Abstract: The present invention relates to a U Motion gate valve that maintains a tight seal on the outlet side when closing the valve through U Motion operation in the state that the tip and end of the main shaft are free ends using the principle of the class 3 lever.

Abstract: A screw compressor comprises two screw rotors arranged in a screw rotor chamber, and mounted on the compressor housing to be rotatable about respective screw rotor axes, and mesh with one another. At least one control slide is arranged in a slide channel of the compressor housing, adjacently to both screw rotors by means of slide compression wall surfaces, is movable in a displacement direction parallel to the screw rotor axes, is rigidly connected to a piston rod that leads to a cylinder assembly for moving the at least one control slide, and is guided relative to the compressor housing by means of a guide insert that movably receives the piston rod in the displacement direction. The piston rod is guided transversely to the displacement direction in the guide insert in elastically resilient fashion by means of a guide element.

Abstract: An actuator includes a piston and a housing. The piston includes a piston shaft that is configured to reciprocate within a chamber of the housing. The actuator includes a gland electrically coupled to the housing. The gland forms at least a portion of a first end of the chamber. The actuator also includes a first conductor positioned in the chamber. The first conductor is coupled to the gland and to a first side of the piston to electrically couple the piston to the housing.

Abstract: A metal diaphragm valve includes a body with a valve seat provided to a valve chamber communicating a primary flow path and a secondary flow path, a metal diaphragm having a center portion disposed above the valve chamber, the center portion vertically moving to make contact with the valve seat, and a stem provided above the metal diaphragm so as to be able to freely ascend and descend to cause the center portion of the metal diaphragm to move downward. A flow-path restriction part is provided to a part of the secondary flow path. The metal diaphragm valve is quite suitable as a valve for ALD process, the valve favorably reduces fluctuations of a Cv value due to deformation of a resin-made valve seat with time even after the valve is opened and closed at a level of ten million times while a fluid at high temperatures is flowing.

Abstract: A double action directional fluid flow valve includes a stepped piston connected with a poppet valve and moveable by a controller between open and closed positions by applying a continuous pressure to a small diameter piston face and selectively applying and removing pressure from a large diameter piston face to move the poppet valve between an open position and a closed position.

Abstract: A control valve including: a valve body, a flow shutter operatively interposed between an inlet and an outlet, a driving spindle having at least a first actuating end and a second end connected to the flow shutter. The valve also includes a differential pressure automatic regulation device, comprising: a cup-shaped body arranged around the driving spindle and axially mobile with respect to said driving spindle; a spring operatively interposed between the valve body and the cup-shaped body to push the latter away from the flow shutter; a rolling membrane having a radially inner edge fixed to the cup-shaped body and a radially outer edge fixed to the valve body to delimit a first chamber in fluid communication with the inlet and a second chamber in fluid communication with the outlet.

Abstract: A blowout preventer (BOP) includes a pressure driven operator that is equipped with a balancing circuit to offset pressure inside the BOP. The operator, which is used to drive a ram, includes a piston, coupled to the ram by an operator arm, and a balance arm on a side of the piston opposite the operator arm. Pressure from inside the BOP communicates to an end of the balance arm opposite the piston and exerts a force to drive the ram radially inward.

Abstract: A valve assembly arrangement for an injection valve may have a central longitudinal axis, a valve assembly of the inward opening type, and a valve assembly of the outward opening type, wherein the valve assembly of the outward opening type is axially arranged adjacent and fixedly coupled to the valve assembly of the inward opening type such that the valve assembly of the inward opening type is operable to inject fluid into the valve assembly of the outward opening type for increasing a fluid pressure in the valve assembly of the outward opening type to open the valve assembly of the outward opening type to enable dispensing of the fluid from the valve assembly arrangement.

Abstract: A fluid control valve includes: a resin valve main body including inlet and outlet ports in opposite side surfaces, a valve chamber communicating between the inlet and outlet ports and opening at the upper surface center of the main body, and a valve seat provided in an inner wall of the chamber; a valve element movable into or out of contact with the valve seat; and a valve upper body including a drive part to drive the valve element. An inflow passage is formed like an L shape extending through the inner wall to communicate between the inlet port and the chamber via the valve seat. The inner wall is cylindrical having a thick-wall portion to have a wall thickness thicker on the inlet port side than on the outlet port side. The valve main body is provided, at a center of a lower surface, with a resin injected part.

