JP2009024749A - Diaphragm type fluid equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inhibit pollution of a fluid passage and the like and suitably inhibit dielectric breakdown of a diaphragm caused by electrostatic charging. <P>SOLUTION: In a liquid control valve 10, a diaphragm valve element 26 made of synthetic resin (insulating material) such as fluororesin is connected to a lower end portion of a piston rod 16. The diaphragm valve element 26 has a boss portion 26a connected to the piston rod 16, a peripheral portion 26b caught by a cylinder body 12 and a flow passage body 14, and a diaphragm membrane portion 26c formed between the boss portion 26a and the peripheral portion 26b. A conductive layer 41 is formed on a side of the diaphragm valve element 26 not contacting with liquid over its entire surface. The conductive layer 41 is composed by laminating a high resistance layer of a relatively high resistance and a low resistance layer of a resistance lower than the high resistance layer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technology that can suitably prevent dielectric breakdown of a diaphragm in a diaphragm type fluid device that allows fluid to enter and exit through the operation of the diaphragm.

  In this type of diaphragm type fluid device, there is a concern that when the diaphragm film surface is charged, the dielectric breakdown of the diaphragm is caused by the charging. As a countermeasure, a fluid device has been proposed in which a conductive member having corrosion resistance is provided in the vicinity of the membrane portion of the diaphragm so as to penetrate the fluid passage, and a grounding means for grounding the conductive member is provided in the body body. (For example, refer to Patent Document 1).

In the above fluid equipment, since the diaphragm can be operated normally without interfering with the bending operation of the diaphragm membrane portion, the diaphragm membrane portion is prevented from being broken down with a simple configuration without impairing the diaphragm characteristics. I was able to do it.
JP 2007-78019 A

  However, in the above fluid device, since the conductive member is exposed in the fluid passage, the conductive member may be eluted when used for a long period of time, resulting in contamination of the fluid passage. In this case, even if a material having corrosion resistance is used as the conductive member, there may be a disadvantage that the applicable material is limited depending on the fluid to be used each time. Further, in the above fluid device, since the conductive member is provided at the peripheral portion of the diaphragm so as to maintain the bending operation of the membrane portion of the diaphragm, it is difficult to eliminate the charge on the membrane portion near the center of the diaphragm. Conceivable.

  The main object of the present invention is to provide a diaphragm type fluid device that can suitably suppress dielectric breakdown due to charging of a diaphragm while suppressing contamination of a fluid passage or the like.

  Hereinafter, effective means for solving the above-described problems will be described while showing effects and the like as necessary. In the following, in order to facilitate understanding, a corresponding configuration example in the embodiment of the invention is appropriately shown in parentheses, etc., but is not limited to the specific configuration shown in parentheses.

Means 1. A diaphragm member (diaphragm valve body 26) is operably provided in an internal space formed inside the apparatus body, and one surface of the diaphragm member is a fluid contact surface (wetted surface) and the other surface is a non-fluid contact surface. (Non-wetted surface) In the diaphragm type fluid device that allows the fluid to be controlled to enter and exit by the operation of the diaphragm member,
A conductive layer (conductive layer 41) having a high resistance portion on the diaphragm member side and a low resistance portion on the surface side of the diaphragm member is formed on the non-fluid surface of the diaphragm member. A diaphragm type fluid device to which (earth wire E1) is connected.

  Note that the “fluid contact surface” is a surface that is in contact with the fluid to be controlled (for example, liquid), and the “fluid non-contact surface” is a surface that is not in contact with the fluid to be controlled.

  In the diaphragm type fluid device of means 1, fluid (fluid to be controlled) enters and exits as the diaphragm member operates. For example, in the case of a fluid control valve, the communication state between the inlet side passage and the outlet side passage (the opening degree of the communication portion) is controlled in accordance with the operation amount of the diaphragm member, and the fluid flows into the inlet by communicating these passages. It flows from the side passage to the exit side passage. In the case of a diaphragm pump, fluid is alternately sucked and discharged in the fluid chamber (pump chamber) in accordance with the operation of the diaphragm member. The diaphragm member is made of an insulating material such as a fluororesin.

