JPH0423723Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a dual-type brake valve used in a service brake system of a fully hydraulic power brake, and in particular, the invention relates to a dual-type brake valve used in a service brake system of a fully hydraulic power brake. The present invention relates to a type of device which is effective for use in controlling braking for front wheels and rear wheels of an automobile, for example.

[Conventional technology]

As a brake valve that simultaneously controls braking for the front and rear wheels of a car, a primary spool that controls the front wheel system and a secondary spool that controls the rear wheel system are installed in parallel with each other in series. Some are configured so that the two are directly abutted to transmit operating force and return force to each other.

[The problem that the idea attempts to solve]

However, in such a brake valve, the volume of the brake cylinder is larger than that of the primary system.
In the case of a secondary system, the secondary system's braking pressure returns the secondary spool and the primary spool at the same time, so the primary system's inlet is immediately closed and the primary system's braking pressure reaches the required control pressure. There are inconveniences such as not being able to reach the destination or causing an extreme time delay.

An object of the present invention is to provide a brake valve that can always balance and control the brake control pressures of the primary system and the secondary system.

[Means to solve the problem]

The brake valve according to the present invention is a dual type brake valve for an all-hydraulic power brake system configured to simultaneously control a front hydraulic circuit and a rear hydraulic circuit with a single brake pedal, and includes: body 1; slidably inserted into body 1;
Input member 2 connected to the brake pedal
, a driving side spring retainer 7 fixed to one end of the input member 2, a driven side spring retainer 8 fitted to the body 1 so as to be slidable in the axial direction, and both retainers 7 and 8. Reaction springs 9 and 10 are interposed between the input member 2 and the input member 2 to transmit the movement of the input member 2 to the driven retainer 8 via the drive retainer 7.
, a front system directional control valve 20A and a rear system directional control valve 20B, and the front system and rear system directional control valves 20A and 20B are provided in the body 1 so as to be arranged in series with each other. Primary valve chamber 21A
and a secondary valve chamber 21B, and a primary spool 2 fitted slidably in the direction aligned with both valve chambers 21A, 21B.
2A and secondary spool 22B, and a primary return spring device chamber 23A and a secondary return spring device chamber 23B formed on each side of both valve chambers 21A and 21B in the body 1 so as to be in series on a coaxial extension line with each other. And, primary side return spring device chamber 23A
Insert the primary spool 22A into the input member 2.
A primary return spring 25A is installed in the secondary spring device chamber 23B and a secondary return spring 25B is installed in the secondary spring device chamber 23B so as to urge the secondary spool 22B in the direction of the input member 2. In this brake valve, a holder 13 is axially arranged and fixed to the end face of the secondary spool 22B on the primary spool 22A side, and a spring seat 14 is attached to the holder 13 in the axial direction. A spring 15 is slidably fitted to the outside of the seat 14.
The spring 15 is inserted between the primary spool 22A and the secondary spool 22B in a state of stored force and is inserted externally. The holder 1 is configured to
3 restricts the position of the spring seat 14 on the input member 2 side, thereby allowing both spools to approach only within a predetermined range. It is characterized in that its biasing force is set to be larger than that of 25A, 25B and the reaction spring 10.

[Effect]

According to the above-mentioned means, when the volume of the brake cylinder is greater than that of the primary system, even if the secondary spool is returned to the pressure holding position earlier than the primary spool due to the pressure of the control port of the secondary system, the pressure between the two spools is The primary spool continues to be pushed by the deflection of the spring installed in the primary spool, so oil continues to flow without closing the inlet port. Then, after the pressure at the primary system control port becomes the same as the pressure at the secondary system control port, the primary spool is returned to the pressure holding position. Therefore, either control port will reach the required control pressure and there will be no extreme time delay.

〔Example〕

FIG. 1 is a longitudinal sectional view showing a dual type brake valve which is an embodiment of the present invention, and FIG. 2 is an enlarged partial sectional view thereof.

In this embodiment, the brake valve according to the present invention is configured so that a front hydraulic circuit and a rear hydraulic circuit are controlled simultaneously by a single brake pedal, and includes a body 1 consisting of a plurality of blocks. ing. At the left end of the body 1 (hereinafter, left and right and top and bottom are as shown in Fig. 1),
An input member 2 is inserted and supported slidably in the longitudinal direction, and a push rod 3 connected to a brake pedal (not shown) abuts against the protruding end of the input member 2 via a spherical joint 4. It is being A retractable dustproof cover 5 is attached between the right end of the push rod 3 and the body 1 so as to surround the abutment between the input member 2 and the push rod 3.

