressure increasing mechanism are shut off from the connection portion and the control pressure sensor by the communication cutoff device; The brake system according to any one of (1) to (3), including a section.
The pressure-increasing mechanism communication shut-off section includes a plurality of electromagnetic on-off valves provided corresponding to the pressure-increasing mechanism (for example, a pressure-increasing mechanism shut-off valve provided between the pressure increasing mechanism and the common passage). It is good also as an electromagnetic on-off valve provided in order to connect / cut off the brake cylinder of this. For example, when the front-rear shut-off valve provided in the common passage (the brake cylinder can be shut off from the connecting portion, etc.) is closed, and the pressure increasing mechanism can be shut off from the connecting portion, etc. The front / rear shut-off valve can be a pressure-increasing mechanism communication shut-off portion. The front / rear shut-off valve is considered to have both a function of shutting off the brake cylinder and a function of shutting off the pressure increasing mechanism.
For example, when the control system inspection is performed in a non-operating state of the brake operating member, the pressure increasing mechanism is operated by the hydraulic pressure of the manual hydraulic pressure source. When the pressure increasing mechanism is connected to the common passage in the control system inspection, the hydraulic pressure in the common passage is transferred to the manual hydraulic pressure source via the pressure increasing mechanism. There is a risk of spillage. In that case, it is desirable that the pressure-increasing mechanism is shut off from the common passage when the control system is inspected.
(5) One or more of the plurality of brake cylinders are connected to the common passage via individual passages, the pressure increasing mechanism is connected via a servo pressure passage, and the communication cut-off is performed. The device includes (a) an upstream individual control valve provided in each of the individual passages, (b) a pressure increase mechanism communication cutoff valve provided in the servo pressure passage, and (c) the upstream individual control valve. And a valve control unit that switches the pressure-increasing mechanism cutoff valve to an open state and a closed state, respectively,
The third control system inspection unit performs the control system inspection in a state where all the upstream individual control valves and the pressure-increasing mechanism communication cutoff valve are closed. Brake system.
In the brake system described in this section, communication is performed by individual control valves (upstream individual control valves) provided in the individual passages, pressure increase mechanism cutoff valves provided between the pressure increase mechanism and the common passage, and the like. A shut-off device is configured.
The upstream individual control valve can also be used when controlling the hydraulic pressure of each brake cylinder. The upstream individual control valves provided corresponding to one or more of the plurality of brake cylinders are opened and closed in common in the control system inspection, but are individually opened and closed in the control of the brake cylinder hydraulic pressure.
The same applies to the pressure-increasing mechanism shut-off valve, which can be opened and closed in common with all upstream individual control valves in the control system inspection, but is opened and closed separately from the upstream individual control valve in controlling the brake cylinder hydraulic pressure. Be made.
When the plurality of brake cylinders are individually connected to the common passage, the upstream side individual control valve is provided corresponding to each of the plurality of brake cylinders. On the other hand, when the brake cylinders for the left and right rear wheels are provided in the common passage via one individual passage, one upstream side individual control valve is provided corresponding to the brake cylinder for the left and right rear wheels. In this case, the hydraulic pressures of the left and right rear brake cylinders are controlled in common.
(6) The control system inspection device includes a fourth control system inspection unit that performs the control system inspection in a state where the low pressure source and the plurality of brake cylinders are in communication with each other. The brake system as described in any one of these.
When the control system inspection is performed in a non-actuated state of the hydraulic brake, the hydraulic pressure in the common passage may be caused to flow out through the communication cutoff device for some reason, which may cause the hydraulic brake to be activated. There is.
On the other hand, if the control system inspection is performed in a state where the brake cylinder is connected to the low pressure source, even if the hydraulic pressure in the common passage is caused to flow out through the communication cutoff device, the hydraulic brake The operation can be prevented, and dragging can be prevented.
The low-pressure source can be a reservoir that stores the hydraulic fluid at atmospheric pressure, or a manual-type hydraulic pressure source when the brake operation member is not operated.
(7) The brake system includes: (a) a low pressure source; and (b) a downstream individual control valve provided between the low pressure source and one or more of the plurality of brake cylinders. ,
In the fourth control system inspecting unit, all the downstream individual control valves are opened, and the plurality of brake cylinders are disconnected from the connection unit and the control pressure sensor by the communication cutoff device. The brake system according to (6), including a low-pressure source communication inspection unit that performs the control system inspection.
When the low pressure source is a reservoir, the downstream side individual control valve can be a pressure reducing valve (individual control valve) used for controlling the brake cylinder hydraulic pressure.
(8) The brake system includes: (a) a manual hydraulic pressure source that generates hydraulic pressure by operating a brake operating member; and (b) a reservoir that stores hydraulic fluid. A master-reservoir communication inspection unit that performs the control system inspection in a state where the brake cylinders of the left and right front wheels of the vehicle are connected to the manual hydraulic pressure source and the brake cylinders of the left and right rear wheels are connected to the reservoir. The brake system according to (6) or (7).
Even if the brake operation member is operated during the control system inspection when the brake cylinder of the left and right front wheels is connected to the manual hydraulic pressure source and the control system inspection is performed in a state where the brake cylinder is disconnected from the reservoir, The hydraulic brakes on the left and right front wheels can be actuated.
If the hydraulic pressure is generated in the manual hydraulic pressure source and the hydraulic pressure is supplied to the brake cylinders on the left and right front wheels, it does not affect the connection and the part including the control pressure sensor. It is also possible to continue the inspection.
(9) The control system inspection apparatus includes a fifth control system inspection unit that performs the control system inspection when a predetermined control system inspection condition is satisfied, and any one of items (1) to (8) Brake system described in 1.
(10) The brake system according to (9), wherein the control system inspection condition includes at least one of the fact that the hydraulic brake is in an inoperative state and the traveling speed of the vehicle is equal to or higher than a set speed.
The control system inspection is performed when a predetermined control system inspection condition is satisfied.
Since a plurality of brake cylinders are cut off from the connecting portion or the like, the hydraulic pressure of the power hydraulic pressure source cannot be supplied to the brake cylinder. Therefore, it is desirable that the control system inspection is performed in a non-operating state of the hydraulic brake.
Further, it is desirable that the operation sound generated in the inspection of the control system is performed in a state where it can be confused with other sounds. When the traveling speed of the vehicle is equal to or higher than the set speed, the sound generated in the driving device is often larger than the operating sound generated in the inspection.
In the brake system described in Patent Document 2, the inspection is performed in the operation state of the hydraulic brake, and Patent Document 2 does not describe that the inspection is performed in the non-operation state of the hydraulic brake.
(11) The brake system according to any one of (9) or (10), wherein the control system inspection condition includes no request for operation of the hydraulic brake.
For example, when the brake operation member is not operated, the case where there is no request | requirement of operating an automatic brake corresponds.
(12) The control system inspection condition includes at least one of a case where a brake operation member provided in a vehicle is not operated and a possibility that the brake operation member is operated is low (9) The brake system according to any one of items 1 to (11).
In the period when the so-called initial check is performed, the possibility that the automatic brake is operated is low. Therefore, if it is detected whether or not the brake operation member is operated, it can be determined whether or not there is a hydraulic brake activation request.
Further, it is desirable that the control system inspection be performed when there is no hydraulic brake operation request. Therefore, it is reasonable that the inspection is performed when the possibility that the brake operation member is operated is low. For example, it is rare that the brake operation member is operated again within a set time after the operation of the brake operation member is released. Therefore, it can be performed within a set time after the operation of the brake operation member is released.
(13) The brake system according to any one of (9) to (12), wherein the control system inspection condition includes that a volume of the audio device is equal to or higher than a set volume.
This is particularly effective when the brake system is applied to a hybrid vehicle or an electric vehicle.
(14) The brake system according to any one of (9) to (13), wherein the control system inspection condition includes that an engine speed of a vehicle drive device is a set number or more.
This is particularly effective when applied to an internal combustion drive vehicle.
(15) The control system inspection device includes a brake operation inspection stop unit that stops the control system inspection when an operation of a brake operation member provided in the vehicle is performed during the control system inspection. The brake system according to any one of items (1) to (14).
When the brake operation member is operated, the hydraulic pressure in the common passage is controlled by the control of the output hydraulic pressure control valve using the hydraulic pressure of the power hydraulic pressure source, and the controlled hydraulic pressure is braked. In the brake system in which the hydraulic brake is operated by being supplied to the cylinder, it is desirable that the inspection of the control system is canceled when the brake operation member is operated.
In contrast, when the brake system is provided with a manual hydraulic pressure source that generates hydraulic pressure by operating the brake operating member, the manual hydraulic pressure source and at least one of the plurality of brake cylinders communicate with each other. Thus, when the control system is inspected, the inspection can be continued even if the brake operation member is operated during the inspection. In this case, the control pressure of the output hydraulic pressure control valve cannot be supplied to the brake cylinder, but the hydraulic pressure of the manual hydraulic pressure source can be supplied.
(16) When the detection value of the control pressure sensor is lower than the detection value of the hydraulic pressure source hydraulic pressure sensor, the control system inspection device includes at least the output hydraulic pressure control valve and the control pressure sensor. The brake system according to any one of items (1) to (15), including a control system abnormality detection unit that detects that one of them is abnormal.
If the detected value of the control pressure sensor does not increase even though the output hydraulic pressure control valve is switched from the closed state to the open state, the output hydraulic pressure control valve is not open. Such as fluid leakage in a common passage, communication disconnection device abnormality, fluid pressure source fluid pressure sensor abnormality, and the like. In this case, if the output hydraulic pressure control valve, the control pressure sensor, and the communication cutoff device are inspected separately by another control system inspection device, and whether or not there is a liquid leak is checked separately, Can be specified.
If the above-described separate inspections show that some of the above-described components are normal, it can be assumed that the other components are abnormal. For example, when it is known that the communication cutoff device is normal and that there is no liquid leakage in the common passage, one or more of a control pressure sensor, an output hydraulic pressure control valve, and a hydraulic pressure source hydraulic pressure sensor It can be considered abnormal.
It is also possible to estimate that a component that hardly causes an abnormality is normal and a component that easily causes an abnormality is abnormal.
(17) The pressure increasing mechanism is provided between the common passage, the power hydraulic pressure source, and the manual hydraulic pressure source, and is mechanically operated by the hydraulic pressure of the manual hydraulic pressure source. The brake system according to any one of items (4) to (16).
In the brake system described in this section, the pressure increasing mechanism is provided separately from the power hydraulic pressure source and is mechanically operated. Therefore, a hydraulic pressure higher than the hydraulic pressure of the manual hydraulic pressure source can be generated even when the electric system is abnormal.
(18) The pressure-increasing mechanism includes: (a) a mechanical pressure booster that boosts and outputs the hydraulic pressure of the manual hydraulic pressure source; and (b) a mechanical pressure booster and the power hydraulic pressure source. The brake according to (17), further comprising: a high-pressure check valve that is provided in between, and that allows a flow of hydraulic fluid from the power hydraulic pressure source to the mechanical pressure intensifier and prevents a reverse flow. system.

