JPH0714183U - Check valve assembly for hydraulic brake booster - Google Patents

Abstract

(57) [Abstract] [Purpose] A filter is installed inside a check valve assembly for a hydraulic brake booster without increasing its size. The check valve assembly for a hydraulic brake booster includes a pump discharge check valve 6 and an accumulator pressure accumulation check valve 8. The upstream pump discharge check valve 6 includes a ball valve 28,
The valve seat 33 on which the ball valve 28 is seated, and the spring 3 for urging the ball valve 28 toward the valve seat 33 side.
0, the ball valve 28 and the spring 30 are housed and held in the holding frame 32. In this holding frame 32,
A stopper 34 for restricting the movement limit of the ball valve 28 is provided. Further, a filter 38 is integrally provided on the side of the holding frame 32 opposite to the ball valve 28.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a check valve, and more particularly to a check valve assembly used in a hydraulic brake booster system.

[0002]

[Prior art]

 FIG. 9 is a system diagram of a conventional hydraulic brake booster. An example of a conventional hydraulic brake booster system will be described with reference to this figure. The pedaling force applied to the brake pedal 102 is increased via the hydraulic booster 104 and transmitted to the master cylinder 106, and the hydraulic pressure generated by the master cylinder 106 is applied to the front and rear wheel cylinders 108, 110. It is sent and acts as a brake. The hydraulic booster 104 is operated by the hydraulic pressure of an accumulator 116, and the accumulator 116 is accumulated by a pump 114 driven by a motor 112. A check valve 120 is provided on the discharge side of the pump 114, and the accumulator 116 accumulates pressure through the check valve 120, and the check valve 120 holds the hydraulic pressure accumulated in the accumulator 116. It Between the check valve 120 and the accumulator 116, a motor operating pressure switch 122 that is turned on when the hydraulic pressure of the accumulator 116 is released and drops to a predetermined value to operate the motor 112, and the motor operating pressure switch 122. An alarm pressure switch 124 is connected to turn on and issue an alarm when the hydraulic pressure of the accumulator 116 drops to a set hydraulic pressure lower than the hydraulic pressure for operating the pump 114 due to a failure of the switch 122 or the like. Further, a filter 118 is provided on the supply port side of the hydraulic booster 104 to which the brake fluid is supplied from the accumulator 116. Reference numeral 126 is a master cylinder brake fluid tank, and 128 is a hydraulic booster brake fluid tank.

In this conventional hydraulic brake booster system configuration, a filter 118 for removing foreign matter such as abrasion powder generated by the operation of the pump 114 and mixed in the brake fluid is provided in the accumulator 116. It is provided only at the inlet of the supply port for supplying the accumulated hydraulic pressure to the hydraulic booster 104. The check valve 120 for pump discharge is also used as a check valve for holding the hydraulic pressure accumulated in the accumulator 116.

In the conventional configuration as described above, foreign matter such as metal abrasion powder generated inside the pump is attached to the seat portion of the pump discharge check valve 120 that also serves as the check valve for accumulating the accumulator 116. If adhered, the seat of the valve body becomes incomplete and the accumulated pressure in the accumulator 116 leaks. As a result, the driving time of the pump 114 for accumulating pressure in the accumulator 116 becomes long, the life of the pump 114 and the motor 112 becomes short, and when the engine is started after being parked for a long time. In addition, there was a problem that the accumulator 116 became insufficient in pressure accumulation.

In order to solve this problem, a filter is provided on the upstream side of a pump discharge check valve (also used for accumulator pressure accumulation) 120 to filter the brake fluid before flowing into the check valve 120. Then, the volume of the pump chamber increases correspondingly, so that there is a problem that the compression ratio of the pump is reduced and the pump performance is reduced, or the air bleeding property of the pump is reduced. In addition, at the mounting position on the upstream side of the pump discharge check valve 120, there is a problem that the filter is required to have high strength and becomes large in size because the pressure change is large. Then, as shown in FIG. 10, a check valve 120 on the discharge side of the pump and a check valve 130 for accumulating the accumulator 116 are separately provided, and a filter 132 is provided between these two check valves 120, 130. It is considered to be placed.