  When a fluid (liquid or gas) is passed through the fluid passage or the like, the surface of the diaphragm may be charged by static electricity. In this case, there is a concern that charging may occur on the fluid contact surface side of the diaphragm member, and dielectric breakdown of the diaphragm member may occur due to the charging. In this respect, according to the means 1, even if charging occurs on the fluid contact surface side of the diaphragm member, the charge is released through the conductive layer and the grounding means. In this case, in particular, since the conductive layer has a high resistance on the diaphragm member side and a low resistance portion on the surface side, the current flowing from the fluid contact surface side of the diaphragm member to the non-fluid contact surface side during discharge While being restricted by the high resistance portion, the static electricity is gradually removed through the low resistance portion and the grounding means. Thereby, the dielectric breakdown of the diaphragm member is suppressed. In addition, since the conductive layer is provided on the fluid non-contact surface side of the diaphragm member and not provided on the fluid contact surface side, it is possible to avoid the inconvenience that the internal space (fluid passage, etc.) is contaminated by the elution of the conductive substance. . As a result, it is possible to suitably suppress dielectric breakdown due to charging of the diaphragm member while suppressing contamination of the fluid passage and the like.

  Mean 2. The diaphragm type fluid device according to claim 1, wherein the conductive layer is provided over the entire surface of the diaphragm member that is not in contact with the fluid.

  According to the means 2, since the conductive layer is provided over the entire surface of the diaphragm member that is not in contact with the fluid, the entire diaphragm member can be neutralized.

  Means 3. The conductive layer is formed by laminating a high resistance layer (high resistance layer 42) having a relatively high resistance and a low resistance layer (low resistance layer 43) having a lower resistance than the high resistance layer. The diaphragm type fluid device according to means 1 or 2.

  According to the means 3, the conductive layer is formed by the two resistance layers having different resistance values, and the current flowing in the thickness direction (film portion thickness direction) of the diaphragm member is limited by the high resistance layer, and the current is reduced. It can flow through the low resistance layer. In this case, the high resistance layer and the low resistance layer may be formed by adhesion or coating of a thin film body.

  Incidentally, the resistance value of the high resistance layer is desirably 1 to 100 MΩ, and the resistance value of the low resistance layer is desirably 1 kΩ or less.

  Means 4. The high resistance layer is provided over the entire surface of the diaphragm member on the fluid non-contact surface side, whereas the low resistance layer is provided on the means 3 provided on a part of the diaphragm member on the fluid non-contact surface side. The diaphragm type fluid device as described.

  According to the means 4, charges generated by charging can be appropriately eliminated while preventing dielectric breakdown of the entire diaphragm surface. In this configuration, since the low resistance layer is locally provided, the amount of the resistor material required for forming the conductive layer can be reduced.

  Means 5. The diaphragm type fluid device according to any one of means 1 to 4, wherein the low resistance portion is embedded in the high resistance portion in the conductive layer.

  According to the means 5, it is possible to provide the low resistance portion as a discharge path with a minimum necessary amount while forming the high resistance portion for limiting the current at the time of diaphragm static elimination with a sufficient size.

  Means 6. The diaphragm type fluid device according to any one of means 1 to 5, wherein the conductive layer is made of a flexible material.

  According to the means 6, in the configuration in which the conductive layer is formed on the non-fluid surface of the diaphragm member, the influence on the bending operation of the diaphragm member can be reduced. For example, an elastic material having flexibility is used.

Mean 7 A diaphragm member (diaphragm valve body 26) is operably provided in an internal space formed inside the apparatus body, and one surface of the diaphragm member is a fluid contact surface (wetted surface) and the other surface is a non-fluid contact surface. (Non-wetted surface) In the diaphragm type fluid device that allows the fluid to be controlled to enter and exit by the operation of the diaphragm member,
Insulating means (insulating spacer 51, insulating coating 52) are provided between the fluid non-contact surface of the diaphragm member and the conductive component (piston rod 16) provided on the device body so as to face the fluid non-contact surface. Diaphragm type fluid device characterized by being made.

