JP2003083468A - Method and structure for purging gas in valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect an actuator part and components and a line of a drive source by purging gas permeating or leaking from a body side to the actuator part side. SOLUTION: In this method for purging gas permeating or leaking to the actuator part in a valve 10, the valve comprises the body 11, a valve mechanism body 20 operated inside the body 11 for controlling fluid to be controlled, the actuator part for operating the valve mechanism body, and a line inserting part 80 for passing through a line L connecting the actuator part and the drive source 65. Gas circulating parts 90, 91 for communicating inside and outside of the actuator part are provided, and gas for purging Ap is fed from the line inserting part 80 inside the actuator part and discharged from the gas circulating parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas purging method and structure in a valve used for controlling a fluid.

[0002]

2. Description of the Related Art For example, a reduced pressure used for controlling various fluids such as corrosive fluids, organic solvents, ozone water, electrolyzed water, and gas to a predetermined state (including adjustment or switching; the same applies hereinafter). The valve, the back pressure valve, the safety valve, the opening control valve, the mixing ratio control valve, the on-off valve, and the like include a body having a chamber through which the controlled fluid flows, and a body inside the body for controlling the controlled fluid. There is a valve mechanism body that operates in accordance with (1) and an actuator section that operates the valve mechanism body. An electromagnetic actuator that uses electromagnetic force may be used as an actuator section that operates the valve mechanism, and in that case, a wire insertion section that allows wiring such as a lead wire or a harness that connects the actuator section and the drive source is provided. To be The valve mechanism may be operated by using an air-operated method that uses pressure-regulated gas (mainly pressurized gas), but in that case, the responsiveness is caused by the compressibility of the pressure-regulated gas. There is a disadvantage that it is bad.

In a valve having an actuator such as the electromagnetic actuator, the controlled fluid (in the case of gas) flowing in the chamber of the body body or the gas in the controlled fluid permeates or leaks to the actuator side. May occur. In that case, there is a possibility that the gas may cause inconveniences such as corrosion of actuator parts, drive source components (mainly electrical parts), wiring, and the like.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is configured to purge (remove) gas that permeates or leaks from the body side to the actuator side to configure the actuator and drive sources. Provided is a gas purging method and structure in a valve capable of protecting parts, wiring and the like.

[0005]

That is, the invention of claim 1 is a body having a chamber through which a fluid to be controlled flows, and a valve mechanism that operates in the body to control the fluid to be controlled. A gas that permeates or leaks from the body side to the actuator side in a valve that includes an actuator section that operates the valve mechanism body and a wire insertion section that passes a wire that connects the actuator section and a drive source. A method of purging the actuator part, wherein a gas circulation part that communicates the inside and outside of the actuator part is provided, a purging gas is sent from the wiring insertion part into the actuator part, and the purging gas is discharged from the gas circulation part. The present invention relates to a gas purging method for a valve.

According to a second aspect of the present invention, a body body having a chamber through which a controlled fluid flows, a valve mechanism operating in the body body for controlling the controlled fluid, and the valve mechanism body are operated. An actuator part, and a wire insertion part through which a wire connecting the actuator part and the drive source is inserted,
A gas flow portion provided so as to communicate the inside and outside of the actuator portion, and a gas supply portion for supplying a purge gas for purging gas that permeates or leaks from the body main body side to the actuator portion side. In the valve, a purge gas from the gas supply unit is sent from the wiring insertion unit into the actuator unit, and the purge gas is discharged from the gas flow unit, to a gas purge structure in the valve. Pertain.

According to a third aspect of the present invention, in the second aspect, the valve mechanism has a diaphragm portion, and gas that permeates or leaks from the body body side to the actuator side through the membrane portion of the diaphragm portion. The present invention relates to a gas purging structure in a valve for purging gas with a purging gas.

A fourth aspect of the present invention relates to the gas purging structure in the valve according to the second or third aspect, wherein the actuator portion is an electromagnetic actuator.

A fifth aspect of the present invention relates to the gas purging structure in the valve according to the fourth aspect, wherein the valve is an opening / closing valve, and an electric resistor is provided in a wiring connecting the actuator portion and the drive source.

