JP2021038775A - Diaphragm valve - Google Patents

Abstract

To provide a diaphragm valve for preventing the entry of gas components permeating through a diaphragm part without lowering responsiveness during operation, while causing no performance difference or footprint difference.SOLUTION: The diaphragm valve includes a body part 11 having a valve chest 20 having an inflow part 12 on one side and an outflow part 13 formed on the other side via a valve seat 15, and an operation chamber 25 on the rear side of the valve chest, a valve mechanism part 30 having a diaphragm part 31 arranged on the valve chest side and a valve element 35 provided on the diaphragm part at its contact face 32 side with controlled fluid for opening/closing the valve seat, a reciprocation part 40 having a piston part 45 connected to the valve mechanism part via a rod part 41 for reciprocating in the operation chamber, a holding block part 50 arranged between the diaphragm part and the piston part for slidably holding the rod part, and a bellows film part 60 arranged on the operation chamber side, and fixed at one side to the holding block part and at the other side to the reciprocation part for extending and contracting in the reciprocating direction in association with the reciprocation of the reciprocation part.SELECTED DRAWING: Figure 1

Description

The present invention relates to a diaphragm valve.

In the field of semiconductor manufacturing, etc., in production lines, etc., pure water, ammonia water, hydrofluoric acid, hydrogen peroxide solution, hydrochloric acid, ozone water, hydrogen water, oxygen water, chemicals such as surfactants, gases such as hydrogen and oxygen. Various fluids such as, etc. are used according to the processing content, and a diaphragm valve is used for switching the flow of these fluids, controlling the flow rate, and the like.

In the diaphragm valve, for example, a valve body in which a diaphragm portion is integrally formed is arranged in a valve chamber in which a flow path through which a controlled fluid flows and a valve seat are formed, and a valve body is connected to the valve body to form a rear portion of the valve chamber. The valve body opens and closes the valve seat to control the flow of the controlled fluid by the advance / retreat of the advancing / retreating portion having the piston portion arranged in the operating chamber on the side. In this type of diaphragm valve, the diaphragm portion is in contact with the controlled fluid in the valve chamber, but when the controlled fluid is highly permeable, the gas component derived from the controlled fluid permeates the diaphragm portion to the working chamber. It may move to the side.

For example, when the advancing / retreating portion 140 is operated by air pressure as in the diaphragm valve 100 shown in FIGS. 5 and 6, in order to ensure the airtightness of the operating chamber 125, a packing member such as an O-ring is attached to the connecting portion of each member. 146 and 151 are arranged. In FIGS. 5 and 6, reference numeral 111 is a main body having a valve chamber 120 and an operating chamber 125, 112 is an inflow portion of a controlled fluid, 113 is an outflow portion of a controlled fluid, 115 is a valve seat of the valve chamber 120, and 126 is a valve seat of the valve chamber 120. The first airport where the working air that controls the operation of the advancing / retreating part 140 flows in and out, 127 is the second airport where the working air flows in and out, and 128 always urges the piston part 145 or the valve body 135 of the advancing / retreating part 140 in the forward direction. The urging member 130 is a valve mechanism portion having a diaphragm portion 131 and a valve body 135, 141 is a rod portion of an advancing / retreating portion 140 connecting the valve mechanism portion 130 and the piston portion 145, and 150 slides the rod portion 141. The holding block portion 155, which is capable of holding and fixing the outer edge portion of the diaphragm portion 131 to the main body portion 111, is a ventilation hole communicating with the rear side of the diaphragm portion 131.

However, when a highly corrosive controlled fluid such as hydrofluoric acid or ozone water is used, the packing members 146 and 151 are deteriorated by the gas component permeated through the diaphragm portion 131, and the gas component permeated through the diaphragm portion 131 is each deteriorated. There is a risk of malfunctions such as invading the operating chamber 125 side through a gap between members and corroding the operating mechanism.

Therefore, a diaphragm valve having a double diaphragm portion has been proposed (see, for example, Patent Document 1). For example, the diaphragm valve 200 shown in FIGS. 7 and 8 has a valve mechanism having a first diaphragm portion 231 arranged in a valve chamber 220 having a valve seat 215 and a valve body 235 integrally formed with the first diaphragm portion 231. A portion 230, an advance / retreat portion 240 having a piston portion 245 that is connected to the valve mechanism portion 230 and moves back and forth in the operating chamber 225 on the rear side of the valve chamber 220, and an advancing / retreating portion 240 that is arranged in the operating chamber 225 and fixed to the advancing / retreating portion 240 A second diaphragm portion 260 is provided.

