JP3404265B2 - solenoid valve - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic valve, and more particularly to an electromagnetic valve used for controlling a gas flow path of an analyzer and a gas supply control of a semiconductor manufacturing apparatus. 2. Description of the Related Art In controlling a gas flow path of a gas analyzer, a gas sampling apparatus, or the like, the flow of gas in a flow path is switched by using an electromagnetic valve provided in a flow path switching section. Also, in a semiconductor manufacturing apparatus, the control of gas supply of a high-temperature gas is performed using an electromagnetic valve. In general, an electromagnetic valve includes a valve that opens and closes a flow path and a solenoid that electromagnetically drives the valve, and controls the gas flowing through the flow path by opening and closing the valve with the solenoid. Conventionally, a coil winding constituting a solenoid is formed by aligning and winding a magnet wire. 8 to 10 are sectional views of a solenoid for explaining a conventional coil winding. In the coil winding shown in FIG. 8, a magnet wire 40 is arranged and wound around the coil core 17, then impregnated with a fixed varnish 52, and an outer tape 53 is wound around the outer periphery.
External conductor 3 at the end of the magnet wire at the beginning and end of winding
1 is formed by soldering. At this time, solder 5
The insulation between 1 and the exterior tape 53 is performed by the insulating paper 50. The coil winding shown in FIG. 9 is formed by sandwiching an interlayer insulating paper 50 between the magnet wires each time the magnet wires are further aligned and wound in the coil winding shown in FIG. With the coil winding having this configuration, good interlayer insulation can be obtained, but the number of turns is reduced within the same coil core dimensions, and the temperature rise and magnetomotive force of the coil are limited, which is disadvantageous in terms of space. Becomes The coil winding shown in FIG.
Are aligned and filled with resin 55 using a predetermined mold,
It is to be cured. As the resin, an epoxy resin can be mainly used. [0006] In the gas collecting apparatus, if another gas component is mixed with the collected gas component, the mixed gas component becomes an interfering component at the time of component concentration analysis, resulting in an error in the analysis result. Causes, and also in the semiconductor manufacturing equipment, if other gas components are mixed in the supply gas,
This gas component becomes an interfering component, which does not satisfy the set conditions for semiconductor manufacturing, and causes impurities to be mixed into the manufactured semiconductor product. Hitherto, as a wire outer coating material provided on the outer periphery of a high-temperature magnet wire used for an electromagnetic valve or the like, a polyester, polyamide-based, or polyimide-based material has been used as an insulating material. , An organic gas component is generated, which has an adverse effect on organic gas analysis. [0008] Further, a solenoid valve conventionally used is a binder material for fixing a coil winding of a solenoid.
An adhesive tape containing an organic solvent or a silicone resin-based or epoxy resin-based adhesive is used. For example, the varnish uses a material obtained by dissolving a silicon-based adhesive with an organic solvent, and the resin is a substance requiring an organic solvent such as epoxy and phenol. Therefore, if various organic solvent components such as heptane, acetone, hexane, butanol, and xylene contained in these adhesive members are mixed into the flow path system of the solenoid valve, the analysis results and the semiconductor will be adversely affected.
