Diaphragm valve for high temperature

Abstract

Provided is a high-temperature diaphragm valve capable of stably opening and closing the valve even in a high-temperature environment, and capable of preventing a decrease in sealing performance. A diaphragm valve (1) for high temperature is provided with: a holder (80) that moves to a valve opening / closing position in conjunction with a valve stem (30) in a state in which a seal member (81) suspended by a diaphragm (33) that hermetically closes a valve chamber (12c) is held, the seal member (81) being in contact with a valve contact surface (12a) when the valve is closed; and a pull-up and aligning mechanism (50) that connects the valve stem (30) and the holder (80). When the valve is opened, the holding seat (80) is forcibly pulled up by means of the pull-up and aligning mechanism (50), and when the valve is closed, the sealing member (81) held by the holding seat seals the valve contact surface (12a) with a uniform force by means of the pull-up and aligning mechanism (50).

Description

Technical Field

[0001] This invention relates to diaphragm valves for high-temperature applications, and more particularly to diaphragm valves for high-temperature applications in which a retaining seat is moved to the valve open / closed position by means of a valve stem, the retaining seat being suspended by means of a diaphragm that hermetically seals the valve chamber, and holding a sealing member that is abutted against the valve contact surface when the valve is closed. Background Technology

[0002] In the past, diaphragm valves were often used as on / off valves in gas supply piping systems for semiconductor manufacturing equipment, solar cell manufacturing equipment, liquid crystal manufacturing equipment, etc., which required less dead space and suppression of particulate matter generation.

[0003] In this type of diaphragm valve, the sealing component that seals the valve seat is not located on the valve body side, but on the valve body side that is linked to the up-and-down movement of the valve stem.

[0004] For example, Patent Document 1 describes a diaphragm valve with the following structure: a retainer seat that maintains a conical sealing component is combined with a diaphragm component inside the valve box; the retainer seat and the diaphragm component clamp the outer periphery of the inner diameter of the diaphragm; the diaphragm component is held freely up and down by the valve cover; and the retainer seat is suspended by the diaphragm component by clamping the outer periphery of the diaphragm with the valve cover.

[0005] Furthermore, Patent Document 2 describes a diaphragm valve with the following structure: a valve body having a fluid inlet passage, a fluid outlet passage, a valve chamber, and a valve seat; a valve cover nut screwed onto the valve body; a valve stem that is freely supported by being screwed onto the valve cover nut; a handle mounted on the upper end of the valve stem; a retaining seat that is freely supported by being mounted on the lower end of the valve stem; a flexural restraint body that passes through a support shaft protruding above the retaining seat and is located below the support shaft; and a metal diaphragm whose outer periphery is clamped and supported between the valve body and the valve cover nut, and whose inner periphery is welded to the retaining seat and the flexural restraint body; the retaining seat is suspended by means of the diaphragm.

[0006] Furthermore, examples of this type of conventional diaphragm valve include: Figure 8 The structure is shown. In this diaphragm valve 200, air is supplied to the interior of the bellows 210, and the lower surface of the bellows flange 220, which expands and descends through the bellows 210, contacts the roller 231 on one end side of the cam portion 230. As a result, one end side of the cam portion 230 tilts downward, and the valve stem 240 rises by means of the roller 232 on the other end side, which tilts upward.

[0007] If the valve stem 240 rises in this way, the elastic restoring force of the diaphragm 250 and the elastic force of the lifting spring 260 will be used to lift the diaphragm 270 and the retaining seat 280 connected to the diaphragm 270, and the diaphragm valve 200 will be in the open state where the sealing component 281 leaves the valve contact surface 290.

[0008] On the other hand, if the air supply is stopped and the bellows 210 is reduced, the support 242 in the diaphragm valve 200 is pushed down by the elastic force of the spring 241, and the valve stem 240, which is locked in the support 242, descends. The lower end of the valve stem 240 abuts against the upper end of the diaphragm 270, and the diaphragm 270 exerts a descending force.

[0009] Therefore, the force that resists the combined elastic force of the diaphragm 250 and the lifting spring 260 causes the diaphragm 270 to descend. As a result, the retaining seat 280 connected to the diaphragm 270 descends, and the diaphragm valve 200 is in a closed state where the sealing member 281 abuts against the valve contact surface 290.

[0010] However, the requirements for heat resistance have been increasing recently, requiring such diaphragm valves to withstand use in high-temperature environments exceeding 300 degrees Celsius.

[0011] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2020-159406 Patent document 2: Japanese Patent Application Publication No. 11-182708. Summary of the Invention

[0012] The technical problem that the invention aims to solve However, when using diaphragm valves in high-temperature environments exceeding 300 degrees Celsius, the elastic resilience of the diaphragm decreases due to the high temperature, as seen in conventional diaphragm valves. Figure 8 In the diaphragm valve shown, in addition to the diaphragm, the elastic force of the lifting spring also decreases. Therefore, the force that causes the retaining seat to rise when the valve is open is reduced. As a result, even if the valve stem rises and is moved to the open position, the valve is in a closed state with the sealing element abutting against the valve contact surface, and the opening and closing action of the valve may become unstable.

[0013] Furthermore, for conventional diaphragm valves, when using high-heat-resistant resin or metal materials that can withstand operating environments above 300 degrees Celsius to prevent melting due to high-temperature fluids as sealing components, the sealing performance is significantly affected if the self-aligning accuracy of the sealing component relative to the valve contact surface is low due to the reduced elasticity. Therefore, it is necessary to further improve the self-aligning accuracy of the retaining seat.

[0014] However, for conventional diaphragm valves with a structure in which the retainer is suspended by a diaphragm, if there is wobbling between the diaphragm and the valve cover or between the valve stem and the valve cover nut when the valve is closed, and the retainer is tilted, the sealing element held by the tilted retainer will be pressed against the valve contact surface in an tilted state, which may reduce the valve's sealing performance.

[0015] This invention was developed to solve previous technical problems, and its purpose is to provide a high-temperature diaphragm valve that can stably perform valve opening and closing operations even in high-temperature environments and prevent the decline in sealing performance.

[0016] Methods for solving technical problems To achieve the above objective, the invention of technical solution 1 is a diaphragm valve for high temperature applications, comprising: a retaining seat, which is suspended by means of a diaphragm that airtightly seals the valve chamber, and moves to the valve open / closed position by means of a valve stem while holding a sealing member that abuts against the valve contact surface when the valve is closed; and a pull-up-aligning mechanism that connects the valve stem to the retaining seat; when the valve is open, the retaining seat is forcibly pulled up by means of the pull-up-aligning mechanism, and when the valve is closed, the sealing member held by the retaining seat is sealed against the valve contact surface with uniform force by means of the pull-up-aligning mechanism.

[0017] The invention related to technical solution 2 is a diaphragm valve for high temperature applications. The pull-up self-aligning mechanism includes: a diaphragm member, an inner peripheral portion of the diaphragm whose outer peripheral portion is held by the valve body and a retaining seat; and a connecting member, configured to be fitted between a lower end recess of the valve stem and an upper end recess of the diaphragm member, thereby connecting the valve stem and the diaphragm member. By means of the downward movement of the valve stem for valve closing, the valve stem abuts against the two bottom surfaces of the lower end recess and the upper end recess, thereby transmitting the axial force of the valve stem to the diaphragm member.

[0018] The invention related to technical solution 3 is a diaphragm valve for high temperature, wherein the connecting component has arc-shaped curved surfaces formed on the upper and lower end faces; by means of the downward movement of the valve stem for valve closing, the arc-shaped curved surfaces of the upper and lower end faces are respectively abutted against the bottom surfaces of the lower and upper end recesses.

