JP2003108235A - Adjustment apparatus for fluid pressure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a suitable use of an adjustment apparatus in environment such as a clean-room required cleanliness. SOLUTION: An adjustment apparatus for fluid pressure comprises a ventilation valve 30 displacing under pilot pressure supplied into a pilot room 52, a valve spring 36 pressing the valve 30 toward a seating part 38 and a covering material 40 provided in a connecting path to seal the valve 30 and spring 36 against pressured fluid flowing in the connecting path by shielding the valve 30 and spring 36.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention can supply a regulated pressure fluid to a fluid pressure device such as a cylinder, and is preferably used in an environment where cleanliness is required such as a clean room. The present invention relates to a fluid pressure adjusting device capable of performing.

[0002]

2. Description of the Related Art Generally, when a pressure fluid is supplied from a fluid pressure supply source to a fluid pressure device at a desired set pressure, a fluid pressure adjusting device is interposed between the fluid pressure supply source and the fluid pressure device. . This fluid pressure adjusting device reduces the pressure fluid on the primary side supplied from a fluid pressure supply source to a desired pressure so as to correspond to a fluid pressure device connected to the secondary side and supplies the fluid to the secondary side. It is a thing.

As a fluid pressure adjusting device according to this type of conventional technique, for example, a pressure control valve is disclosed in Japanese Patent No. 2589424. As shown in FIG. 3, the pressure control valve 1 has a valve housing 4 in which an air supply port 3a and an output port 3b are formed at both ends of a flow path 2, and the air supply port 3a and the output port 3a are provided. A main valve 5 that regulates the pressure fluid on the primary side supplied from a pressure fluid supply source (not shown) is provided between the main valve 5 and 3b.

In this case, the pilot pressure supplied into the diaphragm chamber 7 by the air supply solenoid valve 6a and the exhaust solenoid valve 6b and the spring force of the spring member 8 for pressing the main valve 5 upward are balanced. By doing so, the valve opening of the main valve 5 is controlled. Solenoid valve 6a for air supply
The exhaust solenoid valve 6b is on / off controlled by control signals output from a control circuit (not shown). The secondary side pressure fluid regulated by the main valve 5 is supplied to a fluid pressure device (not shown) through the output port 3b.

[0005]

However, when the pressure control valve according to the prior art described above is used in an environment where cleanliness is required, such as in a clean room, the sliding portion of the spring member that presses the main valve. As a result, dust such as metal powder and abrasion powder is generated, and the dust is mixed in the fluid flowing through the fluid passage and contaminates the fluid.

The present invention has been made in view of the above problems, and prevents dust and the like generated due to the displacement of the valve body facing the fluid passage from flowing out mixedly in the pressure fluid,
An object of the present invention is to provide a fluid pressure adjusting device that can be suitably used in an environment where cleanliness such as a clean room is required.

[0007]

In order to achieve the above-mentioned object, the present invention is a fluid pressure adjusting device for supplying a predetermined fluid pressure adjusted to a reduced pressure to a fluid pressure device operated by the fluid pressure. And a housing provided with a supply port into which the pressure fluid is introduced, a pressure adjusting port for leading out the pressure fluid whose pressure has been adjusted to be reduced, and a fluid passage for communicating the supply port with the pressure adjusting port, respectively. A valve element that is provided inside the housing so as to be displaceable along the axial direction under the action of a pilot pressure, and that is seated in a seating portion to block communication between the supply port and the pressure adjustment port, A spring member that presses the valve body toward the seating portion; and a sealing unit that shields the valve body and the spring member to seal against the pressure fluid flowing through the fluid passage. Characterized in that it obtain.

In this case, the sealing means is constituted by a covering member that shields the recess of the housing in which the valve body and the spring member are arranged, so that the pressure fluid is prevented from entering the valve body and the spring member. It is suitable.

It is preferable that the covering member is formed of a flexible member, and a part of the valve body is covered so that the covering member can be flexibly bent according to the displacement of the valve body.

According to the present invention, the valve body and the spring member are shielded by the sealing means, and the valve body and the spring member are sealed from the pressure fluid flowing through the fluid passage. Therefore, even if dust such as metal powder or abrasion powder is generated by the sliding portion of the spring member, the dust is shielded by the sealing means, and the dust is prevented from being mixed in the pressure fluid flowing through the fluid passage.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A preferred embodiment of a fluid pressure adjusting device according to the present invention will be described below in detail with reference to the accompanying drawings.