  In the diaphragm type fluid device of means 7, like the above-described means 1, fluid (fluid to be controlled) enters and exits due to the operation of the diaphragm member, and during the operation, the surface of the diaphragm is charged by static electricity. . In this case, in the configuration in which the conductive component is provided facing the non-fluid contact surface of the diaphragm member, discharge occurs between the non-fluid contact surface and the conductive component, resulting in insulation of the diaphragm member. There is concern about the destruction. In this respect, according to the means 7, since the insulating means is provided between the non-fluid surface of the diaphragm member and the conductive part, the insulating means blocks the discharge path from the diaphragm member to the conductive part. Thus, the dielectric breakdown of the diaphragm member due to the discharge between the diaphragm member and the conductive part is suppressed. In this configuration, since no additional configuration is required on the fluid contact surface side of the diaphragm member, the inconvenience that the internal space (fluid passage or the like) is contaminated by the elution of the conductive substance can be avoided. As a result, it is possible to suitably suppress dielectric breakdown due to charging of the diaphragm member while suppressing contamination of the fluid passage and the like.

  Means 8. 8. The diaphragm type fluid device according to claim 7, wherein a sheet-like insulating spacer (insulating spacer 51) is provided as the insulating means.

  According to the means 8, it becomes possible to extend the discharge distance from the non-contact surface of the diaphragm member to the conductive component by the insulating spacer. In this case, the insulation breakdown of the diaphragm member can be prevented by extending the insulation distance.

Means 9. A diaphragm type fluid device provided by connecting a piston member (piston rod 16) made of a conductive material as the conductive component to the diaphragm member,
The insulating spacer is provided in a space between the non-fluid surface of the diaphragm member and the piston member, and a part of the spacer is sandwiched and fixed by a connecting portion between the diaphragm member and the piston member. The diaphragm type fluid device according to claim 8.

  In the configuration in which the diaphragm member and the piston member made of a conductive material are integrally connected, electric discharge occurs between the two members, and there is a possibility that dielectric breakdown of the diaphragm member occurs at that time. In this respect, according to the means 9, discharge between these two members is suppressed by the insulating spacer provided in the space between the non-fluid surface of the diaphragm member and the piston member, thereby preventing the dielectric breakdown of the diaphragm member. Can be prevented.

  Since the insulating spacer is sandwiched and fixed between the connecting portions of the diaphragm member and the piston member, the spacer and both members can always be integrated. Further, since the spacer operates together with the diaphragm member or the like, it is possible to always maintain an appropriate discharge suppression state even when the diaphragm member or the like operates.

  Means 10. 8. The diaphragm type fluid device according to claim 7, wherein an insulating coating (insulating coating 52) is formed on the surface of the conductive component facing the diaphragm member as the insulating means.

  According to the means 10, the discharge path between the diaphragm member and the conductive component is interrupted by the insulating film formed on the conductive component. Thereby, the dielectric breakdown of a diaphragm member can be prevented.

Means 11. A diaphragm type fluid device provided by connecting a piston member (piston rod 16) made of a conductive material as the conductive component to the diaphragm member,
The diaphragm type fluid device according to claim 10, wherein the insulating coating is formed on a surface of the piston member facing the non-contact surface of the diaphragm member.

  In the configuration in which the diaphragm member and the piston member made of a conductive material are integrally connected, electric discharge occurs between the two members, and there is a possibility that dielectric breakdown of the diaphragm member occurs at that time. In this respect, according to the means 11, the discharge between the two members is suppressed by the insulating film formed on the surface of the piston member facing the non-fluid contact surface of the diaphragm member, thereby preventing the dielectric breakdown of the diaphragm member. be able to.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. In the present embodiment, a liquid control valve used in a liquid supply system used in a semiconductor manufacturing apparatus or the like will be described. The fluid control valve controls the flow (in / out) of the liquid as the control target fluid.