[0019] The invention related to technical solution 4 is a diaphragm valve for high temperature applications. The connecting component has a connecting through hole formed in a direction substantially orthogonal to the axial direction. It is connected to the diaphragm via a connecting pin inserted through the connecting through hole, and is connected to the valve stem via a locking step portion that locks against a locking step portion provided in the lower end recess. By means of the upward movement of the valve stem for valve opening, the locking step portion of the valve stem is abutted against the locking step portion of the connecting component, and the lower inner edge surface of the connecting through hole is abutted against the connecting pin.

[0020] The invention related to technical solution 5 is a diaphragm valve for high temperature, wherein a spacer is disposed on the bottom surface of the upper recess; by means of the downward movement of the valve stem for valve closing, the arc-shaped curved surface of the lower end face is abutted against the spacer.

[0021] The invention related to technical solution 6 is a diaphragm valve for high temperature applications, wherein the sealing component is made of polyimide resin.

[0022] The invention related to technical solution 7 is a diaphragm valve for high temperature applications, wherein the sealing member is annular; the retaining seat has an annular receiving portion for accommodating the sealing member; it includes: a sealing retaining member having a cylindrical portion that fits the inner surface of the cylinder with the inner circumferential surface of the annular receiving portion, holding the sealing member in a position concentric with the retaining seat; and an annular buffer member being held between the sealing retaining member and the bottom surface of the annular receiving portion, and having its inner circumferential surface fit with the inner circumferential surface of the annular receiving portion, and being held in the annular receiving portion in a position concentric with the retaining seat; the sealing member is held in the annular receiving portion in a state where it is radially outwardly expanded compared to the annular buffer member and a gap is formed between the surface facing the bottom surface of the annular receiving portion and the bottom surface.

[0023] The invention related to technical solution 8 is a diaphragm valve for high temperature, wherein the annular buffer component is made of a material with higher buffering capacity than the sealing component.

[0024] The invention related to technical solution 9 is a diaphragm valve for high temperature, wherein the sealing and retaining member has a protruding edge portion that protrudes radially outward at the end of the cylindrical portion; the sealing member is formed with a stepped abutting surface that abuts against the outer peripheral surface of the cylindrical portion including the protruding edge portion.

[0025] The invention related to technical solution 10 is a diaphragm valve for high temperature, wherein the sealing member has a recess on the bottom side of the annular receiving portion having a circumferential side slightly separated from the outer circumferential surface of the annular buffer member, and the annular buffer member is disposed thereon; a gap is formed between the surface of the annular sealing member and the bottom surface of the annular receiving portion, which is radially outward from the recess.

[0026] The invention related to technical solution 11 is a diaphragm valve for high temperature applications, wherein the sealing component is made of polyimide resin and the annular buffer component is made of perfluoroalkoxy resin.

[0027] Invention Effects According to the invention of relevant technical solution 1, there is a pull-up self-aligning mechanism that connects the valve stem and the retaining seat.

[0028] Therefore, even if the elastic recovery force of the diaphragm decreases due to use in high-temperature environments, and even if the retaining seat is prone to wobbling due to suspension by the diaphragm, the retaining seat is forcibly pulled up by the pull-up-alignment mechanism when the valve is open, and the sealing component held by the retaining seat is sealed with a uniform force on the valve contact surface by the pull-up-alignment mechanism when the valve is closed.

[0029] Therefore, it can stably open and close the valve even in high-temperature environments and prevent a decrease in sealing performance.

[0030] According to the invention of related technical solution 2, the pull-up-alignment mechanism includes: a diaphragm member, the inner peripheral portion of which is held by the valve body and the outer peripheral portion of the diaphragm member is clamped by a retaining seat; and a connecting member, which is configured to be fitted between the lower end recess of the valve stem and the upper end recess of the diaphragm member and to connect the valve stem and the diaphragm member. By means of the downward movement of the valve stem for valve closing, the valve stem abuts against the two bottom surfaces of the lower end recess and the upper end recess, and transmits the axial force of the valve stem to the diaphragm member.

[0031] Therefore, even if the elastic recovery force of the diaphragm decreases due to use in a high-temperature environment, the diaphragm connected to the valve stem via the connecting member moves upward in conjunction with the upward movement of the valve stem for valve opening, and can reliably move the retaining seat connected to the diaphragm to the valve open position where the sealing member leaves the valve contact surface.

[0032] Furthermore, when the valve is closed, even in the event of sloshing, the axial force of the valve stem caused by the downward movement of the valve stem is transmitted to the retaining seat via the connecting component through the bottom surface of the upper recess of the diaphragm. The retaining seat is aligned and then abuts against the valve contact surface after the sealing component has been aligned.

[0033] Therefore, it can stably open and close the valve even in high-temperature environments and prevent a decrease in sealing performance.

[0034] According to the invention of relevant technical solution 3, the connecting component has arc-shaped curved surfaces formed on the upper and lower end faces; by means of the downward movement of the valve stem for valve closing, the arc-shaped curved surfaces of the upper and lower end faces are respectively abutted against the bottom surfaces of the lower and upper end recesses.

[0035] Therefore, when the valve is closed, the upper end face of the connecting component reliably abuts against the bottom surface of the valve stem recess in the axial direction, and the lower end face of the connecting component reliably abuts against the bottom surface of the diaphragm recess in the axial direction. This allows the axial force caused by the downward movement of the valve stem to be transmitted to the bottom surface of the diaphragm recess without being affected by the tilt of the diaphragm. As a result, the retaining seat is self-aligned, allowing the sealing component to abut against the valve contact surface in the self-aligned state.

[0036] According to the invention of relevant technical solution 4, the connecting component has a connecting through hole in a direction substantially orthogonal to the axial direction, and is connected to the diaphragm via a connecting pin inserted through the connecting through hole, and is connected to the valve stem via a locking step portion that locks against a locking step portion provided in the lower end recess; by means of the upward movement of the valve stem for valve opening, the locking step portion of the valve stem is abutted against the locking step portion of the connecting component, and the lower inner edge surface of the connecting through hole is abutted against the connecting pin.

[0037] Thus, by means of the upward movement of the valve stem when the valve is opened, the connecting component causes the locking step to be locked in the locking step of the valve stem, and is pulled upward and moves upward. The diaphragm connected to the upward moving connecting component via the connecting pin moves upward, keeping the seat rising.

[0038] Therefore, when the valve is open, the retaining seat can be reliably raised to the valve open position.

[0039] According to the invention of relevant technical solution 5, a spacer is disposed on the bottom surface of the upper recess of the diaphragm member; by means of the downward movement of the valve stem for valve closing, the arc-shaped curved surface of the lower end face is abutted against the spacer.

[0040] Therefore, by adjusting the shape, material, hardness, surface condition, thickness, number of pieces, etc., the self-aligning condition of the retainer can be easily adjusted.

[0041] According to the invention of relevant technical solution 6, by making the sealing component into polyimide resin, damage to the sealing component caused by high temperature can be prevented even in use environments above 300 degrees Celsius, and the sealing performance can be maintained by means of the self-aligning function brought by the pull-up self-aligning mechanism.

[0042] According to the invention of relevant technical solution 7, the sealing component is annular; the retaining seat has an annular receiving portion for receiving the sealing component.

[0043] In addition, it includes: a sealing and retaining member having a cylindrical portion that fits the inner surface of the cylinder with the inner circumferential surface of the annular receiving portion, holding the sealing member in a position concentric with the retaining seat; and an annular buffer member being held by the sealing and retaining member and the bottom surface of the bottom side of the annular receiving portion of the sealing member, and having its inner circumferential surface fit with the inner circumferential surface of the annular receiving portion, and being held in the annular receiving portion in a position concentric with the retaining seat.

[0044] Furthermore, the sealing member is held within the annular receiving portion in a state where it expands radially outward compared to the annular buffer member, and a gap is formed between the surface facing the bottom of the annular receiving portion and the bottom surface.

