JP2020056466A - Diaphragm type control valve - Google Patents

Abstract

To provide a control valve using a diaphragm member configured to have a diaphragm structure in which laser welding is applied to connection of a valve element and a central part of a diaphragm even when the diaphragm is thin like a film.SOLUTION: In a control valve, a first diaphragm member 200 includes: a film-like diaphragm 200a comprising PFA; and a rod-like connection member 200c joined to a central part 220 of the diaphragm 200a from the lower surface side by laser welding. A second diaphragm member 300 includes: a film-like diaphragm 300a comprising PFA; and a rod-like valve element member 300c joined to a central part 320 of the diaphragm 300a from the upper surface side by laser welding. The rod-like valve element member 300c is separably coupled to the rod-like connection member 200c.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a diaphragm-type control valve suitable for use in flowing a liquid such as a high-purity chemical solution or ultrapure water in a semiconductor manufacturing apparatus.

  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 upper housing member. A housing in which a first housing chamber is formed between the housing member and the other housing chamber between the middle housing member and the bottom housing member; and a first pressure regulation chamber on the upper housing member side. A first diaphragm that forms and defines 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 regulation chamber is formed on the bottom housing member side and the middle side. A second diaphragm that partitions the inside of the other-side storage chamber so as to form a second liquid chamber on the housing side, and is provided from the center of the first liquid chamber to the center of the second liquid chamber. An axial connecting member extending from the central portion of the first diaphragm into the central communication passage, and an axial valve member extending from the central portion of the second diaphragm into the central communicating passage and connected to the axial connecting member; It has.

  In the control valve thus configured, 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 reduced to the second pressure. The setting is such that the pressure acting on the one diaphragm opposes the set pressure acting from the first pressure regulation chamber side, and the liquid pressure of the liquid flowing into the second liquid chamber acts on the second diaphragm from the second pressure regulation chamber side. Acts against pressure.

  Along with this, the first diaphragm, the second diaphragm, and the structure including the shaft-shaped connecting member and the shaft-shaped valve body member which are connected or separably connected to each other, act in opposition to each other via the first diaphragm. The central link is displaced in accordance with the set pressure in the pressure chamber, the liquid pressure in the first liquid chamber, and the set pressure in the second pressure chamber and the liquid pressure in the second liquid chamber that are opposed to each other via the second diaphragm. An annular valve seat provided at the end of the opening of the passage on the first liquid chamber side and a valve body provided on the axial valve body member from the second liquid chamber side to face the annular valve seat; Control the interval to a fixed interval.

  This means that the control valve applies the liquid flowing from the inflow side to the valve body of the axial valve body member with the displacement of the component according to the flow rate of the liquid under both set pressures. This means that control is performed so as to flow out to the outflow side at a fixed flow rate corresponding to a fixed interval between the central communication passage and the annular valve seat.

  When a control valve having such a configuration is used in a semiconductor manufacturing apparatus, in a cleaning step or a stripping step in the semiconductor manufacturing apparatus, a high-purity chemical liquid composed of a highly corrosive chemical such as a strong acid or a strong alkali is used as the liquid described above. Therefore, as a material for forming the diaphragm in the control valve, it is desirable to use a fluororesin having excellent chemical resistance such as acid resistance and alkali resistance.

  Further, in a semiconductor manufacturing apparatus, since elution of a metal component or an organic component from a control valve is not allowed, it is preferable to use a fluororesin having a low elution property as a material for forming the diaphragm.

  Further, due to the configuration of the control valve as described above, it is desirable to employ a fluororesin which has excellent flexibility and can maintain a long life.

  In view of the above, it is required that a fluororesin having chemical resistance, low elution properties, excellent flexibility and long life can be used as a material for forming the diaphragm.

Japanese Patent No. 5286330

  By the way, in the control valve having the above-described configuration, since the contamination of the liquid by the particles from the control valve in the semiconductor manufacturing apparatus is not allowed, the liquid flowing through the flow path system in the control valve is subjected to diaphragm, It is necessary to be isolated from one of the chambers, and for that purpose, it is required that the diaphragm is integrally formed with an outer peripheral portion, a curved displacement portion, and a central portion.

  Here, when PTFE is employed as a material for forming the diaphragm, PTFE cannot form a diaphragm of good quality by injection molding or extrusion molding because the melt flow rate is low. Therefore, the diaphragm is formed by cutting a compression molded round bar of PTFE.

  Although the life of a PTFE diaphragm formed by cutting in this way is long, in a control valve using such a diaphragm, a curved displacement portion formed by cutting extends or extends on the surface due to its operation. 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 when the wiring pitch of a silicon wafer manufactured by a semiconductor manufacturing apparatus is larger than 10 (nm), for example.

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

  The life of the PFA diaphragm formed by the cutting process is short. In addition, the control valve using the PFA diaphragm formed by the cutting process in this way, the operation of the PTFE diaphragm formed by the cutting process on the surface of the curved displacement portion formed by the cutting process. As in the case of the bending displacement portion, the dust is generated from the bending displacement portion, though slightly, because it is extended or compressed.

  Here, when PFA is adopted as a material for forming the diaphragm, and the PFA is used to form a diaphragm having a large bending displacement portion by injection molding and cutting to form a diaphragm, injection molding or compression molding is used. When formed into a flesh shape, crystallization in the curved displacement portion does not occur uniformly, the interface becomes a starting point of destruction and the life is shortened, so diaphragms having such a curved displacement portion are hardly adopted. .

  On the other hand, in recent years, further miniaturization has been demanded in the production of semiconductor elements, for example, silicon wafers by a semiconductor production apparatus. For example, there is a demand that the wiring pitch in a silicon wafer be reduced to 10 (nm) or less. Therefore, the generation of dust from the control valve is not allowed even for the generation of particles of several nm in size.

  However, as described above, a control valve using a diaphragm formed by cutting causes distraction or compression on the surface of the curved displacement portion formed by the cutting process along with its operation, and accordingly, from the curved displacement portion, It generates dust, albeit tiny.

  In such a case, it is impossible to cope with a situation in which even the generation of particles of several nm in size from the control valve is not allowed, and further improvement is required for a diaphragm having a curved displacement portion formed by cutting. Requested.

  On the other hand, since the PFA film is thin, the crystallization can be uniformized. Therefore, the PFA film is formed by extrusion or compression molding, and at least as a curved displacement portion of the diaphragm. Adopting this leads to the improvement of the diaphragm described above.

  By the way, in the above-mentioned control valve, the first diaphragm is connected to the shaft-like connecting member at the center. However, when the film-like and very thin diaphragm is employed as the first diaphragm of the control valve as described above, a connecting portion required for connecting to the shaft-like connecting member is formed at the center of the diaphragm. I can't. This means that it is extremely difficult to connect the central portion of the film-shaped first diaphragm to the shaft-shaped connecting member without the connecting portion.

