Valve opening / closing speed reduction unit and valve device

Abstract

To provide a valve opening / closing speed reduction unit capable of reducing an opening / closing speed of a valve at low cost with a simple mechanism, and a valve device comprising the unit.SOLUTION: A unit for controlling operating air of an air-operated valve comprises a check valve mechanism (1) including: a check valve body 10 having a primary passage 13, a valve chamber 14, and a secondary passage 15 connected in series therein; a seal part 20 provided around an opening part of the primary passage 13 in the valve chamber 14; and a check valve body 30 that is movably or deformably provided in the valve chamber 14, and opens and closes between the primary passage 13 and the secondary passage 15 by moving away from or abutting against the seal part 20. The check valve body 30 or the check valve body 10 has a bypass flow path 50 that communicates the primary passage 13 and the secondary passage 15 and allows a small flow rate to flow even when the check valve body 30 abuts against the seal part 20.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a valve opening / closing speed reduction unit and a valve device using the same.

Background Art

[0002] In semiconductor manufacturing processes, particularly in fine processes such as ALD (Atomic Layer Deposition) and ALE (Atomic Layer Etching), various valve devices are used to supply a processing gas accurately metered in a short time to a processing chamber. Among these, for example, among the valves arranged on the primary side and the secondary side to open and close the line of a vaporizer, like the valve on the secondary side, in order to prevent gas from being trapped in the flow path after the line is closed, there may be cases where the closing operation is intentionally performed slowly.

[0003] As such, as a valve that performs the closing operation slowly, there is an air-operated valve that stores operating air not only in the pressure chamber of an air cylinder that drives the valve to open and close but also in a variable-volume pressure chamber, thereby lengthening the operating air exhaust time and slowing down the closing operation of the valve (Patent Document 1).

[0004] Also known is an air-operated valve having a valve-opening pressure chamber defined by a bellows-shaped diaphragm assembly and accommodating operating air. In this valve, immediately after the valve-opening signal, operating air is quickly introduced into the valve-opening pressure chamber from the pilot pressure passage and the pre-pressure passage. When the introduced operating air expands the valve-opening pressure chamber, the pre-pressure passage closes, and thereafter, the valve is configured to open slowly with operating air introduced only from the pilot pressure passage (Patent Document 2).

[0005] Also known is an air-operated valve including a first check valve that allows operating air to flow only in the input direction to the drive unit and a first needle valve driven by a motor, and a second check valve that allows operating air to flow only in the discharge direction from the drive unit and a second needle valve driven by a motor. By adjusting the opening degrees of these first needle valve and second needle valve with their respective motors, the valve opening speed and valve closing speed of the air-operated valve can be adjusted (Patent Document 3).

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, in the valves of Patent Document 1 and Patent Document 2, since a variable-volume storage chamber for temporarily storing operating air is provided in the housing, there is a problem that the valve mechanism becomes complicated and the size increases. Also, in the valve of Patent Document 3, since a motor for driving a needle valve that adjusts the flow rate of pilot air is provided, there is a concern that the structure is complicated and the cost is high.

[0008] One object of the present invention is to provide a valve opening / closing speed reduction unit that can reduce the opening / closing speed of a valve with a simple mechanism and low cost, and a valve device including the same.

Means for Solving the Problems

[0009] To solve the above problems, the valve opening / closing speed reduction unit of the present invention is a unit that controls the operating air of an air-operated valve, and includes a check valve body having a primary passage, a valve chamber, and a secondary passage connected in series inside, a seal portion provided around the opening of the primary passage in the valve chamber, and a check valve body movably or deformably provided in the valve chamber, which opens and closes between the primary passage and the secondary passage by separating from or contacting the seal portion. Even when the check valve body is in contact with the seal portion, a bypass flow path that allows the primary passage and the secondary passage to communicate with each other and allows a small flow rate to flow is provided in the check valve body or the check valve body. With this configuration, when the fluid flows from the primary passage to the secondary passage, the check valve mechanism opens and a large flow rate of fluid flows. When the fluid flows from the secondary passage to the primary passage, the check valve mechanism closes and only a small flow rate of fluid flows through the bypass flow path. By providing the valve opening / closing speed reduction unit with this simple structure in the operating air supply line of the air-operated valve, the speed of the closing operation or the opening operation of the valve can be reduced.

[0010] It is preferable that the primary passage, the valve chamber, and the secondary passage are arranged substantially coaxially in the check valve body and each have a circular cross section, and the diameter of the valve chamber is larger than the diameters of the primary passage and the secondary passage. With this configuration, the valve opening / closing speed reduction unit has a linear structure and can be coaxially attached to a drive actuator of a general air-operated valve, so it is easy to arrange in an integrated gas system or the like.

[0011] The check valve body forms a substantially bottomed cylindrical shape with one end closed, and is provided in the valve chamber coaxially with the valve chamber so as to be movable in the axial direction of the check valve body with the one end on the seal portion side. Preferably, the bypass flow path is provided by penetrating the one end in the axial direction of the check valve body. With this configuration, the valve opening / closing speed reduction unit can be realized by adding only slight processing to the check valve structure.

[0012] Alternatively, the bypass passage preferably comprises a first passage extending from the valve chamber in the direction of the outer peripheral portion, a second passage extending from the primary side passage in the direction of the outer peripheral portion, and a third passage communicating the first passage and the second passage, inside the check valve body. Even with this configuration, a valve opening / closing speed reduction unit can be realized by simply adding slight machining to the check valve structure. In addition, a flow rate adjustment mechanism may be provided in this bypass passage.

[0013] The check valve body preferably comprises an inner body having the primary side passage and the valve chamber inside and an outer peripheral thread portion on the outer peripheral portion, and an outer body having an inner peripheral thread portion screwed with the outer peripheral thread portion on the inner peripheral side and having the secondary side passage provided through the bottom, in a substantially bottomed cylindrical shape. With this configuration, the primary side passage, the valve chamber, and the secondary side passage coaxially arranged inside the check valve body can be easily formed.

[0014] Further, a configuration further having biasing means for biasing the check valve body toward the seal portion side can be preferably adopted. With this configuration, when the fluid flows from the secondary side passage to the primary side passage, the check valve mechanism is surely closed.

