Diaphragm Valve

Abstract

To provide a diaphragm valve capable of preventing permeation of gas through a membrane part.SOLUTION: A diaphragm valve 1 of the present invention has a channel-side body 10 forming an inflow channel 11, an outflow channel 12 and a valve seat 13, a drive-side body 20 having in the inside thereof a piston 30 for moving a valve element 40 with respect to the valve seat 13, and a diaphragm 60 disposed on one end side of the piston 30. The diaphragm 60 has a thick wall part 61 connected to the piston 30, a membrane part 62 formed on the outer periphery of the thick wall part 61, and a fixed part 63 formed on the outer periphery of the membrane part 62. The membrane part 62 is formed from a piston-side membrane portion 62p and a valve element-side membrane portion 62b, and a ring-shaped diaphragm pressing member 64 is disposed between the piston-side membrane portion 62p and the valve element-side membrane portion 62b.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a diaphragm valve used in cleaning and peeling steps in silicon wafer processing, which often involves the use of highly corrosive chemicals, particularly strong acids and strong alkalis. [Background technology]

[0002] As disclosed in, for example, Patent Documents 1 to 6, a diaphragm valve has a diaphragm disposed on one end side of a piston, and the diaphragm has a membrane portion and a fixing portion formed on the outer periphery of the membrane portion. In such diaphragm valves, when highly corrosive fluids are used, the packing material may deteriorate due to gas components that permeate the membrane, or the gas components that permeate the membrane may enter the piston side and corrode the spring material, causing malfunction of the valve. In Patent Document 6, gas permeating the membrane is discharged by purging the gas on the piston side of the membrane. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-63777 A [Patent Document 2] JP 2020-26846 A [Patent Document 3] JP 2020-26847 A [Patent Document 4] JP 2016-65560 A [Patent Document 5] JP 2014-114888 A [Patent Document 6] JP 2004-19792 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the method described in Patent Document 6 consumes nitrogen gas, which poses economic and environmental problems.

[0005] SUMMARY OF THE PRESENT EMBODIMENTS An object of the present invention is to provide a diaphragm valve capable of preventing gas from passing through a membrane portion. [Means for solving the problem]

[0006] The diaphragm valve 1 of the present invention described in claim 1 comprises a flow passage side body 10 forming an inflow passage 11, an outflow passage 12, and a valve seat 13, a drive side body 20 accommodating a piston 30 therein for moving a valve body 40 relative to the valve seat 13, and a diaphragm 60 arranged on one end side of the piston 30, the diaphragm 60 having a thick portion 61 connected to the piston 30, a membrane portion 62 formed on the outer periphery of the thick portion 61, and a fixing portion 63 formed on the outer periphery of the membrane portion 62, the membrane portion 62 being composed of a piston side membrane portion 62p and a valve body side membrane portion 62b, and a ring-shaped diaphragm pressing member 64 being arranged between the piston side membrane portion 62p and the valve body side membrane portion 62b. By providing the diaphragm pressing member 64, the piston side membrane portion deformation area of ​​the piston side membrane portion 62p is made smaller than the valve body side membrane portion deformation area of ​​the valve body side membrane portion 62b. The present invention is characterized by the above. The present invention described in claim 2 is characterized in that, in the diaphragm valve 1 described in claim 1, the piston side membrane portion 62 and the piston side member surface 64p of the diaphragm pressing member 64 are always in contact even when the valve body 40 moves. The present invention described in claim 3 is characterized in that, in the diaphragm valve 1 described in claim 1 or claim 2, when the valve body 40 is in a fully open state, the diaphragm 60 is undeformed, and when the diaphragm 60 deforms, the valve body 40 moves toward the valve seat 13. The present invention according to claim 4 provides the diaphragm valve 1 according to any one of claims 1 to 3, wherein the piston side membrane portion 62p is provided with the diaphragm pressing member 64. The above The feature is that the deformation area of ​​the piston side membrane portion is made small. Claim 5 The invention as described herein comprises claims 1 to Claim 4In the diaphragm valve 1 described in any one of the above, the diaphragm holding member 64 is divided into at least two parts. Claim 6 The invention as described herein comprises claims 1 to Claim 5 In the diaphragm valve 1 described in any one of the above, a membrane portion communication hole 14 that communicates with the membrane portion space 62s between the piston side membrane portion 62p and the valve body side membrane portion 62b is formed in the flow path side body 10 or the drive side body 20. Claim 7 The invention as described herein comprises claims 1 to Claim 6 In the diaphragm valve 1 described in any one of claims 1 to 5, the thick portion 61 is formed at the piston side end of the valve body 40, and the diaphragm 60 and the valve body 40 are integrally molded from resin. Effect of the Invention

