JPH066423B2 - Pressurizing-proportional valve device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pressure proportioning valve, and in particular, it produces an output pressure that exactly matches an input pressure or a control pressure up to a predetermined pressure value, but a control pressure higher than that produces a pressure output corresponding to the control pressure. The present invention relates to a pressure proportioning valve device having a characteristic of generating a variable controllable output pressure.

Such a proportioning valve is particularly suitable for controlling a vehicle fluid pressure brake system which controls the brake pressure in response to the vehicle load.

British Patent No. 1,585,108 discloses a pressure proportioning valve for controlling brake pressure, especially in response to variable loads, in which a return spring in a brake mechanism is activated when the brake is actuated. In order to overcome the resistance, the output pressure follows the control pressure up to a given pressure value, above which the valve starts to proportion the output depending on the load setting. To perform this action, the pressure responsive member of the proportioning valve is operated through the in-shot valve with a resistance pressure up to a given value. Further, the in-shot valve is designed to gradually reduce the in-shot pressure over the operating range of the proportioning valve output pressure so as not to adversely affect the proportioning valve's ratio, especially its low load setting ratio.

An object of the present invention is to provide a simpler device which generates an initial output pressure corresponding to an input pressure up to a predetermined value, but generates an output pressure according to a variable setting when the initial output pressure is exceeded.

To this end, according to the invention, there is provided an actuator for actuating an overlapping double valve assembly cooperating with a variable area pressure responder and its control member, said pressure responder comprising a pressure source. Receives the fluid pressure from the input port or the control port that controls the valve of the valve assembly in the opening direction between the input port and the output port of the valve assembly and the valve of the valve assembly between the output port and the vent. In a pressure proportioning valve device that receives fluid pressure at an output port in a direction opposite to the direction of opening the double valve actuating device, the double valve actuating device can further operate at a pressure equal to or higher than a predetermined pressure corresponding to a given input output pressure value, A fluid pressure responsive device for adjusting the position of the actuator with respect to the variable area pressure responsive device that causes the double valve to overlap, toward a position set by the control member; Causes the pressure at the output port to match the rising pressure curve at the input port up to the predetermined pressure value obtained by gradual adjustment, and when it exceeds that value, it is balanced by the relative area of the area variable type pressure response member set by the control member. A pressure proportioning valve device is provided.

In order that the present invention may be better understood and easily implemented, the present invention will now be described by way of example with reference to the accompanying drawings.

Referring to FIG. 1, the pressure proportioning valve arrangement shown herein is designed for use as a load-responsive valve in a brake system that can be operated with fluid pressure. This valve device has upper and lower bodies, respectively designated by the reference numerals 1 and 2, which are bolted together so as to clamp the periphery 3 of the effective area variable diaphragm 4, the central edge 5 of said diaphragm 4 being the piston 7. Held in a groove 6 formed in the skirt of the piston, the piston 7 is provided with a seal 35 that can slide in the cylindrical bore 8 of the upper body 1. The piston 7 carries a double valve member 9, which is spring-loaded downwards by a spring 10 towards an input valve seat 11 formed on the annular flange of the piston 7. A tubular vent valve member 12 is provided which projects upwards from the lower part of the piston 7 towards the double valve member 9, which vent valve member 12 is in the lower part of the housing or lower body 2
It is possible to slide in a sealed manner in the hole 13 formed in the. The piston 7 is guided by the seal 35 and the non-sealing guide member 34, and the lower side of the diaphragm 4 communicates with the output port 15.

