Actuator and valve device using the same
11174949 · 2021-11-16
Assignee
Inventors
Cpc classification
F16K1/523
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16K31/122
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16K7/17
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16K31/1226
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F16K1/52
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
H01L21/67
ELECTRICITY
Abstract
To provide a valve device capable of easily and precisely adjusting a flow rate of a flowing fluid, and an actuator used in the valve device. The problem is solved by an actuator including pistons housed in a housing, a supply port of compressed air provided to a casing constituting the housing, and an adjustment member that is provided to a position separated from the supply port and regulates an upper limit position of possible movement of the piston that comes into contact with the adjustment member. The piston comes into contact with the adjustment member and is positioned in the upper limit position when compressed air is supplied through the supply port. The adjustment member s provided so as to allow adjustment of the upper limit position from outside the housing.
Claims
1. An actuator comprising: a piston housed in a housing; a supply port of a pressurized fluid provided to the housing; and a piston adjuster provided to the housing at a position separated from the supply port and including a regulating surface that regulates an upper limit position of possible movement of the piston, wherein the piston or a structure that moves along with the piston comes into contact with the regulating surface of the piston adjuster when the pressurized fluid is supplied through the supply port, and the piston is positioned in the upper limit position, the piston adjuster is provided so as to allow adjustment of the upper limit position from outside the housing, the piston adjuster comprises a lock that is operable from outside the housing and locks a position of the piston adjuster, and the lock locks a position of the piston adjuster by deforming the piston adjuster screwed into the housing.
2. The actuator according to claim 1, wherein the piston adjuster is provided so as to be directly accessible from outside the housing.
3. The actuator according to claim 1, wherein the lock comprises a threaded structure that is operable from outside the housing, is screwed into and adjusts the piston adjuster, and a position of the piston adjuster is finely adjusted by operating the threaded structure while the position of the piston adjuster is locked by the threaded structure.
4. The actuator according to claim 1, wherein the supply port and an access hole to access the piston adjuster are provided on a common surface of the housing.
5. A valve device comprising: a valve body that defines a flow path; a valve element to open and close the flow path of the valve body; a valve operator that operates the valve element and is moveably provided between a closed position where the valve element closes the flow path and an open position where the valve element opens the flow path, set in advance, in opening and closing directions that allow the valve element to open and close the flow path; and the actuator as defined in claim 1 that is connected to the valve body at the housing and drives the valve operator, wherein the open position of the valve element is regulated in accordance with the upper limit position and adjusted by the piston adjuster.
6. A flow adjustment method of the valve device as defined in claim 5, comprising: raising the valve element to the open position while supplying a pressurized fluid to the actuator; and adjusting the flow rate of a fluid flowing through the flow path of the valve body by operating the piston adjuster.
7. A lift amount adjustment method of the valve device as defined in claim 5, comprising: adjusting a lift amount of the valve element from the closed position to the open position by the piston adjuster with the valve element raised to the open position while supplying a pressurized fluid to the actuator.
8. A flow control method comprising: adjusting a flow rate of a fluid using the valve device as defined in claim 5.
9. A fluid control system comprising: a plurality of fluid devices arranged from an upstream side toward a downstream side, each provided with the valve device as defined in claim 5.
10. A semiconductor manufacturing system that uses the valve device as defined in claim 5 to control a process gas in a manufacturing process of a semiconductor device that requires a treatment process by the process gas in a sealed chamber.
11. A semiconductor manufacturing method comprising: using the valve device as defined in claim 5 to control a flow rate of a process gas in a manufacturing process of a semiconductor device that requires a treatment process by the process gas in a sealed chamber.
12. The actuator according to claim 1, wherein the piston adjuster includes a columnar body including a slit disposed transverse to an axial direction of the columnar body, and the slit is provided so that an upper region of the columnar body is cantilever supported.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DESCRIPTION OF THE PREFERRED EMBODIMENTS
(14) Embodiments of this disclosure are described below with reference to the drawings. In the descriptions, the same elements are denoted using the same reference signs, and duplicate descriptions are omitted as appropriate.
(15) First, an example of a fluid control system in which the present invention is applied will be described with reference to
(16) In the fluid control system illustrated in
(17) Here, “fluid device” is a device used in a fluid control system for controlling a flow of a fluid, comprising a body defining a fluid flow path, and provided with at least two flow path ports that open on a surface of this body. Specifically, the fluid device includes the switch valve (two-way valve) 991A, the regulator 991B, the pressure gauge 991C, the switch valve (three-way valve) 991D, the mass flow controller 991E, and the like, but is not necessarily limited thereto. It should be noted that an introducing pipe 993 is connected to each of the flow path ports on the upstream side of the flow paths (not illustrated) described above.
(18) The present invention, while applicable to various valve devices such as the switch valves 991A, 991D, and the regulator 991B described above, will be described using a case of application to a switch valve as an example in this embodiment.
