JP2020026846A - Diaphragm member, and diaphragm valve using diaphragm member - Google Patents

Abstract

To provide a diaphragm member formed as a diaphragm structure to which laser welding is applied for connecting an auxiliary shaft and a central part of a diaphragm even when the diaphragm is as thin as a film while selecting a film-like PFA which can secure flexibility and longevity, as a forming material for the diaphragm which can minimize the emission of several nm dust and utilizing the appropriate fluorine-contained resin auxiliary shaft in consideration of easy assembly with another member, and to provide a diaphragm valve using the diaphragm member.SOLUTION: A diaphragm member 200 includes a film-like diaphragm 200a formed of the PFA, and an auxiliary shaft 200c laser-welded to a central part of the diaphragm 200a.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a diaphragm member suitable for being used as a diaphragm valve for flowing a liquid such as a high-purity chemical solution or ultrapure water in a semiconductor manufacturing apparatus, and a diaphragm valve using the diaphragm member.

  Conventionally, a diaphragm valve of this type includes a housing, a diaphragm supported in the housing so as to be capable of being displaced in an axially curved manner, and a diaphragm that is assembled to the housing and displaces the diaphragm in an axially curved manner. And a driving mechanism for driving.

  When a diaphragm valve having such a configuration is used in a semiconductor manufacturing apparatus, a highly corrosive chemical such as a strong acid or a strong alkali is used as a high-purity chemical in a cleaning step or a stripping step in the semiconductor manufacturing apparatus. As a material for forming the diaphragm in the diaphragm 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 diaphragm valve is not allowed, it is preferable to use a fluororesin having a low elution property as a material for forming the diaphragm.

  In addition, due to the configuration of the diaphragm valve as described above, it is desirable to employ a fluororesin that 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 diaphragm valve having the above-described configuration, since liquid contamination by particles from the diaphragm valve is not allowed in the semiconductor manufacturing apparatus, the liquid flowing in the flow path system in the diaphragm valve is subjected to the diaphragm, It is necessary to isolate the diaphragm from the drive mechanism, and for that purpose, it is required that the diaphragm be 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 diaphragm 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, dust is generated from the curved displacement portion, albeit minutely. 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 diaphragm valve using the PFA diaphragm formed by the cutting process in this way, the operation of the diaphragm made of the PTFE 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 particles are extended or compressed, so that a small amount of dust is generated from the bending displacement portion.

  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 diaphragm valve is not allowed even for the generation of particles of several nm in size.

  However, as described above, the diaphragm valve using the diaphragm formed by the cutting process causes extension and compression on the surface of the curved displacement portion formed by the cutting process due to the operation, and accordingly, from the curved displacement portion. It is small, but generates dust.

  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 above-mentioned diaphragm valve is not allowed, and further improvement has been made to 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. It was recognized that adoption would lead to the improvement of the diaphragm described above.

  By the way, in the above-mentioned diaphragm valve, due to its configuration, when the diaphragm is displaced in a curved shape by the driving mechanism, the diaphragm is connected to the driving shaft of the driving mechanism at the center thereof.

  However, since the diaphragm is in the form of a film and is very thin as described above, it is not possible to form a connecting portion required for connecting to the drive shaft of the drive mechanism in the center of the diaphragm. Therefore, it is extremely difficult to connect the center of the diaphragm to the drive shaft of the drive mechanism without the connection.

  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 fact, they came up with the idea that it would be possible to use laser welding for connecting the central part of the PFA diaphragm to other members.

  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. In addition to selecting the material, taking into account the ease of assembling with other members, an appropriate fluororesin auxiliary shaft is used, and even if the diaphragm is thin as a film, the connection between the auxiliary shaft and the center of the diaphragm is possible. It is an object of the present invention to provide a diaphragm member configured as a diaphragm structure to which laser welding is applied, and a diaphragm valve using the diaphragm member.

In order to solve the above problems, according to the first aspect of the present invention, there is provided a diaphragm member,
A film-shaped diaphragm (200a) made of PFA applied to a diaphragm valve for flowing a liquid such as a high-purity chemical solution or ultrapure water;
A fluororesin auxiliary shaft (200c) coaxially joined by laser welding to the center of the film diaphragm.

  According to this, since the connection between the central portion of the diaphragm and the auxiliary shaft is made by laser welding, the auxiliary shaft and the central portion of the diaphragm can be satisfactorily connected.

  Further, the diaphragm is formed as a film-shaped diaphragm by PFA. Therefore, even if the diaphragm is a film, it is a diaphragm excellent in chemical resistance, low elution, flexibility and long life, and formed as a diaphragm capable of suppressing dust generation to a minimum (minimum). obtain.

  Also, even if the diaphragm is joined to the auxiliary shaft at its center, the auxiliary shaft can be positioned as a free component irrespective of the drive mechanism of the diaphragm valve except for the connection with the diaphragm. Therefore, after the diaphragm is joined to the auxiliary shaft, it is possible to ensure the convenience that the diaphragm member having the configuration of the diaphragm and the auxiliary shaft can be applied to diaphragm valves having various configurations.

  According to a second aspect of the present invention, in the diaphragm member according to the first aspect, the diaphragm member is made of a fluororesin that is laser-welded to one side surface of both surfaces of the diaphragm along the outer peripheral portion thereof. It is characterized by having a reinforcing ring.

  According to this, even if it is difficult to handle the diaphragm because it is thin like a film, the reinforcing annular body is formed on the diaphragm by the joining configuration by laser welding of the outer peripheral portion of the diaphragm and the reinforcing annular body as described above. On the other hand, it can exhibit a reinforcing function. Therefore, in addition to the operation and effect of the invention described in claim 1, the operation and effect that the diaphragm can be easily handled without bending even if the diaphragm is thin can be achieved.

  According to a third aspect of the present invention, in the diaphragm member according to the first or second aspect, the diaphragm is formed in a film shape by extruding or compressing PFA. Features.

  As described above, since the diaphragm is formed into a film shape by extruding or compressing PFA, dust generation is less than when a diaphragm is formed by cutting, and particles such as particles of several nm in size are generated. It is possible to form a diaphragm having a surface with a high smoothness such that even dust can be suppressed to a minimum (minimum) and excellent in chemical resistance, low elution, flexibility and long life.

  Further, as described above, since the diaphragm is formed into a film shape by extruding or compressing PFA, the diaphragm can be uniformly crystallized around its curved displacement portion, and the diaphragm can be formed. The service life can be further extended. As described above, the function and effect of the invention described in claim 1 or 2 can be further improved.

According to a fourth aspect of the present invention, in the diaphragm member according to the third aspect,
The auxiliary shaft has an outer diameter within a range of 1 (mm) or more and 4 (mm) or less,
The diaphragm has a thickness within a range of 0.1 (mm) or more and 0.5 (mm) or less.

  According to this, it is possible to more reliably achieve the same operation and effect as the operation and effect described in claim 3. Here, the auxiliary shaft having an outer diameter of 4 (mm) or less may be thermally deformed in the auxiliary shaft or the central portion of the diaphragm when the central portion of the diaphragm is thermally joined to the auxiliary shaft. The center part of the diaphragm is joined by laser welding, so that the joint between the auxiliary shaft and the center part of the diaphragm can be made without deformation even when the outer diameter of the auxiliary shaft is 4 (mm) or less. . The outer diameter of the auxiliary shaft is set to 1 (mm) because it is difficult to form an auxiliary shaft having an outer diameter of less than 1 (mm).

  The reason why the thickness of the diaphragm is set to 0.1 (mm) or more is that if the thickness is less than 0.1 (mm), the diaphragm is too thin and easily broken. Further, the reason why the thickness is set to 0.5 (mm) or less is that if the diaphragm is thicker than 0.5 (mm), it is too thick to bend easily.

According to the fifth aspect of the present invention, there is provided a diaphragm valve according to the fifth aspect.
When the valve is opened, a liquid such as a high-purity chemical solution or ultrapure water flows from the inflow side to the outflow side, and when the valve is closed, the flow of the liquid is shut off.

In the diaphragm valve,
A housing (100) having a cylindrical peripheral wall (130) and opposed walls (110, 140) formed on the cylindrical peripheral wall so as to oppose each other so as to close both axial openings thereof;
A partition wall (120) provided at an axially intermediate portion of the cylindrical peripheral wall to partition a hollow portion of the cylindrical peripheral wall between one of the opposing walls (140) and the other opposing wall (110). When,
A driving means (300) assembled between the one opposing wall (140) and the partition (120) within the hollow portion of the cylindrical peripheral wall;
PFA, which is provided in the housing and forms a liquid chamber (Ra) with the other opposite wall (110) and partitions the inside of the housing so as to form an air chamber (Rb) with the partition. It is composed of both a film diaphragm (200) and a fluororesin auxiliary shaft which is coaxially laser-welded to the center of the diaphragm and extends from the center. A diaphragm member fitted so as to be slidable in a through hole formed in the direction,
The drive means is provided integrally with a drive shaft coaxially connected to an extension end of the auxiliary shaft so as to be able to axially move toward the air chamber or in the opposite direction together with the auxiliary shaft of the diaphragm member. Become
The housing opposes the central portion of the diaphragm in the liquid chamber (Ra), and an annular valve seat portion (111c) that forms a valve portion together with the central portion. The liquid is supplied from the inflow side through the annular valve seat portion. An inflow path (110b, 112) for flowing into the liquid chamber and an outflow path (113, 110c) for flowing the liquid in the liquid chamber to the outflow side are provided on the other opposite wall (110),
When the diaphragm member seats the center portion of the diaphragm on the annular valve seat portion (111c) in conjunction with the axial movement of the drive shaft toward the other opposing wall (110) by the auxiliary shaft. The valve member is closed, and the diaphragm member is annularly connected to the central portion of the diaphragm by the auxiliary shaft in conjunction with the axial movement of the drive shaft toward the one opposite wall (140). It is characterized in that the valve is opened when it is separated from the valve seat.

  Thus, the diaphragm member is constituted by both the PFA film diaphragm and the fluororesin auxiliary shaft which is coaxially laser-welded to the central portion of the diaphragm and extends from the central portion. Is connected to the drive shaft of the drive mechanism via a partition.

  Here, even if the diaphragm is thin and difficult to handle, since the center of the diaphragm is laser-welded to the auxiliary shaft as described above, by holding the auxiliary shaft, the drive shaft can be connected to the center of the diaphragm. Thus, the drive shaft, the diaphragm and the auxiliary shaft can be easily connected.

