JP2012229020A - Brake device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brake device that can obtain pressure reduction performance on a low-μ road face while suppressing the suction resistance of a pump.SOLUTION: The brake device comprises a gate-in valve which performs an opening and closing operation related to master cylinder pressure to a suction oil passage which connects a master cylinder and the suction side of a rotating pump, and pressure at the suction side of the pump. The rotating pump sucks a brake fluid via the gate-in valve which in the opening and closing operation when the master cylinder pressure acts on the pump.

Description

  The present invention relates to the technical field of brake devices.

  Conventionally, a technique described in Patent Document 1 is known as a technique in which an internal reservoir for temporarily storing brake fluid from a wheel cylinder is provided in a brake device. The internal reservoir described in this publication is composed of a ball, a pin, a piston, and a spring, and has a function of regulating pressure applied from the master cylinder to the pump suction side in addition to storing brake fluid.

JP 2007-238095 A

  In the brake device described in Patent Document 1 described above, in order to establish an operation even for a high master cylinder pressure, the spring force provided in the reservoir is set large, or the ball pressure receiving area is set small. There is a need to. When the spring force is set large, the brake fluid pressure that can be reduced from the wheel cylinder is increased, and the pressure reduction performance on the low μ road surface cannot be obtained. On the other hand, if the pressure receiving area of the ball is set to be small, the suction resistance when sucking in brake fluid from the master cylinder side by pumping up like an automatic brake is increased even if the pressure reduction performance on the low μ road surface can be secured. However, the boosting performance is degraded. In other words, there was a contradictory relationship.

  The present invention has been made paying attention to the above problem, and it is an object of the present invention to provide a brake device capable of obtaining pressure reduction performance on a low μ road surface while suppressing suction resistance of the pump.

  In order to achieve the above object, in the present invention, the intake oil passage connecting the master cylinder and the suction side of the rotary pump is provided with a gate-in valve that opens and closes in relation to the master cylinder pressure and the pressure on the pump suction side. The type pump sucks brake fluid through a gate-in valve that opens and closes when the master cylinder pressure is applied.

  In addition to the reservoir for storing brake fluid decompressed from the wheel cylinder, a low-μ road surface is provided while suppressing the suction resistance of the pump by providing a gate-in valve that operates in relation to the master cylinder pressure and the pressure on the pump suction side. The pressure reduction performance can be obtained.

1 is a hydraulic circuit diagram of a brake system to which a brake device of Example 1 is applied. 1 is a schematic diagram illustrating a configuration of a gate-in valve 2 according to a first embodiment. 6 is a schematic diagram illustrating a configuration of an internal reservoir described in Patent Document 1. FIG. It is a characteristic view showing the relationship between hydraulic pressure and spring force (load). 3 is a time chart showing the pump-up action of the first embodiment. It is a hydraulic-circuit figure of the brake system to which the brake device of Example 2 is applied. It is a hydraulic-circuit figure of the brake system to which the brake device of Example 3 is applied.

  Hereinafter, the best embodiment of the present invention will be described with reference to the drawings.

  The brake device according to the first embodiment includes a hydraulic unit 31 that includes a motor, a pump, a solenoid valve, a sensor, and the like, and is interposed between a master cylinder M / C and a wheel cylinder W / C. This is an electro-mechanical integrated brake device that is integrally attached to the hydraulic unit 31 and includes a control unit CU that controls each element. Note that the configuration is not limited to a mechanical / electrical integrated configuration, and the hydraulic unit 31 and the control unit CU may be configured separately and are not particularly limited.

[Configuration of brake piping]
FIG. 1 is a hydraulic circuit diagram of a brake system to which the brake device of the present invention is applied. The portion enclosed by the one-dot chain line in the figure is the hydraulic unit 31. This brake system has a piping structure called X piping, which consists of two systems, a P system and an S system. The P system is connected to the wheel cylinder W / C (FL) for the left front wheel and the wheel cylinder W / C (RR) for the right rear wheel. The wheel cylinder W / C (FR) for the right front wheel is connected to the S system. The wheel cylinder W / C (RL) on the left rear wheel is connected. Each of the P system and the S system is provided with a pump PP and a pump PS, and the pump PP and the pump PS are driven by one motor M. In addition, you may comprise from one motor and one pump, a plunger pump and a gear pump may be mounted, and it does not specifically limit.