The lower part of the housing connects the output port 15 of the valve device to the ventilation part 1.
It has a dividing wall 14 separating from 6. The tubular vent valve member 12 has a downward extension 17, and a spring 19 is held between the lower surface of the extension 17 and the piston 18. The slidable member 12, its downward extension 17 and other parts form the fluid pressure responsive actuator of the dual valve assembly. The piston 18 slides in the cylinder, but its lower end 20 communicates with the input port 22 of the valve device via the pipe 21, and the input pressure is transmitted from this input port 22 to the upper part of the piston 7. The piston 18 has a shaft portion 23 extending upward.
And a top surface 24 of which has a control lever 26 pivotally mounted.
Can be engaged with the spherical end 25 of said housing and said lever 26 can be operated by an external lever 28 via a bearing 27 in the casing. The spherical end 25 corresponds to the surface 24 and the vent valve member 1
It is installed between the two inner protruding portions 29.

Referring to the effective area variable type diaphragm 4, this diaphragm 4 is of a generally known type and includes a piston 7
With the radially outwardly extending fingers 31, which are arranged to alternate with inwardly extending fingers 32 of an annular member provided inside the upper body 1. . The downward faces of the fingers 31 and 32 are formed at an angle to each other, and when the piston 7 moves downward from the position shown, the effective area of the diaphragm 4 against the pressure of the output port acting on the lower side of the diaphragm 4 increases. On the other hand, the upper part of the diaphragm 4 is ventilated through the opening 33.

The operation of the pressure proportioning valve arrangement when there is no pressure at the input port 22 and the vehicle is unloaded will now be described with the lever 28 in the illustrated position (for example) and the valve assembly substantially at the first position. In the condition shown, the piston 18 has its stop member 37
The vent valve member 12 is urged against the stop member 36 by the spring 19. When the input pressure of the input port 22 starts to increase due to the operation of the brake valve of the vehicle and the pressure slightly increases, the piston 7 causes the valve member 9 to move to the exhaust valve member 12
The valve member 9 moves away from the valve seat 11 by moving it slightly downward so that the valve member 9 is seated on the valve seat 11. In this way, the input air pressure is transmitted to the output port 15 via the valve member 9 which is released, and the diaphragm 4
Acts friendly to the underside of. Due to the action of the spring 19, the tubular vent valve member 12 is held exactly in the position shown over the first part of this characteristic curve irrespective of the setting of the lever 28. Therefore, the output pressure is initially a third pressure so as to form a starting pressure for the brake actuator.
Up to a predetermined input pressure of the input port 22 shown by P ₁ in the figure, the input pressure is directly followed regardless of the setting of the lever 28.

When this downwardly acting pressure at the input port 22 reaches a predetermined input pressure, the vent valve member 12, and thus the piston 7
Begins to move downwards against the action of spring 19. At the same time, the input pressure exerted on the portion 20 via the pipe 21 acts on the underside of the piston 18 in a direction that raises the piston 18 against the action of the spring 19. This action is
By increasing the upward force transmitted to the vent valve member 12 by the spring 19 and preventing downward movement of the vent valve member 12, a balanced condition is maintained and no movement occurs.

However, if the input pressure continues to rise, the piston 7,
The double valve valve member 9 and the vent valve member 12 gradually move downwards and the piston 18 continues to rise. In this way, the effective area of the diaphragm 4 gradually increases, and the output pressure gradually increases at a constant rate. This action is the third
At a second predetermined input pressure, shown at P ₂ in the figure, the projection 29 of the vent valve member 12 contacts the spherical end 25 to prevent further downward movement, thereby setting the desired lever position. Until the balance of is achieved.

At a certain input pressure, for example equal to the pressure P ₃ , the input pressure further increases and depends on the position of the spherical end 25,
The shaft portion 23 of the piston 18 contacts the lower edge of the spherical end 25,
The spherical end 25 is sandwiched between the surface 24 and the protrusion 29. Therefore, when the input pressure exceeds P ₃ , the downward synthetic force transmitted by the ventilation valve member 12 via the lever 26 causes
Overpressure is prevented from being transmitted to the lever 28.

The subsequent decrease in input pressure is represented by the curve shown by the broken line in FIG. Due to this pressure decrease, the piston 7 rises and separates the valve member 9 from the vent valve member 12 at the supply pressure P ₄ , and vents the lower part of the diaphragm 4 to the vent portion 16.

