JPH11192931A - Air control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air control valve capable of increasing a brake pressurizing performance, improving air consumption, and preventing noise from occurring when a service brake is decompressed in brake application. SOLUTION: In an air control valve 10 comprising a hold diaphragm 15 and a decay diaphragm 17 which are arranged between a brake valve and an air master cylinder 4 for applying brake to a wheel by the action of air pressure force-fed from the brake valve and operated so that the air pressure force-fed from the brake cylinder is connected selectively to the air master cylinder or the connected air pressure is decompressed, a one-way valve 25 which allows air pressure to enter from the brake valve into a rear chamber of the decay diaphragm is provided in a flow path for communicating the rear chamber of the decay diaphragm to the brake valve, and a specified air pressure is sealed into the rear chamber when a brake is applied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air control valve for anti-lock / traction control suitable for a full air and air overhydraulic (AOH) brake system. The present invention relates to an air control valve capable of improving air consumption, improving air consumption, and preventing generation of abnormal noise when a brake is normally depressurized.

[0002]

2. Description of the Related Art As an air control valve, a type shown in FIG. 5 is conventionally known (for example, Japanese Patent Application Laid-Open No. Hei 8-230635). A brake system using the air control valve will be described with reference to the drawings.
1 is an air tank, 102 is a brake valve, 1
03 is a brake pedal, 104 is an air master cylinder,
105 is a brake cylinder, 106 is a relay valve, and these constitute a brake system.

In this brake system, when the brake pedal 103 is depressed, the brake valve 102 opens,
Air corresponding to the depression force of the brake pedal 103 is supplied from the air tank 101 to the air control valve 100 by the relay valve 106, and the air control valve 1
00 acts on the air master cylinder 104, where the air pressure is converted to hydraulic pressure and the brake cylinder 1
05 can be operated to apply the brakes. The air master cylinder 104 may be omitted, and the air pressure may be directly supplied to the brake cylinder 105.

The air control valve 100 has an input chamber 111 communicating with a relay valve 106 and an output chamber 1 communicating with an air master cylinder 104 in a main body, as shown in FIG.
12, an exhaust chamber 113 for releasing the air pressure to the atmospheric pressure is provided, and a hold valve 114, a hold diaphragm 115, a decay valve 116, and a decay diaphragm 117 are arranged in the flow paths communicating with each other as shown in the figure. I have. The input chamber 111 communicates with an output chamber 112 via a hold diaphragm 115, and the output chamber 112
Communicates with the exhaust chamber 113 via the decay diaphragm 117.

[0005] The hold valve 114 has a valve input port 114a, a valve output port 114b, and a valve exhaust port 114c. A plunger 114e for opening and closing the ports is disposed in the hold valve 114. The plunger 114e is provided with flow passage blocking members 114f and 114g at both ends. When the plunger 114e is urged upward in the figure by the return spring 114k, the flow passage blocking member 114f causes the valve input port 114a and the valve output port to be connected to each other. Port 11
4b, while the valve output port 114b
And the valve exhaust port 114c are in communication. When power is supplied to the solenoid 114d, the plunger 114e moves downward from the state shown in the figure against the urging force of the return spring 114k, and the valve input port 11
4a and the valve output port 114b are communicated with each other, and the valve output port 114b and the valve exhaust port 114c are shut off by the flow path shutoff member 114g. The hold diaphragm 115 is formed of an elastic body, and is constantly urged in a direction to close the communication between the input chamber 111 and the output chamber 112 by a return spring 115b disposed in the rear chamber 115a.