In FIGS. 7 and 8, reference numeral 211 is a main body portion having a valve chamber 220 and an operating chamber 225, 212 is an inflow portion of the controlled fluid, 213 is an outflow portion of the controlled fluid, and 226 is an operation for controlling the operation of the advancing / retreating portion 240. The first airport where air flows in and out, 227 is the second airport where working air flows in and out, 228 is an urging member that constantly urges the piston portion 245 to the valve body 235 in the forward direction, and 241 is the valve mechanism portion 230 and the piston. The rod portion of the advancing / retreating portion 240 that connects the portion 245, 250 is a holding block portion that holds the rod portion 241 slidably and fixes the outer edge portion of the first diaphragm portion 231 to the main body portion 211, and 255 is the first diaphragm. It is a ventilation hole that communicates with the rear side of the portion 231.

In the diaphragm valve 200, since the airtightness of the operating chamber 225 is ensured by the second diaphragm portion, the conventional packing member becomes unnecessary when operating by air pressure, and the second diaphragm portion 260 is the first diaphragm portion 231. It is possible to prevent the gas component permeating through the air from entering the operating chamber 225 side and avoid the influence of the gas component.

However, in the diaphragm valve 200, when the advancing / retreating portion 240 is activated (in the example of FIG. 7, when the diaphragm portion 240 is retracted), the pressure of the operating air is repelled by the piston portion 245 and the second diaphragm portion 260, and the second diaphragm portion 260 is moved. Since the second diaphragm portion 260 is deformed so as to be pulled in conjunction with the advance / retreat movement of the advance / retreat portion 240, stress is generated in the second diaphragm portion 260, and a load in the opposite direction to the advance / retreat direction of the advance / retreat portion 240 acts. The repulsion of the pressure of the working air and the action of the stress of the second diaphragm portion 260 hinder the operation of the advancing / retreating portion 240. Therefore, in order to obtain the required operating load of the advancing / retreating portion 240, the piston portion 245 secures a pressure receiving area of the piston portion 245 capable of operating the advancing / retreating portion 240 against the urging force of the urging member 228. The pressure receiving area of the second diaphragm portion 260 must be sufficiently large with respect to the pressure receiving area of the second diaphragm portion 260. Therefore, there arises a problem that the diaphragm valve 200 becomes large and the footprint is affected.

Further, in the above diaphragm valve, if the amount of movement of the advancing / retreating portion is larger than the size of the second diaphragm portion, the second diaphragm portion may be destroyed, and the size of the second diaphragm portion is the operation of the advancing / retreating portion. Affects quantity. Therefore, there are performance differences and footprint differences due to the enlargement of the diaphragm valve, such as the limitation of the amount of movement of the advancing / retreating part and the need to increase the outer shape of the second diaphragm part according to the type of fluid to be controlled and the processing content. There was a problem that occurred.

Such a problem also occurs in a diaphragm valve whose operation is controlled by a method other than pneumatic pressure. Therefore, there is a demand for a diaphragm valve that avoids corrosion due to the gas component that has passed through the diaphragm portion and does not cause problems such as performance difference and footprint difference.

Special Table 2007-534893

The present invention has been made in view of the above points, and provides a diaphragm valve that prevents the intrusion of gas components that have passed through the diaphragm portion and does not cause a difference in performance or footprint.

That is, the invention of claim 1 is a valve chamber having an inflow portion of the controlled fluid on one side and an outflow portion of the controlled fluid on the other side via a valve seat, and a rear side of the valve chamber. The valve seat is provided on the contact surface side of the operating chamber, the main body having the valve chamber and the operating chamber, the diaphragm portion arranged on the valve chamber side, and the controlled fluid of the diaphragm portion. A valve body that opens and closes, a valve mechanism portion having the diaphragm portion and the valve body, an advancing / retreating portion having a piston portion connected via the valve mechanism portion and the rod portion and advancing / retreating in the operating chamber, and the diaphragm. A holding block portion that is arranged between the portion and the piston portion to slidably hold the rod portion, and a holding block portion that is arranged on the working chamber side and one side is fixed to the holding block portion and the other side is the advancing / retreating portion. The present invention relates to a diaphragm valve including a bellows membrane portion that is fixed to and expands and contracts in the advancing / retreating direction in conjunction with the advancing / retreating movement of the advancing / retreating portion.