In FIG. 1, reference numeral 10 indicates a fluid pressure adjusting device according to an embodiment of the present invention.

The fluid pressure adjusting device 10 basically has a body portion 14 in which a first block 12a, a second block 12b and a closing block 12c are integrally connected.
And a cover member 1 connected to the upper portion of the body portion 14.
6 and 6. The body portion 14 and the cover member 16 function as a housing.

In the first block 12a of the body portion 14,
Supply port 18 connected to a pressure fluid supply source (not shown)
And a pressure adjusting port 20 connected to a fluid pressure device (for example, a cylinder) (not shown) are formed coaxially with a predetermined distance therebetween. A communication passage (fluid passage) 22 that connects the supply port 18 and the pressure adjusting port 20 is formed between the supply port 18 and the pressure adjusting port 20.

A closing block 12c is connected to a lower side of the body portion 14, a concave portion 24 is formed in a substantially central portion of the closing block 12c, and an annular portion 28 having a through hole 26 is formed in the concave portion 24. It is provided. The through hole 26
A rod portion 32 of an air supply valve (valve body) 30, which will be described later, is slidably provided along the vertical direction.

An annular recess 34 adjacent to the annular portion 28 is formed in the closing block 12c. One end of the annular recess 34 is engaged with the flange portion of the air supply valve 30 and the other end thereof is attached. A valve spring (spring member) 36 is attached to the wall surface of the annular recess 34. In this case, due to the spring force of the valve spring 36, the air supply valve 30 always keeps the seat 38.
It is in a state of being pressed upward so as to be seated on. In addition, the lower end portion of the through hole 26 has a closed block 1
It is closed by a cap member 39 attached to the bottom surface of 2c.

The head portion 30a of the air supply valve 30 is covered with a flexible covering member (sealing means) 40,
The edge portion of the covering member 40 is fixed to the inner wall surface of the communication passage 22. By closing the recess 24 of the closing block 12c with the covering member 40, the air supply valve 30 and the valve spring 36 arranged in the recess 24 are blocked from the communication passage 22.

That is, the covering member 40 is, for example,
From a double structure in which a first diaphragm 42a made of a resin material such as polytetrafluoroethylene (PTFE) and a second diaphragm 42b made of a rubber material such as NBR are integrally connected. In addition, the air supply valve 30 bends in response to the displacement of the air supply valve 30 and also has a sealing function of preventing the pressure fluid flowing through the communication passage 22 from entering the recess 24 side of the closing block 12c.

Therefore, dust such as metal powder and abrasion powder generated in the sliding portion of the valve spring 36 which expands and contracts with the displacement of the air supply valve 30 is sealed by the covering member 40, and the dust is connected to the communication passage 22. The mixture is prevented from being mixed with the pressure fluid flowing through and flowing out.

A chamber 46 communicating with the atmosphere via an exhaust port 44 is formed in a substantially central portion of the body portion 14, and the chamber 46 has a long stem 48 extending in the vertical direction.
Is provided. One end of the stem 48 has an air supply valve 30.
Is provided so as to abut the upper part of.

In this case, the air supply valve 30 has a valve spring 36.
Seated on the seat 38 under the action of the spring force of the supply port 1
8 is in a valve closed state in which the communication between the pressure regulating port 20 and the pressure regulating port 20 is cut off, while the stem 48 presses the air supply valve 30 downward against the spring force of the valve spring 36, whereby the covering member is formed. The air supply valve 30 covered by 40 is separated from the seat portion 38, and the supply port 18 and the pressure adjusting port 20 are in a valve open state in which they communicate with each other via the communication passage 22.

A diaphragm 50 having an outer peripheral edge portion sandwiched between a first block 12a and a second block 12b is provided on the upper side of the body portion 14, and the diaphragm 50 is provided on the upper side of the diaphragm 50. A pilot chamber 52 is formed by the recess 56 of the first block 12a. The diaphragm 50 is provided with a pair of disc members 54a and 54b for sandwiching the diaphragm 50 between the upper surface side and the lower surface side, and the other end portion of the stem 48 is provided at the center of the upper disk member 54a. It is fixed.

The diaphragm 50 is, for example,
The upper diaphragm 50a formed of a rubber material such as NBR and the lower diaphragm 50b formed of a resin material such as polytetrafluoroethylene (PTFE) are integrally configured.

