JP7123139B2 - Hydraulic control unit for vehicle braking system - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control unit for a vehicle brake system, and more particularly to a hydraulic control unit having a pump for increasing the hydraulic pressure of brake fluid.

A conventional brake system for a vehicle includes a main flow path that communicates a master cylinder and a wheel cylinder, a sub-flow path that releases the brake fluid in the main flow path, and a supply flow path that supplies the brake fluid to the middle of the sub-flow path. , with hydraulic circuits.

For example, the upstream end of the flow of the brake fluid in the sub-flow path is connected to the wheel cylinder side region of the main flow path based on the inlet valve, and the downstream end of the sub-flow path is: It is connected to a region of the main flow path on the master cylinder side with respect to the inlet valve. Further, the upstream end of the supply channel in the flow of the brake fluid communicates with the master cylinder, and the downstream end of the supply channel is the downstream side of the sub-channel with reference to the loosening valve. area and is connected to the suction side of a pump located in that area. In addition, a first switching valve is provided in a region of the main flow path on the master cylinder side based on a connection portion with a downstream end of the sub flow path, and a second switching valve is provided in the middle of the supply flow path. A switching valve is provided.

For example, a fluid pressure control unit is composed of a charging valve, a releasing valve, a pump, a first switching valve, a second switching valve, a housing in which they are incorporated, and a controller that controls their operations. In the hydraulic pressure control unit, the hydraulic pressure in the hydraulic circuit is controlled by controlling the operations of the fill valve, the release valve, the pump, the first switching valve, and the second switching valve.

In particular, when it becomes necessary to increase the hydraulic pressure of the brake fluid in the wheel cylinder, the fill valve opens and the release valve opens, regardless of the state of brake operation at the brake system input (for example, the brake pedal). closed, the first switching valve is closed, and the second switching valve is open, the pump is driven.

When the pump is driven, the pulsation generated in the brake fluid is transmitted from the brake system to the engine compartment of the vehicle, which may generate noise. This noise can be so loud that the user (driver) feels uncomfortable. For this reason, some conventional hydraulic control units for brake systems have been proposed to reduce the pulsation that occurs when the pump is driven. For example, the hydraulic pressure control unit of the brake system described in Patent Document 1 includes one pump in one hydraulic circuit, and reduces the pulsation of the brake fluid discharged from the pump on the discharge side of the pump. Equipped with a pulsation reduction device.

JP 2013-241149 A

However, the pulsation reducing device described in Patent Document 1 has a first orifice through which the brake fluid discharged from the pump passes, and a second orifice through which the brake fluid passes when the flow rate of the discharged brake fluid exceeds a predetermined flow rate. However, since the structure is provided in parallel with the first orifice, the inner diameter of the flow path near the discharge port of the pump must be made larger than the inner diameter of the discharge flow path, and additional costs are incurred for processing the flow path. . In addition, a stepped portion is provided in the flow path for holding the pulsation reducing device having the orifice structure in the flow path, which similarly requires additional flow path processing.

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned problems. It is an object of the present invention to provide a brake device having a throttle member capable of adjusting the degree of pulsation reduction accordingly.

A hydraulic control unit for a vehicle brake system according to the present invention includes:
A hydraulic pressure control unit for a vehicle brake system comprising a discharge passage (140) through which brake fluid pressurized by a pump is discharged, and a throttle member (80) in the middle of the discharge passage (140), wherein: The throttle member (80) partitions the sleeve-shaped base (81 ) into an inflow chamber (83) into which the brake fluid flows and an outflow chamber (84) into which the brake fluid flows out. and a partition member (82), wherein the partition member (82) has a fixed portion (82a) fixed to the base ( 81) and a non-fixed portion (82b) not fixed to the base (81). , and the base body (81) has a stopper (86) abutting against the non-fixed portion (82b) from the inflow chamber (83) side .

Since the brake device according to the present invention employs a throttle member having a sleeve-shaped base body, it is possible to design the throttle member in accordance with the inner diameter of the discharge pipe of the pump, thereby avoiding unnecessary addition of the discharge passage. No processing required. Further, according to the present invention, since the partition for absorbing the pulsation is arranged between the inflow chamber and the outflow chamber, it is possible to easily design a connecting structure for connecting the throttle members.