  The brake pedal BP is provided with a brake switch BS that detects the operation state of the brake pedal BP. The brake pedal BP is connected to the master cylinder M / C via the input rod 1. Master cylinder M / C and the suction side of pumps PP and PS (hereinafter referred to as pump P) are connected by pipes 11P and 11S (hereinafter referred to as pipe 11 (corresponding to the suction oil path)). ing. On each pipeline 11, gate-in valves 2P and 2S (corresponding to a gate-in valve and a differential pressure valve) are provided. Of the pipelines 11, the pipeline 11 on the master cylinder side of the gate-in valve 2 is referred to as a master cylinder-side pipeline 111, and the pipeline 11 on the pump suction side of the gate-in valve 2 is referred to as a pump suction-side pipeline 112. Details of the gate-in valves 2P and 2S will be described later. A pressure sensor PMC that detects the pressure of the master cylinder M / C is provided between the master cylinder M / C and the gate-in valve 2P.

  The discharge side of each pump P and the master cylinder M / C are connected by pipelines 13P and 13S (hereinafter referred to as pipeline 13 (corresponding to a discharge oil passage)). Further, the discharge side of each pump P and each wheel cylinder W / C are connected by pipes 12P and 12S branched from the pipe 13 (hereinafter referred to as pipe 12 (corresponding to the first oil path)). ing. On each pipeline 12, solenoid-in valves 4FL, 4RR, 4FR, 4RL (hereinafter referred to as solenoid-in valves 4), which are normally open solenoid valves corresponding to the respective wheel cylinders W / C, are provided. Further, check valves 7P and 7S (hereinafter referred to as check valves 7) are provided on the pipe lines 13 and between the solenoid-in valves 4 and the pumps P. The brake fluid is allowed to flow in the direction from the pump P toward the solenoid-in valve 4 (or the master cylinder M / C), and the flow in the opposite direction is prohibited.

  Furthermore, each pipeline 12 is provided with pipelines 17FL, 17RR, 17FR, and 17RL (hereinafter referred to as pipeline 17) that bypass each solenoid-in valve 4, and the pipeline 17 includes a check valve 10FL. , 10RR, 10FR, 10RL (hereinafter referred to as check valve 10). Each check valve 10 allows the flow of brake fluid in the direction from the wheel cylinder W / C toward the pump P (or the master cylinder M / C) and prohibits the flow in the opposite direction.

  The pipe 12 and the pipe 13 merge between the pump P and the solenoid-in valve 4. On each pipeline 13, gate-out valves 3 </ b> P and 3 </ b> S (hereinafter referred to as gate-out valves 3) that are normally open solenoid valves are provided. Here, the pipe line 11 is connected to the master cylinder side of the pipe line 13 with respect to the gate-out valve 3. Each pipeline 13 is provided with pipelines 18P and 18S (hereinafter referred to as pipelines 18) that bypass each gate-out valve 3, and the pipeline 18 includes check valves 9P and 9S (hereinafter referred to as pipelines 18). , Described as a check valve 9). Each check valve 9 permits the flow of brake fluid in the direction from the master cylinder M / C side toward the wheel cylinder W / C, and prohibits the flow in the opposite direction.

  On the suction side of the pump P, reservoirs 16P and 16S (hereinafter referred to as the reservoir 16) are provided. The reservoir 16 and the pump P are connected to the pipes 15P and 15S (hereinafter referred to as the pipe 15 (the scraped oil passage). The check valves 8P and 8S (hereinafter referred to as check valves 8) are provided between the reservoir 16 and the pump P. Each check valve 8 is connected to the pump from the reservoir 16. The brake fluid flow in the direction toward P is allowed and the flow in the opposite direction is prohibited.Foil cylinder W / C and pipe line 15 are pipe lines 14P and 14S (hereinafter referred to as pipe line 14 (reduced pressure oil path). And the pipeline 14 and the pipeline 15 merge between the check valve 8 and the reservoir 16. Each pipeline 14 has a so-called solenoid valve, which is a normally closed solenoid valve. Isoprenoid-out valves 5FL, 5RR, 5FR, 5RL is provided.