The invention of claim 2 relates to the diaphragm valve according to claim 1, wherein the bellows membrane portion is made of a fluororesin.

The invention of claim 3 relates to the diaphragm valve according to claim 1 or 2, wherein the bellows membrane portion does not fully extend when the piston portion retracts.

According to the diaphragm valve according to the invention of claim 1, a valve chamber having an inflow portion of the controlled fluid on one side and an outflow portion of the controlled fluid on the other side via a valve seat, and the valve chamber. The operation chamber on the rear side, the main body having the valve chamber and the operation chamber, the diaphragm portion arranged on the valve chamber side, and the diaphragm portion provided on the contact surface side with the controlled fluid of the diaphragm portion. A valve body that opens and closes the valve seat, a valve mechanism portion having the diaphragm portion and the valve body, and an advancing / retreating portion having a piston portion connected via the valve mechanism portion and the rod portion and advancing / retreating in the operating chamber. A holding block portion arranged between the diaphragm portion and the piston portion to slidably hold the rod portion, and a holding block portion arranged on the working chamber side and one side fixed to the holding block portion and the other side Since it is provided with a bellows membrane portion that is fixed to the advancing / retreating portion and expands / contracts in the advancing / retreating direction in conjunction with the advancing / retreating movement of the advancing / retreating portion, it is possible to prevent the intrusion of gas components that have passed through the diaphragm portion, and there are a wide variety of types. Performance differences and footprint differences are less likely to occur with respect to the controlled fluid.

According to the diaphragm valve according to the invention of claim 2, in the invention of claim 1, since the bellows membrane portion is made of fluororesin, corrosion due to the gas component permeating the diaphragm portion can be appropriately avoided.

According to the diaphragm valve according to the invention of claim 3, in the invention of claim 1 or 2, the bellows membrane portion does not fully extend when the piston portion retracts, so that the size of the bellows membrane portion is the amount of operation of the advancing / retreating portion. The load acting on the bellows membrane is appropriately distributed regardless of the expansion and contraction state of the bellows membrane.

It is an overall sectional view at the time of opening of the diaphragm valve which concerns on one Embodiment of this invention. It is the whole cross-sectional view at the time of closing of the diaphragm valve of FIG. It is an enlarged cross-sectional view around the bellows membrane part at the time of advancing of the advancing part. It is an enlarged cross-sectional view around the bellows membrane part at the time of the retreat of the advancing part. It is the whole cross-sectional view at the time of opening of the conventional diaphragm valve. FIG. 5 is an overall cross-sectional view of the diaphragm valve of FIG. 5 when closed. It is the whole cross-sectional view at the time of opening of the conventional diaphragm valve provided with a double diaphragm part. FIG. 7 is an overall cross-sectional view of the diaphragm valve of FIG. 7 when closed.

The diaphragm valve 10 according to the embodiment of the present invention shown in FIGS. 1 and 2 is a valve device mainly arranged in a fluid pipeline of a semiconductor manufacturing factory, a semiconductor manufacturing device, or the like, and is composed of pure water, aqueous ammonia, and the like. It switches the flow of controlled fluids such as hydrofluoric acid, hydrogen peroxide solution, hydrochloric acid, ozone water, hydrogen water, oxygen water, chemicals such as surfactants, and gases such as hydrogen and oxygen, and controls the flow rate. The diaphragm valve 10 is used as an appropriate valve device such as a flow rate control valve, an on-off valve, a mixing valve, etc., depending on the application and the like.

The diaphragm valve 10 of the present invention includes a main body portion 11, a valve mechanism portion 30, an advancing / retreating portion 40, a holding block portion 50, and a bellows membrane portion 60. In this diaphragm valve 10, in order to cope with the use of a highly corrosive controlled fluid, the main body portion 11, the valve mechanism portion 30, the advancing / retreating portion 40, the holding block portion 50, and the bellows membrane portion 60 have corrosion resistance and chemical resistance. Consists of high-quality materials. For example, it is a fluororesin such as PTFE, PFA, PVDF and the like. The fluororesin can be easily processed into a desired shape by cutting or the like.