When the delivery pressure decreases to approximately P ₂ , the vent valve member 12 lifts the piston 7 and begins to reduce the effective area of the diaphragm 4. As a result, the balance of the brake pressure is reduced until the vent valve member 12 contacts the stop member 36 of the main body 2, the effective area of the diaphragm 4 is minimized, and the output pressure of the output port 15 is input to the input port 22. Equals pressure. This condition continues until both the input pressure and the delivery pressure are completely vented.

As is apparent from the above, the pressure responsive device in the form of the vent valve member 12 modifies the position of the piston 7 which causes double valve overlap in response to the input pressure of a given level, so that the pressure at the output port is adjusted. Follows the pressure of the input port up to the given pressure value,
Above that value, the output to input is balanced according to the adjustable ratio set by the valve.

Referring now to FIG. 2, this figure shows another type of pressure proportioning valve in the form of a device designed to operate as a variable actuation relay valve. This device has a housing part of an upper part 41 and a lower part 42, the output port 62 of the lower part 42 of this housing being similar to the diaphragm 4 of FIG. 1 and the underside of a diaphragm 43 clamped between the two housing parts. I understand. A skirt 45 of a piston 44 is supported concentrically with the diaphragm 43, and this piston 44 can slide in a cylindrical hole 46 in the upper part 41 of the housing, the upper surface of which is the control pressure port 4
I am familiar with 7. A pressure responsive member in the form of a smaller piston 48 is sealingly slidable within the skirt 45 and carries a downwardly projecting vent valve member 49 which cooperates with a movable dual valve assembly carried by the lower portion 42 of the housing. ing. The piston 48 is a spring 50 provided in the piston 44.
Loaded by the adjusting screw 51
Can be adjusted by. Further, the ventilation passage 52
Is formed near the adjusting screw 51. Piston 48
The vent valve member 49 constitutes a pressure-responsive actuating device of the dual valve assembly.

Referring next to the dual valve assembly, the assembly is supported by a hermetically slidable plunger 53 and has a weak spring 55.
The double valve member 54 which is pressed by the input valve seat 56 by the
The communication with the input valve seat 56 is performed from the input port or the reservoir port 58 through the opening 57. Although not shown, the plunger 53 includes a device for adjusting the vertical position of its shaft 59 to adjust the valve assembly ratio. In addition, two small passages 60, 61 are provided for the purpose of balancing the pressure of the self-overlapping valve device so that the pressure below the diaphragm 43 communicates with the annular part 63 acting upwards on the double valve. ing.

In the operation of the pressure proportioning valve of FIG. 2, when the control pressure initially applied to the input port 47 is zero, the double valve is stationary and the lower end of the adjusting screw 51 reaches the valve member 54. The valve member 54 is in contact with the input valve seat 56. This state is the spring 50,
It is obtained by the action of 55. When the input pressure begins to rise, the pressure acts on the piston 44, and when the piston 44 overcomes the force of the weak spring 55, the double valve member 54 causes the valve seat 5 to move.
6, the air under pressure is supplied from the pressure source through the input port 58 to the output port 62 and the lower side of the diaphragm 43. When the predetermined pressure reaches, for example, 0.7 bar, the spring 50 starts to respond to the movement of the piston 48 by the action of the fluid pressure at the output port 62, and the piston 48 gradually moves toward the upper stop member of the piston 44 as the input pressure increases. Move, so that the diaphragm assembly moves to piston 4
4 works downward to balance the input pressure above 4 with the output pressure below diaphragm 43, in which case the double valves overlap and both valve seats are closed.

Thus, as is apparent, the position of the pressure responsive actuator that causes the double valve overlap is adjusted by the piston 48 and spring 50 to reach a predetermined pressure so that the output pressure tracks the input pressure up to this value. Supply sufficient operating pressure to the brake actuator, above which the lower plunger 53 and valve assembly are positioned in response to the vehicle load, causing the device to adjust the output pressure and the control pressure according to their settings. Make a balance.