The decay valve 116 has a valve input port 116a, a valve output port 116b, and a valve exhaust port 116c, and a plunger 116e for opening and closing the respective ports is disposed in the decay valve 116. The plunger 116e is provided with flow passage blocking members 116f and 116g at both ends. The plunger 116e is normally urged downward in the drawing by a return spring 116k, and the valve blocking port 116g and the valve input port 116a and the valve discharge port. 116c, the valve output port 116b and the valve discharge port 116c are shut off, and the valve input port 116a is closed.
And the valve output port 116b. When power is supplied to the solenoid 116d, the plunger 116e
Moves upward from the state shown in FIG.
Valve input port 116a and valve output port 1
16b is shut off, and the valve output port 116b and the valve exhaust port 116c are communicated. The decay diaphragm 117 is made of an elastic material, and is always
The return spring 117b disposed in the position a is biased in a direction to close the communication between the output chamber 112 and the exhaust chamber 113.

As shown in FIG. 5, the hold valve 114 having the above structure has a valve input port 114a of the hold valve 114 in the input chamber 111 and a valve output port 11
4b is a rear chamber 115a of the hold diaphragm 115.
In addition, the valve exhaust port 114c is disposed so as to communicate with the atmosphere, and when not operating, the input chamber 111 and the back chamber 115
a is shut off by a hold valve 115, and a rear chamber 115a of the hold valve is connected to a valve exhaust port 114c.
Through the air. When the solenoid 114d of the hold valve 114 is energized and the plunger 114e is moved downward in the drawing, the input port 114a and the valve output port 114b are connected, and the valve output port 114b and the valve exhaust port 11 are connected.
4c is shut off, the input chamber 111 is communicated with the rear chamber 115a, and the rear chamber 115a is isolated from the atmosphere.

The decay valve 116 is connected to a valve input port 116 of the decay valve 116 as shown in FIG.
a is connected to the input chamber 111 through the passage 119, and the valve output port 116b is connected to the rear chamber 1 of the decay diaphragm 117.
17a, the valve exhaust port 116c communicates with the atmosphere, and when not in operation, communicates the valve input port 116a with the valve output port 116b (in other words, the input chamber 111 and the back chamber 117a of the decay diaphragm 117).
The rear chamber 117a is isolated from the atmosphere. When the solenoid 116d of the decay valve 116 is energized and the plunger 116e is moved upward in the drawing, the valve input port 116a and the valve output port 116b are shut off, and the valve output port 116b is closed.
And the valve exhaust port 116c are communicated with each other.
The rear chamber 117a of the decay diaphragm 117 is shut off, and the rear chamber 117a communicates with the atmosphere through the valve exhaust port 116c.

The operation of the brake pressure control device according to the above configuration will be described. When the brake pedal 103 is depressed, the brake valve 102 opens, and air corresponding to the depression force of the brake pedal 103 is supplied from the air tank 101 to the air control valve 100 via the relay valve 106. The air pressure flowing into the input chamber 111 of the air control valve 100 acts on the hold diaphragm 115, and moves the hold diaphragm 115 to the right in the drawing against the urging force of the return spring 115b to move the input chamber 1
11 and the output chamber 112 are communicated. The air pressure flows to the air master cylinder 104 through the opened flow path, and operates the brake cylinder 105 to operate the brake.

At this time, the air pressure also acts on the decay diaphragm 117 from the output chamber 112, but the input chamber 111 → the passage 119 → the valve input port 11 of the decay valve 116 is connected to the rear chamber 117a of the decay diaphragm 117.
6a → input chamber 111 via valve output port 116b
The decay diaphragm 117 does not open due to the air pressure from the air master cylinder 4.

When the brake pedal is released, the air pressure from the brake valve 102 becomes the atmospheric pressure. Therefore, the hold diaphragm 115 is opened by the air pressure from the air master cylinder 104 and the air pressure is supplied from the brake valve via the input chamber 111. It is released to the atmosphere and the brake is released. At this time, since the air pressure is acting on the rear chamber 117a of the decay diaphragm just before the end of the depressurization, the air master cylinder 104 and the exhaust chamber 113 are connected to each other by the decay diaphragm 1.
17 is in a state of being cut off. Immediately before the end of the decompression, the rear chamber 11 of the decay diaphragm 117
The air pressure of 7a is changed from the valve output port 116b of the decay valve 116 to the valve input port 116a to the passage 119.
→ When the atmospheric pressure is reached via the input chamber 111 → the brake valve, the decay diaphragm is pushed open by the air pressure of the air master cylinder 4, and the air pressure is released from the exhaust chamber 113 to the atmosphere via the decay diaphragm.

