JP4347878B2 - Air operated valve - Google Patents

Description

  The present invention relates to an air operated valve in which a piston is slid in a cylinder by pressure of operating air, and a valve body is brought into contact with or separated from a valve seat.

  For example, air operated valves 1100A and 1100B shown in FIGS. 13 and 14 are examples of air operated valves for sliding the piston in the cylinder by the pressure of the operating air and causing the valve body to contact or separate from the valve seat. The air operated valves 1100A and 1100B use parts other than the pistons 1121 and 1131 and the compression coil springs 1126 and 1136, and are assembled in a normally valve open state and a normally valve closed state, respectively.

  An air operated valve 1100A shown in FIG. 13 has a piston 1121 loaded between a lower casing 1101 and an upper casing 1102. The piston 1121 divides a space formed between the lower casing 1101 and the upper casing 1102 into a lower space 1103 and an upper space 1104. A compression coil spring 1126 is contracted in the lower space 1103, and an upward force is always applied to the piston 1121. The upper space 1104 communicates with an operation port 1105 provided in the upper casing 1102 via a downward passage 1106 for introducing compressed air, and is supplied with operation air. The lower casing 1101 is connected to a valve box 1110 in which a valve seat 1109 is provided between the fluid inflow channel 1107 and the fluid outflow channel 1108. The piston 1121 is configured such that the valve rod 1122 protrudes toward the valve box 1110 and applies a driving force to the diaphragm 1112 via the disk 1111.

  Therefore, when operating air is not supplied to the operating port 1105, the air operated valve 1100A is assembled in a normally open state in which the piston 1121 is lifted by the elastic force of the compression coil spring 1126 and the diaphragm 1112 is separated from the valve seat 1109. ing. In the air operated valve 1100A, when operating air is supplied to the operating port 1105, the piston 1121 moves according to the balance between the internal pressure of the upper space 1104 and the elastic force of the compression coil spring 1126, and the diaphragm 1112 moves through the valve seat 1109. Abut.

  An air operated valve 1100B shown in FIG. 14 has a piston 1131 loaded between a lower casing 1101 and an upper casing 1102. The piston 1131 includes an upper small-diameter portion 1133 inserted into the downward passage 1106 for introducing compressed air, in addition to the valve rod 1132. The piston 1131 has a compressed air passage 1134 formed along the axis from the center of the upper end surface of the upper small diameter portion 1133, and extends radially from the lower end of the compressed air passage 1134 so as to communicate with the lower space 1103. Is formed. A seal member 1113 is attached to the outer peripheral surface of the upper small-diameter portion 1133 in order to seal the space between the inner peripheral surface of the downward passage 1106 for introducing compressed air, so that the operating air does not flow into the upper space 1104. A compression coil spring 1136 is contracted in the upper space 1104, and a downward force is always applied to the piston 1131.

  Therefore, when operating air is not supplied, the air operated valve 1100B is assembled in a normally closed state in which the piston 1131 is pushed down by the elastic force of the compression coil spring 1136 and the diaphragm 1112 is brought into contact with the valve seat 1109. In the air operated valve 1100B, when operating air is supplied to the operating port 1105, the operating air is supplied to the lower space 1103 via the compressed air passage 1134 and the radial passage 1135 of the piston 1131, and the elastic force of the compression coil spring 1136 is supplied. The piston 1131 rises according to the balance between the inner pressure of the lower space 1103 and the diaphragm 1112 is separated from the valve seat 1109.

  As described above, the air operated valves 1100A and 1100B can change the normal valve open state and the normal valve close state only by changing the pistons 1121 and 1131 and the compression coil springs 1126 and 1136. You can go down.

JP 2004-92824 A

  However, the air operated valves 1100A and 1100B have different shapes of the pistons 1121 and 1131, and the pistons 1121 and 1131 cannot be used in common. The pistons 1121 and 1131 are large and have a special shape. Therefore, the conventional air operated valves 1100A and 11000B have a problem in that the processing and management of the pistons 1121 and 1131 are expensive.

  Therefore, the present invention has been made to solve the above problems, and an object thereof is to provide an inexpensive air operated valve.

The air operated valve according to the present invention has the following configuration.
(1) In an air operated valve that applies a driving force to the valve portion by sliding the piston in the cylinder by operating air pressure and moving the piston rod connected to the piston back and forth to the valve portion side, A piston structure in which a first piston rod that advances and retreats to the valve portion side in the closed state and a second piston rod that advances and retreats to the valve portion side in the normally open state are provided in opposite directions across the piston portion Have

(2) In the invention according to (1), the piston structure intersects the first piston rod in a direction intersecting with the axis and the second piston rod intersecting with the axis. A second branch channel formed in a direction and a bypass channel formed in the axial direction of the piston and communicating the first branch channel and the second branch channel, and is always in a valve-open state And a sealing member that is attached to the bypass channel and blocks between the first branch channel and the second branch channel.

(3) In the invention described in (2), when the piston structure is normally in a valve-closed state, a seal member is attached to the first piston rod and the second piston rod. A seal member is attached to the second piston rod, and no seal member is attached to the first piston rod.

(4) In the invention according to any one of (1) to (3), the cylinder has a hollow exterior member and a cylindrical shape that opens on one side, and the interior component is loaded into the exterior member. The interior parts are combined to form a piston chamber in the exterior member, and the piston is disposed in each piston chamber.

(5) In the invention according to any one of (1) to (4), the biasing member mounted in the cylinder when the valve is normally closed is placed inside the cylinder when the valve is normally open. The biasing force is larger than the biasing member to be mounted.

  In the invention described in (1) above, by reversing the piston, a driving force is applied to the valve portion by the first piston rod in the normally closed state, and a driving force is applied to the valve portion by the second piston rod in the normally open state. Therefore, it is possible to configure a normally valve closed state and a normally valve open state using the same piston. Therefore, according to the invention described in (1) above, it is possible to reduce the cost by using a piston in addition to the cylinder.

  In the invention described in (2) above, the communication state between the first branch flow path formed in the first piston rod and the second branch flow path formed in the second piston rod is established, and the sealing member is attached to and detached from the bypass flow path. Therefore, the internal flow path configuration when the piston is inverted can be changed only by the sealing member attached to the bypass flow path, and the processing cost and management cost of the piston can be reduced.