  Thus, the diaphragm valve, when the diaphragm member, the auxiliary shaft, in conjunction with the axial movement of the drive shaft to the other opposite wall side, when the central portion of the diaphragm seated on the annular valve seat, When the valve is closed, and the diaphragm member is separated from the annular valve seat at the center of the diaphragm in conjunction with the axial movement of the drive shaft toward one of the opposing walls of the drive shaft by the auxiliary shaft. Then, the valve is opened.

  As a result, it is possible to achieve not only the same operation and effect as the invention described in claim 1 but also the above-described diaphragm and the diaphragm which can easily connect the drive shaft, the diaphragm, and the auxiliary shaft. A valve can be provided.

According to a sixth aspect of the present invention, in the diaphragm valve according to the fifth aspect,
The driving means is
The one side chamber (131a) and the other side chamber (131b) are slidably fitted in the hollow portion of the cylindrical peripheral wall between the one opposing wall and the partition wall along the axial direction thereof so as to form the one side chamber (131b). A piston (310) for defining the hollow portion of the cylindrical peripheral wall so as to be formed on the side and the partition side;
Biasing means (330) for biasing the piston toward one of the other side chamber and the one side chamber,
The drive shaft is a piston shaft integrally extended from the piston through the other side chamber and coaxially connected to an extension end of the auxiliary shaft of the diaphragm member.

  According to this, the diaphragm valve is configured such that, as the piston is urged by the urging means toward one of the other chamber and the one-side chamber to slide, the piston shaft interlocks with the piston to form the auxiliary shaft. As the diaphragm is seated on the annular valve seat at the center of the diaphragm or the piston slides against the urging means by the supply of air flow to one of the other chambers, the piston shaft moves in conjunction with the piston. Thus, the diaphragm functions as an air-operated diaphragm valve that separates the diaphragm from the annular valve seat at the center thereof through the auxiliary shaft.

  Even with such an air-operated diaphragm valve, the same function and effect as the invention described in claim 5 can be achieved.

According to a seventh aspect of the present invention, in the diaphragm valve according to the fifth aspect,
The driving means is
A solenoid (420) fitted along the axial direction between the one opposing wall and the partition in the hollow portion of the cylindrical peripheral wall;
A plunger (400b) that is axially inserted into the solenoid as a drive shaft and extends toward the partition wall;
Biasing means (400c) for biasing the plunger toward the partition wall or in the opposite direction,
The plunger is coaxially connected at its extended end to the extended end of the auxiliary shaft of the diaphragm member.

  According to this, as the plunger slides when the plunger is urged toward the partition wall by the urging means or urged in the opposite direction, the auxiliary shaft is interlocked to move the diaphragm at the center of the annular valve seat. As the plunger is seated on the part or slides in the direction opposite to the biasing direction by the biasing means against the biasing means based on the magnetic attraction force of the solenoid, the diaphragm is interlocked with the auxiliary shaft. Functions as an electromagnetically actuated diaphragm valve that separates the valve from the annular valve seat at its center.

  Even with such an electromagnetically actuated diaphragm valve, the same function and effect as the invention according to claim 5 can be achieved.

According to the eighth aspect of the present invention, in the diaphragm valve according to any one of the fifth to seventh aspects,
The diaphragm member includes a fluororesin reinforcing ring (200b) that is laser-welded to one of the two surfaces of the diaphragm along the outer peripheral portion thereof.

  According to this, it is possible to provide a diaphragm valve that can achieve the same operation and effect as the invention described in claim 2.

According to a ninth aspect of the present invention, in the diaphragm valve according to any one of the fifth to eighth aspects,
The diaphragm member is formed in a film shape by extruding or compressing PFA with the diaphragm.

  According to this, it is possible to provide a diaphragm valve capable of achieving the same operation and effect as the operation and effect of the invention described in claim 3.

According to a tenth aspect of the present invention, in the diaphragm valve according to the ninth aspect,
In the diaphragm member, the auxiliary shaft has an outer diameter within a range of 1 (mm) or more and 4 (mm) or less, and the diaphragm has a diameter of 0.1 (mm) or more and 0.5 (mm) or less. It has a thickness within the range.

  According to this, it is possible to provide a diaphragm valve that can achieve the same operation and effect as the invention described in claim 4.

  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 valve to which the present invention is applied. FIG. 5 is a process diagram showing a process of laser-welding a central portion of the diaphragm of the diaphragm member to the auxiliary shaft in the first embodiment. It is sectional drawing for demonstrating the laser welding with respect to the auxiliary shaft of the center part of a diaphragm in the said 1st Embodiment. FIG. 5 is a process diagram showing a process of laser welding an outer peripheral portion of the diaphragm of the diaphragm member of the first embodiment to a reinforcing annular body. It is sectional drawing for demonstrating the laser welding of the reinforcement annular body with respect to the outer peripheral part of a diaphragm in the said 1st Embodiment. It is a fragmentary longitudinal section showing the important section of a 2nd embodiment of a diaphragm valve to which the present invention is applied. It is sectional drawing for demonstrating the laser welding of the reinforcement annular body with respect to the outer peripheral part of a diaphragm in the said 2nd Embodiment. It is a longitudinal section showing a 3rd embodiment of a diaphragm valve to which the present invention is applied. It is a longitudinal section showing a 4th embodiment of a diaphragm valve to which the present invention is applied.

  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 valve to which the present invention is applied. As the diaphragm valve, an air-operated diaphragm valve applied to a semiconductor manufacturing apparatus for manufacturing a semiconductor element is employed.

  The diaphragm valve is interposed in a piping system of the semiconductor manufacturing apparatus, and is configured to flow a liquid flowing through the piping system from an upstream side to a downstream side. In the first embodiment, the liquid refers to a liquid such as a high-purity chemical solution or ultrapure water, and is supplied from the liquid supply source of the semiconductor manufacturing apparatus to the piping system. Further, the liquid is required to be clean due to the nature of the semiconductor manufacturing apparatus.

  As shown in FIG. 1, the diaphragm valve includes a cylindrical housing 100, a diaphragm member 200 and an air-operated driving mechanism 300 assembled in the cylindrical housing 100, and is configured as a normally-closed diaphragm valve. ing. In the first embodiment, the pneumatic drive mechanism 300 is also referred to as a drive mechanism 300 below.

  The cylindrical housing 100 includes a lower housing member 100a and an upper housing member 100b.

  As shown in FIG. 1, the lower housing member 100a includes a bottom wall 110 and a partition wall 120. The bottom wall 110 includes a bottom wall main body 110a, an inflow cylinder 110b, and an outflow cylinder 110c. .

  The bottom wall main body 110a is formed in a rectangular cross section. The bottom wall main body 110a has an upper wall 111 as shown in FIG.

  Here, the upper wall portion 111 includes an inner annular wall portion 111a and an outer annular wall portion 111b, and the inner annular wall portion 111a is formed on the center side of the upper wall portion 111. The outer annular wall portion 111b is formed to protrude annularly upward from the inner annular wall portion 111a on the outer peripheral side of the inner annular wall portion 111a.

  Further, the bottom wall main body 110a has an annular valve seat portion 111c, and the annular valve seat portion 111c coaxially and annularly projects from the central portion of the inner annular wall portion 111a to the partition wall 120 side. Is formed. Here, the annular valve seat portion 111c is formed so as to communicate with an inner end opening of an inflow passage portion 112 (described later).

  The bottom wall main body 110a has an inflow passage portion 112 and an outflow passage portion 113. The inflow passage portion 112 extends from the annular valve seat portion 111c toward the inflow cylinder 110b within the bottom wall main body 110a. It is formed as follows. The inflow passage portion 112 communicates with the inside of the annular valve seat portion 111c at the inner end opening.

  On the other hand, the outflow passage portion 113 is formed in the bottom wall main body 110a so as to extend from a part of the inner annular wall portion 111a toward the outflow tube 110c. Here, the outflow channel portion 113 is formed in the bottom wall main body 110a so as to open from a part of the inner annular wall portion 111a into the liquid chamber Ra (described later) at the inner end opening. .

  The inflow tube 110b is formed in the bottom wall main body 110a so as to extend outward from the outer end opening of the inflow passage portion 112, and the inflow tube 110b flows into the upstream side of the piping system. It plays the role of connecting the road section 112. On the other hand, the outflow tube 110c plays a role of communicating the outflow path portion 113 with the downstream side of the piping system.

  As shown in FIG. 1, the partition 120 has a partition main body 120a and an annular flange 120b, and the partition main body 120a has an outer annular wall portion of an upper wall portion 111 of a bottom wall main body 110a at a lower wall portion thereof. 111b, and is seated on the inner annular wall 111a via the diaphragm 200a of the diaphragm member 200 and the reinforcing annular body 200b (described later).

  Further, the annular flange 120b is formed so as to project annularly outward in the radial direction from the axially intermediate portion of the bottom wall main body 110a, and the annular flange 120b is formed on the upper wall portion 111 of the bottom wall main body 110a. Is coaxially seated on the outer annular wall portion 111b. In this manner, the partition wall 120 is coaxially assembled to the bottom wall main body 110a from above through the diaphragm 200a and the reinforcing annular body 200b.

  In addition, the partition 120 has a communication path 121, and the communication path 121 is formed in an L shape in the partition main body 120a as shown in FIG. Here, the communication passage 121 is open to the outside of the partition wall 120 at the outer end opening portion, and the inner end opening portion of the communication passage 121 is located between the diaphragm 200a and the partition wall body 120a. It is open in the formed air chamber Rb (described later).

  The upper housing member 100b is formed in a rectangular cross section, and the upper housing member 100b is configured by a peripheral wall 130 and an upper wall 140. The peripheral wall 130 extends downward from the upper wall 140 in a tubular shape, and the hollow portion 131 of the peripheral wall 130 is formed in a circular cross section on the inner peripheral surface. In addition, the peripheral wall 130 is coaxially and airtightly fitted to the partition main body 120a of the partition 120 from above through an O-ring 123 at its extended end opening, and sits on the annular flange 120b. I have.