A sixth aspect of the present invention relates to the gas purging structure in the valve according to any one of the second to fifth aspects, wherein the valve is provided with a plurality of gas circulation portions communicating the inside and outside of the actuator portion.

The invention of claim 7 relates to the gas purging structure in the valve according to any one of claims 2 to 6, wherein the valve is an opening / closing valve having a suck back mechanism.

[0012]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail below with reference to the accompanying drawings. 1 is a sectional view showing a valve according to an embodiment of the present invention, FIG. 2 is a sectional view showing a valve according to another embodiment, FIG. 3 is a sectional view showing a valve according to still another embodiment, and FIG. FIG. 8 is a sectional view showing a valve according to still another embodiment.

The valve 10 shown in FIG. 1 relates to an embodiment of the present invention, and is a pressure control valve for controlling the pressure of the secondary fluid to a predetermined state in response to the pressure fluctuation of the primary fluid. It is used as a control valve (pressure reducing valve). The valve 10 includes a body 11, a valve mechanism body 20, an actuator portion 60, a wire insertion portion 80, and a gas circulation portion 9
0 and 91 and a gas supply unit 95 are provided. The controlled fluid controlled by the valve 10 includes various fluids such as pure water, corrosive fluid, organic solvent, ozone water, electrolyzed water, gas and the like.

The body main body 11 is made of a resin having high corrosion resistance and chemical resistance such as a fluororesin in this embodiment, and has a first chamber 12 having an inflow portion 13 for the controlled fluid.
A second chamber 14 having an outflow 15 for the controlled fluid, the first chamber 12 and the second chamber 14
Has a communication flow path 17 that communicates with the valve seat 18 and is formed with a valve seat 18. In the communication flow path 17, the opening amount between the valve portion 22 and the valve seat 18 of the valve mechanism 20 is changed by the operation of the valve mechanism 20 described later, and the primary side (the inflow portion 13
Flow rate (secondary side pressure) of the controlled fluid flowing from the side) to the secondary side (outlet 15 side). The body main body 11 of this embodiment includes a first block 11a and a second block 11b.
And a cover case 61 of the actuator section 60, which will be described later, are integrally assembled by an appropriate fixing member such as a bolt. In addition, the inflow section 1
An inflow pipe is connected to 3, and an outflow pipe is connected to the outflow portion 15.

Like the body 11, the valve mechanism 20 is made of a resin having a high corrosion resistance and a high chemical resistance such as a fluororesin in this embodiment. As defined in the invention of claim 3, the valve mechanism 20 of the embodiment has a rod portion 21 that is inserted into the communication passage 17 so as to be able to move forward and backward, and inside the first chamber 12 (on the inflow portion 13 side). And a second diaphragm portion 40 disposed inside the second chamber 14 (outflow portion 15 side).

The rod portion 21 has a valve portion 22 that opens and closes the valve seat 18. In the present embodiment, the valve portion 22
Is located on the first chamber 12 side so that the rod portion 21
It is formed so as to project to the outer peripheral surface. Further, in this embodiment, the surface of the valve portion 22 is formed as a tapered surface. In addition, the first diaphragm portion 30 is the rod portion 2
1 has a thin film portion (movable portion) 31 which is a diaphragm surface and is provided at an end portion on the first chamber side, and an outer peripheral seal portion 32 on the outer peripheral side thereof. Further, the second diaphragm portion 40 is provided at the end portion of the rod portion 21 on the second chamber side, and is a thin film portion (movable portion) 41 that is a diaphragm surface.
And an outer peripheral seal portion 42 on the outer peripheral side thereof. In this embodiment, the outer diameter (diaphragm effective diameter) of the film portion 31 of the first diaphragm portion 30 is equal to the second diaphragm portion 40.
Is smaller than the outer diameter (effective diameter of the diaphragm) of the film portion 41.

The first diaphragm portion 30 and the second diaphragm portion 40 have outer peripheral seal portions 32 and 42, respectively.
Is fixed to the body 11 and the first chamber 12
It is arranged inside or inside the second chamber 14, respectively. In the embodiment, as shown, the first diaphragm portion 30 is
The outer peripheral seal portion 32 is sandwiched and fixed between the first block 11a and the second block 11b of the body body 11. On the other hand, in the second diaphragm portion 40, the outer peripheral seal portion 42 has the outer peripheral seal portion 42 of the body main body 11.
It is sandwiched and fixed between b and the cover case 61 of the actuator unit 60.