Abstract: Valve control device includes a body with a longitudinal axis, a control member housed at least partially in the body in a bottom portion along the longitudinal axis, a piston movable along the longitudinal axis and housed in a portion of the body forming with the piston a control chamber of the piston, an element movable in rotation with respect to the longitudinal axis on a top portion of the body, and sealing means between the movable element and the control chamber in the area of the connection port and/or of the passage.

Abstract: An actuator for operating a linear valve, such as a gate valve, includes a sealing plate that extends across the diameter of a housing. A diaphragm is located on, and fully supported by, the plate. When pressure media urges the diaphragm and sealing plate downward, the sealing plate urges a step downward to actuate a valve. A hub and an annular support plate can be assembled to form the plate, and the plate can be different sizes by selecting different sized annular support plates.

Abstract: An apparatus for actuating a valve includes a housing having an axis, a valve end, a cap end, and a cylindrical sidewall defining an inner diameter surface of the housing. A cap is connected to the cap end of the housing. An inlet is located in one of the cap and the housing. A plate is positioned within the housing, the plate having an outer diameter that slidingly engages the inner diameter surface of the housing. The plate moves between an extended position and a retracted position in response to pressure media from the inlet. A down stop is in contact with the plate. A seal nut has a first end in engagement with the down stop. The seal nut has a second end with an end surface, the end surface being spaced apart from the cap when the plate is in the extended position.

Abstract: Actuator for a valve, comprising a first piston, a first piston rod and a first fluid chamber for enabling movement of the first piston and the first piston rod. The actuator has a second piston, a second piston rod, the second piston rod being coaxially arranged with the first piston rod and radially enclosing at least a part of the first piston rod. A second fluid chamber is arranged for the second piston, for enabling movement of the second piston and the second piston rod. A first fluid channel is arranged in communication with each of the first and the second fluid chambers, for effecting, when fluid is introduced into the first fluid channel, movement of the first piston and the second piston. Also, a valve comprising such actuator is disclosed.

Abstract: Mounting assemblies for use with fluid control devices are disclosed. An example apparatus includes a bonnet to be coupled to a valve and a mounting assembly including a first side to be coupled to an actuator and a second side to be rotatably coupled at an end of the bonnet to enable a rotational position of the mounting assembly to change relative to the bonnet.

Abstract: An actuator for operating a linear valve, such as a gate valve, includes a swivel coupling for detachably connecting an indicator stem to a plate within the actuator. In embodiments, the coupling includes a body with a lock ring groove. The detachable stem includes a downward facing recess having a groove on an inner diameter surface. The stem is placed on the body, and a lock ring engages both grooves to prevent axial movement of the stem relative to the body. The lock ring does not, however, prevent rotational movement of the stem relative to the body.

Abstract: A hydraulically controlled storage chamber valve includes a closing element that is biased via a first compression spring. The closing element seals a valve seat in a valve body. A tappet protrudes through a bushing in the valve body and is movable by an accumulator piston that is loaded by a second compression spring that is configured to push the closing element out of the valve seat when a specified force ratio is present between spring bias forces and a hydraulically acting force. The tappet is fastened in a region of the bushing such that the tappet is movable in a longitudinal direction and lies flush with a face of the accumulator piston while moving.

Abstract: Exemplary illustrations of a fluid valve, e.g., a return valve for returning residual paint, rinsing agent, and compressed air from a paint line when changing color in a painting system, are disclosed. An exemplary fluid valve may be adjusted between an open position, in which the fluid valve is at least partially open, e.g., for rinsing a paint line with a rinsing agent and for pressurizing the paint line with a new color for the color change, and a closed position, in which the fluid valve is closed, e.g., for applying the new color after the color change. An exemplary fluid valve may switch to the closed position, upon actuation by the medium thereof, e.g., medium flowing through or present in the valve. In another example, a fluid valve may close depending on the fluid present at the input side.

Abstract: A pressure actuated valve is disclosed which includes a plurality of flow openings, and first and second pistons. The first and second pistons are independently actuatable relative to one another, and are releasable coupled to one another by a release sleeve. The pressure actuated valve also includes a closing sleeve that is operatively coupled to the second piston. In an initial position of the second piston, the closing sleeve covers or blocks the plurality of flow openings. The pressure actuated valve includes a ratchet mechanism coupling the release sleeve to the first piston, the ratchet mechanism being adapted to allow movement of the first piston between its initial position and an intermediate position and back to its initial position while allowing the release sleeve to release the second piston after a predetermined number of cycles of movement of the first piston between its initial position and the intermediate position and back to its initial position.