A large hollow part 6 is arranged in the middle part of the body 1 and is arranged along the axis, and a drive side spring retainer 7 is bolted to the right end part of the input member 2 inserted into the hollow part 6. It is fixed by appropriate means such as. Further, a driven side spring retainer 8 is fitted near the right end of the hollow portion 6 so as to be slidable in the left and right direction, and two-turn reaction springs 9 and 10 are disposed between the left and right retainers 7 and 8. are arranged inside and outside. Therefore, the movement of the input member 2 is transmitted to the driven retainer 8 via the drive retainer 7 and the springs 9 and 10.

On the other hand, in the right half of the body 1, a front system directional control valve 20A and a rear system directional control valve 20B are installed on the left and right, respectively. That is, on the right side of the driven side retainer 8 in the body 1, there are directional control valves 20 for the front system and the rear system.
The valve chambers 21A and 21B in A and 20B are arranged on the left and right so that they are lined up in series with each other, and are opened coaxially with the axial extension line of the hollow portion 6. Primary spool 22A and secondary spool 22 in system and rear system directional control valves 20A, 20B
B are fitted in each so as to be slidable in the longitudinal direction.

Here, the primary spool 22A has a connecting portion 11 integrally connected to its left end surface, and when the connecting portion 11 is inserted into the driven side retainer 8 and engaged with the stopper ring 12, the retainer 8 are connected so that they move together. On the other hand, a holder 13 is disposed on the left end surface of the secondary spool 22B on the axis and fixed by suitable means such as screwing.
A spring seat 14 is externally fitted to be slidable in the axial direction. Further, a spring 15 is inserted into the holder 13 and inserted between the seat 14 and the secondary spool 22B in a stored state, and this spring 15 is inserted into the spring seat 1.
4, the primary spool 22A and the secondary spool 22B are always biased in the direction of separating them from each other, and the left limit position of the spring seat 14 is restricted by the holder 13. It is configured to allow both spools to approach each other only within a predetermined range. Furthermore, a passage 16 is provided at a position opposite to the gap between the primary spool 22A and the secondary spool 22B in the body 1 so as to communicate this gap with a passage 36 to be described later.
Thereby, this space is communicated with the tank port.

Each return spring device chamber 23 is located on the left side and right side of both valve chambers 21A and 21B in the body 1.
A and 23B are formed to be in series with each other on a coaxial extension line, and the left end of the primary spool 22A and the right end of the secondary spool 22B are inserted into both device chambers, respectively. A primary return spring 25A is disposed in the primary return spring device chamber 23A, and is configured to urge the primary spool 22A to the left via the retainer 8. Spring device chamber 23 on the other secondary side
B is the secondary side return spring 25B
is arranged to bias the secondary spool 22B to the left via the spring retainer 24B. In the neutral state of the spools 22A, 22B, the repulsive force of both springs 25A, 25B overcomes the repulsive force of the reaction spring 10 disposed on the left side of the spools 22A, 22B, and the spring retainer 8 is moved into the hollow portion 6.
It is configured to be pressed against the stepped side surface of the housing to restrict the neutral position. And spring 10,
For 15, 25A and 25B, the assembly load is spring 10<spring 25A, 25B.
<Spring 15. Further, at the bottom of the secondary spring device chamber 23B, a seat portion 26B for receiving a reaction force of a plunger, which will be described later, is disposed on the axis and protrudes leftward.

Both spools 22, 22B have respective valve passages 27A, 2.
7B are arranged approximately at the center in the length direction,
It is formed by cutting the outer periphery into an annular groove shape with a constant width and a constant depth, and the valve passage 27A,
Left and right valve seats 28A and 28B and 29A and 29B are formed on both sides of 27B, respectively. In both valve chambers 21A and 21B, front system and rear system control ports 30A and 30B are arranged approximately in the center in the length direction, respectively, and the inner periphery is cut into an annular groove shape of a constant width and a constant depth. One port 30A is connected to a front brake actuation device (not shown) through a passage 31A, and the other port 30B is connected to a rear brake actuation device (not shown) through a passage 31B. are connected to each. A tank port 32 is located on the left side of the control ports 30A and 30B in both valve chambers 21A and 21B.
A and 32B are respectively formed in an annular groove shape, and both tank ports 32A and 32B are connected to a tank (not shown) via a passage 33. Furthermore, input ports 34A and 34B are formed in an annular groove shape on the right side of the control ports 30A and 30B, respectively, and both ports 34A and 34B are connected to a passage 35.
A and 35B are connected to a front accumulator and a rear accumulator (not shown), respectively.

In a neutral state where the brake pedal is not depressed, the control ports 30A, 30B and the tank ports 32A, 32B are connected to the valve paths 27A, 27B.
The control port 30 also communicates with the control port 30.
A, 30B and input ports 34A, 34B are blocked by right valve seats 29A, 29B.