1 is a diagram illustrating an entire vehicle on which a hydraulic brake system according to an embodiment of the present invention is mounted. It is a brake circuit diagram of the hydraulic brake system. It is sectional drawing of the pressure increase linear control valve and pressure reduction linear control valve contained in the said hydraulic brake system. It is a flowchart showing the initial check program memorize | stored in the memory | storage part of brake ECU contained in the said hydraulic brake system. It is a figure which shows the state of the change of the detected value of an accumulator pressure sensor in case the said initial check is performed, and the detected value of a brake cylinder pressure sensor. It is a flowchart showing the brake fluid pressure control program memorize | stored in the memory | storage part of the said brake ECU. It is a figure which shows a state when the brake hydraulic pressure control program is performed in the said hydraulic brake system (when normal). It is a figure which shows another state when a brake fluid pressure control program is performed in the said hydraulic brake system (when a control system is abnormal). It is a figure which shows another state when the brake hydraulic pressure control program is performed in the said hydraulic brake system (when there exists a possibility of a fluid leak). It is a figure which shows the state in case the test | inspection of a control system is performed in the said hydraulic brake system. It is a flowchart showing another initial check program memorize | stored in the memory | storage part of the said brake ECU.

Hereinafter, a brake system according to an embodiment of the present invention will be described in detail with reference to the drawings.
First, a vehicle equipped with a hydraulic brake system that is a brake system according to an embodiment of the present invention will be described.
This vehicle is a hybrid vehicle including an electric motor and an engine as drive devices. In the hybrid vehicle, the left and right front wheels 2 and 4 as drive wheels are driven by a drive device 10 including an electric drive device 6 and an internal combustion drive device 8. The driving force of the driving device 10 is transmitted to the left and right front wheels 2 and 4 via the drive shafts 12 and 14. The internal combustion drive 8 includes an engine 16, an engine ECU 18 that controls the operating state of the engine 16, and the like. The electrical drive 6 includes an electric motor 20, a power storage device 22, a motor generator 24, a power conversion device 26, A motor ECU 28, a power split mechanism 30 and the like are included. When the electric motor 20, the motor generator 24, and the engine 16 are connected to the power split mechanism 30, and only the driving torque of the electric motor 20 is transmitted to the output member 32 by these controls, the driving torque of the engine 16 and the electric power When both the driving torque of the motor 20 is transmitted, the output is switched to when the output of the engine 16 is output to the motor generator 24 and the output member 32, or the like. The driving force transmitted to the output member 32 is transmitted to the drive shafts 12 and 14 via a speed reducer and a differential device.
The power conversion device 26 includes an inverter and the like, and is controlled by the motor ECU 28. By the current control of the inverter, at least a rotational drive state in which electric energy is supplied to the electric motor 20 from the power storage device 22 and rotated, and charging that charges the power storage device 22 by functioning as a power generator by regenerative braking Switch to state. In the charged state, regenerative braking torque is applied to the left and right front wheels 2 and 4. In that sense, the electric drive device 6 can be considered as a regenerative brake device.

The hydraulic brake system includes a brake cylinder 42 of the hydraulic brake 40 provided on the left and right front wheels 2, 4, a brake cylinder 52 of the hydraulic brake 50 provided on the left and right rear wheels 46 and 48 (see FIG. 2), and these A hydraulic pressure control unit 54 that can control the hydraulic pressure of the brake cylinders 42 and 52 is included. The hydraulic pressure control unit 54 is controlled by a brake ECU 56 mainly including a computer.
The vehicle is provided with a hybrid ECU 58, and the hybrid ECU 58, the brake ECU 56, the engine ECU 18, and the motor ECU 28 are connected via a CAN (Car area Network) 59. These can communicate with each other, and necessary information is communicated as appropriate.

In addition, this hydraulic brake system can also be mounted not only on a hybrid wheel but on a plug-in hybrid vehicle, an electric vehicle, and a fuel cell vehicle. In the electric vehicle, the internal combustion drive device 8 is not necessary. In a fuel electromagnetic vehicle, a driving motor is driven by a fuel cell stack or the like.
The present hydraulic brake system can also be mounted on an internal combustion drive vehicle. In a vehicle in which the electric drive device 6 is not provided, regenerative braking torque is not applied to the drive wheels 2, 4, so regenerative cooperative control is not performed.

  Hereinafter, the hydraulic brake system will be described, but when it is necessary to distinguish the brake cylinder, the hydraulic brake, and various electromagnetic on-off valves, which will be described later, according to the positions of the front, rear, left and right wheels, It is described with reference numerals (FL, FR, RL, RR) to be represented, and representatively or when it is not necessary to distinguish, it is described without reference numerals.

The hydraulic brake system according to the first embodiment includes a brake circuit shown in FIG.
Reference numeral 60 denotes a brake pedal as a brake operation member, and reference numeral 62 denotes a master cylinder as a manual hydraulic pressure source that generates hydraulic pressure by operating the brake pedal 60. A power hydraulic pressure source 64 includes a pump device 65 and an accumulator 66. The hydraulic brakes 40 and 50 are actuated by the hydraulic pressure of the brake cylinders 42 and 52 to suppress the rotation of the wheels. In the present embodiment, the hydraulic brakes 40 and 50 are disc brakes.
The hydraulic brakes 40 and 50 can be drum brakes. Alternatively, the hydraulic brake 40 for the front wheels 2 and 4 can be a disc brake, and the hydraulic brake 50 for the rear wheels 46 and 48 can be a drum brake.
The master cylinder 62 is of a tandem type having two pressure pistons 68 and 69, and the pressure chambers 70 and 72 are in front of the pressure pistons 68 and 69, respectively. In this embodiment, the pressurizing chambers 70 and 72 correspond to manual hydraulic pressure sources, respectively. The pressurizing chambers 72 and 70 are respectively connected to the brake cylinder 42FL of the hydraulic brake 40FL of the left front wheel 2 and the brake cylinder of the hydraulic brake 40FR of the right front wheel 4 via master passages 74 and 76 as manual passages. 42FR is connected.
The pressurizing chambers 70 and 72 are communicated with the reservoir 78 when the pressurizing pistons 68 and 69 reach the retracted end, respectively. The interior of the reservoir 78 is partitioned into a plurality of storage chambers 80, 82, and 84 that store hydraulic fluid. The storage chambers 80 and 82 are provided corresponding to the pressurization chambers 70 and 72, respectively, and the storage chamber 74 is provided corresponding to the pump device 65.

  In the motive power hydraulic pressure source 64, the pump device 65 includes a pump 90 and a pump motor 92, and the hydraulic fluid is pumped up from the storage chamber 84 of the reservoir 78 by the pump 90, and is stored in the accumulator 66. The pump motor 92 is controlled so that the pressure of the hydraulic fluid stored in the accumulator 66 is within a predetermined setting range. Further, the relief valve 94 prevents the discharge pressure of the pump 90 from becoming excessive.

A pressure increasing mechanism 100 as a high pressure generator is provided between the power hydraulic pressure source 64 and the master passage 76. The pressure-increasing mechanism 100 includes a housing 102 and a stepped piston 104 that is liquid-tight and slidably fitted to the housing 102. A small-diameter side chamber 112 is provided on the side.
A high pressure chamber 114 connected to the power hydraulic pressure source 64 is communicated with the small diameter side chamber 112, and a high pressure supply valve 116 is provided between the small diameter side chamber 112 and the high pressure chamber 114. The high pressure supply valve 116 includes a valve element 120, a valve seat 122, and a spring 124, and the urging force of the spring 124 acts in a direction to press the valve element 120 against the valve seat 122. The high pressure supply valve 116 is a normally closed valve.
In the small diameter side chamber 112, a valve opening member 125 is provided so as to face the valve element 120, and a spring 126 is provided between the valve opening member 125 and the stepped piston 104. The biasing force of the spring 126 acts in a direction to separate the valve opening member 125 from the stepped piston 104.
A spring 128 (return spring) is provided between the step portion of the stepped piston 104 and the housing 102 to urge the stepped piston 104 in the backward direction. A stopper (not shown) is provided between the stepped piston 104 and the housing 102 to restrict the forward end position of the stepped piston 104.
Further, the stepped piston 104 is formed with a communication passage 130 that allows the large-diameter side chamber 110 and the small-diameter side chamber 112 to communicate with each other. The communication passage 130 allows the large-diameter side chamber 110 and the small-diameter side chamber 112 to communicate with each other while being separated from the valve opening member 125 at least at the retracted end position of the stepped piston 104. If it contacts the valve member 125, it will interrupt | block.
In this embodiment, the mechanical pressure intensifier 134 is constituted by the housing 102, the stepped piston 104, the high pressure supply valve 116, the valve opening member 125, and the like.