(19)
(20) The valve body 2 is formed from stainless steel into a block shape, and forms a first flow path 21 and a second flow path 22. A cylindrical part 24 is formed on an upper part side of the valve body 2, and an inner circumference of the cylindrical part 24 is formed into a screw hole 25 that is screwed with the bonnet 5. The first flow path 21 is a flow path that opens on a bottom surface of the valve body 2 and a bottom surface of the cylindrical part 24, and the second flow path 22 is a flow path that opens on the bottom surface of the valve body 2 and the bottom surface of the cylindrical part 24.
(21) The valve cent AR is disposed nn an opening periphery of the first flow path 21 of the bottom surface in the cylindrical part 24 of the valve body 2. The valve seat 48 may be made of a synthetic resin, such as perfluoroalkoxy alkane (PFA), polyamide (PA), polyimide (PI), polychlorotrifluoroethylene (PCTFE), or polytetrafluoroethylene (PTFE). The valve seat 48, while fixed to the valve body 2 by caulking, can also be disposed without caulking. An annular groove 23 is formed on the bottom surface of the cylindrical part 24, and this annular groove 23 and the second flow path 22 are interconnected.
(22) The diaphragm 41 is supported at a peripheral edge part on a lower side by a support part 26 having a stepped shape and formed inside the cylindrical part 24 of the valve body 2, and the diaphragm 41 is fixed to the valve body 2 with the peripheral edge part on an upper side of the diaphragm 41 opposite to the support part 26 pressed in the downward direction A2 by the pressing adapter 43 having an annular shape. In this embodiment, the diaphragm 41 is obtained by swelling central parts of a thin plate made of a metal such as a special stainless steel, and a nickel and cobalt alloy thin plate upward, and thus has a spherical shell shape in which an upwardly convex arc shape is the natural state. The diaphragm 41 is formed in an elastically deformable manner into a spherical shell shape by a metal such as stainless or an NiCo-based alloy, or a fluorine-based resin, for example. The diaphragm 41 interconnects and blocks the first flow path 21 and the second flow path 22 by moving between a closed position of contact and an open position of non-contact with the valve seat 48.
(23) The bonnet 5 is formed into a cylindrical shape, the outer peripheral surface on a lower end side of the bonnet 5 is screwed into the screw hole 25 of the valve body 2 to be connected to the valve body 2, and the lower end part of the bonnet 5 presses the pressing adapter 43 in the downward direction A2. It should be noted that a configuration in which the pressing adapter 43 is omitted and the peripheral edge part of the diaphragm 41 is pressed by the bonnet 5 is also possible.
(24) In the interior of the bonnet 5, the pressing holder 44 serving as an operation member is pressed by the coil spring 45 in the downward direction A2 relative to the bonnet 5, that is, in the direction in which the diaphragm 41 is moved to the closed position. While the coil spring 45 is used in this embodiment, the present invention is not necessarily limited thereto, and other types of elastic members can be used, such as a disc spring or a leaf spring. The diaphragm presser 42 that is made of a synthetic resin such as polyimide and comes into contact with a center upper surface of the diaphragm 41 is mounted on a lower end surface of the pressing holder 44. The diaphragm presser 42 and the pressing holder 44 function as the operation member of the present invention.
(25) The casing 6, the upper bulkhead 86 connected to the casing 6, the bonnet 5 connected to the upper bulkhead 86, and a lower bulkhead 84 sandwiched between the upper bulkhead 86 and the bonnet 5 form a housing of the actuator 8 that houses an upper piston 81A and a lower piston 81B.
(26) The upper piston 81A is disposed in a cylinder 83 formed between the upper bulkhead 86 and the lower bulkhead 84, and the lower piston 81B is disposed in the cylinder 83 sandwiched between the bonnet 5 and the lower bulkhead 84.
(27) A stem part 81Bt of the lower piston 81B is connected to the pressing holder 44.
(28) Seal rings 91 are disposed and secure airtightness between the bonnet 5, the lower piston 81B, the lower bulkhead 84, the upper piston 81A, the upper bulkhead 86, and the casing 6. A thread part 68 is formed on a lower side of an access hole 61 opening at a central part of the casing 6, and an adjustment member 7 described later is screwed into this thread part. The seal ring 91 is disposed and secures airtightness between the adjustment member 7 and the access hole 61 of the casing 6.
(29) A supply port 64 for supplying compressed air CA serving as the pressurized fluid is formed in a position separated from the access hole 61 on the upper part of the casing 6, the supply port 64 communicates with a flow path 62 formed in the casing 6, and the flow path 62 communicates with a flow path 63 formed between the casing 6 and the upper bulkhead 86. The supply port 64 and the access hole 61 are open on an upper surface which is a common surface of the casing 6. The flow path 63 communicates with a flow path 82 formed inside the upper piston 81A and the lower piston 81B. Here, the pressurized fluid is fluid pressurized by pressure sufficiently higher than atmospheric pressure, allowing the pistons to be driven against atmospheric pressure.