The main body 11 has a valve chamber 20 having an inflow portion 12 for a controlled fluid on one side and an outflow portion 13 for a controlled fluid formed on the other side via a valve seat 15, and a rear side of the valve chamber 20. Has an operating chamber 25 and the like.

The valve mechanism portion 30 has a diaphragm portion 31 and a valve body 35. The diaphragm portion 31 is made of a thin movable membrane arranged on the valve chamber 20 side, and prevents the controlled fluid flowing in the valve chamber 20 from entering the operating chamber 25 side. The valve body 35 is a member provided on the side of the diaphragm portion 31 on the contact surface 32 side with the controlled fluid to open and close the valve seat 15.

The advancing / retreating portion 40 has a piston portion 45 that is connected to the valve mechanism portion 30 via a rod portion 41 and advances / retreats in the operating chamber 25. The advancing / retreating portion 40 operates the valve body 35 of the valve mechanism portion 30 in the closing direction of the valve seat 15 via the rod portion 41 by advancing the piston portion 45, and via the rod portion 41 by retreating the piston portion 45. The valve body 35 of the valve mechanism portion 30 is operated in the opening direction of the valve seat 15.

The advancing / retreating portion 40 is operated by an appropriate operating means such as air pressure, electromagnetic force, a motor, and a manually operated spring mechanism. In the illustrated example, the operation of the advancing / retreating portion 40 is controlled by air pressure. In the figure, reference numeral 26 is a first airport through which working air that controls the operation of the advancing / retreating portion 40 flows in and out, and 27 is a second airport through which working air flows in and out.

Further, in the advancing / retreating portion 40 shown in the drawing, an urging member 28 made of a coil spring is arranged at the rear portion of the piston portion 45, and the piston portion 45 is constantly urged in the forward direction by the urging member 28. Therefore, the valve body 35 is held in the closed state. Although not shown, it is also possible to constantly urge the piston portion in the backward direction by an appropriate urging member such as an air pressure, an electromagnetic force, a motor, or a spring member to hold the valve body in an open state.

The holding block portion 50 is a member arranged between the diaphragm portion 31 and the piston portion 45 to slidably hold the rod portion 41. The holding block portion 50 is fixed to the main body portion 11. Further, the holding block portion 50 of the illustrated example also serves as a diaphragm fixing portion for fixing the outer edge portion of the diaphragm portion 31 to the main body portion 11. In the figure, reference numeral 55 is a ventilation hole communicating with the rear side of the diaphragm portion 31.

The bellows membrane portion 60 is arranged on the operating chamber 25 side, one side is fixed to the holding block portion 50 and the other side is fixed to the advancing / retreating portion 40, and the bellows membrane portion 60 expands / contracts in the advancing / retreating direction in conjunction with the advancing / retreating movement of the advancing / retreating portion 40. It is a thin movable membrane. As shown in FIGS. 3 and 4, the bellows membrane portion 60 is formed in a bellows shape in which the thin-walled portion 61 is a series of a plurality of peak portions 62 and valley portions 63. In the bellows membrane portion 60, the bellows-shaped thin-walled portion 61 has a plurality of peaks 62 and valleys 63, so that the load acting on the thin-walled portion 61 is dispersed.

Further, in the bellows membrane portion 60, the bellows-shaped thin-walled portion 61 is compression-deformed when the piston portion 45 of the advancing / retreating portion 40 is advanced, and the bellows-shaped thin-walled portion 61 is elongated and deformed when the piston portion 45 is retracted. In particular, when the piston portion 45 is retracted, the bellows membrane portion 60 does not fully extend even if it is expanded and deformed. That is, the bellows shape of the thin-walled portion 61 is always maintained even when the bellows membrane portion 60 expands and contracts in conjunction with the advance / retreat of the advance / retreat portion 40. Therefore, the load acting on the thin-walled portion 61 is appropriately dispersed regardless of the expansion / contraction state of the bellows membrane portion 60.

As described above, the bellows membrane portion 60 is made of a fluororesin such as PTFE or PFA having high corrosion resistance and chemical resistance, so that corrosion due to the gas component that has passed through the diaphragm portion 31 can be appropriately avoided. The thickness of the bellows membrane portion 60 is preferably 0.2 to 1.0 mm from the viewpoint of preventing the permeation of the gas component that has passed through the diaphragm portion 31 and the elasticity due to the bellows shape. If the bellows membrane portion 60 is too thin, the gas component may permeate, and if it is too thick, the elasticity may decrease.