[0015] Further, the check valve body preferably has one or a plurality of through holes penetrating from the inner peripheral side to the outer peripheral side. With this configuration, even in a structure where the outer periphery on the other end side of the check valve body fits and slides with the inner periphery of the valve chamber, a fluid flow path is formed from the inner peripheral side of the check valve body through the through hole to the space inside the valve chamber, so that the check valve mechanism is maintained.

[0016] The check valve body comprises a central axis portion fixed coaxially with the valve chamber inside the valve chamber, an annular thin plate-shaped diaphragm portion extending from the outer peripheral side of the central axis portion, and an outer ring portion provided on the outer peripheral side of the diaphragm portion. Due to the elastic deformation of the diaphragm portion, the outer ring portion is configured to move away from or contact the seal portion to open and close between the primary side passage and the secondary side passage. Preferably, the bypass passage is a groove provided in at least one of the seal portion and the contact surface of the outer ring portion with the seal portion. With this configuration, even when the differential pressure between the primary side and the secondary side is small, the check valve function acts stably, and stable sealing performance can be obtained.

[0017] The check valve body preferably includes a top-opening cylindrical outer body having a primary side passage provided through the ceiling portion and an internal thread portion on the inner peripheral side, and an inner body having an external thread portion screwed with the internal thread portion on the outer peripheral side and having the secondary side passage inside. A valve chamber is formed between the ceiling portion and the inner body inside the outer body, and the central axis portion of the check valve body is fixed to the inner body. With this configuration, the primary side passage, the valve chamber, and the secondary side passage coaxially arranged inside the check valve body can be easily formed.

[0018] The valve device of the present invention further includes a valve device main body including a valve body, a valve element, and an air cylinder actuator for moving the valve element, and a valve opening / closing speed reduction unit connected to an operation air introduction hole of the air cylinder actuator. With this configuration, the speed of the closing operation or the opening operation of the valve can be reduced.

[0019] In the valve device, preferably, the valve opening / closing speed reduction unit is configured such that the secondary passage side is connected to the operation air introduction hole of the air cylinder actuator. In this case, if the valve device main body is of the normally closed type, only the speed of the closing operation can be reduced, and if the valve device main body is of the normally open type, only the speed of the opening operation can be reduced.

[0020] Alternatively, the valve opening / closing speed reduction unit may be configured such that the primary passage side is connected to the operation air introduction hole of the air cylinder actuator. In this case, if the valve device body is of the normally closed type, only the opening operation speed can be reduced, and if the valve device body is of the normally open type, only the closing operation speed can be reduced.

Advantages of the Invention

[0021] According to the present invention, by providing a valve opening / closing speed reduction unit with a simple structure in the operation air supply line of the air-operated valve, the speed of the closing operation or the opening operation of the valve can be reduced.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description, the same elements are denoted by the same reference numerals, and redundant descriptions are omitted as appropriate. (First Embodiment) FIG. 1 shows a valve opening / closing speed reduction unit 1 according to this embodiment. In FIG. 1, 10 is a check valve body, 20 is a seal portion, 30 is a check valve body, 40 is a coil spring (biasing means), and 50 is a bypass passage.

[0024] The check valve body 10 is a member having a primary side passage 13, a valve chamber 14, and a secondary side passage 15 connected in series therein. In this embodiment, the check valve body 10 has a primary side passage 13 and a valve chamber 14 inside, and an inner body 11 having an outer peripheral thread portion 11a on the outer peripheral portion, and an inner peripheral thread portion 12a that engages with the outer peripheral thread portion 11a on the inner peripheral side, and a substantially bottomed cylindrical outer body 12 provided with a secondary side passage 15 penetrating the bottom. The primary side passage 13, the valve chamber 14, and the secondary side passage 15 are arranged substantially coaxially in the check valve body 10 assembled in this way, each having a circular cross section, and the diameter of the valve chamber 14 is configured to be larger than the diameters of the primary side passage 13 and the secondary side passage 15. In this embodiment, the primary side passage 13 and the secondary side passage 15 are formed with the same diameter, an inner peripheral thread portion 13b is formed near the primary side opening 13a of the primary side passage 13, and an inner peripheral thread portion 15b is formed near the secondary side opening 15a of the secondary side passage 15. With this configuration, the valve opening / closing speed reduction unit 1 has a linear structure and can be coaxially attached to a drive actuator of a general air-operated valve, so it is easy to arrange in an integrated gas system or the like. However, the primary side passage 13, the valve chamber 14, and the secondary side passage 15 do not necessarily have to be substantially coaxial as long as they are arranged in series.

[0025] The seal part 20 is a member provided around the opening 13c of the primary-side passage 13 in the valve chamber 14. The seal part 20 is a member having an annular shape and flexibility, and closes the opening 13c when one end of a check valve body 30 described later abuts against it.

[0026] The check valve body 30 is a member that is movably provided in the valve chamber 14 and opens and closes between the primary-side passage 13 and the secondary-side passage 15 by separating from or abutting against the seal part 20 described later. In this embodiment, the check valve body 30 forms a substantially bottomed and substantially cylindrical shape with one end 30a closed, and is provided coaxially with the valve chamber 14 in the valve chamber 14 such that one end 30a faces the seal part 20 side. The outer periphery of the other end 30b side of the check valve body 30 is configured to fit and slide with the inner periphery of the valve chamber 14. For this reason, in order to secure a fluid flow path, one or a plurality of through holes 30c penetrating from the inner peripheral side to the outer peripheral side are provided in the check valve body 30. With this configuration, a fluid flow path is formed that leads from the space in the valve chamber 14, through the through holes 30c and the inner peripheral side of the check valve body 30, and out to the secondary-side passage 15. Note that the portion composed of the check valve body 10, the seal part 20, and the check valve body 30 is also referred to as a check valve mechanism (1).

[0027] The coil spring (biasing means) 40 is a member that biases the check valve body 30 toward the seal part side. With this configuration, when fluid flows from the secondary-side passage 15 to the primary-side passage 13, the check valve mechanism (1) is surely closed.