The high pressure chamber 114 and the power hydraulic pressure source 64 are connected by a high pressure supply passage 131, and the flow of hydraulic fluid from the power hydraulic pressure source 64 to the high pressure chamber 114 is allowed in the high pressure supply passage 131, and the flow is in the opposite direction. A high-pressure check valve 132 is provided to prevent this. The high pressure side check valve 132 allows the flow of hydraulic fluid from the power hydraulic pressure source 64 to the high pressure chamber 114 when the hydraulic pressure of the power hydraulic pressure source 64 is higher than the hydraulic pressure of the high pressure chamber 114. When the hydraulic pressure of the motive power hydraulic pressure source 64 is equal to or lower than the hydraulic pressure of the high pressure chamber 114, the power supply pressure source 64 is in a closed state and prevents bidirectional flow. Therefore, even if liquid leakage occurs in the power hydraulic pressure source 64, the backflow of the hydraulic fluid from the high pressure chamber 114 to the power hydraulic pressure source 64 is prevented, and the decrease in the hydraulic pressure in the small diameter side chamber 112 is prevented.
Further, a bypass passage 136 is provided between the master passage 74 and the output side of the mechanical pressure intensifier 134 (which may be the small-diameter side chamber 112) to bypass and connect the mechanical pressure intensifier 134. A manual check valve 138 is provided that allows the flow of hydraulic fluid from the master passage 74 to the output side of the mechanical pressure intensifier 134 and prevents reverse flow.

In the pressure increasing mechanism 100, when the hydraulic pressure in the pressurizing chamber 72 of the master cylinder 14 is supplied to the large-diameter side chamber 110, the hydraulic fluid is supplied to the small-diameter side chamber 112 through the communication path 130.
When the force in the forward direction acting on the stepped piston 104 (due to the hydraulic pressure in the large-diameter side chamber 110) becomes larger than the urging force of the return spring 128, the piston is moved forward. When the stepped piston 104 contacts the valve opening member 125 and the liquid passage 130 is blocked, the liquid pressure in the small-diameter side chamber 112 increases and is output (supplied to the common passage as will be described later).
Further, when the high pressure supply valve 116 is switched to the open state by the advancement of the valve opening member 125, high pressure hydraulic fluid is supplied from the high pressure chamber 114 to the small diameter side chamber 112, and the hydraulic pressure in the small diameter side chamber 112 increases. On the other hand, when the pressure of the hydraulic fluid stored in the accumulator 66 is higher than the pressure in the high pressure chamber 114, the hydraulic pressure in the accumulator 66 is supplied to the high pressure chamber 114 through the high pressure check valve 132 and supplied to the small diameter side chamber 112. Is done.
In the stepped piston 104, the hydraulic pressure in the large-diameter side chamber 110 includes a force acting on the large-diameter side (fluid pressure of the master cylinder 62 x pressure-receiving area) and a force acting on the small-diameter side (output hydraulic pressure x pressure-receiving area). It is adjusted to a balanced size and output. In this sense, the pressure increasing mechanism 100 can be referred to as a booster mechanism.
Further, the manual check valve 138 prevents the output hydraulic pressure of the mechanical pressure intensifier 134 from flowing toward the master passage 74.
On the other hand, when the hydraulic pressure in the accumulator 66 is equal to or lower than the hydraulic pressure in the high pressure chamber 114, the high-pressure check valve 132 prevents the flow of bidirectional hydraulic fluid between the accumulator 66 and the high pressure chamber 114. Therefore, the stepped piston 104 cannot advance any further. Further, the stepped piston 104 may not be able to advance by contacting the stopper. From this state, when the hydraulic pressure in the pressurizing chamber 72 becomes higher than the hydraulic pressure in the small-diameter side chamber 112, the hydraulic pressure is supplied to the output side of the mechanical pressure intensifier 134 through the pressure intensifier bypass passage 136 and the manual check valve 138. Is done.

On the other hand, the brake cylinders 42FL, FR of the left and right front wheels 2, 4 and the brake cylinders 52RL, RR of the left and right rear wheels 46, 48 are connected to the common passage 152 via individual passages 150FL, FR, RL, RR, respectively.
The individual passages 150FL, FR, RL, RR are provided with holding valves (SHij: i = F, R, j = L, R) 153FL, FR, RL, RR, and brake cylinders 42FL, 42FR, 52RL, respectively. , 52RR and the reservoir 78 are provided with pressure reducing valves (SRij: i = F, R, j = L, R) 156FL, FR, RL, RR, respectively.
In the present embodiment, the holding valves 153FL and RR provided corresponding to the left front wheel 2 and the right rear wheel 48 are normally open electromagnetic on-off valves that are open when no current is supplied to the solenoid. The holding valves 153FR and RL provided corresponding to the front wheel 4 and the left rear wheel 46 are normally closed electromagnetic on-off valves that are closed when no current is supplied to the solenoid.
As a result, one of the holding valves 153FL and FR corresponding to the left and right wheels 2 and 4 on the front wheel side and the holding valves 153RL and RR corresponding to the left and right wheels 46 and 48 on the rear wheel side is a normally open electromagnetic on-off valve. Is a normally closed solenoid valve.
In addition, the holding valves 153FL and RR corresponding to one of the two wheels in the diagonal position, that is, the left front wheel 2 and the right rear wheel 48 are normally open electromagnetic on-off valves, and the other two wheels in the diagonal position. The holding valves 153FR and RL corresponding to the wheels, that is, the right front wheel 4 and the left rear wheel 46 are normally closed electromagnetic on-off valves.
The pressure reducing valves 156FL, FR, RR are normally closed electromagnetic open / close valves, and the pressure reducing valve 156RL provided corresponding to the left rear wheel 46 is a normally open electromagnetic open / close valve.

In addition to the brake cylinders 42 and 52, a power hydraulic pressure source 64 and a pressure increasing mechanism 100 are also connected to the common passage 152.
The power hydraulic pressure source 64 is connected to the connection portion 171 of the common passage 152 via the control pressure passage 170. A pressure increasing linear control valve (SLA) 172 is provided in the control pressure passage 170, and a pressure reducing linear control valve (SLR) 176 is provided between the control pressure passage 170 and the reservoir 78. The output hydraulic pressure of the power hydraulic pressure source 64 is controlled by the control of the pressure increasing linear control valve 172 and the pressure reducing linear control valve 176 and supplied to the common passage 152. The pressure increase linear control valve 172 and the pressure reduction linear control valve 176 constitute an output hydraulic pressure control valve device 178. Further, the pressure-increasing linear control valve 172 and the pressure-decreasing linear control valve 176 can be referred to as output hydraulic pressure control valves. Both the pressure-increasing linear control valve 172 and the pressure-decreasing linear control valve 176 are normally closed electromagnetic on-off valves that are in a closed state when no current is supplied to the solenoid, and continuously control the magnitude of the current supplied to the solenoid. Thus, the magnitude of the output hydraulic pressure can be continuously controlled.

  As shown in FIG. 3A, each of the pressure increasing linear control valve 172 and the pressure reducing linear control valve 176 includes a seating valve including a valve element 180 and a valve seat 182, a spring 184, and a solenoid 186. The biasing force Fs of the spring 184 acts in a direction that causes the valve element 180 to approach the valve seat 182, and current is supplied to the solenoid 186 so that the driving force Fd causes the valve element 180 to separate from the valve seat 182. Works. Further, in the pressure-increasing linear control valve 172, a differential pressure acting force Fp corresponding to the pressure difference between the power hydraulic pressure source 64 and the common passage 152 acts in a direction to separate the valve element 180 from the valve seat 182. In the control valve 176, a differential pressure acting force Fp corresponding to the differential pressure between the common passage 152 (control pressure passage 170) and the reservoir passage 78 acts (Fp + Fd: Fs). In any case, by controlling the supply current to the solenoid 186, the differential pressure acting force F3 is controlled, and the hydraulic pressure in the control pressure passage 170 is controlled. It can also be considered that the hydraulic pressure in the common passage 152 is controlled by the control of the pressure-increasing linear control valve 172 and the pressure-decreasing linear control valve 176.

FIG. 3B shows the characteristic of the pressure-increasing linear control valve 172, which is the relationship between the valve opening pressure (differential pressure) and the supply current. When the sum of the differential pressure acting force Fp and the driving force Fd of the solenoid 186 becomes larger than the urging force Fs of the spring 184, the pressure-increasing linear control valve 172 is switched to the open state. It can be seen that it is necessary to supply the current.
In addition, in the pressure-increasing linear control valve 172, a force corresponding to a differential pressure between the hydraulic pressure of the power hydraulic pressure source 64 and the hydraulic pressure of the common passage 152 acts as a differential pressure acting force, but the hydraulic pressure of the accumulator 66 is It can be considered almost constant. For this reason, the differential pressure can be considered to be smaller when the hydraulic pressure in the common passage 152 is larger than when the hydraulic pressure is small, and there is a demand to increase the hydraulic pressure in the common passage 152 (brake cylinders 42 and 52). In the case where there is a request to do so, the supply current to the solenoid 186 needs to be increased.
In other words, if the current supplied to the solenoid 186 is increased, the differential pressure across the front and rear can be reduced, and the hydraulic pressure in the common passage 152 is increased.

A table showing the characteristics shown in FIG. 3B is stored in advance in the storage unit of the brake ECU 56. In the control of the supply current of the pressure-increasing linear control valve 172, the differential pressure is acquired, and the amount of supply current necessary for switching the pressure-increasing linear control valve 172 from the closed state to the open state from the differential pressure and the above-described characteristic table I (valve opening current) is acquired, and furthermore, a necessary increase in supply current is acquired based on the target value of hydraulic pressure in the common passage 152 (target value of brake cylinder hydraulic pressure), and the amount of supply current is calculated based on these Is determined.
The same applies to the pressure-reducing linear control valve 176, and the hydraulic pressure in the reservoir 78 can be regarded as substantially constant, so that the differential pressure before and after can be the hydraulic pressure in the common passage 152.

The pressure increasing mechanism 100 is connected to the common passage 152 via a servo pressure passage 190. The servo pressure passage 190 is provided with a pressure increase mechanism cutoff valve (SREG) 192 as a high pressure generator cutoff valve. The pressure-increasing mechanism cutoff valve 192 is a normally open electromagnetic on-off valve.
On the other hand, the master passages 74 and 76 are connected to the downstream side of the holding valves 153FL and FR of the individual passages 150FL and FR of the left and right front wheels 2 and 4, respectively. (SMCFL, FR) 194FL, FR are provided. The master cutoff valve 194FL is a normally closed electromagnetic on-off valve, and the master cutoff valve 194FR is a normally open electromagnetic on-off valve.
Further, the stroke simulator 200 is connected to the master passage 74 via a simulator control valve 202. The simulator control valve 202 is a normally closed electromagnetic on-off valve.