It is a figure showing an example of system composition of a brake system concerning an embodiment of the invention. FIG. 4 is a partial cross-sectional view showing an example of a state in which the pump and throttle member are mounted on the housing in the hydraulic pressure control unit of the brake system according to the embodiment of the present invention; FIG. 4 is a cross-sectional view of an embodiment of a throttle member in the hydraulic pressure control unit of the brake system according to the embodiment of the present invention; FIG. 4 is a cross-sectional view of an embodiment of a throttle member in the hydraulic pressure control unit of the brake system according to the embodiment of the present invention;

A hydraulic control unit according to the present invention will be described below with reference to the drawings.
In the following description, the brake system including the hydraulic pressure control unit according to the present invention is installed in a four-wheeled vehicle. It may be mounted on vehicles other than wheeled vehicles (motorcycles, trucks, buses, etc.). Also, the configuration, operation, and the like described below are merely examples, and the brake system including the hydraulic control unit according to the present invention is not limited to such configuration, operation, and the like. Moreover, in each figure, the same or similar members or parts are given the same reference numerals, or the reference numerals are omitted. In addition, detailed structures are simplified or omitted as appropriate.

<Configuration and Operation of Brake System 1>
The configuration and operation of the brake system 1 according to this embodiment will be described.
FIG. 1 is a diagram showing an example system configuration of a brake system according to an embodiment of the present invention.

As shown in FIG. 1, the brake system 1 is mounted on a vehicle 100, and includes a main flow path 13 that communicates a master cylinder 11 and a wheel cylinder 12, a sub-flow path 14 that releases the brake fluid in the main flow path 13, and a sub-flow path 14 that releases the brake fluid in the main flow path 13. It includes a hydraulic circuit 2 having a supply channel 15 for supplying brake fluid to the channel 14 . The hydraulic circuit 2 is filled with brake fluid. The brake system 1 according to this embodiment includes two hydraulic circuits 2 a and 2 b as the hydraulic circuit 2 . The hydraulic circuit 2 a is a hydraulic circuit that communicates the master cylinder 11 with the wheel cylinders 12 of the wheels RL and FR via the main flow path 13 . The hydraulic circuit 2b is a hydraulic circuit that communicates the master cylinder 11 with the wheel cylinders 12 of the wheels FL and RR via the main flow path 13 . These hydraulic circuits 2a and 2b have the same configuration except that the wheel cylinders 12 that communicate with them are different.

The master cylinder 11 incorporates a piston (not shown) that reciprocates in conjunction with a brake pedal 16 that is an example of an input portion of the brake system 1 . A booster 17 is interposed between the brake pedal 16 and the piston of the master cylinder 11, and the pedaling force of the user is boosted and transmitted to the piston. The wheel cylinder 12 is provided on the brake caliper 18 . When the hydraulic pressure of the brake fluid in the wheel cylinder 12 increases, the brake pad 19 of the brake caliper 18 is pressed against the rotor 20 to brake the wheel.

The upstream end of the sub-channel 14 is connected to the midway portion 13 a of the main channel 13 , and the downstream end of the sub-channel 14 is connected to the mid-way portion 13 b of the main channel 13 . The upstream end of the supply channel 15 communicates with the master cylinder 11 , and the downstream end of the supply channel 15 is connected to the middle portion 14 a of the sub-channel 14 .
The upstream side of the sub-flow path 14 means the upstream side in the flow of the brake fluid when the pump is driven and the brake fluid is returned from the wheel cylinder to the master cylinder, and the downstream side means the brake. Refers to the downstream side of the liquid flow.

An inlet valve (EV) 31 is provided in a region of the main flow passage 13 between the middle portion 13b and the middle portion 13a (the region on the wheel cylinder 12 side with respect to the middle portion 13b). A release valve (AV) 32 is provided in a region between the upstream end portion and the middle portion 14a of the sub-channel 14 . An accumulator 33 is provided in a region of the secondary flow path 14 between the release valve 32 and the intermediate portion 14a. The inlet valve 31 is, for example, an electromagnetic valve that opens in a non-energized state and closes in an energized state. The loosening valve 32 is, for example, an electromagnetic valve that closes in a non-energized state and opens in an energized state.

A pump 60 is provided in a region between the intermediate portion 14a and the downstream end portion of the sub-channel 14 . The suction side of the pump 60 communicates with the intermediate portion 14a. The discharge side of the pump 60 communicates with the downstream end of the sub-channel 14 . Specifically, the brake system 1 includes a suction flow path 142 and a discharge flow path 140 that are part of the sub-flow path 14 as components of the hydraulic pressure control unit 50 . The suction flow path 142 forms a flow path between the upstream end of the sub-flow path 14 and the suction side of the pump 60 , and the discharge flow path 140 forms a flow path between the discharge side of the pump 60 and the downstream side of the sub-flow path 14 . It constitutes a flow path between the ends.