  In response to this, it is conceivable to use a configuration of a diaphragm valve to which laser welding according to the resin diaphragm sealing method described in Patent Document 1 is applied.

  In the diaphragm valve described in Patent Document 1, for the purpose of sealing, the diaphragm is laser-welded at its flange portion to the flange portion of the lower housing so as to seal the valve body chamber. Focusing on such a thing, it came to the idea that it would be possible to use laser welding for connecting the central part of the film-shaped diaphragm made of PFA and the shaft-shaped connecting member.

  In order to cope with the above, the present invention provides a film-like PFA capable of securing flexibility and long life, and forming a diaphragm capable of minimizing dust generation of about several nm. The material is selected, and an appropriate fluororesin axial connection member is used in consideration of the ease of connection with the center of the diaphragm, and even if the diaphragm is thin as a film, the valve body and the diaphragm An object of the present invention is to provide a control valve using a diaphragm member configured as a diaphragm structure in which laser welding is applied to a connection with a central portion.

In order to solve the above-mentioned problems, a diaphragm control valve according to the present invention has the following features.
The flow rate of a liquid such as a high-purity chemical or ultrapure water flowing into the inflow side is controlled in accordance with the fluctuation of the liquid pressure.

In the control valve,
The cylindrical peripheral wall (140, 150), the opposing walls (110, 180) opposing each other so as to close the cylindrical peripheral wall from both axial openings, and the interior of the cylindrical peripheral wall are opposed to each other. A partition is formed so as to form a first storage chamber (S) with one opposing wall (180) of the wall and to form a second storage chamber (R) with the other opposing wall (110). A housing (100) having a partition wall (130) that defines
A first diaphragm member (200) housed in the first housing chamber and having a film-shaped first diaphragm (200a) made of PFA and a shaft-like connecting member (200c) made of fluororesin;
A second diaphragm member (300) having a PFA film-shaped second diaphragm (300a) and a fluororesin-made axial valve member (300c) housed in the second housing chamber;
In the first diaphragm member,
The first diaphragm is supported at an outer peripheral portion (210) of the cylindrical peripheral wall in an axially intermediate portion of the peripheral wall portion on the first storage chamber side, and divides the inside of the first storage chamber into one of the opposed portions. A first pressure regulation chamber (Sa) is formed on the wall side and a first liquid chamber (Sb) is formed on the partition wall side;
The shaft-like connecting member is joined at its base to the central portion of the first diaphragm on the lower surface side of the first diaphragm by laser welding, and extends from the central portion of the first diaphragm into the first liquid chamber. And
In the second diaphragm member,
The second diaphragm is supported at an outer peripheral portion (310) of the cylindrical peripheral wall in an axially intermediate portion of the peripheral wall portion on the second storage chamber side. The interior of the second storage chamber is partitioned such that a second pressure regulation chamber (Ra) is formed on the other opposing wall side and a second liquid chamber (Rb) is formed on the partition wall side,
The shaft-shaped valve member is formed on the upper surface side of the second diaphragm at the center of the second diaphragm by laser welding, and formed at the center of the second liquid chamber and the partition wall from the base. A rod (370) coupled to the extended end of the shaft-like connecting member through a central communication passage (133) formed by
The partition wall faces the valve body (370b) of the shaft-shaped valve body member at the second liquid chamber side opening of the central communication passage, and forms an annular valve seat with the valve body. (133a),
The cylindrical peripheral wall passes through the inflow passages (160, 131) through which the liquid flows from the inflow side into the first liquid chamber and the liquid in the first liquid chamber through the annular valve seat, the central communication path, and the first liquid chamber. An outflow path (132, 170) for outflow to the outflow side is provided,
In a state where the first diaphragm receives the set pressure generated in the first pressure regulating chamber and the second diaphragm receives the setting generated in the second pressure regulating chamber, the first diaphragm and the second diaphragm form the liquid of the inflow side liquid. By controlling the opening of the valve body with the annular valve seat to a constant opening through a shaft-shaped connecting member and a shaft-shaped valve body member that are connected to each other in accordance with a change in pressure. The liquid on the inflow side flows through the inflow path, the second liquid chamber, the annular valve seat, the central communication path, the first liquid chamber, and the outflow path at a constant flow rate corresponding to the constant opening degree. It is characterized by flowing out to the outflow side.

  According to this, in the control valve, the first diaphragm, the shaft-like connecting member connected to each other, and the integral structure consisting of the shaft-like valve body member and the second diaphragm inflow under both set pressures. In accordance with the fluctuation of the liquid pressure of the liquid flowing from the side, the opening of the valve body with respect to the annular valve seat is displaced so as to have a constant opening, and the flow of the liquid is controlled to be constant. .

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

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

  Further, a second diaphragm member is formed of a second diaphragm made of PFA and a shaft member made of fluororesin which is coaxially joined to a central portion of the second diaphragm by laser welding and extends from the central portion. It is composed of both.

  According to this, since the connection between the central portion of the second diaphragm and the axial valve member is performed by laser welding, the axial valve member and the central portion of the second diaphragm can be satisfactorily connected.

  Further, the first diaphragm is formed as a film-shaped diaphragm by PFA together with the second diaphragm. Therefore, the first diaphragm and the second diaphragm can be formed as a diaphragm having excellent flexibility and long life and capable of suppressing dust generation to a minimum (minimum), even in the form of a film.

  Further, although the above-mentioned film-shaped first diaphragm is very thin, the first diaphragm is joined to the shaft-like connecting member by laser welding at the center thereof, so that the first diaphragm is pivoted at the center thereof. The shaft-shaped connecting member can be easily connected to the central portion of the diaphragm by laser welding without having a connecting portion required for connecting to the shaped connecting member.

  According to the second aspect of the present invention, the diaphragm control valve according to the present invention is different from the first embodiment in that the first diaphragm receives a set pressure generated in the first pressure regulating chamber. In a state where the second diaphragm receives the set pressure generated in the second pressure regulation chamber, the first diaphragm and the second diaphragm are connected to each other in a separable manner in accordance with the fluctuation of the liquid pressure of the liquid on the inflow side. By controlling the opening of the valve body with the annular valve seat to a constant opening via the shaft-like connecting member and the shaft-like valve member, a constant flow rate corresponding to the constant opening. The difference is that the liquid on the inflow side flows out to the outflow side through the inflow path, the second liquid chamber, the annular valve seat, the central communication path, the first liquid chamber, and the outflow path.