  The hydraulic unit 31 receives a brake fluid between the master cylinder M / C and the master cylinder port MPT to which the brake fluid is supplied / refluxed between the P system and the S system, and between the hydraulic unit 31 and each wheel cylinder. A wheel cylinder port WPT to be supplied / refluxed is provided, and a brake pipe formed of a steel pipe or the like is connected thereto.

  The control unit CU is equipped with anti-lock brake control (hereinafter referred to as ABS control), vehicle behavior control (hereinafter referred to as VDC) based on braking commands via wheel speed sensors, yaw rate sensors and longitudinal acceleration sensors or communication lines, etc. Control), automatic braking control (hereinafter referred to as ACC control) and the like are appropriately executed. Based on drive signals based on these controls, drive command values are appropriately output to the motor M and various solenoid valves (gate-out valve 3, solenoid-in valve 4, solenoid-out valve 5). In the first embodiment, the gate-out valve 3 is a proportional solenoid valve whose opening degree can be adjusted, and the other solenoid valves are on-off type solenoid valves. However, all of them may be proportional solenoid valves or all on-off type solenoid valves. There is no particular limitation. Further, the control of the motor M employs the rotational speed control, but it may be simply on / off control. In the first embodiment, the action of increasing the wheel cylinder pressure by the operation of the pump P regardless of the master cylinder pressure or in addition to the master cylinder pressure is referred to as pump-up.

[About the gate-in valve]
(Configuration of gate-in valve)
Next, the gate-in valve 2 will be described. FIG. 2 is a schematic diagram showing the configuration of the gate-in valve 2. 2A shows a state where the ball 81 has moved upward, and FIG. 2B shows a state where the ball 81 is seated.

  The housing 86 includes a ball housing portion 860 that houses the ball 81 and performs a valve function, and a piston housing portion 861 that houses a disk-shaped piston 83 and performs a brake fluid storage function. A through hole 87 is formed above the ball housing portion 860, and the master cylinder side pipe line 111 is connected thereto. A hollow portion 86a1 that is cylindrical and can move the ball 81 within a predetermined range is formed on the inner periphery of the ball receiving portion 860, and a seat surface 86a that is formed in a mortar shape is formed toward the lower surface. . As shown in FIG. 2B, the seat surface 86a is formed so as to obtain an effective pressure receiving area S2 when the ball 81 is seated. The effective pressure receiving area S2 is a circular area, and the diameter of the circle is R.

  A cylindrical passage 86b having a smaller diameter than the ball 81 and a smaller diameter than the above-described diameter R is formed at a substantially central portion of the seat surface 86a. As a result, the hollow portion 80a1 communicates with the inside of the piston housing portion 861. Further, a radial through hole 88 is formed in the ball housing portion 860 so as to penetrate from the middle of the cylindrical passage 86b in the radial direction, and the conduit 112 is connected thereto.

  The piston housing portion 861 is a cylindrical cylinder. The top surface 86c is in contact with the piston 83 when the brake fluid is at atmospheric pressure, and the cylindrical passage 86b is opened. The cylindrical wall 86d has the same diameter as the top surface 86c. And a lower surface 86e that closes the cylindrical wall 86d and has an air release hole (not shown). A seal 84 is attached to the outer periphery of the piston 83. When the brake fluid flows into the piston housing portion 861, the piston 83 is moved to the lower surface side, thereby forming a storage chamber 89 for storing the brake fluid. At this time, the lower surface 86e side of the piston 83 is always at atmospheric pressure by the air release hole. Further, a spring 85 that urges the piston 83 upward in the drawing is accommodated between the piston 83 and the lower surface 86e. When the brake fluid is at atmospheric pressure, the piston 83 is pushed up by the spring 85 to a position where it comes into contact with the upper surface 86c. That is, a predetermined set load is applied to the spring 85.

  A pin 82 is attached to the piston 83. The pin 82 is inserted into the cylindrical passage 82b and has a cylindrical shape with a diameter smaller than the diameter of the cylindrical passage 82b. That is, a passage is formed by a gap formed between the inner periphery of the cylindrical passage 82b and the outer periphery of the pin 82. The piston 83 and the pin 82 are fixed by welding or the like so as to move integrally. In addition, it may be formed by shaving from an integral part, and is not particularly limited.

