JPH0736136B2 - Bidirectional pressure reducing valve - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a bidirectional pressure reducing valve used for pneumatic equipment.

[Prior Art] Various pressure reducing valves are used in pneumatic equipment, but in many of them, a supply side (input side) port and a discharge side (output side) port of compressed air are predetermined, and Only the pressure reduction control from one side to the output side was possible.

[Problems to be Solved by the Invention] Since the input port and the output port are defined in the conventional pressure reducing valve, for example, the compressed air is charged into the pressure vessel or the compressed air is discharged from the pressure vessel. When it is necessary to control both the filling pressure and the discharge pressure, it is necessary to separately provide pressure reducing valves for the filling and the discharging, respectively. There is a problem. In addition, it is necessary to connect the supply pipe to the input side port and the discharge pipe to the output side port without mistake during piping work.If they are connected incorrectly, it will not serve as a pressure reducing valve, so the piping work will have to be redone. Take the trouble. There are some that change the diameter of the input side and the output side or the pitch of the screw so that incorrect piping can not be done, but it is not only troublesome to manufacture, but it is necessary to prepare different piping corresponding to it. There is inconvenience.

The present invention has been made in view of the above problems,
It is an object of the present invention to provide a bidirectional pressure reducing valve that does not clearly distinguish the two ports into an input side and an output side and can perform pressure reduction control regardless of the direction in which compressed air flows.

[Means for Solving the Problems] In order to achieve the above object, in the present invention, two chambers having one input / output port and communicating with each other, a pilot chamber and a balance defined by a diaphragm are provided. A valve body which is operated by pressure opposition in the room to control the communication state of the two chambers, an adjusting means for adjusting the pilot pressure, a passage for communicating the chambers with the balance chamber, the chambers and the chambers. And a switching means for switching the state of communication with the balance chamber.

Further, in the invention according to the second aspect, in the switching means, the spool is provided in the housing so as to be slidable in the longitudinal direction thereof, and the passages for supplying the pressures of the respective chambers are formed on different end face sides of the spool. When the pressure in one chamber is higher than the pressure in the other chamber, the spool is placed in a position to bring the other chamber into communication with the balance chamber, and when the pressure in the other chamber is higher than the pressure in the one chamber, the spool It is arranged so that one chamber communicates with the balance chamber.

[Operation] With the above-described configuration, in the pressure reducing valve of the present invention, two input / output ports are connected to the pipeline without distinction between the supply (input) side and the discharge (output) side. Then, the chamber corresponding to the input / output port connected to the discharge (output) side pipeline is communicated with the balance chamber by the action of the switching means. Therefore, the pressure on the discharge (output) side is supplied to the balance chamber, and the valve body is actuated via the diaphragm against the pressure in the pilot chamber to perform a predetermined decompression operation.

Further, in the invention according to the second aspect, when the compressed air is supplied to the pressure reducing valve in a state where the two input / output ports are connected to the pipeline without distinction between the supply (input) side and the discharge (output) side. , The spool constituting the switching means is automatically connected to the output side by the balance between the room pressure on the input / output port side connected to the supply side and the room pressure on the input / output port side connected to the discharge side. It is placed at a position where it communicates with the balance chamber on the input / output port side. Then, the pressure on the discharge (output) side is supplied to the balance chamber, and the valve body is actuated via the diaphragm against the pressure in the pilot chamber to perform a predetermined depressurizing operation.

[First Embodiment] A first embodiment in which the present invention is embodied in a pilot type pressure control valve using a nozzle flapper mechanism will be described below with reference to FIGS.

At the center of the lower part of the valve housing 1, two chambers 2 and 3 are vertically arranged so as to communicate with each other, and each chamber 2 and 3 is provided with one input / output port 2a and 3a, respectively. A valve seat 4 is formed at the lower end of the one chamber 2. Also, one chamber 2
A chamber communicating with the chamber 2 is formed above, and the chamber is divided into upper and lower three stages by the upper portions of the two diaphragms 5 and 6 and the supporting member 7 supported by the diaphragms 5 and 6,
A pilot chamber 8, a first balance chamber 9 and a second balance chamber 10 are formed. The support member 7 is formed so as to extend through the chamber 2, a spool 11 for partitioning the chamber 2 and the second balance chamber 10 is integrally formed in an intermediate portion of the support member 7, and the valve seat is formed at a lower end thereof. A valve body 12 that can abut against 4 is fitted and fixed. The air pressure in chambers 2 and 3 is directly
The pressure receiving areas of the spool 11 and the valve body 12 are formed to be equal to each other so as not to affect the movement of the. Further, a bias spring 10a is provided in the second balance chamber 10.

