Diaphragm valve

Abstract

To allow a diaphragm to be firmly fixed to a flow passage side body by a diaphragm retainer, reduce a thickness of the flow passage side body on an outer peripheral part of the diaphragm, and thereby downsize the flow passage side body.SOLUTION: A diaphragm retainer contact surface 75 is formed between a diaphragm retainer inner peripheral side ring-shaped convex part 73 and a diaphragm retainer outer peripheral side ring-shaped convex part 74. A diaphragm retainer inner peripheral side end surface 73s of the diaphragm retainer inner peripheral side ring-shaped convex part 73 is brought into contact with a first fixed part piston side end surface 63Ap. A diaphragm retainer inner peripheral side outer peripheral surface 73o of the diaphragm retainer inner peripheral side ring-shaped convex part 73 is brought into contact with a second fixed part inner peripheral surface 63Bi. A diaphragm retainer outer peripheral side inner peripheral surface 74i of the diaphragm retainer outer peripheral side ring-shaped convex part 74 is brought into contact with a body side convex part outer peripheral surface 16o of a body side ring-shaped convex part 16. The diaphragm retainer contact surface 75 is brought into contact with a second fixed part piston side end surface 63Bp and a body side convex part end surface 16s of the body side ring-shaped convex part 16.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a diaphragm valve used in the cleaning and stripping processes in a silicon wafer process that often uses highly corrosive chemical solutions such as strong acids and strong alkalis.

Background Art

[0002] As disclosed in, for example, Patent Document 1, in a diaphragm valve, a diaphragm is disposed on one end side of a piston, and the diaphragm has a film portion and a fixing portion formed on the outer periphery of the film portion. In the diaphragm valve of Patent Document 1, the protruding portion of the body and the fixing portion of the diaphragm are welded, and the fixing portion is pressed into the body by a diaphragm retainer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the method described in Patent Document 1 has a problem that the manufacturing process increases because welded parts are fitted and welded by these welded parts.

[0005] Therefore, an object of the present invention is to provide a diaphragm valve that can firmly fix a diaphragm to a flow path side body by a diaphragm retainer, and can reduce the thickness of the flow path side body at the outer peripheral portion of the diaphragm or eliminate the need to provide a thickness, thereby realizing miniaturization of the flow path side body.