  According to this, unlike the invention according to the first aspect, the control valve can be separated by the first diaphragm, the shaft-shaped connecting member and the shaft-shaped valve body member and the second diaphragm that are separably connected to each other. Even when the component is configured, the control valve is operated under the two set pressures, with the displacement of the separable component corresponding to the fluctuation of the liquid pressure of the liquid flowing from the inflow side, the annular valve of the valve body portion. The opening to the seat is controlled to a constant opening, in other words, the flow rate of the liquid from the inflow side is controlled to a constant flow rate. Other functions and effects are the same as those of the first aspect.

According to a third aspect of the present invention, in the diaphragm control valve according to the first or second aspect,
The first diaphragm member is provided with a fluororesin reinforcing ring (200b) joined to the lower surface or the upper surface of the first diaphragm by laser welding along the outer peripheral portion.

  According to this, even if it is difficult to handle the first diaphragm because it is thin like a film, the reinforcing annular member can be formed by the above-described joining configuration of the outer peripheral portion of the first diaphragm and the reinforcing annular member by laser welding. However, the reinforcing function can be satisfactorily exerted on the first diaphragm. Therefore, in addition to the function and effect of the invention described in claim 1, the function and effect that the diaphragm can be easily handled without bending even if the diaphragm is thin can be achieved.

According to a fourth aspect of the present invention, in the diaphragm control valve according to any one of the first to third aspects,
The first diaphragm member is a plate-shaped member which is coaxially joined to the first diaphragm by laser welding from the upper surface side of the first diaphragm so as to suppress the bending of the first diaphragm and regulate the movable range of the first diaphragm. An auxiliary member (290) is provided.

  According to this, the auxiliary member is coaxially joined to the first diaphragm from the upper surface side by laser welding on the lower surface thereof. Thus, the first diaphragm can be favorably displaced without bending. Thereby, the invention described in any one of claims 1 to 3 can be achieved even better.

According to a fifth aspect of the present invention, in the diaphragm control valve according to any one of the first to fourth aspects,
The first diaphragm is formed in a film shape by extruding or compressing PFA together with the second diaphragm.

  According to this, the first diaphragm and the second diaphragm are formed into a film shape by extruding or compressing PFA to form the first diaphragm and the second diaphragm by cutting. In particular, the first and second diaphragms have a surface with a high degree of smoothness that can minimize (minimize) even the generation of particles such as particles having a size of several nanometers. The first diaphragm and the second diaphragm having excellent chemical resistance, low elution, flexibility and long life can be formed.

  In addition, as described above, the first diaphragm and the second diaphragm are formed into a film shape by extruding or compressing PFA, so that the first diaphragm and the second diaphragm center around the curved displacement portion. The crystallization can be uniform, and the life of the first diaphragm and the second diaphragm can be further extended. As described above, the operation and effect of the invention according to any one of claims 1 to 4 can be further improved.

According to a sixth aspect of the present invention, in the diaphragm control valve according to the fifth aspect,
The first diaphragm, together with the second diaphragm, has a thickness in the range of 0.1 (mm) or more and 0.6 (mm) or less.

  Thereby, the operation and effect of the invention described in claim 5 can be more reliably achieved. Here, the reason why the thickness of the first diaphragm or 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. is there. Further, the reason why the thickness is set to 0.6 (mm) or less is that if the first diaphragm and the second diaphragm are thicker than 0.6 (mm), the bending displacement portions of the first diaphragm and the second diaphragm are too hard and sensitive. This is because the first diaphragm and the second diaphragm are liable to be broken, and the first diaphragm and the second diaphragm are liable to be broken.

  In addition, the code | symbol in parenthesis of each said means shows the correspondence with the concrete means described in embodiment mentioned later.

It is a longitudinal section showing a 1st embodiment of a diaphragm type control valve concerning the present invention. It is sectional drawing of the 1st diaphragm member in the said 1st Embodiment. It is sectional drawing of the 2nd diaphragm member in the said 1st Embodiment. It is a sectional view showing an important section of a 2nd embodiment of a diaphragm type control valve concerning the present invention. It is a longitudinal section showing a 3rd embodiment of a diaphragm type control valve concerning the present invention. It is sectional drawing of the 1st diaphragm member in the said 3rd Embodiment. It is sectional drawing which shows the principal part of 4th Embodiment of the diaphragm type control valve which concerns on this invention. It is a longitudinal section showing a 5th embodiment of a diaphragm type control valve concerning the present invention. It is a longitudinal section showing a 6th embodiment of a diaphragm type control valve concerning the present invention.

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

(1st 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 for manufacturing a semiconductor element. The semiconductor manufacturing apparatus manufactures a semiconductor wafer and a semiconductor element using the semiconductor wafer using a liquid supplied from a liquid supply source (not shown) to a piping path via a pump (not shown). 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 solution or ultrapure water, and is required to be clean due to the characteristics of the semiconductor manufacturing apparatus.

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

  As shown in FIG. 1, the control valve is configured to include a cylindrical housing 100 and a first diaphragm member 200 and a second diaphragm member 300 assembled in the cylindrical housing 100.

  The cylindrical housing 100 includes a bottom housing member 100a, a middle housing member 100b, and an upper housing member 100c.

  The bottom housing member 100a includes a bottom wall 110 and a peripheral wall 120, and 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 is formed inside 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 from the center opening of the upper surface to the left side in FIG. The exhaust hole portion 112 is formed in the bottom wall 110 so as to penetrate 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 111 is configured to supply 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) to the second pressure regulation chamber Ra (described later). ), While the exhaust hole portion 112 serves to exhaust the compressed air flow supplied into the second pressure regulation chamber Ra to the outside.

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

  As shown in FIG. 1, the middle housing member 100b is coaxially assembled to the bottom housing member 100a from above, and the middle housing member 100b includes a middle wall 130, a lower peripheral wall 140, and an upper peripheral wall. 150, an inflow cylinder 160, and an outflow cylinder 170.

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

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

  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 formed by an opening wall 140a of the peripheral wall 120 of the bottom housing member 100a. It is assembled coaxially with the part 120a. Specifically, the opening wall 140a of the lower peripheral wall 140 has an inner annular wall 141 and an outer annular wall 142, and the inner annular wall 141 protrudes downward from the outer annular wall 142. As shown in the figure, the inner peripheral wall portion of the opening wall portion 140a is formed in a ring shape facing the inner annular wall portion 121 of the peripheral wall 120. The outer annular wall 142 is formed in an annular shape at an outer peripheral portion of the opening wall 140a so as to face the outer annular wall 122 of the peripheral wall 120.