Here, the hydraulic pressure control unit 50 includes a throttle member 80 that dampens the pulsation of the brake fluid discharged from the pump 60 onto the discharge flow path. More specifically, the pump 60 is arranged in the discharge passage 140 so that the discharge side of the pump 60 faces the inflow chamber 83 into which the brake fluid of the throttle member 80 flows.

A first switching valve (USV) 35 is provided in a region of the main flow path 13 on the master cylinder 11 side with respect to the midway portion 13b. A second switching valve (HSV) 36 and a damper unit 37 are provided in the supply flow path 15 . The damper unit 37 is provided in a region of the supply flow path 15 between the second switching valve 36 and the downstream end. The first switching valve 35 is, for example, an electromagnetic valve that opens in a non-energized state and closes in an energized state. The second switching valve 36 is, for example, an electromagnetic valve that closes in a non-energized state and opens in an energized state. It should be noted that the damper unit 37 can be operated without the damper unit 37, depending on the installation space and required pulsation damping characteristics.

At least the housing 51 , each member provided in the housing 51 , and the controller (ECU) 52 constitute the fluid pressure control unit 50 . In the hydraulic pressure control unit 50, the operation of the charging valve 31, the releasing valve 32, the pump 60, the first switching valve 35, and the second switching valve 36 is controlled by the controller 52, so that the brake fluid in the wheel cylinder 12 is is controlled. That is, the controller 52 controls the operations of the charging valve 31 , the releasing valve 32 , the pump 60 , the first switching valve 35 and the second switching valve 36 .

The number of controllers 52 may be one, or may be divided into a plurality. Also, the controller 52 may be attached to the housing 51 or may be attached to another member. Further, part or all of the controller 52 may be composed of, for example, a microcomputer, a microprocessor unit, or the like, or may be composed of an updatable device such as firmware, or may be composed of a command from a CPU or the like. It may be a program module or the like executed by.

The controller 52 performs, for example, the following hydraulic pressure control actions in addition to well-known hydraulic pressure control actions (ABS control action, ESP control action, etc.).
When the brake pedal 16 of the vehicle 100 is operated with the loading valve 31 open, the release valve 32 closed, the first switching valve 35 open, and the second switching valve 36 closed. When the lack or possibility of shortage of the hydraulic pressure in the hydraulic circuit 2 is detected from the detection signal of the position sensor of the brake pedal 16 and the detection signal of the hydraulic pressure sensor of the hydraulic circuit 2, the controller 52 Start the active boost control operation.

In the active pressure increase control operation, the controller 52 allows the brake fluid to flow from the middle portion 13b of the main flow path 13 to the wheel cylinder 12 by keeping the inlet valve 31 open. Controller 52 also limits the flow of brake fluid from wheel cylinder 12 to accumulator 33 by keeping release valve 32 closed. Further, the controller 52 closes the first switching valve 35 to restrict the flow of the brake fluid in the flow path from the master cylinder 11 to the intermediate portion 13 b of the main flow path 13 without the pump 60 . Further, the controller 52 opens the second switching valve 36 to allow the flow of the brake fluid in the flow path from the master cylinder 11 to the intermediate portion 13 b of the main flow path 13 via the pump 60 . The controller 52 also drives the pump 60 to increase (increase) the hydraulic pressure of the brake fluid in the wheel cylinder 12 .

When it is detected that the shortage of hydraulic pressure in the hydraulic circuit 2 has been eliminated or avoided, the controller 52 opens the first switching valve 35, closes the second switching valve 36, and stops driving the pump 60. By doing so, the active pressure increase control operation ends.

Here, when the pump 60 is driven, the pulsation generated in the brake fluid may be transmitted to the wheel cylinder 12 through the secondary flow path 14 and the main flow path 13 . This pulsation is also transmitted to the engine room in which the hydraulic pressure control unit 50 of the brake system 1 is accommodated, and noise may be generated. This noise can be so loud that the user (driver) feels uncomfortable. Therefore, it is important to reduce the pulsation that occurs when the pump 60 is driven.

Therefore, in the brake system 1 according to the present embodiment, that is, the hydraulic pressure control unit 50 , the brake fluid discharged from the pump 60 flows into the throttle member 80 . The brake fluid that has flowed into the throttle member 80 flows downstream from the throttle member 80 after the pulsation is attenuated in the throttle member 80 . Therefore, the brake system 1 according to the present embodiment, that is, the hydraulic pressure control unit 50 can reduce the pulsation that occurs when the pump 60 is driven.