  As shown in FIG. 1, the diaphragm member 200 includes a diaphragm 200a, an annular reinforcing member 200b, and an auxiliary shaft 200c. The diaphragm 200a is sandwiched at its outer peripheral portion 210 between the bottom wall main body 110a of the bottom wall 110 and the partition wall main body 120a of the partition wall 120 via the reinforcing annular body 200b. Thus, the diaphragm 200a moves the liquid chamber Ra and the air chamber between the inner annular wall 111a and the partition main body 120a on the inner peripheral side of the outer annular wall 111b of the upper wall 111 of the bottom wall main body 110a. Rb.

  Here, the liquid flowing from the upstream side of the piping system of the semiconductor manufacturing apparatus through the inflow cylinder 110b and the inflow path 112 of the bottom wall 110 flows into the liquid chamber Ra through the annular valve seat 111c. Thereby, the liquid generates a liquid pressure acting on the lower surface 220 of the diaphragm 200a in the liquid chamber Ra. On the other hand, outside air flows into the air chamber Rb through the communication passage 121 of the partition 120. Thereby, the outside air generates air pressure (atmospheric pressure) acting on the upper surface 230 of the diaphragm 200a in the air chamber Rb.

  The diaphragm 200a is formed as a disk-shaped and film-shaped diaphragm with a predetermined fluorine resin.

  In the first embodiment, since the diaphragm 200a is in contact with a high-purity chemical such as a highly corrosive chemical such as a strong acid or a strong alkali due to the configuration as the diaphragm valve, the diaphragm 200a is resistant to acid and alkali. It is desirable that the compound has excellent chemical resistance.

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

  In addition, since the diaphragm 200a repeatedly bends and displaces each time the diaphragm valve is opened and closed, it is desirable that the diaphragm 200a has at least excellent flexibility and long life.

  Therefore, in the first embodiment, the above-mentioned predetermined fluororesin is a tetrafluoroethylene / perfluoroalkyl which is excellent in chemical resistance, low elution, heat resistance and corrosion resistance, and can ensure flexibility and long life. Vinyl ether copolymer (PFA) is employed. In the first embodiment, PFA is also used as a material for forming the cylindrical housing 100 and the partition 120.

  The diaphragm 200a is formed of PFA so as to have a thickness within a predetermined thickness range, for example, 0.5 (mm), as a film-shaped diaphragm. In the first embodiment, the predetermined thickness range refers to a thickness range of 0.1 (mm) or more and 0.5 (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 diaphragm 200a is too thin and easily broken. The reason why the thickness is set to 0.5 (mm) or less is that if the diaphragm 200a is thicker than 0.5 (mm), it is too thick to bend easily.

  The diaphragm 200a configured as described above plays a role as a valve body (hereinafter, also referred to as the valve body 240) facing the annular valve seat 111c at the center 240 thereof. This means that the valve body 240, together with the annular valve seat 111c, forms a valve portion of the diaphragm valve.

  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 220 side of the diaphragm 200a. I have. Thereby, the reinforcing annular body 200b is formed integrally with the outer peripheral portion 210 of the diaphragm 200a.

  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 as described later. Here, the reinforcing annular body 200b has an outer diameter equal to the outer diameter of the diaphragm 200a, and the axial width and thickness of the reinforcing annular body 200b are handled by reinforcing the film-like diaphragm 200a. Each value is set to a value suitable for facilitation.

  The auxiliary shaft 200c has a columnar shape, and the lower portion of the auxiliary shaft 200c is joined to the central portion 240 of the diaphragm 200a by laser welding. Thus, the auxiliary shaft 200c is formed integrally with the central portion 240 of the diaphragm 200a. The auxiliary shaft 200c has a female screw hole 260, and the female screw hole 260 is formed coaxially on the auxiliary shaft 200c from the upper side.

  In the first embodiment, the auxiliary shaft 200c is formed by injection molding into a column using PFA as described later. The outer diameter of the auxiliary shaft 200c is set to a value within a range from 1 (mm) to 4 (mm).

  Here, the outer diameter of the auxiliary shaft is set to 4 (mm) or less. When the auxiliary shaft having an outer diameter of 4 (mm) or less is joined to the center of the diaphragm by heat, the auxiliary shaft or the center of the diaphragm is formed. However, if the auxiliary shaft and the central portion of the diaphragm are joined by laser welding, the joint between the auxiliary shaft and the central portion of the diaphragm is not deformed. The reason why the outer diameter of the auxiliary shaft is 1 (mm) or more is that it is difficult to form an auxiliary shaft having an outer diameter of less than 1 (mm).

  The lower part of the auxiliary shaft 200c is formed so as to be orthogonal to the axis of the auxiliary shaft 200c at the lower surface part a on the center side, and the outer lower surface part b of the lower part of the auxiliary shaft 200c is (See FIG. 3).

  The auxiliary shaft 200c thus configured is slidably fitted from above in a through-hole 122 (see FIG. 1) formed coaxially with the partition wall body 120a, and is driven as described later. The piston 300 is connected to the piston shaft 320 of the mechanism 300 in the through hole 122. In the present embodiment, the axial length of the auxiliary shaft 200c is shorter than the axial thickness of the partition wall body 120a.

  The diaphragm member 200 configured as described above is integrally formed with the diaphragm 200a, the annular reinforcing member 200b, and the auxiliary shaft 200c. Thus, when the auxiliary shaft 200c is pushed toward the liquid chamber Ra by the piston shaft 320 under the urging force of the coil spring 330 as described later, the diaphragm 200 is moved by the bending displacement portion thereof. The valve 200 is pushed by the liquid chamber Ra to be displaced in a curved shape, and the valve body 240 is seated on the annular valve seat 111c to close the valve. This means that the diaphragm valve closes. In addition, the bending displacement part of the diaphragm 200a refers to a film-like part between the outer peripheral part and the central part of the diaphragm 200a.

  On the other hand, the auxiliary shaft 200c moves downwardly while displacing the diaphragm 200a in a curved shape in conjunction with the piston shaft 320 that slides against the urging force of the coil spring 330 according to the air pressure in the lower chamber 131a as described later. When sliding to the side chamber 131b side, the diaphragm 200a is moved. At the valve body 240, the valve is opened by moving away from the annular valve seat 111c. This means that the diaphragm valve opens.

  The drive mechanism 300 is assembled inside the housing 100 as shown in FIG. The drive mechanism 300 includes a piston 310, a piston shaft 320, and a coil spring 330.

  The piston 310 is air-tightly slidably fitted through the O-ring 311 in the hollow portion 131 of the peripheral wall 130 of the housing member 100b. The hollow portion 131 is partitioned into an upper chamber 131a and a lower chamber 131b. In the first embodiment, the piston 310 is formed of PFA together with the piston shaft 320.

  Here, the upper chamber 131a is opened to the outside of the housing member 100b through an annular groove 141, a communication path 142, and an opening 143 formed in the upper wall 140 of the housing member 100b.

  The annular groove 141 is formed coaxially in the upper wall 140 from the inside of the upper chamber 131a. The opening 143 is formed in the outer peripheral portion of the upper wall 140, and the communication path 142 is formed inside the upper wall 140 so that the annular groove 141 communicates with the opening 143.

  On the other hand, the lower chamber 131b is connected to a compressed air flow supply source (not shown) through a communication passage 133 and an opening 134 formed in the peripheral wall 130. Thus, the compressed air flow from the compressed air flow supply source is supplied to the inside of the lower chamber 131b through the opening 134 and the communication path 133.

  The opening 134 is formed in a part of the peripheral wall 130 below the opening 143 so as to communicate with the inside of the lower chamber 131b through the communication passage 133. The communication passage 133 is formed in a part of the peripheral wall 130 so as to communicate the opening 134 with the inside of the lower chamber 131b.

  The piston shaft 320 is formed so as to extend coaxially and integrally from the piston 310. As shown in FIG. 1, the piston shaft 320 includes a shaft main body 320a and a shaft-like external thread 320b. The shaft main body 320a extends coaxially from the piston 310 through the lower chamber 131b. It is slidably fitted through the O-ring 321 in the through hole 122 of the partition wall main body 120a.

  The axial male screw part 320b extends coaxially and consistently from the extending end of the shaft main body part 320a, and the axial male screw part 320b is fastened into the female screw hole 260 of the auxiliary shaft 200c. Have been. Thus, the piston shaft 320a is slidably coaxially connected to the auxiliary shaft 200c in the through hole 122 of the partition wall main body 120a.

  As shown in FIG. 1, the coil spring 330 is fitted in the annular groove 141 of the upper wall 140, and the coil spring 330 is sandwiched between the bottom of the annular groove 141 and the piston 310, and 310 is urged toward the lower chamber 131b.

  In the driving mechanism 300 configured as described above, when the air pressure due to the compressed air flow from the compressed air supply source is not generated in the lower chamber 131b, the piston 310 is moved by the urging force of the coil spring 330. 131a, the piston shaft 320 pushes the auxiliary shaft 200c toward the annular valve seat portion 111c, thereby moving the diaphragm 200a at the center portion 240 (valve body portion 240) of the annular valve seat portion 111c. Displaced to be seated.

  On the other hand, when the compressed air flow from the compressed air supply source is supplied into the lower chamber 131b through the opening 134 and the communication path 133, the piston 310 moves according to the air pressure of the compressed air in the lower chamber 131b. The air in the upper chamber 131a slides toward the upper chamber 131a while discharging the air in the upper chamber 131a from the annular groove 141, the communication path 142, and the opening 143 to the outside against the urging force of the coil spring 330, and the piston shaft 320 is moved. In conjunction with the sliding direction of the piston 310, the diaphragm 200a is displaced in a curved manner in a direction away from the annular valve seat portion 111c at the valve body, which is the central portion 240 thereof, via the auxiliary shaft 200c in cooperation with the sliding direction.

  Next, a method of laser welding the diaphragm 200a, the reinforcing annular body 200b, and the auxiliary shaft 200c in the diaphragm member 200 in manufacturing the diaphragm valve configured as described above will be described.

  In performing laser welding of the diaphragm 200a, the reinforcing annular body 200b, and the auxiliary shaft 200c, one in which the diaphragm 200a, the reinforcing annular body 200b, and the auxiliary shaft 200c are each formed as a separate component is prepared. As described above, since the diaphragm 200a is formed as a separate component, the diaphragm 200a can be formed as a convenient diaphragm that is not limited in use.

  In the first embodiment, the diaphragm 200a is prepared by PFA and formed by extrusion molding. Extrusion by the extrusion method is performed, for example, as follows.

