Abstract: A valve element has a packing material, whose one side surface touches and leaves a valve seat as a sealing surface, and a support member, which is driven in opening and closing directions of a valve section by actuating an actuator. The support member includes a supporting surface, which is in contact with a side surface of the packing material opposite to the sealing surface of the packing material, and an engagement part, which supports a peripheral edge part of the packing material in a manner such that the engagement part is engaged with the peripheral edge part. A ring-shaped fluid flow passage is formed between the supporting surface of the support member and the packing material, and this fluid flow passage communicates with an upstream passage.

Abstract: A first expansion valve is provided in a first refrigerant circulation passage through which the refrigerant discharged from a compressor is able to circulate by passing sequentially through an external heat exchanger and an evaporator and returning to the compressor. A second expansion valve is provided in a second refrigerant circulation passage through which the refrigerant discharged from the compressor is able to circulate by passing sequentially through an auxiliary condenser and the external heat exchanger and returning to the compressor. The second expansion valve regulates the valve opening degree such that the refrigerant state at an inlet side of the compressor during a heating operation is in a range where the dryness of refrigerant is greater than or equal to 0.9 and the superheat of refrigerant is less than or equal to 5° C.

Abstract: A piston is configured by a piston body and a support such that the piston is divided, along a direction of axis line, into the piston body, which is formed integrally with a valve element, and the support, which is provided separately from the valve element. A piston ring, which slides along a body, is held between the piston body and the support. The piston body is constantly in contact with one side face of the piston ring, and the support is constantly in contact with the other side face of the piston ring.

Abstract: A pilot valve element includes a metallic pilot valve body formed integrally with a plunger, a flexible sealing member, fitted on a tip of the pilot valve body, which touches and leaves a pilot valve seat, and a stopper for restricting the displacement of the pilot valve element relative to a driven member in a manner such that the sealing member is stopped in a direction of axis line after the sealing member has seated on a pilot valve seat. The stopper is configured such that the pressure-receiving diameter of the sealing member, which receives a pressure difference between an upstream side and a downstream side of the pilot valve, remains unchanged from when the sealing member comes in contact with the pilot valve seat until when the sealing member is stopped by the stopper with the result that the sealing member has completely seated on the pilot valve seat.

Abstract: A piston is configured by a piston body and a support such that the piston is divided, along a direction of axis line, into the piston body, which is formed integrally with a valve element, and the support, which is provided separately from the valve element. A piston ring, which slides along a body, is held between the piston body and the support. The piston body is constantly in contact with one side face of the piston ring, and the support is constantly in contact with the other side face of the piston ring.

Abstract: A valve element has a packing material, whose one side surface touches and leaves a valve seat as a sealing surface, and a support member, which is driven in opening and closing directions of a valve section by actuating an actuator. The support member includes a supporting surface, which is in contact with a side surface of the packing material opposite to the sealing surface of the packing material, and an engagement part, which supports a peripheral edge part of the packing material in a manner such that the engagement part is engaged with the peripheral edge part. A ring-shaped fluid flow passage is formed between the supporting surface of the support member and the packing material, and this fluid flow passage communicates with an upstream passage.

Abstract: A pilot valve element includes a metallic pilot valve body formed integrally with a plunger, a flexible sealing member, fitted on a tip of the pilot valve body, which touches and leaves a pilot valve seat, and a stopper for restricting the displacement of the pilot valve element relative to a driven member in a manner such that the sealing member is stopped in a direction of axis line after the sealing member has seated on a pilot valve seat. The stopper is configured such that the pressure-receiving diameter of the sealing member, which receives a pressure difference between an upstream side and a downstream side of the pilot valve, remains unchanged from when the sealing member comes in contact with the pilot valve seat until when the sealing member is stopped by the stopper with the result that the sealing member has completely seated on the pilot valve seat.

Abstract: A first expansion valve is provided in a first refrigerant circulation passage through which the refrigerant discharged from a compressor is able to circulate by passing sequentially through an external heat exchanger and an evaporator and returning to the compressor. A second expansion valve is provided in a second refrigerant circulation passage through which the refrigerant discharged from the compressor is able to circulate by passing sequentially through an auxiliary condenser and the external heat exchanger and returning to the compressor. The second expansion valve regulates the valve opening degree such that the refrigerant state at an inlet side of the compressor during a heating operation is in a range where the dryness of refrigerant is greater than or equal to 0.9 and the superheat of refrigerant is less than or equal to 5° C.

Abstract: To provide a differential pressure valve which is capable of suppressing generation of noise when a variable displacement compressor is being operated at its minimum displacement. A hollow cylindrical protruding portion of a valve element, which is disposed in a manner surrounding a hollow cylindrical valve seat, is configured to have two windows formed at circumferentially one-sided locations as openings of a sleeve valve. As a result, the difference is generated between areas of regions of an inner peripheral surface of the hollow cylindrical protruding portion circumferentially separated by the windows, to thereby make transverse load unbalanced, so that the valve element performs opening and closing operations always in a state in which the hollow cylindrical protruding portion is transversely pressed against the hollow cylindrical valve seat.