[0028] Here, the bypass passage 50 penetrates the one end portion 30a of the check valve body 30 in the axial direction of the check valve body 30 and opens inside the annular contact portion with the seal portion 20 at the one end portion 30a. For this reason, the bypass passage 50 communicates the primary side passage 13 and the secondary side passage 15 even in a state where the check valve body 30 is in contact with the seal portion 20 (also referred to as "check valve closed state"). The bypass passage 50 is a small-diameter passage and allows only a small flow rate of fluid to flow through. By selecting the diameter of this bypass passage 50, the flow rate of the fluid flowing through the bypass passage 50 can be adjusted. Note that the direction of the bypass passage 50 is not limited to the axial direction as long as the primary side passage 13 and the secondary side passage 15 can be communicated even in the check valve closed state, and it may be a direction forming an angle with the axial direction.

[0029] Next, the operation of the valve opening / closing speed reduction unit 1 of the present embodiment configured as described above will be described with reference to FIG. 2. When the fluid flows from the primary side passage 13 to the secondary side passage 15, as shown in FIG. 2(a), the check valve body 30 is separated from the seal portion 20 and the check valve mechanism (1) opens, and a large flow rate of fluid flows from the primary side passage 13 through the gap between the check valve body 30 and the seal portion 20 into the valve chamber 14, and further flows through the plurality of through holes 30c and the inside of the check valve body 30 to the secondary side passage 15.

[0030] On the other hand, when the fluid flows from the secondary side passage 15 to the primary side passage 13, as shown in FIG. 2(b), the check valve body 30 comes into contact with the seal portion 20 and the check valve mechanism (1) closes, and only a small flow rate of fluid flows through the bypass passage 50. By providing the valve opening / closing speed reduction unit 1 having this simple structure in the operation air supply line of the air-operated valve, the speed of the closing operation or the opening operation of the valve can be reduced. For this reason, the valve opening / closing speed reduction unit 1 can be realized only by adding slight processing to the check valve structure. Note that a flow rate adjustment mechanism may be provided in this bypass passage 50.

[0031] (Second Embodiment) In this embodiment, in the valve opening / closing speed reduction unit 1 of the first embodiment, instead of the bypass passage 50 provided in the check valve body 30, a bypass passage 51 provided inside the check valve body 10 is adopted. Other configurations of this embodiment are the same as those of the first embodiment. The same components are denoted by the same reference numerals, and detailed descriptions thereof are omitted. FIG. 3 is a longitudinal sectional view showing a valve opening / closing speed reduction unit 2 according to this embodiment. The bypass passage 51 of this embodiment includes, in the inner body 11 of the check valve body 10, a first passage 51a extending from the valve chamber 14 toward the outer peripheral portion, a second passage 51b extending from the primary side passage 13 toward the outer peripheral portion, and a third passage 51c communicating the first passage 51a and the second passage 51b.

[0032] In this embodiment, the first passage 51a and the second passage 51b are formed by drilling through holes penetrating from the outer peripheral surface of the inner body 11 radially inwardly into the valve chamber 14 or the primary side passage 13 with a drill, and sealing the outer peripheral portion sides thereof by fitting sealing members 51d made of, for example, soft stainless steel. The third passage 51c is formed by drilling a blind hole extending in a direction parallel to the axis from the primary side end surface 11b of the inner body 11 and communicating with the first passage 51a and the second passage 51b, and sealing the entrance by fitting a sealing member 51e made of soft stainless steel. The bypass passage 51 composed of the first to third passages 51a to 51c communicates the primary side passage 13 and the secondary side passage 15 even when the check valve body 30 is in contact with the seal portion 20. Only a small flow rate of fluid flows through the small-diameter passages constituting this bypass passage 51. By selecting the diameter of at least one of the first to third passages 51a to 51c constituting this bypass passage 51, the flow rate of the fluid flowing through the bypass passage 51 can be adjusted. In this embodiment, a flow rate adjustment mechanism for adjusting the flow rate of the fluid flowing through the bypass passage 51 is provided by making the shape of the sealing member 51e needle-like and screwing it into the third passage 51c to adjust the insertion amount.

[0033] Next, the operation of the valve opening / closing speed reduction unit 2 of this embodiment configured as described above will be described with reference to FIG. 4. When the fluid flows from the primary side passage 13 to the secondary side passage 15, as shown in FIG. 4(a), the check valve body 30 separates from the seal portion 20 and the check valve mechanism (2) opens, and a large flow rate of fluid flows from the primary side passage 13 through the gap between the check valve body 30 and the seal portion 20 into the valve chamber 14, and further flows through the plurality of through holes 30c and the inside of the check valve body 30 to the secondary side passage 15.

[0034] On the other hand, when the fluid flows from the secondary side passage 15 to the primary side passage 13, as shown in FIG. 4(b), the check valve body 30 abuts against the seal portion 20 and the check valve mechanism (2) closes, and only a small flow rate of fluid flows through the bypass passage 51. By providing the valve opening / closing speed reduction unit 2 having this simple structure in the operation air supply line of the air-operated valve, the speed of the closing operation or the opening operation of the valve can be reduced. Even with this configuration, the valve opening / closing speed reduction unit 2 can be realized by simply adding slight processing to the check valve structure (2).

[0035] (Third Embodiment) In this embodiment, in the valve opening / closing speed reduction unit 1 of the first embodiment, instead of the check valve body 30 movably provided in the valve chamber, a check valve body 330 including a central shaft portion 331 fixed in the valve chamber, an annular thin plate-shaped diaphragm portion 332 extending from the outer peripheral side thereof, and an outer ring portion 333 provided on the further outer peripheral side thereof is adopted. FIG. 5 is a longitudinal sectional view showing the valve opening / closing speed reduction unit 3 according to this embodiment. In FIG. 5, 310 is the check valve body, 320 is the seal portion, 330 is the check valve body, and 350 is the bypass passage.