Means for Solving the Problems

[0006] The diaphragm valve 1 of the present invention according to claim 1 has a flow path side body 10 that forms an inflow flow path 11, an outflow flow path 12, and a valve seat 13, a drive side body 20 that internally arranges a piston 30 that moves a valve body 40 with respect to the valve seat 13, and a diaphragm 60 that is arranged on one end side of the piston 30. The diaphragm 60 has a thick portion 61 connected to the piston 30, a film portion 62 formed on the outer periphery of the thick portion 61, and a fixing portion 63 formed on the outer periphery of the film portion 62. The fixing portion 63 has a first fixing portion 63A located on the film portion 62 side and a second fixing portion 63B located on the outer periphery of the first fixing portion 63A. The first fixing portion 63A forms a first fixing portion piston side end face 63Ap on the piston 30 side and a first fixing portion valve body side end face 63Ab on the valve body 40 side. The second fixing portion 63B forms a second fixing portion piston side end face 63Bp on the piston 30 side and a second fixing portion valve body side end face 63Bb on the valve body 40 side, and forms a second fixing portion inner peripheral surface 63Bi on the inner peripheral side and a second fixing portion outer peripheral surface 63Bo on the outer peripheral side. The diaphragm valve 1 attaches the fixing portion 63 to the flow path side body 10 by a diaphragm retainer 70. The flow path side body 10 has a body side first end face 15 that abuts the first fixing portion valve body side end face 63Ab and the second fixing portion valve body side end face 63Bb, and a body side ring-shaped convex portion 16 that forms a body side convex portion inner peripheral surface 16i that abuts the second fixing portion outer peripheral surface 63Bo. The diaphragm retainer 70 has a diaphragm retainer inner peripheral side ring-shaped convex portion 73 and a diaphragm retainer outer peripheral side ring-shaped convex portion 74 located on the outer periphery of the diaphragm retainer inner peripheral side ring-shaped convex portion 73. A diaphragm retainer contact surface 75 is formed between the diaphragm retainer inner peripheral side ring-shaped convex portion 73 and the diaphragm retainer outer peripheral side ring-shaped convex portion 74. The diaphragm retainer inner peripheral side end face 73s of the diaphragm retainer inner peripheral side ring-shaped convex portion 73 abuts the first fixing portion piston side end face 63Ap, the diaphragm retainer inner peripheral side outer peripheral surface 73o of the diaphragm retainer inner peripheral side ring-shaped convex portion 73 abuts the second fixing portion inner peripheral surface 63Bi, and the diaphragm retainer outer peripheral side inner peripheral surface 74i of the diaphragm retainer outer peripheral side ring-shaped convex portion 74 abuts the body side convex portion outer peripheral surface 16o of the body side ring-shaped convex portion 16. The diaphragm pressing contact surface 75 is a single-height identical plane surrounded by the diaphragm pressing inner peripheral side ring-shaped convex portion 73 and the diaphragm pressing outer peripheral side ring-shaped convex portion 74, and extending from the diaphragm pressing outer peripheral side inner peripheral surface 74i to the diaphragm pressing inner peripheral side outer peripheral surface 73o. The diaphragm press contact surface 75 is brought into contact with the piston-side end surface 63Bp of the second fixing part and the body-side convex part end surface 16s of the body-side ring-shaped convex part 16 of the body. The invention according to claim 2 is the diaphragm valve 1 according to claim 1, wherein the inner peripheral side ring-shaped convex part 73 and the outer peripheral side ring-shaped convex part 74 of the diaphragm presser are press-fitted to the body-side ring-shaped convex part 16 and the second fixing part 63B. The invention according to claim 3 is the diaphragm valve 1 according to claim 2, wherein a second fixing part chamfered part 63c is formed at the boundary between the inner peripheral surface 63Bi of the second fixing part and the piston-side end surface 63Bp of the second fixing part. A diaphragm presser inner peripheral side chamfered part 73c is formed at the boundary between the outer peripheral surface 73o of the inner peripheral side of the diaphragm presser and the end surface 73s of the inner peripheral side of the diaphragm presser. The invention according to claim 4 is the diaphragm valve 1 according to any one of claims 1 to 3, wherein the diaphragm presser 70 is made of a material having a higher mechanical strength than the diaphragm 60 and the flow path side body 10. The invention according to claim 5 is the diaphragm valve 1 according to any one of claims 1 to 4, wherein the diaphragm 60 and the valve body 40 are made of PTFE or PFA, and the diaphragm presser 70 is made of a fluororesin such as PVdF, a thermoplastic resin such as PPS or PP, or a composite material in which glass or carbon is mixed with a thermoplastic resin. The invention according to claim 6 is the diaphragm valve 1 according to any one of claims 1 to 5, wherein the diaphragm presser 70 is sandwiched between the flow path side body 10 and the drive side body 20, and a sliding surface 71 for sliding the piston 30 is formed at the center of the diaphragm presser 70.