  Thus, the lower peripheral wall 140 is coaxially fitted at the inner annular wall 141 into the outer annular wall 122 of the peripheral wall 120, and is disposed inside the peripheral wall 120 via the outer peripheral portion of the second diaphragm member 300. The lower peripheral wall 140 is assembled to the peripheral wall 120 by engaging with the annular wall 121 and engaging with the outer annular wall 122 of the peripheral wall 120 at the outer annular wall 142. Thus, the lower peripheral wall 140 and the peripheral wall 120 form a housing chamber R (hereinafter, also referred to as a second housing chamber R) that houses the second diaphragm 300 inside each of the lower peripheral wall 140 and the peripheral wall 120.

  The inflow tube 160 extends from the outer end opening of the inflow-side communication passage 131 to the outside of the middle wall 130, and the inflow tube 160 communicates the inflow-side communication passage 131 to the upstream side of the piping path. Play a role. The outflow tube 170 extends outward from an outer end opening of the outflow side communication passage 132, and the outflow tube 170 plays a role of communicating the outflow side communication passage 132 with the downstream side of the piping route. .

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

  The upper housing member 100c includes an upper wall 180 and a peripheral wall 190. The upper wall 180 is formed in the shape of a rectangular plate having a horizontal cross section. The upper wall 180 is formed with an air supply hole 181 and an exhaust hole 182 as shown in FIG.

  In the first embodiment, the air supply hole 181 is configured to supply 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) to the first pressure regulation chamber Sa (described later). ), While the exhaust holes 182 serve to exhaust the compressed air flow supplied into the first pressure regulation chamber Sa to the outside.

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

  The inner annular wall portion 191 is formed at an inner peripheral side portion of the opening wall portion 190a so as to annularly protrude below the outer annular wall portion 192, and the inner annular wall portion 191 is formed of a first diaphragm. The outer peripheral portion of the member 200 is opposed to the inner annular wall portion 151 of the upper peripheral wall 150. On the other hand, the outer annular wall portion 192 is formed to protrude downward at an outer peripheral portion of the opening wall portion 190a so as to face the outer annular wall portion 152 of the upper peripheral wall 150.

  Thus, the upper housing member 100c is assembled to the middle housing member 100b at the opening wall 190a of the peripheral wall 190 via the first diaphragm member 200 so as to engage with the opening wall 150a of the upper peripheral wall 150. Have been. Here, the upper housing member 100 c is formed on the outer annular wall 191 of the peripheral wall 190 so as to face the inner annular wall 151 of the upper peripheral wall 150 via the outer peripheral portion of the first diaphragm member 200. The wall 192 engages with the outer annular wall 152 of the upper peripheral wall 150 to be assembled to the middle housing member 100b. As a result, the upper housing member 100c, together with the middle housing member 100b, is provided inside each of the upper peripheral wall 150 and the peripheral wall 190 in the accommodation room S (hereinafter, also referred to as the first accommodation room S) that accommodates the first diaphragm member 200. Is configured.

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

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

  As a result, the first diaphragm 200a is located inside the first storage chamber S at the central portion 220 and the bending displacement portion 230, and on the upper wall 180 side, the pressure regulation chamber Sa (hereinafter, referred to as the first pressure regulation chamber). The inside of the first storage chamber S is defined so as to form a liquid chamber Sb (hereinafter, also referred to as a first liquid chamber Sb) on the side of the middle wall 130 while forming a chamber Sa. Accordingly, the first pressure regulation chamber Sa is maintained at the set pressure based on the compressed air flow supplied from the first compressed air flow supply source through the air supply hole 181 at a constant pressure. It is supposed 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. Thus, the liquid generates a liquid pressure acting on the lower surface 250 of the first diaphragm 200a in the first liquid chamber Sb.

  The first diaphragm 200a is formed by extrusion molding with a tetrafluoroethylene / perfluoroalkylvinyl ether copolymer (PFA) so as to integrally include 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.

  In the first embodiment, the grounds for using PFA as a material for forming the first diaphragm 200a will be described.

  Since the first diaphragm 200a is in contact with a highly pure chemical such as a highly corrosive chemical such as a strong acid or a strong alkali among the liquids flowing through the piping path, the first diaphragm 200a is configured as a control valve. It is desirable to have excellent chemical resistance such as acid resistance and alkali resistance.

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

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

  Therefore, in the first embodiment, PFA is used as a material for forming the first diaphragm 200a because PFA is excellent in chemical resistance, low elution property, heat resistance and corrosion resistance, and can ensure flexibility and long life. Has been adopted. In the first embodiment, PFA is also used as a material for forming the cylindrical housing 100.

  Further, the first diaphragm 200a is formed as a film-shaped diaphragm with PFA so as to have a thickness within a predetermined thickness range, for example, 0.5 (mm). 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. Further, the reason why the thickness is set to 0.6 (mm) or less is that if the first diaphragm 200a is thicker than 0.6 (mm), the curved displacement portion of the first diaphragm 200a is too hard to be sensitively displaced. At the same time, the first diaphragm 200a is liable to be broken such as a crack.

  In addition, as described above, in forming the first diaphragm 200a, the extrusion molding method using PFA is adopted based on the following grounds.

  For example, when a diaphragm is formed by cutting a material made of PFA, a cutting mark is formed on the surface of the diaphragm. Therefore, when the diaphragm formed by such a cutting process comes into contact with the liquid flowing in the first liquid chamber Sb of the control valve, particles, for example, minute particles having a size of several nanometers, due to the cut marks of the diaphragm, are very small. However, if the particles are peeled off from the diaphragm and become mixed with the liquid, the liquid cannot be kept clean. As a result, when the liquid is refluxed 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 a product manufactured by the semiconductor manufacturing apparatus, for example, a silicon wafer having a wiring pitch of 10 (nm) or less. For this reason, it is necessary to reliably prevent particles from being mixed into the liquid in the control valve, for example, even particles having a size of several nm from the liquid.

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

  Therefore, in the first embodiment, the first diaphragm 200a is formed into a film shape by the extrusion molding method of PFA. Thereby, the film-shaped diaphragm extruded by the extruder is formed of a particle having a size of several nm formed to have a very good smooth surface on each surface, that is, a so-called smooth surface. It is a diaphragm capable of minimizing dust generation, and can be formed as a long-life diaphragm excellent in chemical resistance, low elution, and flexibility.

  The reinforcing annular body 200b is for reinforcing the film-like diaphragm 200a. The reinforcing annular body 200b is joined along the outer peripheral portion 210 of the diaphragm 200a by laser welding from the lower surface 250 side of the diaphragm 200a. I have. Thus, the reinforcing annular body 200b is formed integrally with the outer peripheral portion 210 of the diaphragm 200a, and is located below the outer peripheral portion 210, and together with the outer peripheral portion 210, the upper peripheral wall of the middle housing member 100b. By being fitted on the inner peripheral side of the outer annular wall portion 152 of the upper housing member 150, 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 are sandwiched. I have.