Due to the first diaphragm portion 30, the first chamber 12 is located upstream of the valve seat 18 inside the first diaphragm portion 30, the first valve chamber 51 including the inflow portion 13, and the first diaphragm portion. 30 First pressure regulation chamber 52 outside
It is divided into and. The second diaphragm portion 40 causes the second chamber 14 to be located downstream of the valve seat 18 inside the second diaphragm portion 40, to include the second valve chamber 55 including the outflow portion 15, and the second diaphragm portion 40. It is divided into an outer second pressure adjusting chamber 56.

Here, the controlled fluid (in the case of gas) or the gas in the controlled fluid flowing in the second valve chamber 55 through the film portion 41 of the second diaphragm portion 40 is the actuator portion 60. There is a risk of leakage or permeation to the side (second pressure regulation chamber 56 side).

Further, in this embodiment, the rod portion 21 of the valve mechanism 20 is integrally provided with the second diaphragm portion 40, and the rod portion 21 has the first diaphragm portion 30.
Is fixed by screwing. In contrast to this example, the rod portion 21 may be integrally provided with the first diaphragm portion 30, and the second diaphragm portion 40 may be screwed and fixed to the rod portion 21, or each portion may be screwed. It may be fixed and fixed, or each part may be integrally formed. Further, as in the valve described in Japanese Patent Laid-Open No. 2000-193106, the rod portion 21 may be composed of two members which can be separated from each other and can be loosely fitted and coupled.

Further, in the present embodiment, the connecting shaft portion 45 connected to the actuating member 64 of the actuator portion 60, which will be described later, is provided upright on the outer side (upper side in the drawing) of the second diaphragm portion 40.

The actuator section 60 for operating (moving up and down in the figure) the valve mechanism 20 is the body body 1
It is provided on the outer side (upper side) of the first second block 11b.
The actuator section 60 in this embodiment is composed of an electromagnetic actuator that utilizes electromagnetic force, as defined in the invention of claim 4. Reference numeral 61 in the figure denotes a cover case assembled on the upper side of the second block 11b of the body body 11, 62 denotes a metal cover, 63 denotes a coil,
Reference numeral 64 denotes an operating member that advances and retreats by an electromagnetic force generated by passing a current through the coil 63 and is coupled (screwed) to the coupling shaft portion 45 of the valve mechanism 20, and 65 denotes a drive source (drive output power source), Is a wire such as a conducting wire (electric wire, cord or the like) or a harness connecting the coil 63 and the drive source 65, 61o is an insertion hole formed in the cover case 61 for inserting the wire L, and 61r is inside the cover case 61. Second pressure regulation chamber 56
A communication hole for communicating with a purging gas described later, 6
Reference numeral 2o is an insertion hole formed in the metal cover 62 for inserting the wiring L. The actuator 60 may be a moving coil, normally closed (NC), or normally open (NO). Also, a coil (solenoid) and a magnetic body (magnet) may be used together. Furthermore, the actuator unit 60 is not limited to the electromagnetic actuator.

The second diaphragm 40 is regulated by the actuator 60 in a predetermined direction at a predetermined pressure (mainly inward (downward in the figure)). Further, in this embodiment, in the first pressure adjusting chamber 52 outside the first diaphragm portion 30, a forward and backward pressing member 71 that presses the first diaphragm portion 30 from the outside (lower side), An urging member 72 such as a spring having a predetermined spring constant for urging the pressing member 71 toward the first diaphragm portion (upward in the drawing) is provided, and the pressing member 71 and the urging member 72 cause the first diaphragm portion to move. 30 is regulated, and here, a constant regulated pressure is always applied to the first diaphragm portion 30. In the illustrated example, the pressing member 71 is attached to the first diaphragm portion 30, and the biasing member 72 is mounted between the inner wall of the first pressure adjusting chamber 52 and the pressing member 61. The configuration for adjusting the pressure of the first diaphragm portion 30 is not limited to the above example, and a pressurized gas or a solenoid (electromagnet) may be employed. Reference numeral 73 in the drawing represents a breathing path through which air in and out of the first pressure adjusting chamber 52 flows.

