Abstract: A valve device includes a case having an opened bottom portion and a receiving space formed therein, a base plate covering the open bottom of the case, a flow-in pipe coupled to the base plate to bring in a refrigerant, a boss installed to the base plate and including a plurality of refrigerant flow-in/out holes through which the introduced refrigerant flows in/out, a plurality of flow-in/out pipes coupled to the plurality of refrigerant flow-in/out holes and through which the introduced refrigerant flows in/out, and a pad arranged on the boss and including an open cavity formed therein to selectively opening one of the plurality of refrigerant flow-in/out holes and a connection cavity formed therein to selectively connecting two of the plurality of refrigerant flow-in/out holes.

Abstract: A coolant flow control module, having a first outer housing, a first rotor located in the first outer housing, a second outer housing adjacent the first outer housing, and a second rotor disposed in the second outer housing. The second rotor is engaged with the first rotor such that the first rotor and second rotor rotate in unison. An actuator is connected to the first rotor, a first plurality of ports is integrally formed as part of the first outer housing, and a second plurality of ports is integrally formed as part of the second outer housing. The actuator rotates the first rotor and second rotor to at least one of a plurality of orientations such that fluid is able to flow through the first plurality of ports and the first rotor, and fluid is able to flow through the second plurality of ports and the second rotor.

Abstract: A pneumatic tool with a forward and reverse rotation structure includes a housing, a retaining member, two push buttons and a positioning pin. The housing includes an installation space. The retaining member is arranged inside the installation space to divide it into two push button accommodating cavities. The two push buttons movably slide inside the two push button accommodating cavities. The retaining member restricts the sliding ranges of the two push buttons. The positioning pin penetrates into the housing to allow the retaining member to be secured by the housing and the positioning pin. Accordingly, the retaining member is secured firmly while allowing it be removed for replacement and repair, the positioning pin is prevented from slippage, and any slipping off or snapping off of components between the sliding block of the push button and the slot wall of the retaining member can also be prevented.

Abstract: Methods and systems are provided for to methods and systems for distributing exhaust gas to a turbine, a turbocharger bypass, and an exhaust gas recirculation (EGR) line via a valve. In one example, a method may include selectively flowing exhaust gas, via a valve coupled to an exhaust passage, to one or more of an exhaust gas recirculation (EGR) passage, an exhaust turbine, and an exhaust catalyst via a bypass passage without flowing through the exhaust turbine based on engine operating conditions.

Abstract: An external support that routes the tubing of a reversing valve in such a manner that connection tubes extend from one end of the device and the treatment device tubes extend from the opposite end. The external support may provide guides that hold the tubing extending from the supported flat rotary switch type of valve so as to keep them from being pinch or kinked thereby ensuring free flow of blood.

Abstract: Provided are a control method of a heat pump system and a heat pump system. The heat pump system includes a throttling element and a four-way valve. The four-way valve has a first state in a case that the heat pump system operates for refrigerating and a second state in a case that the heat pump system operates for heating. The control method includes that: before the four-way valve is switched from the first state to the second state, A is compared with B, and switching of the state of the four-way valve is controlled and the opening degree of the throttling element is adjusted according to the comparison result, or switching of the state of the four-way valve is controlled according to the comparison result, or the opening degree of the throttling element is adjusted according to the comparison result.

Abstract: Disclosed is a four-way valve including a housing having a refrigerant filling chamber formed therein, a high pressure pipe hole formed on a bottom surface of the housing and coupled to a high pressure pipe through which refrigerant discharged from the compressor flows, a first pipe hole formed on an upper surface of the housing and coupled to a first pipe extending to a first heat exchanger, a second pipe hole formed on the upper surface of the housing and coupled to a second pipe extending to a second heat exchanger, a low pressure pipe hole formed on the upper surface of the housing and configured to allow the refrigerant to be collected to the compressor, and a switching guide configured to rotate to allow the low pressure pipe hole to selectively communicate with the first pipe hole or the second pipe hole.

Abstract: An actuator controls the operation of a valve member to achieve desired flow or no-flow states through different inlet ports of the valve in response to different types of input signals from one or more input sources. In some embodiments, the actuator drives the valve member along a first portion of a travel path to regulate flow through a first inlet port using analog or binary input signal(s) from a first input source, and drives the valve member along a second portion of the travel path to regulate flow through a second inlet port using analog or binary input signal(s) from a second input source. In some embodiments the actuator drives the valve member along the entire travel path to regulate flow through each of the first inlet port and the second inlet port responsive to an analog input signal from a single input source.