Advantages of the Invention

[0007] According to the diaphragm valve of the present invention, by bringing the end face on the inner peripheral side of the diaphragm retainer ring-shaped convex portion into contact with the end face on the piston side of the first fixing portion, bringing the outer peripheral surface on the inner peripheral side of the diaphragm retainer ring-shaped convex portion into contact with the inner peripheral surface of the second fixing portion, bringing the inner peripheral surface on the outer peripheral side of the diaphragm retainer ring-shaped convex portion into contact with the outer peripheral surface of the convex portion on the body side of the body-side ring-shaped convex portion, and bringing the contact surface of the diaphragm retainer into contact with the end face on the piston side of the second fixing portion and the end face of the convex portion on the body side of the body-side ring-shaped convex portion, the diaphragm can be firmly fixed to the flow path-side body by the diaphragm retainer. Further, by sandwiching the fixing portion and the body-side ring-shaped convex portion with the diaphragm retainer, the diaphragm can be firmly attached to the flow path-side body. Since the outer wall thickness of the body-side ring-shaped convex portion does not affect the attachment of the diaphragm, it is not necessary to reduce or provide a wall thickness of the flow path-side body at the outer peripheral portion of the diaphragm, and miniaturization of the flow path-side body can be achieved.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0009] The diaphragm valve according to the first embodiment of the present invention has, on the flow path side body, a body-side first end face that abuts the first fixed part valve body-side end face and the second fixed part valve body-side end face, and a body-side ring-shaped convex part that forms an inner peripheral surface of a body-side convex part that abuts the outer peripheral surface of the second fixed part. The diaphragm retainer has an inner peripheral side ring-shaped convex part of the diaphragm retainer and an outer peripheral side ring-shaped convex part of the diaphragm retainer that is located on the outer periphery of the inner peripheral side ring-shaped convex part of the diaphragm retainer. Between the inner peripheral side ring-shaped convex part of the diaphragm retainer and the outer peripheral side ring-shaped convex part of the diaphragm retainer, a diaphragm retainer contact surface is formed. The inner peripheral side end face of the inner peripheral side ring-shaped convex part of the diaphragm retainer is brought into contact with the piston side end face of the first fixed part, the outer peripheral surface of the inner peripheral side ring-shaped convex part of the diaphragm retainer is brought into contact with the inner peripheral surface of the second fixed part, the inner peripheral surface of the outer peripheral side ring-shaped convex part of the diaphragm retainer is brought into contact with the outer peripheral surface of the body-side convex part of the body-side ring-shaped convex part, and the diaphragm retainer contact surface is brought into contact with the piston side end face of the second fixed part and the body-side convex part end face of the body-side ring-shaped convex part. According to the present embodiment, by bringing the inner peripheral side end face of the inner peripheral side ring-shaped convex part of the diaphragm retainer into contact with the piston side end face of the first fixed part, bringing the outer peripheral surface of the inner peripheral side ring-shaped convex part of the diaphragm retainer into contact with the inner peripheral surface of the second fixed part, and bringing the inner peripheral surface of the outer peripheral side ring-shaped convex part of the diaphragm retainer into contact with the outer peripheral surface of the body-side convex part of the body-side ring-shaped convex part, The diaphragm pressing contact surface is a single-height identical plane surrounded by the diaphragm pressing inner peripheral side ring-shaped convex portion and the diaphragm pressing outer peripheral side ring-shaped convex portion, and extending from the diaphragm pressing outer peripheral side inner peripheral surface to the diaphragm pressing inner peripheral side outer peripheral surface. by bringing the diaphragm retainer contact surface into contact with the piston side end face of the second fixed part and the body-side convex part end face of the body-side ring-shaped convex part, the diaphragm can be firmly fixed to the flow path side body by the diaphragm retainer. Further, according to the present embodiment, by sandwiching the fixed part and the body-side ring-shaped convex part with the diaphragm retainer, the diaphragm can be firmly attached to the flow path side body. Since the outer wall thickness of the body-side ring-shaped convex part does not affect the attachment of the diaphragm, it is not necessary to reduce or provide the wall thickness of the flow path side body at the outer peripheral part of the diaphragm, and miniaturization of the flow path side body can be achieved.

[0010] The second embodiment of the present invention is a diaphragm valve according to the first embodiment, in which a ring-shaped convex portion on the inner peripheral side of the diaphragm retainer and a ring-shaped convex portion on the outer peripheral side of the diaphragm retainer are press-fitted to the body-side ring-shaped convex portion and the second fixing portion. According to this embodiment, by press-fitting the ring-shaped convex portion on the inner peripheral side of the diaphragm retainer and the ring-shaped convex portion on the outer peripheral side of the diaphragm retainer to the body-side ring-shaped convex portion and the second fixing portion, the diaphragm can be more firmly attached to the flow path side body.

[0011] The third embodiment of the present invention is a diaphragm valve according to the second embodiment, in which a chamfered portion of the second fixing portion is formed at the boundary between the inner peripheral surface of the second fixing portion and the piston-side end surface of the second fixing portion, and a chamfered portion on the inner peripheral side of the diaphragm retainer is formed at the boundary between the outer peripheral surface of the inner peripheral side of the diaphragm retainer and the end surface of the inner peripheral side of the diaphragm retainer. According to this embodiment, press-fitting can be facilitated.

