JP7162334B2 - diaphragm control valve - Google Patents

Description

The present invention relates to a diaphragm-type control valve suitable for use in fluidizing high-purity chemicals and ultrapure water in semiconductor manufacturing equipment.

Conventionally, this type of control valve includes a bottom housing member, an upper housing member, and a middle housing member assembled between the bottom housing member and the middle housing member. a housing having one housing chamber formed between them and the other housing chamber between the middle housing member and the bottom housing member, and a first pressure regulating chamber on the upper housing member side A first diaphragm that partitions the inside of the one-side storage chamber so as to form a first liquid chamber on the middle housing side, and a second pressure regulating chamber on the bottom housing member side and the middle side A second diaphragm that partitions the inside of the other storage chamber so as to form a second liquid chamber on the housing side; a shaft-like connecting member extending from the central portion of the first diaphragm; and a shaft-like valve body member extending from the central portion of the second diaphragm into the central communication passage and connected to the shaft-like connecting member. .

Therefore, in the control valve configured as described above, when the liquid flowing from the inflow side flows into the first liquid chamber and the second liquid chamber, the hydraulic pressure of the liquid flowing into the first liquid chamber is increased to the first level. A setting in which the pressure of the liquid flowing into the second liquid chamber acts against the set pressure acting on the first diaphragm from the first pressure regulating chamber side and acts on the second diaphragm from the second pressure regulating chamber side. Acts against pressure.

Along with this, the structural body consisting of the first diaphragm, the second diaphragm, and the shaft-like connecting member and the shaft-like valve body member that are coupled or separably connected to each other are arranged to act in opposition to each other through the first diaphragm. The central connection displaces according to the set pressure in the pressure chamber and the liquid pressure in the first liquid chamber, and the set pressure in the second pressure regulating chamber and the liquid pressure in the second liquid chamber, which act opposite to each other via the second diaphragm. An annular valve seat provided at the first liquid chamber side opening end of the passage and a valve body provided on the shaft-like valve member so as to face the annular valve seat from the inside of the second liquid chamber. Control the interval to a constant interval.

This means that the control valve allows the liquid flowing in from the inflow side to flow under both set pressures and the valve body portion of the shaft-like valve body member and the valve body portion of the shaft-like valve body member along with the displacement of the structure according to the flow rate of the liquid. This means that the fluid is controlled to flow out to the outflow side at a constant flow rate corresponding to a constant interval between the central communicating passage and the annular valve seat portion.

When a control valve having such a configuration is used in a semiconductor manufacturing apparatus, in a cleaning process or a peeling process in the semiconductor manufacturing apparatus, a highly corrosive chemical such as a strong acid or strong alkali is used as the above liquid. As a material for forming the diaphragm in the control valve, it is desirable to use fluororesin, which is excellent in chemical resistance such as acid resistance and alkali resistance.

In addition, in semiconductor manufacturing equipment, elution of metal components and organic components from control valves is not permitted, so it is desirable to employ a fluororesin having a low elution property as the material for forming the diaphragm.

In view of the structure of the control valve as described above, it is desirable to employ a fluororesin that is excellent in flexibility and capable of maintaining a long service life.

For the reasons described above, it is required to employ a fluororesin, which has chemical resistance, low elution, excellent flexibility, and can maintain a long life, as a material for forming the diaphragm.

Japanese Patent No. 5286330

By the way, in the control valve having the configuration described above, since contamination of the liquid by particles from the control valve is not allowed in the semiconductor manufacturing equipment, the liquid flowing through the flow channel system in the control valve is It is necessary to isolate it from one chamber, and for that purpose, it is required that the diaphragm is integrally constructed with an outer peripheral portion, a curved displacement portion and a central portion.

Here, when PTFE is adopted as the material for forming the diaphragm, since PTFE has a low melt flow rate, it is impossible to form a diaphragm of good quality by injection molding or extrusion molding. Therefore, the diaphragm is formed by cutting a compression-molded round bar of PTFE.

Although the PTFE diaphragm formed by cutting in this way has a long service life, in a control valve using such a diaphragm, a curved displacement portion formed by cutting extends or extends on the surface as the diaphragm is operated. Due to the compression, a small amount of dust is generated from the curved displacement portion. However, such dust generation is within an allowable range, for example, when the wiring pitch of a silicon wafer manufactured by a semiconductor manufacturing apparatus is larger than 10 (nm).

When PFA is used instead of PTFE as the material for forming the diaphragm, the diaphragm is formed by cutting an injection-molded round bar, a compression-molded round bar, or an extrusion-molded round bar.

The life of the PFA diaphragm formed by cutting in this way is short. In addition, in the control valve using the PFA diaphragm formed by cutting in this way, the PTFE diaphragm formed by cutting is displaced on the surface of the curved displacement portion formed by cutting along with its operation. As with the curved displacement portion, since the curved displacement portion is stretched or compressed, a small amount of dust is generated from the curved displacement portion.

Here, when PFA is adopted as the material for forming the diaphragm, and the PFA is used to form a thick curved portion by injection molding and by cutting, the thickness of the diaphragm is formed by injection molding or compression molding. When molded into a meat shape, crystallization does not occur uniformly at the curved displacement portion, and the interface becomes a starting point of fracture and life is shortened. .

On the other hand, in recent years, there has been a demand for further miniaturization in the production of semiconductor elements, such as silicon wafers, by semiconductor production apparatuses. For example, there is a demand to reduce the wiring pitch on a silicon wafer to 10 (nm) or less. Therefore, even particles with a size of several nanometers are not allowed to be generated from the control valve.

However, as described above, in a control valve using a diaphragm formed by cutting, the surface of the curved displacement portion formed by cutting causes extension and compression during its operation. Dust is produced, albeit minutely.

In such a case, it is not possible to cope with the situation where even particles with a size of several nanometers are not permitted to be emitted from the control valve described above. requested.

On the other hand, since the PFA film is thin, the crystallization can be made uniform. If adopted, it will lead to the improvement of the diaphragm described above.

By the way, in the above control valve, the first diaphragm is connected with the shaft-like connecting member at its central portion. However, if a film-like and very thin diaphragm as described above is adopted as the first diaphragm of the control valve, a connecting portion necessary for connecting with the shaft-like connecting member is formed at the central portion of the diaphragm. you can't. This means that it is extremely difficult to connect the central portion of the film-like first diaphragm to the shaft-like connecting member without the connecting portion.

In order to solve this problem, it is conceivable to use a configuration of a diaphragm valve that applies laser welding according to the resin diaphragm sealing method described in Patent Document 1 above.

In the diaphragm valve disclosed in Patent Document 1, the flange portion of the diaphragm is laser-welded to the flange portion of the lower housing so as to seal the valve body chamber for the purpose of sealing. Focusing on such a fact, the inventors came up with the idea that it would be possible to use laser welding to connect the central portion of the film-like diaphragm made of PFA and the shaft-like connecting member.

Therefore, in order to cope with the above problems, the present invention forms a film-like PFA that can ensure flexibility and long life, and a diaphragm that can suppress dust generation of about several nanometers to a minimum. In addition to selecting the material, an appropriate fluororesin shaft-shaped connecting member is used in consideration of the ease of connection with the central part of the diaphragm, and even if the diaphragm is thin like a film, the valve body and the diaphragm are connected. An object of the present invention is to provide a control valve using a diaphragm member configured as a diaphragm structure to which laser welding is applied for connection with a central portion.

In order to solve the above problems, the diaphragm type control valve according to the present invention, according to the description of claim 1,
The flow rate of the liquid such as high-purity chemical or ultrapure water flowing into the inflow side and flowing out to the outflow side is controlled according to the fluctuation of the liquid pressure.