Abstract: A flow rate control device comprises a regulator that adjusts the pressure of a fluid to be supplied, a plurality of narrowed pathways arranged in parallel on the downstream side of the regulator, and an open/close section that switches a predetermined narrowed pathway amongst the plurality of narrowed pathways between an open position and a closed position. One of the pathways can be an open narrowed pathway arranged on the downstream side of the regulator and another can be an opened/closed narrowed pathway arranged downstream of the regulator in parallel with the open narrowed pathway. In this case, the open/close section that switches the opened/closed narrowed pathway between as open position and a closed position.

Abstract: Embodiments of a method of operating a safety valve and a safety valve system are provided. The valve system includes a valve, an actuator, a mechanical override, and an indicator. The actuator includes a fail-safe mechanism and the indicator is configured to indicate whether the fail-safe mechanism is operable during use of at least one of the actuator and the mechanical override. In one embodiment, a method of operating the safety valve includes actuating the valve into an open position and sending a signal to indicate that the fail-safe mechanism is operable to move the valve to the closed position, while the valve is in the open position.

Abstract: Auxiliary valve controlled self-cleaning main valve with mechanical operating means. The valve body (1) of the main valve has an inlet (2) and an outlet (3) interconnected through a flow-through opening, and a movable piston (6) having a main closing element (8) at one of its sides and a brake O-ring (9) at its other side. In the control chamber (5) an auxiliary valve (4) with a control valve stem (7) is provided. Between the piston (6) and the auxiliary valve (4) a compressible spring (12) is positioned. The mechanical operating means is provided with a wedge travel path and adapted to press the control valve stem (7) when force is applied externally and to keep it pressed in without applying external force, further it is adapted to release it when force is applied externally and to keep it released without applying external force.

Abstract: An apparatus for controlling liquid flow wherein the apparatus comprises an orifice and an adjacent flexible diaphragm separated from each other by a gap through which a liquid flows. The diaphragm is sufficiently flexible to vary the gap thereby controlling the rate of liquid flowing through the orifice or to provide a positive liquid shutoff of liquid flowing through the orifice. A method for controlling liquid flow through the apparatus comprises flexing said diaphragm to vary a size of the gap to control the rate of liquid flowing through the orifice or to provide a positive liquid shutoff of liquid from flowing through the orifice.

Abstract: Embodiments of a method of operating a safety valve and a safety valve system are provided. The valve system includes a valve, an actuator, a mechanical override, and an indicator. The actuator includes a fail-safe mechanism and the indicator is configured to indicate whether the fail-safe mechanism is operable during use of at least one of the actuator and the mechanical override. In one embodiment, a method of operating the safety valve includes actuating the valve into an open position and sending a signal to indicate that the fail-safe mechanism is operable to move the valve to the closed position, while the valve is in the open position.

Abstract: An actuator for operating a linear valve, such as a gate valve, includes a sealing plate that extends across the diameter of a housing. A diaphragm is located on, and fully supported by, the plate. When pressure media urges the diaphragm and sealing plate downward, the sealing plate urges a step downward to actuate a valve. A hub and an annular support plate can be assembled to form the plate, and the plate can be different sizes by selecting different sized annular support plates.

Abstract: A valve manifold assembly including a manifold body defining a primary flow passage and a secondary flow passage fluidly coupled therewith through an aperture in the wall of the primary flow passage. A valve including a head portion and a stem extending therefrom is disposed through the aperture. The head portion has a valve sealing surface adjacent and extending around the stem, and a valve seat having a seat sealing surface facing into the primary flow passage extends around the aperture. The valve is selectively shiftable between a closed position wherein the valve sealing surface is sealingly engaged with the seat sealing surface to block fluid flow between the secondary flow passage and the primary flow passage, and an open position wherein the valve sealing surface is spaced apart from the seat sealing surface to enable fluid flow between the secondary flow passage and the primary flow passage.

Abstract: Provided is a valve for vacuum process, including: a first valve body having an inlet port and an outlet port; a sealing unit configured to move forward to and backward from the inlet port so as to have a closed position and an open position; a shaft covered with a bellows, and configured to move the sealing unit between the closed position and the open position; a cover for shielding the bellows from corrosive gas when the sealing unit is in the open position; and a cover guide unit configured to guide the cover to move along the shaft.