  In the invention described in (3) above, the seal member is attached to the first and second piston rods when the valve is normally closed, and the seal member is attached only to the second piston rod when the valve is always open. Since the seal member is not attached to the first piston rod, if the seal member is attached to and detached from the first piston rod, the same piston can be reversed and used in the normally closed state and the normally open state. Processing costs and management costs can be reduced.

  In the invention described in the above (4), the piston chambers are formed in the exterior member by combining the interior parts having the same shape and arranged in the exterior member, and the piston is accommodated in each piston chamber. An arbitrary number of piston chambers can be formed by combining the parts to accommodate the pistons, and the number of cylinders processed can be reduced to reduce costs.

  In the invention described in (5) above, the biasing force of the biasing member mounted in the cylinder when the valve is normally closed is greater than the biasing force of the biasing member mounted within the cylinder when the valve is always open. Therefore, it is possible to easily equalize the load acting on the valve portion by making the valve closing force substantially the same in the normally valve closed state and the normally valve opened state.

Next, an embodiment of an air operated valve according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of an air operated valve 1 according to an embodiment of the present invention. FIG. 2 is a top view of the air operated valve 1 shown in FIG.
The air operated valve 1 of the present embodiment includes a piston rod 42 that is an example of a “first piston rod” that moves forward and backward when the valve is normally closed, and a valve portion 2 when the valve is always open. It has a feature in that it has a piston structure in which a piston rod 52 that is an example of a “second piston rod” that moves forward and backward is provided in an opposite direction with piston parts 41 and 51 that are examples of a “piston part” interposed therebetween. .

<Overall configuration>
An air operated valve 1 shown in FIG. 1 is a normally closed type (hereinafter referred to as “NC type”) valve, and includes a valve unit 2 that controls a control fluid, and an actuator unit 3A that applies a driving force to the valve unit 2. With. The air operated valve 1 has a cylindrical appearance by connecting the actuator portion 3A to the body 4 via the adapter 11.

  The valve unit 2 is built in the body 4. The body 4 is formed of a metal material having rigidity and heat resistance, such as stainless steel or aluminum, in a cylindrical shape. A primary side port 5 and a secondary side port 6 are provided on the lower surface of the body 4. On the other hand, a mounting hole 7 is formed in a cylindrical shape on the upper side surface of the body 4. A valve seat 8 is provided in an annular shape at the center of the bottom wall of the mounting hole 7, and the primary side port 5 and the secondary side port 6 communicate with each other through the valve seat 8.

  The valve portion 2 has an adapter 11 in which a diaphragm 9 is mounted in the mounting hole 7 of the body 4, the outer edge portion of the diaphragm 9 is pressed by the holder 10, and inserted between the inner peripheral surface of the mounting hole 7 and the outer peripheral surface of the holder 10. Is screwed into the body 4 so that the outer edge of the diaphragm 9 is held between the body 4 and the holder 10. The diaphragm 9 is made of a thin film made of resin or metal so that it can be deformed. The holder 10 and the adapter 11 are made of a metal having heat resistance and rigidity. The holder 10 is loaded with a metal stem 13 so as to come into contact with the diaphragm 9, and the driving force of the actuator portion 3 </ b> A is transmitted to the diaphragm 9 via the stem 13.

  The actuator portion 3A has a cylindrical shape as shown in FIGS. As shown in FIG. 1, the actuator portion 3A has an NC type air cylinder structure. The actuator unit 3A is configured by dividing a cylinder that houses the pistons 23 and 24 into a plurality of parts, specifically, an exterior member 21, an interior part 22, a base 25, and a cap 26.

  As shown in FIG. 1, the actuator portion 3A is configured by alternately loading interior parts 22A, 22B, and 22C and pistons 23 and 24 in a pipe-shaped exterior member 21, and attaching a base 25 and a cap 26 to both ends of the exterior member 21. By attaching, the interior parts 22A, 22B, and 22C are sandwiched and held between the base 25 and the cap 26. Therefore, the interior parts 22 </ b> A, 22 </ b> B, and 22 </ b> C are fixed in a state of being overlapped inside the exterior member 21, and form a first piston chamber 27 and a second piston chamber 28. The pistons 23 and 24 are slidably loaded in the first and second piston chambers 27 and 28, and the first and second piston chambers 27 and 28 are made into pressure chambers 27a and 28a and back pressure chambers 27b and 28b. Each is divided. In the back pressure chamber 28b of the second piston chamber 28, a compression spring 29A, which is an example of an “urging member” that is mounted in the cylinder when the valve is normally closed, is contracted, and the pistons 23 and 24 are arranged at the bottom in the figure. The force in the direction (valve seat direction) is always applied.

  The actuator portion 3A is fixed to the body 4 via the adapter 11. Therefore, the pistons 23 and 24 may not be arranged coaxially with respect to the valve seat 8 depending on the dimensions of parts and assembly variations. However, the pistons 23 and 24 transmit driving force to the diaphragm 9 via the columnar stem 13. Therefore, even when the position where the piston 23 abuts on the stem 13 is slightly deviated from the axis, the stem 13 is in surface contact with the diaphragm 9 and transmits the driving force in a distributed manner. It can be brought into close contact with a uniform force in the circumferential direction.

  The air operated valve 1 is supplied and exhausted with operating air via an air supply / exhaust port 85 provided at the center of the upper end surface of the cap 26. The supply / exhaust port 85 communicates with the pressurizing chambers 27a, 28a of the first and second piston chambers 27, 28 via internal flow paths (described later) formed in the pistons 23, 24. Further, the air operated valve 1 has back pressure chambers 27b, 28b of the first and second piston chambers 27, 28 between the inner peripheral surface of the exterior member 21 and the outer peripheral surfaces of the interior components 22A, 22B, 22C. A plurality of conduction channels 31 for communicating with the breathing holes 12 formed in the adapter 11 are formed. Accordingly, in the air operated valve 1, the pistons 23 and 24 move in the axial direction according to the balance between the elastic force (repulsive force) of the compression spring 29A and the internal pressure of the pressurizing chambers 27a and 28a, and the valve portion 2 The driving force can be transmitted to.

  Next, components constituting the cylinder of the air operated valve 1 will be described.