(Operation of gate-in valve)
Next, the operation of the gate-in valve 2 will be described. In order to explain the characteristic operation of the gate-in valve 2, the state in which the brake pedal BP is not depressed is an initial state, and then the brake pedal BP is depressed and the master cylinder pressure is applied. A description will be given in the order of the state in which the brake fluid is sucked from the master cylinder side by up. Hereinafter, the master cylinder pressure is Pm, the effective pressure receiving area of the piston 83 is S1, the effective pressure receiving area acting on the ball 81 when the ball 81 is seated on the seat surface 86a is S2 (<S1), and the set load of the spring 85 is f1. And Although the set load f1 slightly changes (becomes large) strictly due to the contraction of the spring, it is a very slight change, so it will be described as being substantially constant.

(Step 1: Start master cylinder pressure action from the initial state)
FIG. 2A is a schematic diagram showing the gate-in valve 2 in an initial state where the master cylinder pressure is not acting. When the master cylinder pressure is generated in this state, the ball 81 is not seated on the seat surface 86a, and the hollow portion 86a1 and the storage chamber 89 communicate with each other via the cylindrical passage 86b. A pressure F acts to generate a force F = Pm × S1 that pushes the piston 83 downward. When the master cylinder pressure Pm is low, since the force F is smaller than the set load f1 of the spring 85, the hollow portion 86a1, the pump suction side pipe 112, and the storage chamber 89 are all in communication. Since the check valve 8 is provided between the reservoir 16 and the brake fluid, the brake fluid does not flow to the reservoir 16 side.

(Step 2: Push down the piston by increasing the master cylinder pressure)
When the master cylinder pressure Pm rises and force F> f1, the piston 83 moves downward. Along with this, the pin 82 also moves downward, and the ball 81 also moves downward. This relationship is expressed as follows.
f1 <Pm × S1

(Step 3: Block with ball)
When the ball 81 comes into contact with the seat surface 86a, the state shown in FIG. 2B is established, and the master cylinder side pipe 111 and the pump suction side pipe 112 are blocked. At this time, the pressure acting before and after the ball 81 is
Master cylinder side of ball 81: Pm
Pump suction side of ball 81 (when seated): Ps0 = f1 / S1
It is. If the master cylinder pressure when the ball 81 is seated on the seat surface 86a is Pm0, Pm0 × S1> f1, and therefore, S1> f1 / Pm0 is obtained by deformation. When this is substituted into the above relationship, Ps0 <Pm0 because Ps0 = f1 / S1. Accordingly, the pressure Ps0 on the pump suction side does not become higher than f1 / S1 by being blocked by the ball 81, and is kept below the master cylinder pressure Pm0 at the time of sitting.

(Step 4: Pump operation)
Here, when the pump P is operated, the brake fluid is sucked from the pump suction side pipe 112, and therefore the pressure Ps on the pump suction side is lower than Ps0. When Ps decreases, the force that pushes down the piston 83 decreases. Therefore,
f1- (Ps × S1)> Pm × S2 (pressing force acting on the ball 81)
Then, the ball 81 moves upward, moves away from the seat surface 86a, and the master cylinder side pipe line 111 and the pump suction side pipe line 112 communicate with each other (the pressure Ps on the pump suction side at this time reaches the third predetermined value). means). Therefore, the pump P sucks brake fluid from the master cylinder M / C. Since Ps immediately becomes 0 by the operation of the pump P, the above relational expression is expressed as follows.
f1> Pm × S2

[Technical issues in comparative examples]
Hereinafter, technical problems in the comparative example will be described. FIG. 3 is a schematic diagram showing the configuration of the internal reservoir described in Patent Document 1. The internal reservoir is composed of a ball, a pin, a piston, and a spring, and has a function of regulating the pressure applied from the master cylinder to the pump suction side in addition to storing brake fluid that has flowed out from the pressure reducing control valve. The pressure receiving area of the piston is S1, the effective pressure receiving area of the ball is S2, and the spring force is F1. The brake device described in Patent Document 1 is attractive in that it has a role of a reservoir and a role of a gate-in valve at the same time. Further, the mechanical opening / closing operation according to the hydraulic pressure balance is attractive from the point that no special control is required. However, in order to establish an operation even for a high master cylinder pressure, it is necessary to set the spring force provided in the reservoir large or to set the ball pressure receiving area small. Details will be described below.