[0007] According to the diaphragm valve of the present invention, the membrane portion is made into a double membrane consisting of a piston side membrane portion and a valve body side membrane portion, thereby preventing gas from passing through the membrane portion, and deformation of the membrane portion can be regulated by a ring-shaped diaphragm pressing member. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a cross-sectional view showing a diaphragm valve in a closed state according to an embodiment of the present invention; [Diagram 2] FIG. 3 is a cross-sectional view showing the diaphragm valve in an open state. [Diagram 3] A diagram showing the configuration of a diaphragm according to this embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In the diaphragm valve according to the first embodiment of the present invention, the membrane portion is composed of a piston side membrane portion and a valve body side membrane portion, and a ring-shaped diaphragm pressing member is disposed between the piston side membrane portion and the valve body side membrane portion. The diaphragm pressing member makes the piston side membrane portion deformation area of ​​the piston side membrane portion smaller than the valve body side membrane portion deformation area of ​​the valve body side membrane portion. This is what we do. According to this embodiment, the membrane portion is made into a double membrane consisting of a piston side membrane portion and a valve body side membrane portion, thereby preventing gas from passing through the membrane portion, and deformation of the membrane portion can be regulated by a ring-shaped diaphragm pressing member. In addition, by making the deformation area of ​​the piston-side membrane portion smaller than the deformation area of ​​the valve body-side membrane portion, the pressure of the controlled fluid can be effectively used to move the piston.

[0010] A second embodiment of the present invention is a diaphragm valve according to the first embodiment, in which the piston side membrane portion and the piston side member surface of the diaphragm pressing member are always in contact with each other even when the valve body moves. According to this embodiment, the piston side member surface of the diaphragm pressing member is constantly in contact with the piston side membrane portion, so that deformation of the piston side membrane portion can be restricted.

[0011] A third embodiment of the present invention is a diaphragm valve according to the first or second embodiment, in which the diaphragm is undeformed when the valve body is fully open, and the valve body moves toward the valve seat as the diaphragm deforms. According to this embodiment, the piston side member surface of the diaphragm pressing member is always in contact with the piston side membrane portion, so that deformation of the piston side membrane portion can be restricted.

[0012] A fourth embodiment of the present invention is a diaphragm valve according to any one of the first to third embodiments, in which the piston side membrane portion is provided with a diaphragm pressing member to reduce the deformation area of ​​the piston side membrane portion. According to this embodiment, the deformation area of ​​the piston-side membrane part is reduced by the diaphragm pressing member, so that the gas pressure supplied between the piston and the diaphragm can be effectively used for the movement of the piston. Therefore, the piston can be moved without increasing the gas pressure supplied between the piston and the diaphragm.

[0013] The present invention Fifth The embodiment of the present invention is as follows: Fourth In the diaphragm valve according to any one of the embodiments, the diaphragm holding member is divided into at least two parts. According to this embodiment, the diaphragm pressing member can be easily attached to the diaphragm.

[0014] The present invention Sixth The embodiment of the present invention is as follows: Fifth In the diaphragm valve according to any one of the embodiments above, a membrane portion communication hole communicating with the membrane portion space between the piston side membrane portion and the valve body side membrane portion is formed in the flow path side body or the drive side body. According to this embodiment, it is possible to eliminate pressure fluctuations in the membrane space caused by deformation of the membrane, and to exhaust gas that has permeated the valve body side membrane portion.