  The pelletized PFA prepared in advance is heated and melted by an extruder. Thereafter, the heated and melted PFA is pressed into a film-shaped cavity in a mold and gradually cooled to form a film. The molded product thus formed is punched into a disk shape corresponding to the diaphragm 200a. As a result, the diaphragm 200a is formed as a film-shaped diaphragm.

  As described above, the extrusion molding method using PFA was employed in forming the diaphragm 200a 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 liquid chamber Ra of the diaphragm valve, particles, for example, minute particles having a size of several nanometers, due to the cut marks of the diaphragm, are very small. If the particles come off from the diaphragm and generate dust and enter the liquid, the liquid 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 diaphragm 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. is there.

  Therefore, in the first embodiment, the diaphragm 200a is formed into a film shape by molding by an extrusion molding method. 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.

  Laser welding between the auxiliary shaft 200c and the central portion 240 of the diaphragm 200a is performed as follows. First, in the auxiliary shaft holding step S1 shown in FIG. 2, the auxiliary shaft 200c is held so that the female screw hole 260 is opened downward as shown in FIG. At this time, the holding is performed so that the female screw hole 260 is vertically positioned on the axis.

  Thereafter, in the diaphragm mounting step S2, the diaphragm 200a is mounted on the auxiliary shaft 200c so as to be located on the lower surface of the lower portion of the auxiliary shaft 200c at the center 240 (see FIG. 3). .

  Next, in the pressing plate mounting step S3, the pressing plate Q is mounted on the central portion 240 so as to coaxially oppose the auxiliary shaft 200c via the central portion 240 of the diaphragm 200a.

  Here, the holding plate Q is made of glass that easily transmits laser light, and is formed in a disk shape so as to have a predetermined thickness and a predetermined outer diameter. The glass that easily transmits the laser light has high thermal conductivity. Note that the pressing plate Q generally needs only to be a pressing member having light transmittance and heat conductivity, and the pressing member has any shape regardless of whether it is plate-shaped or not. It may be.

  As described above, since the holding plate Q is a glass that easily transmits laser light as described above, the holding plate Q does not easily absorb laser light. Further, since the above-mentioned glass forming the holding plate Q has high thermal conductivity, it easily absorbs the heat of the central portion 240 of the diaphragm 200a in a state where the glass is placed on the central portion 240 of the diaphragm 200a. In the first embodiment, the predetermined outer diameter of the holding plate Q is set to be larger than the outer diameter of the auxiliary shaft 200c.

  The predetermined thickness of the holding plate Q is selected as follows. In a state where the holding plate Q is placed on the center portion 240 of the diaphragm 200a as described above, a laser beam is passed through the holding plate Q and the boundary between the center portion 240 of the diaphragm 200a and the auxiliary shaft 200c as described later. When converged to the vicinity of the surface, the laser light is transmitted well through the holding plate Q, and the holding plate Q absorbs heat generated in the central portion 240 of the diaphragm 200a due to the laser light, thereby It is selected so that the temperature rise of the central portion 240 of the diaphragm 220 is suppressed well.

  After the holding plate Q is placed on the central portion 240 of the diaphragm 200a as described above, in the next holding step S4 for the holding plate, the holding plate Q is pressed from above by a suitable press machine (not shown). As a result, as shown by an arrow P in FIG. 3, the diaphragm 200a is pressed toward the central portion 240 of the diaphragm 200a. At this time, the pressing plate Q is pressed with a uniform pressing force over the entire upper surface of the central portion 240 of the diaphragm 200a on the lower surface thereof.

  In such a pressing state, in the next laser light irradiation step S5, laser light is irradiated toward the pressing plate Q by the laser device L (see FIG. 3) as follows.

  In the irradiation, the configuration of the laser device L will be described. The laser device L is configured to emit a laser beam at an emission unit. Here, the laser device is configured so that the laser light from the emission unit is converged by a lens system (not shown) on a focal point separated by a predetermined focal length from the lens system. Further, the laser device L is configured so that the emission intensity of the laser light from the emission part can be adjusted.

  When the laser device L irradiates the laser beam toward the holding plate Q, the laser device L is arranged so that the laser device L faces the outer peripheral portion of the central portion 240 of the diaphragm 200a at the emission portion. Is maintained directly above the outer peripheral portion of the central portion 240. In the first embodiment, the convergence point of the laser beam of the laser device L, that is, the focal point of the lens system is at the boundary between the outer peripheral portion of the central portion 240 of the diaphragm 200a and the corresponding portion of the auxiliary shaft 200c corresponding thereto. Hereinafter, it corresponds to the vicinity of a portion F (hereinafter, also referred to as an irradiation portion F) on a center portion-an auxiliary axis boundary portion (refer to FIG. 3).

  Here, the laser device L rotates around the axis of the holding plate Q while converging the laser light on the circumference including the vicinity of the irradiation portion F at the boundary between the central portion and the auxiliary axis and on the circumference. It has become.

  At this time, the height with respect to the outer peripheral portion of the central portion 240 of the diaphragm 200a of the laser device L is adjusted so that the focal point of the lens system of the laser device L coincides with the vicinity of the irradiation portion F at the boundary between the central portion and the auxiliary axis. Is adjusted.

  Furthermore, a portion including the central portion 240 of the diaphragm 200a and the lower surface portion a on the central side of the lower portion of the auxiliary shaft 200c is a circumferential region centered on the vicinity of the irradiation portion F at the boundary portion between the central portion and the auxiliary shaft ( The intensity of the laser light emitted from the laser device L is adjusted so that the laser beam can be melted in the melting region.

  Here, since the melting point of PFA is about 320 (° C.), the laser apparatus L uses the emission intensity to set the heating temperature for the vicinity of the irradiation portion F at the boundary between the central portion and the auxiliary axis to the melting point of PFA. It is set to be somewhat higher than that.

  However, in consideration of the fact that the holding plate Q absorbs the heat of the outer peripheral edge at the center of the diaphragm 200a due to its high thermal conductivity, the vicinity of the irradiation part F at the boundary between the center and the auxiliary shaft is considered. Even if the heating temperature with respect to the temperature rises above the melting point of PFA, the vicinity of the irradiation part F is set so that the melting region centered on the vicinity of the irradiation part F at the boundary between the central part and the auxiliary shaft falls within a predetermined region. Is set as a predetermined emission intensity.

  In other words, in the laser apparatus L, the irradiation intensity of the laser light irradiated along the melting region including the vicinity of the irradiation portion F at the boundary between the central portion and the auxiliary axis uniformly becomes the predetermined irradiation intensity. It is set as follows. In addition, the above-mentioned predetermined area, for example, in the state where the central portion 240 of the diaphragm 200a is mounted on the auxiliary shaft 200c, does not include at least the upper surface portion of the central portion 240 of the diaphragm 200a, and It refers to a region that does not include a part other than the part that includes the central lower surface part a.

  When the laser device L emits a laser beam as shown in FIG. 3 with its operation, the laser beam is applied to the outer peripheral edge of the holding plate Q and the diaphragm 200a as shown in FIG. The light passes through the outer peripheral edge of the central portion 240 in the thickness direction and converges to the vicinity of the irradiation portion F at the boundary between the central portion and the auxiliary shaft, which is sequentially displaced in the circumferential direction.

  Therefore, while the irradiation by the laser light is maintained, the lower surface of the central portion 240 of the diaphragm 200a and the lower portion of the lower portion of the auxiliary shaft 200c under the setting of the emission intensity of the laser light of the laser device L as described above. The portion including the portion a is sequentially heated by the laser light in accordance with the moving position of the laser device L locally along the circumferential direction of the boundary between the central portion and the auxiliary axis and around the vicinity of the irradiation portion F. . Along with this, the outer peripheral edge of the central portion 240 of the diaphragm 200a and the corresponding portion of the auxiliary shaft 200c with respect to the peripheral portion extend along the circumferential direction, centering on the vicinity of the irradiation portion F at the boundary between the central portion and the auxiliary shaft. It is locally and sequentially melted.

  In the first embodiment, in the above-described local heating, the heating temperature of the central portion 240 of the diaphragm 200a is reduced by the lower surface (the auxiliary shaft) of the central portion 240 of the diaphragm 200a under the heat absorbing action of the pressing plate Q. The surface of the auxiliary shaft 200c gradually decreases from the central portion 240 of the diaphragm 200a in the direction opposite to the upper surface of the central portion 240. Therefore, the auxiliary shaft 200c and the central portion 240 of the diaphragm 200a melt together in the above-described predetermined region.

  While maintaining the irradiation by the laser light, the laser apparatus L is rotated so as to sequentially converge the laser light along the circumference including the vicinity of the irradiation part F at the center-auxiliary axis boundary. I will do it.

  As a result, the portion including the central lower surface portion a of the lower portion of the auxiliary shaft 200c and the central portion 240 of the diaphragm 200a are centered on the molten region including the vicinity of the irradiation portion F at the boundary between the central portion and the auxiliary shaft. Over the above-mentioned predetermined area, it is heated by the laser beam and uniformly melted and welded together. Thereafter, by stopping the emission of the laser beam from the laser device L, the portion of the lower portion of the auxiliary shaft 200c including the lower surface a on the central side and the central portion 240 of the diaphragm 200a harden through natural cooling.

  Here, as described above, at least the upper surface portion of the central portion 240 of the diaphragm 200a is located in the lower portion of the central portion 240 of the diaphragm 200a in the portion including the central lower surface portion a in the lower portion of the auxiliary shaft 200c. In addition, since the lower portion of the auxiliary shaft 200c does not include a portion other than the portion including the central lower surface portion a, the central portion 240 of the diaphragm 200a is a portion of the lower portion of the auxiliary shaft 200c that includes the central lower surface portion a. The central portion 240 of the diaphragm 200a does not melt up to the joint surface with the pressing plate Q when it is placed on the support shaft 200c, and the portion of the lower portion of the auxiliary shaft 200c that includes the central lower surface portion a is There is no melting of the auxiliary shaft 200c to other parts. Therefore, the auxiliary shaft 200c and the diaphragm 200a can be welded to each other while maintaining their original shapes.

  Thereafter, in the pressing plate removing step S6 in FIG. 2, the pressing plate Q is removed from the central portion 240 of the diaphragm 200a. With this, in a state where the auxiliary shaft 200c and the central portion 240 of the diaphragm 200a are mutually weld-hardened, a connection configuration is formed by integrally joining the auxiliary shaft 200c and the central portion of the diaphragm 200a by laser welding.