<Piston configuration>
3 is a central longitudinal sectional view of the piston 23 and the piston 24 shown in FIG.
Pistons 23 and 24 are made by injection-molding a heat-resistant and lightweight resin such as PPS (polyphenylene sulfide), PBT (polybutylene terephthalate), POM (polyacetal), PA (polyamide), PVDF (polyvinyl fluoride), etc. It is a molded product.

  The piston 23 is formed by integrally forming a piston rod 42 and a piston rod 43 in the piston portion 41. The piston portion 41 has a columnar shape, and the outer diameter dimension is substantially the same as the inner diameter dimension of the interior part 22. A mounting groove 44 for mounting a sealing member 33 (see FIG. 1) such as an O-ring made of an elastic material such as rubber or resin is annularly provided in the piston portion 41 along the outer peripheral surface. The piston rods 42 and 43 also have mounting grooves 45 and 46 for mounting sealing members 32 and 34 (see FIG. 1) such as O-rings made of an elastic material such as rubber or resin along the outer peripheral surface. It is provided in a ring shape.

  As shown in FIGS. 1 and 3, the piston 23 is provided with a T-shaped internal flow path including a main flow path 47 and a branch flow path 48 that is an example of a “first branch flow path”. . The main flow path 47 is formed from the center of the end face of the piston rod 43 to the branch flow path 48 along the axis. The branch channel 48 corresponds to the pressurizing chamber 27 a and is provided between the mounting groove 45 of the piston rod 42 and the base end portion where the piston rod 42 connects to the piston portion 41. The branch channel 48 is formed so as to penetrate in the radial direction of the piston rod 42. The branch channel 48 has a rectangular shape with a wide cross section.

  On the other hand, the piston 24 is obtained by integrally forming a piston rod 52 in the piston portion 51. The piston portion 51 has a cylindrical shape, and the outer diameter dimension is substantially the same as the inner diameter dimension of the interior part 22. A mounting groove 53 for mounting a sealing member 35 (see FIG. 1) such as an O-ring made of an elastic material such as rubber or resin is annularly provided in the piston portion 51 along the outer peripheral surface. The piston rod 52 has substantially the same shape as the piston rod 42 of the piston 23 so that when the pistons 23 and 24 are reversed, the piston rod 52 is inserted into the base 25 and can transmit a driving force to the diaphragm 9 via the stem 13. . A mounting groove 54 for mounting a seal member 36 (see FIG. 1) such as an O-ring made of an elastic material such as rubber or resin is annularly provided on the piston rod 52 along the outer peripheral surface.

  As shown in FIGS. 1 and 3, the piston 24 is provided with a T-shaped internal flow path including a main flow path 55 and a branch flow path 56 which is an example of a “second branch flow path”. . The main channel 55 is formed from the center of the end surface of the piston portion 51 to the branch channel 56 along the axis. The branch flow path 56 corresponds to the insertion hole 81 of the cap 26 and is provided on the distal end side from the mounting groove 53 of the piston rod 52. Therefore, the distance from the piston part 51 of the branch flow path 56 is longer than the distance from the piston part 41 of the branch flow path 48 provided in the piston 23. The branch flow path 56 is formed so as to penetrate in the radial direction of the piston rod 52. The branch channel 56 has a rectangular shape with a wide cross section.

The piston 24 is provided with a fitting recess 57 concentrically with the main channel 55 at the opening of the main channel 55. A communication passage 58 is formed in a band shape on the bottom wall of the fitting recess 57, and a part of the operation air flowing through the main flow path 55 is guided to the fitting recess 57 via the communication passage 58.
The piston 24 is provided with a guide portion 59 by expanding the base end portion of the piston rod 24. The guide portion 59 is inserted into the compression spring 29A and is provided to stably expand and contract the compression spring 29A in the axial direction.

  Such pistons 23 and 24 are opposed to the pistons 42 and 52 with the piston portions 41 and 51 interposed therebetween by fitting the piston rod 43 of the piston 23 into the fitting recess 57 of the piston 24 and bringing the end surfaces into contact with each other. It is provided in the direction. The main flow path 55 of the piston 24 and the main flow path 47 of the piston 23 communicate with each other to form a “bypass flow path” that connects the branch flow paths 48 and 56.

<Composition of interior parts>
Interior parts 22A, 22B, and 22C shown in FIG. 1 are resin molded products obtained by injection molding a resin having heat resistance and rigidity, such as PPS, PBT, POM, PA, and PVDF. Since the interior parts 22A, 22B, and 22C have the same shape, the interior part 22B will be described here for convenience of description, and the description of the interior parts 22A and 22C will be omitted.

  As shown in FIG. 1, the interior part 22 </ b> B has a bag shape opened to one side. The interior part 22B has a side surface formed in a cylindrical shape, and is provided with a closed end surface so as to close one end opening of the side surface. The interior part 22 </ b> B has an outer diameter that is substantially the same as the inner diameter of the exterior member 21, and the inner diameter of the side surface corresponds to the piston portion 51. The side surface of the interior component 22B is supported by being in contact with and supported by the inner peripheral surface of the exterior member 21 when the interior component 22B is loaded on the exterior member 21. On the other hand, the closed end face of the interior part 22B includes a partition plate that partitions the hollow portion of the exterior member 21 to form the first and second piston chambers 27 and 28 when the interior part 22B is loaded into the exterior member 21. Therefore, it is made thick so as to ensure pressure resistance against the operation air.

FIG. 4 is an external perspective view of the interior component 22B shown in FIG.
The interior part 22B is provided with a through hole 61 through the piston rod 43 of the piston 23 (in the case of the interior parts 22A and 22B, the piston rods 42 and 52) in the center of the closed end face. An annular groove 62 is formed concentrically with the through hole 61 on the outer surface of the closed end face. A plurality of guide grooves 63 are formed on the outer surface of the closed end surface so as to be longer in the outer diameter direction from between the through hole 61 and the annular groove 62. A D-cut passage 64 is formed on the outer peripheral surface of the interior part 22 </ b> B in parallel with the axis so as to continue from the guide groove 63. The interior part 22 </ b> B has a notch 65 formed so as to be continuous with the D-cut passage 64 at the opening end of the side surface.

<Configuration of exterior member, base, cap>
As shown in FIG. 1, the base 25 and the cap 26 are caulked and fixed at both ends of the exterior member 21, and constitute the appearance of the actuator portion 3 </ b> A. The metal exterior member 21, the base 25, and the cap 26 surround the resin interior parts 22A, 22B, and 22C and complement the strength of the interior parts 22A, 22B, and 22C.