Abstract: A filtration system is disclosed, which comprises a filtration-element within a filtration chamber, and a valving device located exteriorly to the filtration chamber, for reversing the direction of fluid-flow through the filtration-element for backwashing. The valving device thus functions as a common valve for handling both filtration and backwash. The common valve is based on a linearly-movable plug located inside a valve housing which is communicable with the filtration chamber, with a source of fluid to be filtered, and with evacuation port for backwash fluid, through three respective openings in the valve housing, and is characterized by an uninterrupted bend-free flow-channel extending at least from exteriorly to an inlet opening of the valve housing, to the body of the filtration-element whenever the common valve is in a filtration mode of operation.

Abstract: A locking handle assembly for a rotary valve used in a hydraulic control system for a blow-out preventer used in oil and gas wells.

Abstract: A valve arrangement in particular four-way switch, for an adsorber station of an air separation plant, having a first valve device comprising a first gas inlet/gas outlet, a second valve device, comprising a second gas inlet/gas outlet, and a first connecting piece, which fluidically connects a first housing section of the first device to a second housing section of the second valve device, the first connecting piece has a third gas inlet/gas outlet. A second connecting piece, fluidically connects the first housing section to the second housing section, wherein the second connecting piece has a fourth gas inlet/gas outlet.

Abstract: A prover includes a piston supporting rod extending longitudinally through a cylinder, which cylinder receives and discharges a fluid to measure the volume and flow rate of the fluid by translation of the piston from the fluid receiving end to the fluid discharging end. Prover valve includes improved poppet valve disk shape that provides for smoother fluid flow, additional volume, and better sealing. Disk also includes angled wings and complimentary poppet seating to provide for better and more resilient seal. Retention ring may be fitted over poppet seal, and includes bolts that provide for removing retention ring to allow servicing of poppet seals (and replacement thereof) while tension remains on prover valve and rod.

Abstract: A vehicle heat pump system including a thermal loop, an eight-way valve, and a controller is provided. The thermal loop includes a compressor, a first portion, and a second portion. The first portion includes an outside heat exchanger. The second portion includes a cabin heat exchanger. The eight-way valve is downstream of the compressor and has a first position in which refrigerant flows within the portions in a cooling mode and a second position in which refrigerant flows within the portions in a heating mode. The controller switches the eight-way valve between the first and second positions. The outside heat exchanger operates as a condenser in the cooling mode and the eight-way valve directs refrigerant flow from the outside heat exchanger to the cabin heat exchanger.

Abstract: A hand-portable drying apparatus and method for use in a damp or waterlogged room, the apparatus including a housing having a carrying handle, the housing containing first and second airflow ducts arranged generally parallel to each other and having respective air inlet and air outlet ends, the apparatus further including means to force air through the ducts and to selectively heat it in at least one of the ducts, and valve means within the housing to selectively direct air from the first duct to the second duct whereby to move air from within the room received by the first duct back to the room via the second duct or to expel air from the room via the first duct to outside the room and draw in fresh air from outside the room via the second duct.

Abstract: An example valve includes: a piston movable between a neutral position and an actuated position, wherein in the neutral position: a second port of the valve is fluidly coupled to a first port, and a third port is fluidly decoupled from the second port; a solenoid actuator sleeve movable between an unactuated state and an actuated state, wherein in the actuated state, the solenoid actuator sleeve allows pilot fluid to apply a fluid force on a piston in a distal direction; a first feedback spring; and a second feedback spring disposed in series with the first feedback spring, wherein the first feedback spring and the second feedback spring cooperate to apply a biasing force in a proximal direction on the piston against the fluid force, wherein the piston is configured to move to the actuated position based on a relationship between the fluid force and the biasing force.

Abstract: A downhole circulation tool includes: a housing having an axially extending delivery bore for conveying a drilling mud flow therethrough, the housing having a circulation port for discharging drilling mud; and a valve member rotatably disposed within the housing, the valve member comprising a through-flow channel and a circulation channel. The valve member is rotatable between a through-flow position in which the through-flow channel is arranged to convey drilling mud flow from an upstream portion of the delivery bore to the downstream portion of the delivery bore, and a circulation position in which the circulation channel is arranged to convey drilling mud from the upstream portion of the delivery bore to the circulation port to discharge drilling mud from the housing. There is also disclosed a downhole tool comprising a unidirectional drive mechanism, an actuation element for a downhole tool, and a method of operating a downhole tool.