As described above, in this embodiment, the hydraulic pressure control is performed by the power type hydraulic pressure source 64, the output hydraulic pressure control valve device 178, the master cutoff valve 194, the holding valve 153, the pressure reducing valve 156, the pressure increasing mechanism cutoff valve 192, and the like. Part 54 is configured.
The hydraulic pressure control unit 54 is controlled based on a command from the brake ECU 56. As shown in FIG. 1, the brake ECU 56 mainly includes a computer including an execution unit, an input / output unit, a storage unit, and the like. The input / output unit includes a brake switch 218, a stroke sensor 220, a master cylinder pressure sensor. 222, accumulator pressure sensor 224, brake cylinder pressure sensor 226, level warning 228, wheel speed sensor 230, door open / close switch 232, ignition switch 234, accelerator switch 236, etc., and hydraulic pressure control unit 54, etc. are connected. .
The brake switch 218 is a switch that turns from OFF to ON when the brake pedal 60 is operated.
The stroke sensor 220 detects an operation stroke (STK) of the brake pedal 60. In this embodiment, two sensors are provided, and similarly, an operation stroke of the brake pedal 60 is detected.
The master cylinder pressure sensor 222 detects the hydraulic pressure (PMCFL, FR) in the pressurizing chamber of the master cylinder 62, and is provided in the master passages 74 and 76, respectively. In principle, the hydraulic pressures in the master passages 74 and 76 are the same.
As described above, in this embodiment, the stroke sensor 220 and the master cylinder pressure sensor 222 are divided into two systems, and even if one of the two sensors breaks down, the brake operation state can be detected by the other. It becomes.

The accumulator pressure sensor 224 detects the hydraulic pressure (PACC) of the working fluid stored in the accumulator 66. The pressure increasing linear control valve 172 is provided on the power hydraulic pressure source 64 side and corresponds to a hydraulic pressure source hydraulic pressure sensor.
The brake cylinder pressure sensor 226 detects the hydraulic pressure (PWC) of the brake cylinders 42 and 52 and is provided in the common passage 152. When the holding valve 153 is in the open state, the brake cylinders 42 and 52 and the common passage 152 are communicated with each other, so that the hydraulic pressure in the common passage 152 can be set to the hydraulic pressure in the brake cylinders 42 and 52. Further, since the hydraulic pressure in the common passage 152 is controlled by the output hydraulic pressure control valve device 178 including the pressure-increasing linear control valve 172, it can be set as the control pressure of the output hydraulic pressure control valve device 178. Furthermore, the brake cylinder pressure sensor 226 is located on the common passage side of the pressure-increasing linear control valve 172, and corresponds to the control pressure sensor.
The differential pressure before and after used in the control of the pressure-increasing linear control valve 172 is acquired as the difference between the detection value of the accumulator pressure sensor 224 and the detection value of the brake cylinder pressure sensor 226 and is used in the control of the pressure-reduction linear control valve 176. Is obtained as a detection value of the brake cylinder pressure sensor 226.
The level warning 228 is a switch that is turned on when the hydraulic fluid stored in the reservoir 78 falls below a predetermined set amount. In the present embodiment, when the amount of the hydraulic fluid stored in any one of the three storage chambers 80, 82, 84 becomes equal to or less than the set amount, it is turned ON.
Wheel speed sensors 230 are provided corresponding to the left and right front wheels 2, 4 and the left and right rear wheels 46, 48, respectively, and detect the rotational speed of the wheels. Further, the traveling speed of the vehicle is acquired based on the rotational speed of the four wheels.
The door opening / closing switch 232 detects opening / closing of a door provided in the vehicle. It may be one that detects opening / closing of the door on the driver's seat side, or one that detects opening / closing of other doors. For example, a door courtesy lamp switch can be used as a door opening / closing switch.
The ignition switch (IGSW) 234 is a main switch of the vehicle, and the accelerator switch 236 is a switch that is turned on when an accelerator operating member (not shown) is in an operating state.
The CAN 59 is connected to an inter-vehicle control ECU 240, a collision avoidance ECU 242, an audio ECU 244, and the like, and controls the hydraulic pressure control unit 54 and the like in response to a braking request from the inter-vehicle control ECU 240 and the collision avoidance ECU 242. In addition, information indicating the operating state of the audio device (for example, information indicating volume) is supplied from the audio ECU 244.
Furthermore, various programs, tables, and the like are stored in the storage unit.

<Initial check>
The initial check program represented by the flowchart of FIG. 4 is executed at predetermined time intervals.
In the initial check, many items are inspected, and the control system inspection will be described.
The control system inspection is performed when a predetermined control system inspection condition is satisfied. The control system inspection condition is a condition that the brake switch 218 is OFF and the traveling speed of the vehicle is equal to or higher than the set speed. The speed becomes higher (speed at which the occupant does not care). When the control system inspection is not performed after the ignition switch 234 is switched from OFF to ON, the control system inspection is performed when the control system inspection condition is satisfied.
The control system includes a pressure increasing linear control valve 172, an accumulator pressure sensor 224, a brake cylinder pressure sensor 226, and the like. Since the accumulator pressure sensor 224 and the brake cylinder pressure sensor 226 are used in the control of the pressure increasing linear control valve 172, it can be considered that these are included in the control system.

In the control system inspection, all the holding valves 153 and the pressure-increasing mechanism cutoff valves 192 are in a state where the pressure-increasing linear control valve 172 is in the closed state and the hydraulic pressure of the hydraulic fluid stored in the accumulator 66 is larger than the first set pressure PACC0. Is closed, and the pressure-increasing linear control valve 172 is switched to the open state. When the detected value of the brake cylinder pressure sensor 226 reaches the abnormality determination threshold value Pth determined by the first set pressure PACC0, it is determined that the control system is normal.
The hydraulic pressure of the hydraulic fluid stored in the accumulator 66 is maintained within a predetermined set range by the control of the pump motor 92, but the first set pressure PACC0 is a value slightly smaller than the upper limit value of the set range. Is done.
The abnormality determination threshold value Pth is set to a value in the vicinity of the first set pressure PACC0, and whether or not the brake cylinder pressure sensor 226 is normal is checked within a range equal to or less than the abnormality determination threshold value Pth. become.
As shown in FIG. 5 (a), when the first set pressure (accumulator pressure) is set to a low value, an inspection in a range Ra surrounded by a broken line of the brake cylinder pressure sensor 226 is performed. When the detection value of the brake cylinder pressure sensor 226 changes as indicated by a broken line, it cannot be detected as abnormal. On the other hand, if the first set pressure is set to a high value, it is possible to inspect whether or not the detected value is normal in the range Rb surrounded by the one-dot chain line of the brake cylinder pressure sensor 226.
Further, since the first set pressure PACC0 is a value near the upper limit value of the hydraulic pressure used in the control, the brake cylinder pressure sensor 226 can be inspected in the range used in the control.

In the control system inspection, the holding valve 153 is closed and the pressure-increasing mechanism shut-off valve 192 is closed, so that the common passage 152 (the connection portion with the control pressure passage 170 and the brake cylinder pressure sensor 226) is all The brake cylinders 42 and 52 are shut off and the pressure increasing mechanism 100 is shut off. Further, the compression amount of the hydraulic fluid and the elastic deformation amount of the common passage 152 are small. Therefore, it is considered that when the pressure-increasing linear control valve 172 is switched to the open state, the fluid pressure in the common passage 152 is quickly increased to almost the same level as the accumulator pressure.
Therefore, the detected value of the brake cylinder pressure sensor 226 is determined to be abnormal until the preset set time (pressure increase waiting time) elapses after the pressure increase linear control valve 172 is switched from the closed state to the open state. When the threshold is reached, it is determined that the control system is normal.
On the other hand, if the detected value of the brake cylinder pressure sensor 226 does not reach the abnormality determination threshold value within the set time, an abnormality in the control system (abnormality of the pressure increasing linear control valve 172 being stuck, the brake cylinder pressure sensor 226). Or one or more of the abnormalities of the accumulator pressure sensor 226).

This program is executed when the control system is not inspected after the ignition switch 234 is switched from OFF to ON.
In step 1 (hereinafter abbreviated as S1. The same applies to other steps), it is determined whether or not a predetermined control system inspection condition is satisfied.
If the control system inspection condition is satisfied, it is determined in S2 and 3 whether the pressure increase waiting flag and the pressure decrease waiting flag are ON. As will be described later, the pressure increase wait flag and the pressure decrease wait flag are turned on while waiting for the pressure increase wait time and the pressure decrease wait time to elapse, and when S2 and 3 are executed first. Is OFF.

In S4, it is determined whether or not the detected value PACC by the accumulator pressure sensor 224 is larger than the first set pressure PACC0. When the accumulator pressure PACC is equal to or lower than the first set pressure PACC0, the pump motor 92 is operated in S5. Since the pressure increasing linear control valve 172 is in the closed state, the hydraulic fluid discharged from the pump 90 is not supplied to the common passage 152.
By the operation of the pump device 65, the hydraulic fluid is stored in the accumulator 66 in a pressurized state. Thereafter, S1 to S5 are repeatedly executed and increased until the actual accumulator pressure PACC becomes higher than the first set pressure PACC0.
When the pump motor 92 is started when the door opening / closing switch 232 is turned on before the ignition switch 234 is switched from OFF to ON, when S4 is executed first In addition, the accumulator pressure may already be greater than the first set pressure PACC0. In that case, S5 is not executed and the determination in S4 is YES.