  According to the above, the auxiliary shaft 200c and the center part of the diaphragm 200a can be satisfactorily joined and connected while ensuring convenience before laser welding as a single part of the diaphragm 200a. Along with this, the seal inside the liquid chamber Ra is satisfactorily based on the integral configuration of the outer peripheral portion 210, the central portion 240, and the curved displacement portion that is a portion between the outer peripheral portion 210 and the central portion 240 in the diaphragm 200a. Can be secured.

  Laser welding between the outer peripheral portion 210 of the diaphragm 200a and the reinforcing annular body 200b is performed as follows.

  After the integrated connection configuration by laser welding between the auxiliary shaft 200c and the central part of the diaphragm 200a is formed as described above, in the reinforcing annular body holding step S1a shown in FIG. 4, the reinforcing annular body 200c is It is held horizontally on its upper surface (see FIG. 5).

  Thereafter, in the diaphragm mounting step S2a, the diaphragm 200a is mounted on the reinforcing annular body 200b so as to be positioned on the reinforcing annular body 200b at the outer peripheral portion 210 (see FIG. 5). .

  Next, in the placing step S3a of the annular holding plate, the annular holding plate Q1 is placed on the outer peripheral portion 210 of the diaphragm 200a so as to coaxially oppose the reinforcing annular member 200b via the outer peripheral portion 210 of the diaphragm 200a. (See FIG. 5).

  Here, the annular pressing plate Q1 is formed in the shape of a ring so as to have a predetermined thickness and a predetermined outer inner diameter with the same material as the material forming the pressing plate Q. Therefore, the annular holding plate Q1 has the same characteristics as the holding plate Q, that is, light transmittance and high thermal conductivity.

  Therefore, the annular pressing plate Q1 hardly absorbs laser light due to its light transmittance. Further, due to the high thermal conductivity, the annular pressing plate Q1 easily absorbs heat of the outer peripheral portion 210 of the diaphragm 200a in a state of being placed on the outer peripheral portion 210 of the diaphragm 200a.

  The predetermined thickness of the annular holding plate Q1 is such that the laser light is applied to the annular holding plate Q1 while the annular holding plate Q1 is placed on the outer peripheral portion 210 of the diaphragm 200a as described above. When the laser beam converges near the boundary between the outer peripheral portion 210 of the diaphragm 200a and the reinforcing annular body 200b, the laser light satisfactorily passes through the annular pressing plate Q1, and the annular pressing plate Q1 is caused by the laser light. Then, heat generated in the outer peripheral portion 210 of the diaphragm 200a is absorbed, and the temperature rise of the outer peripheral portion 210 of the diaphragm 220 is appropriately suppressed. The predetermined outer diameter of the annular pressing plate Q1 is larger than the outer diameter of the reinforcing annular body 200b, and the predetermined inner diameter of the annular pressing plate Q1 is selected to be smaller than the inner diameter of the reinforcing annular body 200b.

  After the annular pressing plate Q1 is placed on the outer peripheral portion 210 of the diaphragm 200a as described above, in the next pressing step S4a for the annular pressing plate, the annular pressing plate Q1 is pressed from above by a suitable pressing machine ( (Not shown), as shown by an arrow P1 in FIG. 5, is pressed against the outer peripheral portion 210 of the diaphragm 200a. At this time, the annular pressing plate Q1 is pressed with a uniform pressing force over the entire upper surface of the outer peripheral portion 210 of the diaphragm 200a on the lower surface thereof.

  In such a pressing state, in the next laser light irradiation step S5a, laser light is irradiated toward the annular pressing plate Q1 by the laser device L (see FIG. 6) as described below. .

  When irradiating the laser beam toward the annular holding plate Q1 with the laser device L, the outer peripheral portion 20 of the diaphragm 200a is positioned so that the laser device L faces the outer peripheral portion 210 of the diaphragm 200a at its emission portion. Maintained directly above. In the first embodiment, the convergence point of the laser beam of the laser device L, that is, the focal point of the lens system is set at the boundary between the outer peripheral portion 210 of the diaphragm 200a and the reinforcing annular body 200b (hereinafter, the outer peripheral portion). -It corresponds to the vicinity of a part F1 (hereinafter also referred to as an irradiation part F1) on the boundary between the reinforcing annular bodies (refer to FIG. 5).

  Here, the laser device L is arranged along the circumference including the vicinity of the irradiation site F1 at the boundary between the outer peripheral portion and the reinforcing annular body, and converges the laser beam on the circumference while converging the laser light on the circumference. It is designed to rotate.

  At this time, the height of the diaphragm 200a of the laser device L with respect to the outer peripheral portion 210 is set such that the focal point of the lens system of the laser device L is in the vicinity of the irradiation portion F1 at the boundary between the outer peripheral portion and the reinforcing annular body. The position is adjusted.

  Further, the laser device L is arranged so that the outer peripheral portion 210 of the diaphragm 200a and the upper surface side portion of the reinforcing annular body 200b can be melted around the irradiation area F1 at the boundary between the outer peripheral portion and the reinforcing annular body. The emission intensity of the laser light from the laser is adjusted.

  Specifically, the laser device L is configured so that, at its emission intensity, the heating temperature for the vicinity of the irradiation site F1 at the boundary between the outer peripheral portion and the reinforcing annular body is slightly higher than the melting point of PFA. Is set.

  However, in consideration of the fact that the annular pressing plate Q1 absorbs heat of the outer peripheral portion 210 of the diaphragm 200a due to its high thermal conductivity, the vicinity of the irradiation portion F1 at the boundary between the outer peripheral portion and the reinforcing annular member is considered. Even if the heating temperature with respect to the temperature rises above the melting point of PFA, the melting region centering on the vicinity of the irradiation site F1 at the boundary between the outer peripheral portion and the reinforcing annular body is the same as in the case of the holding plate Q. The emission intensity of the laser light with respect to the vicinity of the irradiation site F1 is set as a predetermined emission intensity so as to fall within the region.

  Then, when the laser device L emits a laser beam due to the rotation operation, the laser beam causes the annular pressing plate Q1 and the outer peripheral portion 210 of the diaphragm 200a to move in the respective thickness directions as shown in FIG. The light passes through and converges to the vicinity of the irradiation portion F1 at the boundary between the outer peripheral portion and the reinforcing annular body which is sequentially displaced.

  Therefore, while maintaining the irradiation by the laser light, the outer peripheral part 210 of the diaphragm 200a and the upper surface side part of the reinforcing annular body 200b are set under the setting of the emission intensity of the laser light of the laser device L as described above. The laser device L is sequentially heated by the laser light along the circumferential direction of the boundary between the outer peripheral portion and the reinforcing annular member and locally in the vicinity of the irradiation portion F1 in accordance with the moving position of the laser device L. Along with this, the outer peripheral portion 210 of the diaphragm 200a and the upper surface side portion of the reinforcing annular body 200b extend along the circumferential direction, and are locally centered around the irradiation site F1 at the boundary between the outer peripheral portion and the reinforcing annular body. And are sequentially melted.

  In the first embodiment, in the above-described local heating, the heating temperature of the outer peripheral portion 210 of the diaphragm 200a is reduced by the lower end (reinforcement) of the outer peripheral portion 210 of the diaphragm 200a under the heat absorbing action of the annular pressing plate Q1. From the side of the annular body 200b) to the surface on the opposite side, and in the reinforcing annular body 200b, from the outer peripheral portion 210 side of the diaphragm 200a in the direction opposite to the upper surface of the outer peripheral portion 210. And gradually decrease. Accordingly, the outer peripheral portion 210 of the reinforcing annular body 200b and the diaphragm 200a are melted together in the above-described predetermined region.

  While maintaining the irradiation by the laser light, the laser device L applies the laser light along a circumferential area (melted area) including the vicinity of the irradiation part F1 at the boundary between the outer peripheral part and the reinforcing annular body. Rotate so as to converge sequentially.

  As a result, the upper surface side portion of the reinforcing annular body 200b and the outer peripheral portion 210 of the diaphragm 200a are aligned with the above-described predetermined region centering on a circumferential region including the vicinity of the irradiation site F1 at the boundary between the outer peripheral portion and the reinforcing annular body. Heated by the laser beam over the region, it is uniformly melted and welded together. Thereafter, by stopping the emission of the laser beam from the laser device L, the upper surface side portion of the reinforcing annular body 200b and the outer peripheral portion 210 of the diaphragm 200a harden through natural cooling. Therefore, the reinforcing annular body 200b and the diaphragm 200a can be welded to each other while maintaining their original shapes.

  Thereafter, in the annular holding plate removing step S6a in FIG. 4, the annular holding plate Q1 is removed from the outer peripheral portion 210 of the diaphragm 200a. Thus, in a state where the outer peripheral portion 210 of the reinforcing annular body 200b and the outer peripheral portion 210 of the diaphragm 200a are mutually weld-hardened, an integrated joining configuration by laser welding of the outer peripheral portion of the reinforcing annular body 200b and the outer peripheral portion of the diaphragm 200a is formed. You. Accordingly, a good seal can be secured between the reinforcing annular body 200b and the outer peripheral portion 210 of the diaphragm 200a.

  As described above, the diaphragm member 200 is integrally formed with the diaphragm 200a, the reinforcing annular body 200b, and the holding shaft 200c. The auxiliary shaft 200c of the diaphragm member 200a thus configured is formed as a separate component from the piston shaft 320 of the drive mechanism 300. Therefore, according to the diaphragm member 200, it is possible to easily assemble the components such as the partition wall 120 between the drive mechanism 300 and the diaphragm 200a in the housing 100, and at least the diaphragm before the laser welding. The convenience that the member 200 can be used also in a diaphragm valve having various specifications can be ensured.

  After the diaphragm member 200 is formed as described above, the diaphragm member 200 holds the auxiliary shaft 200c on the upper side, and the diaphragm 200a uses the upper wall 111 of the bottom wall 110 prepared in advance. It fits inside the outer annular wall 111b and is seated on the inner annular wall 111a via the reinforcing annular body 200b.

  At this time, since the reinforcing annular body 200b is laser-welded to the outer peripheral portion of the diaphragm 200a, the reinforcing annular body 200b is connected to the inner annular wall inside the outer annular wall 111b of the upper wall 111 of the bottom wall 110. By sitting on the portion 111a, the diaphragm 200a can be seated on the inner annular wall portion 111a via the reinforcing annular body 200b.