In the control valve,
Cylindrical peripheral walls (140, 150), opposing walls (110, 180) facing each other so as to block the tubular peripheral walls from their axial end openings, and the inside of the tubular peripheral walls facing each other Partitioned so as to form a first storage chamber (S) with one of the walls (180) and a second storage chamber (R) with the other wall (110) a housing (100) having a partition wall (130) that
a first diaphragm member (200) housed in a first housing chamber and having a PFA film-like first diaphragm (200a) and a fluororesin shaft-like connecting member (200c);
A second diaphragm member (300) that is housed in the second housing chamber and has a film-like second diaphragm (300a) made of PFA and a shaft-shaped valve body member (300c) made of fluororesin,
In the first diaphragm member,
The first diaphragm is supported at its outer peripheral portion (210) in an axially intermediate portion of the peripheral wall portion of the cylindrical peripheral wall on the side of the first storage chamber, and moves the inside of the first storage chamber to the above one side. A first pressure regulating chamber (Sa) is formed on the opposing wall side of and a first liquid chamber (Sb) is formed on the partition wall side ,
Of the two surfaces of the first diaphragm, the surface on the first pressure regulating chamber side is one side surface, and the surface on the first liquid chamber side is the other side surface . It is joined to the central portion of the first diaphragm on the side surface side by laser welding and extends from the central portion of the first diaphragm into the first liquid chamber,
In the second diaphragm member,
The second diaphragm is supported at its outer peripheral portion (310) in an axially intermediate portion of the peripheral wall portion on the side of the second storage chamber of the cylindrical peripheral wall, and the inside of the second storage chamber is defined as the other side. A second pressure regulating chamber (Ra) is formed on the opposing wall side of the partition wall, and a second liquid chamber (Rb) is formed on the partition wall side ,
Of the two surfaces of the second diaphragm, the surface on the second liquid chamber side is one side surface, and the surface on the second pressure regulating chamber side is the other side surface . A base (360) joined to the central portion of the second diaphragm by laser welding, and a shaft-like connecting member passing through a central communicating passage (133) formed from the base to the central portion of the second liquid chamber and the partition wall. a rod (370) coupled to the extending end of the
The partition wall has an annular valve seat that faces the valve body portion (370b) of the shaft-shaped valve body member at the opening portion on the second liquid chamber side of the central communication passage and forms a valve portion together with the valve body portion. having a portion (133a),
The cylindrical peripheral wall includes inflow passages (160, 131) for allowing the liquid to flow into the second liquid chamber from the inflow side, and the liquid in the second liquid chamber through the annular valve seat portion, the central communication passage and the first liquid chamber. provided with an outflow path (132, 170) for flowing out to the outflow side through
In a state in which the first diaphragm receives the set pressure generated in the first pressure regulating chamber and the second diaphragm receives the set pressure generated in the second pressure regulating chamber, the first diaphragm and the second diaphragm receive the liquid on the inflow side. By controlling the opening degree between the valve body portion and the annular valve seat portion to a constant opening degree according to pressure fluctuations through the shaft-shaped connecting member and the shaft-shaped valve body member that are coupled to each other. , the liquid on the inflow side passes through the inflow passage, the second liquid chamber, the annular valve seat portion, the central communication passage, the first liquid chamber and the outflow passage at a constant flow rate according to the constant opening. It is characterized by flowing out to the outflow side.

According to this, in the control valve, an integrated structure composed of the first diaphragm, the shaft-like connecting member and the shaft-like valve body member, and the second diaphragm, which are connected to each other, flows under both set pressures. In response to fluctuations in the hydraulic pressure of the liquid flowing in from the side, the opening of the valve body with respect to the annular valve seat is displaced to a constant opening, and control is performed to keep the flow rate of the liquid constant. .

Here, the first diaphragm member is composed of a first diaphragm made of PFA and a fluororesin shaft-like connecting member that is coaxially joined to the central portion of the first diaphragm by laser welding and extends from the central portion. It consists of both.

Therefore, even if the first diaphragm is thin and difficult to handle, since the central portion of the first diaphragm is already laser-welded to the base portion of the shaft-like connecting member as described above, the shaft-like connecting member plays a reinforcing role for the first diaphragm. and the first diaphragm can be easily supported in the axially intermediate portion of the cylindrical peripheral wall.

In addition, the second diaphragm member is composed of a second diaphragm made of PFA and a fluororesin shaft-shaped valve body member that is coaxially joined to the central portion of the second diaphragm by laser welding and extends from the central portion. It consists of both.

According to this, the central portion of the second diaphragm and the shaft-like valve member are connected by laser welding, so that the shaft-like valve member and the central portion of the second diaphragm can be joined and connected satisfactorily.

Also, the first diaphragm is formed as a film-shaped diaphragm with PFA together with the second diaphragm. Therefore, even if the first diaphragm and the second diaphragm are film-like, they can be formed as diaphragms that are excellent in flexibility and longevity and that can minimize dust generation.

In addition, although the film-like first diaphragm described above is very thin, since the first diaphragm is joined to the shaft-like connecting member at its central portion by laser welding, the first diaphragm is axially connected at its central portion. The shaft-like connecting member can be easily connected to the central portion of the diaphragm by laser welding without having a connecting portion required for connection with the like-shaped connecting member.

Further, according to the description of claim 2, the diaphragm control valve according to the present invention is different from the diaphragm control valve described in claim 1 in that the first diaphragm receives the set pressure generated in the first pressure regulating chamber and With the second diaphragm receiving the set pressure generated in the second pressure regulating chamber, the first diaphragm and the second diaphragm are separably connected to each other in accordance with fluctuations in the liquid pressure of the liquid on the inflow side. By controlling the opening degree between the valve body portion and the annular valve seat portion to a constant opening degree via the shaft-like connecting member and the shaft-like valve body member, a constant flow rate corresponding to the constant opening degree is obtained. , the liquid on the inflow side flows out to the outflow side through the inflow passage, the second liquid chamber, the annular valve seat portion, the central communication passage, the first liquid chamber and the outflow passage.

According to such a configuration, unlike the invention described in claim 1, the control valve includes the first diaphragm, the shaft-like connecting member and the shaft-like valve body member which are separably connected to each other, and the second diaphragm. Even if the separable structure is configured with this, the control valve is operated under both set pressures, and the valve body moves along with the displacement of the separable structure in response to fluctuations in the hydraulic pressure of the liquid flowing in from the inflow side. It is possible to control the degree of opening of the portion with respect to the annular valve seat portion to a constant degree of opening, in other words, the flow rate of the liquid from the inflow side to a constant flow rate. Other functions and effects are the same as those of the first aspect of the invention.

Further, according to the description of claim 3, the present invention provides a diaphragm control valve according to claim 1 or 2,
The first diaphragm member is characterized by comprising a fluororesin reinforcing annular body (200b) joined by laser welding to the other side or the one side of the first diaphragm along the outer periphery thereof. .

According to this, even if the first diaphragm is thin like a film and is difficult to handle, the reinforcing ring-shaped body can be formed by laser welding the outer peripheral portion of the first diaphragm and the reinforcing ring-shaped body as described above. However, it can exhibit a good reinforcing function for the first diaphragm. Therefore, in addition to the function and effect of the first aspect of the invention, it is possible to achieve the function and effect that even if the diaphragm is thin, it can be easily handled without bending.

Further, according to the description of claim 4, the present invention provides a diaphragm control valve according to any one of claims 1 to 3,
The first diaphragm member is coaxially joined to the first diaphragm from the one side surface thereof by laser welding so as to suppress the deflection of the first diaphragm and restrict the movable range of the first diaphragm. It is characterized by comprising a plate-shaped auxiliary member (290).

According to this , the plate-shaped auxiliary member is coaxially joined to the first diaphragm from the one side surface by laser welding on the surface on the side of the first diaphragm. Thereby, the first diaphragm can be bent and displaced satisfactorily without bending . As a result, the invention described in any one of claims 1 to 3 can be achieved even better.

Further, according to the description of claim 5, the present invention provides a diaphragm control valve according to any one of claims 1 to 4,
The first diaphragm is characterized in that it is formed into a film by extrusion molding or compression molding PFA together with the second diaphragm.

According to this, the first diaphragm and the second diaphragm are formed in a film form by extrusion molding or compression molding of PFA, and the first diaphragm and the second diaphragm are formed by cutting. In particular, the first diaphragm and the second diaphragm have a highly smooth surface that can suppress even dust generation such as particles of several nm size to the minimum (minimum). It is possible to form the first diaphragm and the second diaphragm excellent in chemical resistance, low elution, flexibility and long life.

Further, as described above, since the first diaphragm and the second diaphragm are formed in a film shape by extruding or compressing PFA, the first diaphragm and the second diaphragm are centered on the curved displacement portion. Crystallization can be made uniform, and the service life of the first diaphragm and the second diaphragm can be further extended. As described above, the effects of the invention described in any one of claims 1 to 4 can be further improved.