5 is a cross-sectional view showing the relationship among the cap 26, the base 25, and the exterior member 21 shown in FIG.
The exterior member 21 has a cylindrical shape with both ends open. The exterior member 21 is formed by forming a metal having rigidity such as stainless steel into a thin pipe shape by drawing or extruding, and cutting the drawn tube or the extruded tube to a predetermined length. The total length of the exterior member 21 is determined by how many piston chambers are provided by overlapping the interior components 22. Further, the thickness of the exterior member 21 is determined in consideration of pressure resistance against the operation air. In this embodiment, it is 0.5 mm.

<Base cap>
The base 25 and the cap 26 close both ends of the exterior member 21 so that the interior components 22A, 22B, and 22C are stacked and accommodated in the exterior member 21 against the elastic force of the compression spring 29A. A space (gap) is formed inside. The cap 26 and the base 25 abut against the closed end surfaces of the interior parts 22A and 22C and support the interior parts 22A and 22C. Therefore, the base and cap 26 have a cylindrical shape made of a rigid metal such as stainless steel or aluminum.

  The base 25 has a columnar shape whose outermost diameter is the same as or larger than the outer diameter of the exterior member 21, and is provided with a connecting hole 71 penetrating in the center. A female screw for screwing a male screw provided on the outer peripheral surface of the adapter 11 is formed on the inner peripheral surface of the connecting hole 71. On one end surface of the base 25, a positioning recess 72 for positioning the interior component 22A is provided coaxially with the connecting hole 71. A press-fitting portion 73 having a press-fitting allowance is provided on the outer periphery of the end surface where the positioning recess 72 is formed in order to press-fit the open end portion of the exterior member 21. Further, on the outer peripheral surface of the base 25, a caulking groove 74 for caulking the end portion of the exterior member 21 to deform inward is formed inside the press-fit portion 73.

  The cap 26 has a cylindrical shape whose outermost diameter is the same as or larger than the outer diameter of the exterior member 21. The cap 26 has an insertion hole 81 formed in a columnar shape at the center of one end surface. The insertion hole 81 is formed so that the piston rod 52 of the piston 24 can be inserted without contact. A mounting groove 82 for mounting a sealing member 37 (see FIG. 1) such as an O-ring made of an elastic material such as rubber or resin is annularly provided around the insertion hole 81 on one end face of the cap 26. Yes. The mounting groove 82 corresponds to the annular groove 62 of the interior part 22C. A press-fitting portion 83 having a press-fitting allowance is provided on the outer periphery of one end surface of the cap 26 in order to press-fit the open end portion of the exterior member 21. A caulking groove 84 for caulking the end of the exterior member 21 and deforming it inwardly is formed on the outer peripheral surface of the cap 26 inside the press-fit portion 83. The cap 26 is provided with an air supply / exhaust port 85 so as to communicate with the insertion hole 81 from the center of the other end surface.

<How to assemble an air operated valve>
Next, an example of a method for assembling the air operated valve 1 including the above components will be described.
First, the valve seat 8 is fixed to the mounting hole 7 of the body 4, and the diaphragm 9 is set in the mounting hole 7. Then, the holder 10 is inserted into the mounting hole 7 of the body 4 so as to hold the outer edge of the diaphragm 9, and the stem 13 is fitted into the holder 10, and then the adapter 11 is screwed into the body 4 and fixed. Thereby, the valve part 2 is assembled.

  Then, the actuator unit 3A is assembled. Seal members 32, 33, 34, 35, and 36 are mounted in the mounting grooves 44, 45, 46, 53, and 54 of the pistons 23 and 24, respectively. Then, the press-fit portion 73 of the base 25 is press-fitted into the one end opening of the exterior member 21. Then, the exterior member 21 is loaded with the interior component 22A, the piston 23, the interior component 22B, the piston 24, the compression spring 29A, and the interior component 22C. At this time, the piston rod 42 of the piston 23 is passed through the through hole 61 and the base 25 of the interior part 22A. Then, the cap 26A is fitted to the opening end of the exterior member 21 so as to pass through the piston rod 52 protruding outward from the through hole 61 of the interior part 22C, and the annular groove 62 of the interior part 22C and the mounting groove 82 of the cap 26, The press-fitting portion 83 of the cap 26 is press-fitted into the opening of the other end of the exterior member 21 so as to crush the seal member 37. At this stage, the interior parts 22A, 22B, 22C, the pistons 23, 24, and the compression spring 29A are temporarily held in the exterior member 21. Then, both end portions of the exterior member 21 are fixed by caulking along the caulking grooves 74 and 84 of the base 25 and the cap 26.

  Thereafter, the actuator part 3 </ b> A is connected to the valve part 2. That is, the adapter 11 screwed on the body 4 is screwed into the connection hole 71 of the base 25. At this time, the piston rod 42 of the piston 23 protruding outward from the base 25 hits the stem 13, and the elastic force of the compression spring 29 </ b> A acting on the pistons 23 and 24 is transmitted to the diaphragm 9 via the stem 13. Is brought into contact with the valve seat 8. This completes the assembly.

<Channel structure>
The flow path structure of the air operated valve 1 assembled as described above will be described. FIG. 6 is a diagram showing the flow path structure of the air operated valve 1 shown in FIG.
The air supply / exhaust port 85 is connected to the pressurizing chamber 27a of the first piston chamber 27 through the insertion hole 81 of the cap 26, the branch channel 56 of the piston 24, the main channel 55, the main channel 47 of the piston 23, and the branch channel 48. Communicate. The supply / exhaust port 85 communicates with the pressurizing chamber 28a of the second piston chamber 28 through the insertion hole 81 of the cap 26, the branch channel 56 of the piston 24, the main channel 55, the communication channel 58, and the fitting recess 57. is doing.

  As described above, in the air operated valve 1, a flow path for supplying and exhausting operation air to and from the pressurizing chambers 27 a and 28 a is formed by the flow paths 47, 48, 55 and 56 provided in the pistons 23 and 24. .

  Further, the air operated valve 1 allows the back pressure chambers 27b and 28b of the first and second piston chambers 27 and 28 to be connected to one breathing hole 12 provided in the adapter 11, as indicated by dot hatching in the drawing. The conduction channel 31 is provided.