[0012] The fourth embodiment of the present invention is a diaphragm valve according to any one of the first to third embodiments, in which the diaphragm retainer is made of a material having a higher mechanical strength than the diaphragm and the flow path side body. According to this embodiment, press-fitting becomes easy and the strength after press-fitting is high.

[0013] The fifth embodiment of the present invention is a diaphragm valve according to any one of the first to fourth embodiments, in which the diaphragm and the valve body are made of PTFE or PFA, and the diaphragm retainer is made of a fluororesin such as PVdF, a thermoplastic resin such as PPS or PP, or a composite material in which glass or carbon is mixed with a thermoplastic resin. According to this embodiment, by making the diaphragm and the valve body of PTFE or PFA, corrosion resistance is excellent and the flexibility of the diaphragm can also be accommodated.

[0014] In the sixth embodiment of the present invention, in the diaphragm valve according to any one of the first to fifth embodiments, the diaphragm retainer is sandwiched between the flow path side body and the drive side body, and a sliding surface for sliding the piston is formed at the center of the diaphragm retainer. According to this embodiment, since the diaphragm and the piston are positioned by the diaphragm retainer, displacement between the diaphragm and the piston is less likely to occur, and stable operation of the diaphragm can be ensured.

Example

[0015] Hereinafter, a diaphragm valve according to an embodiment of the present invention will be described. FIG. 1 is a cross-sectional view showing the valve-closed state of the diaphragm valve according to this embodiment.

[0016] The diaphragm valve 1 according to this embodiment has a flow path side body 10 and a drive side body 20. The flow path side body 10 internally forms an inflow passage 11 into which the fluid to be controlled flows, an outflow passage 12 from which the fluid to be controlled flows out, and a valve seat 13 located between the inflow passage 11 and the outflow passage 12. The drive side body 20 internally forms a cylindrical space 21 for the piston in which the piston 30 is disposed. Air flow passages 22 and 23 are formed in the drive side body 20. The air flow passage 22 communicates with a cylindrical space 21a for the piston between the diaphragm 60 and the piston enlarged portion 31, and the air flow passage 23 communicates with a cylindrical space 21b for the piston in which the piston biasing means 50 is disposed.

[0017] A valve body 40 is disposed at one end of the piston 30. The cylindrical space 21 for the piston has a piston biasing means 50 for biasing the piston 30. The piston biasing means 50 biases the piston 30 in the direction in which the valve body 40 abuts against the valve seat 13. The piston 30 has a piston enlarged portion 31. The piston biasing means 50 biases the piston 30 by pressing the piston enlarged portion 31. For example, a coil spring can be used for the piston biasing means 50. One end of the cylindrical space 21 for the piston opens at a position facing the valve seat 13. A diaphragm 60 is disposed in this opening, and the cylindrical space 21 for the piston and the valve seat 13 are partitioned by the diaphragm 60.

[0018] The diaphragm 60 is disposed on one end side of the piston 30. One end of the piston 30 is located at the center of the diaphragm 60, and a valve body 40 is disposed on the valve seat 13 side of the diaphragm 60. The diaphragm 60 deforms as the piston 30 moves.

[0019] The diaphragm 60 is attached to the flow path side body 10 by a diaphragm retainer 70. The diaphragm retainer 70 is sandwiched between the flow path side body 10 and the drive side body 20, and a sliding surface 71 for sliding the piston 30 is formed at the center of the diaphragm retainer 70. Therefore, since the diaphragm 60 and the piston 30 are positioned by the diaphragm retainer 70, displacement between the diaphragm 60 and the piston 30 is less likely to occur, and stable operation of the diaphragm 60 can be ensured. The diaphragm retainer 70 is formed with a communication hole 72 that communicates with the space surrounded by the diaphragm 60, the diaphragm retainer 70, and the piston 30.