The wiring insertion portion 80 is for passing the wiring L connecting the coil 63 of the actuator portion 60 and the drive source 65, and the wiring insertion portion 80 of this embodiment is
Protective tube 81 through which wiring L is inserted and joint body 83
And a cap nut 84, and the enlarged diameter end portion 82 of the protection tube 81 is attached to the joint body 83 and is tightened with the cap nut 84 to be attached to the cover case 61 of the actuator portion 60. Of course, the structure for attaching the wire insertion portion 80 is not limited to the joint structure.

The gas flow sections 90 and 91 are for supplying purge gas (air) to the inside of the actuator section 60 (including the second pressure adjusting chamber 56 outside the second diaphragm section 40. The same applies hereinafter). Alternatively, it is for discharging the purging gas supplied into the actuator unit 60,
The cover case 61 of the actuator unit 60 or the body body 1 so that the inside and outside of the actuator unit 60 communicate with each other.
1 is provided. The positions where the gas flow units 90 and 91 are arranged are not limited to the above example.

In the present embodiment, as defined in the sixth aspect of the invention, two gas flow sections 90 and 91 are provided. Specifically, in the vicinity of the body 11 of the cover case 61 of the actuator section 60, the first gas flow section 90 that communicates the inside of the second pressure regulation chamber 56 with the outside of the valve.
And an outer end of the cover case 61 (an end where the wiring insertion portion 80 is disposed, an upper end in the drawing).
Is provided with a second gas circulation portion 91 that communicates the inside of the cover case 61 with the outside of the valve.

The gas supply unit 95 is for supplying a purge gas (air, N ₂ gas or the like) for purging the gas that permeates or leaks from the body main body 11 side to the actuator unit 60 side, and is a compressor or the like. Composed. In addition,
The gas supply unit 95 may be provided integrally with the valve (body body 11 or actuator unit 60) or may be provided separately.

In the valve 10 having the above structure, the actuator 60, the pressing member 71, and the biasing member 72 cause the valve mechanism 20 to pass through the first diaphragm portion 30 and the second diaphragm portion 40 of the valve mechanism 20. Inward pressure regulation pressure is constantly applied. In a normal control state (water flow state), the inward pressure-adjusting pressure is configured to maintain balance when the controlled fluid has a predetermined pressure (predetermined flow rate), and the valve of the valve mechanism body 20 is controlled. Portion 22 and valve seat 18
The opening amount between and is kept constant. As a result, the controlled fluid that has flowed into the second valve chamber 55 from the inflow portion 13 side (primary side) through the first valve chamber 51 is discharged to the outflow portion 15 side (secondary side) by a predetermined flow rate.

When there is any change in the controlled fluid on the inflow section 13 side (primary side), the change appears as a pressure fluctuation on the primary side, and the second of the valve mechanism body 20 to which the second set pressure is applied. It appears as back pressure (outward pressure) fluctuation with respect to the diaphragm portion 40. This outward-side fluctuating pressure on the primary side, the actuator section 60 and the pressing member 71,
The valve mechanism 20 fluctuates in an attempt to maintain balance with the inward pressure regulation pressure by the urging member 72, and the valve portion 22 moves accordingly, so that the opening amount between the valve portion 22 and the valve seat 18 is reduced. By changing, the pressure (flow rate) of the controlled fluid is controlled.

On the other hand, when the pressure on the secondary side becomes high, the back pressure, that is, each diaphragm portion 3 of the valve mechanism 20.
The outward pressure acting on 0, 40 is higher than in the normal control state. As a result, the second diaphragm portion 40 moves outward, the valve portion 22 and the first diaphragm portion 30 move to the second diaphragm portion 40 side accordingly, and the valve portion 22 abuts the valve seat 18 to communicate. The flow path 17 is closed.

Next, an example of a gas purging method in the valve 10 having the above structure will be described. In this example, the purging gas Ap from the gas supply part 95 is transferred to the inside of the actuator part 60 (the second diaphragm part) through the tip end port 81 a of the protection tube 81 of the wiring insertion part 80 and the first gas circulation part 90. 40 including the second pressure adjusting chamber 56 outside.)
To the actuator 60.
By circulating the gas inside and discharging the circulated purge gas Ap from the second gas circulation portion 91, the gas leaking or permeating from the body body 11 side to the actuator portion 60 side is purged.