[0036] The check valve body 310 of this embodiment is composed of an outer body 311 and an inner body 312. The outer body 311 is a cylindrical member with a ceiling, and a primary side passage 313 is provided through the ceiling portion 311a, and it has an inner peripheral screw portion 311b on the inner peripheral side. The inner body 312 has an outer peripheral screw portion 312a that engages with the inner peripheral screw portion 311b on the outer peripheral side, and has a secondary side passage 315 inside. A valve chamber 314 is formed between the ceiling portion 311a and the inner body 312 inside the outer body 311. Since the upper part of the secondary side passage 315 is blocked by fitting the central axis portion 331 of the check valve body 330 described later, a through hole 316 is provided to communicate the outer peripheral side of the inner body 312 and the lower part of the secondary side passage 315, thereby communicating the valve chamber 314 and the lower part of the secondary side passage 315. An O-ring 317 is provided below the through hole 316 on the outer peripheral side of the inner body 312 to ensure the airtightness of the valve chamber 314. Similar to the valve opening / closing speed reduction unit 1 of the first embodiment, an inner peripheral screw portion 313b is formed near the primary side opening 313a of the primary side passage 313, and an inner peripheral screw portion 315b is formed near the secondary side opening 315a of the secondary side passage 315.

[0037] The seal portion 320 is a portion around the opening 313c of the primary side passage 313 in the valve chamber 314, and is the lower surface of the ceiling portion 311a of the outer body 311. That is, different from the first embodiment, the seal portion 320 is not an independent member but a part of the check valve body 310. When the outer ring portion 333 of the check valve body 330 abuts against the seal portion 320, the flow of a large amount of fluid between the primary side passage 313 and the secondary side passage 315 is blocked.

[0038] The check valve body 330 is a member composed of a central axis portion 331, an annular thin plate-shaped diaphragm portion 332 extending from the outer peripheral side thereof, and an outer ring portion 333 provided on the further outer peripheral side thereof. In the present embodiment, the check valve body 330 is integrally processed as a whole, but it may be formed by integrating after processing as two or more members by welding or the like. The central axis portion 331 is fitted into the upper part of the secondary side passage 315 in the valve chamber 314 and is fixed coaxially with the valve chamber 314. The check valve body 330 is configured such that due to the elastic deformation of the diaphragm portion 332, the outer ring portion 333 is separated from or abuts against the seal portion 320 to open and close between the primary side passage 313 and the secondary side passage 315. Note that the portion composed of the check valve body 310, the seal portion 320, and the check valve body 330 is also referred to as a check valve mechanism (3).

[0039] The bypass flow path 350 in the present embodiment is a groove (350) provided in the seal portion 320. This groove (350) is radially formed in the seal portion 320 so as to cross the outer ring portion 333 in a top view (not shown). The number of this groove (350) may be one or a plurality. Instead of providing the groove (350) in the seal portion 320, it may be provided on the contact surface of the outer ring portion 333 with the seal portion 320, or on both the outer ring portion 333 and the seal portion 320. With these configurations, even when the outer ring portion 333 of the check valve body 330 abuts against the seal portion 320 and the check valve mechanism (3) is closed, the groove (350) communicates the primary side passage 313 and the secondary side passage 315 and allows a small flow rate to flow through.

[0040] Next, the operation of the valve opening / closing speed reduction unit 3 of the present embodiment configured as described above will be described with reference to FIG. 6. When the fluid flows from the primary side passage 313 to the secondary side passage 315, as shown in FIG. 6(a), due to the pressure of the fluid from the primary side, the periphery of the diaphragm portion 332 of the check valve body 330 is deformed so as to move downward, and the outer ring portion 333 is separated from the seal portion 320 (the check valve mechanism (3) opens). As a result, a large flow rate of fluid flows from the primary side passage 313 through the gap between the outer ring portion 333 and the seal portion 320 into the valve chamber 314, and further flows through the through hole 316 into the secondary side passage 315.

[0041] On the other hand, when the fluid flows from the secondary-side passage 315 to the primary-side passage 313, as shown in FIG. 6(b), due to the pressure of the fluid from the secondary side, the periphery of the diaphragm portion 332 of the check valve body 330 deforms upward so that the outer ring portion 333 abuts against the seal portion 320 (the check valve mechanism (3) closes). As a result, only a small flow rate of fluid flows through the bypass flow path (groove) 350. Even with this configuration, the valve opening / closing speed reduction unit 3 can be realized by simply adding slight machining to the check valve structure (3). According to the configuration of the present embodiment, even when the differential pressure between the primary side and the secondary side is small, the check valve function acts stably, and stable sealing performance can be obtained.

[0042] (Fourth Embodiment) This embodiment provides a valve device to which the valve opening / closing speed reduction unit 1 of the first embodiment is connected. FIG. 7 shows the valve device 100 of this embodiment. The valve device 100 of this embodiment includes a valve body 110, a valve seat 120, a diaphragm 130 as a valve body, a stem 140, a bonnet 150, an air cylinder actuator 160, and the valve opening / closing speed reduction unit 1. Note that the part of the valve device 100 other than the valve opening / closing speed reduction unit 1 is also referred to as the "valve device main body (100)".

[0043] The valve body 110 is formed of stainless steel. From the upper surface 110a, a valve chamber 113 having a diaphragm support portion 114 is opened, and an inner peripheral screw portion 115 that is screwed with the bonnet 150 is formed. Also, inside the valve body 110, a first flow path 111 and a second flow path 112 that communicate with the valve chamber 113 are formed.

[0044] The valve seat 120 is an annular member fitted into an annular groove provided around the opening of the first flow path 111 at the bottom surface of the valve chamber 113, and is formed of fluororesin (PCTFE).

[0045] The diaphragm 130 is a valve body. As shown in FIG. 7, it is disposed on the diaphragm support portion 114 of the valve body 110, separated from or in contact with the valve seat 120, and is a member that communicates or blocks between the first flow path 111 and the second flow path 112. The diaphragm 130 is formed by bulging upward the central portion of a laminated thin metal plate such as special stainless steel and a nickel-cobalt alloy thin plate, and has a spherical shell shape convex upward in its natural state. The diaphragm 130 is supported by the diaphragm support portion 114 of the valve body 110 and is fixed by being pressed by the annular end face of the lower end portion 150d of the bonnet 150 via a ring-shaped presser adapter 135. The diaphragm 130 defines a part of the flow path, is pressed by a diaphragm presser 145 described later and elastically deformed, and when it comes into contact with the valve seat 120, the flow path is closed, and when it is separated from the valve seat 120, the flow path is opened.