[0045] Thus, by means of a simple structure in which an annular buffer member is fitted into the inner circumferential surface of the annular receiving portion and held in a position concentric with the retaining seat on the bottom side of the annular receiving portion, and a gap is provided between the sealing member in the region on the outer diameter side of the annular buffer member and the bottom surface of the annular receiving portion, when the sealing member abutting against the valve contact surface compresses the annular buffer member toward the bottom surface of the annular receiving portion, the buffering property of the annular buffer member is effectively utilized by utilizing the gap with the annular receiving portion, while being compressed toward the bottom surface together with the annular buffer member, and deformed for self-alignment by utilizing the gap.

[0046] Furthermore, since the annular buffer component is located on the bottom side of the annular housing, it does not come into contact with the control fluid by means of the sealing and retaining components and the sealing components, so it is possible to prevent the decrease in buffering performance caused by high temperature, and it is possible to use a material with higher buffering performance than the sealing component, although it has lower heat resistance.

[0047] Therefore, according to the invention of relevant technical solution 7, even in a wide range of temperature environments, it is possible to improve the self-aligning performance while maintaining airtightness with a simple structure.

[0048] According to the invention of relevant technical solution 8, by using an annular buffer member made of a material with higher buffering capacity than the sealing member, the buffering capacity of the annular buffer member can be used to improve the following of the sealing member to the valve contact surface, thereby improving the airtightness.

[0049] According to the invention of related technical solution 9, the sealing retaining member has a protruding edge portion that protrudes radially outward at the end of the cylindrical portion; the sealing member is formed with a stepped abutting surface that abuts against the outer peripheral surface of the cylindrical portion including the protruding edge portion; thereby, when the sealing member abuts against the valve seat and is compressed, even if the sealing member moves relative to the sealing retaining member in the axial direction, the control fluid will not seep through the stepped abutting portion between the sealing retaining member and the sealing member, so as to prevent the control fluid from seeping into the gap between the sealing member and the bottom surface of the annular receiving portion.

[0050] According to the invention of related technical solution 10, the sealing member has a recess on the bottom side of the annular receiving portion, which has a circumferential side slightly separated from the outer circumferential surface of the annular buffer member and is in which the annular buffer member is disposed; a gap is formed between the surface of the annular sealing member and the bottom surface of the annular receiving portion, which is radially outward from the recess; thereby, the minimum gap required for the annular buffer member to perform its buffering performance can be set, and as a result, the minimum gap required to improve airtightness can be set.

[0051] According to the invention of related technical solution 11, the sealing component is made of polyimide resin; the annular buffer component is made of perfluoroalkoxy resin. Thus, while using a sealing component made of polyimide resin with heat resistance of 300°C or higher in the part that comes into contact with the control fluid, an annular buffer component made of perfluoroalkoxy resin with higher buffering capacity than polyimide resin, although with heat resistance of less than 300°C, is used in the part that does not come into contact with the control fluid. Therefore, even in use in environments above 300°C, it is possible to improve self-aligning performance while maintaining airtightness with a simple structure. Attached Figure Description

[0052] Figure 1 This is a cross-sectional view showing the general structure of the diaphragm valve for high temperature in the first embodiment in the open state. Figure 2 yes Figure 1 An enlarged view of the periphery of the connecting components of the high-temperature diaphragm valve shown; Figure 3 This is a cross-sectional view showing the schematic structure of the diaphragm valve for high temperature in the closed state according to the first embodiment. Figure 4 yes Figure 3 An enlarged view of the periphery of the connecting components of the high-temperature diaphragm valve shown; Figure 5 This is a cross-sectional view showing the general structure of the diaphragm valve for high temperature in the second embodiment in the open state. Figure 6A yes Figure 5 An enlarged view of the periphery of the retaining seat of the high-temperature diaphragm valve shown; Figure 6B It is Figure 6A A further enlarged view of the area near the annular receiving portion of the holder shown; Figure 7 This diagram illustrates the operation of various components housed within the retaining seat during the valve closing action of a high-temperature diaphragm valve. Figure 8 It is a cross-sectional view showing the general structure of previous technologies. Detailed Implementation

[0053] The embodiments of the high-temperature diaphragm valve of the present invention are described in detail.

[0054] Furthermore, this disclosure is not limited to the embodiments shown below. It should also be noted that the drawings are schematic, and the dimensional relationships and ratios of the elements may differ from reality. Moreover, the drawings may contain portions with different dimensional relationships and ratios.

[0055] (First Embodiment) First, use Figures 1-4 The first embodiment will be described.

[0056] Figure 1 This is a cross-sectional view showing the schematic structure of the high-temperature diaphragm valve 1 in the valve open state according to the first embodiment. Figure 2 yes Figure 1 An enlarged view of the periphery of the connecting component 70 of the high-temperature diaphragm valve 1 shown. Figure 3 This is a cross-sectional view showing the schematic structure of the high-temperature diaphragm valve 1 in the valve closed state according to the first embodiment. Figure 4 yes Figure 3 An enlarged view of the periphery of the connecting component 70 of the high-temperature diaphragm valve 1 shown.

[0057] The high-temperature diaphragm valve 1 of the first embodiment is used in high-temperature environments, such as environments above 300 degrees Celsius.

[0058] Furthermore, this high-temperature diaphragm valve 1 can also be used in environments other than high temperatures. For example, it can be used not only in normal temperature environments but also in low temperature environments.

[0059] The high-temperature diaphragm valve 1 is a device that moves a retaining seat 80 to the valve stem 30 in a valve-opening or closed position. The retaining seat 80 is suspended by a diaphragm 33 that hermetically seals the valve chamber 12c and maintains a sealing member 81 that abuts against the valve contact surface 12a when the valve is closed. The high-temperature diaphragm valve 1 has a valve body 10 and an actuator 20 assembled on the upper part of the valve body 10.

[0060] <About Valve Body 10> The valve body 10 is made of metal and integrally consists of a valve body 11 that forms a gas flow path and a connecting part 13 connected to the actuator 20.

[0061] The valve body 11 has a valve seat 12 sandwiched in the middle, and is provided with a primary side flow path 11a that serves as the gas inflow side and a secondary side flow path 11b that serves as the gas outflow side. The valve seat 12 has a flat valve contact surface 12a that is in contact with / separated from the sealing member 81 described later.

[0062] The connecting portion 13 protrudes cylindrically from the valve body 11 above the valve seat 12 of the actuator 20. The connecting portion 13 has: an annular stepped portion 13a, on which the valve cover 32 sits with the outer peripheral edge 33b of the diaphragm 33 in a state of holding it; and a threaded portion 13b, which screws into the threaded portion 20b formed on the lower outer peripheral surface of the housing 20a of the actuator 20.

[0063] <About Actuator 20> Actuator 20 is a unit that moves valve stem 30 up and down to the valve open / closed position. The actuator 20 is provided with the following in the housing 20a: a lifting mechanism 40 for moving valve stem 30 up and down; and a pull-up-alignment mechanism 50, which has the function of pulling up the holding seat 80 in conjunction with the rising action of valve stem 30 when the valve is open, and the function of aligning the holding seat 80 when the valve is closed.

[0064] <Regarding the lifting mechanism 40 of actuator 20> The lifting mechanism 40 has a bellows 41 made of metal, multiple cams 42 and springs 44.

[0065] The bellows 41 is provided with a bellows flange 41a at its lower end, which receives the air introduced from the air inlet connector 21 into the interior.

[0066] Multiple cams 42 are pivotally mounted on the inner wall of housing 20a with rollers 42a and 42b at both ends.

[0067] Spring 44 applies a force via support 43 to move valve stem 30 downward to the valve closed position.

[0068] The roller 42a at one end of the cam 42 is flexibly disposed on the outer periphery of the bellows flange 41a, and the roller 42b at the other end is disposed in a groove formed in an annular shape on the upper outer periphery of the valve stem 30. Multiple such cams 42 are distributed around the outer periphery of the valve stem 30.