In particular, when the solenoid valve is used at a high temperature of 100 ° C. or more, a large amount of organic solvent components are generated, and the influence on the analysis result and the semiconductor is increased. Further, when an organic material is used, P.I. P. Except for special new materials such as S and PEEK, there is also a limit on the operating temperature, and complete stabilization of Class C insulation (230 ° C or more) specified by JIS requires only organic materials. Have difficulty. Further, ceramic materials, glass-based binder materials, and silicon-based binder materials are known as binder materials. However, Na-based ceramic materials may not be applicable to semiconductor manufacturing equipment because Na ions may be generated at high temperatures, and glass-based binder materials are likely to react with chemical substances and have a stable passive state. Therefore, there is a possibility that an ion-based gas may be generated, and since the silicon-based binder is not passive, an inorganic gas may be generated at a high temperature. In addition, since the membrane quality of a diaphragm valve used in a conventional solenoid valve has pores, an interfering component penetrates from the coil winding side to the flow path side through the membrane, and adversely affects the analysis result and the semiconductor. become. Furthermore, since the inside of the flow passage provided in the conventional solenoid valve has irregularities formed by processing at the time of forming the passage, the gas component tends to be adsorbed and adhered to the irregularities and remain. The remaining gas component may be mixed as an interfering component and adversely affect the analysis result or the semiconductor. As described above, in the conventional solenoid valve, there is a possibility that an interfering gas may enter the flow passage depending on the material and structure forming the solenoid valve, which has a problem of adversely affecting the analysis result and the semiconductor. There is. Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide an electromagnetic valve capable of reducing the intrusion of an interfering gas into a flow path. According to the present invention, there is provided an electromagnetic valve in which a metal or an inorganic material containing no organic component is used for a member constituting an electromagnetic valve, and an elastic synthetic resin which generates little organic component gas is used for a diaphragm. The use reduces the intrusion of organic components into the flow channel, thereby preventing an adverse effect on an analyzer using a solenoid valve and a semiconductor manufacturing apparatus. Therefore, the solenoid valve of the present invention is a solenoid valve comprising a diaphragm movably provided in a flow path and a solenoid for applying a movable force to the diaphragm, wherein the solenoid is a coil forming the solenoid. Coating and insulation and fixing between the windings is performed by a fixing member made of an inorganic material having chemical passivation, and the diaphragm has a low porosity and a low generation rate of an organic component gas such as polytetrafluoroethylene. A thick film is formed of an elastic synthetic resin, and the flow path has a configuration in which a base is formed of a metal material having a thermal expansion coefficient equivalent to that of a pipe member connected to the flow path. According to the above configuration, the solenoid is formed by using a chemically passive inorganic material as a coating material and a fixing member to form a coil winding, and by performing insulation and fixing, an organic material at the solenoid portion is formed. The generation of component gas components can be eliminated. In the embodiment of the present invention, a stable fine ceramic material that does not generate gas can be used as the material of the chemically passivated inorganic material. In the embodiment of the present invention, a winding process is performed in which a coil is wound one by one while applying a fine ceramic material to a magnet wire, so that a film is formed on the outer periphery of the winding and a fine ceramic material is formed between the windings. To form an insulating layer. Further, in the embodiment of the present invention, the outside of the wound coil can be covered with a fine ceramic material and fixed together with the external conductor. Further, in the embodiment of the present invention, a glass fiber tape and a ceramic adhesive can be used in combination as a fixing member made of an inorganic material. Can be temporarily fixed, and the coil winding can be fixed and the solenoid valve can be fixed to the body by the adhesive of the ceramic material. Another embodiment of the present invention is to form an insulating film of TFE (tetrafluoroethylene) on a coil winding and an external conductor connected to the coil winding, thereby forming an organic component. Gas generation can be reduced. Further, the diaphragm is made of a material having low porosity and low permeability and is formed to have a large film thickness so that organic component gas entering from the solenoid side to the flow path side through the membrane portion can be reduced. By using a material having a low generation rate of the organic component gas, it is possible to reduce the intrusion of the organic component gas into the flow path. In another embodiment of the present invention, PTFE (polytetrafluoroethylene) is used as a synthetic resin for forming a diaphragm, whereby the generation of an organic component gas can be reduced. Further, the flow path is formed of a metal base so that generation of organic component gas can be eliminated. Further, by using a pipe having a coefficient of thermal expansion equivalent to that of a pipe member connected to the flow path, temperature can be reduced. The occurrence of a gap at the joint due to the difference can be reduced, and the intrusion of the organic component gas through the gap can be reduced. Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a partially cutaway perspective view for explaining the configuration of the solenoid valve of the present invention.
FIG. 2 is a sectional view of a solenoid of the solenoid valve according to the present invention, and FIG. 3 is a view for explaining formation of a coil winding of the solenoid. FIGS. 4 and 5 are a perspective view and a cross-sectional view for explaining the configuration of the flow path and the diaphragm of the solenoid valve according to the present invention. In FIG. 1, a solenoid valve 1 includes a diaphragm 10 movably provided in flow paths 3 and 4, and a solenoid 11 connected to apply a movable force to the diaphragm 10. Formed by storing in First, the configuration and forming process of the solenoid 11 will be described with reference to FIGS.