As can be seen from FIGS. 1 and 2, another embodiment of the invention is readily conceivable and the device is a direct pressure proportioning valve or a pressure relay valve. It will be further appreciated that the pressure corresponding to the control pressure to which another pressure responsive device responds is the control pressure itself as in FIG. 1 or the delivery pressure or other pressure as in FIG. be able to.

[Brief description of drawings]

1 is a vertical sectional view of a pressure proportioning valve device according to a first embodiment of the present invention, FIG. 2 is a vertical sectional view of a pressure proportioning valve device according to a second embodiment, and FIG. The operating characteristics are shown. 4, 43: diaphragm, 8: cylindrical hole, 9: double valve member, 10: spring, 11, 56: input valve seat, 12, 49:
Ventilation valve member, 15, 62: output port, 17: downward extension part,
18, 48: Piston, 19, 50, 55: Spring, 2
2, 58: input port, 25: spherical end, 28: external lever,
31: finger, 32: finger, 47: control pressure port,
54: double valve member, 59: shaft portion, P ₁ : predetermined pressure

Claims (8)

[Claims] 1. An area variable type pressure response device (4, 31, 3)
2; 43) and its control member (28; 59) cooperating dual valve assembly (7,9,10,11; 5).
4,55,56) actuating device (12,17,1)
8, 19; 48, 49), wherein the pressure responsive device has an input port (22; 58) and an output port (15; 6) from a pressure source.
2) receives the fluid pressure from the input port or the control pressure port (22, 47) for controlling the valve of the valve assembly in the opening direction, and outputs (15, 62) and the vent (16;
59) in a pressure proportioning valve arrangement which receives fluid pressure at the output port in a direction opposite to the direction in which the valve of the valve assembly is opened, said double valve actuating device (12, 17, 18, 19; 48, 49) further controls the position of the actuating device relative to the variable area pressure responsive device capable of actuating above a predetermined pressure corresponding to a given input pressure value and causing the double valve overlap, the control member (28 59) has a fluid pressure response device (18, 19; 48, 50) for adjusting toward the position set by the input port up to the predetermined pressure obtained by gradual adjustment of the pressure at the output port. Corresponding to the rising pressure curve of
A pressure proportioning valve device characterized in that, when the value exceeds that value, the pressure proportional member is balanced by the relative area of the area variable type pressure responsive member set by the control member (28; 59). 2. The pressure proportioning device according to claim 1, wherein the variable area pressure responding device has an area invariant portion that receives the pressure of the input port and an opposing variable area portion that receives the pressure of the output port. Valve device. 3. A dual valve assembly is supported by a variable area pressure responsive device, and the actuating device of the dual valve assembly is a pressing device (19).
3. The pressure proportioning valve device according to claim 2, further comprising a ventilation valve member (12) which is pressed against the action of the pressure of the output port. 4. A pressure-responsive piston (18) which can be operated at a pressure above a predetermined pressure so as to overcome the pressing device (19) and which connects between the control member (28) and the operating device (17).
The pressure proportioning valve device according to claim 3, further comprising: 5. A dual valve assembly (54,55,56) supported on a movable member (53), an actuator (48,50) supported on a variable area pressure responder, and a push piston (48). A vent valve member (49) supported by
The pressure proportioning valve device according to claim 1, wherein the piston (48) is movable in the variable area pressure responsive device by the action of a fluid pressure higher than a predetermined pressure at the output port. 6. The double valve assembly (54, 55, 56) has a passageway (57) through which fluid pressure can be input independently of the control pressure port (47). The pressure proportioning valve device according to claim 5, which is supplied from 7. The pressure proportioning valve device according to claim 5, wherein the movable member (53) can be moved by the control device (59) with respect to the variable area pressure responsive device. . 8. A pressure proportioning valve device according to claim 1, further comprising a device (51) for adjusting a predetermined pressure.