  FIG. 4 is a characteristic diagram showing the relationship between hydraulic pressure and spring force (load). As shown in the characteristic diagram, when the spring force is set large, the hydraulic pressure Pr of the brake fluid flowing out from the pressure reducing control valve increases because S1 is fixed. This means that the brake fluid pressure that can be reduced from the wheel cylinder is increased, and the pressure reduction performance on the low μ road surface cannot be obtained. On the other hand, if the pressure receiving area of the ball is set to be small, the suction resistance when sucking in brake fluid from the master cylinder side by pumping up like an automatic brake is increased even if the pressure reduction performance on the low μ road surface can be secured. However, the boosting performance is degraded. Further, when the spring force is set small, the hydraulic pressure Pr of the brake fluid flowing out from the pressure reducing control valve can be reduced as shown by the spring force F1 ′ in FIG. However, there is a problem that the pressure regulation function can be established only to a low master cylinder pressure at the same time, and as a result, the establishment range of the master cylinder pressure becomes narrow. That is, it is effective to increase the spring force in order to widen the master cylinder pressure establishment range, but it is impossible to establish the brake fluid pressure Pr flowing out from the pressure reduction control valve at a low value.

  Therefore, in the first embodiment, the brake fluid flowing out from the pressure reducing control valve is absorbed by the reservoir 16 while constituting a valve specialized for the function of sucking the brake fluid from the master cylinder side when the pump is operated. Thereby, the spring force of the gate-in valve 2 of the first embodiment is set high so that the master cylinder pressure establishment range is widened (meaning that the master cylinder pressure Pm is between the first predetermined value and the second predetermined value). ) The spring force of the reservoir 16 can be set to a spring force that can absorb a lower brake fluid pressure. Thereby, the cylindrical passage 86b of the gate-in valve 2 can be widened so that the effective pressure receiving area of the ball 81 can be set wide, and the suction resistance of the pump can be suppressed. Further, since the spring force of the reservoir 16 can be set independently low, the pressure reduction performance on the low μ road surface can be enhanced. Moreover, the pressure on the pump suction side can be set relatively low, and deterioration of durability due to excessive hydraulic pressure acting on the pump seal member or the like can be avoided.

[Pump up when master cylinder pressure is applied]
Next, the pump-up operation when the master cylinder pressure is applied in the configuration of the first embodiment will be described. FIG. 5 is a time chart showing the pump-up operation of the first embodiment. At time t51, the driver depresses the brake pedal BP, and both the master cylinder pressure Pm and the wheel cylinder pressure Pw increase. When f1 <Pm × S1 at time t52, the gate-in valve 2 is closed, and the pressure Ps0 on the pump suction side does not increase any more.

  When a command signal for increasing the wheel cylinder pressure is output at time t53, the gate-out valve 3 is closed and the motor M is turned on. Since the pressure Ps on the pump suction side is equal to or higher than the third predetermined value, the gate-in valve 2 remains closed, and the pump P sucks the brake fluid in the storage chamber 89. When the pressure Ps on the pump suction side becomes less than the third predetermined value at time t54, the gate-in valve 2 is opened, and brake fluid is sucked from the master cylinder side to increase the pressure of the wheel cylinder.

  When the command signal for increasing the wheel cylinder pressure ends at time t55, the operation of the motor M is turned off. Then, the pressure Ps on the pump suction side starts to increase. At time t56, when the pressure Ps on the pump suction side increases and exceeds the third predetermined value, the gate-in valve 2 is closed again. As a result, the pressure Ps on the pump suction side is kept below the first predetermined value.

  When a control command indicating a pressure reduction request is output at time t57, the gate-out valve 3 is opened, and the wheel cylinder pressure decreases together with the master cylinder pressure Pm that starts to decrease. At time t58, since the master cylinder pressure becomes equal to or lower than the first predetermined value, the gate-in valve 2 is opened, and the pressure Ps on the pump suction side decreases. At time t59, the master cylinder pressure, the wheel cylinder pressure, and the pump suction side pressure all become zero.