  FIG. 1 is a cross-sectional view showing the configuration of the liquid control valve 10. In FIG. 1, the liquid control valve 10 includes a drive unit 13 including a cover 11 and a cylinder body 12 and a flow channel body 14 in which a flow channel is formed, and these are integrally coupled. The cover 11 and the cylinder body 12 are made of synthetic resin such as polypropylene, and the flow path body 14 is made of synthetic resin such as fluororesin.

  The cylinder body 12 is formed with a cylindrical sliding hole 15 penetrating from the cover 11 side to the flow path body 14 side, and a piston rod 16 is slidably accommodated in the sliding hole 15. . Specifically, the sliding hole 15 has a coaxial large diameter hole portion 15a and a small diameter hole portion 15b, and the large diameter portion 16a of the piston rod 16 is slidably accommodated in the large diameter hole portion 15a. The small-diameter portion 16b of the piston rod 16 is slidably accommodated in the small-diameter hole portion 15b.

  A spring chamber 18 is formed between the piston rod 16 and the cover 11, and a coil spring 19 is disposed in the spring chamber 18. Therefore, the piston rod 16 is always urged downward by the coil spring 19 (the direction in which a diaphragm valve body 26 described later is closed). The piston rod 16 is made of a metal material such as stainless steel or aluminum. In addition, the liquid control valve 10 can be realized other than the normally closed type as in the present embodiment, for example, a normally open type.

  A space surrounded by the piston rod 16 and the cylinder body 12 is a pressure control chamber 21, and the pressure control chamber 21 is connected to an external device (electric power not shown) via an air introduction port 22 and an air passage 23. Operation air is introduced from an empty regulator or the like. In this case, when the air pressure in the pressure control chamber 21 rises, the piston rod 16 can move (move upward in the figure) against the urging force of the coil spring 19. An annular seal member 24 is disposed on the outer periphery of the large-diameter portion 16 a and the small-diameter portion 16 b of the piston rod 16 in order to improve the airtightness of the pressure control chamber 21.

  Further, a diaphragm valve body 26 made of a synthetic resin (insulating material) such as a fluororesin is connected to the lower end portion (tip portion on the flow path body 14 side) of the piston rod 16. The diaphragm valve body 26 includes a boss portion 26a connected to the piston rod 16, a peripheral edge portion 26b sandwiched between the cylinder body 12 and the flow path body 14, and a diaphragm formed between the boss portion 26a and the peripheral edge portion 26b. And a film part 26c. The boss portion 26a is provided with a male screw portion 26d. The male screw portion 26d is screwed into the screw hole 16c of the piston rod 16, so that the piston rod 16 and the diaphragm valve body 26 are integrated. . The diaphragm valve body 26 has a wetted surface on the lower surface in the figure and a non-wetted surface on the upper surface in the figure. In addition, the intensity | strength of a screw connection part is ensured because the piston rod 16 is comprised with the metal material.

  In addition, two flow ports 31 and 32 are formed on the opposite side surface of the flow path body 14, and liquid passages 33 and 34 communicating with the ports 31 and 32 are formed. The liquid passages 33 and 34 are communicated or blocked by the operating position of the diaphragm valve body 26.

  Specifically, the liquid passage 33 communicating with one opening port 31 is formed such that the passage end on the diaphragm valve body 26 side (passage end opposite to the opening port 31) is located at the center of the flow path body 14. On the other hand, the liquid passage 34 communicating with the other opening port 32 is formed such that the passage end on the side of the diaphragm valve body 26 (passage end opposite to the opening port 32) surrounds the liquid passage 33. That is, in the liquid passage 34, the passage end on the diaphragm valve body 26 side is an annular passage. In this case, in the vicinity of the diaphragm valve body 26, a cylindrical projection 35 is formed between the liquid passage 33 and the liquid passage 34, and a tip portion (upper end portion in the drawing) of the projection 35 is connected to the valve seat 36. It has become.

  The valve seat 36 is provided in an annular shape so as to surround the opening of the liquid passage 33, and the bottom surface of the boss portion 26 a of the diaphragm valve body 26 contacts the valve seat 36. When the boss portion 26a of the diaphragm valve body 26 abuts against or separates from the valve seat 36, the flow of the liquid through the liquid passages 33 and 34 is prevented or allowed.

