JP6033912B2 - Diaphragm valve - Google Patents

Description

  The present invention relates to a diaphragm valve, and more particularly to a diaphragm valve that is applied to a semiconductor manufacturing apparatus, a solar cell manufacturing apparatus, a liquid crystal manufacturing apparatus, and the like, and is mainly used in, for example, a gas supply system pipe.

Conventionally, on-off valves used in gas supply piping systems such as semiconductor manufacturing equipment, solar battery manufacturing equipment, and liquid crystal manufacturing equipment have been required to suppress the generation of particles with a small dead space. Valves are often used.
For example, a diaphragm valve 1 shown in FIG. 7 is known as this type of diaphragm valve. In this diaphragm valve 1, the valve seat 2 is attached by caulking to the body portion 3, and the diaphragm body 5 attached between the valve seat 2 and the pressing body 4 provided to be movable up and down is used as a pressing body. 4 is configured to be pressed against the valve seat 2 and sealed. On the body part 3 side, a concave mounting part 6 for accommodating the valve seat 2 is provided, and this concave mounting part 6 is shown in FIG. 1 as an inflow channel 7 and an outflow channel 8 provided in the body part 3. Is bent in the vertical direction to ensure its thickness.

On the other hand, the diaphragm valve 11 shown in FIG. 8 does not have a structure in which the valve seat is mounted on the body portion 12 side, but is attached so that the seal member 15 is suspended in the holder 14 mounted on the diaphragm body 13 side. It has been. In the diaphragm valve 11, the seal member 15 is sealed by being seated on the valve seat portion 16 formed on the body portion 12 side by the vertical movement of the holder 14, and fluid leakage to the outside and generation of particles are generated by the diaphragm body 13. Is prevented. In this case, the holder 14 and the diaphragm body 13 are joined by welding. In order to easily weld them, for example, stainless steel (for example, SUS316L) made of the same material as the holder 14 is used as the diaphragm body 13. Yes.
As a structure similar to the diaphragm valve 11, for example, a diaphragm type valve of Patent Document 1 is known. This valve is mounted in a state in which a metal diaphragm is fixed to a holder by welding and a sheet is suspended from the holder.

  These diaphragm valves are often used in a compound MO-CVD apparatus such as a semiconductor manufacturing apparatus. In the MO-CVD apparatus, it is frequently repeated that a plurality of gases having different properties are caused to flow or stop in the main flow path at different timings. Under this condition of use, the gas cannot be switched to the next gas or the like until the residue is reduced to a necessary concentration after the gas or the like previously flowed is stopped. Therefore, in order to minimize the switching timing of the flow path, it is important to minimize the volume from the valve seat to the main flow path.

Japanese Patent No. 4286934

  However, when the valve seat 2 is fixed to the body portion 3 side like the diaphragm valve 1 in FIG. 7, the thickness increases to accommodate the valve seat 2 and the vertical direction of the flow paths 7 and 8 is increased. The length of the bent portion becomes longer and the flow path volume of this portion becomes larger. As the volume of the vertical portion of the flow path increases in this way, the dead space increases and the fluid tends to remain, so that the flow path switching time becomes longer.

  On the other hand, the diaphragm valve 11 shown in FIG. 8 and Patent Document 1 has a structure in which the seal member 15 is mounted on the holder 14 side in FIG. 8, and compared with the diaphragm valve 1 in FIG. However, since the diaphragm body 13 and the holder 14 are integrated by welding, the durability of the diaphragm body 13 is reduced when the diaphragm body 13 is made of stainless steel, for example, and the valve opening / closing operation is performed. The number of possible times may be as few as tens of thousands. In order to avoid this, a Co-Ni alloy may be used as a highly durable diaphragm material. However, since the Co-Ni alloy and the stainless steel material are different materials, it is difficult to firmly fix them by welding. difficult. On the other hand, it is conceivable to form both the diaphragm and the holder with a Co—Ni alloy. However, it is economical to produce a large holder 14 with an expensive Co—Ni alloy as compared with the diaphragm body 13. Is not realistic.

Also, considering the effect of durability on diaphragm operating speed, stainless steel diaphragm has lower material strength and cannot operate faster than Co-Ni alloy diaphragm. Becomes longer.
Furthermore, when exchanging the diaphragm body 13, it is necessary to align the lifting and lowering parts such as the holder 14 and the stem 19 with the diaphragm body 13 using a dedicated jig. It becomes difficult.