[0046] The stem 140 is a substantially stepped cylindrical member that connects a diaphragm presser 145 for pressing the diaphragm and an air cylinder actuator 160, and is provided inside the bonnet 150 so as to be slidable in the vertical direction. A threaded hole 140a is provided on the upper end portion of the stem 140 on the axis, and the outer peripheral threaded portion at the lower end of the operation shaft 164d of the lower piston 164 described later is screwed and connected. On the other hand, a cylindrical recess is provided axially at the lower end portion of the stem 140, and a diaphragm presser 145 made of fluororesin (PCTFE) is fitted therein. The diaphragm 130 can be pressed by the diaphragm presser 145.

[0047] The bonnet 150 is a substantially cylindrical bag-shaped member with an open lower end side. An outer peripheral threaded portion 150c is formed at the lower end portion, and it is screwed with the inner peripheral threaded portion 115 of the valve body 110. Thereby, the bonnet 150 is fixed to the valve body 110, and presses and fixes the diaphragm 130 to the valve body 110 via the presser adapter 135. Inside the bonnet 150, the stem 140 is provided so as to be slidable in the vertical direction, and a coil spring 155 is disposed to bias the stem 140 downward.

[0048] The air cylinder actuator 160 is an actuator that moves the diaphragm 130 between an open position and a closed position, and includes a casing (161, 162), an upper piston 163, and a lower piston 164.

[0049] The casing (161, 162) is a cylindrical container whose interior is partitioned by a partition plate 165 into an upper cylinder chamber 166 and a lower cylinder chamber 167. In the present embodiment, the casing is formed by screwing together an upper casing 161 and a lower casing 162. The lower casing 162 is integrally formed with a cylindrical portion 162b, a lower end plate 162a, and a lower protruding pipe portion 162c. An outer peripheral thread portion 162d provided on the lower protruding pipe portion 162c is screwed into a through-thread hole 150b formed in the upper end plate portion 150a of the bonnet 150 and is fixed by a fixing nut 158. Note that the lower end portion of the lower protruding pipe portion 162c serves as an upper limit stopper for the movable range of the stem 140, and the vertical position can be adjusted by screwing adjustment into the through-thread hole 150b of the bonnet 150. Thereby, the maximum separation amount of the valve seat 120 of the diaphragm 130 driven by the diaphragm presser 145 via the stem 140, that is, the maximum opening degree (Cv value) of the valve device 100 can be adjusted.

[0050] The upper casing 161 is integrally formed with a cylindrical portion 161b and an upper end portion 161a. An inner peripheral thread portion 161c formed at the lower end portion of the cylindrical portion 161b is screwed into an outer peripheral thread portion 162e formed on the cylindrical portion 162b of the lower casing 162. At that time, the outer edge portion of the partition plate (bulkhead) 165 is sandwiched and fixed between the upper end portion of the lower casing 162 and the inner peripheral stepped portion of the cylindrical portion 161b of the upper casing 161, partitioning the interior of the casing (161, 162) into the upper cylinder chamber 166 and the lower cylinder chamber 167. Note that an operation air introduction hole 170 penetrating the upper end portion 161a of the upper casing 161 is provided, and ventilation holes 171 to the non-pressure chamber portion of the upper cylinder chamber 166 and ventilation holes 172 to the non-pressure chamber portion of the lower cylinder chamber 167 are provided in the cylindrical portion 161b.

[0051] The upper piston 163 is disposed in the upper cylinder chamber 166 and is a member driven upward by the pressure of the operation air in the upper pressure chamber 166a formed between the upper piston and the partition plate 165. On the other hand, the lower piston 164 is disposed in the lower cylinder chamber 167 and is a member driven upward by the pressure of the operation air in the lower pressure chamber 167a formed between the lower piston and the lower end plate 162a. The upper piston 163 and the lower piston 164 are coupled by screwing the outer peripheral screw portion at the tip of the connecting shaft 164a that protrudes upward through the partition plate 165 from the lower piston 164 into the screw hole 163d of the upper piston 163. The upper piston 163 and the lower piston 164 are integrally biased downward by a coil spring 155 disposed in the bonnet 150 and are configured to slide upward under the pressure of the upper pressure chamber 166a and the lower pressure chamber 167a. Note that O-rings 180 are provided on the outer peripheral portions of the upper piston 163 and the lower piston 164, etc., so that they can slide while maintaining airtightness with the inner periphery of the casing (161, 162), etc.

[0052] On the other hand, the lower piston 164 has an operation shaft 164d that protrudes downward. This operation shaft 164d passes through the central hole of the lower end plate 162a of the lower casing 162 and the inside of the lower protruding pipe portion 162c and protrudes, and the outer peripheral screw portion formed at the tip is screwed into the upper screw hole of the stem 140 as described above. Thereby, the operation shaft 164d is coupled to the stem 140, and the displacement of the diaphragm 130 can be operated via the diaphragm presser 145 attached to the lower end portion thereof.

[0053] The upper piston 163 has an upper operation air passage 163b inside that introduces operation air from the operation air introduction hole 170 of the upper casing 161 to supply the operation air to the upper pressure chamber 166a and the lower piston 164. Further, the lower piston 164 also has a lower operation air passage 164b inside that introduces the operation air from the upper operation air passage 163b at the connection portion with the upper piston 163 and supplies the operation air to the lower pressure chamber 167a.

[0054] Here, the secondary side passage 15 side of the valve opening / closing speed reduction unit 1 of the first embodiment is connected to the operation air introduction hole 170 of the air cylinder actuator 160. Specifically, a joint 190 having an outer peripheral thread portion on both sides is used, one end portion thereof is screwed into the inner peripheral thread portion of the operation air introduction hole 170, and the other end portion is screwed into the inner peripheral thread portion 15b of the secondary side passage 15 of the valve opening / closing speed reduction unit 1, thereby connecting the two. An external control solenoid valve (not shown) is attached to the primary side passage 13 of the valve opening / closing speed reduction unit 1 via an operation air supply line (not shown) so as to switch between operation air supply (ON) and atmospheric pressure release (OFF).