[0020] FIG. 2 is a partial cross-sectional view of the main part of FIG. 1. The diaphragm 60 has a thick portion 61 connected to the piston 30, a film portion 62 formed on the outer periphery of the thick portion 61, and a fixing portion 63 formed on the outer periphery of the film portion 62. The diaphragm 60 is connected to the piston 30 at the central portion of the thick portion 61, and the film portion 62 mainly deforms. The fixing portion 63 has a first fixing portion 63A located on the film portion 62 side and a second fixing portion 63B located on the outer periphery of the first fixing portion 63A. The first fixing portion 63A is formed with a first fixing portion piston side end face 63Ap on the piston 30 side and a first fixing portion valve body side end face 63Ab on the valve body 40 side. The second fixing part 63B is formed with a second fixing part piston-side end face 63Bp on the piston 30 side, a second fixing part valve body-side end face 63Bb on the valve body 40 side, a second fixing part inner peripheral surface 63Bi on the inner peripheral side, and a second fixing part outer peripheral surface 63Bo on the outer peripheral side.

[0021] The flow path side body 10 has a body-side first end face 15 and a body-side ring-shaped convex part 16. On the body-side first end face 15, the first fixing part valve body-side end face 63Ab and the second fixing part valve body-side end face 63Bb are in contact. By the body-side ring-shaped convex part 16, a body-side convex part inner peripheral surface 16i is formed on the inner periphery, a body-side convex part outer peripheral surface 16o is formed on the outer periphery, and a body-side convex part end face 16s is formed at the end. On the flow path side body 10, a body-side ring-shaped groove is formed on the outer periphery of the body-side ring-shaped convex part 16. The second fixing part outer peripheral surface 63Bo abuts on the body-side convex part inner peripheral surface 16i.

[0022] The diaphragm retainer 70 has a diaphragm retainer inner peripheral side ring-shaped convex part 73 and a diaphragm retainer outer peripheral side ring-shaped convex part 74 located on the outer periphery of the diaphragm retainer inner peripheral side ring-shaped convex part 73. Between the diaphragm retainer inner peripheral side ring-shaped convex part 73 and the diaphragm retainer outer peripheral side ring-shaped convex part 74, a diaphragm retainer contact surface 75 is formed. On the outer periphery of the diaphragm retainer inner peripheral side ring-shaped convex part 73, a diaphragm retainer inner peripheral side outer peripheral surface 73o is formed, and at the tip of the diaphragm retainer inner peripheral side ring-shaped convex part 73, a diaphragm retainer inner peripheral side end face 73s is formed. On the inner periphery of the diaphragm retainer outer peripheral side ring-shaped convex part 74, a diaphragm retainer outer peripheral side inner peripheral surface 74i is formed, on the outer periphery of the diaphragm retainer outer peripheral side ring-shaped convex part 74, a diaphragm retainer outer peripheral side outer peripheral surface 74o is formed, and at the tip of the diaphragm retainer outer peripheral side ring-shaped convex part 74, a diaphragm retainer outer peripheral side end face 74s is formed. The diaphragm retainer inner peripheral side outer peripheral surface 73o and the diaphragm retainer outer peripheral side inner peripheral surface 74i are formed to face each other.

[0023] The inner peripheral side end face 73s of the diaphragm retainer is made to contact the piston side end face 63Ap of the first fixing portion, the outer peripheral surface 73o of the inner peripheral side of the diaphragm retainer is made to contact the inner peripheral surface 63Bi of the second fixing portion, the inner peripheral surface 74i of the outer peripheral side of the diaphragm retainer is made to contact the outer peripheral surface 16o of the body side convex portion, and the contact surface 75 of the diaphragm retainer is made to contact the piston side end face 63Bp of the second fixing portion and the end face 16s of the body side convex portion. Therefore, the diaphragm 60 can be firmly fixed to the flow path side body 10 by the diaphragm retainer 70. In this embodiment, by press-fitting the outer peripheral side ring-shaped convex portion 74 of the diaphragm retainer into the body side ring-shaped groove 17, the diaphragm 60 can be more firmly fixed to the flow path side body 10, but a wall thickness is not necessarily required on the outer periphery of the body side ring-shaped groove 17. By sandwiching the fixing portion 63 and the body side ring-shaped convex portion 16 with the diaphragm retainer 70, the diaphragm 60 can be firmly attached to the flow path side body 10. Since the outer wall thickness of the body side ring-shaped convex portion 16 does not affect the attachment of the diaphragm 60, it is not necessary to reduce or provide a wall thickness for the flow path side body 10 at the outer peripheral portion of the diaphragm 60, and miniaturization of the flow path side body 10 can be achieved.