The present invention has been developed in view of the conventional problems, and the object of the present invention is to change the flow path by minimizing the volume of the residual portion of the fluid when the valve is closed and minimizing the residual fluid. Speed can be of, have been, to improve the durability achieving long life, replacement of the diaphragm is also to provide an easy diaphragm valve.

In order to achieve the above object, according to the first aspect of the present invention, in the valve chamber provided in the valve box, a seat holder that holds a flat-shaped sheet in the lower portion, and the seat holder are detachably screwed. A diaphragm suspension type diaphragm in which the outer peripheral edge of the inner diameter hole is sandwiched between the diaphragm piece and the sheet holder, and the flat lower surface of the sheet has a minimal protrusion length. An annular protrusion is provided, and a flat valve seat surface for opening and closing the annular protrusion by contacting and separating the annular protrusion is provided in the valve chamber, and the valve box is provided immediately below the valve opening of the valve seat surface and the valve It has a main flow path arranged in the direction intersecting the mouth direction, and when the valve is closed, the volume from the flat lower surface of the seat to the communication path that communicates with the main flow path through the annular protrusion is minimal. Diamond configured to Is Ramubarubu.

  The invention according to claim 2 is a diaphragm valve in which a plurality of valve chambers of a block body are communicated by the main flow path, and a diaphragm suspension type diaphragm valve is provided in each of the valve chambers to form a multiple valve.

  Therefore, according to the present invention, there is no need to provide a seat accommodating portion on the valve box side, and the flow rate can be switched at a high speed by suppressing the residual fluid by providing the volume of the communication portion to a minimum.

  In addition, according to the present invention, even if there is a nonconformity or failure due to defective seats or seat caulking in one place of the multiple valve, there is no need to remanufacture the whole, and only the necessary diaphragm structure is replaced. In addition, if rubbing or scratching occurs near the valve seat and seal performance deteriorates, it is possible to polish and correct the vicinity of the valve seat by removing the diaphragm structure at that position, The entire block body is not exchanged, and man-hours and waste of materials can be reduced.

It is principal part sectional drawing which shows 1st Embodiment of the diaphragm valve of this invention. It is a partially notched front view which shows a diaphragm structure. It is a partially expanded sectional view of FIG. It is principal part sectional drawing which shows 2nd Embodiment of the diaphragm valve of this invention. It is a top view which shows an adjustment member. It is principal part sectional drawing which shows 3rd Embodiment of the diaphragm valve of this invention. It is a longitudinal cross-sectional view which shows an example of the conventional diaphragm valve. It is a longitudinal cross-sectional view which shows the other example of the conventional diaphragm valve.

  Embodiments of a diaphragm valve according to the present invention will be described below in detail with reference to the drawings. 1 shows a first embodiment of the diaphragm valve of the present invention, FIG. 2 shows a diaphragm structure, and FIG. 3 shows a partially enlarged sectional view of FIG.

  In the figure, the diaphragm valve has a valve box 20 formed of a metal material such as stainless steel, a diaphragm structure 21 mounted in the valve box 20, and an actuator body 22, and the diaphragm structure 21 is connected to the actuator body 22. The valve can be opened and closed by operating with.

  A main channel 23 and a plurality of communication channels 24 are formed in the valve box 20. The main flow path 23 is formed in the longitudinal direction of the central position of the valve box 20, and a communication flow path 24 is formed in communication with the main flow path 23 in the intersecting direction.

A valve seat surface 25 is provided on the inner bottom surface provided in the valve chamber 25b between the main flow path 23 and the communication flow path 24 provided in the valve box 20, and this valve seat surface 25 is attached to a seat 26 described later. Since it is not a side, it is formed on a flat bottom surface. The main flow path 23 is disposed via a communication portion 29 having a minimum volume V immediately below the valve opening 25a of the valve seat surface 25, and a diaphragm structure 21 in which the seat 26 is held in the valve box 20 by the seat holder 33. Is installed. The diaphragm valve is configured to open and close by opening and closing the seat 26 on the surface of the valve seat 25, and to supply fluid from each communication channel 24 to the main channel 23 while controlling the flow rate. A female screw 27 and a mounting recess 28 are formed on the diaphragm structure 21 mounting side of the valve box 20, and a mounting hole 20 a for mounting the heater is formed in parallel with the main flow path 23.