By performing the gas purging in this way, the purging gas Ap can be efficiently circulated in the actuator section 60, particularly in the metal cover 62 (near the coil 63), and the inside of the actuator section 60 can be efficiently circulated. It is possible to reliably purge the gas that has leaked or permeated into the device, and protect the components of the actuator unit 60, the components of the drive source 65 (mainly electrical components), wiring, and the like. As a result, it is suitable for controlling a fluid having properties such as strong acid, strong alkali, and high concentration ozone.

A second gas flow section 91 for discharging the purging gas Ap and an unnecessary fluid discharge channel (a discharge channel isolated from the atmosphere in the workplace) installed in the workplace (factory or the like) are provided. By connecting via a pipe, it is possible to prevent the gas leaked or permeated to the actuator 60 side from affecting the atmosphere in the workplace.

Here, in the above embodiment, two gas circulation portions 90 and 91 are provided for communicating the inside and outside of the actuator portion 60, but the number is not limited to this, and three or more may be provided, or As shown in FIG.
You may make it provide only one. In the valve 10A shown in FIG. 2, the purging gas A from the gas supply unit 95 is used.
p is the tip opening 8 of the protective tube 81 of the wiring insertion portion 80.
The purge gas Ap is sent to the inside of the actuator section 60 via 1a, the purge gas Ap is circulated in the actuator section 60, and the circulated purge gas Ap is discharged from the gas circulation section 90, so that the body main body 11 side Gas leaking or permeating to the actuator 60 side is purged. This has the advantages that the gas purging effect can be obtained, the structure is simple (compact), and the cost can be reduced.

The present invention is not limited to the above-mentioned two embodiments, and can be implemented by appropriately modifying a part of the configuration without departing from the spirit of the invention. For example, in each of the above-mentioned embodiments, the valve mechanism having the two diaphragm portions is provided, but the invention is not limited to this.
The present invention can also be applied to a valve in which one or three or more diaphragm parts are provided in the valve mechanism. Further, the present invention can be applied to a valve having no diaphragm portion.

Further, although the valve of the above embodiment is a pressure control valve used for controlling the fluid on the secondary side to a predetermined pressure state, the present invention is not limited to this pressure control valve, and the present invention is not limited to this. Widely applicable to various valves such as pressure control valve (also called back pressure valve or safety valve) that controls the primary side fluid to a predetermined pressure state, on-off valve, opening control valve, mixing ratio control valve, etc. You can

The on-off valve 10B shown in FIG. 3 is an on-off valve (valve) to which the present invention is applied and has a suck back mechanism as defined in the invention of claim 7. The on-off valve 10B includes a body 100 and a valve mechanism 110.
Except for the above, the valves 10 and 10A have substantially the same configuration as the valves 10 and 10A of the above-described embodiment, and therefore, the same parts as those of the valves 10 and 10A are designated by the same reference numerals and the description thereof will be omitted. Reference numeral 101 relating to the body main body 100 in the drawing is a first chamber (inflow side chamber), 102 is an inflow part for the controlled fluid, 103 is a second chamber (outflow side chamber), 104
Is an outlet for the controlled fluid, 105 is a communication channel communicating with the first chamber 101 and the second chamber 103,
Reference numeral 106 is a valve seat, and 107 is a breathing path for letting air in and out of the second chamber 103 (strictly speaking, the outer space of the second diaphragm portion).

Reference numeral 1 for the valve mechanism 110 in the figure
Reference numeral 11 is a rod portion that is inserted into the communication channel 105 so as to be able to move forward and backward, 120 is a first diaphragm portion arranged in the first chamber 101, and 121 is a first diaphragm portion 12.
0 is a membrane portion, 122 is an outer peripheral sealing portion, 123 is an opening / closing portion that similarly opens and closes the communication passage 105 by contacting with and separating from the valve seat 106, and 124 is the first diaphragm portion 12
0 is erected outside (upper side in the figure) of actuator unit 6
0 is a connecting shaft portion connected to the operating member 64, 130 is a second diaphragm portion arranged in the second chamber 103,
Reference numeral 131 is a film portion of the second diaphragm portion 130, and 132 is a peripheral seal portion.