[0055] Next, the operation of the valve device 100 of the present embodiment configured as described above will be described. First, when operation air is not supplied to the valve device 100, the combined body of the upper piston 163, the lower piston 164, the stem 140, and the diaphragm presser 145 receives the biasing force of the coil spring 155 and presses the diaphragm 130 against the valve seat 120, and the valve is in a fully closed state.

[0056] When the control solenoid valve (not shown) is turned ON, operation air is introduced from an operation air supply source (not shown) into the air cylinder actuator 160 via an operation air supply line (not shown) and the valve opening / closing speed reduction unit 1, and is supplied from the upper operation air passage 163b to the upper pressure chamber 166a and from the lower operation air passage 164b to the lower pressure chamber 167a. As a result, the pressures in the upper pressure chamber 166a and the lower pressure chamber 167a increase, and the combined body of the upper piston 163, the lower piston 164, the stem 140, and the diaphragm retainer 145 rises against the biasing force of the coil spring 155, and the upper end of the stem 140 abuts against and stops at the lower end of the lower protruding pipe portion 162c of the lower casing 162. Thereby, the diaphragm 130 is separated from the valve seat 120 and the valve is fully opened.

[0057] In this valve opening operation, in the valve opening / closing speed reduction unit 1, since the operating air flows from the primary side to the secondary side, as shown in Fig. 2(a), the check valve body 30 is separated from the seal portion 20 and the check valve mechanism (1) opens, and a large flow rate of fluid flows from the primary side passage 13 through the gap between the check valve body 30 and the seal portion 20 into the valve chamber 14, and further flows through the plurality of through holes 30c and the inside of the check valve body 30 to the secondary side passage 15. Therefore, since the operating air is supplied to the valve body (100) at a large flow rate, the above valve opening operation is performed quickly.

[0058] Next, referring to Fig. 7, in the valve device 100 in the fully open state, when the control solenoid valve (not shown) is turned OFF, the operating air supply line (not shown) is opened to the atmosphere, and the operating air passes from the lower pressure chamber 167a and the upper pressure chamber 166a through the lower operating air passage 164b and the upper operating air passage 163b, and is further exhausted through the valve opening / closing speed reduction unit 1. As a result, the pressures in the upper pressure chamber 166a and the lower pressure chamber 167a decrease, and the combined body of the upper piston 163, the lower piston 164, the stem 140, and the diaphragm retainer 145 descends under the biasing force of the coil spring 155. Thereby, the diaphragm 130 is brought into contact with the valve seat 120 to close the valve.

[0059] In this valve closing operation, in the valve opening / closing speed reduction unit 1, as shown in Fig. 2(b), the check valve body 30 abuts against the seal portion 20 and the check valve mechanism (1) closes, and only a small flow rate of fluid flows through the bypass flow path 50. Therefore, since the exhaust of the operating air from the valve body (100) is performed at a low flow rate, the above valve closing operation is performed at a low speed.

[0060] (Fifth Embodiment) This embodiment provides a valve device 101 in which the valve opening / closing speed reduction unit 1 of the first embodiment is connected in the reverse direction to that of the fourth embodiment. Other configurations of this embodiment are the same as those of the third embodiment, and the same components are denoted by the same reference numerals, and detailed descriptions thereof are omitted. FIG. 8 is a longitudinal sectional view showing the valve device 101 of this embodiment. In this embodiment, the primary side passage 13 side of the valve opening / closing speed reduction unit 1 of the first embodiment is connected to the operating air introduction hole 170 of the air cylinder actuator 160. Specifically, a joint 190 having external thread portions on both sides is used, one end portion thereof is screwed into the internal thread portion of the operating air introduction hole 170, and the other end portion is screwed into the internal thread portion 13b of the primary side passage 13 of the valve opening / closing speed reduction unit 1, thereby connecting the two. An external control electromagnetic valve (not shown) is connected to the secondary side passage 15 of the valve opening / closing speed reduction unit 1 via an operating air supply line (not shown) so as to switch between operating air supply (ON) and atmospheric pressure release (OFF).

[0061] Next, the operation of the valve device 101 of this embodiment configured as described above will be described. The operation of the valve device main body (101) is the same as that of the fourth embodiment except for the valve opening / closing operation speed.

[0062] That is, when the control electromagnetic valve (not shown) is turned ON, the operating air is introduced from the operating air supply source (not shown) into the air cylinder actuator 160 via the operating air supply line (not shown) and the valve opening / closing speed reduction unit 1, and the valve device 101 is fully opened.

[0063] In this valve opening operation, in the valve opening / closing speed reduction unit 1, since the operating air flows from the secondary side to the primary side, as shown in FIG. 2(b), the check valve body 30 abuts against the seal portion 20 and the check valve mechanism (1) closes, and only a small flow rate of fluid flows through the bypass passage 50. Therefore, since the supply of the operating air from the valve body (100) is made at a small flow rate, the above valve opening operation is performed at a low speed.

[0064] Next, referring to FIG. 7, in the valve device 101 in the fully open state, when the control solenoid valve (not shown) is turned OFF, the operating air supply line (not shown) is opened to the atmosphere, and the operating air passes from the lower pressure chamber 167a and the upper pressure chamber 166a through the lower operating air passage 164b and the upper operating air passage 163b, and is further exhausted through the valve opening / closing speed reduction unit 1. Thereby, the valve device 101 is closed.

[0065] In this valve closing operation, in the valve opening / closing speed reduction unit 1, since the operating air flows from the primary side to the secondary side, as shown in FIG. 2(a), the check valve body 30 is separated from the seal portion 20 and the check valve mechanism (1) opens, and a large flow rate of fluid flows from the primary side passage 13 through the gap between the check valve body 30 and the seal portion 20 into the valve chamber 14, and further flows through the plurality of through holes 30c and the inside of the check valve body 30 to the secondary side passage 15. Therefore, since the operating air is exhausted from the valve body (100) at a large flow rate, the above valve closing operation is performed quickly.