[0069] <Regarding the pulling up of actuator 20—alignment mechanism 50> The pull-up and self-aligning mechanism 50 has a diaphragm 60 and a connecting component 70.

[0070] Furthermore, the pull-up-alignment mechanism 50 includes a lower end recess 31 located at the lower end of the valve stem 30.

[0071] <Regarding the diaphragm 60 of the pull-up-alignment mechanism 50> The diaphragm 60 is connected to the retainer 80 and is held freely up and down by the valve cover 32. It also holds the inner peripheral edge 33a of the diaphragm 33 with the retainer 80. The outer peripheral edge 33b of the diaphragm 33 is held by the valve cover 32 and the valve body 10.

[0072] The diaphragm 60 is a bottomed cylindrical shape and has an upper end recess 61 with an upper end opening at the lower end of the connecting member 70 in a floating configuration.

[0073] In addition, in this embodiment, a wavy diaphragm 33 is used, but the shape of the diaphragm is not limited to this; for example, a dome-shaped diaphragm can also be used.

[0074] Furthermore, in this embodiment, a spacer 63 is disposed on the bottom surface 61a of the upper recess 61 of the diaphragm member 60, and the upper surface 63a of the spacer 63 forms the bottom surface 61a of the upper recess 61.

[0075] Therefore, for example, the state of the bottom surface of the upper recess 61 that abuts against the connecting component 70 can be appropriately adjusted by adjusting the shape, material, hardness, surface condition, thickness, and number of pieces of the spacer 63.

[0076] For example, the planar state of the bottom surface of the upper recess 61 can be adjusted to a state suitable for self-alignment by making the upper surface 63a of the spacer 63 flat or adjusting the surface roughness.

[0077] In addition, the material of the spacer 63 can be set to be different from that of the connecting part 70, so that the connecting part 70 is not easy to get stuck and can be adjusted to a state suitable for self-alignment.

[0078] Furthermore, by adjusting the thickness or number of spacers 63, the contact state between the connecting member 70 and the bottom surface 61a of the upper recess 61, with the spacers 63 sandwiched in the middle, can be adjusted to a state suitable for self-alignment.

[0079] On the other hand, at the lower end of the diaphragm member 60, a male threaded portion 62 is provided, which passes through a through hole 33c formed in the center of the diaphragm 33 and engages with the retainer 80. Furthermore, the inner peripheral edge portion 33a of the diaphragm 33 is clamped between the bottom surface of the diaphragm member 60 and the upper end surface of the retainer 80 around the base end of the male threaded portion 62.

[0080] At the lower end of the retaining seat 80 connected to the diaphragm 60, an annular sealing member 81 is held.

[0081] In this embodiment, the sealing component 81 is made of polyimide resin capable of withstanding high-temperature environments above 300 degrees Celsius.

[0082] In addition, other materials can be used for the sealing component 81 as long as it can withstand use in high-temperature environments above 300 degrees Celsius. For example, components made of metal materials can also be used.

[0083] Furthermore, the connection structure between the diaphragm member 60 and the retainer 80 is not limited to the screw-on connection structure described above. That is, any other connection structure is possible as long as the diaphragm 33, whose outer peripheral portion is held by the valve cover 32 and the valve body 10, can be connected to each other. For example, the diaphragm member 60 and the retainer 80 can be fixedly connected with the diaphragm 33 sandwiched in the middle.

[0084] <Regarding the connecting component 70 of the pull-up-alignment mechanism 50> The connecting member 70 has a generally cylindrical outer contour and a connecting through hole 72a formed in a direction generally orthogonal to the axial direction. The connecting member 70 is connected to the diaphragm member 60 via a connecting pin 73 inserted into the connecting through hole 72a, and is connected to the valve stem 30 via a locking step portion 71a, which is locked in a locking step portion 31b provided in the lower end recess 31 of the valve stem 30.

[0085] The connecting member 70 has an annular recess 70a formed on its outer peripheral surface, a head 71 formed on its upper part, and a cylindrical body 72 formed on its lower part below the annular recess 70a.

[0086] The lower surface of the head 71 becomes the locking surface 71b of the locking step portion 71a, and is disposed in the lower end recess 31 of the valve stem 30 in a floating state. The locking step portion 71a is locked in the locking step portion 31b provided in the lower end recess 31 of the valve stem 30.

[0087] The body portion 72 has the aforementioned connecting through hole 72a, and is disposed in the upper end recess 61 of the diaphragm member 60 in a movable state by means of a connecting pin 73. The connecting pin 73 passes through a through hole (not shown) formed in the upper end recess 61 of the diaphragm member 60 and is inserted into the connecting through hole 72a.

[0088] The connecting through hole 72a is an elongated hole with the length direction of the valve stem 30 as its length. More specifically, the length dimension of the connecting through hole 72a is set to be larger than the diameter of the connecting pin 73. Thus, a clearance is provided for the connecting member 70 to move downward, so that when the valve stem 30 descends to close the valve, the lower end face of the connecting member 70 abuts against the bottom surface of the upper end recess 61 of the diaphragm member 60, i.e., the upper surface 63a of the spacer member 63.

[0089] <Regarding the opening and closing action of diaphragm valve 1 for high temperature use> The following describes the opening and closing operation of the high-temperature diaphragm valve 1. First, the opening operation of the high-temperature diaphragm valve 1 will be explained.

[0090] High-temperature diaphragm valve 1 in the closed position (refer to...) Figure 3 When the valve changes to the open state, air is supplied into the bellows 41 through the air inlet connector 21. If air is supplied into the bellows 41, the bellows 41 expands, and the lower surface of the bellows flange 41a located at the lower part of the bellows 41 contacts the roller 42a on one end side of the cam 42.

[0091] Therefore, the cam 42 rotates in such a way that the other end tilts upward, lifting the valve stem 30 through the roller 42b on the other end, causing the valve stem 30 to rise.

[0092] If the valve stem 30 rises, the locking step 31b of the lower end recess 31 of the valve stem 30 abuts against the locking surface 71b of the connecting member 70, and the connecting member 70 is pulled up. If the connecting member 70 is pulled up, the lower inner edge surface of the connecting through hole 72a of the connecting member 70 abuts against the connecting pin 73, thereby lifting the diaphragm member 60, and thus the diaphragm member 60 rises.

[0093] If the diaphragm 60 rises, the retainer 80 connected to the diaphragm 60 rises, resulting in the valve open state where the sealing member 81 leaves the valve contact surface 12a.

[0094] At this time, the periphery of the inner peripheral edge 33a of the diaphragm 33, which is held by the diaphragm member 60 and the retainer 80, is pulled upward and elastically restored to a raised state.

[0095] Next, the valve closing action of the high-temperature diaphragm valve 1 will be explained.

[0096] When the high temperature is controlled, diaphragm valve 1 is in the valve open state as described above (refer to...). Figure 1 When the valve changes to the closed state, the supply of air through the air inlet connector 21 to the bellows 41 is stopped. If the supply of air to the bellows 41 is stopped, the support 43 is pushed down by the elastic force of the spring 44, and the valve stem 30 is stopped from descending by the support 43.

[0097] If the valve stem 30 descends, the bottom surface 31a of the lower end recess 31 of the valve stem 30 abuts against the arc-shaped curved surface 71c of the upper end face of the connecting member 70, and the connecting member 70 is pushed down. If the connecting member 70 is pushed down, the arc-shaped curved surface 72c of the lower end face of the connecting member 70 abuts against the upper surface 63a of the spacer 63, and the diaphragm 60 is pushed down.

[0098] Thus, as the diaphragm 60 is pushed down, the retaining seat 80 connected to the diaphragm 60 descends, resulting in the valve being closed when the sealing component 81 abuts against the valve contact surface 12a.

[0099] When the seat 80 is lowered, the connecting component 70 abuts against the two bottom surfaces 31a and 61a of the lower end recess 31 of the valve stem 30 and the upper end recess 61 of the diaphragm 60 through the downward movement of the valve stem 30, thereby transmitting the axial force of the valve stem 30 to the diaphragm 60.