Further, according to the description of claim 6, the present invention provides a diaphragm control valve according to claim 5,
The first diaphragm, together with the second diaphragm, has a thickness within the range of 0.1 (mm) or more and 0.6 (mm) or less.

Thereby, the effects of the invention described in claim 5 can be achieved more reliably. Here, the reason why the thickness of the first diaphragm and the second diaphragm is set to 0.1 (mm) or more is that if the thickness is less than 0.1 (mm), the first diaphragm and the second diaphragm are too thin and easily broken. be. The reason why the thickness is 0.6 (mm) or less is that if the first diaphragm and the second diaphragm are thicker than 0.6 (mm), the curved displacement portion of the first diaphragm and the second diaphragm is too hard and sensitive. This is because the first diaphragm and the second diaphragm are likely to be broken such as cracks.

It should be noted that the symbols in parentheses of the above means indicate correspondence with specific means described in the embodiments described later.

1 is a longitudinal sectional view showing a first embodiment of a diaphragm control valve according to the present invention; FIG. It is a sectional view of the 1st diaphragm member in a 1st embodiment of the above. It is a sectional view of the 2nd diaphragm member in a 1st embodiment of the above. FIG. 5 is a cross-sectional view showing the essential parts of a second embodiment of a diaphragm control valve according to the present invention; FIG. 5 is a vertical cross-sectional view showing a third embodiment of a diaphragm control valve according to the present invention; It is a sectional view of the 1st diaphragm member in a 3rd embodiment of the above. FIG. 11 is a cross-sectional view showing the essential parts of a diaphragm control valve according to a fourth embodiment of the present invention; FIG. 10 is a longitudinal sectional view showing a fifth embodiment of a diaphragm control valve according to the present invention; FIG. 11 is a vertical cross-sectional view showing a sixth embodiment of a diaphragm control valve according to the present invention;

Hereinafter, each embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 shows a first embodiment of a diaphragm control valve to which the present invention is applied. The control valve is applied to a semiconductor manufacturing apparatus that manufactures semiconductor elements. The semiconductor manufacturing apparatus manufactures semiconductor wafers and semiconductor devices using the semiconductor wafers by using liquid supplied from a liquid supply source (not shown) through a pump (not shown) to a piping route. Here, the pump discharges the liquid from the liquid supply source into the piping path. Further, the liquid refers to a liquid such as a high-purity chemical liquid or ultrapure water, and is required to be clean in view of the characteristics of the semiconductor manufacturing apparatus.

The control valve, for example, is interposed in the piping path on the discharge side of the pump, and the control valve plays a role of controlling the liquid discharged from the pump to a constant flow rate to flow out. .

The control valve, as shown in FIG. 1, comprises a tubular housing 100, and a first diaphragm member 200 and a second diaphragm member 300 assembled in the tubular housing 100. As shown in FIG.

The tubular housing 100 is composed of a bottom housing member 100a, a middle housing member 100b, and an upper housing member 100c.

The bottom side housing member 100a is composed of a bottom wall 110 and a peripheral wall 120. The bottom wall 110 has a rectangular cross section. The bottom wall 110 has an air supply passage portion 111 and an exhaust hole portion 112, and the air supply passage portion 111 communicates with the outside of the bottom wall 110 so that the inside of the peripheral wall 120 communicates with the outside of the bottom wall 110. It is formed so as to extend in an L-shape to the left side in FIG. 1 from the upper central opening. The exhaust hole portion 112 is formed through the bottom wall 110 in the thickness direction so that the inside of the peripheral wall 120 communicates with the outside of the bottom wall 110 on the right side of the air supply passage portion 111 .

In the first embodiment, the air supply passage portion 111 receives a compressed air flow from a compressed air flow supply source (hereinafter also referred to as a second compressed air flow supply source) (not shown) into a second pressure regulating chamber Ra (later described). ), while the exhaust hole portion 112 serves to exhaust the compressed air flow supplied into the second pressure regulating chamber Ra to the outside.

The peripheral wall 120 has a rectangular cross section, and extends coaxially upward in FIG. 1 from the bottom wall 110 . The peripheral wall 120 has an opening wall portion 120 a formed by an inner annular wall portion 121 and an outer annular wall portion 122 . The inner annular wall portion 121 is annularly formed at the inner peripheral portion of the opening wall portion 120a. is also formed to protrude upward in an annular shape.

As shown in FIG. 1, the middle housing member 100b is coaxially attached to the bottom housing member 100a from above. 150 , an inflow tube 160 and an outflow tube 170 .

The middle wall 130 has a rectangular cross section, and has an inflow-side communication passage 131 and an outflow-side communication passage 132 . The inflow-side communication passage 131 is formed in an L shape within the left side portion of the middle wall 130 so as to communicate the inflow pipe 160 with the inside of the lower peripheral wall 140 (described later). On the other hand, the outflow-side communication passage 132 is formed in an L-shape in the right portion of the middle wall 130 so as to communicate the inside of the upper peripheral wall 150 with the outflow cylinder 170 .

Further, the middle wall 130 has a central communication passage 133 , and the central communication passage 133 is coaxially formed through the central portion of the middle wall 130 . The central communicating path 133 communicates the inside of the upper peripheral wall 150 with the inside of the lower peripheral wall 140 (described later), and the central communicating path 133 is formed at the open end on the lower peripheral wall 140 side. to form an annular valve seat portion 133a.

The lower peripheral wall 140 extends coaxially downward from the outer peripheral portion of the middle wall 130, and the lower peripheral wall 140 is an opening wall of the peripheral wall 120 of the bottom housing member 100a at its opening wall portion 140a. It is coaxially attached to the portion 120a. Specifically, the opening wall portion 140a of the lower peripheral wall 140 has an inner annular wall portion 141 and an outer annular wall portion 142, and the inner annular wall portion 141 protrudes downward from the outer annular wall portion 142. , so as to face the inner annular wall portion 121 of the peripheral wall 120 at the inner peripheral portion of the opening wall portion 140a. The outer annular wall portion 142 is annularly formed so as to face the outer annular wall portion 122 of the peripheral wall 120 at the outer peripheral side portion of the opening wall portion 140a.

Thus, the inner annular wall portion 141 of the lower peripheral wall 140 is coaxially fitted in the outer annular wall portion 122 of the peripheral wall 120 , and the outer peripheral portion of the second diaphragm member 300 intervenes inside the peripheral wall 120 . Lower peripheral wall 140 is assembled to peripheral wall 120 by engaging annular wall portion 121 and engaging, at outer annular wall portion 142 , onto outer annular wall portion 122 of peripheral wall 120 . Thereby, the lower peripheral wall 140 and the peripheral wall 120 form an accommodation chamber R (hereinafter also referred to as a second accommodation chamber R) that accommodates the second diaphragm 300 therein.

The inflow tube 160 extends outward from the inner wall 130 from the outer end opening of the inflow-side communication path 131, and the inflow tube 160 communicates the inflow-side communication path 131 to the upstream side of the piping route. play a role in making The outflow tube 170 extends outward from the outer end opening of the outflow side communication path 132, and the outflow tube 170 serves to communicate the outflow side communication path 132 to the downstream side of the piping route. .

The upper peripheral wall 150 has a rectangular cross section, and extends coaxially upward in FIG. 1 from the middle wall 130 . The upper peripheral wall 150 has an opening wall portion 150 a formed by an inner annular wall portion 151 and an outer annular wall portion 152 . The inner annular wall portion 151 is annularly formed at the inner peripheral portion of the opening wall portion 150a. is also formed to protrude upward in an annular shape.

The upper housing member 100c is composed of a top wall 180 and a peripheral wall 190. As shown in FIG. The upper wall 180 is formed in a rectangular plate shape in cross section, and is formed with an air supply hole portion 181 and an air exhaust hole portion 182 as shown in FIG.

In the first embodiment, the air supply hole portion 181 receives a compressed air flow from a compressed air flow supply source (hereinafter also referred to as a first compressed air flow supply source) (not shown) into a first pressure regulating chamber Sa (to be described later). ), and the exhaust hole portion 182 serves to exhaust the compressed air flow supplied into the first pressure regulating chamber Sa to the outside.

The peripheral wall 190 is formed to coaxially extend downward from the outer peripheral portion of the upper wall 180, and the peripheral wall 190 has an opening facing the opening wall portion 150a of the upper peripheral wall 150 of the middle housing member 100b. It is formed to have a wall portion 190a. The opening wall portion 190 a has an inner annular wall portion 191 and an outer annular wall portion 192 facing the inner annular wall portion 151 and the outer annular wall portion 152 of the opening wall portion 150 a of the upper peripheral wall 150 .