[0015] The present invention Seventh The embodiment of the present invention is as follows: Sixth In the diaphragm valve according to any one of the embodiments above, the thick portion is formed at the piston side end of the valve body, and the diaphragm and the valve body are integrally molded from resin. According to this embodiment, the diaphragm and the valve body, which are prone to generating particles, are integrally molded from resin, making it possible to use a resin that is less likely to generate particles. EXAMPLES

[0016] A diaphragm valve according to one embodiment of the present invention will now be described. FIG. 1 is a cross-sectional view showing a diaphragm valve according to this embodiment in a valve closed state, and FIG. 2 is a cross-sectional view showing the same diaphragm valve in an open state.

[0017] 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 defines therein an inflow flow path 11 through which the controlled fluid flows in, an outflow flow path 12 through which the controlled fluid flows out, and a valve seat 13 located between the inflow flow path 11 and the outflow flow path 12. The driving side body 20 defines therein a cylindrical piston space 21 in which the piston 30 is disposed.

[0018] A valve body 40 is disposed at one end of the piston 30 . The piston cylindrical space 21 has a piston biasing means 50 for biasing the piston 30. The piston biasing means 50 biases the piston 30 in a direction in which the valve body 40 abuts against the valve seat 13. The piston 30 is formed with a piston enlarged portion 31. The piston biasing means 50 biases the piston 30 by pressing the piston enlarged portion 31. The piston biasing means 50 may be, for example, a coil spring. One end of the piston cylindrical space 21 opens at a position facing the valve seat 13 . A diaphragm 60 is disposed in this opening, and the piston cylindrical space 21 and the valve seat 13 are separated by the diaphragm 60 .

[0019] 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 the valve body 40 is disposed on the valve seat 13 side of the diaphragm 60. The diaphragm 60 deforms as the piston 30 moves. The diaphragm 60 has a thick portion 61 connected to the piston 30, a membrane portion 62 formed on the outer periphery of the thick portion 61, and a fixing portion 63 formed on the outer periphery of the membrane portion 62. The diaphragm 60 is connected to the piston 30 at the center of the thick portion 61, and the membrane portion 62 is mainly deformed. The membrane portion 62 is composed of a piston side membrane portion 62p and a valve body side membrane portion 62b, and a ring-shaped diaphragm pressing member 64 is disposed between the piston side membrane portion 62p and the valve body side membrane portion 62b.

[0020] The flow path side body 10 is formed with a membrane portion communication hole 14 that communicates with the membrane portion space 62s between the piston side membrane portion 62p and the valve body side membrane portion 62b. The membrane portion communication hole 14 may be provided in the drive side body 20. By providing the membrane portion communication hole 14, it is possible to eliminate pressure fluctuations in the membrane portion space 62s caused by deformation of the membrane portion 62, and to exhaust gas that has permeated the valve body side membrane portion 62b. Air flow passages 22 and 23 are formed in the driving side body 20. The air flow passage 22 communicates with a piston cylindrical space 21a between the diaphragm 60 and the piston expansion portion 31, and the air flow passage 23 communicates with a piston cylindrical space 21b in which the piston biasing means 50 is disposed.

[0021] FIG. 1 shows the valve body 40 in a closed state. The valve body 40 is in contact with the valve seat 13 due to the biasing force of the piston biasing means 50. In this state, the diaphragm 60 is displaced such that the thick portion 61 is closer to the valve seat 13 than the fixed portion 63, and the membrane portion 62 is in a deformed state.