Abstract: This disclosure relates to methods of reversing blood flow using a blood flow reversal valve that includes a first member having a first passage and a second passage, and a second member having a first passage and a second passage. The first and second members are rotatably fixed relative to one another such that the first passage of the first member is aligned with the first passage of the second member and the second passage of the first member is aligned with the second passage of the second member. A flow directing element is disposed in the cavity and is moveable between a first position in which the first passage of the first member and the first passage of the second member are fluidly connected and a second position in which the first passage of the first member and the second passage of the second member are fluidly connected.

Abstract: A blend valve assembly including a plurality of ports, a stator having at least one fluid flow path defined therein that extends between at least one port of the plurality of ports in communication with the primary fluid media and at least one port of the plurality of ports in communication with an intake of a testing device, and a rotor comprising at least one fluid flow path defined therein. The rotor is movable between a series of positions such that the blend valve assembly is operable to provide the intake of the testing device with only the primary fluid media and to provide the intake of the testing device with a blend of the primary fluid media and the secondary fluid media.

Abstract: A system according to the present disclosure includes a start-stop module, a bypass valve control module, and a flapper valve control module. The start-stop module is configured to stop an engine of a vehicle independent of an ignition system of the vehicle. The bypass valve control module is configured to adjust a bypass valve to a bypass position to prevent engine coolant from flowing from the engine to a heater core of the vehicle when the engine is stopped independent of the ignition system. The flapper valve control module is configured to control a flapper valve to adjust an amount of airflow from an evaporator of the vehicle to a cabin of the vehicle through the heater core.

Abstract: A filter assembly for fluidic connection at a function port includes a connection base having a base inlet and a base outlet, the base inlet being fluidly connected to supply channels for supplying a fluid to cartridge inlets of at least two filter cartridges, and the base outlet being fluidly connected to discharge channels to discharge the fluid from cartridge outlets of the filter cartridges. The connection base with the base inlet and the base outlet has a fluidic connection structure corresponding to the filter cartridge with the cartridge inlet and the cartridge outlet such that the connection base or a filter cartridge is fluidly connected at the function port.

Abstract: There is provided a control valve including a cylindrical casing having an inlet port and a first outlet port for a fluid, and a valve accommodated in the casing to be rotatable around an axis extending in an axial direction of the casing and having a flow path communicating with the inlet port to allow the fluid to flow therethrough, wherein a first communication port communicating with the flow path and the first outlet port according to a rotational position of the valve is formed in the valve, and a fail opening configured to be opened and closed by a thermostat is formed in a portion of the casing facing the inlet port in an opening direction of the inlet port.

Abstract: An engine exhaust gas circuit includes a primary circuit in fluid communication with an intake of an engine and an outlet of the engine. The primary circuit conveys a gas from the outlet of the engine to the inlet of the engine. The primary circuit including a valve body having a rotary flap rotatably disposed in the valve body. A bypass circuit extends from a branch point intermediate the outlet of the engine and the valve body to the valve body.

Abstract: A rotary valve is disclosed. The valve comprises a drive shaft, a rotor coupled to the drive shaft, a least one bearing surface coupled to the rotor, a stator adjacent to the rotor, at least one solid bearing surface coupled to the stator, and at least one ring bearing surface coupled to the stator.

Abstract: A heat recovery variable-frequency multi-split heat pump system and a control method thereof. The system includes an outdoor unit and at least two indoor units. The system is a three-pipe heating recovery multi-split heat pump system designed on the basis of a four-way reversing valve, and one indoor unit thereof is provided with two electronic expansion valves and two heat exchangers so that any indoor unit in the system can operate independently under three working conditions of refrigeration, heating or heat recovery dehumidification. Under multi-split condition, the system can operate under six working conditions, namely, the full-refrigeration working condition, the full-heating working condition, the common-heat-recovery working condition, the common-heat-recovery-dehumidification working condition, the heat recovery dehumidification-refrigeration-combination working condition and the heat recovery dehumidification-heating-combination working condition.