Therefore, the diaphragm 50, the set of disk members 54a and 54b, and the stem 48 are provided so as to be integrally displaced in the vertical direction under the action of the pressure fluid supplied to the pilot chamber 52. There is.

Inside the cover member 16, an air supply solenoid valve 56 and an exhaust solenoid valve 58, which are normally closed type two-way valves, are arranged at a predetermined distance. The pressurized fluid is supplied to the air supply solenoid valve 56 via a first passage 62 communicating with the pilot port 60. Further, the second passage 6 is provided between the air supply solenoid valve 56 and the exhaust solenoid valve 58.
4 is provided and is connected to the pilot chamber 52 by a third passage 66 branched from the second passage 64.
Further, an exhaust passage 68 communicating with the atmosphere is connected to the exhaust solenoid valve 58, and is provided so as to be able to exhaust to the outside via the exhaust passage 68.

In this case, the air supply solenoid valve 56 functions as a pilot pressure air supply valve which controls the pilot pressure supplied to the pilot chamber 52, and the exhaust air solenoid valve 58.
Is a pilot pressure exhaust valve that exhausts the pressure fluid supplied to the air supply solenoid valve 56 to the outside,
A current signal (pulse signal) is derived from the control circuit 70 with respect to an electromagnetic coil (not shown), so that on / off control is appropriately performed. The control circuit 70 is connected to a pressure display section 72 that digitally displays the set pressure, the secondary pressure, and the like.

Further, a pressure sensor 76 for detecting the pressure of the pressure fluid supplied to the fluid pressure device side (not shown) through the feedback passage 74 communicating with the pressure adjusting port 20 is provided inside the cover member 16. , The pressure sensor 7
The detection signal 6 is led to a control circuit 70 including an electric circuit board, a connector and the like (not shown). In the control circuit 70, the preset fluid pressure is compared with the fluid pressure corresponding to the detection signal, and feedback control is performed so that the deviation becomes zero.

In this case, the third passage 66 is opened by energizing / deactivating the air supply solenoid valve 56 and the exhaust solenoid valve 58 by a control signal output from the control circuit 70 via a connector (not shown). Through pilot room 52
The pilot pressure supplied to is controlled.

Pipes (not shown) such as tubes screwed into screw holes (not shown) are connected to the exhaust port of the exhaust solenoid valve 58 and the exhaust port 44, respectively, and the pressure fluid is supplied to the outside through the pipes. (For example, outside the clean room)
It is better to exhaust to. At this time, it is preferable that the exhaust electromagnetic valve 58 and the exhaust port 44 are electrically connected to perform concentrated exhaust.

The fluid pressure adjusting apparatus 10 according to the embodiment of the present invention is basically constructed as described above. Next, its operation and action and effect will be explained.

The fluid pressure adjusting device 10 is in a state in which the power is turned on, and as shown in FIG.
The air supply valve 30 covered by the covering member 40 has the seat portion 3
The state in which the valve 8 is seated and the valve is closed is defined as the initial position.

In the initial position, the pressure fluid is supplied to the pilot port 60 under the urging action of the pressure fluid supply source (not shown). The pressure fluid supplied to the pilot port 60 is introduced into the air supply solenoid valve 56 and the exhaust solenoid valve 58 through the first passage 62, and a control signal (ON / OFF signal) output from the control circuit 70 is output. By controlling the air supply solenoid valve 56 and / or the exhaust solenoid valve 58 by turning on / off respectively, the pilot pressure is controlled to a predetermined pressure.

The pilot pressure controlled by the solenoid valve 56 for air supply and / or the solenoid valve 58 for exhaust air is controlled by the third pressure.
It is supplied to the pilot chamber 52 provided on the upper side of the diaphragm 50 via the passage 66. Under the action of the pilot pressure, the diaphragm 50 and the pair of disc members 54
The a, 54b and the stem 48 are integrally lowered. As the stem 48 descends, the air supply valve 30 moves to the valve spring 3
6 is displaced downward against the spring force of 6 and the air supply valve 30 covered by the covering member 40 is separated from the seat portion 38, whereby the valve is opened (see FIG. 2).

Therefore, the pressure fluid supplied to the supply port 18 and the seat member 3 and the covering member 40 for covering the air supply valve 30.
After being depressurized to a predetermined pressure fluid through the clearance with 8, the pressure on the secondary side regulated to a set pressure value from a fluid pressure device (not shown) that functions as a secondary side load from the pressure regulating port 20. Fluid is supplied.