In order to connect the chambers 2 and 3 to the first balance chamber 9 in the valve housing 1, passages 13 and 14 having one end open to the chambers 2 and 3 and the other end opening to the outside of the valve housing 1 and one end The first balance chamber 9 is formed with a passage 15 whose other end opens to the outside of the valve housing 1. A switching valve 16 is disposed outside the valve housing 1 at a position corresponding to the opening of each of the passages 13 to 15 as switching means for switching the communication state between the chambers 2 and 3 and the first balance chamber 9. Has been done. The housing 17 of the switching valve 16 has a housing portion in which a spool 18 is slidably housed in the longitudinal direction thereof and the passages 13 to
Ports 17a to 17c communicating with 15 are formed, and
A passage 19 for supplying the pressure of each chamber 2, 3 to the end face side of the spool 18.
a and 19b are formed. And the spool 18 is the passage 19
The ports 17a to 17c are slid by the pressure supplied from a and 19b, and the communication state of the ports 17a to 17c is blocked at the neutral position. At the moved position, the ports 17b and 17c are formed to communicate with each other.

Pilot pressure is supplied to the pilot chamber 8 from a pilot pressure supply passage 21 having an orifice 20. A nozzle flapper mechanism as an adjusting means for adjusting the pilot pressure is provided above the pilot chamber 8, and the nozzle flapper mechanism is composed of a nozzle 22 and a piezoelectric element flapper 23 that faces the nozzle 22 and adjusts the opening. . For the piezoelectric element flapper 23, a so-called piezo bimorph in which piezoelectric elements are adhered to both sides of a thin metal plate is used, and displacement is caused by an applied voltage to operate a nozzle opening and control pilot pressure. . The piezoelectric element flapper 23 is controlled by a controller 25 which controls an applied voltage based on an output signal from a pressure sensor 24 provided at a branch portion of the passage 15 and a setting signal.

Next, the operation of the pilot type pressure control valve configured as described above will be described. When connecting this pilot type pressure control valve to the pipeline, supply (input) side of the pipeline, discharge (output)
Both input / output ports 2a and 3a are connected to the pipeline without considering the side.

First, the case where the input / output port 2a of the one chamber 2 is connected to the supply-side pipeline and the input / output port 3a of the other chamber 3 is connected to the discharge-side pipeline will be described. When the compressed air is not supplied from the pipe, the spool 18 of the switching valve 16 is arranged in the neutral position. When the pressure of the input / output port 2a is Pa and the pressure of the input / output port 3a is Pb, the pressure of the input / output port 2a connected to the supply side when compressed air is supplied from the pipeline
Pa becomes larger than the pressure Pb of the input / output port 3a connected to the discharge side, and the spool 18 is moved from the neutral position to the position shown in FIG. As a result, the ports 17b and 17c of the switching valve 16 are brought into communication with each other, and the input / output port 3a connected to the discharge side and the first balance chamber 9 pass through the passage 14, the ports 17c, 17b, and the passage 15. Connected, input / output port 3a
The pressure Pb is transmitted to the first balance chamber 9 and the pressure sensor 24.

In this state, the controller 25 compares the setting signal with the feedback signal from the pressure sensor 24 and compares the setting signal with the piezoelectric element flapper 23.
When the set signal is larger than the feedback signal (pressure signal corresponding to the pressure Pb of the input / output port 3a), the voltage applied to the piezoelectric element flapper 23 increases and the piezoelectric element flapper increases. The tip of 23 is displaced downward and tries to close the nozzle opening. Here, the compressed air supplied from the pilot pressure supply port 21a is the orifice 2
Although it passes through 0 and flows into the pilot chamber 8, the pressure in the pilot chamber 8 rises because the nozzle opening is closed by the piezoelectric element flapper 23, and the diaphragms 5 and 6 are supported by the support member 7
At the same time, the valve body 12 is pushed down to open the valve body 12, and the compressed air supplied to the input / output port 2a connected to the supply side is supplied to the input / output port 3a connected to the discharge side. When the pressure in the I / O port 3a rises, two diaphragms
The pressure between 5 and 6, that is, the pressure in the first balance chamber 9 also rises, the feedback signal from the pressure sensor 24 increases, and the difference from the set signal decreases, and the piezoelectric element flapper 23
Is reduced, the opening of the nozzle 22 is opened, and the pilot pressure is reduced, so that the valve body 12 is closed. In this way, the decompression control of the compressed air supplied from the input / output port 2a connected to the supply side to the input / output port 3a connected to the discharge side is performed.

On the other hand, when the input / output port 2a of the one chamber 2 is connected to the discharge side pipeline and the input / output port 3a of the other chamber 3 is connected to the input side pipeline during the connection work to the piping, On the contrary to the above, the pressure Pa of the input / output port 2a is the pressure Pb of the input / output port 3a.
It becomes smaller, and the spool 18 of the switching valve 16 is pushed up from the neutral position to the state shown in FIG. As a result, the ports 17a and 17b of the switching valve 16 are brought into communication with each other, and the input / output port 2a connected to the discharge side and the first balance chamber 9 are passed through the passage 13, the ports 17a, 17b, and the passage 15. The pressure Pa of the input / output port 2a is communicated with the first balance chamber 9 and the pressure sensor 24. Then, the pressure signal fed back to the controller 25 from the pressure sensor 24 corresponds to the pressure Pa of the input / output port 2a, and the valve flap 12 is operated by the nozzle flapper mechanism in the same manner as described above.
Is operated, and the decompression control of the compressed air supplied from the input / output port 3a connected to the supply side to the input / output port 2a connected to the discharge side is performed.