Abstract: Slide valve (1), in particular for a waste heat recovery system of a combustion engine, having a valve housing (4), wherein an inlet passage (5) and an outlet passage (6) are formed in the valve housing (4). A substantially cylindrical slide (3) is guided in a longitudinally movable manner in a guide bore (20) in the valve housing (4), wherein the guide bore (20) can be connected hydraulically to the inlet passage (5) and to the outlet passage (6). A closing body (35, 35a) is arranged on the slide (3), wherein a slide seat (75, 75a) is formed between the guide bore (20) and the closing body (35, 35a). The guide bore (20) and the sliding body (35, 35a) form a sliding pair, wherein the sliding pair has the material combination steel-graphite or the material combination ceramic-graphite.

Abstract: A refrigerator includes a compressor. The refrigerator further includes a condenser. The refrigerator further includes a refrigerating chamber evaporator. The refrigerator further includes a freezing chamber evaporator. The refrigerator further includes a first capillary that is configured to reduce refrigerant pressure. The refrigerator further includes a second capillary that is configured to reduce refrigerant pressure. The refrigerator further includes a third capillary that is configured to reduce refrigerant pressure. The refrigerator further includes a 4-way valve that includes an inlet that is connected to the condenser, a first outlet that is connected to the first capillary, a second outlet that is connected to the second capillary, and a third outlet that is connected to the third capillary, and that is configured to selectively distribute refrigerant to at least one of the first capillary, the second capillary, or the third capillary.

Abstract: Directional control valves with blind shear rings are provided. In one embodiment, a valve includes a piston within an inner chamber of a hollow body having inlet and outlet ports in fluid communication with the inner chamber. The valve includes a shear seal ring positioned in the piston and seated against an interior surface within the hollow body. The shear seal ring includes an interior cavity for allowing fluid communication between the inlet port and the outlet port via the interior cavity depending on the position of the piston. Further, the valve includes a blind ring positioned in the piston. At least a portion of the blind ring is exposed to fluid via the interior cavity of the shear seal ring, and the blind ring prevents flow of fluid from the interior cavity of the shear seal ring through the blind ring. Additional systems, devices, and methods are also disclosed.

Abstract: A process for densifying an annular porous structure comprising flowing a reactant gas into an inner diameter (ID) volume and through an ID surface of the annular porous structure, flowing the reactant gas through an outer diameter (OD) surface of the annular porous structure and into an OD volume, flowing the reactant gas from the OD volume through the OD surface of the annular porous structure, and flowing the reactant gas through an ID surface of the annular porous structure and into the ID volume.

Abstract: The invention discloses a rotation-type flow path switching valve, which includes a driving component and a valve body component connected with a driving shaft. The valve body component includes a valve body, and a spool. The valve body component further includes: a driving disc, and a driven disc which is connected, by means of a first gap linkage mechanism, with the driving disc to transfer an axial movement within a preset swivel stroke of the driving disc. The driving shaft and the spool are connected by means of a second gap linkage mechanism to transfer the axial movement to the spool within a preset swivel stroke of the driving shaft. The valve body component further includes a spring which makes the spool abut against the valve body.

Abstract: A catalytic converter device for a stationary internal combustion engine includes at least one bracket for mounting the catalytic converter device on a carrier, and at least one catalyst substrate which can be releasably arranged in a housing of the catalytic converter device, the catalyst substrate having a cell density of at least 50 cpsi, preferably greater than 100 cpsi.

Abstract: A rotary valve is provided including a housing with an inner chamber having a first inlet, a first outlet, a second inlet, and a second outlet. A valve body is rotatably positioned in the housing. The valve body includes at least one isolated fluid pathway that, depending upon a rotational position of the valve body, provides at least one of a direct connection of one or more of the inlets to one or more of the outlets, or permits flow from at least an other one of the inlets or the outlets that are not in the direct connection created by the at least one isolated fluid pathway into or from the inner chamber. At least one actuator controls the position of the valve body.

Abstract: A system for warming the engine of a water-cooled vehicle by exchanging coolant with a warm vehicle or a storage tank of warmed coolant. The system utilizes a fitting that, in one position, allows for normal function of the cooling system of a vehicle, and in another position the fitting allows for fluid exchange with an outside source, such as another vehicle. The outside source can be a second vehicle equipped with a fitting or a standalone heater. Fluid transfer hoses are connected to each fitting to exchange coolant between vehicles.

Abstract: A refrigerant valve device may include a base provided with an inlet port, an outlet port and a valve seat face; a cover to section a valve chamber between the valve seat face and the cover; a valve body turnably disposed at a position shifted to a side of one port inside the valve chamber, the valve body being provided with a contact face sliding on the valve seat face; and a valve body drive mechanism to turn the valve body. The valve body drive mechanism may turn the valve body and thereby a refrigerant flowing passage from the inlet port to the outlet port through the valve chamber is switched at least to a first refrigerant flowing passage and to a second refrigerant flowing passage. The refrigerant flowing amount in the first refrigerant flowing passage may be smaller than a refrigerant flowing amount in the second refrigerant flowing passage.