The inner annular wall portion 191 is formed so as to annularly protrude downward from the outer annular wall portion 192 at the inner peripheral portion of the opening wall portion 190a. It faces the inner annular wall portion 151 of the upper peripheral wall 150 through the outer peripheral portion of the member 200 . On the other hand, the outer annular wall portion 192 is formed so as to protrude downward so as to face the outer annular wall portion 152 of the upper peripheral wall 150 at the outer peripheral side portion of the opening wall portion 190a.

Thus, the upper housing member 100c is assembled to the middle housing member 100b so that the opening wall portion 190a of the peripheral wall 190 is engaged with the opening wall portion 150a of the upper peripheral wall 150 via the first diaphragm member 200. It is Here, the upper housing member 100c is arranged so that the inner annular wall portion 191 of the peripheral wall 190 faces the inner annular wall portion 151 of the upper peripheral wall 150 via the outer peripheral portion of the first diaphragm member 200. It is assembled to the middle housing member 100b by engaging the outer annular wall portion 152 of the upper peripheral wall 150 at the wall portion 192 . As a result, the upper housing member 100c, together with the middle housing member 100b, has an accommodation chamber S (hereinafter, also referred to as a first accommodation chamber S) that accommodates the first diaphragm member 200 inside each of the upper peripheral wall 150 and the peripheral wall 190. configure.

The first diaphragm member 200, as shown in either FIG. 1 or FIG. 2, is composed of a diaphragm 200a (hereinafter also referred to as the first diaphragm 200a), a reinforcing annular body 200b, and a shaft-like connecting member 200c. . The first diaphragm 200a is integrally formed with an outer peripheral portion 210, a central portion 220 and a curved displacement portion 230. As shown in FIG. Here, the curved displacement portion 230 is annularly formed concentrically between the outer peripheral portion 210 and the central portion 220 .

Thus, the first diaphragm 200a is located on the inner peripheral side of the outer annular wall portion 152 of the opening wall portion 150a of the upper peripheral wall 150 of the middle housing member 100b together with the reinforcing annular body 200b at the outer peripheral portion 210 thereof. In a state in which the reinforcing annular body 200b is positioned on the lower side, it is engaged with the inner annular wall portion 151 of the opening wall portion 150a of the upper peripheral wall 150, and is engaged with the opening of the peripheral wall 190 of the upper housing member 100c. It is sandwiched between the inner annular wall portion 191 of the wall portion 190 a and the inner annular wall portion 151 of the opening wall portion 150 a of the upper peripheral wall 150 .

As a result, the first diaphragm 200a is positioned inside the first housing chamber S at the central portion 220 and the curved displacement portion 230, and is located inside the pressure regulating chamber Sa (hereinafter referred to as the first pressure regulating chamber) at the upper wall 180 side. The inside of the first housing chamber S is partitioned so as to form a chamber Sa) and to form a liquid chamber Sb (hereinafter also referred to as a first liquid chamber Sb) on the middle wall 130 side. Accordingly, the first pressure regulating chamber Sa is maintained at the set pressure based on the compressed air flow supplied at a constant pressure from the first compressed air flow supply source through the air supply hole 181. It is designed to be This means that the set pressure acts on the upper surface 240 of the first diaphragm 200a.

Further, the liquid discharged from the pump flows into the first liquid chamber Sb through the inflow cylinder 160 and the inflow side communication passage 131 of the middle wall 130 via the upstream side of the piping path. As a result, the liquid generates liquid pressure acting on the lower surface 250 of the first diaphragm 200a within the first liquid chamber Sb.

The first diaphragm 200a is formed by extruding a tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer (PFA) so as to integrally have the outer peripheral portion 210, the central portion 220, and the curved displacement portion 230 described above. , is formed as a disk-shaped and film-shaped diaphragm.

The grounds for adopting PFA as the material for forming the first diaphragm 200a in the first embodiment will be described.

Due to its configuration as a control valve, the first diaphragm 200a is in contact with high-purity chemicals such as highly corrosive chemicals such as strong acids and strong alkalis among the liquids flowing through the piping path. It is desirable to have excellent chemical resistance such as acid resistance and alkali resistance.

In addition, since the elution of metal components and organic components from the first diaphragm 200a and other constituent members of the control valve is not permitted, it is desirable to employ a fluororesin having a low elution property at least as a material for forming the diaphragm. .

Further, since the first diaphragm 200a repeats bending displacement each time the control valve is opened and closed, it is desirable that at least flexibility and longevity are excellent.

Therefore, in the first embodiment, PFA is excellent in chemical resistance, low elution property, heat resistance and corrosion resistance, and can ensure flexibility and long life. Adopted. In addition, in the first embodiment, PFA is used as a material for forming the tubular housing 100 as well.

The first diaphragm 200a is made of PFA and has a thickness within a predetermined thickness range, for example, 0.5 (mm), as a film-like diaphragm. In the first embodiment, the predetermined thickness range refers to a thickness range of 0.1 (mm) or more and 0.6 (mm) or less. Here, the reason why the thickness is set to 0.1 (mm) or more is that if the thickness is less than 0.1 (mm), the first diaphragm 200a is too thin and easily broken. The reason why the thickness is set to 0.6 (mm) or less is that if the thickness of the first diaphragm 200a is greater than 0.6 (mm), the curved displacement portion of the first diaphragm 200a is too hard to be sensitively displaced. This is also because the first diaphragm 200a is prone to breakage such as cracks.

The reason for adopting the extrusion molding method using PFA in forming the first diaphragm 200a as described above is based on the following grounds.

For example, when a diaphragm is formed by cutting a material made of PFA, cutting marks are formed on the surface of the diaphragm. Therefore, when the diaphragm made by such cutting comes into contact with the liquid flowing in the first liquid chamber Sb of the control valve, particles, for example, minute particles with a size of several nanometers, are generated due to the cutting marks of the diaphragm. However, if the dust comes off the diaphragm and mixes with the liquid, the liquid cannot be kept clean. Consequently, when the liquid is returned to the first liquid supply source as described above, the liquid discharged from the pump into the piping path cannot be kept clean.

This leads to poor quality of products manufactured by the semiconductor manufacturing apparatus, for example, silicon wafers having a wiring pitch of 10 (nm) or less. For this reason, it is necessary to reliably prevent particles from entering the liquid in the control valve, for example, even particles with a size of several nanometers from entering the liquid.

In addition, it is difficult to form a diaphragm into a film form by injection molding of PFA, and even if it can be formed into a film form, it is difficult to form a diaphragm with excellent flexibility and a long life. is.

Therefore, in the first embodiment, the first diaphragm 200a is formed into a film shape by extrusion molding of PFA. As a result, the film-like diaphragm extruded by the extruder has a very good smooth surface on each surface, that is, a particle of several nanometers in size formed so as to have a smooth surface. It is a diaphragm that can minimize dust generation, and can be formed as a diaphragm that has excellent chemical resistance, low elution, flexibility, and a long life.

The reinforcing annular body 200b is for reinforcing the film-shaped diaphragm 200a, and the reinforcing annular body 200b is joined by laser welding from the lower surface 250 side of the diaphragm 200a along the outer peripheral portion 210 of the diaphragm 200a. there is As a result, the reinforcing annular body 200b is integrally formed with the outer peripheral portion 210 of the diaphragm 200a, positioned below the outer peripheral portion 210, and together with the outer peripheral portion 210, the upper peripheral wall of the middle housing member 100b. 150, and is sandwiched between the inner annular wall portion 151 of the upper peripheral wall 150 and the inner annular wall portion 191 of the peripheral wall 190 of the upper housing member 100c. there is

In this case, even if the first diaphragm 200a is thin and difficult to handle, the reinforcing ring-shaped body 200b can be formed by laser welding the outer peripheral portion 210 of the first diaphragm 200a and the reinforcing ring-shaped body 200b. , the first diaphragm 200a satisfactorily exerts a reinforcing function from the outer peripheral portion 210 side thereof, and the first diaphragm 200a can be easily moved to the inner peripheral side of the outer annular wall portion 152 of the upper peripheral wall 150 of the middle housing member 100b. can be fitted. Accordingly, the first diaphragm 200a can be well engaged with the reinforcing ring 200b on the inner ring wall 151 and clamped as described above.