In this on-off valve 10B, when the valve mechanism 110 is actuated by the action of the actuator section 60 to close the communication passage 105 and stop the outflow of the controlled fluid from the outflow section 104, the second side on the outflow side is used. The volume of the space inside the second diaphragm part 130 in the chamber 103 increases, the pressure in the space decreases, and the liquid in the outflow pipe connected to the outflow part 104 is drawn back into the on-off valve 10B, so-called liquid drop. Can be prevented (suck back mechanism). It should be noted that purging of gas that permeates or leaks to the actuator unit 60 side through the first diaphragm unit 120 in the opening / closing valve 10B is performed in the same manner as in the above-described embodiment.

The on-off valve 10C shown in FIG. 4 is also an on-off valve (valve) having a suck back mechanism to which the present invention is applied, like the on-off valve 10B shown in FIG. The on-off valve 10C is the same as the valve 10, 1 of the above embodiment except for the body 200, the valve mechanism 210, and the actuator 230.
Since it has substantially the same structure as 0A, 10B, the same parts as those of the valves 10, 10A, 10B are designated by the same reference numerals, and the description thereof will be omitted. Reference numeral 201 related to the body main body 200 in the drawing is a first chamber (inflow side chamber),
202 is an inflow part for the controlled fluid, 203 is a second chamber (outflow side chamber), 204 is an outflow part for the controlled fluid, and 205 is a communication connecting the first chamber 201 and the second chamber 203. A flow passage and 206 are valve seats.

Reference numeral 2 for the valve mechanism 210 in the figure
Reference numeral 11 denotes a rod portion that is inserted into the communication passage 205 so as to be able to move back and forth, and 212 is mounted on an outer peripheral surface of the rod portion 211 on the tip end side, and comes in contact with and separates from the valve seat 206 to form the communication passage 2
The valve seal member 213 for opening and closing 05 is a rod portion 21.
1 is a piston portion (large diameter portion) provided on the actuator portion side (upper side in the drawing) of FIG. Further, reference numeral 231 relating to the actuator portion 230 in the figure indicates the body body 200.
Of the cover case, 232 is a metal cover, 233 is a coil, and 234 is an operating member that moves forward and backward by an electromagnetic force generated by passing an electric current through the coil 233 and is coupled (screwed) to the valve mechanism 210. , 23
Reference numeral 5 denotes a cylinder portion for accommodating the piston portion 213 of the valve mechanism 210 so that the piston portion 213 can move forward and backward, and 236 is formed so as to connect the cylinder portion 235 and the first chamber 201 of the body body 200. An insertion portion slidably inserted, a seal member 237 interposed between the wall surface of the insertion portion 236 and the outer surface of the rod portion 211, and a gas flow portion 238 communicating the inside and outside of the cylinder portion 235 (here, a purge gas is used). A gas discharge part for discharging to the outside of the valve) 239 is the cylinder part 235 and the cover case 2.
It is a communication hole that communicates with the inner upper part of 31 (the space where the metal cover 232 and the like are arranged).

In this on-off valve 10C, when the valve mechanism 210 is actuated by the action of the actuator section 230 to close the communication passage 205 and stop the outflow of the controlled fluid from the outflow section 204, the second side on the outflow side. The volume of the space excluding the rod portion 211 of the valve mechanism 210 of the chamber 203 (the volume capable of containing the controlled fluid) increases, and the second chamber 20
The pressure inside 3 decreases, and the liquid in the outflow pipe connected to the outflow portion 204 can be returned to the inside of the on-off valve 10C, so-called dripping can be prevented (suck back mechanism).

Further, in the on-off valve 10C of this example,
As defined in the invention of claim 5, an electric resistor R is provided in the middle of the wiring L connecting the actuator unit 230 and the drive source 65. As a result, the valve mechanism 2
The responsiveness during the operation of 10 is improved, in other words,
The time-and-pressure method improves the accuracy of the valve opening time. In addition, purging of gas that permeates or leaks into the actuator portion 230 through the space between the wall surface of the insertion portion 236 and the outer surface of the rod portion 211 in the on-off valve 10C is performed in the same manner as in the above embodiment.