  In the first embodiment, the check valve 8 is provided. However, even if the check valve 8 is not provided, the above-described effects can be obtained. However, by using the check valve 8, the master cylinder pressure is transmitted into the reservoir 16 until the master cylinder pressure is applied to the gate-in valve 2 and is closed (that is, the master cylinder pressure is equal to or lower than the first predetermined value). Can reduce the amount of brake fluid that is supplied from the master cylinder, reducing the brake pedal stroke, and improving the response when the wheel cylinder pressure rises during service braking. .

As described above, the effects listed below can be obtained in the first embodiment.
(1) Pipe line 11 (suction oil path) connecting the master cylinder M / C and the suction side of the rotary pump P, and pipe line 13 (discharge oil path) connecting the discharge side of the rotary pump P and the master cylinder M / C ), A pipe 12 that branches off from the pipe 13 and communicates with the wheel cylinder (first oil path), and a pipe 14 that communicates with the reservoir 16 that stores brake fluid decompressed from the wheel cylinder (depressurized oil path). And a pipe 15 (scraping oil path) communicating the reservoir 16 and the pipe 11 (suction oil path), and opening and closing the pipe 11 (suction oil path) in relation to the master cylinder pressure and the pressure on the pump suction side. And a gate-in valve 2 (gate-in valve) that performs the operation. That is, since the gate-in valve 2 that opens and closes in relation to the pressure is provided in addition to the reservoir 16, the characteristics of the gate-in valve can be easily set.

  (2) The gate-in valve 2 opens and closes according to the master cylinder pressure before and after the gate-in valve 2 in the pipe line 13 (suction passage) and the pressure difference on the pump suction side. Thus, since it operates by the longitudinal pressure, it can be easily opened and closed.

  (3) The gate-in valve 2 closes when the master cylinder pressure is not less than the first predetermined value and not more than the second predetermined value, and the pressure on the pump suction side is not less than the third predetermined value. The valve is opened below. In other words, the operating pressure of the gate-in valve 2 can be arbitrarily set, the pump can be sucked when the master cylinder pressure is applied, and the low pressure portion of the pump can be protected.

  (4) A check valve 8 is provided in the conduit 15 (scraping oil passage) to block the flow from the gate-in valve 2 toward the reservoir 16 and allow the flow in the reverse direction. Therefore, it is possible to prevent the brake fluid from flowing into the reservoir 16 when the master cylinder pressure is applied, and to suppress deterioration of the pedal feeling.

  (5) The gate-in valve 2 is linked to a ball 81 (ball valve) seated on a valve seat formed in a part of the pipe line 13 (suction passage) that is closed by pressure from the master cylinder, and the ball 81 The piston 83 that operates in this manner, and a spring 85 (spring member) that presses the piston 83 toward the ball 81 side. Therefore, the gate-in valve 2 can be configured with a simple structure.

  (6) When the master cylinder pressure is Pm, the cross-sectional area of the piston 83 is S1, the cross-sectional area of the suction passage where the ball 81 is closed is S2, and the spring force of the spring 85 is f1, the spring force f1 is Pm × S1> It is set by f1> Pm × S2. Since the performance as the reservoir 16 is not affected, the spring force corresponding to the master cylinder pressure in a wide range can be easily set.

  (7) The first predetermined value is set to f1 / S1, the second predetermined value is set to f1 / S2, and the third predetermined value is set to 0 <first predetermined value. Therefore, the gate-in valve 2 can be easily set according to the requested conditions.

  (8) A rotary pump P that is rotated by the rotational movement of the motor, and a hydraulic unit 31 (housing) that incorporates the rotary pump and an oil passage includes a master cylinder port that connects the oil passage with an external master cylinder M / C. MPT, pipe 11 (suction oil path) connecting the master cylinder port MPT and the suction side of the rotary pump P as an oil path, and the discharge side of the rotary pump P and the master cylinder port MPT branched from the pipe 11 A wheel cylinder port WPT that communicates a conduit 13 (discharge passage) that communicates, a conduit 12 (first passage) that branches off from the conduit 13, and an external wheel cylinder, and a wheel cylinder that passes through the wheel cylinder port WPT. The reservoir 14 into which the brake fluid flows is formed, and a conduit 14 (reduced pressure oil passage) that communicates with the reservoir 16 and a conduit 15 (scraping oil passage) that communicates between the reservoir 16 and the conduit 11 (suction oil passage) are formed. , With a gate-in valve 2 to open and close operation at the differential pressure in the conduit 11 (intake oil passage) (differential pressure regulating valve). That is, since the gate-in valve 2 that opens and closes in relation to the pressure is provided in addition to the reservoir 16, the characteristics of the gate-in valve can be easily set.