In the active pressure increase control described above, the user operates (depresses) the brake pedal 16 and the pump 60 is driven with the second switching valve 36 open. Therefore, the pulsation generated in the brake fluid is propagated to the brake pedal 16 via the supply passage 15 and the master cylinder 11, giving the user a sense of discomfort. Therefore, it is preferable that the brake system 1 according to the present embodiment, that is, the hydraulic pressure control unit 50, includes the damper unit 37 as shown in FIG. This is because the damper unit 37 can dampen the pulsation of the brake fluid that propagates from the pump 60 to the brake pedal 16 .

Further, when the damper unit 37 is provided in the brake system 1 in which the booster 17 is omitted, the damper unit 37 is provided between the upstream end of the supply passage 15 and the second switching valve 36. It may be provided in the area. By providing the damper unit 37 at such a position, when the user steps on the brake pedal 16, the brake fluid can flow into the damper unit 37, and the brake fluid in the hydraulic circuit 2 transmitted to the brake pedal 16 can be dissipated. Reaction force is reduced. Therefore, when the user depresses the brake pedal, the amount of depression of the brake pedal 16 similar to that of the brake system 1 having the booster 17 can be obtained. Therefore, the user can obtain the same feeling of use as the brake system 1 provided with the booster 17 in the brake system 1 in which the booster 17 is omitted.

<Mounting Configuration of Pump 60 and Throttle Member 80 on Housing 51>
An example of the configuration when mounting the pump 60 and the throttle member 80 to the housing 51 in the hydraulic pressure control unit 50 of the brake system 1 according to the present embodiment will be described.
FIG. 2 is a partial cross-sectional view showing an example of how the pump and throttle member 80 are mounted on the housing in the hydraulic pressure control unit of the brake system according to the embodiment of the present invention. Note that FIG. 2 shows an example in which one pump 60 is provided in one hydraulic circuit. FIG. 2 also shows a state in which the drive shaft 57 that drives the piston 62 of the pump 60 is removed. Therefore, in FIG. 2, the drive shaft 57 and the eccentric portion 57a formed on the drive shaft 57 are shown by imaginary lines (chain lines).

As shown in FIG. 2, the housing 51 is formed with a housing chamber 59 in which a drive shaft 57 for driving the piston 62 of the pump 60 is provided. The storage chamber 59 is a bottomed hole formed in the outer wall of the housing 51 . Further, the housing 51 is formed with a storage chamber 53 that stores the pump 60 . These storage chambers 53 are stepped through holes penetrating from the outer wall of the housing 51 to the storage chamber 59 .

A pump 60 housed in the housing chamber 53 includes a cylinder 61, a piston 62, and the like. The cylinder 61 is formed in a bottomed cylindrical shape having a bottom portion 61b. One end side of a piston 62 is accommodated in the cylinder 61 . A space surrounded by the inner peripheral surface of the cylinder 61 and the one end of the piston 62 serves as a pump chamber 63 . The piston 62 can reciprocate in the axial direction of the cylinder 61 . An end portion 62 a of the piston 62 on the other end side protrudes into the housing chamber 59 . Furthermore, an annular seal member 66 is attached to the portion of the piston 62 that is housed in the cylinder 61 . This seal member 66 prevents leakage of brake fluid between the outer peripheral surface of the piston 62 and the inner peripheral surface of the cylinder 61 .

A spring 67 is accommodated in the cylinder 61 between the bottom portion 61 b and the piston 62 , that is, in the pump chamber 63 . The spring 67 always urges the piston 62 toward the housing chamber 59 . As a result, the end portion 62 a of the piston 62 is in contact with the eccentric portion 57 a formed on the drive shaft 57 inside the housing chamber 59 . The center position of the eccentric portion 57 a is eccentric with respect to the center of rotation of the drive shaft 57 . Therefore, when the drive shaft 57 is rotated by a drive source (not shown), the eccentric portion 57 a rotates eccentrically with respect to the center of rotation of the drive shaft 57 . That is, the piston 62 whose end portion 62a is in contact with the eccentric portion 57a reciprocates in the axial direction of the cylinder 61 due to the eccentric rotational motion of the eccentric portion 57a.

A portion of the piston 62 protruding from the cylinder 61 is slidably guided by a guide member 68 provided on the inner peripheral surface of the housing chamber 53 . An annular seal member 69 is attached adjacent to the guide member 68 in the housing chamber 53 . This seal member 69 seals the outflow from the outer peripheral surface of the piston 62 in a liquid-tight manner.