In FIG. 2, the diaphragm structure 21 includes a diaphragm 31, a diaphragm piece 32, a seat holder 33, a seat 26, a bonnet 34, a stopper 40, and a spring 41.
The diaphragm 31 is made of a dissimilar metal from the diaphragm piece 32 and the sheet holder 33, which are joining portions for joining the diaphragm 31. For example, the diaphragm 31 is formed into a disk shape by an elastically deformable metal material such as a Co—Ni alloy material. An inner diameter hole 51 for attachment through which a later-described male screw portion 35 of the sheet holder 33 is inserted is formed in the center portion. As shown in FIG. 3, the diaphragm 31 has a two-layer structure of a gas contact diaphragm 31a and a backup diaphragm 31b, which are integrally bonded and integrated.

  The diaphragm piece 32 is made of a metal material such as stainless steel such as SUS304, and is attached to the hood 34 so that the diaphragm 31 and the seat holder 33 can be moved up and down in the valve seat direction. The diaphragm piece 32 has a substantially cylindrical shape, and a female thread portion 37 is provided at the center of the bottom surface. The female thread portion 37 can be screwed with the thread portion 35 of the sheet holder 33.

An annular projecting portion 42 is formed on the lower side of the diaphragm piece 32. On the other hand, a shaft portion 32a is provided on the upper side, and a male screw 38 is formed on the shaft portion 32a. A stopper 40 is screwed onto the male screw 38 via a female screw 39. Between the stopper 40 and the bonnet 34, a spring 41 for biasing the seat holder 33 in the valve opening direction it is incorporated. The spring 41 is made of, for example, a metal material such as stainless steel such as SUS304-WPB, and the spring 41 forcibly biases the sheet holder 33 to which the diaphragm piece 32 and the seat 26 are attached until the spring 41 is opened.

  The stopper 40 is made of, for example, a metal material such as stainless steel such as SUS304, and applies a predetermined load to the spring 41 by screwing the female screw 39 to the male screw 38 described above. The stopper 40 can be attached and detached with a spanner or the like (not shown). By changing the mounting height of the stopper 40, the load of the spring 41 can be changed to adjust the urging force of the diaphragm piece 32 and the seat holder 33. ing.

  The sheet holder 33 is made of, for example, a metal material such as stainless steel such as SUS316L, and has a male screw part 35 screwed into the female screw part 37 and a diameter-enlarging part for attaching a sheet member having a diameter larger than that of the male screw part 35. 43. A mounting portion 44 for mounting the seat 26 is provided on the valve seat side of the enlarged diameter portion 43, and the diaphragm piece 32 protrudes on the diaphragm piece 32 side of the enlarged diameter portion 43 in order to achieve a metal seal structure with the diaphragm 31. A crushing seal portion 45 sandwiched between the installation portion 42 is formed in a ring-like shape.

  The sheet 26 is made of, for example, a resin material and is attached to the mounting portion 44 of the sheet holder 33 by caulking. An annular protrusion 46 that can contact the valve seat 25 is formed on the front end side of the seat 26, and the annular protrusion 46 is pressed against the valve seat 25 to be in a valve-closed state. From the mounting portion 44 to the tip end side of the annular protrusion 46, the protrusion length is extremely small in the fluid flow direction. This protrusion length (not shown) is a joint portion from the valve seat 25 to the main flow path 23 described later. This contributes to the minimum volume V.

  The bonnet 34 is formed with a metal material such as stainless steel such as SUS304 so as to fit into the mounting recess 28 of the valve box 20, and is mounted on the inner peripheral side so as to be movable up and down while guiding the diaphragm piece 32. A restricting portion 48 that abuts against the possible guide hole 47 and the diaphragm piece 32 and restricts its raised position is formed.