If the detected value of the accumulator pressure sensor 224 is larger than the first set pressure PACC0, the pump motor 92 is stopped in S6, and the pressure reducing valves 156RL of the left and right rear wheels 46, 48 are displayed in S7 as shown in FIG. , RR, master cutoff valves 194FL, FR are opened, all holding valves 153FL, FR, RL, RR are closed, and the pressure increase mechanism cutoff valve 192 is closed.
All the brake cylinders 42FL, FR, 52RL, RR are shut off from the common passage 152 and the pressure increasing mechanism 100 is shut off. The brake cylinders 52RL and RR of the left and right rear wheels 46 and 48 are communicated with the reservoir 78, and the brake cylinders 42FL and FR of the left and right front wheels 2 and 4 are communicated with the master cylinder 62. In this embodiment, all the brake cylinders 42FL, FR, RL, RR are shut off from the common passage 152, so that the connecting portion 171 and the brake cylinder pressure sensor 226 are connected to all the brake cylinders 42FL, FR, RL, RR. Will be blocked.
Then, in S8, the current is supplied to the solenoid of the pressure-increasing linear control valve 172, thereby switching to the open state. In this embodiment, a current that is large enough to maintain the open state is maintained until the differential pressure before and after the pressure-increasing linear control valve 172 becomes substantially 0 (the pressure in the accumulator 66 and the pressure in the common passage 152 are the same). Supplied. Thereby, the common passage 152 and the accumulator 66 are communicated.

In S9, it is determined whether or not the pressure increasing waiting time has elapsed since the pressure increasing linear control valve 172 was switched to the open state. When S9 is executed for the first time, the pressure increase waiting time has not elapsed, so in S10, the hydraulic pressure (detected value of the brake cylinder hydraulic pressure sensor 226) Pwc in the common passage 152 is the abnormality determination threshold value Pth. It is determined whether or not it is larger. When S10 is first executed, it is considered that the detection value Pwc of the brake cylinder pressure sensor 226 is lower than the abnormality determination threshold value Pth. Therefore, in S11, the pressure increase waiting flag is turned ON.
The pressure increase waiting time is a time required until the hydraulic pressure Pwc in the common passage 152 becomes substantially the same as the hydraulic pressure PACC in the accumulator 66. As described above, since the hydraulic pressure in the common passage 152 is considered to increase rapidly, the pressure increase waiting time is considered to be short.

Thereafter, S1, 2, 9, 10, and 11 are repeatedly executed until the pressure increase waiting time elapses or until the detection value Pwc of the brake cylinder pressure sensor 226 reaches the abnormality determination threshold value Pth.
If the detected value Pwc of the brake cylinder pressure sensor 224 becomes equal to or higher than the abnormality determination threshold value Pth, the determination in S10 is YES and the control system is normal in S12.
On the other hand, if the detected value Pwc of the brake cylinder pressure sensor 226 does not reach the abnormality determination threshold value Pth before the pressure increase waiting time elapses, the determination in S9 is YES, and in S13, the control is performed. The system is determined to be abnormal.
In any case, after that, in S14, the pressure increase waiting flag is turned OFF, and the control system inspection end processing is performed.

In S15, holding valves 153FL, FR, RL, and RR are opened, and in S16, it is determined whether or not the depressurization waiting time has elapsed. Since the pressure reducing valves 156RL and RR and the master shut-off valves 194FL and FR are in the open state, the hydraulic pressure in the common passage 152 flows out to the reservoir 78 (the reservoir 78 through the master cylinder 62). The pressure reduction waiting time is the time required for the hydraulic pressure in the common passage 152 to flow out to the reservoir 78 and return to almost atmospheric pressure.
Before the depressurization waiting time elapses, the determination in S16 is NO, and in S17, the depressurization waiting flag is turned ON. Thereafter, S1, 2, 3, 16, and 17 are repeatedly executed, and the depressurization waiting time elapses.
When the depressurization waiting time has elapsed, the determination in S16 is YES, the depressurization waiting flag is turned off in S18, and in S19, the currents to the solenoids of all the valves are turned off and returned to their original positions.

  On the other hand, if the brake pedal 60 is operated during the control system inspection, the determination in S1 is YES and the inspection is stopped. In this case, the holding valve 153, the pressure increase mechanism cutoff valve 192, the master cutoff valve 194, and the like are controlled by a separate program such as a brake fluid pressure control program.

As described above, in this embodiment, the accumulator pressure is larger than the first set pressure PACC0, and the brake cylinders 42FL, FR, 52RL, RR and the pressure increasing mechanism 100 are disconnected from the common passage 152, and the pressure increasing linear control is performed. Valve 172 is switched to the open state. When the control system is normal, the fluid pressure in the common passage 152 quickly exceeds the abnormality determination threshold value Pth.
Therefore, if the detection value of the brake cylinder pressure sensor 226 does not reach the abnormality determination threshold value within the pressure increase waiting time, it can be seen that the control system is not normal, and the control system can be inspected promptly and Can be detected accurately, and the reliability of the inspection of the control system can be improved.
Further, since the control system inspection is performed in a state where the brake cylinders 42FL and FR are communicated with the master cylinder 62 and the brake cylinders 52RL and RR are communicated with the reservoir 78, the hydraulic pressure in the common passage 152 is maintained by the holding valve. Even if it flows out through any of 153, it is returned to the reservoir 78 (the reservoir 78 through the master cylinder 62). Therefore, the operation of the hydraulic brakes 40 and 50 is prevented, and dragging is prevented.
Further, since the brake cylinders 42FL and FR of the left and right front wheels 2 and 4 are communicated with the master cylinder 62, when the brake pedal 60 is depressed during the control system inspection, the right and left front wheels 2 and 4 The hydraulic brakes 40FL and FR can be operated.

In the above embodiment, the control system inspection is stopped when the brake pedal 60 is operated during the control system inspection. However, the control system inspection can be continued. Since the common passage 152 is cut off from the brake cylinders 42FL and FR of the left and right front wheels 2 and 4, and is cut off from the pressure increasing mechanism 100, the common passage 152 is generated even if hydraulic pressure is generated in the master cylinder 62. This is because there is no influence on the hydraulic pressure of the liquid.
In addition, when the first set pressure is substantially the same value as the upper limit value of the pressure detectable area determined by the brake cylinder pressure sensor itself or larger than the upper limit value of the pressure detectable area, the brake cylinder pressure sensor 226 is used. It is possible to perform inspection over almost the entire pressure detectable range. In other words, the first set pressure can be determined such that the abnormality determination threshold value is a value near the upper limit value of the pressure detectable range.

Furthermore, in the above-described embodiment, the case where the supply current to the solenoid 186 of the pressure-increasing linear control valve 172 is rapidly increased has been described, but it can also be increased gradually.
As shown in FIG. 3B, it can be seen that the pressure difference between the front and rear is controlled to a small value by the pressure increase linear control valve 172 as the supply current increases. That is, as indicated by the solid line in FIG. 5B, if the supply current amount I to the solenoid 186 is gradually increased, the control pressure (brake cylinder hydraulic pressure) should gradually increase.
Therefore, in this embodiment, the detected value of the brake cylinder pressure sensor 226 when the amount of current supplied to the solenoid 186 of the pressure-increasing linear control valve 172 when the control system is normal is gradually stored. It is determined whether or not the number gradually increases.
If the detected value of the brake cylinder pressure sensor 226 increases gradually and properly, the control system is normal. Otherwise, the control system is not normal (for example, the brake cylinder pressure sensor 226, pressure-increasing linear control). At least one of the valves 172 is abnormal).
In this embodiment, all the pressure reducing valves 156FL, FR, RL, RR are in communication, and all the brake cylinders 42FL, FR, RL, RR in the front, rear, left, and right are in communication with the reservoir 78. System inspection is performed. Note that the master shut-off valves 194FL and FR are closed.

An example of this case will be described with reference to the flowchart of FIG.
In the present embodiment, the supply current to the pressure-increasing linear control valve 172 is gradually increased to a magnitude (set current amount Is) at which the differential pressure before and after becomes zero.
Further, the detected value Pwc of the brake cylinder pressure sensor 226 is stored until the current amount I reaches the set current amount Is, and when the set current amount Is is reached, the stored detected value Pwc is processed and appropriately It is determined whether or not the number has increased gradually.
As a result of the processing, when the detected value of the brake cylinder pressure sensor 226 is gradually increasing properly, it is determined that the control system is normal, and otherwise, it is determined that the control system is abnormal. .
If the detected value PACC of the accumulator pressure sensor 224 is larger than the first set pressure PACC0 in the closed state of the pressure increasing linear control valve 172, the holding valve 153 and the pressure increasing mechanism cutoff valve 192 are closed in S31. All the pressure reducing valves 156FL, FR, RL, RR are opened.
In S32, the amount of current I supplied to the solenoid 186 of the pressure-increasing linear control valve 172 is increased by ΔI. In S33, it is determined whether or not the current amount I supplied to the solenoid 186 has reached the set current amount Is. If the set current amount Is has not been reached, the detected value of the brake cylinder pressure sensor 226 is stored in S34 and S35, and the current increase wait flag is turned ON in S35.
Next, when this program is executed, since the current increase wait flag is ON, the determination in S36 is YES, so in S32, the supply current is increased by the set amount ΔI. S32-35 and 36 are repeatedly executed.
In the meantime, when the supply current reaches the set current amount Is, the determination in S33 is YES, the stored data is processed, and in S37, it is determined whether or not it is gradually increasing. For example, if it is gradually increasing as indicated by the solid line in FIG. 5B, it is determined in S38 that the control system is normal. On the other hand, for example, as indicated by the broken line in FIG. 5 (b), when it is not gradually increasing properly (for example, when the increasing gradient changes rapidly or the increasing gradient is very small), In S39, it is determined to be abnormal. Thereafter, in S40, the current increase wait flag is turned OFF, and thereafter S15 to S19 are executed in the same manner.
As described above, in this embodiment, it is determined whether or not the detected value of the brake cylinder pressure sensor 226 is properly gradually increased with the gradual increase of the current, and the brake cylinder pressure sensor 226 and the pressure increasing linear control are determined. Whether or not the valve 172 is normal can be detected in more detail.