(30) The cylinder 83, the upper piston 81A, and the lower piston 81B constitute the actuator 8 that moves the pressing holder 44 and the diaphragm presser 42 to the open position against the coil spring 45. The actuator 8 increases the area on which pressure acts by using the plurality of upper and lower pistons 81A, 81B, making it possible to boost the force resulting from the compressed air CA.
(31) A so-called one-touch joint 100 is screwed into the supply port 64 of the casing 6, and the area between the one-touch joint 100 and the supply port 64 is sealed by the seal ring 91. The compressed air CA supplied through the one-touch joint 100 is supplied to the cylinder 83 between the upper piston 81A and the lower bulkhead 84 and to the cylinder 83 between the lower piston 81B and the bonnet 5 through the flow paths 62, 63, 82, and presses the upper piston 81A and the lower piston 81B in the upward direction A1. The upper piston 81A and the lower piston 81B are in contact with each other, and move in the upward and downward directions A1, A2 in coordination.
(32) A contact surface 7g of the adjustment member 7, which is the lower end surface, is brought into contact with an upper end surface 81a of a stem part 81At of the upper piston 81A and regulates an upper limit position P1 of possible movement of the upper piston 81A. The contact surface 7g is formed in a direction orthogonal to the upward and downward directions A1, A2, which are the movement directions of the pistons. The upper limit position of possible movement of the lower piston 81B is also regulated in accordance with the upper limit position P1. Further, the lower limit positions of possible movement of the upper piston 81A and the lower piston 81B are determined in accordance with the position of the valve seat 48 since the actuator 8 is connected to the valve body 2.
(33) That is, the lower limit positions of possible movement of the upper piston 81A and the lower piston 81B of the actuator 8 unit do not necessarily match those in a state in which the actuator 8 is assembled in the valve device 1.
(34) The adjustment member 7, as illustrated enlarged in
(35) In the adjustment member 7, the slit 7s is formed in the middle of the region where the thread part 7c is formed, and thus an upper region 7a of the adjustment member 7 is supported in a cantilevered fashion. As described later, by elastically deforming a base portion of the upper region 7a by the lock screw 75, a relative positional relationship between the portion corresponding to the upper region 7a of the thread part 7c and the thread part 68 of the casing 6 is changed, and the adjustment member 7 is prevented from rotating relative to the thread part 68 of the casing 6. That is, the lock mechanism is configured, in which the lock screw 75 elastically deforms the cantilevered upper region 7a defined by the slit 7s of the adjustment member 7, to thereby inhibit the rotation of the adjustment member 7 relative to the thread part 68. It should be noted that the lock mechanism is not limited to this, and may be a mechanism capable of inhibiting the rotation of the adjustment member 7 relative to the thread part 68.
(36) As illustrated in
(37)
(38) As illustrated in
(39) Next, an example of the flow adjustment method and the lift amount adjustment method of the valve device 1 will be described with reference to
(40) The valve device 1 illustrated in
(41) Next, the tool 300 configured by a flathead screwdriver is inserted into the access hole 61 of the casing 6 and engaged with the engaging groove 7t of the adjustment member 7, and the adjustment member 7 is rotated to move in the downward direction A2. When the adjustment member 7 is moved in the downward direction A2, the lift amount of the diaphragm 41 also decreases, the flow rate of the gas being monitored decreases, and the adjustment member 7 is rotated until it approaches a target flow rate When the flow rate of the gas being monitored reaches the target flow rate, the operation of the adjustment member 7 is stopped.
(42) Next, as illustrated in
(43) Fine Adjustment by Lock Screw
(44) As described above, when the force acting on the adjustment member 7 of the lock screw 75 exceeds a certain degree of force, the adjustment member 7 is locked.
(45) In this locked state, when the lock screw 75 is operated, the adjustment member 7 is subjected to slight elastic deformation. Utilizing the slight elastic deformation, after the adjustment member 7 is locked by the lock screw 75, fine adjustment of the flow rate or fine adjustment of the lift amount is possible by further operating the lock screw 75.
(46) Another example of the flow adjustment method and the lift amount adjustment method will now be described.
(47) In a valve device 1B illustrated in
(48) While, as described using
(49) In this state, the adjustment member 7 is adjusted while monitoring the detection value of the position sensor 200. When the position of the upper piston 81A in the upward and downward directions reaches the target position, that is, the position corresponding to the target lift amount, the adjustment member 7 is completely adjusted and locked by the lock screw 75.
(50) According to such a method, it is not necessary to introduce actual gas, making it possible to more easily implement the adjustment task.