In the first embodiment, the reinforcing annular body 200b is formed by injection-molding PFA into a columnar shape and then cutting it into an annular shape. Here, the reinforcing annular body 200b has an outer diameter equal to the outer diameter of the first diaphragm 200a. It is set to each value suitable for reinforcement and easy handling.

As shown in either FIG. 1 or FIG. 2, the shaft-like connecting member 200c coaxially extends from the central portion 220 of the first diaphragm 200a toward a shaft-like valve body member 300c (to be described later). As shown in FIG. 2, the shaft-shaped connecting member 200c is formed by injection molding using PFA so as to integrally have a disk-shaped base portion 260, a truncated cone portion 270 and a connecting shaft portion 280. As shown in FIG.

In the axial connecting member 200c, the disk-shaped base portion 260 is joined to the central portion 220 of the first diaphragm 200a by laser welding on the lower surface 250 side of the first diaphragm 200a. In the first embodiment, the shaft-like connecting member 200c is joined to the central portion 220 of the first diaphragm 200a by laser welding at the disc-shaped base portion 260 as described above. 200c plays a role of favorably reinforcing the first diaphragm 200a from the central portion 220 side at the disk-shaped base portion 260 thereof. As a result, fitting the first diaphragm 200a to the inner peripheral side of the outer annular wall portion 152 of the upper peripheral wall 150 of the middle housing member 100b as described above is performed by the shaft-like connecting member 200c. With 260, in conjunction with the reinforcing ring 200b, this can be achieved more easily.

The truncated cone portion 270 extends from the central portion of the disk-shaped base portion 260 in a tapered shape so as to coaxially face the shaft-shaped valve body member 300c. The connecting shaft portion 280 axially extends from the central portion of the extending end portion 271 of the truncated cone portion 270 so as to coaxially face the shaft-shaped valve body member 300c. , a female screw hole portion 281 is formed. In the first embodiment, the female threaded hole portion 281 is coaxially formed in the connecting shaft portion 280 from the extending end thereof. The shaft-like connecting member 200c configured in this way constitutes the first diaphragm member 200 integrally with the diaphragm 200a and the reinforcing annular body 200b.

As shown in FIGS. 1 and 3, the second diaphragm member 300 comprises a diaphragm 300a (hereinafter also referred to as the second diaphragm 300a), a reinforcing annular body 300b, and a shaft-like valve body member 300c. The second diaphragm 300 a is integrally formed with an outer peripheral portion 310 , a central portion 320 and a curved displacement portion 330 . Here, the curved displacement portion 330 is annularly and concentrically formed between the outer peripheral portion 310 and the central portion 320 .

Thus, the second diaphragm 300a is located on the inner peripheral side of the outer annular wall portion 122 of the opening wall portion 120a of the peripheral wall 120 of the bottom housing member 100a together with the reinforcing annular body 300b at the outer peripheral portion 310 thereof. In a state in which the reinforcing annular body 300b is positioned on the upper side, it engages on the inner annular wall portion 121 of the opening wall portion 120a of the peripheral wall 120, It is sandwiched between the inner annular wall portion 141 and the inner annular wall portion 121 of the opening wall portion 120 a of the peripheral wall 120 .

As a result, the second diaphragm 300a is located inside the second housing chamber R at the central portion 320 and the curved displacement portion 330, and is located inside the pressure regulating chamber Ra (hereinafter referred to as the second pressure regulating chamber) at the bottom wall 110 side. The inside of the second storage chamber R is partitioned so as to form a chamber Ra) and to form a liquid chamber Rb (hereinafter also referred to as a second liquid chamber Rb) on the middle wall 130 side. Along with this, the second pressure regulating chamber Ra is internally operated based on the compressed air flow supplied at a constant pressure from the second compressed air flow supply source (not shown) through the air supply communication passage 111. , is maintained at the set pressure. This means that the set pressure acts on the lower surface 350 of the diaphragm 300a.

Also, the second liquid chamber Rb can communicate with the inside of the first liquid chamber Sb via the annular valve seat portion 133 a of the middle wall 130 and the central communication passage 133 . Accordingly, the liquid in the second liquid chamber Rb flows through the central communication passage 133 from between the seating portion 373a (to be described later) of the valve body portion 370b of the shaft-like valve body member 300c and the annular valve seat portion 133a. The liquid can flow inside the first liquid chamber Sb.

As a result, the liquid generates liquid pressure acting on the upper surface 340 of the diaphragm 300a in the second liquid chamber Rb, and the liquid flows from between the seating portion 373a of the shaft-like valve body member 300c and the annular valve seat portion 133a. The liquid flows through the central communication passage 133, the first liquid chamber Sb, the outflow side communication passage 132, and the outflow cylinder 170 to the downstream side of the piping route. Here, the second diaphragm 300a has the same configuration as the first diaphragm 200a and is formed into a film by PFA extrusion molding based on the same grounds as the first diaphragm 200a described above.

The reinforcing annular body 300b is for reinforcing the film-like second diaphragm 300a from its outer peripheral side, and the reinforcing annular body 300b extends along the outer peripheral part 310 of the second diaphragm 300a. are joined by laser welding from the upper surface 340 side.

Along with this, the reinforcing annular body 300b is formed integrally with the outer peripheral portion 310 of the second diaphragm 300a, positioned above the outer peripheral portion 310, and together with the outer peripheral portion 310 of the bottom side housing member 100a. It is fitted on the inner peripheral side of the outer annular wall portion 122 of the peripheral wall 120 . Here, the reinforcing annular body 300b plays a role of favorably reinforcing the second diaphragm 300a from its outer peripheral side. Therefore, even if the second diaphragm 300a is thin and difficult to handle, the second diaphragm 300a, together with the reinforcing ring-shaped body 300b, can be used as the bottom housing member 100a under the reinforcing function of the reinforcing ring-shaped body 300b as described above. It can be easily fitted to the inner peripheral side of the outer annular wall portion 122 of the peripheral wall 120 .

Therefore, under such fitting, the second diaphragm 300a, together with the reinforcing annular body 300b, is formed at the outer peripheral portion 310 of the inner annular wall portion 141 of the lower peripheral wall 140 and the peripheral wall of the bottom housing member 100a. 120 and an inner annular wall portion 121 thereof. In addition, in the first embodiment, the radial width of the reinforcing annular body 300b is set wider than the radial width of the reinforcing annular body 200b described above. The reinforcing ring-shaped body 300b is made of PFA, like the reinforcing ring-shaped body 200b.

The shaft-like valve body member 300c has a circular substrate 360 and a rod 370, as shown in FIG. In the first embodiment, the shaft-shaped valve member 300c is made of PFA.

The circular substrate 360 is joined to the central portion 320 of the second diaphragm 300a by laser welding from the upper surface 340 side of the second diaphragm 300a. In the first embodiment, the shaft-shaped valve body member 300c is joined to the central portion 320 of the second diaphragm 300a by laser welding at its circular substrate 360 as described above. The circular substrate 360 of 300c serves to reinforce the second diaphragm 300a from its central portion 320 side. As a result, fitting the second diaphragm 300a to the inner peripheral side of the outer annular wall portion 122 of the peripheral wall 120 of the bottom housing member 100a as described above is performed by the shaft-like valve body member 300c and the circular substrate 360. Therefore, in combination with the reinforcing annular body 3200b, it can be achieved more easily.

Further, the rod 370 coaxially extends from the central portion of the circular substrate 360 into the central communication passage 133 of the inner wall 130 so as to face the shaft-like connecting member 200c. The side rod portion 370a, the valve body portion 370b, and the tip end side rod portion 370c are integrally formed.

The proximal rod portion 370a coaxially extends from the central portion of the circular substrate 360 so as to face the shaft-like connecting member 200c. As shown in FIG. 3, the valve body portion 370b includes a cylindrical portion 371 and a lower truncated cone portion extending coaxially downward from the axially lower end portion of the cylindrical portion 371 in a tapered shape. 372 and an upper truncated cone portion 373 extending coaxially upward from the axially upper end portion of the cylindrical portion 371 in a tapered shape.