  The interior parts 22A, 22B, and 22C form a space with the exterior member 21 by the D-cut passage 64 formed on the outer peripheral surface. The back pressure chamber 27b of the first piston chamber 27 communicates with the space provided by the D-cut passage 64 of the interior part 22A via the notch 65 of the interior part 22A and the guide groove 63 of the interior part 22B. The back pressure chamber 28b of the second piston chamber 28 communicates with a space provided by the D-cut passage 64 of the interior parts 22B and 22C via a notch 65 provided in the interior parts 22B and 22C.

  A gap is formed between the closed end face of the interior part 22A and the base 25 by an annular groove 62 and a guide groove 63 provided in the interior part 22A. The gap communicates with a space formed between the interior parts 22A, 22B, 22C and the exterior member 21, and communicates with a hollow hole provided in the adapter 11. A breathing hole 12 is formed in the adapter 11 so as to communicate with the hollow hole.

  As described above, the air operated valve 1 includes the space formed between the interior parts 22A, 22B, and 22C, the space formed between the interior parts 22A, 22B, and 22C and the exterior member 21, and the interior part 22A. A space formed between the base 25 and the base 25 forms a conduction channel 31 for communicating the back pressure chambers 27b, 28b of the first and second piston chambers 27, 28 to the breathing hole 12 of the adapter 11. .

<Operation explanation of NC type air operated valve>
Next, the operation of the air operated valve 1 according to this embodiment will be described.
The air operated valve 1 is installed and fixed by inserting a bolt (not shown) through a mounting hole 14 provided in the body 4 as shown in FIG. 2, and fastening the bolt to a mounting plate or a semiconductor manufacturing apparatus. Is done. The air operated valve 1 has an air supply / exhaust port 85 connected to an air supply / exhaust control device (not shown) via an air supply / exhaust pipe (not shown) to control supply / exhaust of operation air.

  When the operating air is not supplied to the air supply / exhaust port 85, the air operated valve 1 causes the pistons 23 and 24 to be pushed down toward the valve seat by the elastic force of the compression spring 29A, and the diaphragm 9 is moved to the valve seat 8 via the stem 13. Make contact. Therefore, the control fluid supplied to the primary side port 5 does not flow from the valve seat 8 to the secondary side port 6.

  Thereafter, when operating air is supplied to the air supply / exhaust port 85, the operating air is added to the first piston chamber 27 via the branch flow path 56, the main flow path 55, the main flow path 47, and the branch flow path 48 of the piston 23. It is supplied to the pressure chamber 27a. Further, the operation air is supplied to the pressurizing chamber 28 a via the branch flow path 56, the main flow path 55, the communication path 58, and the fitting recess 57 of the piston 24. When the pressurizing chambers 27a and 28a are pressurized and overcome the elastic force of the compression spring 29A, the pistons 23 and 24 push the air from the back pressure chambers 27b and 28b to the conduction channel 31 and exhaust the air from the breathing hole 12. The piston rod 42 is smoothly raised in the middle-up direction (the direction opposite to the valve seat 8), and the piston rod 42 is separated from the stem 13. As a result, the diaphragm 9 is not pressurized in the valve seat direction and is separated from the valve seat 8 by its own reaction force. When the control fluid is supplied to the primary port 5 in this state, the control fluid flows from the primary port 5 to the secondary port 6 through the valve seat 8.

  After that, when the operating air of the pressurizing chambers 27a and 28a is discharged from the air supply / exhaust port 85 and the elastic force of the compression spring 29A becomes larger than the internal pressure of the pressurizing chambers 27a and 28a, the pistons 23 and 24 descend and the piston rod 42 is abutted against the stem 13, and a force in the valve seat direction is applied to the diaphragm 9 through the stem 13. At this time, since air is supplied from the breathing hole 12 to the back pressure chambers 27b and 28b through the conduction channel 31, the pistons 23 and 24 are smoothly lowered. When the diaphragm 9 abuts on the valve seat 8 and blocks the flow path, the control fluid does not flow from the valve seat 8 to the secondary port 6.

(NC-NO change)
Next, the case where the air operated valve 1 shown in FIG. 1 is a normally open type (hereinafter referred to as “NO type”) will be described. FIG. 7 is a sectional view of the NO type air operated valve 1.

  The air operated valve 1 is shown in FIG. 1 in a state where the seal member 32 is removed from the piston rod 42, the compression spring 29A is replaced with the compression spring 29B, and a stopper plug 90 is attached to the main flow path 55 of the piston 24. The interior parts 22A, 22B, 22C of the actuator part 3A and the pistons 23, 24 are integrally inverted and arranged in the exterior member 21, thereby configuring the NO type actuator part 3B shown in FIG.

  That is, the air operated valve 1 is formed by laminating an interior part 22C, a piston 24, an interior part 22B, a piston 23, and an interior part 22A in order from the lower side on the exterior member 21, and the upper and lower ends of the exterior member 21 are connected to the cap 26. The actuator portion 3B is configured by caulking and fixing to the base 25. In the air operated valve 1, a compression spring 29 </ b> B, which is an example of an “urging member” that is mounted in the cylinder when the valve is always open, is compressed in the back pressure chamber 28 b of the second piston chamber 28.

  Since the compression spring 29B only needs to secure a force necessary to separate the piston 24 from the stem 13, the compression spring of the air operated valve 1 is set so that the valve closing force is almost the same as that in the normally closed state. A material having a smaller elastic force (biasing force) than 29A is used. In such an air operated valve 1, the pistons 23 and 24 are pushed up by the elastic force of the compression spring 29 </ b> B, and the piston rod 52 is separated from the stem 13. Therefore, the diaphragm 9 is not given a force in the valve seat direction.

  The piston 23 is loaded in the cylinder in a state where the seal member 36 is mounted in the mounting groove 54 of the piston rod 55 and the seal member 32 is not mounted in the mounting groove 45 of the piston rod 42. The piston 23 provides a gap between the outer peripheral surface of the piston rod 42 and the inner peripheral surface of the insertion hole 81 by inserting the piston rod 42 to which the seal member 32 is not attached into the insertion hole 81 of the cap 26. The supply / exhaust port 85 communicates with the pressurizing chamber 27a of the first piston chamber 27 through the gap.