[0100] This is because the connecting member 70 is positioned in a fitted state in the lower end recess 31 of the valve stem 30 and the upper end recess 61 of the diaphragm member 60. Regardless of the orientation of the diaphragm member 60, the bottom surface 31a of the lower end recess 31 of the valve stem 30 abuts against the upper end surface 71c of the connecting member 70, which is an arc-shaped curved surface. Furthermore, the bottom surface 61a of the upper end recess 61 of the diaphragm member 60, and more specifically, the upper surface 63a of the spacer member 63, abuts against the lower end surface 72c of the connecting member 70, which is an arc-shaped curved surface.

[0101] Therefore, even if the diaphragm 60 tilts relative to the axis of the valve stem 30 due to the wobbling between it and the valve cover 32, and the retainer 80 connected to the diaphragm 60 tilts, the diaphragm 60 is aligned, the retainer 80 is aligned, and the sealing member 81 is aligned and abuts against the valve contact surface 12a.

[0102] <Effects of the first implementation method> As described above, the high-temperature diaphragm valve 1 according to the relevant embodiment has a pull-up-alignment mechanism 50 that connects the valve stem 30 to the retaining seat 80.

[0103] Therefore, even if the elastic recovery force of the diaphragm 33 decreases due to use in high-temperature environments, and even if the retaining seat 80, which is prone to wobbling due to suspension by the diaphragm 33, is forcibly pulled up by the pull-up-alignment mechanism 50 when the valve is open. Moreover, when the valve is closed, the sealing member 81, held by the retaining seat 80, seals against the valve contact surface 12a with a uniform force.

[0104] Therefore, it can stably open and close the valve even in high-temperature environments and prevent a decrease in sealing performance.

[0105] Furthermore, in the high-temperature diaphragm valve 1 according to the relevant embodiment, the retaining seat 80 is aligned by means of the pull-up-aligning mechanism 50, so that the sealing member 81 abuts against the valve contact surface 12a in the aligned state and is sealed. Therefore, the high-temperature diaphragm valve 1 according to the relevant embodiment can improve the sealing performance.

[0106] Furthermore, the high-temperature diaphragm valve 1 of the relevant embodiment can reduce the thrust of the actuator used for valve closure, and by reducing the spring that will become the source of the thrust, the actuator can be made more compact, thus enabling the device to be more compact.

[0107] Furthermore, according to the high-temperature diaphragm valve 1 of the relevant embodiments, the pull-up-alignment mechanism 50 includes: a diaphragm member 60, which holds the inner peripheral edge of the diaphragm 33 with a retaining seat 80, the outer peripheral edge 33b of the diaphragm 33 being held by a valve cover 32 and a valve body 10; and a connecting member 70, which is configured to be fitted between the lower end recess 31 of the valve stem 30 and the upper end recess 61 of the diaphragm member 60 and to connect the valve stem 30 to the diaphragm member 60. By the downward movement of the valve stem 30 for valve closing, it abuts against the two bottom surfaces 31a, 61a of the lower end recess 31 and the upper end recess 61, and transmits the axial force of the valve stem 30 to the diaphragm member 60.

[0108] Therefore, even if the elastic recovery force of the diaphragm 33 decreases due to use in a high-temperature environment, it is still linked to the upward movement of the valve stem 30 for valve opening, and the diaphragm member 60 connected to the valve stem 30 moves upward via the connecting member 70. Moreover, the retaining seat 80 connected to the diaphragm member 60 can be reliably moved to the valve open position where the sealing member 81 leaves the valve contact surface 12a.

[0109] Furthermore, even if there is some movement between the diaphragm 60 and the valve cover 32 when the valve is closed, the axial force of the valve stem 30 caused by the downward movement of the valve stem 30 via the connecting member 70 is transmitted to the retaining seat 80 through the bottom surface 61a of the upper end recess 61 of the diaphragm 60, and the retaining seat 80 is aligned. Moreover, by aligning the retaining seat 80, the sealing member 81 is abutted against the valve contact surface 12a in the aligned state.

[0110] Therefore, it can stably open and close the valve even in high-temperature environments and prevent a decrease in sealing performance.

[0111] Furthermore, in the high-temperature diaphragm valve 1 according to the relevant embodiment, the connecting member 70 has arc-shaped curved surfaces formed on the upper end face 71c and the lower end face 72c. By the downward movement of the valve stem 30 for valve closing, the arc-shaped curved surfaces of the upper end face 71c and the lower end face 72c are respectively abutted against the two bottom surfaces 31a and 61a of the lower end recess 31 of the valve stem 30 and the upper end recess 61 of the diaphragm member 60.

[0112] Thus, when the valve is closed, the upper end face 71c of the connecting member 70 reliably abuts axially against the bottom surface 31a of the lower end recess 31 of the valve stem 30, and the lower end face 72c of the connecting member 70 reliably abuts axially against the bottom surface of the upper end recess 61 of the diaphragm member 60, more specifically against the upper surface 63a of the spacer member 63.

[0113] Therefore, the axial force caused by the downward movement of the valve stem 30 can be transmitted to the bottom surface 61a of the upper recess 61 of the diaphragm 60 without being affected by the tilt of the diaphragm 60. As a result, the retaining seat 80 is aligned, and the sealing member 81 can abut against the valve contact surface 12a in the aligned state.

[0114] Furthermore, according to the high-temperature diaphragm valve 1 of the relevant embodiment, the connecting member 70 has a connecting through hole 72a formed in a direction substantially orthogonal to the axial direction. It is connected to the diaphragm member 60 via a connecting pin 73 inserted through the connecting through hole 72a, and connected to the valve stem 30 via a locked step portion 71a. The locked step portion 71a is locked in a locked step portion 31b provided in the lower end recess 31 of the valve stem 30. By the upward movement of the valve stem 30 for valve opening, the locked step portion 31b of the valve stem 30 is abutted against the locked surface 71b of the locked step portion 71a of the connecting member 70, and the lower inner edge surface of the connecting through hole 72a is abutted against the connecting pin 73.

[0115] As a result, the valve stem 30 moves upward when the valve is opened, and the connecting member 70 is pulled upward and moves upward, causing the locking step 71a to lock onto the locking step 31b of the valve stem 30. Furthermore, the diaphragm 60, connected to the upwardly moving valve stem 30 via the connecting pin 73, moves upward, and the retaining seat 80 rises.

[0116] Therefore, when the valve is open, the retaining seat 80 can be reliably raised to the valve open position.

[0117] Furthermore, in the high-temperature diaphragm valve 1 according to the relevant embodiment, a spacer 63 is disposed on the bottom surface 61a of the upper end recess 61 of the diaphragm member 60. By the downward movement of the valve stem 30 for valve closing, the arc-shaped curved surface of the lower end surface 72c of the connecting member 70 is abutted against the upper surface 63a of the spacer 63.

[0118] Therefore, by adjusting the shape, material, hardness, surface condition, thickness, number of pieces, etc. of the spacer 63, the self-aligning condition of the retainer 80 can be easily adjusted.

[0119] Furthermore, according to the relevant embodiments, the high-temperature diaphragm valve 1 is made of polyimide resin for the sealing component 81, which can prevent damage caused by the high temperature of the sealing component 81 even in an operating environment of 300 degrees or higher, and can maintain the sealing performance through the self-aligning function provided by the pull-up self-aligning mechanism 50.

[0120] (Second Implementation) Next, use Figures 5-7 The second embodiment will be described.

[0121] Figure 5 This is a cross-sectional view showing the schematic structure of the high-temperature diaphragm valve 2 in the valve open state according to the second embodiment. Figure 6A yes Figure 5 An enlarged view of the periphery of the retaining seat 180 of the high-temperature diaphragm valve 2 shown. Figure 6B It is Figure 6AA further enlarged view of the area near the annular receiving portion 180a of the holder 180 shown. Figure 7 This diagram illustrates the operation of the components housed within the retaining seat 180 during the valve closing action of the high-temperature diaphragm valve 2.