  In other words, even if it is difficult to handle the diaphragm 200a because it is thin, the reinforcing annular body 200b is formed by the welding configuration of the outer peripheral portion 210 of the diaphragm 200a and the reinforcing annular body 200b by the laser welding as described above. Thus, the diaphragm 200a can be easily fitted inside the outer annular wall portion 111b of the upper wall portion 111, and can be seated on the inner annular wall portion 111a together with the reinforcing annular body 200b.

  Next, as shown in FIG. 1, the partition wall 120 faces the inner annular wall portion 111a via the diaphragm 200a at the partition body 120a so that the partition wall 120 faces the diaphragm 200a at the inner end opening of the communication passage 121. Is fitted inside the outer annular wall portion 111b, and is assembled to the bottom wall 110 at the annular flange portion 120b so as to be seated on the outer annular wall portion 111b. Accordingly, the outer peripheral portion 210 of the diaphragm 200a is separated from the outer peripheral portion 210 of the diaphragm 200a by the laser welding of the outer peripheral portion 210 of the diaphragm 200 with the reinforcing annular member 200b via the reinforcing annular member 200b. As described above, the seal inside the liquid chamber Ra can be satisfactorily ensured as described above. As described above, when the partition wall 120 is assembled to the upper wall 110, the partition wall 120 is coaxially fitted to the auxiliary shaft 200c at the through hole 122 thereof.

  Next, the piston shaft 320 is coaxially fastened into the female screw hole 260 of the auxiliary shaft 200c while being fitted into the through hole 122 of the partition wall 120 via the O-ring 321 at the axial male screw portion 320b. You. At this time, as described above, the central portion 240 of the diaphragm 200a and the extended end of the auxiliary shaft 200c are joined by laser welding. Therefore, although the above-mentioned film-shaped diaphragm 200a is very thin, since the diaphragm 200a is joined to the auxiliary shaft 200c by laser welding at the central portion 240, the diaphragm 200a is connected to the piston shaft 320 at the central portion. Even if it does not have a connecting portion required for connection of the piston shaft 320, the shaft-like external thread portion 320b of the piston shaft 320 is screwed into the female screw hole portion 260 of the auxiliary shaft 200c, so that the piston shaft 320, the diaphragm 200a and the auxiliary shaft 200c can be connected. Can be easily connected.

  Thereafter, the upper housing member 100b accommodates the piston 310 in the hollow portion 131 of the peripheral wall 130 via the O-ring 131 while the coil spring 330 prepared in advance is fitted in the annular groove portion 141, and the distal end thereof is At the opening, it is fitted on the partition main body 120a and sits on the annular flange 120b. Thereby, the manufacture and assembly of the diaphragm valve are completed.

  In the first embodiment configured as described above, it is assumed that the pneumatically actuated diaphragm valve is in a closed state when a semiconductor element is manufactured by the semiconductor manufacturing apparatus.

  At this time, in the air-operated diaphragm valve, the piston 310 slides downward in the upper housing member 110b based on the urging force of the coil spring 330.

  Accordingly, the piston shaft 320 causes the diaphragm 200a to be seated on the annular valve seat portion 111c at the valve body portion 240, which is the central portion 240, via the auxiliary shaft 200c. In such a closed state of the diaphragm valve, when the compressed air flow is supplied from the compressed air flow supply source through the opening 134 and the communication passage 133 of the upper housing member 100b into the lower chamber 131b, the piston 310 is moved. However, together with the piston shaft 320, the hollow 131 of the upper housing member 100b slides upward against the urging force of the coil spring 330 based on the pressure of the compressed air flow in the lower chamber 131b.

  Along with this, the auxiliary shaft 200c cooperates with the piston shaft 320, and the diaphragm 200a is pulled by the auxiliary shaft 200c at the central portion 240 thereof, and is displaced in a curved shape toward the air chamber Rb. Accordingly, the diaphragm 200a is separated from the annular valve seat 111c at the center 240 thereof. As a result, the diaphragm valve is opened.

  In such a state, when the liquid is supplied from the liquid supply source to the upstream portion of the piping system, the liquid passes through the inflow cylinder 110b, the communication passage portion 112, and the annular valve seat portion 111c and enters the liquid chamber Ra. Inflow. As described above, the liquid flowing into the liquid chamber Ra flows out into the downstream portion of the piping system through the communication path 113 and the outflow tube 110c.

  In such a flow process of the liquid, as described above, the liquid flowing into the liquid chamber Ra causes the diaphragm 200a to bend and displace to the air chamber Rb side or the liquid chamber Ra according to the fluctuation of the liquid pressure. The liquid flows from the liquid chamber Ra into the outflow cylinder 110c through the communication path 113.

  Here, the diaphragm 200a is a film-shaped diaphragm formed by extrusion molding with PFA, as described above. Therefore, the diaphragm 200a has a good smooth surface on both surfaces.

  Therefore, even when the diaphragm valve is in the operating state, it is needless to say that particles caused by cutting marks are not separated from the diaphragm 200a due to contact with the liquid of the diaphragm 200a and mixed into the liquid. That is, even the incorporation of minute particles having a size of several nanometers into the liquid can be suppressed to the minimum (minimum). This is also true when the central portion 240 of the diaphragm 200a is seated on or separated from the annular valve seat 111c in the operating state of the diaphragm valve.

  From the above, the liquid flowing into the liquid chamber Ra is kept substantially clean by minimizing even the incorporation of fine particles having a size of several nm, and is thus kept substantially clean. It flows out into the downstream part of the piping system through the outflow tube 110c.

  Therefore, even when the liquid flowing out into the downstream portion of the piping system flows along the surface of a semiconductor wafer having a wiring pitch of, for example, 10 (nm) or less, in manufacturing a semiconductor device, particles having a size of several nm are generated. It 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.

  Further, as described above, since the film-like diaphragm 200a is formed by extrusion molding using PFA, the generation of particles of several nm in size can be suppressed to a minimum and the bendability is excellent and the long life is maintained. Can be formed as a diaphragm that can be used. Therefore, even if a diaphragm valve having such a diaphragm 200a is applied to a semiconductor manufacturing apparatus, the diaphragm 200a maintains the bending operation satisfactorily for a long period of time, so that the diaphragm valve is applied to a semiconductor manufacturing apparatus. As a valve, good function can be maintained for a long time.

(2nd Embodiment)
FIG. 6 shows a main part of the second embodiment of the present invention. In the second embodiment, the diaphragm member formed by laser-welding the reinforcing annular body 200b to the outer peripheral portion 210 of the diaphragm 200a from the upper surface side of the diaphragm member described in the first embodiment is used as the air-operated diaphragm valve. This is adopted in place of the member 200. In addition, the diaphragm member referred to in the second embodiment is also denoted by the reference numeral 200, similarly to the first embodiment.

  The diaphragm member 200 includes a diaphragm 200a, an annular reinforcing member 200b, and an auxiliary shaft 200c, as in the first embodiment. Also in the second embodiment, the auxiliary shaft 200c is laser-welded to the central portion 240 of the diaphragm 200a, as in the first embodiment. Further, unlike the first embodiment, the reinforcing annular body 200b is laser-welded from the upper surface 230 side at the outer peripheral portion 210 of the diaphragm 200a.

  Here, the laser welding of the outer peripheral portion 210 of the diaphragm 200a formed by laser welding to the auxiliary shaft 200c and the reinforcing annular body 200b as in the first embodiment is performed as follows.

  In the holding step S1a of the reinforcing annular body of FIG. 4, the reinforcing annular body 200b is held so as to be positioned horizontally on the upper surface thereof (see FIG. 7). Then, in the next diaphragm mounting step S2a, unlike the first embodiment, the diaphragm 200a is mounted on the reinforcing annular body 200b from above on the upper surface 230 thereof. At this time, the mounting is performed such that the outer peripheral portion 210 of the diaphragm 200a coaxially corresponds to the reinforcing annular body 200b.

  After that, the processes of placing the annular press plate S3a, irradiating the laser beam S5a, and removing the annular press plate S6a are performed in the same manner as in the first embodiment. Thus, in a state where the outer peripheral portion 210 of the reinforcing annular body 200b and the outer peripheral portion 210 of the diaphragm 200a are mutually weld-hardened, an integrated joining configuration by laser welding of the outer peripheral portion of the reinforcing annular body 200b and the outer peripheral portion of the diaphragm 200a is formed. You.

  As a result, with respect to laser welding between the reinforcing annular body 200b and the outer peripheral portion of the diaphragm 200a, the same operation and effect as described in the first embodiment are obtained while securing the convenience of the diaphragm 200a. This can also be achieved in the diaphragm member 200 of FIG.

  As described above, after the diaphragm member 200 according to the second embodiment is formed, the diaphragm member 200 is assembled to the lower housing member 100a as follows.

  Here, in the bottom wall main body 110a of the lower housing member 100a described in the first embodiment, the upper wall portion 111 includes, in addition to the inner annular wall portion 111a and the outer annular wall portion 111b, these inner annular wall portions 111a and 111b. It is formed so as to have a middle wall portion 111d between the portion 111a and the outer annular wall portion 111b.

  Here, the middle wall portion 111d is formed on the outer peripheral portion of the inner annular wall portion 111a, and the middle wall portion 111d protrudes higher than the inner annular wall portion 111a. As a result, the bottom wall main body 111 is formed so as to protrude upward in the upper wall portion 111 sequentially over the inner annular wall portion 111a, the middle wall portion 111d, and the outer annular wall portion 111b.

  Thus, in the second embodiment, in the diaphragm member 200 configured as described above, the diaphragm 200a is fitted in the outer wall portion 211a in a state where the reinforcing annular body 200b is positioned on the upper side. Then, the user sits on the inner wall portion 111d at the outer peripheral portion 210. Accordingly, the reinforcing annular body 200b is fitted into the outer annular wall 111b from above the diaphragm 200a.

  Next, as shown in FIG. 6, the outer annular wall portion is formed on the partition body 120 a via the reinforcing annular body 200 b so as to face the diaphragm 200 a at the inner end opening of the communication passage 121. It is fitted to the inside of 111b and is seated on the reinforcing annular body 200b, and is assembled to the bottom wall 110 so as to be seated on the outer annular wall 111b by the annular flange 120b. At this time, the auxiliary shaft 200c is coaxially slidably fitted in the through hole 122 of the partition wall 120.