A communication passage 36 is provided above the left and right valve chambers 21A, 21B in the body 1, and the passage 16 is connected to the hollow portion 6, the return spring device chambers 23A, 23B, and the space between the left and right spools 22A, 22B; and a passage 33 are opened in the left-right direction so as to communicate with each other, and a throttle valve 37 is interposed in this communication passage 36.

The left and right spools 22A and 22B have front and rear reaction cylinder chambers 38A,
38B are arranged on the axes of the right end portions of both spools, and plungers 39A, 38B are provided in these cylinder chambers 38A, 38B.
39B are fitted in a slidable manner, respectively. The primary plunger 39A is abutted against the holder 13 fixed to the secondary spool 22B, and the secondary plunger 39B is abutted against the seat portion 26B. In addition, front and rear pilot passages 40A and 40B are located in the middle of both spools 22A and 22B.
They are opened to connect the front system control port passage 31A and cylinder chamber 38A, and the rear system control port passage 31B and cylinder chamber 38B, respectively, and these pilot passages 40A, 4
0B are each formed to substantially constitute a throttle valve. That is, both plungers 39
A, 39B are the reaction cylinder chambers 3 when pressure is applied to the control port passages 31A, 31B.
Both spools 22A, 22B are biased to the left by the acting force of the pressures 8A, 38B.

Next, the effect will be explained.

When the brake pedal is gradually depressed and the push rod 3 is pushed to the right, the input member 2
is pushed to the right, the primary spool 22A is pushed to the right via the reaction springs 9 and 10, the retainers 7 and 8, and the connecting portion 11. When the primary spool 22A is pushed to the right, the secondary spool 22B, which is linked to the primary spool 22A via the spring seat 14 and the spring 15, is also pushed, so both spools 22A and 22B constantly push back against these spools. By being pushed against the return springs 25A and 25B that urge the valve chambers 21A and 21B, the valve chambers 21A and 21B are slid to the right, respectively. At this time, both spools 22
As the springs A and 22B move, the oil accumulated in the return spring device chambers 23A and 23B is released to the tank port passage 33 through the passage 36.

When both spools 22A, 22B are pushed and moved to the right, the valve passage 27 first opens in the neutral state.
Each control port 3 communicated with A and 27B
0A, 30B and tank ports 32A, 32B are blocked by left valve seats 28A, 28B, respectively. Next, in the neutral state, the right valve seat 2
Each control port 30A, 30B and input port 34A, 3 which were blocked by 9A, 29B respectively
4B are communicated with each other through valve passages 27A and 27B.

As a result, the pressure in the front system accumulator is changed from passage 35A to input port 34A to valve passage 27A.
→Control port 30A→Passage 31A to the front system brake actuating device, Rear system accumulator pressure is passed through passage 35B→Input port 34B→
Since the brake fluid is simultaneously supplied to the rear brake actuation device via the valve passage 27B, control port 30B, and passage 31B, proper brake operation is performed through cooperation between both systems.

On the other hand, when pressure is supplied to the control port passages 31A and 31B, the pressure is applied to the pilot passage 40.
Each reaction cylinder chamber 3 through A and 40B
8A and 38B, respectively. Due to this supply, each spool 22A, 22B is pushed back to the left with an acting force corresponding to the supply pressure. This pushing back force is transmitted to the brake pedal via the primary spool 22A, retainers 7, 8, springs 9, 10, input member 2, and push rod 3, so the brake operator can control the amount of operation he or she applied. You will get a feeling of operation commensurate with that.

When the brake pedal is released, both spools 22A and 22B are pushed back to the left by the return springs 25A and 25B, so the input ports 34A and 34B are closed by the valve seats 29A and 29B, respectively. At the same time, each control port 30A, 30B is connected to the valve passage 27A,
27B communicates with tank ports 32A and 32B. As a result, the hydraulic pressure supply to the front and rear brake actuation devices is stopped, and the pressure oil of the brake actuation devices in both systems is transferred from the passages 31A, 31B to the control port 30A.
30B → Valve path 27A, 27B → Tank port 32
A, 32B → via passage 33, and is discharged to the tank. As a result, the brake actuating devices of both systems simultaneously release the brake actuation.