The piston 62 is axially formed with a bottomed hole 62 b that opens toward the pump chamber 63 of the cylinder 61 . The piston 62 is also formed with an intake port 62c, which is a through hole that communicates between the outer peripheral surface of the piston 62 and the bottomed hole 62b. In addition, the piston 62 is provided with a suction valve (not shown) for opening and closing the opening of the bottomed hole 62b. The suction valve includes a ball valve that closes the opening of the bottomed hole 62b and a spring that biases the ball valve from the cylinder 61 side. A cylindrical filter 70 is attached to the end of the cylinder 61 on the side of the piston 62 so as to cover the opening of the intake port 62c of the piston 62 .

A bottom portion 61b of the cylinder 61 is formed with a through hole 61c that communicates the pump chamber 63 with the outside of the cylinder 61 . A discharge valve 64 is provided on the opening side of the through hole 61c opposite to the pump chamber 63 . The discharge valve 64 includes a ball valve 64a, a valve seat 64b formed at the periphery of the opening end of the through hole 61c on which the ball valve 64a can be seated and disengaged, and biasing the ball valve 64a in a direction to seat the ball valve 64a on the valve seat 64b. and a spring 64c. This discharge valve 64 is arranged between the cylinder 61 and the cover 65 .

Specifically, the cover 65 is attached to the bottom portion 61b of the cylinder 61 by, for example, press fitting. The cover 65 is formed with a bottomed hole 65a having an opening at a position facing the through hole 61c of the bottom portion 61b. A spring 64c of the discharge valve 64 is accommodated in a bottomed hole 65a. The inner diameter of the bottomed hole 65a is larger than the outer diameter of the ball valve 64a. Therefore, when the ball valve 64a is separated from the valve seat 64b, the ball valve 64a moves into the bottomed hole 65a. That is, when the hydraulic pressure of the brake fluid in the pump chamber 63 of the cylinder 61 increases and the force of the brake fluid pushing the ball valve 64a becomes greater than the urging force of the spring 64c, the ball valve 64a moves from the valve seat 64b. The pump chamber 63 and the bottomed hole 65a of the cover 65 communicate with each other through the through hole 61c. Then, the brake fluid in the pump chamber 63 flows into the bottomed hole 65a. The cover 65 is formed with a groove as a discharge port 65b that communicates the outside of the cover 65 with the bottomed hole 65a. The brake fluid that has flowed into the bottomed hole 65a of the cover 65 is discharged to the outside of the cover 65, that is, the outside of the pump 60 through the discharge port 65b.

The pump 60 configured in this manner is accommodated in the accommodation chamber 53 formed in the housing 51 as described above. Specifically, in a state in which an annular projecting portion 61a formed on the outer peripheral portion of the cylinder 61 is in contact with the stepped portion 53a of the housing chamber 53, the periphery of the opening of the housing chamber 53 is crimped, whereby the pump 60 is is fixed within the receiving chamber 53 of the housing 51 .

When the pump 60 is accommodated in the accommodation chamber 53 in this manner, a discharge chamber 54, which is a space communicating with the discharge port 65b of the pump 60, is formed between the outer peripheral surface of the pump 60 and the inner peripheral surface of the accommodation chamber 53. be done. That is, the discharge chamber 54 is an annular space formed on the outer peripheral side of the pump 60 so as to communicate with the discharge port 65 b of the pump 60 . The discharge chamber 54 constitutes a part of the first discharge flow path 140 as described later.

In the pump 60 , the space between the annular projecting portion 61 a of the cylinder 61 and the cover 65 is partitioned into two spaces by the partition portion 71 . A space on the cover 65 side of the partition portion 71 serves as the discharge chamber 54 . A space on the projecting portion 61 a side of the partition portion 71 serves as an annular flow path 55 .

In the present embodiment, when the pump 60 is housed in the housing chamber 53, a space communicating with the suction port 62c of the pump 60 is provided between the outer peripheral surface of the pump 60 and the inner peripheral surface of the housing chamber 53. An annular channel 56 is formed. That is, the annular flow path 56 is a space annularly formed on the outer peripheral side of the pump 60 so as to communicate with the suction port 62 c of the pump 60 . The annular flow path 56 is formed between the annular protrusion 61 a of the cylinder 61 and the seal member 69 . In other words, the annular flow path 56 is formed on the outer peripheral side of the filter 70 provided so as to cover the opening of the suction port 62c.