[Second Embodiment] Next, a second embodiment will be described with reference to FIG. In this embodiment, instead of adopting the nozzle flapper mechanism as the adjusting means for adjusting the pilot pressure, the pressure adjusting spring 27 capable of adjusting the pressing force on the supporting member 7 by operating the manual knob 26 is used. It is largely different from the example, and other configurations are basically the same. A manual knob 26 is rotatably attached to the upper portion of the valve housing 1, and a pressure adjusting screw 28 is integrally rotatably fixed to the manual knob 26. A stop ring 29 is screwed onto the pressure adjusting screw 28, and the pressure adjusting spring 27 is interposed between the stop ring 29 and the support member 7. The stop ring 29 moves along with the turning operation of the manual knob 26 so that the pressure adjusting screw 28
Along with, the distance between the stop ring 29 and the support member 7 changes, and the pressing force of the pressure adjusting spring 27 is changed.

Therefore, also in the pressure reducing valve of this embodiment, the spool 18 of the switching valve 16 has the input / output port connected to the discharge side of both the input / output ports 2a and 3a as the first balance chamber 9 as in the above-described embodiment. It is automatically placed in a position where it communicates with each other, and the opening of the valve body 12 is determined by the opposition of the pressing force of the pressure adjusting spring 27 and the pressure of the input / output port connected to the discharge side, and it is connected to the supply side. The decompression control of the compressed air supplied from the input / output port to the input / output port connected to the discharge side is performed.

The present invention is not limited to the above embodiment,
For example, as shown in FIG. 4, an electromagnetic valve 30 may be provided as a switching means to electrically switch the control direction, or the switching valve 16 and the electromagnetic valve 30 may be incorporated in the valve housing 1. Further, a manual switching valve may be adopted as the switching means.

[Effects of the Invention] As described in detail above, according to the present invention, the pressure reduction control can be performed on the flow from either side of the two input / output ports by the action of the switching means. Even if the two input / output ports are connected to the pipeline without distinction between the supply (input) side and the discharge (output) side, the output (input / output) side input / output ports become the balance chamber due to the action of the switching means. The valve element is operated via the diaphragm in communication with the pressure in the pilot chamber,
Since the compressed air supplied from the supply-side input / output port to the discharge-side input / output port is depressurized, it is possible to work without worrying about the mounting direction of the input / output port during piping work.

Further, in the invention according to the second aspect, the spool constituting the switching means is arranged at a position where the chamber on the input / output port side, which is automatically connected to the discharge (output) side, communicates with the balance chamber, and the discharge (output) is performed. ) Side pressure is supplied to the balance chamber, and the valve body is actuated via the diaphragm against the pressure in the pilot chamber to perform a predetermined pressure reducing operation.

[Brief description of drawings]

1 and 2 are sectional views of a first embodiment embodying the present invention,
FIG. 3 is a sectional view of the second embodiment, and FIG. 4 is a sectional view of a modified example. Chambers 2, 3, input / output ports 2a, 3a, diaphragms 5, 6, pilot chamber 8, first balance chamber 9, second balance chamber 10,
Valve body 12, passages 13, 14, 15, switching valve 16 as switching means, solenoid valve 30, spool 18, pilot pressure supply passage 21, nozzle 22 constituting pilot pressure adjusting means, piezoelectric element flapper 23, pressure sensor 24 Similarly, a manual knob 26, a pressure adjusting spring 27, and a pressure adjusting screw 28 which constitute pilot pressure adjusting means.

Claims (2)

[Claims] 1. A pilot chamber (8) defined by two chambers (2,3) having one input / output port (2a, 3a) and communicating with each other, and a diaphragm (5,6). And a valve element (12) which is actuated by counteracting the pressure in the balance chamber (9) to control the communication state of the two chambers (2, 3)
Adjusting means (22,23,24, etc.) for adjusting pilot pressure, passages (13,14,15) for communicating the chambers (2,3) with the balance chamber (9), A two-way pressure reducing valve comprising: switching means (16, 30) for switching the communication state between each chamber (2, 3) and the balance chamber (9). 2. A housing (17) for the switching means (16).
A spool (18) is slidably provided inside the chamber (2, 3) on the different end faces of the spool (18).
Passages (19a, 19b) for supplying the respective pressures of the two chambers are formed, and when the pressure of one chamber (2) is higher than the pressure of the other chamber (3), the spool (18) balances the other chamber (3). The chamber (9) is placed in communication with the other chamber (3)
The spool according to claim 1, wherein the spool (18) is arranged at a position for communicating one chamber (2) with the balance chamber (9) when the pressure in the chamber is higher than the pressure in the one chamber (2). Directional pressure reducing valve.