The solenoid 11 includes a plunger 12 for applying a movable force to the diaphragm 10, a coil winding 15 for driving the plunger 12, and a spring member 14. The plunger 12 is formed of a magnetic material or a permanent magnet, and has a rod 23 at one end for connecting to the diaphragm 10 and a rod 13 for attaching the spring member 14 at the other end.
Is provided. A coil core 17 is provided at an interval outside the plunger 12, and the coil winding 1 is attached to the coil core 17.
5 is wound to form an electromagnet. The electromagnet generated by the coil winding 15 generates an electromagnetic force, and thereby attracts or rejects the plunger 12 disposed inside. Also,
The rod 13 is provided with a spring member 14 for urging the plunger 12 in one direction. The directions of the forces acting on the plunger 12 by the coil winding 15 and the spring member 14 are opposite to each other. In one operation example, a current is supplied to the coil winding 15 to suck the plunger 12, thereby opening the diaphragm 10. When the current stops, the plunger 12 is pushed in the opposite direction by the spring member 14 to move the diaphragm 10. Perform closing operation. In another operation example, the current is supplied to the coil winding 15 and the plunger 12
By this, the closing operation of the diaphragm 10 is performed, and when the current is stopped, the plunger 12 is returned to the opposite direction by the spring member 14 to perform the opening operation of the diaphragm 10. In the sectional view of the solenoid shown in FIG. 2, the coil winding 15 of the solenoid 11 is covered with a passive material which does not cause a chemical reaction even at a high temperature, and is wound around a coil core 17. An insulating material is provided between each layer of the wound coil winding 15. Insulating fixing binder material 18 shown in FIG.
Performs insulation between the coil windings 15 and fills and fixes the space between the coil windings 15 to serve as a so-called binder material. An outer peripheral portion of the coil winding 15 is fixed by a fixing member 19. A coating covering the outer peripheral surface of the coil winding 15;
The insulating fixing binder material 18 and the fixing material 19 are materials such as fine ceramics having a passivation property and exhibiting a stable surface state that is not affected by a chemical reaction. For example, aluminum-zirconia ceramic materials are used. Certain ceramic cements or zirconium cements can be used. In FIG. 1, the insulating fixing binder material 18 and the fixing material 19 show only the installation positions, and the respective materials are not shown. In FIG. 3, the coil winding is formed by pulling out the magnet wire 40 wound on the magnet wire drum 41 and passing the liquid fine ceramic material such as ceramic cement 43 through the surface of the magnet wire 40. Then, a fine ceramic material is applied to form a coil winding 15 having a coil winding film 44 formed thereon. The coil winding 15 coated with the fine ceramic material is wound and hardened one by one on a coil winding drum 42 such as the coil core 17 and subjected to a hardening treatment. At this time, the applied fine ceramic material forms a film, furthermore, fills a gap between the layers of the coil winding to form an insulating layer and also serves as a fixing binder for fixing the coil winding. The outer peripheral surface of the wound coil winding 15 is fixed with a fixing member 19. For the fixing member 19, the same fine ceramic material as described above can be used. Further, the fixed coil winding 15 is fixed to the coil winding 15.
May be wound around with a glass fiber tape 16 and impregnated with an insulating fixing binder material to be fixed. Both ends of the coil winding 15 are connected to the external conductor 31 by metal caulking fittings 32, and the external conductor 31 is taken out through an opening 34 opened in the body 2. The fixing of the coil winding 15 and the external conductor 31 to the body 2 can be performed by a ceramic adhesive 33. In addition, as the external conductor 31, an electric wire coated with PTFE can be used. As described above, by fixing the coil winding and the external conductor using an inorganic material such as a ceramic adhesive or a glass fiber tape, it is possible to prevent the generation of organic component gas. The coil winding 15 and the external conductor 31
Of TFE (tetrafluoroethylene) or PTF
Insulation coating with a synthetic resin having a low generation rate of an organic component gas such as E (polytetrafluoroethylene) can reduce the generation of an organic component gas. Next, the construction of the diaphragm and the flow path will be described with reference to FIGS. The diaphragm 10 has an edge portion 21 having an outer diameter that can be accommodated inside the concave portion 20 and a conical film portion 22 inclined inward from the edge portion 21 and has a low porosity. It is formed of a resilient synthetic resin such as PTFE (polytetrafluoroethylene), which has a low permeability and a low generation rate of an organic component gas. Membrane part 22 of diaphragm 10
Is formed to be as thick as, for example, about 0.35 mm, whereby the amount of organic component gas entering the flow path from the solenoid side through the film portion 22 can be reduced. A rod 23 is formed vertically on one surface of the center of the membrane portion 22 of the diaphragm 10.