  Incidentally, one of the opening port 31 and the liquid passage 33 and the opening port 32 and the liquid passage 34 is the liquid inlet side and the other is the liquid outlet side.

  In the liquid control valve 10 configured as described above, when the piston rod 16 moves due to the introduction of operating air into the pressure control chamber 21 (increase in air pressure), the boss portion 26a of the diaphragm valve body 26 moves away from the valve seat 36 accordingly. The liquid flows through the gap between the boss portion 26a and the valve seat 36. In such a case, the separation distance (corresponding to the valve opening) between the boss portion 26a and the valve seat 36 is adjusted by the amount of operation air introduced into the pressure control chamber 21 (air pressure), and thereby the liquid flowing out. The pressure of is adjusted.

  By the way, in the liquid control valve 10, when the diaphragm valve body 26 is operated along with the reciprocating motion (vertical movement) of the piston rod 16, static electricity is generated due to friction between the diaphragm surface and the liquid, and the diaphragm surface is charged accordingly. When the diaphragm surface is charged, there is a concern that the dielectric breakdown of the diaphragm valve body 26 may occur due to the charging. Therefore, in the present embodiment, a conductive layer is provided on the non-wetted surface side of the diaphragm valve body 26, and charged charges are removed through the conductive layer.

  2A and 2B show an enlarged cross-sectional structure of the diaphragm valve body 26. FIG. In FIG. 2, the lower surface side of the diaphragm valve body 26 is a liquid contact surface side, and the upper surface side is a non-wetted surface side.

  As shown in FIG. 2A, a conductive layer 41 is formed on the non-wetted surface side of the diaphragm valve body 26 over the entire surface (at least the entire surface of the diaphragm film portion 26c, which is a deformed portion). The conductive layer 41 is formed by laminating a high resistance layer 42 having a relatively high resistance and a low resistance layer 43 having a resistance lower than that of the high resistance layer 42. The high resistance layer 42 is formed on the diaphragm side, The low resistance layer 43 is on the surface side (the high resistance layer 42 is in contact with the non-wetted surface of the diaphragm valve body 26). A ground member E2 is connected to the low resistance layer 43 via a ground wire E1.

  The conductive layer 41 formed on the non-wetted surface side of the diaphragm valve body 26 may be provided over at least the entire surface of the diaphragm film portion 26c, and the joint portion with the piston rod 16 and the peripheral portion 26b in the boss portion 26a. In this case, the conductive layer 41 may not be provided at the joint with the cylinder body 12.

  For example, the resistance value of the high resistance layer 42 is several MΩ, and the resistance value of the low resistance layer 43 is about several hundreds Ω. Each of the resistance layers 42 and 43 is a thin-walled conductor made of conductive rubber having conductivity and flexibility such as nitrile rubber (NBR), fluorine rubber, and the like by adhesion (attachment) or coating (film treatment). The diaphragm valve body 26 is laminated. The thicknesses of the resistance layers 42 and 43 are the same, but the low resistance layer 43 may be thinner than the high resistance layer 42. The low resistance layer 43 is desirably as thin as possible.

  Since the diaphragm valve body 26 is provided with the conductive layer 41 as described above, even if charging occurs on the liquid contact surface side of the diaphragm valve body 26, the charge is transferred to the conductive layer 41 and the grounding means (ground wire E1). And the earthing member E2).

  Specifically, as shown in FIG. 2B, the liquid contact surface side of the diaphragm valve body 26 in a state where electric charge (negative charge) is charged on the liquid contact surface of the diaphragm valve body 26 with the operation of the diaphragm valve body 26. The charge moves from the surface to the non-wetted surface side and further flows to the conductive layer 41. At this time, a high resistance layer 42 is formed on the entire non-wetted surface of the diaphragm valve body 26, and current is limited when charge flows into the high resistance layer 42. That is, a large current is suppressed from flowing in the thickness direction of the diaphragm valve body 26 (film portion thickness direction). Further, a low resistance layer 43 is laminated on the high resistance layer 42, and a current flows to the ground wire E <b> 1 side through the low resistance layer 43.