  The diaphragm structure 21 is configured such that the seat holder 33 and the diaphragm piece 32 are screwed together to sandwich the outer peripheral edge 52 of the inner diameter hole 51 of the diaphragm 31, the diaphragm piece 32 is held by the bonnet 34 so as to be movable up and down, and The diaphragm 31 is assembled in a state in which the diaphragm 31 is urged in the opening direction by a spring 41 attached to the shaft portion 32a of the diaphragm piece 32. The spring 41 is configured to apply an appropriate load by a stopper 40 screwed to the shaft portion 32a, and the diaphragm 31 is suspended from the bonnet 34 and the valve box 20 by sandwiching the outer peripheral edge 53 of the outer periphery side of the diaphragm 31. It is a structure.

  When the diaphragm 31 is attached, the shaft portion 32a is guided in a guide hole 47 formed in the bonnet 34 so as to be movable up and down, and one end side of the spring 41 is screwed to the bonnet upper surface 34a and the other end side is screwed to the upper portion of the shaft portion 32a. The diaphragm 31 is urged in the opening direction by coming into contact with the nut-shaped stopper 40 thus formed.

  In this case, the male screw portion 35 provided in the sheet holder 33 is passed through the inner diameter hole 51 of the diaphragm 31, and the seat holder is tightened by the screwing force between the male screw portion 35 and the female screw portion 37 of the diaphragm piece 32. The outer peripheral edge 52 of the inner diameter hole 51 of the diaphragm 31 is clamped by the crushing seal portion 45 of 33 and the protruding portion 42 of the diaphragm piece 32.

  The diaphragm 31 and the sheet holder 33 are detachably provided from the diaphragm piece 32. By removing the diaphragm structure 21 from the valve box 20, the diaphragm 31 and the seat holder 33 can be removed, and the diaphragm 31 and the seat 26 attached to the seat holder 33 can be exchanged.

  In FIG. 1, the actuator body 22 includes a casing 60, a cylinder member 61, an air piston 62, and a spring 63, and is attached to the upper side of the valve box 20 to which the diaphragm structure 21 is attached. The casing 60 has a male screw 64 that can be screwed to the female screw 27 on the lower side, and a housing hole 65 and a reduced-diameter through hole 66 that communicates with the housing hole 65 are provided on the inner periphery of the lower part. Yes. The upper side of the bonnet 34 can be inserted into the storage hole 65, and the diaphragm structure 21 is stored in the storage hole 65 by this insertion. The through hole 66 is provided with a diameter in which the lower side of the air piston 62 is fitted and the air piston 62 can reciprocate. A male screw portion 67 is provided on the upper outer periphery of the casing 60.

  The cylinder member 61 has a female screw portion 68 that can be screwed into the male screw portion 67, and is fixed to the upper portion of the casing 60 by screwing these together, so that the cylinder member 61 is placed between the cylinder member 61 and the casing 60. A space in which the air piston 62 can reciprocate is formed. The cylinder member 61 is provided with an air supply port 72 for supplying air and an exhaust port 71 for exhausting air. When air is supplied from the air supply port 72, the air piston 62 moves forward in the valve opening direction. At this time, the air on the spring 63 side of the cylinder member 61 is exhausted from the exhaust port 71. On the other hand, when the air supply from the air supply port 72 is stopped and exhausted, the air piston 62 is moved back in the valve closing direction by the spring 63. Thus, this diaphragm valve is NC (normally closed type).

The air piston 62 has a piston rod 69, which can reciprocate in the cylinder member 61 and the casing 60, and is mounted in a state where the bottom surface 69 a is pressed against the diaphragm piece 32 by a spring 63. Thereby, when the air piston 62 reciprocates, the diaphragm piece 32 moves up and down according to the operation of the air piston 62. The air piston 62 is provided with a through hole 73, and the through hole 73 communicates with the air supply port 72. When air is supplied from the air supply port 72, air is supplied to the primary side of the air piston 62 through the through hole 73, and the air piston 62 moves forward as described above.

  The spring 63 is mounted in an elastically biased state between the air piston 62 and the cylinder member 61. The spring 63 causes the air piston 62 to always operate the diaphragm piece 32 and the seat holder 33 in the closing direction. Be energized.

The actuator body 22 is screwed to the valve box 20 on the mounting side of the diaphragm structure 21 with a male screw 64 and a female screw 27. At this time, the lower end portion 22a of the actuator main body 22 presses and fixes the bonnet 34. As described above, since the air piston 62 and the spring 63 are built in the actuator body 22, the lower end 69 a of the piston rod 69 comes into contact with the upper end 32 b of the shaft portion of the diaphragm piece 32. With this structure, the diaphragm piece 32 is moved up and down via the air piston 62, and the force for pressing the seat holder 33 against the valve seat surface 25 of the valve box 20 is urged to open and close the valve seat 25 surface by the contact and separation of the seat 26. It is possible to operate.