[0024] Figure 3 is a detailed cross-sectional view of the main part of Figure 1. As shown in Figure 3, a chamfered portion 63c of the second fixing portion is formed at the boundary between the inner peripheral surface 63Bi of the second fixing portion and the piston side end face 63Bp of the second fixing portion, and a chamfered portion 73c of the inner peripheral side of the diaphragm retainer is formed at the boundary between the outer peripheral surface 73o of the inner peripheral side of the diaphragm retainer and the inner peripheral side end face 73s of the diaphragm retainer. The inner peripheral surface 16i of the body side convex portion and the outer peripheral surface 63Bo of the second fixing portion are brought into contact with each other without a gap over the entire surface. Also, the outer peripheral surface 16o of the body side convex portion and the inner peripheral surface 74i of the outer peripheral side of the diaphragm retainer are brought into contact with each other without a gap over the entire surface. Further, the inner peripheral surface 63Bi of the second fixing portion and the outer peripheral surface 73o of the inner peripheral side of the diaphragm retainer are brought into contact with each other without a gap over the entire surface except for the chamfered portion 63c of the second fixing portion and the chamfered portion 73c of the inner peripheral side of the diaphragm retainer.

[0025] Here, when the thickness of the body-side ring-shaped convex portion 16 is 16L, the thickness of the second fixing portion 63B is 63BL, and the gap dimension between the inner peripheral side outer peripheral surface 73o of the diaphragm retainer and the outer peripheral side inner peripheral surface 74i of the diaphragm retainer is 75L, it is set that 16L + 63BL > 75L. And, the inner peripheral side ring-shaped convex portion 73 of the diaphragm retainer and the outer peripheral side ring-shaped convex portion 74 of the diaphragm retainer are press-fitted into the body-side ring-shaped convex portion 16 and the second fixing portion 63B. In this way, by press-fitting the inner peripheral side ring-shaped convex portion 73 of the diaphragm retainer and the outer peripheral side ring-shaped convex portion 74 of the diaphragm retainer into the body-side ring-shaped convex portion 16 and the second fixing portion 63B, the diaphragm 60 can be more firmly attached to the flow path side body 10.

[0026] Also, since the second fixing portion chamfered portion 63c and the inner peripheral side chamfered portion 73c of the diaphragm retainer are formed, press-fitting can be facilitated. The diaphragm retainer 70 is made of a material having a higher mechanical strength than the diaphragm 60 and the flow path side body 10, so that press-fitting is easy and the strength after press-fitting is high.

[0027] The diaphragm 60 and the valve body 40 are preferably made of PTFE (polytetrafluoroethylene resin) or PFA (tetrafluoroethylene-perfluoroalkoxyethylene copolymer resin), and can also be made of a thermoplastic resin added with PTFE or PFA. By making the diaphragm 60 and the valve body 40 of PTFE or PFA, corrosion resistance is excellent and the flexibility of the diaphragm 60 can also be accommodated. The diaphragm retainer 70 is preferably made of a fluororesin such as PVdF (polyvinylidene fluoride), a thermoplastic resin such as PPS (polyphenylene sulfide) or PP (polypropylene), or a composite material in which glass or carbon is mixed with a thermoplastic resin. When using PTFE or PFA as the diaphragm retainer 70, the mechanical strength can be increased by inserting a metal guide into the outer peripheral side ring-shaped convex portion 74 of the diaphragm retainer. Note that the driving-side body 20 can be made of a fluororesin such as PTFE, PFA, or PVdF, or a thermoplastic resin such as PP, PVC, PPS, or PE. Note that the second fixed portion chamfered portion 63c and the diaphragm presser inner peripheral side chamfered portion 73c may not be provided.