  On the other hand, the piston 24 is disposed such that the piston rod 52 is inserted into the connecting hole 71 of the base 26 and can be advanced and retracted to the valve portion 2 side. In the piston 24, a stopper plug 90 having a spherical shape of a steel ball or an elastic member is press-fitted into the main flow path 55, and the main flow path 55 is airtightly closed. Therefore, the air supply / exhaust port 85 of the cap 26 is connected to the pressurizing chamber of the second piston chamber 28 from the insertion hole 81 through the branch flow path 48 of the piston 23, the main flow path 47, the communication path 58 of the piston 24, and the fitting recess 57. It communicates with 28a.

  In the NO type air operated valve 1 as well, a plurality of electrical connections are made between the interior parts 22A, 22B, 22C and the exterior member 21 by the D-cut passages 64 formed on the outer peripheral surfaces of the interior parts 22A, 22B, 22C. A flow path 31 is formed, and the back pressure chambers 27 b and 28 b of the first and second piston chambers 27 and 28 are connected to the breathing hole 12.

<Operation explanation of NO type air operated valve>
In such an air operated valve 1, when operating air is not supplied to the air supply / exhaust port 85, the piston 24 and the piston 23 are pushed up by the elastic force of the compression spring 29B. Therefore, the diaphragm 9 is not pressurized in the valve seat direction via the stem 13 and is separated from the valve seat 8 by its own reaction force. When the control fluid is supplied to the primary port 5 in this state, the control fluid supplied to the primary port 5 flows to the secondary port 6 through the valve seat 8.

  On the other hand, when operating air is supplied to the air supply / exhaust port 85, the operating air is supplied from the insertion hole 81 to the pressurizing chamber 27a of the first piston chamber 27, and the branch flow of the piston 23 from the insertion hole 81. The pressure is supplied to the pressurizing chamber 28a of the second piston chamber 28 through the passage 48, the main channel 47, the communication passage 58 of the piston 24, and the fitting recess 57, and the pressurizing chambers 27a and 28a are pressurized. When the internal pressure of the pressurizing chambers 27a and 28a overcomes the elastic force of the compression spring 29B, the pistons 23 and 24 descend while exhausting air from the back pressure chambers 28b and 27b to the breathing hole 12 through the conduction channel 31. The piston rod 52 of the piston 24 is abutted against the stem 13 and a force in the valve seat direction is applied to the diaphragm 9 via the stem 13. When the diaphragm 9 comes into contact with the valve seat 8, the control fluid does not flow from the primary side port 5 to the secondary side port 6 via the valve seat 8.

  After that, when the operation air of the pressurizing chambers 27a and 28a is discharged from the air supply / exhaust port 85 and the elastic force of the compression spring 29B overcomes the internal pressure of the pressurizing chambers 27a and 28a, the pistons 23 and 24 rise and the stem 13 Separate from. At this time, air is supplied from the breathing hole 12 to the back pressure chambers 27b and 28b via the conduction channel 31, so that the pistons 23 and 24 rise smoothly. The diaphragm 9 is not pressurized in the valve seat direction, and is separated from the valve seat 8 by its own reaction force. Therefore, when the control fluid is supplied to the primary side port 5, the control fluid flows from the primary side port 5 to the secondary side port 6 through the valve seat 8.

<Effect>
When the air operated valve 1 is changed from the normally closed state to the normally opened state, the interior parts 22A, 22B, 22C and the pistons 23, 24 shown in FIG. Then, the stopper plug 90 is press-fitted from the opening of the main channel 55 of the piston 24 to seal the main channel 55, and the O-ring 32 is removed from the piston rod 42 of the piston 23. Then, the compression spring 29A is replaced with the compression spring 29B, and the pistons 23, 24 and the compression spring 29B are loaded between the interior parts 22A, 22B, 22C. Then, as shown in FIG. 7, the pistons 23, 24 are inverted together with the interior parts 22 </ b> A, 22 </ b> B, 22 </ b> C and are fitted into the exterior member 21. Make it protrude.

  The pistons 23 and 24 are pushed up by the compression spring 29B and held in the valve open position. The distance from the tip of the piston rod 52 to the seal member 36 is substantially the same as the distance from the tip of the piston rod 42 to the seal member 32, and the seal member 36 is provided inside the branch flow path 56. . Therefore, the air operated valve 1 in the normally open state does not cause fluid leakage because the seal member 36 does not fall off from the inner peripheral surface of the interior part 22C even when the pistons 23 and 24 are lowered. The valve can operate smoothly.

  On the other hand, when the air operated valve 1 is changed from the normally closed state to the normally opened state, the interior parts 22A, 22B, 22C and the pistons 23, 24 shown in FIG. Then, the stopper plug 90 is removed from the main flow path 55 of the piston 24, and the seal member 32 is attached to the piston rod 42 of the piston 23. Then, the compression spring 29B is replaced with the compression spring 29A, and the pistons 23, 24 and the compression spring 29A are loaded between the interior parts 22A, 22B, 22C. Then, as shown in FIG. 1, the pistons 23, 24 are inverted together with the interior parts 22 </ b> A, 22 </ b> B, 22 </ b> C and fitted into the exterior member 21, and the piston rod 42 of the piston 23 is passed through the through hole of the base 25 to the valve part 2 side. Make it protrude.

  The pistons 23 and 24 are pushed down by the compression spring 29A and held in the valve closed position. The seal member 32 of the piston rod 42 is disposed outside the mounting groove 48 so that the operation air can be supplied to the pressurizing chamber 27 a, and the distance from the tip of the piston rod 42 to the seal member 32 is the tip of the piston rod 52. To the seal member 36 is substantially the same. For this reason, the air operated valve 1 has a positional relationship in which the seal member 32 does not fall off the inner peripheral surface of the interior part 22A even when the pistons 23 and 24 are raised, so that no fluid leakage occurs and the valve operates smoothly. Can be done.

  In this way, the air operated valve 1 reverses the pistons 23 and 24 within the exterior member 21 to apply a driving force to the valve portion 2 by the piston rod 42 in the normally closed state (see FIG. 1). In the valve open state, a driving force is applied to the valve portion 2 by the piston rod 56 (see FIG. 7), so that it is possible to configure a normally valve closed state and a normally valve open state using the same pistons 23 and 24.