Next, the operation of the above-described embodiment of the diaphragm valve of the present invention will be described.
The diaphragm valve of the present invention is provided with a main flow path 23 via a communication portion 29 having a minimum volume V immediately below the valve port 25a of the valve seat surface 25 in the valve chamber 25b provided in the valve box 20, Since the diaphragm structure 21 holding the seat 26 with the seat holder 33 is mounted in the valve box 20, the dead space of the communication portion 29 is reduced to minimize the residual fluid at the time of switching the flow path. The switching time when opening and closing the valve can be shortened. For this reason, for example, when used in a compound MO-CVD apparatus, even when a plurality of gases having different properties are used, this gas can be quickly discharged, and the switching time of the flow path can be minimized, thereby enabling smooth switching.

  The diaphragm structure 21 is configured such that the seat holder 33 and the diaphragm piece 32 are screwed together to sandwich the inner peripheral hole outer periphery 52 so that the diaphragm piece 32 can be moved up and down by the bonnet 34 and attached to the shaft portion 32a. The diaphragm 31 is urged in the opening direction by the spring 41, and an appropriate load is applied to the spring 41 by the stopper 40. The diaphragm suspending type is formed by sandwiching the outer peripheral edge 53 in the bonnet 34 and the valve box 20. Therefore, the diaphragm 31 can be mounted without welding, and the lifetime can be extended by forming only the diaphragm 31 with a highly durable material.

  At this time, the inner diameter hole 51 of the diaphragm 31 is sandwiched between the diaphragm piece 32 and the seat holder 33, and the outer edge 53 of the diaphragm 31 is sandwiched between the bonnet 34 and the valve box 20, so that the diaphragm The diaphragm structure 21 can be easily attached without welding 31. When the diaphragm 31 is deteriorated, only the diaphragm 31 can be removed and replaced, which is excellent in economic efficiency. Moreover, the diaphragm structure 21 can be attached and detached without using a special jig, and the diaphragm 31 and the sheet 26 can be easily replaced. In addition, productivity is improved because there is no cost and labor caused by welding.

  When the diaphragm structure 21 is mounted, the male threaded portion 35 is passed through the inner diameter hole 51, and the diaphragm 31 is formed by the crushing seal portion 45 and the projecting portion 42 by the tightening force caused by the screwing of the male threaded portion 35 and the female threaded portion 37. Since the outer peripheral edge 52 of the inner diameter hole is sandwiched, high sealing performance is exhibited and leakage from the diaphragm 31 mounting portion is surely prevented.

  The diaphragm 31 is made of a different metal from the diaphragm piece 32 and the sheet holder 33, and the diaphragm 31 is formed of a Co—Ni alloy material, thereby achieving durability that is difficult to realize with a stainless steel diaphragm. Even when the opening / closing operation is performed once, there is no possibility that the diaphragm 31 is damaged, and it is possible to constitute a diaphragm valve capable of controlling the flow rate with high accuracy while extending the life.

4 and 5 show a second embodiment of the diaphragm valve of the present invention. In the following embodiments, the same parts are denoted by the same reference numerals and the description thereof is omitted.
In this embodiment, a female screw 81 is provided on a cylinder member 80 provided on the upper portion of the air piston 62, and an adjustment member 83 is screwed to the female screw 81 via a screw 82. An air supply port 84 for supplying air, a bottomed hole 85, and a screw hole 86 are provided on the upper surface side of the adjustment member 83, and a fixing screw 87 is screwed into the screw hole 86. On the lower side of the adjustment member 83, a guide hole 89 for slidably fitting the reduced diameter cylindrical portion 88 of the air piston 62 and an abutting contact with the distal end side of the enlarged diameter cylindrical portion 90 of the air piston 62 are provided. A contact portion 91 is formed.