Abstract: The object of the present invention is to provide a solenoid control valve simple in construction and low in cost, realized by reducing the number of component parts, eliminating screw-joined portions, and minimizing the use of rubber O rings. A valve hole of a pilot valve, a hole of a bearing for supporting one end of a shaft of a solenoid, and a fitting hole in which is fitted one end of a sleeve, are formed along the same axis in a body. This makes it possible to accurately establish the concentricity of movable components of the solenoid when the sleeve is fitted in the fitting hole, and hence, a pilot valve element can be integrally formed with the shaft. Set values for a main valve and the pilot valve are adjusted by adjusting the amounts of insertions of a press-fit member and a bearing by press-fitting.

Abstract: A four-way switching valve free from leakage of a refrigerant is disclosed. The valve includes two three-way switching valves arranged side by side, each having a pressure-regulating chamber, a piston, and a plug coaxially arranged. One of the pressure-regulating chambers selectively communicates with a low-pressure chamber or a high-pressure chamber via a three-way solenoid valve. The other pressure-regulating chamber communicates with another chamber in which the pressure increases or decreases as the pressure within one of the pressure-regulating chambers decreases or increases. As a result, refrigerant leakage is prevented, in turn preventing degradation of the refrigerating power of a system.

Abstract: To provide a small-sized and low-cost proportional solenoid valve which is capable of controlling a bidirectional fluid flow. A core is fixed in a pipe, and a hollow shaft having an extreme end thereof closed by a valve seat and a portion adjacent thereto formed with valve holes is fixed in the core. Within the pipe, there are arranged a hollow cylindrical valve element axially movable using the shaft as a guide and urged in a direction away from the core by a spring, for opening and closing the valve holes, and a plunger, while outside the pipe, there is arranged a solenoid coil. The proportional solenoid valve has a body formed by the pipe, and the component parts for opening and closing the valve are arranged within the pipe, so that it is possible to reduce the size of the proportional solenoid valve, the number of component parts, and machining costs and material costs, which contributes to reduction of costs of the valve.

Abstract: The object of the present invention is to provide a solenoid control valve simple in construction and low in cost, realized by reducing the number of component parts, eliminating screw-joined portions, and minimizing the use of rubber O rings. A valve hole of a pilot valve, a hole of a bearing for supporting one end of a shaft of a solenoid, and a fitting hole in which is fitted one end of a sleeve, are formed along the same axis in a body. This makes it possible to accurately establish the concentricity of movable components of the solenoid when the sleeve is fitted in the fitting hole, and hence, a pilot valve element can be integrally formed with the shaft. Set values for a main valve and the pilot valve are adjusted by adjusting the amounts of insertions of a press-fit member and a bearing by press-fitting.

Abstract: To provide a small-sized and low-cost proportional solenoid valve which is capable of controlling a bidirectional fluid flow. A core is fixed in a pipe, and a hollow shaft having an extreme end thereof closed by a valve seat and a portion adjacent thereto formed with valve holes is fixed in the core. Within the pipe, there are arranged a hollow cylindrical valve element axially movable using the shaft as a guide and urged in a direction away from the core by a spring, for opening and closing the valve holes, and a plunger, while outside the pipe, there is arranged a solenoid coil. The proportional solenoid valve has a body formed by the pipe, and the component parts for opening and closing the valve are arranged within the pipe, so that it is possible to reduce the size of the proportional solenoid valve, the number of component parts, and machining costs and material costs, which contributes to reduction of costs of the valve.

Abstract: A four-way switching valve free from leakage of a refrigerant. A pressure-regulating chamber is switchably connected to a low-pressure chamber or a high-pressure chamber by a three-way solenoid valve, and a pressure-regulating chamber is communicated with a chamber by a tube. When the three-way solenoid valve connects the pressure-regulating chamber to the low-pressure chamber, a plug is urged by the high pressure, thereby permitting port A and a port B to communicate with each other, while inhibiting the port B and a port D from communicating with each other. The pressure within the chamber is increased to thereby increase the pressure within the pressure-regulating chamber. Consequently, a plug is urged by a piston to thereby inhibit the port A and a port C from communicating with each other, and permitting the port C and the port D to communicate with each other.

Abstract: An expansion valve adapted to achieve a stable operation in case of variations of the pressure of a high-pressure refrigerant is actuated by a power element transmitting an opening force to a valve body via a rod located between the power element and the power body by applying couple forces to the rod and generating a retarding force for the rod while the rod is guided in the direction of its shaft line