  Therefore, according to the air operated valve 1 of the present embodiment, in addition to the exterior member 21, the interior components 22A, 22B, 22C, 22D, the base 25, the cap 26, and the like constituting the cylinder, the pistons 23, 24 are shared. Cost can be reduced. Specifically, for example, the pistons 23 and 24 have a complicated and large shape. However, since the pistons 23 and 24 are commonly used for the valve-closed state and the valve-open state, the valve-closed state and the valve-opened state are always used. Compared to the case where separate pistons are used, the number of processes and material consumption can be reduced to reduce the processing cost, and the management cost can be reduced by narrowing the management space.

  In the air operated valve 1 of the present embodiment, the communication state between the branch flow path 48 formed in the piston rod 42 and the branch flow path 56 formed in the piston rod 52 is the main flow that constitutes a part of the “bypass flow path”. Since it can be changed by attaching and detaching the stopper plug 90 to the passage 55 (see FIGS. 1 and 7), the internal flow path configuration when the pistons 23 and 24 are reversed can be changed only by the stopper plug 90, and the piston 23 and 24 processing costs and management costs can be reduced.

  In the air operated valve 1 of the present embodiment, the seal members 32 and 36 are attached to the piston rods 42 and 52 when the valve is normally closed (see FIG. 1), and the piston rod 52 when the valve is always open. Since the seal member 36 is attached only to the piston rod 42 and the seal member 32 is not attached to the piston rod 42 (see FIG. 7), if the seal member 32 is attached to and detached from the piston rod 42, the same piston is used in both the normally closed state and the normally open state. 23 and 24 can be reversed and used, and the processing cost and management cost of the pistons 23 and 24 can be reduced.

  The air operated valve 1 of this embodiment forms piston chambers 27 and 28 in the exterior member 21 by combining the interior parts 22A, 22B, and 22C having the same shape and arranging them in the exterior member 21. Since the pistons 23 and 24 are accommodated in the cylinders 27 and 28 (see FIGS. 1 and 7), an arbitrary number of piston chambers 27 and 28 are formed by a combination of interior parts 22A, 22B and 22C having the same shape. 24 can be accommodated, and the number of cylinders can be reduced to reduce costs.

  In the air operated valve 1 of the present embodiment, the biasing force of the compression spring 29A mounted in the cylinder when the valve is normally closed is greater than the biasing force of the compression spring 29B mounted within the cylinder when the valve is normally open. Since it is large, the load acting on the valve seat 8 can be easily equalized by making the valve closing force substantially the same in the normally closed state and the normally opened state.

  Note that the present invention is not limited to the above-described embodiment, and various applications are possible.

(1) For example, in the above embodiment, the two-stage air operated valve 1 has been described. However, as shown in FIG. 8, three piston chambers 27, 28, 121 are formed by stacking four interior parts 22A, 22B, 22C, 22D having the same shape and fixing them in the exterior member 21, A three-stage air operated valve 1A can be configured. In this case, a convex piston 122 may be interposed between the pistons 23 and 24. The piston 122 may be formed with a main channel 123, a fitting recess 124 may be provided in the opening of the main channel 123, and a communication path 125 may be formed on the inner peripheral surface of the fitting recess 124. This is to make the air supply / exhaust port 85 communicate with the pressurizing chamber 28a of the piston chamber 28. If the number of pistons 122 disposed between the pistons 23 and 24 is changed, a four-stage or more air operated valve can be configured.

  Further, as shown in FIG. 9, two interior parts 22B and 22C having the same shape are stacked and fixed in the exterior member 21, thereby forming one piston chamber 28 and a one-stage air operated valve. 1B can be configured. In this case, it is preferable to provide two branch channels 128 and 129 in the piston 126 so as to communicate with each other via the main channel 127. This is because the supply / exhaust port 85 is communicated with the pressurizing chamber 28a of the piston chamber 28 via the branch channel 128, the main channel 127, and the branch channel 129.

  Therefore, as shown in the air operated valves 1A and 1B, it is possible to make any number of air operated valves just by changing the number of interior parts 22 to be stacked. Can do.

Further, for example, the air operated valve 1B shown in FIG. 10 replaces the compression spring 29A shown in FIG. 9 with the compression spring 29B, removes the seal member 32, and attaches a stopper plug 90 to the main flow path 127 of the piston 126. The interior parts 22B and 22C are changed from the NC type to the NO type by inverting the piston 126 together with the piston 126 in the axial direction in the exterior member 21. Therefore, also in this modified example, parts other than the compression springs 29A and 29B, the seal member 32, and the stopper plug 90 can be shared to change the type from the NC type, and the cost can be reduced.
In the air operated valve 1B shown in FIG. 8, the seal member 32 is removed, the compression spring 29A is replaced with the compression spring 29B, and the stopper plug 90 is attached to the main flow path 55 of the piston 24. If the parts 22A, 22B, 22C, 22D and the pistons 23, 24, 122 are integrally inverted and arranged in the exterior member 21, the NC type can be changed to the NO type.

(2) For example, in the above embodiment, the D-cut passage 64 is formed on the outer peripheral surface of the interior parts 22A, 22B, 22C, so that the conduction flow path is provided between the interior parts 22A, 22B, 22C and the exterior member 21. 31 was formed. On the other hand, as shown in FIG. 11, instead of the D-cut passage 64, a plurality of conductive grooves 131 having a rectangular cross section may be formed on the outer peripheral surfaces of the interior parts 22A, 22B, 22C. In this case, a conduction flow path 31 is formed between the conduction groove 131 of the interior part 22A, 22B, 22C and the inner peripheral surface of the exterior member 21. Further, the D-cut passage 64 is not provided on the outer peripheral surfaces of the interior parts 22A, 22B, and 22C, and as shown in FIG. 12, a conduction groove 132 is formed on the inner peripheral surface of the exterior member 21, and the interior parts 22 and the exterior member 21 are formed. A conduction channel 31 may be formed between the two. The conduction groove 132 can be formed together when the exterior member 21 is drawn or extruded, and the processing cost is low. Furthermore, the conduction groove 131 may be provided in the interior parts 22A, 22B, and 22C, and the conduction groove 132 may be provided in the exterior member 21.

(3) For example, in the above-described embodiment, both ends of the exterior member 21 are crimped and fixed after being press-fitted into the base 25 and the cap 26. However, the base 25 and the cap 26 are welded, press-fitted, adhered, and screw structure to the exterior member 21. It may be fixed by such as.