<Brake cylinder fluid pressure control>
Then, the hydraulic pressures of the brake cylinders 42 and 52 are controlled based on the result of the initial check, and the brake hydraulic pressure control program represented by the flowchart of FIG. 6 is executed at predetermined time intervals. .
In S51, if there is a braking request, that is, if the brake switch 218 is ON, or if there is a request for operating the automatic brake, it is determined that there is a braking request, and the determination is YES. The automatic brake may be operated in traction control, vehicle stability control, inter-vehicle distance control, and collision avoidance control. When these control start conditions are satisfied, a braking request may be made.
If there is a braking request, it is detected in S52 whether there is a possibility of liquid leakage. In the present embodiment, it is assumed that there is a possibility of liquid leakage when the level warning 228 is ON.
If there is no possibility of liquid leakage, a determination result as to whether or not the control system is abnormal is read in S53.
If both determinations are NO, regeneration cooperative control is performed in S54.
If the control system is abnormal, the determination in S53 is YES, and in S55, no current is supplied to the solenoids of all the valves, thereby returning the original position. Further, the pump motor 92 is kept in a stopped state.
If it is detected that there is a possibility of liquid leakage, the determination in S52 is YES, and in S56, the hydraulic pressure of the master cylinder 62 is supplied to the brake cylinders 42 of the left and right front wheels 2, 4, and the left and right rear wheels 46, The hydraulic pressure controlled by the output hydraulic pressure control valve device 178 is supplied to the 48 brake cylinders 52. Since it is rare that both the abnormality of the control system and the possibility of liquid leakage occur, the control system is normal even if there is a possibility of liquid leakage, the control of each valve, the drive of the pump motor 92 Is considered possible.
When the electric system is abnormal, no current is supplied to the brake system, so the valve is returned to the original position and the pump motor 92 is held in a stopped state. The state is the same as when the control system is abnormal.
In the present embodiment, the automatic brake is not operated when the control system is abnormal or when there is a possibility of liquid leakage.

1) When the system is normal The hydraulic pressures of the brake cylinders 42 and 52 of the left and right front and rear wheels 2, 4, 46, and 48 are controlled by the output hydraulic pressure control valve device 178. In principle, regenerative cooperative control is performed. .
In the regenerative cooperative control, the total braking torque, which is the sum of the regenerative braking torque applied to the driving wheels 2 and 4 and the friction braking torque applied to both the driving wheels 2 and 4 and the driven wheels 46 and 48, is the total required braking torque. The control is performed as follows.
The total required braking torque is acquired based on detection values of the stroke sensor 220 and the master cylinder pressure sensor 222 (braking torque requested by the driver), or acquired based on the running state of the vehicle (traction control). , Braking torque necessary for vehicle stability control), information obtained from the inter-vehicle control ECU 242, the collision avoidance ECU 244, and the like. Then, the information supplied from the hybrid ECU 58 (the power generation side upper limit value that is the upper limit value of the regenerative braking torque determined based on the rotation speed of the electric motor 20, the power storage that is the upper limit value determined based on the charging capacity of the pressure accumulator 22, etc. Side upper limit value) and the total required braking torque (requested value) described above are determined as the required regenerative braking torque, and information representing the required regenerative braking torque is supplied to the hybrid ECU 58.
Hybrid ECU 58 outputs information representing the required regenerative braking torque to motor ECU 28. The motor ECU 28 outputs a control command to the power converter 26 so that the braking torque applied to the left and right front wheels 2 and 4 by the electric motor 20 becomes the required regenerative braking torque. The electric motor 20 is controlled by the power converter 26.
Information representing the operating state such as the actual rotational speed of the electric motor 20 is supplied from the motor ECU 28 to the hybrid ECU 58. The hybrid ECU 58 obtains the actual regenerative braking torque actually obtained based on the actual operating state of the electric motor 20, and outputs information representing the actual regenerative braking torque value to the brake ECU 56.
The brake ECU 56 determines the required hydraulic braking torque based on a value obtained by subtracting the actual regenerative braking torque from the total required braking torque, so that the brake cylinder hydraulic pressure approaches the target hydraulic pressure corresponding to the required hydraulic braking torque. The pressure-increasing linear control valve 172, the pressure-decreasing linear control valve 176, and the like are controlled.

In the regenerative cooperative control, as shown in FIG. 7, in principle, the holding valves 153FL, FR, RL, RR of the front, rear, left and right wheels 2, 4, 46, 48 are all opened, and the pressure reducing valves 156FL, FR , RL, RR are all closed. Further, the master cutoff valves 194FL and FR are closed, the simulator control valve 202 is opened, and the pressure increase mechanism cutoff valve 192 is closed. With the common passage 152 cut off from the pressure increase mechanism 100 and the brake cylinders 42FL and FR of the left and right front wheels 2 and 4 cut off from the master cylinder 62, the pressure increase linear control valve 172 and the pressure reduction linear control valve 176 are controlled. The hydraulic pressure in the common passage 152 is controlled, and the hydraulic pressures in the four-wheel brake cylinders 42 and 52 are controlled.
In this state, when the slip of the wheels 2, 4, 46, 48 becomes excessive and the antilock control start condition is satisfied, the holding valve 153 and the pressure reducing valve 156 are opened and closed independently, and the brake cylinders 42 are opened and closed. , 52 is controlled. The slip state of the front, rear, left and right wheels 2, 4, 46, 48 is set to an appropriate state.
Further, in a vehicle in which regenerative cooperative control is not performed, such as when the hydraulic brake system is mounted on a vehicle that does not include the electric drive device 8, the total required braking torque and the hydraulic braking torque are equalized. The output hydraulic pressure control valve device 178 is controlled.

2) When the control system is abnormal (when the electrical system is abnormal)
As shown in FIG. 8, each valve is returned to its original position.
The pressure-increasing linear control valve 172 and the pressure-decreasing linear control valve 176 are closed when no current is supplied to the solenoid 184, and the power hydraulic pressure source 64 is shut off from the common passage 152.
Further, since the pressure increase mechanism cutoff valve 192 is opened, the pressure increase mechanism 100 is communicated with the common passage 152.
Further, since the holding valves 153FR and RL are in a closed state and the holding valves 153FL and RR are in an open state, the brake cylinders 42FL and 52RR of the left front wheel 2 and the right rear wheel 48 are communicated with the common passage 152, and the right front wheel 4, the brake cylinders 42FR and 52RL of the left rear wheel 46 are shut off.

By operating the brake pedal 60, hydraulic pressure is generated in the pressurizing chambers 70 and 72 of the master cylinder 62.
The hydraulic pressure in the pressurizing chamber 72 is supplied to the pressure increasing mechanism 100, and the pressure increasing mechanism 100 is operated. As the stepped piston 104 advances, the small-diameter side chamber 112 is cut off from the large-diameter side chamber 110 and the hydraulic pressure is increased. The valve opening member 125 is advanced, and the high pressure supply valve 116 is opened. Further, high-pressure hydraulic fluid is supplied from the accumulator 66 to the high-pressure chamber 114 through the high-pressure check valve 132 and then supplied to the small-diameter side chamber 112. The hydraulic pressure (servo pressure) in the small-diameter side chamber 112 is made higher than the hydraulic pressure in the master cylinder 62 (the brake operation force is boosted), and is supplied to the common passage 152 via the pressure-increasing mechanism cutoff valve 192 in the open state. It is supplied to the brake cylinders 42FL and 52RR for the left front wheel and the right rear wheel via the holding valves 153FL and RR. The hydraulic pressures in the brake cylinders 42Fl and 52RR for the left front wheel and the right rear wheel are servo pressures.
In this case, since the master cutoff valve 194FL corresponding to the left front wheel 2 is in the closed state, the servo pressure supplied to the brake cylinder 42FL is prevented from flowing out to the master cylinder 62. Thereby, the hydraulic brake 40FL can be operated satisfactorily.

Since the pump device 65 is in a stopped state, the hydraulic pressure of the accumulator 66 becomes low over time. When the hydraulic pressure in the accumulator 66 becomes equal to or lower than the hydraulic pressure in the high-pressure chamber 114, the flow of hydraulic fluid between the accumulator 66 and the high-pressure chamber 114 is blocked, so that the stepped piston 104 is prevented from moving forward. Further, the stepped piston 104 may be prevented from moving forward by contacting the stopper. In any case, the hydraulic pressure in the small-diameter side chamber 112 does not increase any more, and the mechanical pressure intensifier 134 cannot exhibit the boosting function.
On the other hand, when the operating force of the brake pedal 10 is increased and the hydraulic pressure in the pressurizing chamber 72 of the master cylinder 62 becomes higher than the hydraulic pressure in the small-diameter side chamber 112, the mechanical pressure booster bypass passage 136 and the manual check valve 138 are passed through. It is supplied to the small-diameter side chamber 112 (the output side of the mechanical pressure intensifier 134) and supplied to the brake cylinders 42FL and 52RR of the left front wheel 2 and the right rear wheel 48 via the pressure intensifying mechanism cutoff valve 192 and the holding valves 153FL and RR. .
In this case, since the hydraulic pressure in the pressurizing chamber 72 of the master cylinder 62 is not boosted, the hydraulic pressures of the brake cylinders 42FL and 52RR of the left front wheel 2 and the right rear wheel 48 are set to the master cylinder pressure. The

Further, since the holding valves 153FR and RL are closed, the hydraulic pressure in the pressurizing chamber 72 is not supplied to the brake cylinders 42FR and 52RL of the right front wheel 4 and the left rear wheel 46.
The amount of hydraulic fluid that can be supplied from one pressurizing chamber 72 of the master cylinder 62 is determined. Therefore, when the number of brake cylinders to be supplied increases, there arises a problem that the hydraulic pressure of the brake cylinder cannot be sufficiently increased. On the other hand, since the pressure receiving area of the piston is larger in the front wheel brake cylinder 42 than in the rear wheel brake cylinder 52, the amount of hydraulic fluid consumed in the brake cylinder increases when the hydraulic pressure is the same.
From these circumstances, if the hydraulic pressure is supplied from the pressurizing chamber 72 to the brake cylinders 42FL and FR of the left and right front wheels 2 and 4, there is a risk of insufficient braking force.
On the other hand, the hydraulic pressure in the pressurizing chamber 72 can be supplied to two wheels on the same side in the width direction, for example, the brake cylinders 42FL and 52RL of the left front wheel 2 and the left rear wheel 46. However, in that case, a yaw moment may occur.
Therefore, if hydraulic fluid is supplied to the brake cylinders 42FL and 52RR of the two wheels (left front wheel 2 and right rear wheel 48) that are diagonal to each other, the two fluids are made less likely to cause yaw moment. The pressure brakes 40FL and 50RR can be operated satisfactorily.