  In this case, even if it is difficult to handle the first diaphragm 200a because it is thin, the reinforcing annular body 200b is formed by the above-described joining configuration of the outer peripheral portion 210 of the first diaphragm 200a and the reinforcing annular body 200b by laser welding. The first diaphragm 200a easily exerts a reinforcing function from the outer peripheral portion 210 side of the first diaphragm 200a so that the first diaphragm 200a can be easily mounted 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 fitted. Accordingly, the first diaphragm 200a can satisfactorily engage with the reinforcing annular body 200b on the inner annular wall 151 and be sandwiched as described above.

  In the first embodiment, the reinforcing annular body 200b is formed by injection molding into a column shape using PFA and then cutting into an annular shape. Here, the reinforcing annular body 200b has an outer diameter equal to the outer diameter of the first diaphragm 200a, and the axial width and thickness of the reinforcing annular body 200b are the same as those of the film-shaped first diaphragm 200a. Each value is set to a value suitable for reinforcement and easy handling.

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

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

  The truncated conical portion 270 extends from the center of the disc-shaped base 260 in a tapered manner so as to be coaxially opposed to the axial valve body member 300c. The connecting shaft 280 extends axially from the center of the extending end 271 of the truncated cone 270 so as to coaxially face the axial valve body member 300c. , A female screw hole 281 is formed. In the first embodiment, the female screw hole 281 is formed coaxially in the connecting shaft 280 from the extended end thereof. The shaft-like connecting member 200c thus configured is integrated with the diaphragm 200a and the reinforcing annular body 200b to form the first diaphragm member 200.

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

  Thus, the second diaphragm 300a, along with the reinforcing annular body 300b, on the outer peripheral portion 310 thereof is formed 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. In a state in which the reinforcing annular body 300b is positioned on the upper side, the engagement is performed on the inner annular wall portion 121 of the opening wall portion 120a of the peripheral wall 120, and the opening portion 140a of the lower peripheral wall 140 is engaged. It is sandwiched between the inner annular wall 141 and the inner annular wall 121 of the opening wall 120 a of the peripheral wall 120.

  As a result, the second diaphragm 300a is located inside the second storage chamber R at the central portion 320 and the bending displacement portion 330, and is located on the bottom wall 110 side in the pressure regulating chamber Ra (hereinafter, referred to as a second pressure regulating chamber). The inside of the second storage chamber R is formed so as to form a liquid chamber Rb (hereinafter, also referred to as a second liquid chamber Rb) on the middle wall 130 side while forming a chamber Ra. Accordingly, the second pressure regulation chamber Ra is based on a 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.

  Further, the second liquid chamber Rb can communicate with the first liquid chamber Sb via the central communication passage 133 of the middle wall 130 and the annular valve seat 133a. Along with this, the liquid in the second liquid chamber Rb passes through the central communication passage 133 from between the seating portion 373a (to be described later) of the valve body portion 370b of the axial valve body member 300c and the annular valve seat portion 133a. It is possible to flow into the first liquid chamber Sb.

  Accordingly, the liquid generates a liquid pressure acting on the upper surface 340 of the diaphragm 300a in the second liquid chamber Rb, and is also generated from between the seating portion 373a and the annular valve seat portion 133a of the axial valve body member 300c. The liquid flows out through the central communication path 133, the first liquid chamber Sb, the outflow-side communication path 132, and the outflow cylinder 170 to the downstream side of the pipe path. Here, based on the same grounds as in the case of the above-described first diaphragm 200a, the second diaphragm 300a is formed into a film by extrusion molding of PFA with the same configuration as that of the first diaphragm 200a.

  The reinforcing annular body 300b is for reinforcing the film-shaped second diaphragm 300a from the 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.

  Accordingly, the reinforcing annular body 300b is formed integrally with the outer peripheral portion 310 of the second diaphragm 300a, and is located above the outer peripheral portion 310, and together with the outer peripheral portion 310, the bottom housing member 100a is formed. It is fitted on the inner peripheral side of the outer annular wall 122 of the peripheral wall 120. Here, the reinforcing annular body 300b plays a role of satisfactorily reinforcing the second diaphragm 300a from the outer peripheral side. Therefore, even if the second diaphragm 300a is thin and is difficult to handle, the second diaphragm 300a, together with the reinforcing annular body 300b, has the same function as that of the bottom housing member 100a under the reinforcing function of the above-described reinforcing annular body 300b. It can be easily fitted on 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, at the outer peripheral portion 310, the inner annular wall portion 141 of the lower peripheral wall 140 and the peripheral wall of the bottom housing member 100a. 120 between the inner annular wall portion 121. In the first embodiment, the radial width of the reinforcing annular body 300b is set to be wider than the radial width of the above-described reinforcing annular body 200b. Further, the reinforcing annular body 300b is formed of PFA similarly to the reinforcing annular body 200b.

  As shown in FIG. 3, the axial valve body member 300c includes a circular substrate 360 and a rod 370. In the first embodiment, the axial valve body member 300c is formed 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 axial valve body member 300c is joined to the central portion 320 of the second diaphragm 300a by laser welding on the circular substrate 360 as described above. The circular substrate 360 serves to reinforce the second diaphragm 300a from the central portion 320 side with the circular substrate 360. Thereby, as described above, the second diaphragm 300a can be fitted on the inner peripheral side of the outer annular wall portion 122 of the peripheral wall 120 of the bottom housing member 100a by the axial valve body member 300c on the circular substrate 360. Therefore, it can be more easily achieved in combination with the reinforcing annular body 3200b.

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

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

  Thus, the valve body portion 370b has a base end portion 373a (hereinafter, also referred to as a seating portion 373a) extending from the cylindrical portion 371 of the upper truncated cone portion 373 and an annular valve seat portion 133a (described later). Together, they constitute a valve. Accordingly, the valve portion is closed by the seating portion 373a of the upper truncated cone portion 373 being seated on the annular valve seat portion 133a. This means that the control valve closes. Further, the valve portion is opened by separating the seat portion 373a of the upper truncated cone portion 373 from the annular valve seat portion 133a. This means that the control valve opens. Here, the lower opening end 133a of the central communication passage 133 of the middle wall 130 is formed as an annular valve seat 133a.

  The distal rod portion 370c is integrally formed with a large-diameter shaft portion 374 and a male screw portion 375, and the large-diameter shaft portion 374 is a tapered end of the upper truncated cone 373 of the valve body 370b. Coaxially extending upward from The male screw portion 375 extends coaxially from the center of the large-diameter shaft portion 374 toward the shaft-shaped connecting member 200c. The male screw portion 375 is connected to the connecting shaft portion 280 of the shaft-shaped connecting member 200c. It is coaxially fastened in the female screw hole 281. Accordingly, the large-diameter shaft portion 374 engages with the outer peripheral portion of the connection shaft portion 280 at the outer peripheral portion. Thus, the shaft-shaped valve member 300c is integrally connected or connected to the shaft-shaped connection member 200c.