The annular channel 56 communicates with the intermediate portion 14a of the sub-channel 14 in FIG. 1 through an internal channel (not shown) formed in the housing 51 . In other words, the annular channel 56 forms part of the secondary channel 14 . When the pump 60 is housed in the housing chamber 53, the suction port 62c of the pump 60 and the midway portion 14a must communicate with each other. By having the annular flow path 56, when the pump 60 is accommodated in the accommodation chamber 53, alignment for communicating the suction port 62c of the pump 60 and the intermediate portion 14a is not required. Therefore, having the annular flow path 56 facilitates assembly of the hydraulic control unit 50 . Moreover, since the annular flow path 56 is provided, when processing the storage chamber 53 into the housing 51, a part of the sub-flow path 14 is also processed. Therefore, the processing cost of the housing 51, that is, the manufacturing cost of the hydraulic control unit 50 can be reduced. Moreover, since the space on the outer peripheral side of the pump 60 can be effectively used as the sub-flow path 14 by having the annular flow path 56, the housing 51, that is, the hydraulic pressure control unit 50 can be made smaller.

Next, the diaphragm member 80 will be described.
The diaphragm member 80 is composed of a sleeve-shaped base body 81 having openings at both ends and a partition member 82 . The throttle member 80 has an inflow chamber 83 into which the brake fluid discharged from the pump 60 flows and an outflow chamber 84 into which the brake fluid flows out.

The outer diameter of the throttle member 80 is substantially uniform over the entire throttle member and is slightly smaller than the inner diameter of the discharge flow path 140 . The inner diameter of the throttle member differs between the inflow chamber 83 and the outflow chamber 84 as follows. In the inflow chamber 83, the inner diameter at the inflow opening 83b of the inflow chamber 83 is set larger than the inner diameter inside the inflow chamber. is provided.

A connecting portion 84a for connecting with another throttle member is provided on the outer peripheral surface of the outflow opening 84b of the outflow chamber 84. As shown in FIG. The connecting portion 84a has a stepped portion 84ab whose diameter is smaller than the outer diameter of the housing and a tapered portion 84ac which tapers toward the outflow opening 84b. The diaphragm members 80 are connected to each other by engaging with the connected portion 83a provided on the inner peripheral surface of the portion 83b.

The throttle member 80 is installed in the discharge flow path 140 by inserting the throttle member 80 from the outside of the housing 51 after forming the discharge flow path 140 in the housing 51 . FIG. 2 shows two diaphragm members 80 arranged in series. This is achieved by connecting the two throttle members 80 in advance before inserting the throttle member 80 into the discharge flow path 140 and then inserting the connected two throttle members 80 into the discharge flow path 140. It is possible to install.

A fixed portion (not shown) may be provided on the base of the throttle member so that the throttle member 80 is immovably fixed in the discharge channel 140 after the throttle member 80 is inserted into the discharge channel 140 .
Specifically, the fixed portion may be a projecting portion provided on the outer peripheral surface of the inflow chamber 83 near the inflow opening 83b.

3a is a diagram showing an embodiment of the partition member 82, FIG. 3b is a diagram of the inside of the throttle member as seen from the outflow chamber side, and FIG. 3c is a diagram of the inside of the throttle member as seen from the inflow chamber side. It is a diagram.

The partition member 82 is formed of a thin metal plate and has a substantially semicircular enlarged diameter portion 82a and a substantially semicircular reduced diameter portion 82b having a smaller radius than the enlarged diameter portion. It has a shape in which the centers of are overlapped and connected. A communication hole 82c for communicating the inflow chamber 83 and the outflow chamber 84 of the throttle member is provided in the region of the reduced diameter portion 82b.

FIG. 3b shows how the outer edge of the enlarged diameter portion 82a is embedded and fixed to the base of the diaphragm member. On the other hand, the reduced diameter portion 82b is not fixed to the base of the diaphragm member, and a gap D is shown between the inner peripheral surface 84c of the outflow chamber 84 and the outer edge 82d of the reduced diameter portion 82b. ing. Therefore, an arc-shaped slit 85 is formed by the outer edge of the non-fixed portion and the inner peripheral surface of the base.

In the present invention, the enlarged diameter portion corresponds to the fixed portion, and the reduced diameter portion corresponds to the non-fixed portion or the movable portion.

FIG. 3c shows that the base of the throttle member 80 is formed with a stopper 86 that abuts against the reduced diameter portion 82b from the inflow chamber 83 side. Therefore, the non-fixed portion or movable portion can be deformed toward the outflow chamber 84 side by the inflow pressure of the brake fluid that has flowed into the inflow chamber 83 . It has a structure that does not deform due to

Although FIGS. 3a to 3c show an embodiment in which both the enlarged diameter portion 82a and the reduced diameter portion 82b have a substantially semicircular shape, the shape is not limited to this shape, and the desired elasticity can be achieved. The shape may be changed as appropriate to obtain characteristics. Specifically, the region of the non-fixed portion may be increased by forming a fan shape with a central angle of 180° or less for the enlarged diameter portion 82a and a central angle of 180° or more for the reduced diameter portion 82b. As a result, even if the inflow pressure of the brake fluid that has flowed into the inflow chamber is lower, the movable portion can be more easily deformed toward the outflow chamber.