[0122] Furthermore, in the second embodiment, the same reference numerals are used for the same parts as in the first embodiment, and repeated descriptions are omitted.

[0123] The high-temperature diaphragm valve 2 of the second embodiment differs from the high-temperature diaphragm valve 1 of the first embodiment in that the structure of the retaining seat 180 and the components retained inside the retaining seat 180 are different.

[0124] In the high-temperature diaphragm valve 2 of this embodiment, the retaining seat 180 holds the annular sealing member 181 and the annular buffer member 182 within the annular receiving portion 180a using the sealing retaining member 183.

[0125] <Regarding maintaining a seat angle of 180> The retainer 180 is made of a metal material such as stainless steel, and has an annular receiving portion 180a that retains the sealing member 181.

[0126] The annular receiving portion 180a has an opening 180b on the valve contact surface 12a side, and a cylindrical portion 180e is provided in the center, forming the inner peripheral surface 180c of the annular receiving portion 180a.

[0127] The cylindrical portion 180e is fitted with the inner circumferential surface 180c of the outer circumferential surface, i.e. the inner circumferential surface 180c of the annular receiving portion 180a, the inner cylindrical surface 183d of the sealing and retaining member 183, and the inner circumferential surface 182a of the annular buffer member 182, and functions as a part that holds the sealing and retaining member 183 and the annular buffer member 182 within the annular receiving portion 180a in a position concentric with the retaining seat 180.

[0128] <Regarding sealing components 181> In this embodiment, the sealing member 181 is made of a highly heat-resistant polyimide resin and is held in the annular receiving portion 180a with a gap 180g formed between the surface of the annular buffer member 182 that expands radially outward and faces the bottom surface 180d of the annular receiving portion 180a and the bottom surface 180d.

[0129] As described above, the sealing member 181 is held within the annular receiving portion 180a in a state where it is positioned concentrically with the retaining seat 180 by the sealing retaining member 183.

[0130] Sealing component 181, such as Figure 6BAs shown, a peripheral side surface 181aa, which is slightly separated from the outer peripheral side 182b of the annular receiving portion 182, and a recess 181a for arranging the annular buffer member 182 are formed on the surface of the bottom surface 180d of the annular receiving portion 180a.

[0131] A gap 180g is formed between the surface of the sealing member 181, which is radially outer of the recess 181a of the sealing member 181, and the bottom surface 180d of the annular receiving portion 180a.

[0132] In order to keep seat 180 in the valve closed position, the width of gap 180g is adjusted to the extent that the annular buffer member 182 can effectively exert its cushioning effect when the sealing member 181 is compressed against the valve contact surface 12a, and to the extent that the sealing member 181 can deform for self-alignment.

[0133] Furthermore, an annular protrusion 181c is provided on the bottom surface 181b of the recess 181a, which is pressed against the surface of the annular buffer member 182.

[0134] The annular protrusion 181c is located radially inward of the region where the gap 180g is formed, increasing the tightness of the seal 181 and the annular buffer 182 to cut off the infiltration path of the control fluid into the gap 180g.

[0135] In addition, sealing component 181, such as Figure 6B As shown, a stepped abutment surface 181d is formed that abuts against the outer peripheral surface 183c of the cylindrical portion 183a of the sealing and retaining member 183, including the protruding edge portion 183b described later.

[0136] The stepped abutment surface 181d has a first abutment surface 181e that abuts against the outer peripheral surface 183c of the protrusion 183b, a second abutment surface 181f that abuts against the surface of the protrusion 183b facing the bottom surface 180d of the annular receiving portion 180a, and a third abutment surface 181g that abuts against the outer peripheral surface of the end of the annular receiving portion 180a on the side of the bottom surface 180d of the sealing and retaining member 183.

[0137] In addition, the first abutting surface 181e and the third abutting surface 181g are the inner peripheral surfaces of the sealing member 181 that abut against the outer peripheral surface 183c of the sealing member 183 when the sealing member 181 is disposed in a position concentric with the retaining seat 180.

[0138] When the retaining seat 180 is in the valve open position, that is, when the sealing member 181 is in an elastically neutral state without being compressed, the three abutment surfaces 181e, 181f, and 181g of the sealing member 181 are in contact with the corresponding surfaces of the sealing retaining member 183.

[0139] Furthermore, the outer peripheral surface 181h of the sealing member 181 is inclined such that its outer diameter expands from the valve contact surface 12a side toward the bottom surface 181d side of the annular receiving portion 180a.

[0140] Thus, while minimizing the contact area with the annular receiving portion 180a, the sealing member 181 makes its outer peripheral surface 181h closely contact the outer peripheral surface 180f of the annular receiving portion 180a near the bottom surface 180d of the annular receiving portion 180a.

[0141] Therefore, it reliably prevents the control fluid from seeping into the gap 180g through the outer peripheral surface 181h of the sealing member 181 and the outer peripheral surface 180f of the annular receiving portion 180a.

[0142] <Regarding the sealing and retaining components 183> The sealing and retaining member 183 is made of a metal material such as stainless steel, and has a cylindrical part 183a on the inner circumferential surface 180c of the annular receiving part 180a that fits into the inner surface 183d of the cylinder, thus holding the sealing member 181 in a position concentric with the retaining seat 180.

[0143] The sealing retaining member 183 has a protruding edge 183b at the end of the cylindrical portion 183a, which protrudes radially outward and abuts against the stepped contact surface 181d of the sealing member 181.

[0144] The sealing member 181 is held in the annular receiving portion 180a in a concentric position with the retaining seat 180 by fitting the inner peripheral surfaces 181e and 181g into the outer peripheral surface 183c of the cylindrical portion 183a.

[0145] Furthermore, the sealing retaining member 183 is adjusted to a position lower than the valve seat abutment surface 181i of the sealing member 181 on the same side via the valve contact surface 12a, so that it does not abut against the valve contact surface 12a.

[0146] <Regarding the ring-shaped buffer component 182> The annular buffer member 182 is a ring-shaped sheet member with cushioning properties, and in this embodiment, it is made of a perfluoroalkoxy resin. That is, in this embodiment, a material with higher cushioning properties than the sealing member 181 is used as the annular buffer member 182.

[0147] Furthermore, in this embodiment, cushioning is a property of conforming to the shape of other objects it comes into contact with in a soft manner and of elasticity that recovers from a state of compression deformation.

[0148] In addition, high cushioning refers to the elasticity that recovers from compression deformation and high follow-through.

[0149] The annular buffer member 182 is held by the bottom surface 180d of the annular receiving portion 180a of the sealing and retaining member 183 and the sealing member 181, and the inner circumferential surface 182a is fitted into the inner circumferential surface 180c of the annular receiving portion 180a, and is held in the annular receiving portion 180a at a position concentric with the retaining seat 180.

[0150] Alternatively, the annular buffer member 182 can be any member with the same level of buffering as the sealing member 181, as long as it has buffering properties. This is because, since the annular buffer member 182 is positioned in a location that does not come into direct contact with the high-temperature control fluid, it can prevent a decrease in buffering properties even in a wide range of temperature environments, including high-temperature environments.

[0151] <Regarding the operation of the components housed within the retaining seat 180 during the opening and closing of the high-temperature diaphragm valve 2> In the valve opening operation of the high-temperature diaphragm valve 2 described above, if the holding seat 180 rises and the sealing member 181 leaves the valve contact surface 12a, the sealing member 181, which is compressed by contact with the valve contact surface 12a, and the annular buffer member 182, which is compressed by the sealing member 181, elastically recover.