Further, hydraulic pressure is supplied to the brake cylinder 42FR of the right front wheel 4 from the pressurizing chamber 70 of the master cylinder 62 through the master cutoff valve 194FR in the open state.
No hydraulic pressure is supplied to the brake cylinder 52RL of the left rear wheel 46.
Thus, in this embodiment, the hydraulic pressures of the pressure increase mechanism 100 and the master cylinder 62 are supplied to the three-wheel brake cylinders 42FL, FR, and 52RR when the control system is abnormal and the electric system is abnormal. As a result, the braking force of the entire vehicle can be increased as compared with the case where hydraulic pressure is supplied to the two-wheel brake cylinder.
Further, while the pressure increasing mechanism 100 is in operation, servo pressure is supplied to the left front wheel 2, master pressure is supplied to the right front wheel 4, and servo pressure is supplied to the right rear wheel 48. And the braking force difference between the two and the yaw moment can be further reduced.

3) When it is detected that there is a possibility of liquid leakage As shown in FIG. 9, the holding valves 153FL, FR of the left and right front wheels 2, 4 are closed, and the holding valves 153RL, RR of the left and right rear wheels 46, 48 are closed. Is opened. Further, the master cutoff valves 194FL and FR are opened, the pressure increase mechanism cutoff valve 192 is closed, and the simulator control valve 202 is closed. Further, all the pressure reducing valves 156 are closed. As described above, the hydraulic pressures of the brake cylinders 42RL and RR of the left and right rear wheels 46 and 48 are set as the control pressure, and the hydraulic pressures of the brake cylinders 42FL and FR of the left and right front wheels 2 and 4 are set as the master cylinder pressure.
Since the holding valves 153FL and FR of the left and right front wheels 2 and 4 are cut off, the brake cylinders 42FL and FR of the left and right front wheels 2 and 4 are cut off from each other. Further, the brake cylinders 42FL, FR of the left and right front wheels 2, 4 and the brake cylinders 52RL, RR of the left and right rear wheels 46, 48 are blocked. Thus, the brake cylinders of the front and rear wheels are shut off from each other, and the brake cylinders of the left front wheel 2 and the right front wheel 4 are shut off on the front wheel side. That is, the three brakes (brake system 250FL including the left front wheel brake cylinder 42FL), (brake system 250FR including the right front wheel brake cylinder 42FR), and (brake system 250R including the left and right rear wheel brake cylinders 52FL and RR). The systems are cut off from each other. As a result, even if liquid leakage occurs in one of these three brake systems, the other brake systems are not affected.
In addition, since the pressure increase mechanism cutoff valve 192 is closed, it is possible to prevent the hydraulic fluid supplied from the power hydraulic pressure source 64 to the common passage 152 from flowing to the pressure increase mechanism 100. That is, in the present embodiment, the presence or absence of the possibility of liquid leakage is detected, but the position of liquid leakage is not specified. If there is a fluid leak in the brake system 250FL, a high hydraulic pressure cannot be supplied to the large-diameter side chamber 130, and the pressure-increasing mechanism 100 is held in an inoperative state. The stepped piston 104 is in the retracted end position, and the small diameter side chamber 112 and the large diameter side chamber 110 are communicated with each other by the communication passage 130. In this case, if the pressure-increasing mechanism shut-off valve 192 is in the open state, the common passage 152 and the pressurizing chamber 72 are communicated with each other via the communication passage 130, and the hydraulic pressure in the common passage 152 may flow backward. . On the other hand, if the pressure-increasing mechanism shut-off valve 192 is closed, it is possible to satisfactorily prevent the hydraulic fluid in the common passage 152 from flowing into the master cylinder 62, and the brakes for the left and right rear wheels 46, 48 can be prevented. It becomes possible to supply control pressure to the cylinders 52RL and RR.
In this embodiment, the brake system 250FR includes a brake cylinder 42FR, a master passage 76, a pressurizing chamber 70, a storage chamber 80, and the like, and the brake system 250FL includes a brake cylinder 42FL, a master passage 74, a pressurizing chamber, and the like. The brake system 250R includes the brake cylinders 52RL and RR, the individual passages 150RL and RR, the power hydraulic pressure source 64, the storage chamber 84, and the like.

4) When the hydraulic brake is released When the brake operation is released, the current is not supplied to the solenoids of all the valves, thereby returning the original position of FIG. Further, in the pressure increasing mechanism 100, the stepped piston 104 is returned to the retracted end, and the large-diameter side chamber 110 and the small-diameter side chamber 112 are communicated with each other through the liquid passage 130.
The hydraulic pressure in the brake cylinder 42FR for the right front wheel is returned to the master cylinder 62 and the reservoir 78 through the master cutoff valve 194FR in the open state, and the hydraulic pressure in the brake cylinder 42FL in the left front wheel 2 is in the open state. The pressure is returned to the master cylinder 62 and the reservoir 78 through the pressure increase mechanism cutoff valve 192 and the communication path 130. Similarly, the hydraulic pressure of the brake cylinder 52RR of the right rear wheel 48 is also returned to the reservoir 78 via the holding valve 153RR, the pressure increasing mechanism cutoff valve 192, and the pressure increasing mechanism 100. The hydraulic fluid in the brake cylinder 52 of the left rear wheel 46 is returned to the reservoir 78 via the pressure reducing valve 156RL that is open.
As for the brake cylinder 52RL of the left rear wheel 46, the holding valve 153RL is normally closed in order to prevent the hydraulic fluid of the master cylinder 62 and the pressure increasing mechanism 100 from being supplied when the control system is abnormal (electrical abnormality). It is an electromagnetic control valve. Therefore, when releasing the brake, the brake cylinder 52FL is disconnected from the common passage 152, and the hydraulic fluid cannot be returned to the master cylinder 62 via the pressure increasing mechanism 100. On the other hand, since the pressure reducing valve 156RL is a normally open electromagnetic opening / closing valve, the hydraulic fluid of the brake cylinder 52RL can be returned to the reservoir 78 via the pressure reducing valve 156RL. Further, when the pressure reducing valve 156 is a normally open electromagnetic opening / closing valve, there is a problem that the current must be continuously supplied to the solenoid in the operation state of the hydraulic brakes 40 and 50, and the power consumption increases. On the other hand, in the present embodiment, since there is one normally open pressure reducing valve 156RL, an increase in power consumption due to this can be suppressed.

As described above, in the present embodiment, the hydraulic pressures of the brake cylinders 42 and 52 are controlled according to the result of the initial check.
When the control system is abnormal (electrical system abnormality), the hydraulic pressure higher than the hydraulic pressure of the master cylinder 62 can be supplied to the brake cylinders 42FL and 52RR by the operation of the pressure increasing mechanism 100. Further, since the hydraulic pressure is supplied from the master cylinder 62 to the brake cylinder 42FR of the right front wheel 4, the three-wheel hydraulic brakes 40FL, FR, 50RR can be operated when the electric system is abnormal. As a result, a shortage of braking force can be resolved as compared with the case where the two-wheel hydraulic brake is operated. Further, since the servo pressure is supplied to the brake cylinder of the wheel at the diagonal position, it is possible to make the yaw moment less likely to occur.
When there is a possibility of liquid leakage, the brake systems 250FL, FR, R are cut off from each other. Therefore, even if liquid leakage occurs in one of the three brake systems 250FL, FR, R, it is possible to favorably avoid the influence of the other brake systems. In a brake system in which no fluid leaks, the hydraulic brake can be operated more reliably.
In this embodiment, the holding valves 153FL and FR function as a left / right shut-off valve and a front / rear shut-off valve. Therefore, a dedicated front / rear shut-off valve and left / right shut-off valve are not required, and the cost can be reduced accordingly.

In the hydraulic brake system configured as described above, the brake hydraulic pressure control device is configured by a portion that stores the brake hydraulic pressure control program represented by the flowchart of FIG. Further, the holding valves 153FL, FR, RL, RR, and the pressure increase mechanism cutoff valve 192 constitute a communication cutoff device. A pressure-increasing mechanism communication blocking unit is configured by the pressure-increasing mechanism cutoff valve 192 and the like.
A control system inspection apparatus is constituted by a part for storing and executing the initial check program represented by the flowcharts of FIGS. Of these, the first control system inspecting unit is configured by the part that stores S8-13, the part that executes S8-13, and the like, and the second control system inspecting unit is configured by the part that stores S32-39, the part that executes S7, and the like. (Portion for holding the holding valve 153 and the pressure increasing mechanism cutoff valve 192 in the closed state), S8 to 13, S31 (portion for holding the holding valve 153 and the pressure increasing mechanism cutoff valve 192 in the closed state), portions for storing 32-39 The third control system inspecting part is configured by the part to be executed, etc., and S7 (the part that opens the rear wheel pressure reducing valve 156 and the master shut-off valve 194), S8 to 13, S31 (the pressure reducing valve 156 is opened) ), A portion for storing 32 to 39, a portion for executing, and the like constitute a fourth control system inspection unit.
Further, the fifth control system inspecting unit is configured by a part for storing S1, S8 to 13, 32 to 37, a part for executing the part, and the like. The control system abnormality detection device can be considered as a control system abnormality detection unit.