  In the first embodiment configured as described above, when a semiconductor element is manufactured by the semiconductor manufacturing apparatus, the 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 a first set pressure) is generated in the first pressure regulation chamber Sa. On the other hand, when the compressed air flow is supplied from the second compressed air flow supply source into the second pressure regulating chamber Ra through the communication path 111 of the bottom housing member 100a at the constant pressure, the set pressure ( Hereinafter, also referred to as a second set pressure) is generated in the second pressure regulation chamber Ra.

  Here, the axial valve body member 300c of the second diaphragm member 300 is coaxially coaxially formed in the female screw hole portion 281 of the connection shaft portion 280 of the shaft connection member 200c of the first diaphragm member 200 with its male screw portion 375. It is fastened. This means that the first diaphragm 200a and the second diaphragm 300a are integrally formed together with the axial connection member 200c and the axial valve body member 300c by the mutual connection of the axial connection member 200c and the axial valve body member 300c. It means that it is a body.

  With 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 valve to discharge the pressure from the pump. The opening degree (opening degree of the valve part) of the valve body part 370b with the annular valve seat part 133a is controlled at a constant interval in accordance with the displacement of the above-mentioned integral structure due to the fluctuation of the liquid pressure of the liquid, and the constant flow rate It is selected to flow out as a liquid. Accordingly, the main set pressure in the first pressure control chamber Sa and the sub-set pressure in the second pressure control chamber Ra become the constant pressure of the first compressed air flow and the second set 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 liquid pressure of the liquid acts on the second diaphragm 300a from the second liquid chamber Rb side and the first diaphragm It acts on 200a from the first liquid chamber Sb side.

  In accordance with this, the control valve is configured such that the above-described integrated structure operates under the set pressure in the first pressure control chamber Sa and the set pressure in the second pressure control chamber Ra that act so as to face each other. The interval (valve) of the seat portion 373a of the valve body portion 370b with respect to the annular valve seat portion 133a according to the fluid pressure in the first fluid chamber Sb and the fluid pressure in the second fluid chamber Rb acting to oppose the set pressure. (The degree of opening of the section) is controlled at a constant interval. This means that the control valve controls the liquid discharged from the pump to a constant flow rate corresponding to a constant interval of the seating portion 373a of the valve body portion 370b with respect to the annular valve seat portion 133a, and the inflow side communication passage. 131, the second liquid chamber Rb, the central communication path 133, the first liquid chamber Sb, and the outflow-side communication path 132 to flow out of the outflow cylinder 170.

  In such a state, when the liquid pressure of the liquid discharged from the pump fluctuates, in response to the fluctuation, the control valve causes the integrated component to move the valve body 370b under the two set pressures. The opening of the seating portion 373a with respect to the annular valve seat 133a is controlled so as to be maintained so as to maintain the above-mentioned constant opening. In other words, the control valve displaces the integrated component in accordance with a change in the liquid pressure of the liquid discharged from the pump under the two set pressures, and discharges the discharged liquid at a constant flow rate on the outflow side. Control so that it flows out to.

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

  Therefore, even when the control valve is in the operating state, particles 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. As a matter of course, it does not occur that the particles are mixed into the liquid, and even minute particles having a size of several nanometers can be minimized (minimized). Further, such a situation is similarly established even when the shaft-shaped connecting member 200c is seated on the annular valve seat portion 133a or separated from the annular valve seat portion 133a in the operation state of the control valve.

  From the above, in the control valve, the liquid flowing in the first liquid chamber Sb or the second liquid chamber Rb minimizes even the incorporation of minute particles having a size of several nm as described above. By doing so, it is maintained substantially clean, and flows through the annular valve seat 133a, 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 pipe route. .

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

  In addition, since the first diaphragm 200a and the second diaphragm 300a in the form of a film are formed by extrusion molding of PFA as described above, the generation of particles of several nm in size can be minimized and the flexibility is improved. It can be formed as a diaphragm that can maintain excellent long life. Therefore, even if such a control valve having the first diaphragm 200a and the second diaphragm 300a is applied to the semiconductor manufacturing apparatus, the first diaphragm 200a and the second diaphragm 300a maintain the bending operation well over a long period of time. The control valve is applied to a semiconductor manufacturing apparatus and can maintain a good function for a long time.

(2nd Embodiment)
FIG. 4 shows a main part of a second embodiment of the present invention. In the second embodiment, the first diaphragm member 200 described in the first embodiment includes a disk-shaped auxiliary member 290 in addition to the diaphragm 200a, the reinforcing annular body 200b, and the shaft-shaped connecting member 200c. I have.

  The auxiliary member 290 is formed in a disk shape by PFA, and the auxiliary member 290 plays a role of regulating the movable range of the curved displacement portion 230 of the diaphragm 200a. The lower surface of the auxiliary member 290 is coaxially joined to the first diaphragm 200a from the upper surface 240 side by laser welding. In addition, the auxiliary member 290 is set so that the outer diameter and the thickness thereof suppress the bending of the first diaphragm 200a and regulate the movable range of the first diaphragm 200a. Other configurations are the same as those in the first embodiment.

  In the second embodiment configured as described above, since the auxiliary member 290 is joined to the first diaphragm 200a by laser welding as described above, in the first diaphragm member 200, the first diaphragm 200a is In the bending displacement part 230, the bending displacement can be favorably performed 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 the diaphragm control valve according to the present invention. In the third embodiment, the diaphragm control valve joins the reinforcing annular body 200b to the outer peripheral portion 210 of the first diaphragm 200a by laser welding from the upper surface 240 side as shown in either of FIGS. The first diaphragm member thus formed is employed in place of the first diaphragm member 200 described in the first embodiment. The first diaphragm member according to the third embodiment is also denoted by reference numeral 200, similarly to the first embodiment.

  In the control valve according to the third embodiment, the first diaphragm member 200 includes a first diaphragm 200a, an annular reinforcing member 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 to the central portion 220 of the first diaphragm 200a from the lower surface 250 side of the disc-shaped base 260 in the same manner as in the first embodiment. They are joined (see FIG. 6). Further, unlike the first embodiment, the reinforcing annular body 200b is joined by laser welding from the upper surface 240 side at the outer peripheral portion 210 of the diaphragm 200a (see FIG. 6). Other configurations are the same as those in the first embodiment.