Is connected to the plunger 12 on the solenoid 11 side. The other surface at the center of the film portion 22 faces the first orifice 7. The plunger 12 moves the membrane unit 22 up and down. When the plunger 12 is at the upper position, a gap is formed between the membrane 22 and the first orifice 7 to allow the gas flow to pass, and the plunger 12 moves downward. When in position, the membrane 22 blocks the first orifice 7 and stops gas flow. Note that a gap can always be formed between the second orifice 8 and the film 22. Next, the flow path will be described. The first flow path 3 and the second flow path 4 are formed by a base 2 that forms a part of the body 2.
A diaphragm 10 is movably provided in a concave portion 20 formed by a through hole in a and formed between both flow paths 3 and 4. A first connection port 5 is formed at an end of the first flow path 3 connected to the outside, and a first orifice 7 is formed at the other end on the diaphragm 10 side to penetrate the recess 20. Also, the second
A second joint opening 6 is formed at an end of the flow path 4 which is connected to the outside, and a second orifice 8 is formed at the other end on the diaphragm 10 side to penetrate the recess 20. With the above configuration, the first flow path 3 and the second flow path 4 communicate with each other through the recess 20. The gas flow flows through the flow paths 3 and 4, and the on / off control of the passage and stop of the gas flow can be performed by opening and closing the orifice of the flow path by the diaphragm 10. The channels 3 and 4 can be formed by providing through holes in the metal base 2a. By forming the base 2a of a metal, generation of an organic component gas can be prevented. In addition, the use of metal allows polishing of the inside of the flow path, thereby reducing unevenness on the inner surface of the flow path and reducing adhesion of gas components. Further, by using metal, the coefficient of thermal expansion can be made equal to that of the metal pipe member connected to the solenoid valve 1, and the gap between the base and the pipe member caused by the temperature difference can be reduced to reduce the organic pressure. Component gas intrusion can be reduced. The rod 13 formed on the body 2
The side opening is closed by a top lid 9. Next, the operation of the diaphragm of the solenoid valve will be described with reference to FIG. FIG. 5A shows a state where the flow path is closed by the diaphragm, and FIG. 5B shows a state where the flow path is opened. The edge 21 of the diaphragm 10 is fixed between the base 2a and the body 2b, and the membrane 22 is in a movable state. In this state, when an external force is applied to the diaphragm 10 by a plunger or a spring member, the membrane 22
Is deformed by its elasticity, and the distance between the contact portion 24 of the film portion 22 and the first orifice 7 changes. The space between the second orifice 8 and the membrane portion 22 is maintained at an interval regardless of the movement of the plunger. In FIG. 5A, when the plunger is moved in the direction of arrow A, the diaphragm membrane portion 22 approaches the first orifice 7, and the contact portion 24 closes the first orifice 7. Thereby, the first flow path 3 and the second flow path 4
Is shut off by the diaphragm 10, and the flow of gas is stopped by the solenoid valve. In FIG. 5B, when the plunger is moved in the direction of arrow B, the diaphragm 2 of the diaphragm is moved.