  When the diaphragm valve body 26 is discharged, the high resistance layer 42 limits the current so that the static electricity is gradually removed. Thereby, the dielectric breakdown of the diaphragm valve body 26 is suppressed.

  According to the embodiment described in detail above, the following excellent effects are obtained.

  Since the conductive layer 41 composed of the high resistance layer 42 and the low resistance layer 43 is provided on the non-wetted surface of the diaphragm valve body 26, the static electricity can be gradually removed when the diaphragm surface is charged. Dielectric breakdown can be suppressed.

  Since the conductive layer 41 is provided over the entire non-wetted surface of the diaphragm valve body 26, the entire diaphragm valve body 26 can be neutralized.

  Further, since the conductive layer 41 is provided on the non-wetted surface side of the diaphragm valve body 26 and is not provided on the wetted surface side, it is possible to avoid the inconvenience that the liquid passage or the like is contaminated by elution of the conductive substance. For example, in a semiconductor manufacturing apparatus, contamination of a semiconductor (work) can be suppressed.

  Since the conductive layer 41 is made of a material having flexibility, the influence on the bending operation of the diaphragm valve body 26 can be reduced. Thereby, suitable opening / closing control can be realized in the liquid control valve 10.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In this embodiment, an insulating spacer as an insulating means is provided between the non-wetted surface of the diaphragm valve body 26 and the piston rod 16 provided to face the non-wetted surface.

  Hereinafter, the configuration will be described with reference to FIG. The liquid control valve 10 shown in FIG. 3 has substantially the same configuration as that of FIG. 1, and in FIG. 3, the same components as those in FIG. As a difference, instead of providing the conductive layer 41 on the diaphragm valve body 26, an insulating spacer 51 is provided between the diaphragm valve body 26 and the piston rod 16.

  Specifically, a piston rod 16 made of a metal material (conductive material) is connected to the diaphragm valve body 26, and a space between the non-wetted surface of the diaphragm valve body 26 and the piston rod 16 (non-wetted surface side). An insulating spacer 51 is provided in the space S). The insulating spacer 51 is made of a disc-shaped insulating sheet, and the boss portion 26a of the diaphragm valve body 26 is inserted into the central hole portion thereof, and the periphery of the hole portion is sandwiched and fixed between the diaphragm valve body 26 and the piston rod 16. ing.

  In the liquid control valve 10 having the above-described configuration, when charging occurs on the liquid contact surface side of the diaphragm valve body 26, a discharge is generated between the non-liquid contact surface of the diaphragm valve body 26 and the piston rod 16, resulting in this. There is a concern that the dielectric breakdown of the diaphragm valve body 26 may occur. In this respect, since the insulating spacer 51 is provided, the insulating spacer 51 extends the discharge distance from the non-wetted surface of the diaphragm valve body 26 to the piston rod 16. Therefore, the dielectric breakdown of the diaphragm valve body 26 caused by the discharge between the diaphragm valve body 26 and the piston rod 16 can be suppressed.

  Since the insulating spacer 51 is sandwiched and fixed between the connecting portions of the diaphragm valve body 26 and the piston rod 16, the spacer 51 and the members 26 and 16 can be always integrated. Further, since the spacer 51 operates together with the diaphragm valve body 26 and the like, even when the diaphragm valve body 26 and the like operate, it is possible to always maintain an appropriate discharge suppression state.

  Also in the liquid control valve 10 of the present embodiment, as in the first embodiment, no additional structure is required on the liquid contact surface side of the diaphragm valve body 26 and no conductive member is provided. Therefore, it is possible to avoid the disadvantage that the liquid passage and the like are contaminated by the elution of the conductive substance. Thereby, for example, in a semiconductor manufacturing apparatus, contamination of a semiconductor (work) can be suppressed.

(Third embodiment)
Next, a third embodiment of the present invention will be described. In the present embodiment, the piston rod 16 has a configuration in which an insulating coating as an insulating means is formed on a surface facing the diaphragm valve body 26.