In the brake operation, if the volume of the brake cylinder (not shown) is primary system < secondary system, the control port 30 of the primary system
The pressure at A reaches the control pressure earlier than at the control port 30B of the secondary system. Since this pressure passes through the pilot passage 40A and is guided to the reaction cylinder chamber 38A, the primary spool 22A reaches the pressure holding position (the valve seat 28A closes the tank port 32A and the valve seat 29A is returned to the position where it blocks input port 34A). However, the secondary spool 22B is operated by the plunger 39A and the holder 1 due to the control pressure of the reaction cylinder chamber 38A.
Can be held down through 3. When the control pressure of the secondary system control port 30B reaches the control pressure of the primary system control port 30A, the secondary spool 22B moves to the pressure holding position (the valve seat 28B closes the tank port 32B and the valve The seat 29B is returned to the position where it blocks the input port 34B.

Conversely, if the volume of the brake cylinder is primary > secondary, even if the secondary spool 22B is returned to the pressure holding position earlier than the primary spool 22A due to the pressure in the control port 30B of the secondary system, both spools 22A and 2
Since the primary spool 22A continues to be pushed by the deflection of the spring 15 inserted between the primary spool 22A and the primary spool 22A, the inlet port 34A continues to supply oil without closing. And the control port 30 of the primary system
After the pressure at A becomes the same pressure as the control port 30B of the secondary system, the primary spool 22A is returned to the pressure holding position.

In this way, according to the present embodiment, even if the volume of the brake cylinder is different in any direction, the required braking pressure can be always supplied without extreme delay in operation. Normal brake operation can be ensured.

[Effect of idea]

As explained above, according to the present invention, even if the volumes of the brake cylinders are different, the required braking pressure can be supplied without extreme delay in operation, so that the brakes always operate normally. can be ensured.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing a brake valve as an embodiment of the present invention, and FIG. 2 is an enlarged partial sectional view thereof. 1...Body, 2...Input member, 3...
Push rod, 4... Spherical joint part, 5... Dust cover, 6... Hollow part, 7, 8... Spring retainer, 9, 10... Reaction spring,
11... Connection portion, 12... Stopper ring, 13
...Holder, 14...Spring seat, 15...
...Spring, 16...Passage, 20A...Front system directional control valve, 20B...Rear system directional control valve,
21A, 21B...Valve chamber, 22A...Primary spool, 22B...Secondary spool, 23
A, 23B...Return spring device chamber, 24
B... Spring seat, 25A, 25B... Return spring, 26B... Seat part, 27
A, 27B...Valve path, 28A, 28B, 29A,
29B... Valve seat, 30A, 30B... Control port, 31A, 31B... Passage, 32A, 32B...
...tank port, 33...passage, 34A, 34B
... Input port, 35A, 35B ... Passage, 36
...Communication path, 37...throttle valve, 38A, 38B...
...Reaction cylinder chamber, 39A, 39B...
Plunger, 40A, 40B... passage.

Claims (1)

[Scope of Claim for Utility Model Registration] A dual-type brake valve for a full hydraulic power brake system configured to simultaneously control a front hydraulic circuit and a rear hydraulic circuit using a single brake pedal, body 1; slidably inserted into body 1;
Input member 2 connected to the brake pedal
, a driving side spring retainer 7 fixed to one end of the input member 2, a driven side spring retainer 8 fitted to the body 1 so as to be slidable in the axial direction, and both retainers 7 and 8. Reaction springs 9 and 10 are interposed between the input member 2 and the input member 2 to transmit the movement of the input member 2 to the driven retainer 8 via the drive retainer 7.
, a front system directional control valve 20A and a rear system directional control valve 20B, and the front system and rear system directional control valves 20A and 20B are provided in the body 1 so as to be arranged in series with each other. Primary valve chamber 21A
and a secondary valve chamber 21B, and a primary spool 2 fitted slidably in the direction aligned with both valve chambers 21A, 21B.
2A and secondary spool 22B, and a primary return spring device chamber 23A and a secondary return spring device chamber 23B formed on each side of both valve chambers 21A and 21B in the body 1 so as to be in series on a coaxial extension line with each other. And, primary side return spring device chamber 23A
Insert the primary spool 22A into the input member 2.
A primary return spring 25A is installed in the secondary spring device chamber 23B and a secondary return spring 25B is installed in the secondary spring device chamber 23B so as to urge the secondary spool 22B in the direction of the input member 2. In this brake valve, a holder 13 is arranged on the axis and fixed to the end face of the secondary spool 22B on the primary spool 22A side, and a spring seat 14 is attached to the holder 13 in the axial direction. The spring 15 is slidably fitted onto the seat 14.
The spring 15 is inserted between the primary spool 22A and the secondary spool 22B in a state of stored force and is inserted externally. The holder 1
3 restricts the position of the spring seat 14 on the input member 2 side, thereby allowing both spools to approach only within a predetermined range. A brake valve characterized in that its biasing force is set to be greater than that of 25A, 25B and the reaction spring 10.