Abstract: A hydraulic actuating device for a sliding stem control valve assembly is mounted between a control valve and an actuator housing. The hydraulic actuating device is connected to one of a control valve stem, an actuator stem, and a stem connector and the hydraulic actuating device moves either the control valve stem, the actuator stem, or the stem connector in response to varying hydraulic pressure within the hydraulic actuating device. The hydraulic actuating device may be used to override an actuator of the sliding stem valve during emergency operations, or to provide a backup actuator in the case of a primary actuator malfunction.

Abstract: A diaphragm valve including a valve body, a diaphragm assembly and an actuator assembly having a housing body that isolates the actuator from the ambient atmosphere. The diaphragm assembly is welded to the valve body to reduce and/or eliminate fluid leakage around the diaphragm assembly. Additionally or alternatively, the housing body for the actuator assembly may be welded to the valve body to reduce fluid leakage. The welding may be performed using ultrasonic welding techniques.

Abstract: A sub sea valve actuator system including a piston and cylinder assembly and a return spring arranged in an actuator housing, a hydraulic pump and electric motor assembly associated with the piston and cylinder assembly, and hydraulic flow lines for hydraulic medium driving the piston and cylinder in relative displacement against a force of the return spring. The valve actuator system includes a detector configured to detect an end-of-stroke position of the piston and cylinder assembly. The detector includes at least one of: a motor current monitoring circuit unit, a hydraulic medium pressure sensor unit, a position sensor unit, and a linear variable differential transformer unit. An electromechanical arresting mechanism is arranged to be energized for releasably arresting the return spring in a compressed state in result of the detected end-of-stroke position.

Abstract: The invention relates to a device for connecting a valve housing (2; 2.1; 2.2; 2.3; 2.4) to an actuator (3) in a process valve acting as a lift valve (1; 1.1; 1.2; 1.3; 1.4). The aim of the invention is to design a device for connecting a valve housing to an actuator in a process valve of the type in question that acts as a lift valve, is shorter and less expensive than all known devices of said type, is as safe as possible when opening, and has a very simple design. Said aim is achieved by mounting the lantern-type housing (3.1) on the valve housing (2; 2.1; 2.2; 2.3, 2.4) by means of a bayonet joint (2f, 2g/3.1d, 3.1e) or a bayonet-type joint.

Abstract: An actuator related to the present invention includes a cylinder that has a tubular shape and is filled with a fluid; a piston that divides the inside of the cylinder into a first chamber and a second chamber in an axial direction of the cylinder, is reciprocable inside the cylinder, and opens and closes a main valve; a fluid supplying device for supplying the fluid to the second chamber; biasing device for biasing the piston in the axial direction toward the second chamber; a flow passage that communicates between the first chamber and the second chamber; and a pilot valve that cuts off the flow passage communicating between the first chamber and the second chamber.

Abstract: The present invention is directed to provide an air-operated valve suitable for use in a form using a one-touch joint. A casing 4 is made by an upper casing 22 and a lower casing 21 which are screwed in each other. Piston driving means 12 has a one-touch joint 15 attached to a top part of the upper casing 22.

Abstract: The valve actuator (10) has a movable control element (12) which is typically connected to the valve to be opened/closed and a propulsion device (16) which may be a hydraulically operated piston (16) for moving the movable control element. A resilient element (22) which may be in the form of a spring arrangement has a stroke extending from a first relatively unloaded position to a second relatively loaded position and a transmission mechanism (18) is also provided, where the resilient element is loaded under the action of the propulsion device via the transmission mechanism and is configured to urge the moveable portion of the propulsion device towards the first position via the transmission mechanism when loaded. The transmission mechanism provides a gearing ratio reduction between the moveable portion of the propulsion device and the resilient element.

Abstract: An inlet shut valve or an outlet shut valve has a main diaphragm and a sub-diaphragm, wherein a valve closing pressure chamber and a valve opening pressure chamber are provided, respectively, on the upper surface side and the lower surface side of the main diaphragm. Furthermore, an atmospheric pressure chamber and a pressure chamber constituting a channel are provided, respectively, on the upper surface side and the lower surface side of the sub-diaphragm. A drive shaft constituting a valve element is driven in the direction for bringing about a valve open state by both forces, i.e. a first force acting by pressure difference between the valve closing pressure chamber and the valve opening pressure chamber and a second force acting by pressure difference between the atmospheric pressure chamber and the pressure chamber constituting a channel and acting in the same direction as the first force.