[0066] (Application Example) FIG. 9 is a schematic cross-sectional view showing a vaporizer system 200 using the valve device 100 of the fourth embodiment shown in FIG. 7 as a secondary side valve. In FIG. 9, 210 is a liquid introduction joint, 220 is an on-off valve, 230 is a vaporization chamber, 240 is a pressure sensor, 250 is an on-off valve (primary side on-off valve), 260 is a flow control valve, 270 is a pressure sensor, 100 is a valve device of the third embodiment (secondary side on-off valve), and 280 is a gas delivery joint. In this vaporizer system 200, the liquid introduced from the liquid introduction joint 210 is heated and vaporized in the vaporization chamber 230, and the vaporized gas is flow-controlled by a pressure-type flow control device including a pressure sensor 240, an on-off valve 250, a flow control valve 260, and a pressure sensor 270, and is sent out from the gas delivery joint 280 through the valve device 100. Here, the on-off valves 220, 250, and 100 are air-operated valves controlled by operation air controlled by solenoid valves, respectively.

[0067] When the power is turned off after using such a vaporizer system 200, the supply of operation air to the on-off valve 250 (primary-side on-off valve) and the valve device 100 (secondary-side on-off valve) is stopped simultaneously because the respective solenoid valves are turned off at the same time. When a conventional on-off valve is used as the secondary-side valve, the on-off valve 250 (primary-side valve) and the secondary-side valve (100) are closed simultaneously with the simultaneous stop of the operation air, and high-pressure gas is trapped in the flow path 290 between the valves, and there is a problem that the trapped process gas leaks out from the flow control valve 260 or the like.

[0068] On the other hand, when the valve device 100 is adopted as the secondary-side valve, after the on-off valve 250 (primary-side valve) is closed, the valve device 100 (secondary-side valve) is closed with a delay, so that the gas can be discharged from the gas delivery joint 280 during that time. Therefore, the problem of the trapped process gas leaking out can be reduced.

[0069] FIG. 10 is a pressure change graph showing the effect of the valve device 100 in the vaporizer system 200, and shows the pressure change in the flow path 290 between the valves when the respective solenoid valves of the on-off valve 250 (primary-side valve) and the valve device 100 (secondary-side valve) shown in FIG. 9 are opened and closed simultaneously. When the solenoid valve opens, the on-off valve 250 (primary-side valve) and the valve device 100 (secondary-side valve) open simultaneously and rapidly accordingly, so that gas is supplied to the flow path 290 between the valves from the primary side, and the pressure rapidly rises to 0.2 MPa. On the one hand, when the solenoid valve closes, the on-off valve 250 (primary side valve) closes rapidly, while the valve device 100 (secondary side valve) closes slowly. Therefore, within about 4 seconds from when the on-off valve 250 closes until the valve device 100 is completely closed, gas is discharged from the flow path 290 between the valves, and the pressure sufficiently decreases to 0.04 MPa.

[0070] As described above, the embodiments of the present invention have been described in detail. However, the present invention is not limited to such specific examples, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims.

[0071] For example, in the above-described first and second embodiments, a check valve body 30 movably provided in the valve chamber 14 is adopted. Among them, in the first embodiment, a bypass flow path 50 is provided in the check valve body 30, and in the second embodiment, an internal bypass flow path 51 is provided in the check valve body 10. On the other hand, in the third embodiment, a check valve body 330 deformably provided in the valve chamber 314 is adopted, and a groove (350) is provided in the seal portion 320 as the bypass flow path 350. However, while adopting the deformable check valve body 330 of the third embodiment, the bypass flow path 350 may be provided inside the valve body 330 or inside the outer body 311 as in the first and second embodiments.

[0072] Also, in the above-described fourth and fifth embodiments, the valve opening / closing speed reduction unit 1 of the first embodiment is connected to the valve device main body (100 or 101), but the valve opening / closing speed reduction unit 2 of the second embodiment or the valve opening / closing speed reduction unit 3 of the third embodiment may be connected to the valve device main body (100 or 101).

[0073] Also, in the above-described fourth and fifth embodiments, a normally closed type valve is used as the valve device main body (100 or 101), but a normally open type valve device may be used. In that case, in the fourth embodiment, the speed of the valve opening operation is reduced, and in the fifth embodiment, the speed of the valve closing operation is reduced.

[0074] In the fourth and fifth embodiments described above, an air cylinder actuator 160 of a two-stage cylinder type is used. However, a single-stage cylinder type may be used, or an air cylinder actuator 160 of a multi-stage cylinder type other than two-stage may be used.

[0075] In each of the above embodiments, the check valve bodies 10 and 310 and the check valve discs 30 and 330 having a predetermined shape are used. However, the check valve bodies 10 and 310 may have any shape as long as they have a primary passage 13 or 313, a valve chamber 14 or 314, and a secondary passage 15 or 315 connected in series inside. The check valve discs 30 and 330 may have any shape as long as they are provided movably or deformably in the valve chamber 14 or 314 and open and close between the primary passage 13 or 313 and the secondary passage 15 or 315 by separating from or contacting the seal portion 20 or 320.

[0076] In the fourth and fifth embodiments and the application examples described above, the valve device main body (100 or 101) and the valve opening / closing speed reduction unit 1 are connected by a joint 190. However, the two may be connected by a pipe such as an air tube.

[0077] In each of the above embodiments, the bypass passage 50 is formed by a single straight hole (50), the bypass passage 51 is formed by connecting a plurality of holes (the first to third passages 51a to 51c) in series, and the bypass passage 350 is formed by a groove. However, the present invention is not limited to these. For example, it may be formed by a plurality of holes provided in parallel, or formed by combining series holes and parallel holes.