[0006]

[Problems to be solved by the device]

 As described above, in the configuration in which the filter 132 is disposed between the check valve 120 for discharge and the check valve 130 for accumulator pressure accumulation, there is a problem that a large space is required because these three members 120, 130, 132 are arranged in series. there were. In particular, each of the check valves 120 and 130 described above urges the ball valves 120a and 130a, the seats 120b and 130b on which the ball valves 120a and 130a are seated, and the ball valves 120a and 130a toward the seats 120b and 130b. When the ball valves 120a and 130a move to compress the springs 120c and 130c, the coils of the springs 120c and 130c come into close contact with each other to form a brake fluid passage. Ball stoppers 120d and 130d for restricting the movement limits of the ball valves 120a and 130a are provided so as not to be blocked. Therefore, there is a problem that the check valves 120 and 130 originally have a long length, but the length is further increased by inserting the filter 132 therebetween.

The present invention has been made to eliminate the above-mentioned drawbacks. A check valve for accumulator pressure accumulation is provided separately from a check valve for pump discharge, and a filter is arranged between these check valves to check the accumulator pressure accumulation valve. A hydraulic type that can be manufactured at low cost without foreign matter such as wear powder generated by the operation of the pump sticking to the seat part of the machine and leaking the accumulated pressure of the accumulator, and without increasing the size as a whole. An object of the present invention is to provide a check valve assembly for a brake booster.

[0008]

[Means for Solving the Problems]

 The check valve assembly for a hydraulic brake booster according to the present invention accumulates the pressure fluid discharged from the pump through the discharge check valve in the accumulator through the pressure check valve, and the hydraulic pressure of the accumulator is stored. It is used in a hydraulic brake booster that activates a hydraulic booster by means of the pump discharge check valve, the valve body, the valve seat on which this valve seats, and the valve body to the valve seat side. The holding frame body includes a biasing spring, a holding frame body that houses the valve body and the spring, and a stopper that is formed in the holding frame body and restricts the movement limit of the valve body. The feature is that a filter is integrally provided.

[0009]

[Action]

 In the check valve assembly for the hydraulic brake booster described above, the filter provided between the check valve for pump discharge and the check valve for accumulator pressure accumulation does not have to be an independent structure, but a stopper that restricts the movement limit of the valve body is formed. Since it is provided integrally with the holding frame, the check valve for pump discharge, the filter, and the check valve for accumulator accumulator do not increase in size even if they are arranged in series. Can be down.

[0010]

【Example】

 The present invention will be described below with reference to the embodiments shown in the drawings. FIG. 1 is a vertical cross-sectional view of a check valve assembly for a hydraulic brake booster (generally indicated by reference numeral 1) according to an embodiment of the present invention. The check valve assembly 1 contains a plunger pump 2. The pump discharge check valve 6 fixed to the discharge side of the pump body 4 arranged on the plunger pump 2 side, the accumulator pressure accumulation check valve 8 arranged on the downstream side, both check valves 6, And a filter (described in detail later) disposed between the eight. The plunger pump 2 advances and retracts the plunger 10 in the cylinder 4a by the rotation of an eccentric cam (not shown), and expands the pump chamber 14 when the plunger 10 is retracted, so that the pump chamber 14 is expanded through the suction valve 12. Brake fluid is sucked into 14 and, when the plunger 10 is moved forward, the pump chamber 14 is compressed and the brake fluid is discharged.