The pilot pressure supplied to the pilot chamber 52 is supplied to the feedback passage 7 communicating with the pressure adjusting port 20.
4 is introduced into the pressure sensor 76, and the control circuit 70 performs feedback control based on the detection signal output from the pressure sensor 76.

As described above, by displacing the stem 48 in the vertical direction integrally with the diaphragm 50 by the pressure of the pressure fluid supplied to the pilot chamber 52,
A decompression effect is achieved by the opening / closing action of the air supply valve 30.

That is, under the action of the pilot pressure introduced into the pilot chamber 52, the diaphragm 50 and the pair of disk members 54a, 54b are given a downward pressing force integrally, and this diaphragm 50 is applied. And the force of pressing the pair of disc members 54a, 54b downward and the spring force of the valve spring 36 balance, so that the air supply valve 30 covered by the covering member 40 is seated on the seat portion 38. As a result, the valve is closed, and a preset desired fluid pressure is supplied to the fluid pressure device side via the pressure adjusting port 20.

In the present embodiment, the covering member 40 for shielding the air supply valve 30 and the valve spring 36 is provided in the communication passage 22,
Dust such as metal powder and abrasion powder generated at the sliding portion of the valve spring 36 that expands and contracts with the displacement of the air supply valve 30 is covered with the covering member 4 described above.
Is captured by 0. Therefore, the dust is not
It is possible to prevent the pressure fluid from being contaminated because the covering member prevents the pressure fluid flowing through the mixture 2 from flowing out together. As a result, the body part 14
By preventing the dust and the like generated inside the chamber from being discharged to the outside, it can be suitably used in an environment such as a clean room where cleanliness is required.

[0039]

According to the fluid pressure adjusting device of the present invention, the following effects can be obtained.

That is, the valve body and the spring member are shielded by the sealing means, and the valve body and the spring member are sealed from the pressure fluid flowing through the fluid passage. Even if such dust is generated, it is prevented that the dust is mixed with the pressure fluid flowing through the fluid passage. Therefore, it can be preferably used in an environment such as a clean room where cleanliness is required.

[Brief description of drawings]

FIG. 1 is a schematic longitudinal sectional view of a fluid pressure adjusting device according to an embodiment of the present invention, taken along the axial direction.

FIG. 2 is a partially omitted enlarged vertical sectional view when the air supply valve shown in FIG. 1 is displaced and is in a valve open state.

FIG. 3 is a schematic configuration circuit diagram of a pressure control valve according to a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Fluid pressure adjusting device 14 ... Body part 16 ... Cover member 18 ... Supply port 20 ... Pressure adjusting port 22 ... Communication passage 24 ... Recess 30 ... Air supply valve 34 ... Annular recess 36 ... Valve spring 38 ... Seat 40 ... Cover Member 48 ... Stem 50 ... Diaphragm 52 ... Pilot chamber 54a, 54b ... Disk member 56 ... Air supply solenoid valve 58 ... Exhaust solenoid valve 70 ... Control circuit 74 ... Feedback passage 76 ... Pressure sensor

Claims (3)

[Claims] 1. A fluid pressure adjusting device for supplying a predetermined fluid pressure adjusted to a reduced pressure to a fluid pressure device operated by a fluid pressure, wherein a supply port into which a pressure fluid is introduced and a pressure adjusted to a reduced pressure. A housing provided with a pressure adjusting port for leading out a fluid and a fluid passage for connecting the supply port and the pressure adjusting port, respectively, and an axial direction inside the housing under the action of the supplied pilot pressure. And a spring member that presses the valve body toward the seating portion, the valve body being displaceably provided and being seated on the seating portion to cut off the communication between the supply port and the pressure adjusting port. A fluid pressure adjusting device, comprising: a sealing means for shielding the body and the spring member from the pressure fluid flowing through the fluid passage. 2. The fluid pressure adjusting device according to claim 1, wherein the sealing means includes a covering member that shields a concave portion of a housing in which the valve body and the spring member are disposed, and the covering member serves to prevent the valve body and the valve body. A fluid pressure adjusting device, characterized in that a pressure fluid is prevented from entering a spring member. 3. The fluid pressure adjusting device according to claim 1, wherein the covering member is formed of a flexible member, and a part of the valve body is covered so that the valve body is displaced. A fluid pressure adjusting device, which is provided flexibly.