[At the time of anti-lock operation] At the time of brake operation, anti-lock control is started, and when a command for holding the brake pressure is issued, the solenoid 114 of the hold valve 114 is operated.
d, the plunger 114e moves downward in the figure, and the valve input port 114a of the hold valve 114
And the valve output port 114b are communicated with each other.
01 acts on the rear chamber 115a of the hold diaphragm 115, presses the hold diaphragm 115 to cut off the communication between the input chamber 111 and the output chamber 112, and the air pressure of the brake device is held at the air pressure at that time. You.

When a brake pressure reducing command is issued, the solenoids of the hold valve 114 and the decay valve 116 are energized, the plungers 114e and 116e are operated, and the valve input port 114a and the valve output port 114b of the hold valve 114 are connected. , Decay valve 1
16 valve output port 116b and valve exhaust port 1
16c is communicated, air pressure acts on the rear chamber 115a of the hold diaphragm 115, and the air pressure of the rear chamber 117a of the decay diaphragm 117 is released, so that the air pressure of the air master cylinder 104 pushes and opens the decay diaphragm 117. Then, the air is exhausted from the exhaust chamber 113 to the atmosphere, and the brake pressure is reduced. The pressurization during the antilock control is the same as that for the normal brake.

[0014]

However, in the brake device having the above-described configuration, the input chamber 1 is provided in the rear chamber 117a of the decay diaphragm 117 when the brake is normally applied.
11 → passage 119 → valve input port 116a of decay valve 116 → part of air pressure in input chamber 111 through valve output port 116b to actuate decay valve 1
17 is prevented from opening, but at that time the input room 111
From time to time, a part of the air pressure is applied to the rear
Therefore, the pressure response of the brake is deteriorated. In addition, the consumption of air pressure increases, and the capacity of the air tank needs to be increased in consideration of them. Further, immediately before the end of the depressurization during the normal brake depressurization, the air pressure in the rear chamber 117a of the decay diaphragm is reduced, and when the decay diaphragm is opened, the decay diaphragm vibrates for the following reasons, causing abnormal noise. is there.

That is, when the brake pressure is reduced, an air pressure difference occurs between the air pressure P1 in the rear chamber of the decay diaphragm and the air pressure P2 in the air master cylinder of the decay diaphragm due to flow path resistance and the like. <P2. At this time, if the pressure receiving area in the rear chamber of the decay diaphragm is A1, the pressure receiving area of the air master cylinder of the decay diaphragm (a donut-shaped pressure receiving area) is A2, and the spring force of the return spring of the decay diaphragm is F, then (A1 × When (P1 + F) <A2 × P2, the decay diaphragm is opened, and the air pressure of the air master cylinder is opened via the opened decay diaphragm → exhaust valve. Air pressure is released and P
When the air pressure difference between 1 and P2 becomes small, (A1 × P1 + F)> A2 × P2, and the decay diaphragm closes. From the above relationship, when the brake pressure is reduced, the decay diaphragm repeatedly opens and closes due to the relationship between the air pressures P1 and P2, which causes a problem that abnormal noise is generated. Also, at the start of the brake pressurization, the spring 115 prevents the decay diaphragm 117 from opening by the air pressure in the output chamber 112.
The hold diaphragm 115 is closed by the force of a, and the hold diaphragm 115 is opened after the air pressure is securely generated in the rear chamber 117a of the decay diaphragm 117. Therefore, the pressure response at the start of the brake pressure was poor.