  As described above, unlike the first embodiment, even when the diaphragm member 200 has a configuration in which the reinforcing annular body 200b is laser-welded to the outer peripheral portion 210 of the diaphragm 200a from the upper surface side, the auxiliary shaft 200c is not used. , Are formed as separate components from the piston shaft 320 of the drive mechanism 300. Therefore, also in the second embodiment, according to the diaphragm member 200, it is needless to say that the components such as the partition wall 120 and the like between the drive mechanism 300 and the diaphragm 200a can be easily assembled in the housing 100. Thus, the convenience that the diaphragm member 200 can be used in a diaphragm valve having various specifications can be secured.

  Next, the piston shaft 320 is coaxially fastened into the female screw hole 260 of the auxiliary shaft 200c while being fitted into the through hole 122 of the partition wall 120 via the O-ring 321 at the axial male screw portion 320b. You. Thus, as described in the first embodiment, even if the diaphragm 200a does not have a connection portion required for connection with the piston shaft 320 at the center thereof, the inside of the female screw hole portion 260 of the auxiliary shaft 200c can be formed. By fastening the male screw portion 320b of the piston shaft 320 to the piston shaft 320, the connection between the diaphragm 200a and the piston shaft 320 can be easily performed. The other configuration and operation and effect are the same as those of the first embodiment.

(Third embodiment)
FIG. 8 shows a third embodiment of the diaphragm valve to which the present invention is applied. In the third embodiment, an electromagnetically actuated diaphragm valve is employed as the diaphragm valve, unlike the air actuated diaphragm valve described in the first embodiment.

  As shown in FIG. 8, the electromagnetically actuated diaphragm valve includes a cylindrical housing, the diaphragm member 200 described in the first embodiment, and an electromagnetically actuated drive mechanism 400, and is a normally closed electromagnetic valve. It is configured as an actuated solenoid valve. In the third embodiment, the cylindrical housing is denoted by reference numeral 100, as in the first embodiment. In addition, the electromagnetically driven drive mechanism 400 is hereinafter also referred to as a drive mechanism 400.

  The cylindrical housing 100 according to the third embodiment includes a lower housing member 100c and an upper housing member 100d. As shown in FIG. 8, the lower housing member 100c includes the bottom wall 110 and the partition wall 150 described in the first embodiment.

  As shown in FIG. 8, the partition 150 has a partition main body 150a and an annular flange 150b, and the partition main body 150a has an outer annular wall at the lower wall of the upper wall 111 of the bottom wall main 110a. It is fitted in the portion 111b and is seated on the inner annular wall portion 111a via the diaphragm 200a of the diaphragm member 200 and the reinforcing annular body 200b.

  Further, the annular flange 150b is formed so as to project annularly radially outward from a portion of the outer peripheral portion of the partition wall main body 150a other than the lower portion, and the annular flange 150b is formed in the bottom wall main body 110a. Is coaxially seated on the outer annular wall portion 111b of the upper wall portion 111. In this manner, the partition 150 is coaxially assembled to the bottom wall main body 110a from above through the diaphragm 200a and the reinforcing annular body 200b.

  The upper housing member 100d is formed in a rectangular cross section similarly to the upper housing member 100b described in the first embodiment, and the upper housing member 100d has a peripheral wall 170 and an upper wall 180, It is integrally formed of a magnetic material (for example, iron).

  The peripheral wall 170 extends downwardly from the upper wall 180 in a cylindrical shape, and the peripheral wall 170 extends above the partition wall 150 together with an annular flange portion 160b (described later) of the guide member 160 at an extension end opening thereof. Is mounted coaxially.

  The guide member 160 plays a role of guiding the plunger 400b (described later) in the axial direction, and the guide member 160 is formed so as to integrally have the cylindrical portion 160a and the annular flange portion 160b. . The annular flange portion 160b extends in a radial direction from the lower end portion of the cylindrical portion 160a so as to be parallel to the upper wall 180 so that the circular head portion 160a is coaxially positioned in the peripheral wall 170. The annular flange portion 160b is fixed by caulking at the outer peripheral portion thereof to the extension end opening of the peripheral wall 170. The cylindrical portion 160a extends coaxially from the inner peripheral portion of the annular flange portion 160b into the peripheral wall 170.

  The diaphragm member 200 has a configuration similar to that of the diaphragm member described in the first embodiment. In the diaphragm member 200, the diaphragm 200a includes the upper wall portion of the bottom wall main body 110a together with the reinforcing annular body 200b. 111 is fitted on the inner peripheral side of the outer annular wall portion 111b.

  Along with this, the diaphragm 200a is seated on the inner annular wall 111a of the upper wall 111 via the reinforcing annular body 200b, and the diaphragm 200a is formed on the inner peripheral side of the outer annular wall 111b. The space between the wall 111a and the partition main body 150a is partitioned into the liquid chamber Ra and the air chamber Rb described in the first embodiment.

  The auxiliary shaft 200c is slidably fitted in a through hole 151 formed coaxially with the center of the partition wall main body 150a. The above-described air chamber Rb may be opened to the outside through the partition 150 inside the inside, or the inside of the upper housing member 100d through the space between the through hole 151 of the partition main body 150a and the auxiliary shaft 200c. May be communicated with.

  The drive mechanism 400 includes a coil member 400a, a plunger 400b, a coil spring 400c, and a columnar stopper member 400d. The coil member 400a is coaxially fitted in the peripheral wall 170 of the upper housing member 100d. The coil member 400a has a cylindrical bobbin 410 and a solenoid 420. The tubular bobbin 410 includes a tubular portion 411 and upper and lower annular walls 412 and 413 extending radially outward from both axial ends of the tubular portion 411. The solenoid 420 is wound around the cylindrical portion 411 between the upper and lower annular walls 412 and 413.

  The coil member 400a thus configured is housed in the peripheral wall 170 so as to be fitted to the cylindrical portion 160a of the guide member 160 and the cylindrical stopper member 400d at the cylindrical portion 411 of the cylindrical bobbin 410. ing. The solenoid 420 is connected at its upper end terminal to a power supply line H of a power supply (not shown) via an upper annular wall 412 of the cylindrical bobbin 410.

  In the thus configured coil member 400a, when the solenoid 420 is energized by receiving power from the power supply via the power supply line H, the solenoid 420 generates a magnetic attractive force. When the solenoid 420 is cut off from the power supply, the solenoid 420 is demagnetized and stops generating magnetic attraction.

  The plunger 400b is made of a magnetic material. The plunger 400b includes a cylindrical plunger main body 430 and a male screw shaft 440. The plunger main body 430 is a cylindrical part of the guide member 160. 160a is slidably fitted coaxially. The male screw shaft portion 440 extends coaxially downward from the lower end of the plunger body 430, and the male screw shaft portion 440 is fastened in the female screw hole 260 of the auxiliary shaft 200c.

  The coil spring 400c is inserted into an insertion hole 431 formed coaxially from the upper end of the plunger body 430 of the plunger 400b. Further, the stopper member 400d is coaxially fixed to the center of the upper wall 180 in the upper housing member 100d, and the cylindrical portion 160a of the guide member 160, the plunger body 430 of the plunger 400b, and the coil spring 400c. Extending toward.

  As a result, the coil spring 400c is sandwiched between the center of the extended end of the stopper member 400d and the bottom of the insertion hole 431 of the plunger body 430, and attaches the plunger 400b toward the auxiliary shaft 200c. Energize.

  Thus, in the drive mechanism 400, when the solenoid 420 generates a magnetic attraction, the plunger 400b moves toward the stopper member 400d based on the magnetic attraction against the urging force of the coil spring 400c. The diaphragm 200a is sucked and slid along the cylindrical portion 160a of the guide member 160 toward the extending end of the stopper member 400d, so that the diaphragm 200a is separated from the annular valve seat portion 111c via the auxiliary shaft 200c by the male screw shaft portion 440. Displace in a curved shape.

  On the other hand, when the generation of the magnetic attractive force of the solenoid 420 is stopped, the plunger 400b slides toward the partition 150 under the urging force of the coil spring 400c, and the auxiliary shaft 200c is moved by the male screw shaft portion 440. The diaphragm 200a is displaced in a curved shape so as to be seated on the annular valve seat 111c through the intermediary of the diaphragm 200a. Other configurations are the same as those in the first embodiment.

  In the third embodiment configured as described above, the electromagnetically actuated diaphragm valve is employed as a diaphragm valve in place of the pneumatically actuated diaphragm valve described in the first embodiment.

  According to this, the electromagnetically actuated diaphragm valve according to the third embodiment is different from the pneumatically actuated drive mechanism 300 and the upper housing member 100b of the pneumatically actuated diaphragm valve described in the first embodiment. By having the member 100d and the electromagnetically actuated drive mechanism 400, although the shaft-shaped male screw portion 440 of the plunger 400b is fastened to the female screw hole 260 of the auxiliary shaft 200c, the diaphragm member 200 and the lower housing member 100a The second embodiment is substantially the same as the first embodiment except that the partition has a slightly different structure.

  Therefore, also in the third embodiment, since the central portion 240 of the diaphragm 200a has been laser-welded to the auxiliary shaft 200c as described above, the axial male screw portion 440 of the plunger 400b is connected to the female screw hole 260 of the auxiliary shaft 200c. , The plunger 400b, the diaphragm 200a, and the auxiliary shaft 200c can be easily connected.

  In the third embodiment, when the electromagnetically actuated diaphragm valve is interposed in the piping system of the semiconductor manufacturing apparatus instead of the pneumatically actuated diaphragm valve described in the first embodiment, a diaphragm member is provided. In the third embodiment, the operation of the diaphragm 200a and the auxiliary shaft 200c is performed not by the operation of the piston 310 by the compressed air in the first embodiment but by the operation of the plunger 400b by the magnetic attraction force. The opening / closing operation as the diaphragm valve and the configuration of the diaphragm member 200 are the same as those of the first embodiment, and the same operation and effects as those of the first embodiment can be achieved.

(Fourth embodiment)
FIG. 9 shows a fourth embodiment of the present invention. In the fourth embodiment, the electromagnetically actuated diaphragm valve employs the diaphragm member 200 (see FIGS. 6 and 7) and the lower housing member 100a described in the second embodiment, and the second embodiment. In place of the upper housing member 100b and the pneumatically driven drive mechanism 300 described above, the upper housing member 100d and the electromagnetically driven drive mechanism 400 described in the third embodiment are employed.