One end of a housing (valve housing) 16 of the check valve assembly 1 is inserted and fixed in a cylindrical opening 4 b formed in the pump body 4 by screwing. One end of a connector 18 is fitted to the outer end of the valve housing 16, and a bolt 20 penetrating the connector 18 is screwed and fixed to the inner surface of the end of the valve housing 16. The pump discharge check valve 6 is provided inside the portion of the valve housing 16 inserted into the cylindrical opening 4b, and the inside of the portion of the bolt 20 inserted into the valve housing 16 is accumulated. Check valves 8 for accumulating the rotor pressure are housed respectively. Between the inner surface of the cylindrical opening 4b of the pump body 4 and the outer surface of the valve housing 16, between the inner surface of the valve housing 16 and the outer surface of the connector 18, and between the inner surface of the connector 18 and the outer surface of the bolt 20. O-rings 22, 24, and 26 are respectively fitted to these so as to maintain liquid tightness between them.

A reduced diameter portion 16a is formed at substantially the center of the cylindrical space inside the valve housing 16, and the valve element of the pump discharge check valve 6 (closer to the plunger pump 2 than the reduced diameter portion 16a). (Ball valve) 28, a coil spring 30 for urging the ball valve 28, and the like, and a holding frame 32 for holding the same. A valve seat 33, on which the ball valve 28 biased by the spring 30 is seated, is arranged at the tip of the holding frame 32 on the plunger pump 2 side, and is fixed by caulking the tip of the valve housing 16. There is.

As shown in FIGS. 2 and 3, the holding frame 32 has a large-diameter portion 32a having an opening at one end (close to the plunger pump 2) and a small-diameter portion continuously provided on the bottom side of the large-diameter portion 32a. 32b, and the ball valve 28 of the discharge check valve 6 and the coil spring 30 are housed in the large diameter portion 32a. A ball stopper 34 extending from the center of the small diameter portion 32b into the large diameter portion 32a is provided on the bottom portion of the small diameter portion 32b. The portion of the ball stopper 34 located inside the small diameter portion 32b is connected to the outer wall 32e of the small diameter portion 32b by two ribs 32c provided at symmetrical positions. Two bottom walls 32d that connect the central portion of the ribs 32c and the outer wall 32e to each other are provided at the bottoms of the ribs 32c that are offset by 90 degrees. The outer peripheral portion of the small-diameter portion 32b is open except for the portion integrated with the ribs 32c at the two locations and the portion connected to the bottom wall 32d at the two locations (that is, the outer wall 32e at the four locations), and the bottom is also Except for the ribs 32c at these two locations and the bottom wall 32d at the two locations between them, the ribs 32c are open, and a mesh 36 for filtration is attached to the inner surface and the top surface of the bottom of these outer walls 32e. Due to the small-diameter portion 32b of the holding frame 32 and the filtering mesh 36 attached to the inner surface of the small-diameter portion 32b, metal abrasion powder mixed in the brake fluid discharged from the plunger pump 2 and the like. A filter 38 for removing foreign matter is configured. Therefore, in this embodiment, when the ball valve 28 of the pump discharge check valve 6 moves, by restricting the movement limit thereof, it is possible to prevent the spring 30 from closely contacting and blocking the brake fluid passage. Therefore, the ball stopper 34 provided on the holding frame and the filter 38 are integrally formed.

Next, the structure of the accumulator pressure accumulation check valve 8 provided on the downstream side of the pump discharge check valve 6 will be described. A valve seat 42 having an O-ring 40 fitted to the outer periphery is inserted into the hole 16b on the downstream side of the central reduced diameter portion 16a of the valve housing 16. One end (the right end in FIG. 1) of the valve seat 42 is fitted into the tip portion of the bolt 20 screwed into the valve housing 16. A valve hole 20a for accommodating the accumulator pressure accumulating check valve 8 is formed inside the bolt 20, and further axially and diametrically internal passage 20b connected to an accumulator (not shown) is provided downstream thereof. , 20c are provided. A valve body (ball valve) 44 and a coil spring 46 for urging the ball valve 44 toward the valve seat 42 are housed in the valve hole 20a of the bolt 20. Further, a ball stopper 48 for restricting the movement limit of the ball valve 44 is provided on the bottom surface of the valve hole 20a. Inside the ball stopper 48, a passage communicating with the axial internal passage 20b is provided. The hole 48a is formed.