  (9) A hydraulic unit 31 (housing) having a rotary pump P and an oil passage formed therein, a conduit 11 (suction oil passage) connecting the outside of the hydraulic unit 31 and the suction side of the rotary pump P, and a rotary type A conduit 13 (discharge oil passage) connecting the discharge side of the pump P and the outside of the hydraulic unit 31, a conduit 12 (first oil passage) branched from the conduit 13 and communicating with the wheel cylinder, and outside the hydraulic unit 31 An opening / closing operation is provided according to the differential pressure before and after the pipe 14 (reduced pressure oil path) communicating with the reservoir 16 storing the brake fluid flowing from the provided wheel cylinder and the pipe 11 (suction oil path). The rotary pump P sucks brake fluid from the outside of the hydraulic unit 31 via the gate-in valve 2. That is, since the gate-in valve 2 that opens and closes in relation to the pressure is provided in addition to the reservoir 16, the characteristics of the gate-in valve can be easily set.

  Next, Example 2 will be described. Since the basic configuration is the same as that of the first embodiment, only different points will be described. FIG. 6 is a hydraulic circuit diagram of a brake system to which the brake device of the second embodiment is applied. In the first embodiment, the check valve 8 is provided on the pipe line 15 to improve the pedal feeling. In contrast, in the second embodiment, the check valve 8 is removed, and electromagnetic open / close valves 80S and 80P (hereinafter, electromagnetic open / close valve 80) are provided on the pipe line 11 between the gate-in valve 2 and the pipe line 15. Is different. The electromagnetic open / close valve 80 is opened / closed by a command current from the control unit CU to communicate / block the gate-in valve 2 and the pump suction side pipe line 15.

  Next, the operation will be described. During normal braking, the electromagnetic on-off valve 80 is closed. When the wheel cylinder pressure is controlled to be higher than the master cylinder pressure, such as brake assist control, the electromagnetic on-off valve 80 is opened when the pump P is operated. Therefore, during normal braking, consumption of brake fluid in the pipeline 11 is suppressed until the master cylinder pressure is applied to the gate-in valve 2 and closed (that is, the master cylinder pressure is equal to or lower than the first predetermined value). Thus, it is possible to prevent the reservoir 16 and the solenoid out valve 5 from acting, and to prevent the reservoir 16 and the solenoid out valve 5 from acting on the pump suction side. As a result, the amount of brake fluid consumed from the master cylinder M / C can be further reduced, the brake pedal stroke can be shortened, and the wheel cylinder pressure rising response during normal braking can be improved. In addition, when the wheel cylinder pressure is controlled to be higher than the master cylinder pressure, the same effects as in the first embodiment can be obtained while the electromagnetic on-off valve 80 is opened. Further, for example, when the brake fluid stored in the reservoir 16 is scraped out when the master cylinder pressure is substantially 0, that is, when the gate-in valve 2 is open, the master cylinder M / C Therefore, the pump P can be prevented from inhaling the brake fluid from the internal reservoir 16, and the brake fluid in the internal reservoir 16 can be scraped out efficiently.

As described above, in the second embodiment, the following operational effects can be obtained in addition to the operational effects of the first embodiment.
(10) Since the solenoid valve 80 is provided between the gate-in valve 2 and the pump P in the pipeline 11 (suction passage), the brake pedal stroke is shortened and the wheel cylinder pressure rise response during normal braking Can be improved. Further, the brake fluid stored in the reservoir 16 can be scraped out efficiently.

  Next, Example 3 will be described. Since the basic configuration is the same as that of the first embodiment, only different points will be described. FIG. 7 is a hydraulic circuit diagram of a brake system to which the brake device of the third embodiment is applied. In the first embodiment, the check valve 8 is provided on the pipe line 15 to improve the pedal feeling. On the other hand, the third embodiment is different in that, instead of the check valve 8, electromagnetic open / close valves 800S and 81P (hereinafter, electromagnetic open / close valve 800) are provided in the pipe line 15. The electromagnetic open / close valve 800 is opened / closed by a command current from the control unit CU, and communicates / blocks between the gate-in valve 2 and the pump suction side pipe line 15.