[0028] FIG. 4 is a cross-sectional view of a main part of a diaphragm valve according to another embodiment of the present invention. In this embodiment, the configuration other than the use of a double film as the diaphragm 60 and the formation of the diaphragm presser 70 integrally with the driving-side body 20 is the same as that of the embodiments shown in FIGS. 1 to 3, and thus the same reference numerals are given and the description thereof is omitted. In this embodiment, the film portion 62 of the diaphragm 60 is composed of a piston-side film portion 62p and a valve body-side film portion 62b, and a ring-shaped diaphragm presser member 64 is disposed between the piston-side film portion 62p and the valve body-side film portion 62b. As described above, the diaphragm presser 70 may be formed by integral resin molding with the driving-side body 20, and the same applies to the embodiments shown in FIGS. 1 to 3. Note that when the film portion 62 is configured by the piston-side film portion 62p and the valve body-side film portion 62b as in this embodiment, the communication hole 72 is communicated with the film portion space between the piston-side film portion 62p and the valve body-side film portion 62b.

[0029] As described above, the diaphragm valve 1 according to this embodiment causes the diaphragm presser inner peripheral side end face 73s of the diaphragm presser inner peripheral side ring-shaped convex portion 73 to abut against the first fixed portion piston-side end face 63Ap, causes the diaphragm presser inner peripheral side outer peripheral surface 73o of the diaphragm presser inner peripheral side ring-shaped convex portion 73 to abut against the second fixed portion inner peripheral surface 63Bi, causes the diaphragm presser outer peripheral side inner peripheral surface 74i of the diaphragm presser outer peripheral side ring-shaped convex portion 74 to abut against the body-side convex portion outer peripheral surface 16o of the body-side ring-shaped convex portion 16, and causes the diaphragm presser contact surface 75 to abut against the second fixed portion piston-side end face 63Bp and the body-side convex portion end face 16s of the body-side ring-shaped convex portion 16. Thus, the diaphragm 60 can be firmly fixed to the flow path-side body 10 by the diaphragm presser 70.

Industrial Applicability

[0030] The present invention is suitable for a diaphragm valve particularly used in the cleaning and peeling processes of a silicon wafer process in the semiconductor manufacturing field.

Explanation of Signs

[0031] 1 Diaphragm valve 10 Flow path side body 11 Inflow flow path 12 Outflow flow path 13 Valve seat 14 Membrane part communication hole 15 Body side first end face 16 Body side ring-shaped convex part 16i Inner peripheral surface of body side convex part 16o Outer peripheral surface of body side convex part 16s End face of body side convex part 16L Thickness 17 Body side ring-shaped groove 20 Driving side body 21 Cylindrical space for piston 21a Cylindrical space for piston 21b Cylindrical space for piston 22, 23 Air flow path 30 Piston 31 Piston enlarged part 40 Valve body 50 Piston biasing means 60 Diaphragm 61 Thick part 62 Membrane part 62b Membrane part on valve body side 62p Membrane part on piston side 62s Membrane part space 63 Fixing part 63A First fixing part 63Ab End face of first fixing part on valve body side 63Ap End face of first fixing part on piston side 63B Second fixing part 63Bb End face of second fixing part on valve body side 63Bp End face of second fixing part on piston side 63Bi Inner peripheral surface of second fixing part Outer peripheral surface of the second fixing part Thickness of 63BL Chamfered part of the second fixing part Diaphragm pressing member Diaphragm presser Sliding surface Communication hole Inner peripheral side ring-shaped convex part of the diaphragm presser Inner peripheral side end surface of the diaphragm presser Inner peripheral side outer peripheral surface of the diaphragm presser Inner peripheral side chamfered part of the diaphragm presser Outer peripheral side ring-shaped convex part of the diaphragm presser Inner peripheral surface of the outer peripheral side of the diaphragm presser Outer peripheral surface of the outer peripheral side of the diaphragm presser Outer peripheral side end surface of the diaphragm presser Contact surface of the diaphragm presser Clearance dimension