  In the third embodiment configured as described above, in the first diaphragm member 200 configured as described above, the outer periphery of the first diaphragm 200a is set in a state in which the reinforcing annular body 200b is positioned on the upper side. At the portion 210, together with the reinforcing annular body 200b, the inner peripheral side of the outer annular wall 152 of the opening wall 150a of the upper peripheral wall 150 of the middle housing member 100b is fitted, and the upper peripheral wall of the middle housing member 100b is fitted. It is sandwiched between the inner annular wall 151 of the 150 opening wall 150a and the inner annular wall 191 of the opening wall 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, the first diaphragm 200a is thin because of such a joint configuration. Even if it is difficult, the reinforcing annular body 200b exerts a reinforcing function favorably on the first diaphragm 200a, and the first diaphragm 200a is placed on the inner peripheral side of the outer annular wall 152 of the upper peripheral wall 150 of the middle housing member 100b. It can be easily fitted to Accordingly, the first diaphragm 200a can be properly seated on the inner annular wall 151 together with the reinforcing annular body 200b, and can be sandwiched 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 a main part of a fourth embodiment of the present invention. In the fourth embodiment, the first diaphragm member 200 described in the third embodiment is different from the second embodiment in addition to the first diaphragm 200a, the reinforcing annular body 200b, and the shaft-like connecting member 200c. The disk-shaped auxiliary member 290 is provided.

  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 lower surface on the inner peripheral side of the reinforcing annular body 200b. I have. 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 first diaphragm 200a on the inner peripheral side of the reinforcing annular body 200b from the upper surface 240 side. Even if they are joined by welding, in the first diaphragm member 200, the first diaphragm 200a can be satisfactorily curved and displaced by the curved displacement part 230 without bending. Other configurations, operations, 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 the 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 section instead of the female screw hole 281 in the connecting shaft 280 thereof. Along with the concave portion 282, the second diaphragm member 300 includes a protruding portion 370d having a trapezoidal vertical cross section instead of the male screw portion 375 in the distal rod portion 370c of the axial valve body member 300c.

  The concave portion 282 is formed coaxially in the connecting shaft portion 280 in a trapezoidal longitudinal cross section from the extending end side thereof, 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 vertical cross-section so as to extend coaxially and taper from the large-diameter shaft portion 374 of the shaft-shaped valve member 300c toward the shaft-shaped connecting member 200c. ing.

  The axial valve body member 300c thus configured is engaged with the projection 370d in the recess 282 of the connecting shaft 280 so as to be mutually separable. Other configurations are the same as those in the first embodiment.

  In the fifth embodiment configured as described above, unlike the integral structure of the control valve according to the first embodiment, the axial valve body member 300c of the second diaphragm member 300 has a protruding portion. At 370d, the first diaphragm member 200 is detachably engaged with the concave portion 282 of the shaft-like connecting member 200c. This means that the first diaphragm 200a and the second diaphragm 300a can be separated from each other by the separable connection between the shaft-like connecting member 200c and the shaft-like valve body member 300c, together with the shaft-like connecting member 200c and the shaft-like valve body member 300c. Different from the above-mentioned integral structure, it means that it is a separable structure.

  Accordingly, in a state where the control valve controls the discharge liquid from the pump to flow out as a liquid having a constant flow rate as in the first embodiment, the hydraulic pressure on the outflow side of the control valve is controlled. When the load suddenly increases and the fluid pressure in the outflow cylinder 160 and the first fluid chamber Sb is suddenly increased, the fluid pressure of the first diaphragm 200a toward the first pressure regulating chamber Sa is increased. .

  For this reason, the first diaphragm 200a bends and displaces toward the first pressure regulation chamber Sa, so that the first diaphragm 200a exerts a tensile force on the shaft-shaped connecting member 200c toward the first pressure regulation chamber Sa.

  However, as described above, in the separable structure, the axial connecting member 200c and the axial valve body member 300c are separable from each other, so that the axial connecting member 200c is separated from the axial valve body member 300c. Then, it only moves to the first pressure regulation chamber Sa side, and the axial valve body member 300c can be maintained at the same position. Therefore, the frictional engagement of the seat portion 373b with the annular valve seat portion 133a, which tends to occur when the above-described tensile force also acts on the valve body portion 370b, does not occur. There is no possibility that particles are generated from the valve seat 133a.

  Based on such an operation and effect, the operation and operation and effect as 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 the diaphragm control valve according to the present invention. In the sixth embodiment, the fifth embodiment is different from the fifth embodiment in that, 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 similarly to the third embodiment. Only the difference is in the point, and the other configuration is the same as that of the fifth embodiment.

  Therefore, in the sixth embodiment configured as described above, the operation and effect as the control valve based on the separable integrated structure described in the fifth embodiment can be similarly achieved.

  In carrying out the present invention, the following various modifications are possible without being limited to the above embodiments.

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

  The compression molding method refers to a method in which PFA is filled in a mold and compressed into a film, and as in the case where the diaphragm 200a is molded by an extrusion molding method, chemical resistance, low elution property, flexibility and length. It is a film-like diaphragm with excellent life and high smoothness, and can be formed as a diaphragm capable of minimizing dusting of particles of several nm in size. With this, the same operation and effect as the above embodiment can be achieved.

(2) Further, in practicing the present invention, the diaphragm member 200 may be understood 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 has an 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 121 of the peripheral wall 120 of the middle housing member 100b and the inner annular wall 161 of the peripheral wall 160 of the upper housing member 100c.

(4) In practicing the present invention, the middle housing member 100b of the housing 100 is provided with the middle wall 130 at an axially intermediate portion of the cylindrical peripheral wall composed of the upper and lower peripheral walls 150 and 140, and the inside of the cylindrical peripheral wall is provided. May be grasped as a partition wall for forming the accommodation room R on the bottom housing member 100a side and forming the accommodation room S on the upper housing member 100c side.

(5) In practicing 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, but may be any fluororesin.

100: housing, 100a: bottom housing member,
100b: middle housing member, 100c: upper housing member, 110: bottom wall,
130 ... middle side wall, 131 ... inflow side communication passage, 132 ... outflow side communication passage,
133: central communication passage, 133a: annular valve seat, 120, 160: peripheral wall,
140, 150: cylindrical peripheral wall, 180: upper wall, 160: inflow cylinder, 170: outflow cylinder,
200: diaphragm member, 200a, 300a: diaphragm,
200b, 300b: annular member for reinforcement, 200c: axial connecting member,
210, 310: outer peripheral portion, 282: concave portion, 290: plate-shaped auxiliary member,
300c: axial valve body member, 360: circular substrate, 370: rod,
370b: valve body portion, 370d: projecting portion, Ra, Sa: pressure regulating chamber,
Rb, Sb: liquid chamber.