  The configuration will be described below with reference to FIG. The liquid control valve 10 shown in FIG. 4 has substantially the same configuration as that in FIG. 1. In FIG. 4, the same components as those in FIG. As a difference, instead of providing the conductive layer 41 on the diaphragm valve body 26, an insulating coating 52 is formed on the surface of the piston rod 16 facing the non-wetted surface of the diaphragm valve body 26. An insulating coating 52 may be formed on the entire outer surface of the piston rod 16.

  In the liquid control valve 10 having the above configuration, since the insulating coating 52 is provided, the insulating coating 52 blocks the discharge path between the diaphragm valve body 26 and the piston rod 16. Therefore, the dielectric breakdown of the diaphragm valve body 26 caused by the discharge between the diaphragm valve body 26 and the piston rod 16 can be suppressed.

  Also in the liquid control valve 10 of the present embodiment, as in the first embodiment, no additional structure is required on the liquid contact surface side of the diaphragm valve body 26 and no conductive member is provided. Therefore, it is possible to avoid the disadvantage that the liquid passage and the like are contaminated by the elution of the conductive substance. Thereby, for example, in a semiconductor manufacturing apparatus, contamination of a semiconductor (work) can be suppressed.

(Other embodiments)
The present invention is not limited to the description of the above embodiment, and may be implemented as follows, for example.

  In the first embodiment, the conductive layer 41 formed on the diaphragm valve body 26 has a two-layer structure of a high resistance layer 42 and a low resistance layer 43, and each of the resistance layers 42, 43 is formed on the entire diaphragm surface (at least The diaphragm film portion 26c is provided on the entire non-wetted surface side of the diaphragm film portion 26c, but this is changed as follows.

  (1) The conductive layer 41 is composed of three or more resistance layers having different resistance values.

  (2) The conductive layer 41 has a structure in which the resistance value is changed stepwise so that the resistance becomes higher toward the diaphragm side and becomes lower as the distance from the diaphragm (the surface side opposite to the diaphragm) decreases.

  (3) The high resistance layer 42 is provided on the entire diaphragm surface (at least the entire surface on the non-wetted surface side of the diaphragm film part 26c), whereas the low resistance layer 43 is provided on the entire diaphragm surface (at least the entire surface on the non-wetted surface side of the diaphragm film part 26c). ). For example, a radial low resistance portion or a lattice-like low resistance portion can be provided on the surface of the high resistance layer 42.

  (4) In the conductive layer 41, the low resistance layer 43 is deleted, and a low resistance portion is embedded in the high resistance layer 42.

  In any of the above (1) to (4), the dielectric breakdown of the diaphragm valve body 26 can be suitably suppressed. In short, as long as the conductive layer 41 is configured to have a high resistance on the diaphragm valve body 26 side and a low resistance on the opposite side, the desired effect can be obtained. According to (3), it is possible to reduce the amount of the resistor material required for forming the conductive layer 41 while preventing the dielectric breakdown of the entire diaphragm. Moreover, according to (4), the low resistance part which is a discharge path | route can be provided in the minimum necessary while forming the high resistance part for performing the electric current restriction | limiting at the time of diaphragm static elimination with sufficient magnitude | size.

  In the second and third embodiments, the insulating means (insulating spacer 51, insulating coating 52) is provided between the piston rod 16 and this is changed to face the non-wetted surface of the diaphragm valve body 26. When there is a part other than the piston rod 16 as the conductive part to be performed, an insulating means is provided between the other part.

  In each of the above embodiments, the subject of the invention is the liquid control valve, but this can be changed to a diaphragm pump. In the case of a diaphragm pump, a pump chamber for sucking liquid is formed, and a diaphragm member is provided so that one surface thereof is in contact with the pump chamber. The volume of the pump chamber is expanded or reduced by the operation of the diaphragm member, and the suction and discharge of the liquid are alternately performed. That is, the liquid is sucked into the pump chamber as the volume of the pump chamber is expanded by the operation of the diaphragm member, and conversely, the liquid in the pump chamber is reduced as the volume of the pump chamber is reduced by the operation of the diaphragm member. Is discharged. Even in the case of such a diaphragm pump, charging may occur on the surface of the diaphragm, but by providing the conductive layer as described above on the surface (non-wetted surface), it is possible to suppress the dielectric breakdown of the diaphragm member. .