Claims

1. A flow path side body forming an inflow flow path, an outflow flow path, and a valve seat, a drive side body having a piston disposed therein for moving a valve body relative to the valve seat, and a diaphragm disposed on one end side of the piston and having: the diaphragm having a thick portion connected to the piston, a film portion formed on the outer periphery of the thick portion, and a fixing portion formed on the outer periphery of the film portion and having: the fixing portion having a first fixing portion located on the film portion side, and a second fixing portion located on the outer periphery of the first fixing portion and having: on the first fixing portion, a first fixing portion piston-side end face is formed on the piston side and a first fixing portion valve body-side end face is formed on the valve body side, on the second fixing portion, a second fixing portion piston-side end face is formed on the piston side and a second fixing portion valve body-side end face is formed on the valve body side, and a second fixing portion inner peripheral surface is formed on the inner peripheral side and a second fixing portion outer peripheral surface is formed on the outer peripheral side, a diaphragm valve for attaching the fixing portion to the flow path side body by a diaphragm retainer, wherein the flow path side body has a body-side first end face for abutting the first fixing portion valve body-side end face and the second fixing portion valve body-side end face, and a body-side ring-shaped convex portion forming a body-side convex portion inner peripheral surface for abutting the second fixing portion outer peripheral surface and having: the diaphragm retainer having a diaphragm retainer inner peripheral side ring-shaped convex portion, and a diaphragm retainer outer peripheral side ring-shaped convex portion located on the outer periphery of the diaphragm retainer inner peripheral side ring-shaped convex portion and having: a diaphragm retainer abutting surface is formed between the diaphragm retainer inner peripheral side ring-shaped convex portion and the diaphragm retainer outer peripheral side ring-shaped convex portion, the diaphragm retainer inner peripheral side end face of the diaphragm retainer inner peripheral side ring-shaped convex portion is abutted against the first fixing portion piston-side end face, the diaphragm retainer inner peripheral side outer peripheral surface of the diaphragm retainer inner peripheral side ring-shaped convex portion is abutted against the second fixing portion inner peripheral surface, the diaphragm retainer outer peripheral side inner peripheral surface of the diaphragm retainer outer peripheral side ring-shaped convex portion is abutted against the body-side convex portion outer peripheral surface of the body-side ring-shaped convex portion, the diaphragm retainer abutting surface is a single-height same plane surrounded by the diaphragm retainer inner peripheral side ring-shaped convex portion and the diaphragm retainer outer peripheral side ring-shaped convex portion and extending from the diaphragm retainer outer peripheral side inner peripheral surface to the diaphragm retainer inner peripheral side outer peripheral surface, and the diaphragm retainer abutting surface is abutted against the second fixing portion piston-side end face and the body-side convex portion end face of the body-side ring-shaped convex portion A diaphragm valve characterized by the above.

2. The ring-shaped convex portion on the body side and the second fixing portion are press-fitted with the ring-shaped convex portion on the inner peripheral side of the diaphragm retainer and the ring-shaped convex portion on the outer peripheral side of the diaphragm retainer. The diaphragm valve according to claim 1, characterized in that.

3. A chamfered portion of the second fixing portion is formed at the boundary between the inner peripheral surface of the second fixing portion and the end surface on the piston side of the second fixing portion. A chamfered portion on the inner peripheral side of the diaphragm retainer is formed at the boundary between the outer peripheral surface on the inner peripheral side of the diaphragm retainer and the end surface on the inner peripheral side of the diaphragm retainer. The diaphragm valve according to claim 2, characterized in that.

4. The diaphragm retainer is made of a material having a higher mechanical strength than the diaphragm and the body on the flow path side. The diaphragm valve according to any one of claims 1 to 3, characterized in that.

5. The diaphragm and the valve body are made of PTFE or PFA. The diaphragm retainer is made of a fluororesin such as PVdF, a thermoplastic resin such as PPS or PP, or a composite material in which glass or carbon is mixed with a thermoplastic resin. The diaphragm valve according to any one of claims 1 to 4, characterized in that.

6. The diaphragm retainer is sandwiched between the body on the flow path side and the body on the drive side. A sliding surface for sliding the piston is formed at the center of the diaphragm retainer. The diaphragm valve according to any one of claims 1 to 5, characterized in that.

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