[0022] FIG. 2 shows the valve body 40 in a fully open state. By supplying gas from the air flow passage 22 to the piston cylindrical space 21a, pressure is applied to the piston 30 in a direction opposite to the bias of the piston biasing means 50. Therefore, the piston 30 moves in a direction that separates the valve body 40 from the valve seat 13. When the valve body 40 separates from the valve seat 13, the controlled fluid flows in from the inflow passage 11, and the pressure of the controlled fluid is applied to the diaphragm 60. When the piston 30 moves, the diaphragm 60 moves to a position where the thick portion 61 is flush with the fixed portion 63. The movement of the thick portion 61 causes the membrane portion 62 to deform, increasing the gas pressure in the piston cylindrical space 21a between the diaphragm 60 and the piston 30. This gas pressure then causes the piston 30 to move further, and the valve body 40 becomes fully open as shown in FIG. 2. Note that, during the period from the state shown in FIG. 1 to the state shown in FIG. 2, the gas in the piston cylindrical space 21b is discharged from the air flow passage 23. 1 from the fully open state of the valve body 40 shown in Fig. 2, the gas in the piston cylindrical space 21a is discharged from the air flow passage 22. By discharging the gas from the piston cylindrical space 21a, the pressure in the piston cylindrical space 21a decreases, and the piston 30 moves in a direction approaching the valve seat 13 due to the biasing force of the piston biasing means 50. During the period from the state shown in Fig. 2 to the state shown in Fig. 1, gas is drawn into the piston cylindrical space 21b from the air flow passage 23.

[0023] FIG. 3 is a diagram showing the configuration of the diaphragm according to this embodiment. 3(a) and 3(b) show half of the diaphragm 60, with FIG. 3(a) showing the valve body 40 in an open state and FIG. 3(b) showing the valve body 40 in a closed state. As shown in Fig. 3(a), when the valve body 40 is in a fully open state, the diaphragm 60 is not deformed, and as shown in Fig. 3(b), the diaphragm 60 is deformed, causing the valve body 40 to move toward the valve seat 13. Here, the non-deformation of the diaphragm 60 refers to the shape of the diaphragm 60 in an unloaded state. In the state shown in Figure 3(a), the piston side member surface 64p of the diaphragm holding member 64 abuts against the piston side membrane portion 62p, and since the thick portion 61 can only move from this state in the direction of the valve body 40, the piston side member surface 64p of the diaphragm holding member 64 is always in abutment against the piston side membrane portion 62p, thereby restricting deformation of the piston side membrane portion 62p. In this way, the piston side membrane portion 62p and the piston side member surface 64p of the diaphragm holding member 64 are always in contact with each other even when the valve body 40 moves, thereby restricting deformation of the piston side membrane portion 62p.

[0024] The radial width of the piston side membrane portion 62p is P1, but the radial width within which the piston side membrane portion 62p can deform is P2 (P1>P2) due to the diaphragm holding member 64. Therefore, the piston side membrane portion deformation area of ​​the piston side membrane portion 62p is reduced by providing the diaphragm holding member 64. In this manner, by reducing the piston side membrane portion deformation area of ​​the piston side membrane portion 62p by the diaphragm holding member 64, the gas pressure supplied between the piston 30 and the diaphragm 60 can be effectively used for the movement of the piston 30. Therefore, the piston 30 can be moved without increasing the gas pressure supplied between the piston 30 and the diaphragm 60.

[0025] The radially deformable width of the piston-side film portion 62p is P2 by the diaphragm pressing member 64, and the radially deformable width of the valve body-side film portion 62b is B2. Since the inner diameter side positions of P2 and B2 are the same and P2 < B2, the piston-side film portion deformation region of the piston-side film portion 62p is smaller than the valve body-side film portion deformation region of the valve body-side film portion 62b. By making the piston-side film portion deformation region smaller than the valve body-side film portion deformation region in this way, the pressure of the fluid to be controlled can be effectively utilized for the movement of the piston 30.

[0026] Also, it is preferable to form the thick portion 61 at the piston-side end of the valve body 40 and integrally mold the diaphragm 60 and the valve body 40 with resin. By integrally molding the diaphragm 60 and the valve body 40 with resin, a resin in which particles are less likely to be generated can be used.