[0044]

As shown and described above, according to the gas purging method and structure of the valve of the present invention, the gas leaked or permeated into the actuator section can be purged by the purging gas, and the constituent parts of the actuator section. It is possible to protect the components and wiring of the drive source. As a result, the valve can be suitably used for controlling a fluid having properties such as strong acid, strong alkali, and high concentration ozone.

According to the third aspect of the present invention, the valve mechanism body has a diaphragm portion, and gas that permeates or leaks from the body body side to the actuator side through the membrane portion of the diaphragm portion. If the purge gas is used for purging, it is possible to solve the problem of permeated or leaked gas in a valve using a diaphragm portion that is widely used at present.

Further, when the actuator section is constituted by the electromagnetic actuator as in the invention of claim 4, the responsiveness at the time of actuation of the valve mechanism becomes excellent. In particular, when the valve is an on-off valve and an electric resistor is provided in the wiring connecting the actuator unit and the drive source, the response at the time of actuation of the valve mechanism is further improved. Improved, valve open time (outflow rate)
The accuracy of is good.

If a plurality of gas circulation portions communicating between the inside and outside of the actuator portion are provided as in the sixth aspect of the present invention, at least one of the plurality of gas circulation portions together with the wiring insertion portion serves as a purge gas. It can be used for supply and the remaining gas flow section can be used for discharge of the purging gas, thereby improving the accuracy of purging gas leaked or permeated into the actuator section.

Further, when the valve is an on-off valve having a suckback mechanism as in the invention of claim 7, the outflow pipe connected to the outflow portion when the outflow of the controlled fluid from the outflow portion is stopped. The fluid inside can be drawn back into the on-off valve, so-called dripping can be prevented, and the accuracy of fluid control is improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a valve according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a valve according to another embodiment.

FIG. 3 is a sectional view showing a valve according to still another embodiment.

FIG. 4 is a cross-sectional view showing a valve according to still another embodiment.

[Explanation of symbols]

10 valves 11 body 12 First chamber 13 Inflow section 14 Second chamber 15 Outflow section 20 valve mechanism 30 First diaphragm part 40 Second diaphragm part 60 Actuator part 65 Drive source 80 wiring insertion part 90, 91 Gas flow section 95 gas supply unit Ap Purge gas L wiring

Claims (7)

[Claims] 1. A body body having a chamber through which a controlled fluid flows, a valve mechanism body operating in the body body for controlling the controlled fluid body, an actuator section for operating the valve mechanism body, and A method of purging gas that permeates or leaks from the body main body side to the actuator section side in a valve provided with a wiring insertion section for passing a wiring connecting an actuator section and a drive source, A gas purging method for a valve, comprising: providing a communicating gas flow section, sending a purging gas into the actuator section from the wiring insertion section, and discharging the purging gas from the gas flow section. 2. A body body having a chamber in which a controlled fluid flows, a valve mechanism body operating in the body body for controlling the controlled fluid body, an actuator section for operating the valve mechanism body, A wire insertion part for passing a wire connecting the actuator part and the drive source, a gas circulation part provided so as to communicate the inside and outside of the actuator part, and a gas that permeates or leaks from the body side to the actuator part side is purged. In a valve provided with a gas supply unit for supplying a purge gas for performing, the purge gas from the gas supply unit is sent from the wiring insertion unit into the actuator unit, and the purge gas is supplied from the gas flow unit. A gas purging structure for a valve, which is configured to discharge. 3. A valve mechanism body having a diaphragm portion, and a gas for permeating or leaking from the body main body side to the actuator portion side through the membrane portion of the diaphragm portion is purged by a purging gas. A gas purging structure in the valve described in 1. 4. The gas purging structure for a valve according to claim 2, wherein the actuator portion is composed of an electromagnetic actuator. 5. The gas purging structure for a valve according to claim 4, wherein the valve is an on-off valve, and an electric resistor is provided in a wiring connecting the actuator unit and the drive source. 6. The gas purging structure for a valve according to claim 2, wherein a plurality of gas circulation portions that communicate the inside and outside of the actuator portion are provided. 7. The gas purging structure for a valve according to claim 2, wherein the valve is an opening / closing valve having a suck back mechanism.