2 is separated from the first orifice 7, and a gap is formed between the contact portion 24 and the first orifice 7. by this,
Between the first flow path 3 and the second flow path 4 is in a penetrating state,
Gas flow is performed by the solenoid valve. Hereinafter, a comparison of the effect between the embodiment using the solenoid valve of the present invention and a conventional solenoid valve will be described with reference to FIGS. 6 and 7 show, by gas chromatography, the amount of organic component gas detected in the flow path through the diaphragm with respect to the organic gas generated outside the flow path, and FIG. 6 shows the diaphragm of the solenoid valve of the present invention. FIG. 7 shows the case of a diaphragm of a conventional solenoid valve. In the result of detection by the conventional solenoid valve shown in FIG. 7, a large amount of organic component gases such as ethylenebenzene, 1,2-dimethylbenzene, and dimethylbenzene are detected. In the detection result by the solenoid valve, the corresponding organic component gas is hardly detected. The scale of the peaks in FIGS. 6 and 7 is approximately 1: 150. Accordingly, the comparison between FIGS. 6 and 7 shows that the configuration of the diaphragm of the solenoid valve of the present invention significantly reduces the intrusion of the organic component gas into the flow path. According to the embodiment of the solenoid valve of the present invention, the material of the member constituting the solenoid valve is made of an inorganic material or a synthetic resin that generates little organic component gas, so that the generation of interference components is reduced, An adverse effect on the apparatus and the semiconductor manufacturing apparatus can be reduced. According to the embodiment of the solenoid valve of the present invention, the infiltration of gas into the flow passage can be reduced by making the diaphragm thicker. According to the embodiment of the solenoid valve of the present invention, the difference in the coefficient of thermal expansion between the base and the connecting pipe is made small, so that the gap formed at the joint is reduced, and Gas can be reduced. Further, according to the embodiment of the solenoid valve of the present invention, the amount of residual gas can be reduced by reducing the unevenness on the inner surface of the flow passage by polishing. Thereby, the disturbance to the concentration change in the repeated use of the rich gas and the thin gas is reduced, and the gas gas opening / closing control of the trace gas can be always performed in a state where the mixed components are small. As described above, according to the solenoid valve of the present invention, the intrusion of interfering gas into the flow path can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially cutaway perspective view for explaining a configuration of an electromagnetic valve of the present invention. FIG. 2 is a sectional view of a solenoid of the solenoid valve according to the present invention. FIG. 3 is a view for explaining formation of a coil winding of the solenoid of the present invention. FIG. 4 is a perspective view for explaining a configuration of a flow path and a diaphragm of the solenoid valve of the present invention. FIG. 5 is a view for explaining the operation of the diaphragm of the solenoid valve of the present invention. FIG. 6 is a chromatogram of a detection gas using the solenoid valve of the present invention. FIG. 7 is a chromatogram of a detection gas using a conventional solenoid valve. FIG. 8 is a sectional view of a solenoid for explaining a conventional coil winding. FIG. 9 is a sectional view of a solenoid for explaining a conventional coil winding. FIG. 10 is a sectional view of a solenoid for explaining a conventional coil winding. [Description of Signs] 1 ... solenoid valve, 2 ... body, 3, 4 ... flow path, 5, 6 ... joint opening, 7, 8 ... orifice, 9 ... top lid, 10 ... diaphragm, 11 ... solenoid, 12 ... plunger , 13,
23 ... Rod, 14 ... Spring member, 15 ... Wound coil, 1
6: glass fiber tape, 17: coil core, 18: insulating binder material, 19: fixing material, 20: recess, 21 ...
Edge part, 22 ... film part, 24 ... contact part, 31 ... external conductor, 3
Reference numeral 2: caulking fitting, 33: ceramic adhesive, 34: opening, 40: magnet wire, 41: magnet wire drum, 42: coil winding drum, 43: ceramic cement, 44: coil winding coating.

──────────────────────────────────────────────────続 き Continued from the front page (56) References JP-A-51-147759 (JP, A) JP-A-7-174259 (JP, A) JP-A-47-32422 (JP, A) 53974 (JP, U) Hira 6-71979 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16K 31/06-31/11 F16K 27/00 H01F 7/16

Claims (1)

(57) [Claim 1] A solenoid valve comprising a diaphragm movably provided in a flow path and a solenoid for applying a movable force to the diaphragm, wherein the solenoid constitutes the solenoid The coating of the winding to be formed and the insulation and fixing between the windings are performed by a fixing member made of an inorganic material having chemical passivation, and the diaphragm has a low porosity and a low polytetrafluorocarbon generation rate of an organic component gas. An electromagnetic valve, wherein the base is formed of a metal material having a thermal expansion coefficient equivalent to that of a pipe member connected to the flow channel, the base being formed in a thick film with fluoroethylene.