Therefore, the present invention provides a one-way valve which permits air pressure to flow only from the brake valve to the rear chamber of the decay diaphragm in a flow path communicating the brake valve and the rear chamber of the decay diaphragm. An object of the present invention is to solve the above-described problem by improving the pressure responsiveness at the time of applying a brake by always enclosing a predetermined air pressure in the back chamber. Another object of the present invention is to prevent vibration of the decay diaphragm when the brake is depressurized by sealing the air pressure in the rear chamber of the decay diaphragm. Further, by containing the air pressure, the return spring in the rear chamber of the hold diaphragm can be eliminated, whereby the brake responsiveness at the time of pressurization can be further improved.

[0017]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a means for solving the problems which is arranged between a brake valve and an air master cylinder which applies a brake to wheels by the action of air pressure fed from the brake valve. And an air having a hold diaphragm and a decay diaphragm which operate to selectively communicate air pressure fed from the brake valve to the air master cylinder or to reduce the pressure of the communicated air pressure. In the control valve, a one-way valve that allows air pressure to flow from the brake valve to the back chamber of the decay diaphragm is provided in a flow path communicating the back chamber of the decay diaphragm and the brake valve, That the specified air pressure is contained in the chamber. An air control valve to a butterfly.

[0018]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of an air control valve according to an embodiment of the present invention. It should be noted that the present invention is characterized by the configuration of the air control valve, and the configuration of the brake system is not different from the conventional one. Therefore, the following description will focus on the air control valve.

Referring to FIG.
Is an input chamber 11 communicating with the brake valve 2 in the main body,
An output chamber 12 communicating with the air master cylinder 4 and an exhaust chamber 13 for releasing the air pressure to the atmospheric pressure via an exhaust valve 13a are provided, and a hold valve 14 as shown in FIG. Hold diaphragm 1
5, a decay valve 16 and a decay diaphragm 17 are arranged. The hold diaphragm 15 and the decay diaphragm 17 are formed of an elastic body such as rubber.
The input chamber 11 communicates with the output chamber 12 via the hold diaphragm 15 and further with the valve input port 16a of the decay valve 16 via the one-way valve 25 and the flow path 26. The output chamber 12 is a decay diaphragm 1
7 and communicate with the exhaust chamber 13.

The hold valve 14 has a valve input port 14a, a valve output port 14b, and a valve exhaust port 14c, like the conventional hold valve.
A return spring 14k, a solenoid 14d, and a plunger 14e for shutting off communication between the respective ports are arranged in the hold valve 14. The plunger 14e is provided with flow passage blocking members 14f and 14g at both ends, and is normally moved downward by the urging force of the return spring 14k.
a and the valve output port 14b are shut off.
The valve output port 14b communicates with the valve exhaust port 14c.

The valve input port 1 of the hold valve 14
4a is arranged to communicate with the brake valve, the valve output port 14b is arranged to communicate with the rear chamber 15a of the hold diaphragm 15, and the valve exhaust port 14c is arranged to communicate with the exhaust chamber 13.
When not operating, the brake valve and the rear chamber 15a are shut off, and the rear chamber 15a and the exhaust chamber 13 are in communication. When the solenoid 14d is energized, the plunger 14e moves upward from the state shown in the drawing against the urging force of the return spring 14k, connects the valve input port 14a and the valve output port 14b, and opens the valve by the flow path blocking member 14g. Output port 14b and valve exhaust port 1
4c. The hold diaphragm 15 is formed of an elastic body, and closes the communication between the input chamber 11 and the output chamber 12.

The decay valve 16 has a valve input port 16a, a valve output port 16b, and a valve exhaust port 16c. A plunger 16e for disconnecting and communicating with each port is disposed in the decay valve 16. The plunger 16e includes the flow path blocking members 16f and 16g.
Are provided at both ends, and the plunger 16e is normally urged downward in the figure by the return spring 16k, and the valve input port 16a and the valve discharge port 16c, and the valve output port 16b and the valve discharge port 16c, while the valve input port 16a and the valve output port 16b are in communication. When the solenoid 16d is energized, the plunger 16e moves upward from the illustrated state,
The valve input port 16a and the valve output port 16b are shut off by the flow path shutoff member 16f, and the valve output port 16a is closed.
b and the valve exhaust port 16c.