[0027] FIG. 3(c) is a perspective view of the diaphragm pressing member 64. As shown in FIG. 3(c), the diaphragm pressing member 64 is formed in a ring shape and is at least divided into two parts. By making it at least divided into two parts in this way, the diaphragm pressing member 64 can be easily attached to the diaphragm 60. And the diaphragm pressing member 64 is disposed between the fixing portions 63 and between the outer peripheral portions of the piston-side film portion 62p and the valve body-side film portion 62b.

[0028] As described above, in the diaphragm valve 1 according to this embodiment, the film portion 62 is composed of the piston-side film portion 62p and the valve body-side film portion 62b, and a ring-shaped diaphragm pressing member 64 is disposed between the piston-side film portion 62p and the valve body-side film portion 62b. By making the film portion 62 a double film with the piston-side film portion 62p and the valve body-side film portion 62b, it is possible to prevent gas from permeating through the film portion 62, and the deformation of the film portion 62 can be restricted by the ring-shaped diaphragm pressing member 64. In this embodiment, the valve body 40 is opened and closed by supplying or discharging gas from the air flow passage 22. However, for example, gas may be supplied or discharged from the air flow passage 23 together with the air flow passage 22 or instead of the air flow passage 22, or other methods may be used. [Industrial Applicability]

[0029] The present invention is particularly suitable for diaphragm valves used in the cleaning and peeling steps of silicon wafer processes in the field of semiconductor manufacturing. [Explanation of symbols]

[0030] 1 Diaphragm Valve 10 Flow passage side body 11 Inlet Channel 12 Outlet Channel 13 Valve seat 14 Membrane communication hole 20 Drive side body 21 Piston cylindrical space 21a Cylindrical space for piston 21b Cylindrical space for piston 22, 23 Air flow passage 30 Piston 31 Piston expansion section 32 Outer Circumferential Cone Section 40 Valve body 50 Piston biasing means 60 Diaphragm 61 Thick part 62 Membrane part 62b Valve body side membrane part 62p Piston side membrane 62s membrane space 63 Fixed part 64 Diaphragm retainer 64p Piston side material surface B2 Radial width P1 Radial width P2 Radial width

Claims

1. a flow passage side body that defines an inlet flow passage, an outlet flow passage, and a valve seat; a driving side body having a piston disposed therein for moving the valve body relative to the valve seat; A diaphragm disposed on one end side of the piston; having The diaphragm is A thick portion connected to the piston; A membrane portion formed on an outer periphery of the thick portion; A fixing portion formed on the outer periphery of the film portion; have 1. A diaphragm valve, comprising: The membrane portion is composed of a piston side membrane portion and a valve body side membrane portion, A ring-shaped diaphragm pressing member is disposed between the piston side membrane portion and the valve body side membrane portion, By providing the diaphragm pressing member, the piston side membrane portion deformation area of ​​the piston side membrane portion is made smaller than the valve body side membrane portion deformation area of ​​the valve body side membrane portion. A diaphragm valve characterized by:

2. The piston-side membrane portion and the piston-side member surface of the diaphragm pressing member are always in contact with each other even when the valve body moves.

2. The diaphragm valve of claim 1.

3. When the valve body is in a fully open state, the diaphragm is not deformed, The diaphragm is deformed, and the valve body moves toward the valve seat.

3. The diaphragm valve according to claim 1 or 2.

4. The piston-side membrane portion is provided with the diaphragm pressing member to reduce the deformation area of ​​the piston-side membrane portion.

4. The diaphragm valve according to claim 1, wherein the first and second electrodes are disposed in a first and second positions.

5. The diaphragm pressing member is divided into at least two parts.

5. The diaphragm valve according to claim 1, wherein the first and second electrodes are disposed in a first and second positions.

6. A membrane portion communication hole communicating with a membrane portion space between the piston side membrane portion and the valve body side membrane portion is formed in the flow passage side body or the drive side body.

6. The diaphragm valve according to claim 1, wherein the first and second electrodes are disposed in a first and second positions.

7. The thick portion is formed at a piston side end portion of the valve body, The diaphragm and the valve body are integrally molded from resin.

7. The diaphragm valve according to claim 1, wherein the first and second electrodes are disposed in a first and second positions.

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