Abstract: A valve actuator includes a valve body, a valve member comprising a shaft, and a piston connected to the shaft, with the valve member being movable by operation of the piston. The valve body comprises a valve chamber that provides fluid communication between an inlet passage and an outlet passage. The shaft is disposed in and extends through a sealed chamber, the sealed chamber being sealed at one end from the valve chamber and at another end from a piston chamber, and a vent that extends from the sealed chamber to an external surface, wherein the shaft extends axially in both directions past sealed ends of the sealed chamber.

Abstract: A pressure control valve is provided, which can variably control the set pressure of a relief valve in accordance with pilot signal pressure that is controlled in an operator's seat and so on when the set pressure of the relief valve required in a replaced working device is changed.

Abstract: An object is to provide a vehicle coolant control valve having excellent response, small size and weight, and low power consumption. A coolant stop valve (vehicle coolant control valve) valve comprises a valve body for controlling the flow of a fluid, the valve body having a magnetic body; a coil spring (urging device) for moving the valve body in the closing direction; a valve seat capable of coming in contact with the valve body; and a solenoid for moving the valve body in the closing direction; wherein the valve body is moved in the opening direction by fluid pressure of a fluid discharged from a water pump (pump) during operation of the water pump (pump), against the movement force of the coil spring (urging device) in the closing direction.

Abstract: A double-seat valve device, with a valve seat region, includes a first circular cylindrical-shaped seat surface with a first diameter, which with a first sealing element forms a radial seal for a connection opening to a first housing part, and a second circular cylindrical-shaped seat surface with a second diameter smaller than the first, which with a second sealing element forms a radial seal for the opening to a second housing part. A third seat surface is arranged between the first and second surfaces. In a closed position of the first closing member, the contact region rests against the third seat surface, to form a solid-state stop for the contact region. A deflecting surface is arranged between the first and third seat surfaces. The deflecting surface has an outlet edge offset to the third seat surface. A direction vector at the outlet edge points away from the second sealing element.

Abstract: A pilot-controlled valve arrangement having at least one valve mechanism mounted in a valve housing for multi-stage switching of a compressed air flow between a feed pressure connection and a working line connection wherein a throttled compressed air flow can be switched in at least one switching stage by a throttle, wherein the pneumatic pilot control has a first control piston mounted in a first control chamber implemented in the valve housing and having a coaxial recess for forming a second control chamber in which a second control piston is mounted, so that an additive control pressure application to the control chambers generates a telescope-like deployment of a ram extending from the second control piston for generating a multi-stage switching stroke for the valve mechanism, in order to implement the throttled compressed air flow in at least one switching stage of the valve mechanism present between the closed and the open valve setting.

Abstract: A valve, particularly a vacuum valve, with at least one closing body to close at least one penetrating opening of the valve and a drive to adjust the closing body between a closed position, in which the closing body closes the penetrating opening, and at least one opened position, in which the closing body at least partially releases the penetrating opening. The drive includes a first volume, which can be impinged with pressure, to adjust the closing body into its closed position and for adjusting it to an opened position, with the valve additionally having an elastic element, which pre-stresses the closing body in a direction of its closed position or its opened position.

Abstract: A proportional control pneumatic cylinder as an air actuator device for a hydraulic pump valve having a valve spool moving in a bore in a valve housing. The device having an actuator housing attachable to the valve housing and having a bore carrying a piston coaxially secured to an end of the valve spool. The device provided with spaced openings in the actuator housing which communicate with the bore therein to introduce air to act on opposite sides of the piston, and factory pretensioned biasing means for normally urging the piston and spool to a center closed position. Surface areas on opposite sides of the piston are approximately equal so that piston movement is approximately proportional to movement of an actuating lever of an air supplying pneumatic control valve over the majority of the range of travel of the actuating lever for both raised and lowered positions.