[0152] On the other hand, during the valve closing operation of the high-temperature diaphragm valve 2, if the diaphragm 60 tilts relative to the axis of the valve stem 30 due to the wobbling between the valve cover 32, and the retaining seat 180 connected to the diaphragm 60 tilts, the pull-up-aligning mechanism 50 will also align the diaphragm 60. In the state where the retaining seat 180 is aligned, the sealing member 181 is abutted against the valve contact surface 12a.

[0153] After the sealing component 181 abuts against the valve contact surface 12a, if the retaining seat 180 moves further down in conjunction with the valve stem 30, then as Figure 7 As shown, the sealing member 181 is compressed by the reaction force received from the valve contact surface 12a, and the annular buffer member 182, which overlaps with the sealing member 181, is compressed on the bottom surface 180d side of the annular receiving portion 180a.

[0154] If the annular buffer member 182 is pushed by the sealing member 181, it will elastically compress and deform while softly following the sealing member 181. Therefore, the annular buffer member 182 is compressed and deformed in a state where no gap is generated between it and the sealing member 181 and it is pressed against the bottom surface 180d of the annular receiving portion 180a.

[0155] Therefore, the sealing member 181, which contacts the valve contact surface 12a, has improved cushioning performance by adding the cushioning property of the annular cushioning member 182 in addition to the cushioning property of the sealing member 181 itself, so as to deform in accordance with the valve contact surface 12a. In addition, by providing the above-mentioned gap 180g, the cushioning property of the annular cushioning member 182 can be effectively utilized during the period before the sealing member 181 is compressed while abutting against the bottom surface 180d of the annular receiving portion 180a.

[0156] In addition, the sealing member 181 deforms by utilizing its gap 180g to self-align the retainer 180.

[0157] That is, in this embodiment, the self-aligning function brought by the pull-up self-aligning mechanism 50 and the self-aligning function of the retainer 180 side are superimposed, which further improves the self-aligning performance.

[0158] Furthermore, when the sealing member 181 and the annular buffer member 182 are compressed due to the reaction force received by the sealing member 181 from the valve contact surface 12a, such as Figure 7 As shown, a gap 180h is generated between the sealing member 181 and the sealing retaining member 183.

[0159] Although this creates a gap 180h, by forming a stepped abutment surface 181d of the sealing member 181 outside the gap 180h that protrudes toward the corresponding surface of the sealing member 183, it further closes to the corresponding surface of the sealing member 183, thus preventing control fluid from seeping into the gap 180h.

[0160] <Effects of the second implementation method> According to the high-temperature diaphragm valve 2 of this embodiment, the retaining seat 180 has an annular receiving portion 180a that houses the sealing member 181. Furthermore, the high-temperature diaphragm valve 2 includes: a sealing retaining member 183 having a cylindrical portion 183a that engages with the inner circumferential surface 180c of the annular receiving portion 180a, holding the sealing member 181 in a position concentric with the retaining seat 180; and an annular buffer member 182, held between the sealing retaining member 183 and the bottom surface 180d of the annular receiving portion 180a, with its inner circumferential surface 182a engaging with the inner circumferential surface 180c of the annular receiving portion 180a, and held within the annular receiving portion 180a in a position concentric with the retaining seat 180. Furthermore, the sealing member 181 is radially outwardly expanded than the annular buffer member 182, and is held within the annular receiving portion 180a with a gap 180g formed between the surface facing the bottom surface 180d of the annular receiving portion 180a and the bottom surface 180d.

[0161] Thus, a simple structure is formed in which a gap 180g is provided between the sealing member 181 in the region of the outer diameter side of the annular buffer member 182 and the bottom surface 180d of the annular receiving portion 180a, wherein the annular buffer member 182 is fitted with the inner circumferential surface 180c of the annular receiving portion 180a and is held in a concentric position with the retaining seat 180 on the bottom surface 180d side of the annular receiving portion 180a.

[0162] Moreover, with this simple structure, when the sealing member 181 abutting against the valve contact surface 12a compresses the annular buffer member 182 toward the bottom surface 180d of the annular receiving portion 180a, the annular buffer member 182 effectively utilizes the buffering property of the annular buffer member 182 by utilizing the gap 180g between the annular receiving portions 180a, and is compressed toward the bottom surface 180d together with the annular buffer member 182, and deforms for self-alignment by utilizing the gap 180g.

[0163] Furthermore, since the annular buffer member 182 is located on the bottom surface 180d side of the annular receiving portion 180a, it does not come into contact with the control fluid by means of the sealing retaining member 183 and the sealing member 181. Therefore, it can prevent the decrease in buffering performance caused by high temperature, and it can use a material with lower heat resistance but higher buffering performance compared to the sealing member 181.

[0164] Therefore, the high-temperature diaphragm valve 2 according to this embodiment can improve self-aligning performance while maintaining airtightness in a wide range of temperature environments, including high-temperature environments, with a simple structure.

[0165] Furthermore, according to the high-temperature diaphragm valve 2 of this embodiment, since the retaining seat 180 side is also equipped with a self-aligning function by means of the pull-up self-aligning mechanism 50, the self-aligning performance can be improved, especially for valves with large sizes that are difficult to self-align.

[0166] Furthermore, according to the high-temperature diaphragm valve 2 of the relevant embodiment, the annular buffer member 182 is made of a material with higher buffering capacity than the sealing member 181. The buffering capacity of the annular buffer member 182 is used to improve the following of the sealing member 181 to the valve contact surface 12a, thereby improving the airtightness.

[0167] Furthermore, according to the high-temperature diaphragm valve 2 of the relevant embodiment, the sealing retaining member 183 has a protruding edge 183b at the end of the cylindrical portion 183a, which protrudes radially outward in a protruding edge shape; the sealing member 181 is formed with a stepped abutting surface 181d that abuts against the outer peripheral surface 183c of the cylindrical portion 183a, which includes the protruding edge 183b, in a stepped manner; thereby, when the sealing member 181 abuts against the valve seat 12 and is compressed, even if the sealing member 181 moves relative to the sealing retaining member 183 in the axial direction, the control fluid will not seep through the stepped abutting portion between the sealing retaining member 183 and the sealing member 181, so it is possible to prevent the control fluid from seeping into the gap 180g between the sealing member 181 and the bottom surface 180d of the annular receiving portion 180a.

[0168] Furthermore, according to the high-temperature diaphragm valve 2 of the relevant embodiment, the sealing member 181 has a peripheral side surface 181aa that is slightly separated from the outer peripheral surface 182b of the annular receiving portion 182, and a recess 181a for arranging the annular buffer member 182, formed on the side of the bottom surface 180d of the annular receiving portion 180a; a gap 180g is formed between the surface of the sealing member 181 that is radially outward from the recess 181a and the bottom surface 180d of the annular receiving portion 180a; thereby, the minimum gap 180g required to enable the annular buffer member 182 to perform its buffering performance can be set, and as a result, the minimum gap 180g required to improve airtightness can be set.

[0169] Furthermore, according to the high-temperature diaphragm valve 2 of the relevant embodiments, the sealing member 181 is made of polyimide, and the annular buffer member 182 is made of perfluoroalkoxy resin. The sealing member 181, which is made of polyimide resin with heat resistance of 300°C or higher, is used in the part that comes into contact with the control fluid, while the annular buffer member 182, which is made of perfluoroalkoxy resin with higher buffering capacity than polyimide resin but less than 300°C, is used in the part that does not come into contact with the control fluid. Therefore, even in use in environments above 300°C, the self-aligning performance can be improved while maintaining airtightness with a simple structure.

[0170] The embodiments of this disclosure have been described above, but this disclosure is not limited to the above embodiments. Various changes can be made as long as they do not depart from its spirit.