The valve input port 16a of the above-described decay valve 16 is connected to the brake valve via the flow path 26 and the one-way valve 25, the valve output port 16b is connected to the rear chamber 17a of the decay diaphragm 17, and the valve exhaust port 16c is connected to the exhaust chamber. 13, and when not in operation, the valve input port 16a and the valve output port 16b
(In other words, the input chamber 11 communicates with the rear chamber 17a of the decay diaphragm 17).
a is cut off from the exhaust chamber 13. When the solenoid 16d of the decay valve 16 is energized and the plunger 16e is moved upward in the drawing, the brake chamber and the rear chamber 17a of the decay diaphragm 17 are shut off, and the rear chamber 17a communicates with the exhaust chamber 13. The decay diaphragm 17 is formed of an elastic body, and is constantly urged by the return spring 17b.
3 is elastically deformed in a direction to close the communication with the third member.

The one-way valve 25 includes a valve body 25a and a spring 25b, and is configured to allow air pressure to flow only from the brake valve to the valve input port 16a.

The operation of the air control valve according to the above configuration will be described. [When the brake pedal is pressed] When the brake pedal is depressed, the brake valve opens, and air according to the depression force of the brake pedal is supplied to the air control valve 10 from the air tank. The air pressure flowing into the input chamber 11 of the air control valve 10 acts on the hold diaphragm 15, moves the hold diaphragm 15 rightward as shown in FIG. 2, and connects the input chamber 11 and the output chamber 12. The air pressure flows from the opened output chamber 12 to the air master cylinder, and operates the brake cylinder to operate the brake in the same manner as in the conventional brake system. At this time, since there is no return spring in the rear chamber 15a of the hold diaphragm, when air pressure acts, the hold diaphragm opens immediately,
Since air pressure can be supplied to the air master cylinder, pressurization response is improved.

When the brake is pressurized, the air pressure also acts on the decay diaphragm 17 from the output chamber 12, but the rear chamber 17a of the decay diaphragm 17 has an input chamber 11, a one-way valve 25, a flow path 26, and a valve of the decay valve 16. Since the air pressure in the input chamber 11 flows through the input port 16a → the valve output port 16b, the decay diaphragm 17 is not opened by the air pressure from the air master cylinder 4. The air pressure flowing into the rear chamber 17a is sealed in the rear chamber 17a until the decay valve 16 is opened by the action of the one-way valve 25, so that the air pressure is reduced every time the brake is pressurized as in the conventional air control valve. No air is supplied to the rear chamber, the consumption of air pressure can be reduced, and the brake pressure response can be improved.

When the brake pedal is released, the high pressure air of the air master cylinder opens the hold diaphragm and is released to the atmosphere from the brake valve.
The brake is released. At this time, the air pressure in the rear chamber 17a of the decay diaphragm 17 is sealed in the rear chamber until the decay valve opens as described above.
The decay diaphragm remains closed.

[At the time of anti-lock operation] At the time of brake operation, anti-lock control is started, and when a command for holding the brake pressure is issued, as shown in FIG. 3, the solenoid 14d of the hold valve 14 is energized, and the plunger 14e operates.
The valve input port 14a and the valve output port 14b of the hold valve 14 are communicated with each other, and the air pressure from the brake valve acts on the rear chamber 15a of the hold diaphragm 15, and the hold diaphragm 15 cuts off the communication between the input chamber 11 and the output chamber 12. Then, the air pressure of the brake device is maintained at the air pressure at that time. At this time, the decay diaphragm is moved by the air pressure in the rear chamber 17a to the input chamber 11 and the exhaust chamber 1
The connection with 3 has been interrupted.