The structure of the brake circuit is not limited to that in the above embodiment. For example, a front / rear shut-off valve can be provided between the connection portion of the individual passage 150RR of the common passage 152 and the connection portion of the individual passage 150FL. In this case, the communication cutoff device is constituted by the rear wheel holding valves 153RL and RR and the front and rear cutoff valves.
Further, the control system inspection condition is not limited to that of the above embodiment. For example, there is a low possibility that the condition including that the rotational speed of the engine 16 is equal to or higher than the set number, or that the volume of the audio device is equal to or higher than the set volume, or that the brake pedal 60 is operated. Or a condition including the absence of a braking request. The set number of rotations of the engine 16 can be set so that the sound generated by the engine 16 is higher than the operating sound generated in the control system inspection or the operating sound generated in the control system inspection is not bothering. The setting volume of the audio device is the same, and can be set to a level that does not bother the operation sound generated in the control system inspection. In many cases, the brake pedal 60 is not operated again within a set time after the operation is released. The control system can be inspected within the set time. Furthermore, since there is a possibility that the automatic brake is operated, the control system can be inspected when there is no braking request.

  Further, the pressure increasing mechanism 100 and the output hydraulic pressure control valve device 178 are not essential. The power hydraulic pressure source 64 may be used only for operating the pressure-increasing mechanism 100. In addition to the above-described embodiments, the present invention can be modified in various ways based on the knowledge of those skilled in the art. It can be implemented in an improved manner.

  40, 50: Hydraulic brake 42, 52: Brake cylinder 54: Hydraulic pressure control unit 56: Brake ECU 60: Brake pedal 62: Master cylinder 64: Powered hydraulic pressure source 66: Accumulator 74, 76: Master shut-off valve 100: Pressure increasing mechanism 150: Individual passage 152: Common passage 153: Holding valve 156; Pressure reducing valve 170: Control pressure passage 172: Pressure increasing linear control valve 176: Pressure reducing linear control valve 178: Output hydraulic pressure control valve device 190: Servo pressure passage 192: Pressure increasing mechanism cutoff valve 218: Brake switch 220: Stroke sensor 222: Master cylinder pressure sensor 224: Accumulator pressure sensor 226: Brake cylinder pressure sensor 228: Level warning

Claims (8)

A hydraulic brake that is provided on each of the plurality of wheels of the vehicle and is operated by the hydraulic pressure of the brake cylinder to suppress rotation of the wheels;
A hydraulic pressure source including an accumulator for generating a hydraulic pressure by supplying electric energy and storing the generated hydraulic pressure ;
A common passage to which the hydraulic fluid pressure source is connected and to which the brake cylinders of the plurality of hydraulic brakes are connected;
An output hydraulic pressure control valve provided in a control pressure passage connecting the common passage and the power hydraulic pressure source, and controlling an output hydraulic pressure of the power hydraulic pressure source to supply the common passage;
A hydraulic pressure source hydraulic pressure sensor for detecting hydraulic pressure on the power hydraulic pressure source side of the output hydraulic pressure control valve;
A control pressure sensor for detecting a fluid pressure on the common passage side of the output fluid pressure control valve;
A connection portion of the common passage with the control pressure passage, the control pressure sensor, and the plurality of brake cylinders, and the connection portion, the control pressure sensor, and the plurality of brake cylinders communicate with each other. A communication blocking device for blocking,
In a state where the connection portion and the control pressure sensor and the plurality of brake cylinders are in communication with each other by the communication cutoff device, the hydraulic pressure in the common passage is controlled by controlling at least the output hydraulic pressure control valve. A brake system including a brake fluid pressure control device that controls fluid pressure of the plurality of brake cylinders,
The output hydraulic pressure when the detected value of the hydraulic pressure source hydraulic pressure sensor is larger than a first set pressure in a state where the connection portion and the control pressure sensor are disconnected from the plurality of brake cylinders by the communication cutoff device. When the control valve is switched from the closed state to the open state, and then the detected value of the control pressure sensor increases to an abnormality determination threshold value determined by the first set pressure, the control system of the brake system is normal. A brake system , characterized in that a first control system inspection unit is provided . The brake system includes: (a) a manual hydraulic pressure source that generates hydraulic pressure by a driver's brake operation; and (b) a hydraulic fluid source of the manual hydraulic pressure source that utilizes the hydraulic pressure of the power hydraulic pressure source. Including a pressure-increasing mechanism that can output by increasing the pressure,
The pressure increasing mechanism is connected to the common passage,
The communication blocking device includes a pressure-increasing mechanism communication blocking unit for communicating or blocking the connection unit and the control pressure sensor and the pressure-increasing mechanism; and
Whether the control system is normal when the first control system inspecting unit is disconnected from the connection unit and the control pressure sensor from the plurality of brake cylinders and the pressure increasing mechanism by the communication cutoff device. brake system according to claim 1 including a third control system checking unit that performs Kano inspection. One or more of the plurality of brake cylinders are connected to the common passage via individual passages, the pressure increasing mechanism is connected via a servo pressure passage, and the communication cut-off device includes: (a) an upstream individual control valve provided in each of the individual passages; (b) a pressure-increasing mechanism communication cutoff valve provided in the servo pressure passage; and (c) all of the upstream individual control valves. A valve control unit that switches the pressure-increasing mechanism shut-off valve between an open state and a closed state, respectively, and the third control system inspection unit includes all the upstream-side individual control valves and the pressure-increasing mechanism communication shut-off valve. The brake system according to claim 2 , wherein the control system is inspected in a closed state. In the first control system inspection unit, the plurality of brake cylinders and the low pressure source are in communication with each other, and the plurality of brake cylinders are disconnected from the connection unit and the control pressure sensor by the communication cutoff device The brake system according to any one of claims 1 to 3 , further comprising a fourth control system inspecting unit that inspects whether or not the control system is normal . When the control system inspection device satisfies a predetermined control system inspection condition, the control system inspection device includes a fifth control system inspection unit that performs an inspection as to whether or not the control system is normal . The brake system according to any one of claims 1 to 4 , comprising at least one of the hydraulic brake being in an inactive state and a traveling speed of the vehicle being a set speed or higher. The output hydraulic pressure control valve is a linear control valve capable of controlling the differential pressure before and after itself to a smaller value when the supply current to the solenoid is small,
The braking system is further the state where the connecting portion and the control pressure sensor is cut off from said plurality of brake cylinders by connection cutoff device, with an increase of the supply current to the solenoid, the control pressure sensor The brake system according to claim 1, further comprising a second control system inspection unit that determines that the control system of the brake system is normal when the detected value increases . A hydraulic brake that is provided on each of the plurality of wheels of the vehicle and is operated by the hydraulic pressure of the brake cylinder to suppress rotation of the wheels;
  A hydraulic pressure source including an accumulator for generating a hydraulic pressure by supplying electric energy and storing the generated hydraulic pressure;
  A common passage to which the hydraulic fluid pressure source is connected and to which the brake cylinders of the plurality of hydraulic brakes are connected;
  An output hydraulic pressure control valve provided in a control pressure passage connecting the common passage and the power hydraulic pressure source, and controlling an output hydraulic pressure of the power hydraulic pressure source to supply the common passage;
  A hydraulic pressure source hydraulic pressure sensor for detecting hydraulic pressure on the power hydraulic pressure source side of the output hydraulic pressure control valve;
  A control pressure sensor for detecting a fluid pressure on the common passage side of the output fluid pressure control valve;
  A connection portion of the common passage with the control pressure passage, the control pressure sensor, and the plurality of brake cylinders, and the connection portion, the control pressure sensor, and the plurality of brake cylinders communicate with each other. A communication blocking device for blocking,
  In a state where the connection portion and the control pressure sensor and the plurality of brake cylinders are in communication with each other by the communication cutoff device, the hydraulic pressure in the common passage is controlled by controlling at least the output hydraulic pressure control valve. A brake fluid pressure control device for controlling fluid pressures of the plurality of brake cylinders;
A brake system comprising:
  The output hydraulic pressure control valve includes: (a) a valve seat; (b) a valve element capable of approaching and separating from the valve seat; and (c) the valve element seated on the valve seat. A spring for applying an elastic force in a direction to be driven, and (d) a solenoid for applying an electromagnetic driving force in a direction to separate the valve element from the valve seat by a supply current to the valve element, Is a linear control valve that can be controlled to a smaller value when the amount of current supplied to the solenoid is large,
  In the brake system, the connection pressure and the control pressure sensor are disconnected from the plurality of brake cylinders by the communication cutoff device, and the detected value of the control pressure sensor increases as the supply current to the solenoid increases. A brake system comprising: a second control system inspection unit that determines that the control system of the brake system is normal when the value of the brake system increases. A hydraulic brake that is provided on each of the plurality of wheels of the vehicle and is operated by the hydraulic pressure of the brake cylinder to suppress rotation of the wheels;
  A hydraulic pressure source including an accumulator for generating a hydraulic pressure by supplying electric energy and storing the generated hydraulic pressure;
  A common passage to which the hydraulic fluid pressure source is connected and to which the brake cylinders of the plurality of hydraulic brakes are connected;
  An output hydraulic pressure control valve provided in a control pressure passage connecting the common passage and the power hydraulic pressure source, and controlling an output hydraulic pressure of the power hydraulic pressure source to supply the common passage;
  A hydraulic pressure source hydraulic pressure sensor for detecting hydraulic pressure on the power hydraulic pressure source side of the output hydraulic pressure control valve;
  A control pressure sensor for detecting a fluid pressure on the common passage side of the output fluid pressure control valve;
  A connection portion of the common passage with the control pressure passage, the control pressure sensor, and the plurality of brake cylinders, and the connection portion, the control pressure sensor, and the plurality of brake cylinders communicate with each other. A communication blocking device for blocking,
  In a state where the connection portion and the control pressure sensor and the plurality of brake cylinders are in communication with each other by the communication cutoff device, the hydraulic pressure in the common passage is controlled by controlling at least the output hydraulic pressure control valve. A brake fluid pressure control device for controlling fluid pressures of the plurality of brake cylinders;
Including brake system,
  After the output hydraulic pressure control valve is switched to the open state in a state where the connection portion and the control pressure sensor are disconnected from the plurality of brake cylinders by the communication cutoff device, the detection value of the control pressure sensor is: A control system abnormality detection unit for detecting that the output hydraulic pressure control valve included in the control system of the brake system is abnormal when the detection value of the hydraulic pressure source hydraulic pressure sensor is low; Brake system to do.

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