  Here, the auxiliary shaft 200c is slidably fitted into the through hole 151 of the partition 150 through the reinforcing annular body 200b, and the plunger 400b is inserted into the female screw hole 260 of the auxiliary shaft 200c. Male screw shaft portion 440 is fastened. In the fourth embodiment, the auxiliary shaft 200c and the male shaft 440 have a longer axial length than the auxiliary shaft 200c and the male male screw 440 of the third embodiment. 200b. Other configurations are the same as those of the second embodiment.

  In the fourth embodiment configured as described above, the electromagnetically actuated diaphragm valve is employed as a diaphragm valve in place of the pneumatically actuated diaphragm valve described in the second embodiment.

  According to this, the electromagnetically actuated diaphragm valve according to the fourth embodiment is different from the pneumatically actuated drive mechanism 300 and the upper housing member 100b of the pneumatically actuated diaphragm valve described in the second embodiment. By having the member 100d and the electromagnetically actuated drive mechanism 400, although it is fastened to the central portion 240 of the diaphragm 200a via the reinforcing annular body 200b by the axial male screw portion 440 of the plunger 400b, the diaphragm member 200 and the lower side The housing member 100a is substantially the same as the second embodiment, except that the partition has a slightly different configuration.

  Therefore, also in the fourth embodiment, since the central portion 240 of the diaphragm 200a has been laser-welded to the auxiliary shaft 200c as described above, the axial male screw portion 440 of the plunger 400b is connected to the female screw hole 260 of the auxiliary shaft 200c. , The plunger 400b, the diaphragm 200a, and the auxiliary shaft 200c can be easily connected.

  In the fourth embodiment, when the electromagnetically actuated diaphragm valve is interposed in the piping system of the semiconductor manufacturing apparatus instead of the air actuated diaphragm valve described in the second embodiment, the diaphragm member In the fourth embodiment, the operation of the diaphragm 200a and the auxiliary shaft 200c of the plunger 200 is not the operation of the piston 310 by the compressed air in the second embodiment, but is the plunger by the magnetic attraction force as in the third embodiment. Although the opening and closing operation as the diaphragm valve and the configuration of the diaphragm member 200 are the same as those of the second embodiment, the same operation and effects as those of the second embodiment can be 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 PFA into a film by extrusion, but may be formed by compressing PFA into a film. It may be a diaphragm formed by compression molding.

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

(2) In the embodiment of the present invention, the driving mechanism 300 described in the first or second embodiment is different from the above-described embodiment in that the coil spring 330 in FIG. , The piston 310 may be configured to be urged in a direction opposite to the partition wall 120. This means that the diaphragm valve functions as a normally-open diaphragm valve.

  As described above, even when the diaphragm valve described in the first or second embodiment is operated as a normally-open diaphragm valve, substantially the same operation as in the first or second embodiment is performed. The effect can be achieved.

(3) In the embodiment of the present invention, the driving mechanism 400 described in the third or fourth embodiment is different from the third or fourth embodiment in that the coil spring 400c in FIG. Alternatively, the plunger 400b may be provided so as to urge the stopper member 400d. This means that the electromagnetically actuated diaphragm valve functions as a normally open diaphragm valve.

  As described above, even when the electromagnetically actuated diaphragm valve described in the third or fourth embodiment operates as a normally open diaphragm valve, it is substantially the same as the third or fourth embodiment. A similar effect can be achieved.

(4) Further, in carrying out the present invention, the reinforcing annular body 200b may be eliminated as necessary. In this case, the outer peripheral portion 210 of the diaphragm 200a is sandwiched between the outer peripheral portion of the partition wall main body 120a of the partition wall 120 and the inner annular wall portion 111a of the bottom wall main body 110a so as to be able to seal well.

(5) In practicing the present invention, the piston shaft 320 described in the first embodiment has a female screw hole formed coaxially on the shaft body 320a from the extending end side instead of the male screw portion 320b. On the other hand, the female screw hole 260 may be eliminated by forming the auxiliary shaft 200c so that the axial male screw portion extends coaxially from the extending end thereof. In this case, the auxiliary shaft 200c is coaxially fastened to the female screw hole of the shaft main body portion 320a of the piston shaft 320 at the shaft-like male screw portion.

(6) In the embodiment of the present invention, the plunger 400b described in the third or fourth embodiment is provided on the plunger main body 430 at the extension end side instead of the axial male screw part 440. A female screw hole is formed coaxially, while the auxiliary shaft 200c is formed so that a shaft-like male screw portion extends coaxially from its extending end, thereby eliminating the female screw hole 260. Is also good. In this case, the auxiliary shaft 200c is coaxially fastened to the female screw hole of the plunger 400b at the axial male screw portion.

(7) In practicing the present invention, a ring-shaped holding plate that plays a role similar to that of the holding plate Q may be used instead of the holding plate Q. In general, the same shape as the holding plate Q is used. A holding member having a function may be used.

100: housing, 100a, 100c: lower housing member,
100b, 100d ... upper housing member, 110 ... bottom wall,
112, 113: communication passage portion, 110b: inflow cylinder, 110c: outflow cylinder,
111c: annular valve seat, 120, 150: partition, 130: cylindrical peripheral wall,
131a: upper chamber, 131b: lower chamber, 140: upper wall,
200: diaphragm member, 200a: diaphragm,
200b: annular ring for reinforcement, 200c: auxiliary shaft, 300: pneumatic drive mechanism,
310: piston, 320: piston shaft, 330, 400c: coil spring,
400: electromagnetically actuated diaphragm valve, 400b: plunger, Ra: liquid chamber,
Rb: air chamber, Q: holding plate, Q1: annular holding plate.

Claims (10)

A film diaphragm made of PFA applied to a diaphragm valve for flowing a liquid such as a high-purity chemical solution or ultrapure water;
A diaphragm member comprising a fluororesin auxiliary shaft joined coaxially to the center of the film diaphragm by laser welding.   2. The diaphragm member according to claim 1, further comprising a reinforcing annular member made of fluororesin, which is laser-welded to one of the two surfaces of the diaphragm along an outer peripheral portion thereof. 3.   3. The diaphragm member according to claim 1, wherein the diaphragm is formed in a film shape by extruding or compressing PFA. 4. The auxiliary shaft has an outer diameter within a range of 1 (mm) or more and 4 (mm) or less,
The diaphragm member according to claim 3, wherein the diaphragm has a thickness within a range of 0.1 (mm) or more and 0.5 (mm) or less. When the valve is opened, a liquid such as a high-purity chemical solution or ultrapure water flows from the inflow side to the outflow side, and when the valve is closed, the diaphragm valve shuts off the flow of the liquid,
A housing having a cylindrical peripheral wall and opposite walls formed on the cylindrical peripheral wall so as to oppose each other so as to close both axial openings thereof;
A partition wall provided at an axially intermediate portion of the cylindrical peripheral wall to partition a hollow portion of the cylindrical peripheral wall between one of the two opposing walls and the other opposing wall,
Driving means assembled between the one opposing wall and the partition in the hollow portion of the cylindrical peripheral wall,
A film diaphragm made of PFA, which is provided in the housing and forms a liquid chamber between the other facing wall and defines an inside of the housing so as to form an air chamber with the partition wall; A through-hole formed in the center of the diaphragm by a laser welding coaxially and extending from the center with a fluororesin auxiliary shaft formed in the partition wall in the axial direction with the auxiliary shaft; A diaphragm member fitted slidably in the part,
The drive means integrally includes a drive shaft coaxially connected to an extended end of the auxiliary shaft so as to be axially movable toward the air chamber or in the opposite direction together with the auxiliary shaft of the diaphragm member. Provided
The housing has an annular valve seat portion facing the central portion of the diaphragm in the liquid chamber and forming a valve portion together with the central portion. The liquid is supplied from the inflow side through the annular valve seat portion to the liquid chamber via the annular valve seat portion. An inflow path for inflowing the liquid and an outflow path for flowing the liquid in the liquid chamber to the outflow side are provided on the other opposite wall,
The diaphragm member is interlocked with the auxiliary shaft along with the axial movement of the drive shaft toward the other opposing wall. When the central portion of the diaphragm is seated on the annular valve seat portion, the valve portion is closed, and the diaphragm member is moved by the auxiliary shaft toward the one opposing wall of the drive shaft. The diaphragm valve opens when the central portion of the diaphragm moves away from the annular valve seat in conjunction with the axial movement of the diaphragm. The driving means,
The one side chamber and the other side chamber are slidably fitted along the axial direction between the one opposing wall and the partition in the hollow portion of the cylindrical peripheral wall, and the one side chamber and the other side wall and the partition A piston defining the hollow portion of the cylindrical peripheral wall so as to be formed on the side,
Biasing means for biasing the piston toward one of the other chamber and the one chamber,
The said drive shaft is a piston shaft integrally extended from the said piston through the said other side chamber, and is coaxially connected with the extension end part of the said auxiliary shaft of the said diaphragm member, The Claims characterized by the above-mentioned. 6. The diaphragm valve according to 5. The driving means,
A solenoid fitted along the axial direction between the one opposing wall and the partition wall in the hollow portion of the cylindrical peripheral wall,
A plunger that is axially inserted as the drive shaft into the solenoid and extends toward the partition wall;
Biasing means for biasing the plunger toward the partition or in the opposite direction,
The diaphragm valve according to claim 5, wherein the plunger is coaxially connected at an extended end thereof to an extended end of the auxiliary shaft of the diaphragm member.   The said diaphragm member is provided with the fluororesin reinforcement annular body which is laser-welded along the outer peripheral part in one side surface among the both surfaces of the said diaphragm, The any one of Claims 5-7 characterized by the above-mentioned. 2. The diaphragm valve according to 1.   The diaphragm valve according to any one of claims 5 to 8, wherein the diaphragm member is formed in a film shape by extruding or compressing PFA with the diaphragm.   In the diaphragm member, the auxiliary shaft has an outer diameter within a range of 1 (mm) or more and 4 (mm) or less, and the diaphragm has a diameter of 0.1 (mm) or more and 0.5 (mm). 10. The diaphragm valve according to claim 9, having a thickness within the following range:

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