(51) Next, an application example of the valve device 1 described above will be described with reference to
(52) A semiconductor manufacturing system 980 illustrated in
(53) In the semiconductor manufacturing process based on the ALD method, the flow rate of the process gas needs to be precisely adjusted and a certain amount of flow rate needs to be secured by increasing a size of a diameter of the substrate.
(54) The gas box 982 is an integrated gas system (a fluid control system) in which various fluid control devices, such as a switch valve, a regulator, and a mass flow controller, are integrated and housed in a box to supply an accurately measured process gas to the processing chamber 985.
(55) The tank 983 functions as a buffer for temporarily storing the process gas supplied from the gas box 982.
(56) The control unit 984 controls flow adjustment by controlling the supply of the operation gas to the valve device 1.
(57) The processing chamber 985 provides a sealed treatment space for forming a film on the substrate by the ALD method.
(58) The exhaust pump 986 draws a vacuum inside the processing chamber 985.
(59) It should be noted that the present invention is not limited to the aforementioned embodiments. Those skilled in the art can make various additions and modifications within the scope of the present invention. For example, while a case where the valve device 1 is used in a semiconductor manufacturing process based on the ALD method is illustrated in the above-described application example, the present invention is not necessarily limited thereto, and can be applied to various targets that require precise flow adjustment, such as an atomic layer etching (ALE) method, for example.
(60) While a piston built into a cylinder activated by gas pressure is used as the actuator in the above-described embodiment, the present invention is not necessarily limited thereto, and optimal actuators can be variously selected in accordance with the control target.
(61) While, in the configuration of the above-described embodiment, the valve device 1 is disposed outside the gas box 982 serving as a fluid control system, the valve device 1 of the above-described embodiment can also be included in fluid control system that integrates and houses various fluid devices such as a switch valve, a regulator, and a mass flow controller in a box.
(62) While the valve device is mounted on the plurality of flow path blocks 992 as a fluid control system illustrated in the above-described embodiment, in addition to the divided-type flow path block 992, the valve device of the present invention can also be applied to an integrated flow path block and a base plate.
(63) Although a case in which the piston and the stem of the actuator are integrally formed has been described as an example in the above-described embodiment, in a type of actuator in which the piston and the stem are separately formed and both the piston and the stem move when pressurized fluid such as compressed gas is supplied, the upper limit position of the piston can be regulated by the adjustment member coming into contact with the stem instead of the piston.
DESCRIPTIONS OF REFERENCE NUMERALS
(64) 1, 1B: Valve device
(65) 2: Valve body
(66) 5: Bonnet
(67) 6: Casing
(68) 7: Adjustment member
(69) 7a: Upper region
(70) 7c: Thread part
(71) 7d: Screw hole
(72) 7e: Cylindrical surface
(73) 7f1: Opposing surface
(74) 7f2: Opposing surface
(75) 7g: Contact surface (Regulating surface)
(76) 7s: Slit
(77) 7t: Engaging groove
(78) 8: Actuator
(79) 21: First flow path
(80) 22: Second flow path
(81) 23: Annular groove
(82) 24: Cylindrical part
(83) 25: Screw hole
(84) 26: Support part
(85) 41: Diaphragm
(86) 42: Diaphragm presser
(87) 43: Pressing adapter
(88) 44: Pressing holder
(89) 45: Coil spring
(90) 48: Valve seat
(91) 61: Access hole
(92) 62: Flow path
(93) 63: Flow path
(94) 64: Supply port
(95) 68: Thread part
(96) 75: Lock screw
(97) 75b: Hexagonal hole
(98) 75a: Thread part
(99) 75c: Lower end surface
(100) 81A: Upper piston
(101) 81At: Stem part
(102) 81B: Lower piston
(103) 81Bt: Stem part
(104) 81a: Upper end surface
(105) 82: Flow path
(106) 83: Cylinder
(107) 84: Lower bulkhead
(108) 86: Upper bulkhead
(109) 91: Seal ring
(110) 100: One-touch joint
(111) 200: Position sensor
(112) 300: Tool
(113) 400: Tool
(114) 980: Semiconductor manufacturing system
(115) 982: Gas box
(116) 983: Tank
(117) 984: Control unit
(118) 985: Processing chamber
(119) 986: Exhaust pump
(120) 991A to 991E: Fluid device
(121) 992: Flow path block
(122) 993: Introducing pipe
(123) A: Circle
(124) A1: Upward direction
(125) A2: Downward direction
(126) BS: Base plate
(127) C1: Arrow
(128) CA: Compressed air
(129) G1: Longitudinal direction upstream side
(130) G2: Longitudinal direction downstream side
(131) P0: Initial upper limit position
(132) P1: Upper limit position
(133) R: Reaction force
(134) W1: Width direction
(135) W2: Width direction
(136) X1: Reference plane
(137) X2: Plane