Explanation of Reference Numerals

[0078] 1, 2, 3 Valve opening / closing speed reduction unit 10 Check valve body 11 Inner body 11a Outer peripheral threaded portion 11b Primary side end face 12 Outer body 12a Inner peripheral threaded portion 13 Primary side passage 13a Primary side opening 13b Inner circumferential thread portion 13c Opening 14 Valve chamber 15 Secondary-side passage 15a Secondary-side opening 15b Inner circumferential thread portion 20 Seal portion 30 Check valve body 30a One end portion 30b The other end portion 30c Through hole 40 Coil spring 50, 51 Bypass flow path 51a First passage 51b Second passage 51c Third passage 51d, 51e Sealing member 100, 101 Valve device 110 Valve body 110a Upper surface 111 First flow path 112 Second flow path 113 Valve chamber 114 Diaphragm support portion 115 Inner circumferential thread portion 120 Valve seat 130 Diaphragm 135 Pressing adapter 140 Stem 140a Threaded hole 145 Diaphragm presser 150 Bonnet 150a Upper end plate portion 150b Through threaded hole 150c Outer circumferential thread portion 150d Lower end portion 155 Coil spring 158 Fixed nut 160 Air cylinder actuator 161 Upper casing 161a Upper end portion 161b Cylindrical portion 161c Inner circumferential thread portion 162 Lower casing 162a Lower end plate 162b Cylindrical part 162c Lower protruding pipe part 162d Outer peripheral thread part 162e Outer peripheral thread part 163 Upper piston 163b Upper operating air passage 163d Threaded hole 164 Lower piston 164a Connecting shaft 164b Lower operating air passage 164d Operating shaft 165 Partition plate 166 Upper cylinder chamber 166a Upper pressure chamber 167 Lower cylinder chamber 167a Lower pressure chamber 170 Operating air inlet hole 171 Vent hole 172 Vent hole 180 O-ring 190 Joint 200 Vaporizer system 210 Liquid inlet joint 220 On-off valve 230 Vaporization chamber 240 Pressure sensor 250 On-off valve (primary side on-off valve) 260 Flow control valve 270 Pressure sensor 280 Gas delivery joint 290 Flow path between valves 310 Check valve body 311 Outer body 311a Ceiling part 311b Inner peripheral thread part 312 Inner body 312a Outer peripheral thread part 313 Primary side passage 313a Primary side opening 313b Inner peripheral thread part 313c Opening 314 Valve chamber 315 Secondary side passage 315a Secondary side opening Internal thread portion of 315b Through-hole 316 O-ring 317 Sealing portion 320 Check valve body 330 Central axis portion 331 Diaphragm portion 332 Outer ring portion 333 Bypass flow path 350

Claims

1. A unit for controlling operating air for an air operated valve, the unit comprising: a check valve body having a primary side passage, a valve chamber, and a secondary side passage connected in series therein; a seal portion provided around an opening of the primary side passage in the valve chamber; and a check valve element provided movably or deformably within the valve chamber, and moving away from or coming into contact with the seal portion to open and close between the primary side passage and the secondary side passage, a bypass flow passage in the check valve element or the check valve body that connects the primary side passage and the secondary side passage and allows a small flow rate to flow even when the check valve element is in contact with the seal portion.

2. 2. The valve opening / closing speed reduction unit according to claim 1, wherein the primary side passage, the valve chamber, and the secondary side passage are coaxially arranged within the check valve body, each having a circular cross section, and a diameter of the valve chamber is larger than diameters of the primary side passage and the secondary side passage.

3. the check valve element has a cylindrical shape with one end closed and a bottom, and is provided in the valve chamber coaxially with the valve chamber and movable in an axial direction of the check valve element with the one end facing the seal portion, The valve opening / closing speed reduction unit according to claim 2 , wherein the bypass passage is provided so as to penetrate the one end of the check valve in an axial direction.

4. 3. The valve opening / closing speed reduction unit according to claim 2, wherein the bypass flow path includes, within the check valve body, a first passage extending from the valve chamber toward an outer periphery, a second passage extending from the primary side passage toward an outer periphery, and a third passage connecting the first passage and the second passage.

5. The valve opening / closing speed reduction unit according to claim 1 , wherein a flow rate adjustment mechanism is provided in the bypass flow passage.

6. 3. The valve opening / closing speed reduction unit according to claim 2, wherein the check valve body comprises: an inner body having the primary side passage and the valve chamber therein, and an outer circumferential threaded portion on an outer circumferential side; and a bottomed cylindrical outer body having an inner circumferential threaded portion on an inner circumferential side that screws into the outer circumferential threaded portion, and having the secondary side passage passing through a bottom of the outer circumferential side.

7. 2. The valve device according to claim 1, further comprising a biasing means for biasing the check valve body toward the seal portion.

8. The valve device according to claim 3 , wherein the check valve body is provided with one or a plurality of through holes extending from an inner periphery side to an outer periphery side.

9. the check valve element comprises a central shaft portion fixed coaxially within the valve chamber, a circular thin plate-like diaphragm portion extending from an outer periphery of the central shaft portion, and an outer ring portion provided on the outer periphery of the diaphragm portion, the outer ring portion is moved away from or brought into contact with the seal portion by elastic deformation of the diaphragm portion, thereby opening and closing the space between the primary passage and the secondary passage, The bypass flow path is a groove provided in at least one of the seal portion and a contact surface of the outer ring portion with the seal portion. The valve opening / closing speed reduction unit according to claim 2 .

10. 10. The valve opening / closing speed reduction unit according to claim 9, wherein the check valve body comprises: a top-opening cylindrical outer body having an inner circumferential thread portion on its inner circumferential side, the primary side passage penetrating a ceiling portion thereof; and an inner body having an outer circumferential thread portion on its outer circumferential side which screws into the inner circumferential thread portion and has the secondary side passage therein; the valve chamber is formed between the ceiling portion inside the outer body and the inner body; and the central axis portion of the check valve element is fixed to the inner body.

11. 11. A valve device comprising: a valve device main body including a valve body, a valve element, and an air cylinder actuator that moves the valve element; and a valve opening / closing speed reduction unit according to any one of claims 1 to 10, connected to an operation air inlet hole of the air cylinder actuator.

12. The valve device according to claim 11 , wherein a secondary passage side of the valve opening / closing speed reduction unit is connected to an operating air inlet of the air cylinder actuator.

13. The valve device according to claim 11 , wherein a primary passage side of the valve opening / closing speed reduction unit is connected to an operating air introduction hole of the air cylinder actuator.

Images