Thus, the valve body portion 370b has an annular valve seat portion 133a (to be described later) and a . Together, they form a valve portion. Accordingly, the valve portion is closed by the seat portion 373a of the upper truncated cone portion 373 being seated on the annular valve seat portion 133a. This means that the control valve is closed. Further, the valve portion is opened by separating the seating portion 373a of the upper truncated cone portion 373 from the annular valve seat portion 133a. This means that the control valve is opened. Here, a lower open end portion 133a of the central communication passage 133 of the middle wall 130 is formed as an annular valve seat portion 133a.

The tip-side rod portion 370c is integrally formed of a large-diameter shaft portion 374 and a male thread portion 375, and the large-diameter shaft portion 374 tapers to the end of the upper truncated cone portion 373 of the valve body portion 370b. extends coaxially upward from the The male threaded portion 375 coaxially extends from the central portion of the large-diameter shaft portion 374 toward the shaft-like connecting member 200c. It is coaxially fastened within the internally threaded bore 281 . Along with this, the large-diameter shaft portion 374 engages with the outer peripheral portion of the connecting shaft portion 280 at its outer peripheral portion. Thereby, the shaft-like valve body member 300c is integrally connected or coupled with the shaft-like connecting member 200c.

In the first embodiment configured as described above, when a semiconductor device is manufactured by the semiconductor manufacturing apparatus, a compressed air flow is supplied from the first compressed air flow supply source to the first pressure regulating chamber Sa at the constant pressure. When the air is supplied through the air supply hole 181 of the upper housing member 100c, the set pressure (hereinafter also referred to as the first set pressure) is generated in the first pressure regulating chamber Sa. On the other hand, when the compressed air flow is supplied from the second compressed air flow supply source at the constant pressure into the second pressure regulating chamber Ra through the communicating passage portion 111 of the bottom housing member 100a, the set pressure ( hereinafter also referred to as a second set pressure) is generated in the second pressure regulating chamber Ra.

Here, the shaft-like valve body member 300c of the second diaphragm member 300 is coaxially inserted at its male threaded portion 375 into the female threaded hole portion 281 of the connecting shaft portion 280 of the shaft-like connecting member 200c of the first diaphragm member 200. tightened. This means that the first diaphragm 200a and the second diaphragm 300a are integrated together with the shaft-like connecting member 200c and the shaft-like valve member 300c by mutual coupling of the shaft-like connecting member 200c and the shaft-like valve member 300c. It means that it has become a body.

Under such a configuration, in the first embodiment, the constant pressure of the first compressed air flow and the constant pressure of the second compressed air flow are controlled by the control valves to the discharge from the pump. In accordance with the displacement of the integrated structure due to fluctuations in the hydraulic pressure of the liquid, the degree of opening of the valve body portion 370b with the annular valve seat portion 133a (the degree of opening of the valve portion) is controlled at a constant interval to maintain a constant flow rate. It is selected so that it flows out as a liquid of Accordingly, the main set pressure in the first pressure regulating chamber Sa and the auxiliary set pressure in the second pressure regulating chamber Ra are set to the constant pressure of the first compressed air flow and the constant pressure of the second compressed air flow, respectively. It is set with the above constant pressure.

Thus, as described above, when the liquid flows into the second liquid chamber Rb and the first liquid chamber Sb, the hydraulic pressure of the liquid acts on the second diaphragm 300a from the second liquid chamber Rb side and the first diaphragm 200a from the first liquid chamber Sb side.

In accordance with this, the control valve operates in the above-described integrated structure under the set pressure in the first pressure regulating chamber Sa and the set pressure in the second pressure regulating chamber Ra, which act to face each other. The distance (valve opening) is controlled at regular intervals. This means that the control valve controls the discharge liquid from the pump to a constant flow rate corresponding to the constant distance between the seat portion 373a of the valve body portion 370b and the annular valve seat portion 133a, thereby 131 , the second liquid chamber Rb, the central communication passage 133 , the first liquid chamber Sb, and the outflow-side communication passage 132 to flow out of the outflow tube 170 .

In such a state, when the liquid pressure of the liquid discharged from the pump fluctuates, the control valve causes the integrated structure to operate under both of the set pressures. The opening of the seat portion 373a with respect to the annular valve seat portion 133a is controlled to be displaced so as to maintain the constant opening. In other words, under both set pressures, the control valve displaces the integrated structure according to fluctuations in the liquid pressure of the liquid discharged from the pump, and causes the liquid to be discharged at a constant flow rate to the outflow side. control to flow out to

Here, each diaphragm 200a, 300a is a film-like diaphragm formed by extrusion molding of PFA, as described above. Therefore, both surfaces of the diaphragms 200a and 300a are excellent smooth surfaces.

Therefore, even if the control valve is in an operating state, particles such as those caused by cutting marks are separated from the first diaphragm 200a and the second diaphragm 300a by contact with the liquid of the first diaphragm 200a and the second diaphragm 300a. It is possible to minimize (minimize) even the mixing of minute particles with a size of several nanometers into the liquid. Moreover, this is also true even if the shaft-like connecting member 200c is seated on the annular valve seat portion 133a or separated from the annular valve seat portion 133a in the operating state of the control valve.

As described above, in the control valve, the liquid flowing in the first liquid chamber Sb and the second liquid chamber Rb can minimize even minute particles of several nanometers in size, as described above. As a result, the liquid is kept substantially clean, and flows through the annular valve seat portion 133a, the central communicating passage 133, the first liquid chamber Sb, the outflow side communicating passage 132, and the outflow tube 170 to the downstream side of the piping route. .

Therefore, in the manufacture of semiconductor devices, even if the liquid flowing out to the downstream side of the piping path as described above flows along the surface of a semiconductor wafer having a wiring pitch of 10 (nm) or less, for example, particles of several nm size does not adhere to the surface of the semiconductor wafer and cause short-circuiting between wirings or other abnormalities. As a result, the quality of the manufactured semiconductor device can be favorably maintained.

In addition, since the film-like first diaphragm 200a and the second diaphragm 300a are formed by extrusion molding of PFA as described above, it is possible to minimize the generation of particles of several nanometers in size and to have flexibility. It can be formed as a diaphragm that can maintain excellent longevity. Therefore, even if the control valve having the first diaphragm 200a and the second diaphragm 300a is applied to a semiconductor manufacturing apparatus, the bending operation of the first diaphragm 200a and the second diaphragm 300a can be favorably maintained for a long period of time. , the control valve can be applied to semiconductor manufacturing equipment and can maintain good functions over a long period of time.

(Second embodiment)
FIG. 4 shows the main part of the second embodiment of the invention. In the second embodiment, the first diaphragm member 200 described in the first embodiment is provided with a disk-shaped auxiliary member 290 in addition to the diaphragm 200a, the reinforcing annular body 200b, and the shaft-shaped connecting member 200c. there is

The auxiliary member 290 is made of PFA and has a disc shape, and serves to regulate the movable range of the bending displacement portion 230 of the diaphragm 200a. The auxiliary member 290 is coaxially joined to the first diaphragm 200a at its lower surface by laser welding from its upper surface 240 side. The outer diameter and thickness of the auxiliary member 290 are set so as to suppress the bending of the first diaphragm 200a and restrict the movable range of the first diaphragm 200a. Other configurations are the same as those of the first embodiment.

In the second embodiment configured as described above, the auxiliary member 290 is joined to the first diaphragm 200a by laser welding as described above, so in the first diaphragm member 200, the first diaphragm 200a , the bending displacement portion 230 can be bent satisfactorily without bending. Other configurations, operations, and effects of the control valve are the same as those of the first embodiment.

(Third embodiment)
FIG. 5 shows a third embodiment of a diaphragm control valve according to the invention. In the third embodiment, the diaphragm type control valve, as shown in either FIG. 5 or FIG. 6, joins the reinforcing annular body 200b to the outer peripheral portion 210 of the first diaphragm 200a from the upper surface 240 side by laser welding. This first diaphragm member is adopted in place of the first diaphragm member 200 described in the first embodiment. The first diaphragm member referred to in the third embodiment is also indicated by reference numeral 200 as in the first embodiment.

In the control valve of the third embodiment, the first diaphragm member 200 is composed of a first diaphragm 200a, a reinforcing annular body 200b and a shaft-like connecting member 200c, as in the first embodiment. Also in the third embodiment, the shaft-like connecting member 200c is laser-welded from the lower surface 250 side to the central portion 220 of the first diaphragm 200a at its disk-like base portion 260, as in the first embodiment. It is joined (see FIG. 6). Further, unlike the first embodiment, the reinforcing annular body 200b is joined to the outer peripheral portion 210 of the diaphragm 200a by laser welding from the upper surface 240 side (see FIG. 6). Other configurations are the same as those of the first embodiment.