Stainless steel, copper metal, nickel alloy, titanium alloy, or the like can be used as the material of the partition member 82, and the material can be appropriately selected according to the elastic properties required for the movable portion. Further, by forming the base body 81 from a synthetic resin, the partition member can be formed integrally with the base body by insert molding.

Next, the flow of the brake fluid and the action and effect of the throttle member will be described with reference to FIGS. 2 and 4. FIG.
When the pump 60 and throttle member 80 are mounted on the housing 51 as shown in FIG. 2, the brake fluid flows as follows when the pump 60 is driven.

When the drive shaft 57 is rotated by a drive source (not shown) and the eccentric portion 57a formed on the drive shaft 57 moves toward the piston 62, the piston 62 moves against the biasing force of the spring 67 to move the cylinder 61. pushed to the side. As a result, the pressure in the pump chamber 63 increases, the ball valve 64a is separated from the valve seat 64b, and the discharge valve 64 is opened. As a result, the brake fluid in the pump chamber 63 is discharged from the discharge port 65b to the discharge chamber 54 through the through hole 61c and the bottomed hole 65a of the cover 65. As shown in FIG.

When the drive shaft 57 rotates further and the eccentric portion 57 a formed on the drive shaft 57 begins to rotate away from the piston 62 , the piston 62 moves away from the cylinder 61 due to the biasing force of the spring 67 . continue. As a result, the pressure in the pump chamber 63 is lowered, the ball valve 64a is seated on the valve seat 64b, the discharge valve 64 is closed, and the opening of the bottomed hole 62b of the piston 62 is openably closed. the valve opens. Thereby, the brake fluid in the annular flow path 56 flows into the pump chamber 63 through the filter 70, the suction port 62c and the bottomed hole 62b.

When the drive shaft 57 rotates further and the eccentric portion 57a formed on the drive shaft 57 moves toward the piston 62 again, the piston 62 is pushed toward the cylinder 61 as described above, and the pump chamber 63 is pushed. of the brake fluid is discharged into the discharge chamber 54 from the discharge port 65b. In this manner, the piston 62 reciprocates repeatedly in the axial direction of the cylinder 61, selectively opening and closing the suction valve and the discharge valve 64 (not shown), thereby increasing the hydraulic pressure, that is, increasing the pressure of the brake fluid. , is discharged into the discharge chamber 54 from the discharge port 65b. Therefore, pulsation occurs in the brake fluid pressurized by the pump 60 .

The brake fluid discharged to the discharge chamber 54 flows into the inflow chamber 83 of the throttle member 80 through the inflow opening 83b of the inflow chamber of the throttle member 80 .
When the hydraulic pressure of the brake fluid in the inflow chamber 83 is lower than the specified pressure, the brake fluid flows into the outflow chamber 84 through the communication hole 82c provided in the partition member, as shown in FIG. 4a.
On the other hand, when the pressure of the brake fluid in the inflow chamber 83 reaches or exceeds the specified pressure, as shown in FIG. The brake fluid flows into the outflow chamber 84 from the opened opening. At this time, the pulsation of the brake fluid that has flowed into the inflow chamber 83 can be effectively reduced by the throttle effect generated when the non-fixed portion is deformed. 13 flows into the middle portion 13b.

4 shows an embodiment in which a buffer member 86 is provided inside the inflow chamber 83. As shown in FIG. By providing the buffer member 86 in the inflow chamber 83, the pulsation of the brake fluid flowing into the inflow chamber 83 can be temporarily reduced in the inflow chamber 83, so that the pulsation damping effect can be further increased.
The cushioning member 86 shown in FIG. 4 is a substantially cylindrical member made of elastomer or the like, having a corrugated portion 86a on the side wall and through holes 86b with openings at both ends. The pulsating brake fluid flowing from the inflow opening 83b applies pressure to the inner wall of the through-hole 86b when passing through the through-hole 86b of the buffer member 86 . At this time, the cushioning member 86 is elastically deformed outward to absorb the pressure of the brake fluid, thereby reducing the pulsation of the brake fluid.

<Effect of hydraulic pressure control unit 50>
Effects of throttle member 80 and hydraulic pressure control unit 50 according to the present embodiment will be described.
Since the throttle member 80 has a sleeve-shaped base body with a substantially uniform outer diameter, the throttle member can be installed without applying additional processing to the housing of the brake hydraulic unit.

Since the non-fixed portion deforms in accordance with the pressure of the brake fluid flowing into the inflow chamber, a throttle corresponding to the magnitude of the pulsating pressure can be obtained, and an optimum pulsation reducing effect can be obtained.