[0171] For example, in the above embodiment, a structure is illustrated in which the connecting member 70 is connected to the diaphragm member 60 via a connecting pin 73, but the connecting member and the diaphragm member may also be connected without using a connecting pin. For example, an annular protrusion may be provided on the outer peripheral surface of the cylindrical body portion of the connecting member, and this annular protrusion may be positioned within an annular recess provided on the inner peripheral surface of the upper recess of the diaphragm member. Furthermore, the annular recess may be configured to have a clearance width that allows the connecting member to move downwards when the valve stem descends to close the valve, so that the lower end surface of the connecting member abuts against the bottom surface of the recess of the diaphragm member, i.e., the upper surface of the spacer.

[0172] Furthermore, for example, in the above embodiment, a structure is illustrated in which the outer peripheral portion 33b of the diaphragm 33 is held between the valve cover 32 and the valve body 10, but it is sufficient to simply hold the outer peripheral portion 33b of the diaphragm 33 in the valve body 10.

[0173] Furthermore, for example, in the above-described embodiment, a spacer 63 is provided on the bottom surface 61a of the upper recess 61 of the diaphragm member 60, and the upper surface 63a of the spacer 63 abuts against the lower end surface 72c of the connecting member 70. However, it is also possible to omit the spacer 63 from the diaphragm member 60, so that the bottom surface 61a of the upper recess 61 abuts against the lower end surface 72c of the connecting member 70.

[0174] Furthermore, for example, in the above embodiments, a structure is illustrated in which the sealing member 181 is made of polyimide resin and the annular buffer member 182 is made of perfluoroalkoxy resin. However, the sealing member 181 and the annular buffer member 182 are not limited to these resins. For example, other materials can be used as long as the sealing member 181 is a sealing member and the annular buffer member 182 is a buffering member.

[0175] The embodiments disclosed herein are illustrative in all respects and should not be considered restrictive. The above embodiments may be omitted, substituted, or modified in various forms without departing from the claims and their spirit.

[0176] Explanation of reference numerals in the attached figures 1, 2 High-temperature diaphragm valves 10 Valve body 12a Valve contact surface 30 Valve stem 31 Lower end concave part 31a Bottom surface 31b Stop step section 33 Diaphragm 33a Inner peripheral region 33b Peripheral edge 50 Pull-up - Centering Mechanism 60 Diaphragm components 61 Upper concave part 61a Bottom 63 Spacer 70 Connecting components 71a is stuck on the step. 71c Circular curved surface (top surface) 72a Connecting Through Hole 72c Circular curved surface (lower end face) 73 Connecting pin 80, 180 Keep seat 81, 181 Sealing components 180a Circular containment section 180b opening 180c inner circumference 180d bottom 180e Cylindrical section 180f outer perimeter 180g gap 180h interval 181a recess 181aa Side view 181b bottom surface 181c annular protrusion 181d Stepped abutment surface 181e First contact surface 181f Second contact surface 181g Third contact surface 181h outer periphery 181i Valve seat contact surface 182 Ring-shaped buffer component 182a Inner circumferential surface 182b outer perimeter 183 Sealing Retention Components 183a cylindrical part 183b Protruding edge 183c outer perimeter 183d Inner surface of cylinder

Claims

1. A diaphragm valve for high-temperature applications, characterized in that, have: The retainer seat, suspended by a diaphragm that hermetically seals the valve chamber, moves in conjunction with the valve stem to the valve open / closed position while maintaining a sealing element that abuts against the valve contact surface when the valve is closed; and Pull up the self-aligning mechanism to connect the aforementioned valve stem to the aforementioned retaining seat; When the valve is open, the aforementioned retaining seat is forcibly pulled up by the aforementioned pull-up-alignment mechanism. When the valve is closed, the sealing component held by the aforementioned retaining seat is sealed with the aforementioned valve contact surface by a uniform force by the aforementioned pull-up-alignment mechanism.

2. The high-temperature diaphragm valve as described in claim 1, characterized in that, The aforementioned pull-up and center-aligning mechanism has the following features: The diaphragm member, with its inner peripheral edge held by the valve body, has its outer peripheral edge clamped by the aforementioned retainer; and The connecting component is configured to be fitted between the lower end recess of the valve stem and the upper end recess of the diaphragm member, thereby connecting the valve stem and the diaphragm member. By means of the downward movement of the valve stem for valve closing, it abuts against the two bottom surfaces of the lower end recess and the upper end recess, thereby transmitting the axial force of the valve stem to the diaphragm member.

3. The high-temperature diaphragm valve as described in claim 2, characterized in that, The aforementioned connecting component has arc-shaped curved surfaces on its upper and lower end faces; By means of the downward movement of the aforementioned valve stem used for valve closure, the arc-shaped curved surfaces of the aforementioned upper end face and the aforementioned lower end face are respectively abutted against the bottom surfaces of the aforementioned lower end recess and the aforementioned upper end recess.

4. The high-temperature diaphragm valve as described in claim 2 or 3, characterized in that, The aforementioned connecting component has a connecting through hole in a direction substantially orthogonal to the axial direction, and is connected to the aforementioned diaphragm via a connecting pin inserted through the connecting through hole, and is connected to the aforementioned valve stem via a locking step portion that locks against the locking step portion provided in the aforementioned lower end recess. By means of the upward movement of the aforementioned valve stem for opening the valve, the locking step portion of the aforementioned valve stem is abutted against the locking step portion of the aforementioned connecting member, and the lower inner edge surface of the aforementioned connecting through hole is abutted against the aforementioned connecting pin.

5. The high-temperature diaphragm valve as described in claim 2 or 3, characterized in that, A spacer is provided on the bottom surface of the aforementioned upper recess; By means of the downward movement of the aforementioned valve stem used for valve closure, the arc-shaped curved surface of the aforementioned lower end face is abutted against the aforementioned spacer.

6. The high-temperature diaphragm valve as described in claim 1, characterized in that, The aforementioned sealing component is made of polyimide resin.

7. The high-temperature diaphragm valve as described in claim 1 or 2, characterized in that, The aforementioned sealing component is annular; The aforementioned retainer has an annular receiving portion for accommodating the aforementioned sealing component; have: The sealing and retaining member has a cylindrical portion that fits the inner surface of the cylinder with the inner circumferential surface of the aforementioned annular receiving portion, holding the sealing member in a position concentric with the aforementioned retaining seat; and The annular buffer member is held between the bottom surface of the aforementioned sealing and retaining member and the bottom surface of the aforementioned annular receiving portion of the aforementioned sealing member, and the inner circumferential surface is fitted with the inner circumferential surface of the annular receiving portion, and is held in the aforementioned annular receiving portion at a position concentric with the aforementioned retaining seat. The aforementioned sealing member is held within the aforementioned annular receiving portion in a state where it is expanded radially outward from the aforementioned annular buffer member and a gap is formed between the surface facing the bottom of the aforementioned annular receiving portion and the aforementioned bottom surface.

8. The high-temperature diaphragm valve as described in claim 7, characterized in that, The aforementioned annular buffer component is made of a material with higher cushioning properties than the aforementioned sealing component.

9. The high-temperature diaphragm valve as described in claim 7, characterized in that, The aforementioned sealing and retaining member has a protruding edge portion that protrudes radially outward at the end of the aforementioned cylindrical portion; The aforementioned sealing member has a stepped contact surface that abuts against the outer peripheral surface of the aforementioned cylindrical portion, which includes the aforementioned protruding edge.

10. The high-temperature diaphragm valve as described in claim 7, characterized in that, The aforementioned sealing member has a circumferential side surface that is slightly separated from the outer circumferential surface of the aforementioned annular receiving portion and a recess for arranging the aforementioned annular buffer member on the bottom side surface of the aforementioned annular receiving portion. The aforementioned gap is formed between the surface of the aforementioned annular sealing member, which is radially outer of the aforementioned recess, and the bottom surface of the aforementioned annular receiving portion.

11. The high-temperature diaphragm valve as described in claim 7, characterized in that, The aforementioned sealing component is made of polyimide resin; The aforementioned annular buffer component is made of perfluoroalkoxy resin.

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