Claims (6)

In a diaphragm type control valve that controls the flow rate of a liquid such as a high-purity chemical solution or ultrapure water flowing into an inflow side,
A cylindrical peripheral wall, two opposing walls facing each other so as to close the cylindrical peripheral wall from both axial openings, and an inside of the cylindrical peripheral wall, one of the two opposing walls. A housing having a first accommodating chamber therebetween and a partition wall intersecting the other opposing wall to form a second accommodating chamber;
A first diaphragm member housed in the first housing chamber and having a film-shaped first diaphragm made of PFA and a shaft-like connecting member made of fluororesin;
A second diaphragm member housed in the second housing chamber and having a PFA film-shaped second diaphragm and a fluororesin axial valve body member;
In the first diaphragm member,
The first diaphragm is supported at an outer peripheral portion thereof in an axially intermediate portion of the first accommodation chamber side peripheral wall portion of the cylindrical peripheral wall, and divides the inside of the first accommodation chamber into the one of the first accommodation chamber. A first pressure regulation chamber is formed on the opposite wall side, and a first liquid chamber is partitioned on the partition wall side;
The shaft-like connecting member is joined at its base to the center of the first diaphragm on the lower surface side of the first diaphragm by laser welding, and is connected to the first liquid chamber from the center of the first diaphragm. Has been extended to
In the second diaphragm member,
The second diaphragm is supported at an outer peripheral portion thereof in an axially intermediate portion of the second housing chamber side peripheral wall portion of the cylindrical peripheral wall. The interior of the second storage chamber is partitioned so that a second pressure regulation chamber is formed on the other opposing wall side and a second liquid chamber is formed on the partition wall side,
The shaft-shaped valve body member has a base joined to the center of the second diaphragm by laser welding on the upper surface side of the second diaphragm, and the base from the base to the center of the second liquid chamber and the partition wall. A rod coupled to an extended end of the shaft-like connecting member through a formed central communication passage,
The partition wall is an annular valve seat portion that forms a valve portion together with the valve body portion at the second liquid chamber side opening of the central communication passage so as to face the valve body portion of the axial valve body member. Having,
The cylindrical peripheral wall includes an inflow passage through which the liquid flows into the first liquid chamber from the inflow side, and the liquid in the first liquid chamber through the annular valve seat, the central communication passage, and the first liquid chamber. An outflow channel for outflow to the outflow side is provided,
In a state where the first diaphragm receives the set pressure generated in the first pressure regulation chamber and the second diaphragm receives the set pressure generated in the second pressure regulation chamber, the first diaphragm and the second diaphragm are Depending on the fluctuation of the liquid pressure of the liquid on the inflow side, the opening degree of the valve body with the annular valve seat is adjusted via the shaft-like connecting member and the shaft-like valve body which are connected to each other. By controlling the opening degree to be constant, the liquid on the inflow side is supplied to the inflow path, the second liquid chamber, the annular valve seat portion, and the center connection at a constant flow rate corresponding to the constant opening degree. A diaphragm-type control valve characterized by flowing out to the outflow side through a passage, the first liquid chamber, and the outflow path. In a diaphragm type control valve that controls the flow rate of a liquid such as a high-purity chemical solution or ultrapure water flowing into an inflow side,
A cylindrical peripheral wall, two opposing walls facing each other so as to close the cylindrical peripheral wall from both axial openings, and an inside of the cylindrical peripheral wall, one of the two opposing walls. A housing having a first accommodating chamber therebetween and a partition wall intersecting the other opposing wall to form a second accommodating chamber;
A first diaphragm member housed in the first housing chamber and having a film-shaped first diaphragm made of PFA and a shaft-like connecting member made of fluororesin;
A second diaphragm member housed in the second housing chamber and having a PFA film-shaped second diaphragm and a fluororesin axial valve body member;
In the first diaphragm member,
The first diaphragm is supported at an outer peripheral portion thereof in an axially intermediate portion of the first accommodation chamber side peripheral wall portion of the cylindrical peripheral wall, and divides the inside of the first accommodation chamber into the one of the first accommodation chamber. A first pressure regulation chamber is formed on the opposite wall side, and a first liquid chamber is partitioned on the partition wall side;
The shaft-like connecting member is joined at its base to the center of the first diaphragm on the lower surface side of the first diaphragm by laser welding, and is connected to the first liquid chamber from the center of the first diaphragm. Has been extended to
In the second diaphragm member,
The second diaphragm is supported at an outer peripheral portion thereof in an axially intermediate portion of the second housing chamber side peripheral wall portion of the cylindrical peripheral wall. The interior of the second storage chamber is partitioned so that a second pressure regulation chamber is formed on the other opposing wall side and a second liquid chamber is formed on the partition wall side,
The shaft-shaped valve body member has a base joined to the center of the second diaphragm by laser welding on the upper surface side of the second diaphragm, and the base from the base to the center of the second liquid chamber and the partition wall. A rod that is connected to the extending end of the shaft-like connecting member so as to be separable from each other through a central communication path formed,
The partition wall is an annular valve seat portion that forms a valve portion together with the valve body portion at the second liquid chamber side opening of the central communication passage so as to face the valve body portion of the axial valve body member. Having,
The cylindrical peripheral wall includes an inflow passage through which the liquid flows into the first liquid chamber from the inflow side, and the liquid in the first liquid chamber through the annular valve seat, the central communication passage, and the first liquid chamber. An outflow channel for outflow to the outflow side is provided,
In a state where the first diaphragm receives the set pressure generated in the first pressure regulation chamber and the second diaphragm receives the set pressure generated in the second pressure regulation chamber, the first diaphragm and the second diaphragm are According to the fluctuation of the liquid pressure of the liquid on the inflow side, through the shaft-shaped connecting member and the shaft-shaped valve body member which are connected to be separable from each other, the valve body portion and the annular valve seat portion are By controlling the opening to a constant opening, at a constant flow rate according to the constant opening, the liquid on the inflow side, the inflow path, the second liquid chamber, the annular valve seat portion, A diaphragm-type control valve, wherein the valve flows out to the outflow side through the central communication path, the first liquid chamber, and the outflow path.   The said 1st diaphragm member is provided with the reinforcing ring body made of a fluororesin joined by laser welding to the said lower surface or the said upper surface of the said 1st diaphragm along the outer peripheral part, The 1st or 2nd characterized by the above-mentioned. 4. The diaphragm control valve according to claim 1.   The first diaphragm member is coaxially joined to the first diaphragm by laser welding from the upper surface thereof so as to suppress the bending 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.   The diaphragm according to any one of claims 1 to 4, wherein the first diaphragm is formed into a film by extruding or compressing PFA together with the second diaphragm. Control valve.   The diaphragm type control valve according to claim 5, wherein the first diaphragm, together with the second diaphragm, has a thickness within a range of 0.1 (mm) or more and 0.6 (mm) or less. .

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