Abstract: An actuator or valve for use in a well comprising: an obstructing member, such as a piston, moveable between: a first position and a second position; and a retaining member, such as a ball, moveable between: a retaining position which retains the obstructing member in the first position; and, a release position which does not retain the obstructing member in the first position and/or allows or causes the obstructing member to move to the second position; wherein the retaining member is adapted to move in use, from one of the retaining position and release position to the other of the retaining position and release position, at least in part, by centrifugal forces caused by rotation of the actuator/valve. Thus at least some control of the actuation of the actuator/valve may be afforded by rotation thereof. In preferred embodiments some control is also afforded by fluid flow contacting the actuator/valve.

Abstract: A high pressure gas discharge valve for a fire-extinguishing or explosion-preventing system including: a valve body with a gas inlet channel and a gas outlet channel; a valve seat arranged between the channels; and a triggering chamber; a closing piston which is slidably movable within the valve body and has a first end portion forming a pressure surface in the triggering chamber, a second end portion forming a sealing surface, with which it can be sealingly pressed against the valve seat, and a pressure compensation channel via which the triggering chamber communicates with the inlet channel when the closing piston rests on the valve seat; a triggering port in communication with the triggering chamber, for connecting thereto a low pressure triggering device that is capable of generating a pressure drop in the triggering chamber; and a pressure-reducing valve for reducing a pressure of high pressure gas to a reduced pressure suitable for the low pressure triggering device.

Abstract: An isolation valve includes a shield that surrounds and protects the valve closure actuator components from exposure to corrosive fluids that flow through the valve when the valve is open.

Abstract: A valve manifold includes a valve body carrying pairs of laterally spaced piston actuated valves controlled by control modules operative to selectively pressurize and exhaust an outlet port connected to a fluid device and configured in groupings permitting varying valve functionalities.

Abstract: An actuator for a rotary function element, having a housing with at least one pressure means supply and being closed at both sides by a cover, in which housing a piston is guided to reciprocate in a sealing manner, the piston containing diametrically opposed, convolution-like connecting links for a transverse axis of an actuator shaft rotatably mounted in one cover, and having two guide rods Firmly anchored in the housing only at one end and engaging into guides in the piston, with the one guide rod anchored in one cover, whereas the other guide rod is anchored in the other cover, and the two guides end blind in the piston in opposite directions.

Abstract: A valve system comprising a closure member that is linearly translatable within a valve body. A hydraulic override assembly comprises a first end that is connected to the valve body and a first rod member that is connected to the closure member. A linear actuator is connected to a second end of the hydraulic override assembly and comprises a second rod member that is operable to move the first rod member.

Abstract: A reverse flow valve for metering high pressure gaseous media, such as ignition media to the injectors of a scramjet engine in a hyerpsonic flight vehicle, has a metering member that moves parallel to the flow direction of the metered media and throttles the valve in a direction counter to the flow direction. This reduces side loading on the metering member and permits the use of a lighter and smaller actuating mechanism. The metering member can be a pintle having a uniquely configured pintle seat providing bubble tight shut off of the inlet flow without effecting the critical flow contour of the media. The pintle can be driven by a piston that is responsive to push-pull forces of pressurized drive fluid under servo control. The drive fluid is isolated from the gaseous media by a primary seal, which can be seated on the piston without deformation by a seal retainer.

Abstract: To provide a vacuum valve with an improved endurance of a bellows, a vacuum valve comprises: a valve section including a first port, a second port, a valve seat provided between the first and second ports, and a valve element movable into or out of contact with the valve seat; an actuator section including an orifice through which an operating fluid is supplied to the actuator section, and a piston coupled to the valve element, the piston being allowed to operate according to changes of pressure of the operating fluid to apply a driving force to the valve section; and a bellows which can be contracted and elongated as the valve element vertically moves upward and downward. The orifice is designed to have an effective sectional area determined so that an operating speed of the valve element and the piston is controlled to a predetermined speed for preventing damage of the bellows.

Abstract: In a vacuum valve composed of a main valve portion that opens and closes a vale seat in a flow path connecting two ports by a valve member, and an operating portion that performs an opening and closing operation for the valve member, the housing of the main valve portion is assembled by joining the two port members with a cylindrically shaped housing main body formed by a squeezing process for a plate material made of metal, or a ring-shaped material made of the metal. In an end portion of the housing, a flange-shaped attaching portion that is bent inward is formed. The operating portion is attached onto the attaching portion via a ring-shaped supporting seat member. A sealing member is sandwiched between a ring-shaped supporting plate and the attaching portion. Both ends of a bellows are respectively connected to the supporting plate and the valve member.