When the brake pressure reducing command is issued, the solenoids of the hold valve 14 and the decay valve 16 are energized to operate the plungers 14e and 16e, as shown in FIG.
In the hold valve 14, a valve input port 14a and a valve output port 14b communicate with each other, and a valve output port 16b of a decay valve 16 and a valve exhaust port 16a.
c is communicated. As a result, the hold diaphragm 15
The air pressure acts on the rear chamber 15a of the decay diaphragm 17, while the air pressure of the rear chamber 17a of the decay diaphragm 17 is released.
, And is exhausted from the exhaust chamber 13 to reduce the brake pressure. Further, the re-pressurization during the antilock control is the same as that of the normal brake. Since the one-way valve 25 is arranged in the flow path 26 communicating with the valve input port 16a of the decay valve 16, it does not affect the operation of the antilock control. In the present embodiment, a one-way valve is disposed in the air control valve, and the communication between the input chamber 111 and the output chamber 112 is closed by the elastic force of the hold diaphragm 115 itself, and a return spring disposed in a rear chamber of the hold diaphragm is provided. Since it is abolished, responsiveness at the time of applying brake pressure can be improved, and generation of abnormal noise can be eliminated.

[0030]

As described above in detail, the present invention provides a one-way air passage that allows air pressure to flow only from the brake valve to the rear chamber of the decay diaphragm in the flow path communicating the brake valve with the rear chamber of the decay diaphragm. Since a valve is provided so that a predetermined air pressure is always contained in the rear chamber at the first time of the brake operation, it is necessary to supply the air pressure to the rear chamber of the decay diaphragm every time the brake is applied as in a conventional air control valve. And the consumption of air pressure after the first time can be reduced,
Brake pressure response can be improved. By enclosing the air pressure in the rear chamber of the decay diaphragm, it is possible to eliminate the vibration and abnormal noise of the decay diaphragm caused by the air pressure difference generated in the decay diaphragm when the brake is depressurized. By confining the pressure, the return spring in the rear chamber of the hold valve can be eliminated, which can further improve the brake responsiveness during pressurization. In addition, the output chamber when the brake is not activated , The residual pressure can be reduced, and so on.

[Brief description of the drawings]

FIG. 1 is a sectional view of the air control valve in a non-operating state.

FIG. 2 is a cross-sectional view showing a state in which a brake is applied to the air control valve.

FIG. 3 is a cross-sectional view showing a state of the air control valve in a holding mode during antilock control.

FIG. 4 is a cross-sectional view showing a state of the air control valve in a pressure reduction mode during antilock control.

FIG. 5 is a cross-sectional view of a conventional air control valve disposed in a brake system.

[Explanation of symbols]

 Reference Signs List 10 air control valve 11 input chamber 12 output chamber 13 exhaust chamber 14 hold valve 15 hold diaphragm 16 decay valve 17 decay diaphragm 25 one-way valve 25a valve body 25b spring 26 flow path

Claims (2)

[Claims] 1. A brake valve, which is disposed between a brake valve and an air master cylinder for applying a brake to a wheel by the action of air pressure fed from the brake valve, wherein the air pressure fed from the brake valve is transmitted to the air master cylinder. An air control valve (10) comprising a hold diaphragm (15) and a decay diaphragm (17) which selectively communicates with a master cylinder or operates to reduce the pressure of the air pressure communicated therewith, wherein a rear chamber of the decay diaphragm and a brake valve are provided. 2 that communicates with
6, a one-way valve 25 is provided for allowing air pressure to flow from the brake valve to the rear chamber of the decay diaphragm, so that a predetermined air pressure is sealed in the rear chamber 17a when a brake is operated. Air control valve. 2. The air control valve according to claim 1, wherein the hold diaphragm is formed of an elastic body, and communication between the brake valve and the air master cylinder is interrupted by an elastic force of the hold diaphragm. .