The operation of the check valve assembly 1 having the above configuration will be described. The brake fluid discharged from the pump chamber 14 as the plunger 10 of the plunger pump 2 moves back and forth in the cylinder 4a with the rotation of an eccentric cam (not shown), is stored in the ball seat 33 of the pump discharge check valve 6. The ball valve 28 is pushed open from the passage and enters the large diameter portion 32a of the holding frame 32. At this time, the ball valve 28 is restricted in its movement amount by the ball stopper 34, so that the spring 30 is not compressed and completely adheres, and the brake fluid passes between the coils of the spring 30. And flows out to the small diameter portion 32b side of the holding frame 32. The inside of the small-diameter portion 32b of the holding frame 32 is a space excluding two ribs 32c, and it enters into this space, and is used for filtering the space between the four outer walls 32e and the open portion of the bottom. It passes through the mesh 36, goes out of the holding frame 32, passes through the reduced diameter portion 16a in the valve housing 16, and flows out to the accumulator pressure check valve 8 side (see the arrow in FIG. 1). When the brake fluid passes through the filter 38 between the pump discharge check valve 6 and the accumulator pressure accumulation check valve 8, it is generated by the operation of the plunger pump 2 and is mixed in the discharged brake fluid. Foreign materials such as metal abrasion powder are removed.

The brake fluid that has passed through the passage in the ball seat 42 of the accumulator pressure check valve 8 bends the spring 46 and pushes the ball valve 44 open, and flows into the valve hole 20 a of the bolt 20. The accumulator pressure accumulation check valve 8 is also provided with a ball stopper 48 so that the spring 46 does not come into close contact with each other and a passage between the coils is secured. It flows out of the check valve assembly 1 through the passage hole 48a in the ball stopper 48 and the internal passages 20b, 20c of the bolt 20, and the pressure is accumulated in an accumulator (not shown). As described above, since the filter 38 is provided on the upstream side of the check valve 8 for accumulator pressure accumulation, the ball seat 42 of the check valve 8 for accumulator pressure accumulation contains wear powder and the like generated by the operation of the pump. Since it does not adhere, there is no risk that the accumulated pressure in the accumulator will leak due to a defective sheet. Moreover, since the filter 38 is provided integrally with the ball stopper 34 of the pump discharge check valve 6, the size of the check valve assembly 1 as a whole is not increased by providing the filter 38, and the cost is low. .

FIG. 4 and FIG. 5 show a filter 58 according to the second embodiment. Only the shape of the holding frame body 52 constituting the filter 58 is different from that of the first embodiment, and Since the structure of the part is the same, its illustration and description are omitted. In this embodiment, a conical ball stopper 54 is provided in a holding frame 52 that houses a ball valve and a spring of a pump discharge check valve. The conical ball stopper 54 rises from the center of the bottom of the small-diameter portion 52b of the holding frame 52, and has four ribs 52c formed on its outer surface at equal intervals in the circumferential direction. The bottoms of the ribs 52c at these four locations are connected to the outer wall 52e through four bottom walls 52d. The outer peripheral surface and the bottom of the small-diameter portion 52b are continuous with the four bottom walls 52d following the four ribs 52c and the bottom wall 52d (that is, the rib Parts other than the four outer walls 52e facing the outside of 52C are open. A filtering mesh 56 is attached to the inner surface of the small diameter portion 52b, and the small diameter portion 52b and the filtering mesh 56 constitute a filter 58. Since the filter 58 of the second embodiment is also provided integrally with the ball stopper 54 that regulates the movement of the ball valve of the pump discharge check valve, the overall length of the check valve assembly 1 can be shortened. The cost can be reduced.