In the third embodiment configured as described above, in the first diaphragm member 200 configured as described above, the first diaphragm 200a is positioned on the upper side of the reinforcing annular body 200b. At the portion 210, it is fitted to the inner peripheral side of the outer annular wall portion 152 of the opening wall portion 150a of the upper peripheral wall 150 of the intermediate housing member 100b together with the reinforcing annular body 200b. It is sandwiched between the inner annular wall portion 151 of the opening wall portion 150a of the upper housing member 100c and the inner annular wall portion 191 of the opening wall portion 190a of the peripheral wall 190 of the upper housing member 100c.

In this case, as described above, even if the reinforcing annular body 200b is joined to the first diaphragm 200a from the upper surface 240 side by laser welding, with such a joining structure, the first diaphragm 200a is thin. Even if it is difficult, the reinforcing annular body 200b exhibits a good reinforcing function for the first diaphragm 200a, and the first diaphragm 200a is positioned on the inner peripheral side of the outer annular wall portion 152 of the upper peripheral wall 150 of the middle housing member 100b. can be easily fitted to Along with this, the first diaphragm 200a satisfactorily sits on the inner annular wall portion 151 together with the reinforcing annular body 200b, and can be clamped as described above. Other configurations, operations, and effects of the control valve are the same as those of the first embodiment.

(Fourth embodiment)
FIG. 7 shows the main part of the fourth embodiment of the invention. In the fourth embodiment, the first diaphragm member 200 described in the third embodiment is added to the first diaphragm 200a, the reinforcing annular body 200b, and the shaft-like connecting member 200c in the second embodiment. It has the disk-shaped auxiliary member 290 mentioned.

Unlike the second embodiment, the auxiliary member 290 is coaxially joined to the first diaphragm 200a from the upper surface 240 side by laser welding on the inner peripheral side of the reinforcing annular body 200b on the lower surface. there is Other configurations are the same as those of the second or third embodiment.

In the fourth embodiment configured as described above, unlike the second embodiment, the auxiliary member 290 is provided on the inner peripheral side of the reinforcing ring-shaped member 200b to apply laser light to the first diaphragm 200a from the upper surface 240 side thereof. Even if the first diaphragm member 200 is joined by welding, the first diaphragm 200a of the first diaphragm member 200 can be bent satisfactorily at the bending displacement portion 230 without bending. The rest of the configuration, operation and effects of the control valve are the same as those of the second or third embodiment.

(Fifth embodiment)
FIG. 8 shows a fifth embodiment of a diaphragm control valve according to the present invention. In the fifth embodiment, the shaft-like connecting member 200c of the first diaphragm member 200 described in the first embodiment has a trapezoidal vertical cross-sectional shape instead of the female threaded hole 281 at the connecting shaft portion 280. The second diaphragm member 300 has a recess 282, and the second diaphragm member 300 has a protrusion 370d having a trapezoidal vertical cross-section instead of the male screw 375 at the tip end rod portion 370c of the shaft-like valve body member 300c.

The concave portion 282 is coaxially formed in the connecting shaft portion 280 from the extending end side thereof so as to have a trapezoidal concave shape in longitudinal section, and the concave portion 282 is formed in a tapered shape toward the inside of the connecting shaft portion 280. ing. The protruding portion 370d is formed in a trapezoidal longitudinal section so as to extend coaxially from the large-diameter shaft portion 374 of the shaft-like valve body member 300c toward the shaft-like connecting member 200c in a tapered shape. ing.

The shaft-shaped valve body member 300c constructed in this way is separably engaged with the concave portion 282 of the connecting shaft portion 280 at the projecting portion 370d. Other configurations are the same as those of the first embodiment.

In the fifth embodiment configured as described above, unlike the integral structure of the control valve in the first embodiment, the shaft-like valve body member 300c of the second diaphragm member 300 is the projecting portion. At 370d, it is adapted to releasably engage within the recess 282 of the shaft-like connecting member 200c of the first diaphragm member 200. As shown in FIG. This means that the first diaphragm 200a and the second diaphragm 300a, together with the shaft-like connecting member 200c and the shaft-like valve body member 300c, can It means that it is a separable structure as opposed to the integral structure described above.

Along with this, in a state in which the control valve controls the liquid discharged from the pump to flow out at a constant flow rate as in the first embodiment, the liquid pressure on the outflow side of the control valve When the load suddenly increases and the hydraulic pressure in the outflow cylinder 160 and the first liquid chamber Sb is suddenly increased, the hydraulic pressure toward the first pressure regulating chamber Sa with respect to the first diaphragm 200a is increased. .

Therefore, when the first diaphragm 200a bends toward the first pressure regulating chamber Sa, the first diaphragm 200a exerts a tensile force on the shaft-like connecting member 200c toward the first pressure regulating chamber Sa.

However, as described above, in the separable structure, the shaft-like connecting member 200c and the shaft-like valve body member 300c are separable from each other. As a result, the shaft-shaped valve body member 300c can be maintained at the same position. Therefore, there is no frictional engagement between the seat portion 373b and the annular valve seat portion 133a, which tends to occur when the tensile force described above also acts on the valve body portion 370b. This prevents the occurrence of particles from the valve seat portion 133a.

Based on such effects, the operation and effects of the control valve based on the first diaphragm member 200a and the second diaphragm member 300 described in the first embodiment can be achieved.

(Sixth embodiment)
FIG. 9 shows a sixth embodiment of a diaphragm control valve according to the present invention. In the sixth embodiment, in the configuration of the first diaphragm member 200, the annular body 200b is joined to the upper surface 140 of the diaphragm 200a by laser welding as in the third embodiment. The only difference is in points, and the rest of the configuration is the same as that of the fifth embodiment.

Therefore, in the sixth embodiment configured as described above, the operation and effects of the control valve based on the separable integral configuration described in the fifth embodiment can be similarly achieved.

In addition, in carrying out the present invention, the following various modifications can be given without being limited to the above embodiments.

(1) In carrying out the present invention, the diaphragm 200a described in the above embodiment is not limited to a diaphragm formed by forming into a film shape by extrusion molding of PFA, but is formed into a film shape by a compression molding method of PFA. It may be a diaphragm formed by compression molding.

The compression molding method is a method of filling PFA into a mold and compressing it into a film. It can be formed as a film-like diaphragm with excellent longevity and high smoothness, which can minimize the dust generation of particles of several nanometers in size. Also by this, the same effect as the above embodiment can be achieved.

(2) Further, in carrying out the present invention, the diaphragm member 200 may be grasped as a configuration that does not include the shaft-like connecting member 200c among the diaphragm 200a, the reinforcing annular body 200b, and the shaft-like connecting member 200c.

(3) Further, in carrying out the present invention, the reinforcing annular body 200b may be eliminated as necessary. In this case, the shaft-like connecting member 200c serves as a reinforcing member for the diaphragm 200a, so that the diaphragm 200a is positioned at its outer peripheral portion 210 inside the outer annular wall portion 122 of the peripheral wall 120 of the middle housing member 100b. On the peripheral side, it can be easily sandwiched between the inner annular wall portion 121 of the peripheral wall 120 of the middle housing member 100b and the inner annular wall portion 161 of the peripheral wall 160 of the upper housing member 100c.

(4) In carrying out the present invention, in the housing 100, the middle housing member 100b is provided with the middle wall 130 at an axially intermediate portion of the cylindrical circumferential wall consisting of the upper and lower side walls 150, 140, and the inner side of the cylindrical circumferential wall. may be comprehended as partition walls that form the storage chamber R on the side of the bottom housing member 100a and form the storage chamber S on the side of the upper housing member 100c.

(5) In carrying out the present invention, the material for forming the shaft-like connecting member 200c and the shaft-like valve body member 300c is not limited to PFA, and any fluorine resin may be used.