Since the base of the throttle member has a stopper that abuts against the non-fixed portion from the inflow chamber side, the non-fixed portion can be prevented from deforming toward the inflow chamber side. pulsation reduction effect can be reliably obtained.

Since the partition member is designed to form an arc-shaped slit between the outer edge of the non-fixed portion and the inner wall of the base, the non-fixed portion or movable portion can be easily designed.

Since the throttling member can be connected to other throttling members, the optimum degree of throttling can be adjusted according to the discharge pressure of the pump, and the pulsation reduction effect can be easily adjusted according to the vehicle. becomes. At least one of the connected throttle members may be a throttle member that does not have the communication hole 82c. Thereby, it is possible to prevent the brake fluid from flowing back from the outflow chamber to the inflow chamber.

Since the throttle member has a fixed portion that is immovably fixed within the discharge flow path, it is possible to reliably implement the throttle effect and the pulsation reduction effect of the throttle member.

Since the partition member is made of metal and the base is made of synthetic resin, the diaphragm member can be easily manufactured by insert molding. Also, by appropriately changing the type and shape of the metal, a desired drawing effect can be obtained.

By providing the buffer member 86 in the inflow chamber, a greater pulsation reduction effect can be obtained.

1 brake system, 2 hydraulic circuit, 2a hydraulic circuit, 2b hydraulic circuit, 11 master cylinder, 12 wheel cylinder, 13 main flow path, 13a, 13b intermediate portion, 14 secondary flow path, 14a intermediate portion, 15 supply flow path , 16 brake pedal, 17 booster, 18 brake caliper, 19 brake pad, 20 rotor, 31 charging valve, 32 releasing valve, 33 accumulator, 35 first switching valve, 36 second switching valve, 37 damper unit, 50 Hydraulic pressure control unit 51 housing 52 controller 53 accommodation chamber 53a stepped portion 54 discharge chamber 55 annular flow path 56 annular flow path 57 drive shaft 57a eccentric portion 58 accommodation chamber 59 accommodation chamber 60 pump, 61 cylinder, 61a projection, 61b bottom, 61c through hole, 62 piston, 62a end, 62b bottomed hole, 62c suction port, 63 pump chamber, 64 discharge valve, 64a ball valve, 64b valve seat, 64c Spring 65 Cover 65a Bottomed Hole 65b Discharge Port 66 Seal Member 67 Spring 68 Guide Member 69 Seal Member 70 Filter 71 Partition Part 80 Diaphragm Member 81 Substrate 82 Partition Member 83 Inflow Chamber , 84 outflow chamber, 85 arcuate slit, 86 cushioning member, 100 vehicle, 140 discharge channel, 142 branch channel.

Claims (8)

a discharge passage (140) through which brake fluid pressurized by a pump is discharged;
a throttle member (80) in the middle of the discharge flow path (140);
In a hydraulic control unit of a braking system for a vehicle comprising
The throttle member (80) includes a sleeve-shaped base body ( 81 ), an inflow chamber (83) into which the brake fluid flows, and an outflow chamber (84) into which the brake fluid flows out. a partition member (82) for partitioning,
The partition member (82) has a fixed portion (82a) fixed to the base ( 81) and a non-fixed portion (82b) not fixed to the base (81) ,
The base body (81) has a stopper (86) that contacts the non-fixed portion (82b) from the inflow chamber (83) side,
hydraulic control unit. The non-fixed portion (82b) is a variable portion that deforms toward the outflow chamber (84) according to the inflow pressure of the brake fluid flowing into the inflow chamber (83).
A hydraulic control unit according to claim 1. The non-fixed portion (82b) has a semicircular or fan shape, and the outer edge of the non-fixed portion (82b) and the inner wall of the base form an arc-shaped slit hole,
3. The hydraulic control unit according to claim 1 or 2 . The diaphragm member (80) has a connecting portion (84a) that connects with the other diaphragm member,
A hydraulic control unit according to any one of claims 1 to 3 . The throttle member (80) has a fixed portion that is held by the inner wall of the discharge channel (140) and fixes the throttle member so as not to move in the discharge channel,
A hydraulic control unit according to any one of claims 1 to 4 . The partition member (82) is formed of metal,
A hydraulic control unit according to any one of claims 1 to 5 . The substrate (81) is made of a synthetic resin,
A hydraulic control unit according to any one of claims 1 to 6 . 8. The hydraulic control unit according to any one of claims 1 to 7 , wherein said throttle member (80) comprises a buffer member mounted in said inflow chamber of said base body.

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