  The adjustment member 83 is movable in the reciprocating direction of the air piston 62 by inserting and rotating an appropriate tool (not shown) into the bottomed hole 85. In this case, the screwing amount of the fixing screw 87 is adjusted to adjust the protruding amount of the tip portion toward the air piston 62, and the screwing amount of the adjusting member 83 to the cylinder member 61 is adjusted. Thus, the stroke of the diaphragm 31 can be suppressed by adjusting the stroke when the air piston 62 comes into contact with the contact portion 91 with the adjustment member 83 while the contact portion 91 is disposed at a predetermined position. In this case, for example, when the adjustment member 83 is rotated 1/2, it is preferable that the adjustment member 83 is screwed about 0.25 mm.

  With this configuration, when air is supplied from the air supply port 84 and the air piston 62 is lifted by the air pressure to open the valve, the uppermost position of the air piston 62 is brought into contact with the contact portion 91 of the adjustment member 83. It depends on the end. When the adjustment member 83 is tightened clockwise from this state, the uppermost position of the air piston 62 is lowered, the stroke from the closed state to the open state of the diaphragm 31 is suppressed, and the maximum flow rate of the valve is reduced. By adjusting the tightening amount of the adjustment member 83, the maximum flow rate by each diaphragm structure 21 attached to the valve box 20 is made uniform, or the amount of fluid such as material gas that flows in from each diaphragm structure 21 Can be appropriately adjusted to an optimum state. Furthermore, the opening / closing time can be appropriately adjusted by suppressing the stroke.

FIG. 6 shows a third embodiment of the diaphragm valve of the present invention.
In this embodiment, the valve box is a block body 94, the main flow path 23 and a plurality of communication flow paths 24 are provided in the block body 94, and a plurality of diaphragm structures 21 are attached to form a multiple valve 95. Is. In this multiple valve 95, it is possible to provide a mixed fluid by controlling the opening and closing of the diaphragm structure 21 with respect to the fluid flowing through the main flow path 23 and supplying a predetermined amount of fluid from the communication flow path 24 as appropriate. Become.

  In a normal multiple valve structure, if there is a non-conformity due to a defective seat or seat caulking even at one part of the valve, the body needs to be remanufactured. However, in this embodiment, the diaphragm structure 21 is attached to and detached from the seat. Since it is possible to deal with defects such as 26, it is not necessary to remanufacture the block body 94. In addition, as described above, since the seat 26 is mounted on the seat holder 33 side, even if the valve seat inside the block body 94 is rubbed and scratches, etc., the seal performance becomes incompatible, it can be easily repaired by processing such as polishing. Further, since the block body 94 can be repaired with a minimum of processing, waste of man-hours and materials can be suppressed.

20 Valve box 21 Diaphragm structure 22 Actuator body 22a Lower end 23 Main flow path 25 Valve seat surface 25a Valve port
25b Valve chamber 26 Seat 29 Communication portion 31 Diaphragm 32 Diaphragm piece 32a Shaft portion 32b Shaft top end 33 Seat holder 34 Bonnet 34a Top surface 35 Male thread portion 37 Female thread portion 40 Stopper 41 Spring 42 Projection portion 45 Collapse seal portion 47 Guide hole 51 inner diameter hole 52 inner diameter hole outer periphery 53 outer periphery 62 air piston 63 spring 69 piston rod 69a lower end 83 adjustment member 94 block body 95 multiple valve V volume

Claims (2)

In the valve chamber provided in the valve box, there is a seat holder that holds a flat sheet at the bottom, a diaphragm piece for detachably screwing the seat holder, and an inner diameter hole between the diaphragm piece and the seat holder. A diaphragm hanging type diaphragm sandwiching the outer peripheral edge of the sheet, and a flat lower surface of the seat is provided with an annular protrusion having a minimal protrusion length, and the annular shape is provided in the valve chamber. A flat valve seat surface for opening and closing the valve by bringing the protrusion into contact and separation is provided, and the valve box is disposed immediately below the valve port of the valve seat surface and in a direction crossing the valve port direction. The main flow path is configured to have a minimal volume from the flat lower surface of the seat to the communication path communicating with the main flow path through the annular protrusion when the valve is closed. Da Yafuramubarubu.
  The diaphragm valve according to claim 1, wherein a plurality of valve chambers of a block body are communicated with each other through the main flow path, and a diaphragm suspension type diaphragm valve is provided in each of the valve chambers to form a multiple valve.

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