100... housing, 100a... bottom side housing member,
100b... middle side housing member, 100c... upper side housing member, 110... bottom wall,
130... Middle side wall, 131... Inflow side communication path, 132... Outflow side communication path,
133... Central communication passage, 133a... Annular valve seat portion, 120, 160... Peripheral wall,
140, 150... Cylindrical peripheral wall, 180... Upper wall, 160... Inflow tube, 170... Outflow tube,
200... Diaphragm member, 200a, 300a... Diaphragm,
200b, 300b... Reinforcement annular body, 200c... Axial connecting member,
210, 310... Peripheral portion 282... Concave portion 290... Plate-shaped auxiliary member,
300c... Axial valve member, 360... Circular substrate, 370... Rod,
370b...valve portion, 370d...protruding portion, Ra, Sa...pressure regulating chamber,
Rb, Sb... Liquid chambers.

Claims (6)

flow to the inflow sideEnter and flow out to the outflow sidehigh-purity chemicals and ultra-pureWaterIn a diaphragm control valve designed to control the flow rate of liquid,
A cylindrical peripheral wall, both opposing walls facing each other so as to block the cylindrical peripheral wall from its axial end openings, and the inside of the cylindrical peripheral wall and one opposing wall of the both opposing walls. a housing having a partition wall defining a first receiving chamber therebetween and defining a second receiving chamber between the other opposing wall;
a first diaphragm member accommodated in the first accommodation chamber and having a film-like first diaphragm made of PFA and a shaft-like connecting member made of fluororesin;
a second diaphragm member accommodated in the second accommodation chamber and having a film-like second diaphragm made of PFA and a shaft-like valve body member made of fluororesin;
In the first diaphragm member,
The first diaphragm has an outer peripheral portion that is located in the first storage chamber of the cylindrical peripheral wall.side circumferenceIt is supported in the axially intermediate portion of the wall portion, and the inside of the first storage chamber forms a first pressure regulating chamber on the one opposing wall side and a first liquid chamber on the dividing wall side. partitioned to form,
Of the two surfaces of the first diaphragm, the surface on the first pressure regulating chamber side is one side surface, and the surface on the first liquid chamber side is the other side surface. The shaft-like connecting member is attached at its base to the first diaphragmthe other aspect ofis joined by laser welding to the central portion of the first diaphragm on the side thereof, and extends from the central portion of the first diaphragm into the first liquid chamber,
In the second diaphragm member,
The second diaphragm has an outer peripheral portion that is located in the second storage chamber of the cylindrical peripheral wall.side circumferencesupported in the axially intermediate portion of the wallfrontThe inside of the second housing chamber is partitioned so that a second pressure regulating chamber is formed on the other opposing wall side and a second liquid chamber is formed on the partition wall side.,
Of the two surfaces of the second diaphragm, the surface on the second liquid chamber side is defined as one side surface, and the surface on the second pressure regulating chamber side is defined as the other side surface. The shaft-shaped valve body member is the second diaphragmsaid one aspect ofa base joined to the central portion of the second diaphragm by laser welding on the side, and the shaft-like connecting member passing from the base through a central communication passage formed in the central portion of the second liquid chamber and the partition wall. a rod coupled to the extending end of the
The partition wall is the second liquid chamber of the central communication passage.side openingThe hole has an annular valve seat portion facing the valve body portion of the shaft-shaped valve body member and forming a valve portion together with the valve body portion,
The cylindrical peripheral wall directs the liquid from the inflow side to theSecond liquidThe inflow path for inflow into the body chamber and the aboveSecond liquidan outflow passage for causing the liquid in the body chamber to flow out to the outflow side through the annular valve seat portion, the central communication passage, and the first liquid chamber;
In a state in which the first diaphragm receives a set pressure generated in the first pressure regulating chamber and the second diaphragm receives a set pressure generated in the second pressure regulating chamber, the first diaphragm and the second diaphragm are: The opening degree between the valve body portion and the annular valve seat portion is changed through the shaft-shaped connecting member and the shaft-shaped valve body member which are coupled to each other according to the fluctuation of the hydraulic pressure of the liquid on the inflow side. By controlling the opening to a constant degree, the liquid on the inflow side flows through the inflow passage, the second liquid chamber, the annular valve seat portion, and the central connection at a constant flow rate corresponding to the constant opening. A diaphragm type control valve characterized in that the liquid flows out to the outflow side through the passage, the first liquid chamber and the outflow path. flow to the inflow sideEnter and flow out to the outflow sidehigh-purity chemicals and ultra-pureWaterIn a diaphragm control valve designed to control the flow rate of liquid,
A cylindrical peripheral wall, both opposing walls facing each other so as to block the cylindrical peripheral wall from its axial end openings, and the inside of the cylindrical peripheral wall and one opposing wall of the both opposing walls. a housing having a partition wall defining a first receiving chamber therebetween and defining a second receiving chamber between the other opposing wall;
a first diaphragm member accommodated in the first accommodation chamber and having a film-like first diaphragm made of PFA and a shaft-like connecting member made of fluororesin;
a second diaphragm member accommodated in the second accommodation chamber and having a film-like second diaphragm made of PFA and a shaft-like valve body member made of fluororesin;
In the first diaphragm member,
The first diaphragm has an outer peripheral portion that is located in the first storage chamber of the cylindrical peripheral wall.side circumferenceIt is supported in the axially intermediate portion of the wall portion, and the inside of the first storage chamber forms a first pressure regulating chamber on the one opposing wall side and a first liquid chamber on the dividing wall side. partitioned to form,
Of the two surfaces of the first diaphragm, the surface on the first pressure regulating chamber side is one side surface, and the surface on the first liquid chamber side is the other side surface. The shaft-like connecting member is attached at its base to the first diaphragmthe other aspect ofis joined by laser welding to the central portion of the first diaphragm on the side thereof, and extends from the central portion of the first diaphragm into the first liquid chamber,
In the second diaphragm member,
The second diaphragm has an outer peripheral portion that is located in the second storage chamber of the cylindrical peripheral wall.side circumferencesupported in the axially intermediate portion of the wallfrontThe inside of the second housing chamber is partitioned so that a second pressure regulating chamber is formed on the other opposing wall side and a second liquid chamber is formed on the partition wall side.,
Of the two surfaces of the second diaphragm, the surface on the second liquid chamber side is defined as one side surface, and the surface on the second pressure regulating chamber side is defined as the other side surface. The shaft-shaped valve body member is the second diaphragmsaid one aspect ofa base joined to the central portion of the second diaphragm by laser welding on the side, and the shaft-like connecting member passing from the base through a central communication passage formed in the central portion of the second liquid chamber and the partition wall. a rod separably connected to the extending end of the
The partition wall is the second liquid chamber of the central communication passage.side openingThe hole has an annular valve seat portion facing the valve body portion of the shaft-shaped valve body member and forming a valve portion together with the valve body portion,
The cylindrical peripheral wall directs the liquid from the inflow side to theSecond liquidThe inflow path for inflow into the body chamber and the aboveSecond liquidan outflow passage for causing the liquid in the body chamber to flow out to the outflow side through the annular valve seat portion, the central communication passage, and the first liquid chamber;
In a state in which the first diaphragm receives a set pressure generated in the first pressure regulating chamber and the second diaphragm receives a set pressure generated in the second pressure regulating chamber, the first diaphragm and the second diaphragm are: The valve body portion is connected to the annular valve seat portion via the shaft-like connecting member and the shaft-like valve body member that are separably connected to each other according to fluctuations in the hydraulic pressure of the liquid on the inflow side. By controlling the degree of opening to a constant degree of opening, the liquid on the inflow side flows through the inflow passage, the second liquid chamber, the annular valve seat portion, and the like at a constant flow rate corresponding to the constant degree of opening. A diaphragm type control valve characterized in that the liquid flows out to the outflow side through the central communication passage, the first liquid chamber and the outflow passage. 3. The first diaphragm member is provided with a fluororesin reinforcing annular body that is laser-welded to the other side surface or the one side surface of the first diaphragm so as to follow the outer peripheral portion thereof. 3. The diaphragm control valve according to 1 or 2. The first diaphragm member is coaxially joined to the first diaphragm by laser welding from the one side surface thereof so as to suppress the deflection of the first diaphragm and restrict the movable region of the first diaphragm. The diaphragm control valve according to any one of claims 1 to 3, further comprising a plate-shaped auxiliary member formed by The diaphragm type according to any one of claims 1 to 4, wherein the first diaphragm is formed into a film by extrusion molding or compression molding PFA together with the second diaphragm. control valve. 6. The diaphragm control valve according to claim 5, wherein the first diaphragm and the second diaphragm have a thickness within a range of 0.1 (mm) or more and 0.6 (mm) or less. .

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