(4) In the above embodiment, the interior parts 22A, 22B, 22C and the pistons 23, 24 are made of resin molded products. However, such as aluminum die-cast molded products or lost wax molded products, the number of cutting processes is small and can be molded at low cost. You may comprise an interior part and a piston with a molded article. When the air operated valve 1 or 1B controls a high-temperature control fluid or is heated, the entire temperature exceeds 80 degrees, and the resin molded product is used as the interior parts 22A, 22B, 22C and the pistons 23, 24. May not be available. In this case, the interior parts 22A, 22B, 22C and the pistons 23, 24 are constituted by aluminum die-cast moldings or lost wax moldings, which are metal, even in an environment where the overall temperature exceeds the heat resistance temperature exceeding 80 degrees. It is preferable that the air operated valve 1 can be used.

(5) In the said embodiment, the shape of the branch flow paths 48 and 56 was made into the rectangular shape. The branch channel may have a channel cross-sectional area that is longer than the vertical dimension in the axial direction and longer than the horizontal dimension in the direction intersecting (orthogonal) with respect to the main channel. . Therefore, the channel cross-sectional shape of the branch channel may be an elliptical shape that is long in the lateral direction or a shape in which a plurality of round holes are connected in a circumferential direction of the piston rod.

(6) In the above embodiment, the driving force of the actuator portions 3 </ b> A and 3 </ b> B is transmitted to the diaphragm 9 via the stem 13. On the other hand, the diaphragm 9 may be fixed to the tip portions of the pistons 23 and 24 so that the driving force is directly transmitted to the diaphragm 9.

(7) In the above embodiment, the air operated valve 1 is a two-way valve that switches the communication state between the primary side port 5 and the secondary side port 6. On the other hand, you may apply the structure of actuator part 3A, 3B demonstrated in the said embodiment to multiway valves, such as a three-way valve. Moreover, although the air operated valve 1 of the said embodiment is a diaphragm valve, a poppet valve may be sufficient.

(8) In the above embodiment, the exterior member 21 is a metal pipe. On the other hand, the exterior member 21 may be a resin molded product.
(9) In the above embodiment, the outer diameter of the air operated valve 1 is a cylindrical shape, but the outer diameter may be a polygonal shape.
(10) In the above embodiment, the control fluid flows from the primary side port 5 to the secondary side port 6, but the control fluid may flow from the secondary side port 6 to the primary side port 5.

It is sectional drawing of the NC type air operated valve concerning the embodiment of the present invention. Similarly, it is a top view of the air operated valve shown in FIG. Similarly, it is the center longitudinal cross-sectional view of the 1st piston and 2nd piston which are shown in FIG. Similarly, it is an external appearance perspective view of the interior component shown in FIG. Similarly, it is sectional drawing which shows the relationship between the cap shown in FIG. 1, a base, and an exterior member. Similarly, it is an air operated valve shown in FIG. 1, and is a view showing a flow path structure. Similarly, it is sectional drawing of what deform | transformed the air operated valve shown in FIG. 1 into NO type | mold. It is a figure which shows the internal structure of a 3-stage type air operated valve of a normally closed type air operated valve of this invention. It is a figure which shows an internal structure when the air operated valve of a reference example is deform | transformed into the normally closed type 1 step | paragraph type air operated valve. FIG. 10 is a diagram showing an internal structure when the normally closed type one-stage air operated valve shown in FIG. 9 is changed to a normally open type. It is a figure which shows the modification of the interior components which comprise the air operated valve of a reference example . It is a figure which shows the modification of the exterior member which comprises the air operated valve of a reference example . It is sectional drawing of the conventional air operated valve, Comprising: A valve open state is always shown. It is sectional drawing of the conventional air operated valve, Comprising: A valve-closed state is always shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air operated valve 2 Valve part 21 Exterior member 22 Interior component 23 Piston 24 Piston 27 1st piston chamber 28 2nd piston chamber 29A, 29B Compression spring (biasing member)
32 Seal member 36 Seal member 41 Piston part 42 Piston rod (first piston rod)
47 Main channel (Bypass channel)
48 branch channel (first branch channel)
51 Piston part 52 Piston rod (second piston rod)
55 Main channel (Bypass channel)
56 Branch channel (second branch channel)
90 Stopper (sealing member)

Claims (6)

An air operated valve that applies driving force to the valve part by sliding the piston in the cylinder by the pressure of the operating air and moving the piston rod connected to the piston back and forth to the valve part side. in type air operated valve or constantly open valve type air operated valve, either a selectable air operated valve system,
The air operated valve is
A first piston and a second piston used in contact with each other;
When configuring the normally valve-closed air operated valve, the first piston is located on the valve portion side,
The air operated valve system is characterized in that when the normally valve-open air operated valve is configured, the second piston is positioned on the valve portion side. In the air operated valve used in the air operated valve system according to claim 1,
An air operated valve having a piston structure in which a first piston rod provided in the first piston and a second piston rod provided in the second piston are provided in opposite directions across a piston portion. In the air operated valve according to claim 2,
The piston structure is
A first branch passage formed in a direction intersecting the axis of the first piston rod; a second branch passage formed in a direction intersecting the axis of the second piston rod; and an axial direction of the piston A bypass channel formed to communicate the first branch channel and the second branch channel,
An air operated valve comprising: a sealing member that is attached to the bypass flow path and blocks between the first branch flow path and the second branch flow path when the valve is always open. In the air operated valve according to claim 3,
In the piston structure, when the valve is normally closed, a seal member is attached to the first piston rod and the second piston rod, while when the valve is always open, a seal member is attached to the second piston rod. A seal member is not attached to the first piston rod;
Air operated valve featuring In the air operated valve according to any one of claims 2 to 4,
The cylinder includes a hollow exterior member, a cylindrical shape that opens to one side, and an interior component that is loaded into the exterior member.
An air operated valve, wherein the interior parts are combined to form a piston chamber in the exterior member, and the piston is disposed in each piston chamber. In the air operated valve according to any one of claims 2 to 5,
An air operated valve characterized in that a biasing member mounted in the cylinder when the valve is normally closed has a biasing force greater than a biasing member mounted within the cylinder when the valve is always open.

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