  In each of the embodiments described above, the specific configuration of the liquid control device that uses the fluid to be controlled as a liquid and circulates the liquid has been described, but instead, the gas as the fluid to be controlled and the gas that circulates the gas. A control device can also be embodied. For example, examples of the gas to be controlled include dry air and nitrogen gas (N2 gas). Even in the case of a gas control valve or a gas pump that uses a fluid to be controlled as a gas, the dielectric breakdown of the diaphragm member can be suitably suppressed as described above.

Sectional drawing which shows the structure of the liquid control valve in 1st Embodiment. Sectional drawing which expands and shows the cross-section of a diaphragm valve body. Sectional drawing which shows the structure of the liquid control valve in 2nd Embodiment. Sectional drawing which shows the structure of the liquid control valve in 3rd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Liquid control valve (diaphragm type fluid equipment), 16 ... Piston rod (electroconductive part), 26 ... Diaphragm valve body (diaphragm member), 41 ... Conductive layer, 42 ... High resistance layer, 43 ... Low resistance layer, 51 Insulating spacer 52 Insulating coating E1 Ground wire (grounding means) E2 Grounding member (grounding means)

Claims (11)

A diaphragm member is operably provided in an internal space formed inside the device body, and one surface of the diaphragm member is a fluid contact surface and the other surface is a fluid non-contact surface. In a diaphragm type fluid device that allows fluid to enter and exit,
A conductive layer having a high resistance portion on the diaphragm member side and a low resistance portion on the surface side is formed on the non-fluid surface of the diaphragm member, and a grounding means is connected to the conductive layer. A diaphragm-type fluid device characterized by   The diaphragm type fluid device according to claim 1, wherein the conductive layer is provided over the entire surface of the diaphragm member that is not in contact with the fluid.   The diaphragm type fluid device according to claim 1, wherein the conductive layer is configured by laminating a high resistance layer having a relatively high resistance and a low resistance layer having a lower resistance than the high resistance layer. .   The high resistance layer is provided over the entire surface of the diaphragm member on the fluid non-contact surface side, whereas the low resistance layer is provided on a portion of the diaphragm member on the fluid non-contact surface side. The diaphragm type fluid device described in 1.   The diaphragm type fluid device according to any one of claims 1 to 4, wherein in the conductive layer, the low resistance portion is embedded in the high resistance portion.   The diaphragm type fluid device according to any one of claims 1 to 5, wherein the conductive layer is made of a flexible material. A diaphragm member is operably provided in an internal space formed inside the device body, and one surface of the diaphragm member is a fluid contact surface and the other surface is a fluid non-contact surface. In a diaphragm type fluid device that allows fluid to enter and exit,
A diaphragm type fluid device, wherein an insulating means is provided between a fluid non-contact surface of the diaphragm member and a conductive component provided in the device main body so as to face the fluid non-contact surface.   The diaphragm type fluid device according to claim 7, wherein a sheet-like insulating spacer is provided as the insulating means. A diaphragm type fluid device provided by connecting a piston member made of a conductive material as the conductive component to the diaphragm member,
The insulating spacer is provided in a space between the non-fluid surface of the diaphragm member and the piston member, and a part of the spacer is sandwiched and fixed by a connecting portion between the diaphragm member and the piston member. The diaphragm type fluid device according to claim 8.   The diaphragm type fluid device according to claim 7, wherein an insulating coating is formed on the surface of the conductive component facing the diaphragm member as the insulating means. A diaphragm type fluid device provided by connecting a piston member made of a conductive material as the conductive component to the diaphragm member,
The diaphragm type fluid device according to claim 10, wherein the insulating coating is formed on a surface of the piston member facing the non-contact surface of the diaphragm member.

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