Abstract: A valve for use in a gas turbine. The valve includes at least one valve body, at least first, second and third fluid delivery pipes positioned on the valve body, at least one outlet pipe positioned on the valve body and a rotatable spherical shutter inside the valve body (and including first and second distribution channels formed within the shutter so as to allow the outlet pipe to be selectively connected to one of the delivery pipes during rotation of the shutter.

Abstract: A system for warming the engine of a water-cooled vehicle by exchanging coolant with a warm vehicle or a storage tank of warmed coolant. The system utilizes a fitting that, in one position, allows for normal function of the cooling system of a vehicle, and in another position the fitting allows for fluid exchange with an outside source, such as another vehicle. The outside source can be a second vehicle equipped with a fitting or a standalone heater. Fluid transfer hoses are connected to each fitting to exchange coolant between vehicles.

Abstract: A solenoid valve including a spool received within a housing. The spool is configured to move to multiple positions within the housing. The housing includes supply ports, exhaust ports, and outlet ports. When the spool is in a specific location, two outlet ports are in fluid communication with each other.

Abstract: The invention relates to a valve (1) for regulating a gas flow in an EGR loop of a gas supply circuit of a vehicle engine, including a gas inlet (3), a first gas outlet (4) for directly feeding the gases into the supply circuit, and a second gas outlet (5) enabling said gases to flow into a pipe (6) passing through a cooler (2) before injecting said gases into said supply circuit, said valve (1) having a rotatable flap (7) capable of pivoting between a first position in which same blocks the second outlet (5) while at the same time opening the first outlet (4), and a second position in which same blocks the first outlet (4) while at the same time opening the second outlet (5). The main feature of a valve according to the invention is that the flap (7) includes a main flat body (11) capable of opening or closing the pipe (6) and that said pipe (6) has a flat rim (20), whereby the main body (11) of the flap (7) bears flatly against said rim (20) when said flap (7) is in the second position thereof.

Abstract: A package for holding an article, the package includes a liner and a construct attached to the liner. The liner includes an interior space for holding an article. The construct includes a plurality of panels that at least partially reinforce at a portion of the liner. The plurality of panels includes a top panel, a first side panel, a second side panel, and a bottom panel. The construct further includes a dispenser comprising dispensing features in at least one of the top panel and the bottom panel for allowing removal of the article from the package. The dispensing features include a dispenser panel at least partially defined by a tear line in the construct and for being at least partially removed to form a dispenser opening.

Abstract: This disclosure relates to blood flow reversal valves and related systems and methods. In certain aspects of the invention, a blood flow reversal valve includes a first member having a first passage and a second passage, and a second member having a first passage and a second passage. The first and second members are rotatably fixed relative to one another such that the first passage of the first member is aligned with the first passage of the second member and the second passage of the first member is aligned with the second passage of the second member. A flow directing element is disposed in the cavity and is moveable relative to the first and second members between a first position in which the first passage of the first member and the first passage of the second member are fluidly connected and a second position in which the first passage of the first member and the second passage of the second member are fluidly connected.

Abstract: The present invention provides a flow control valve which can control an amount of heat transfer medium bypassed or introduced into a heat exchange medium receiving portion according to temperature set by a user, and an air conditioner for an automobile equipped with the same, which can increase air-conditioning and cooling efficiency.

Abstract: The present invention provides a dual sensor differential pressure transmitter with a single fill fluid volume that intrinsically eliminates process and environmental performance influences, increases signal level while substantially reducing product costs.

Abstract: A flow channel switching valve includes a stator and a rotor inside an internal space of a housing, and includes a rotor drive portion that rotates the rotor while sliding the rotor on the stator by rotating a rotor drive shaft having, at a forefront, a rotor holding portion that holds the rotor. At a position below the rotor, the housing is provided with a liquid discharge portion that receives liquid leaking from between the stator and the rotor to guide the liquid outside the housing.