In the diaphragm valve 10 of the present invention, the bellows membrane portion 60 is arranged between the holding block portion 50 and the advancing / retreating portion 40 to ensure the airtightness of the operating chamber 25, so that ozone water and the like are highly permeable. Even when the gas component of the controlled fluid permeates through the diaphragm portion 31 when the controlled fluid is used, the bellows membrane portion 60 can prevent the gas component from entering the operating chamber 25 side.

Further, by arranging the holding block portion 50 between the diaphragm portion 31 and the piston portion 45, the diaphragm portion 31 on the valve chamber 20 side and the bellows membrane portion 60 on the operating chamber 25 side are separated from each other, and the valve chamber is separated. A gap 70 at a predetermined interval is formed between the 20 and the operating chamber 25. Therefore, when an unstable gas component such as ozone permeates the diaphragm portion 31, the gas component is almost decomposed in the gap portion 70 and the migration to the working chamber 25 side is suppressed, and the bellows membrane portion 60 becomes. It is possible to prevent the invasion of gas components more effectively.

Further, the bellows membrane portion 60 expands and contracts in the advancing / retreating direction in conjunction with the advance / retreat of the advancing / retreating portion 40 to reduce the stress generated at the time of advancing / retreating, and the thin-walled portion 61 has a bellows shape, so that the bellows membrane portion 60 The weight acting on the snake is dispersed and reduced. As a result, the influence of the load acting on the bellows membrane portion 60 on the operation of the advancing / retreating portion 40 is suppressed, so that the pressure receiving area of the piston portion 45 is as shown in the conventional diaphragm valve (200) as shown in FIGS. There is no need to increase. In addition, the bellows membrane portion 60 is arranged along the advancing / retreating direction of the advancing / retreating portion 40, and expands / contracts in conjunction with the advancing / retreating movement of the advancing / retreating portion 40. The size of the bellows membrane portion 60 does not affect the amount of operation of the advancing / retreating portion 40, and it is unlikely to be destroyed when deformed due to the operation. Therefore, it is possible to avoid an increase in the size of the diaphragm valve 10 regardless of the type of the controlled fluid, the processing content, and the like, and it is difficult for performance differences and footprint differences to occur even for a wide variety of controlled fluids. For example, it can have the same footprint as the conventional diaphragm valve (100) which is not enlarged as shown in FIGS. 5 and 6.

As described above, the diaphragm valve of the present invention can prevent the intrusion of gas components that have passed through the diaphragm portion, and performance differences and footprint differences are unlikely to occur with respect to a wide variety of controlled fluids. Therefore, it is extremely promising as an alternative to conventional diaphragm valves.

10 Diaphragm valve 11 Main body 12 Inflow part 13 Outflow part 15 Valve seat 20 Valve room 25 Operating room 26 1st airport 27 2nd airport 28 Biasing member 30 Valve mechanism part 31 Diaphragm part 32 Contact surface 35 Valve body 40 Advance / retreat part 41 Rod part 45 Piston part 50 Holding block part 55 Vent hole 60 Bellows membrane part 61 Bellows-shaped thin wall part 62 Mountain part 63 Valley part 70 Gap part

Claims (3)

A valve chamber having an inflow portion for the controlled fluid on one side and an outflow portion for the controlled fluid on the other side via a valve seat.
The working chamber on the rear side of the valve chamber and
A main body having the valve chamber and the operating chamber,
The diaphragm portion arranged on the valve chamber side and
A valve body provided on the contact surface side of the diaphragm portion with the controlled fluid to open and close the valve seat, and a valve body.
A valve mechanism portion having the diaphragm portion and the valve body,
An advancing / retreating portion having a piston portion that is connected to the valve mechanism portion via a rod portion and advances / retreats in the operating chamber.
A holding block portion arranged between the diaphragm portion and the piston portion to slidably hold the rod portion, and a holding block portion.
It is provided with a bellows membrane portion which is arranged on the working chamber side, one side is fixed to the holding block portion, and the other side is fixed to the advancing / retreating portion and expands / contracts in the advancing / retreating direction in conjunction with the advancing / retreating of the advancing / retreating portion. Diaphragm valve featuring. The diaphragm valve according to claim 1, wherein the bellows membrane portion is made of a fluororesin. The diaphragm valve according to claim 1 or 2, wherein the bellows membrane portion does not fully extend when the piston portion retracts.

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