FIGS. 6 to 8 show a third embodiment, in which the pump discharge check valve 66 and the filter 78 are different from those of the first and second embodiments in that the accumulator pressure accumulator is used. The structure of the check valve is the same, so the illustration and description of that part will be omitted. The holding frame 72 of this embodiment does not have the portions corresponding to the small-diameter portions 32b and 52b of the above-described embodiments, but is composed of only the large-diameter portions 32a and 52a. A ball valve 68 and a coil spring 70 are housed inside the holding frame 72, and a valve seat 73 is abutted on the opening side on the left side of the drawing by caulkingly fixed to the tip of a valve housing 64. The ball valve 68 urged by the spring 70 is seated. At the center of the bottom portion of the holding frame 72, a ball stopper 74 that restricts the movement limit of the ball valve 68 is formed.

The holding frame 72 has four bottom walls 72d connecting the bottom of the central ball stopper 74 and the outer peripheral portion, and an outer wall 72e following the bottom wall 72d, and the other portions are open. There is. A filtering mesh 76 is attached to the inner surface of the holding frame 72, and the holding frame 72 and the filtering mesh 76 constitute a filter 78 that removes foreign matter in the brake fluid. In this embodiment, since the ball stopper 74 is formed at the bottom of the portion of the holding frame 72 that accommodates the ball valve 68 and the coil spring 70, the filter mesh 76 is attached to form the filter 78. The total length of the check valve assembly 1 can be further shortened as compared with the above embodiments. The shape of the holding frame to which the filtering mesh is attached is not limited to that of each of the above-mentioned embodiments, and the filter is integrally formed with the member in which the ball stopper of the pump discharge check valve is formed. Anything provided with.

[0020]

[Effect of device]

 As described above, according to the present invention, the check valve for pump discharge of the check valve assembly for the hydraulic brake booster equipped with the check valve for pump discharge and the check valve for accumulator pressure accumulation is used as the valve body. It is composed of a valve seat, a spring, a stopper that regulates the movement limit of the valve body, and a holding frame that houses and holds the valve body, and a filter is provided integrally with the holding frame, so the overall size is large. It is possible to install a filter that removes foreign substances in the pump discharge liquid without causing deterioration, and it is possible to prevent the occurrence of seat defects in the accumulator pressure check valve, and reduce the number of parts. Therefore, it is possible to reduce the cost.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a check valve assembly for a hydraulic brake booster according to an embodiment of the present invention.

FIG. 2 is a plan view of a holding frame of the check valve assembly for the hydraulic brake booster.

3 is a view showing a holding frame of the check valve assembly for the hydraulic brake booster, which is taken along line III-III of FIG.
It is sectional drawing which follows the line.

FIG. 4 is a plan view showing another example of a holding frame body.

5 is a cross-sectional view taken along the line VV of FIG.

FIG. 6 is a vertical cross-sectional view of a main part of a check valve assembly for a hydraulic brake booster according to another embodiment.

7 is a plan view showing a holding frame body of the check valve assembly of FIG.

8 is a sectional view taken along the line VIII-VIII in FIG.

FIG. 9 is a system diagram of a conventional hydraulic brake booster.

FIG. 10 is a vertical cross-sectional view showing an example of a conventional check valve assembly for a hydraulic brake booster.

[Explanation of symbols]

 6 Pump discharge check valve 8 Accumulator pressure check valve 28 Valve body (ball valve) 30 Spring 32 Holding frame 33 Valve seat 34 Stopper 38 Filter

Claims (3)

[Scope of utility model registration request] 1. A hydraulic brake booster that stores pressure fluid discharged from a pump through a discharge check valve in an accumulator through a pressure check valve and operates a hydraulic booster by the hydraulic pressure of the accumulator. In the device, the discharge check valve, a valve body, a valve seat on which the valve body is seated, a spring for urging the valve body toward the valve seat, a holding frame body for housing the valve body and the spring, A check valve for a hydraulic brake booster, comprising a stopper formed on the holding frame body for restricting a movement limit of the valve body, and provided with a filter integrally with the holding frame body. Assembly. 2. The holding frame body is extended on the side opposite to the valve body,
The filter is integrally attached to the filter.
A check valve assembly for a hydraulic brake booster as described in. 3. The check valve assembly for a hydraulic brake booster according to claim 1, wherein a filter is provided inside the holding frame.