Abstract: A heat pump is provided including a plurality of lines having refrigerant flowing therethrough. A reversing valve is provided including a selector mechanism having a plurality of cavities formed therein and extending therethrough. A source of motion is coupled to the selector mechanism for movement of the selector mechanism. Each one of the plurality of cavities fluidly couples at least two of the plurality of lines. The selector mechanism is movable between a cooling mode and a heating mode so that the cavities fluidly couple different ones of the plurality of lines in each of the cooling mode and the heating mode. The selector mechanism will maintain its position with respect to the plurality of lines when the source of motion is de-energized, regardless of a pressure differential between different ones of the plurality of lines.

Abstract: A valve (10) may be used with an internal combustion engine exhaust breathing system (12) and may include a body (60), a partition (62), and a plate (66). The body (60) may define a first port (70) that has a first interior surface (76), and may also define a second port (82) that has a second interior surface (84). The partition (62) may be located within the body (60), may at least partially separate the first port (70) and the second port (82) from each other, and may define an opening (104). The plate (66) may be dimensioned to seat and seal against the opening (104) and against the first and second interior surfaces (76, 84). The plate (66) may rotate, depending on predetermined factors, between a first position and a second position.

Abstract: A control valve for hydraulic media is provided. The control valve includes a valve body having four ports. A first seat, a second seat, and a dual seat are positioned in the valve body between the ports. Two poppets, each including a disc and a cup, with a spring located therebetween, are arranged on a cylindrical pin with an enlarged engagement portion that is slidably supported within the valve body. A solenoid assembly movable in an axial direction within the valve body contacts the cylindrical pin and adjusts the position of the discs and cups of the poppets with respect to the seats of the valve body to minimize unwanted leakage between the ports. This configuration comprises four variable orifices that cooperate to provide controlled flow during different energizing phases of the solenoid assembly.

Abstract: Vitrectomy probes and system related thereto are disclosed herein. The disclosure describes various example vitrectomy probes having an adjustable cutting port size. Various example features are described for adjusting the size of the cutting port. Further, the disclosure provides examples for adjusting the size of the cutter port while the vitrectomy probe is in operation.

Abstract: A multi-way reversing valve includes a valve housing having a valve seat part in which a plurality of fluid in/out ports are formed; a valve member adapted to be rotated; and an actuator adapted to rotationally actuate the valve member. A fluid inlet port and/or a fluid outlet port is/are formed in the valve housing. A passage adapted to selectively place the fluid inlet port or the fluid outlet port in communication with the plurality of fluid in/out ports is formed within the valve member. Flow paths are reversed by rotating the valve member to selectively place the fluid inlet port or the fluid outlet port in communication with one of the plurality of in/out ports via the passage. The rotational axis line of the valve member is laterally eccentric relative to the rotational axis line of an output shaft of the actuator by a predetermined distance.

Abstract: A flow path switching valve arranged to rotate a main valve with an auxiliary valve to switch a cooling state and a heating state, which provides a reliable operation of the main valve by simplifying the rotation movement of the auxiliary valve and the main valve and provides reduced switching time. An outdoor heat exchanger-side pressure equalizing hole and an indoor heat exchanger-side pressure equalizing hole are formed at the main valve. An occluding portion for opening and closing of the pressure equalizing holes is formed at the auxiliary valve. The main valve is rotated 90 degrees by merely operating the auxiliary valve along one direction in forward or reverse direction to switch between the cooling state and the heating state.

Abstract: The present invention relates to a four-way reversing valve for refrigerating cycle system, in particular to an end cover for fitting with a valve body of a main valve of a four-way reversing valve, a four-way reversing valve using the same and an assembling method thereof. The end cover has a larger diameter section and a smaller diameter section sequentially provided in an axial direction, wherein an outer periphery of the larger diameter section of the end cover is adapted to be tightly connected with the valve body, and an end portion of the smaller diameter section of the end cover is adapted to be fitted with a piston of the main valve, so as to define an operating position of the piston, characterized in that the larger diameter section of the end cover has a frustum shape with a larger outer end and smaller inner end, or an end portion of the larger diameter section of the end cover has radially projected flange for abutting against and fitting with an end surface of the valve body.

Abstract: A movable valve element is provided so as to rotate about a predetermined shaft center. A first valve seat and a second valve seat are respectively arranged apart from the movable valve element with predetermined clearances on both sides of the movable valve element in a direction along the shaft center. A first sealing member is arranged around a communication path so as to seal a space inside the communication path from a space defined by the clearance on a side close to the first valve seat. A second sealing member is arranged around the communication path so as to seal the space inside the communication path from a space defined by the clearance on a side close to the second valve seat.