  Next, the operation will be described. Only when the brake fluid stored in the reservoir 16 is scraped out by ABS control or the like, the electromagnetic on-off valve 800 is opened, and other than that (in normal braking, the wheel cylinder pressure is higher than the master cylinder pressure). Is closed). Therefore, by opening the brake fluid stored in the reservoir 16 by ABS control or the like, it is possible to obtain the same effect as that of the first embodiment. Further, during normal braking, the brake fluid acts on the reservoir 16 and the solenoid-out valve 5 until the master cylinder pressure is applied to the gate-in valve 2 and is closed (that is, the master cylinder pressure is equal to or lower than the first predetermined value). Can be prevented. Thereby, the consumption of the brake fluid supplied from the master cylinder M / C can be reduced. In addition, when the wheel cylinder pressure is controlled to be higher than the master cylinder pressure, the electromagnetic on-off valve 800 is closed, so that the brake fluid sucked by the pump P can be sucked only from the master cylinder side. Therefore, the control performance (control accuracy) in the pressure increase control can be improved.

As described above, in the third embodiment, the following operational effects can be obtained in addition to the operational effects of the first embodiment.
(11) Since the electromagnetic opening / closing valve 800 is provided between the gate-in valve 2 and the reservoir 16 in the pipe line 15 (scraping passage), the stroke of the brake pedal is shortened, and the rising response of the wheel cylinder pressure during normal braking Can be improved. Further, the brake fluid stored in the reservoir 16 can be scraped out efficiently. Moreover, the control performance at the time of pressure increase control can be improved.

1 Input rod 2 Gate-in valve (gate-in valve, differential pressure valve)
3 Gate-out valve 4 Solenoid in valve 5 Solenoid out valve 7 Check valve 8 Check valve 9 Check valve 10 Check valve 11 Pipe line (suction oil path)
12 pipeline (first oil passage)
13 Pipeline (Discharge oil passage)
14 pipeline (depressurized oil passage)
15 pipeline (scraping oil passage)
16 Reservoir 31 Hydraulic unit (housing)
80 Electromagnetic on-off valve 800 Electromagnetic on-off valve 81 Ball 82 Pin 82b Cylindrical passage 83 Piston
CU control unit
MPT Master cylinder port P Pump
W / C wheel cylinder
WPT wheel cylinder port

Claims (2)

A suction oil passage connecting the master cylinder and the suction side of the rotary pump;
A discharge oil passage connecting the discharge side of the rotary pump and the master cylinder;
A first oil passage branched from the discharge oil passage and communicating with the wheel cylinder;
A decompression oil passage communicating with a reservoir for storing brake fluid decompressed from the wheel cylinder;
A scraped oil passage communicating the reservoir and the suction oil passage;
A gate-in valve that is provided in the suction oil passage and closes when the master cylinder pressure acts, and that opens and closes the suction oil passage when the master cylinder pressure acts and the pump is rotating;
With
The pump device sucks brake fluid through the gate-in valve performing the opening / closing operation when the master cylinder pressure is applied. A rotary pump that rotates by the rotational movement of the motor;
A housing incorporating the rotary pump and an oil passage;
The housing includes a master cylinder port that connects an external master cylinder and the oil passage;
A suction oil passage connecting the master cylinder port and the suction side of the rotary pump as the oil passage;
A discharge passage branched from the intake oil passage and communicating between the discharge side of the rotary pump and the master cylinder port;
A wheel cylinder port that communicates the first passage branched from the discharge passage and an external wheel cylinder; and a pressure reducing oil passage that communicates a reservoir through which the brake fluid flows in the wheel cylinder through the wheel cylinder port;
A scraped oil passage communicating the reservoir and the suction oil passage;
Form the
The suction oil passage is provided with a differential pressure valve that opens and closes according to the differential pressure across it, and the differential pressure valve is set to open and close when the master cylinder pressure acts and the rotary pump rotates, and the rotary pump Is set to suck the brake fluid through the differential pressure valve.

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