Abstract: To provide an expansion device which shortens cool down time when an automotive air conditioner is started under a high-load condition. An expansion device having a differential pressure control valve is configured such that a temperature-sensing actuator (shape-memory alloy spring) is disposed at an refrigerant outlet of the expansion device, and when an air conditioner is started under a high-load condition in which the temperature of refrigerant at the refrigerant outlet is high, the shape-memory alloy spring senses the high temperature, to urge a spring determining a valve-opening point of the differential pressure control valve, whereby the differential pressure control valve is opened in advance or placed in a state capable of opening in response to a very low differential pressure, thereby making it possible to cause refrigerant to flow at a large flow rate until the temperature of refrigerant at the refrigerant outlet is lowered to a temperature assumed when the air conditioner functions.

Abstract: To provide an expansion device which controls high pressure-side pressure such that the pressure does not exceed a predetermined pressure in terms of absolute pressure, while operating in response to differential pressure between pressure at an inlet thereof and pressure at an outlet thereof. An expansion device comprises an orifice for expanding refrigerant, a valve element disposed on a downstream side of a valve hole and urged by a shape-memory alloy spring in a valve-opening direction, a shaft disposed to extend through the valve hole and having one end thereof rigidly fixed to the valve element, and a spring provided at the other end of the shaft, for receiving load generated by differential pressure between pressure of refrigerant at an inlet of the device and pressure of refrigerant at an outlet thereof, in a valve-opening direction.

Abstract: To prevent refrigerant in a refrigeration cycle from releasing into a vehicle compartment, in large amounts, due to breakage of an evaporator disposed on a compartment side or piping thereto. An expansion device is formed by an expansion valve that supplies throttled and expanded refrigerant to an evaporator, an electromagnetic valve connected in series to the expansion valve, and a check valve that prevents backflow of refrigerant flowing out of the evaporator, and a release-to-atmosphere device is provided in low-pressure piping connected to the compressor, for allowing the refrigerant therein to be released into the atmosphere.

Abstract: An expansion device which is capable of reducing generation of untoward noise due to vibration of a valve element and suppressing a valve element suction phenomenon which occurs when high-pressure refrigerant flows through a variable orifice formed between a valve seat and the valve element. A damper chamber is formed by a cylinder formed in a housing formed with a valve seat, a piston integrally formed with a valve element, and an adjustment screw. When the valve element undergoes a sudden change in pressure of introduced refrigerant, the volume of the damper chamber changes to accommodate sudden motion of the valve element, whereby vibration of the valve element is suppressed, to reduce generation of untoward noise. The ratio (b/a) of the valve element diameter (b) of the valve element to the port diameter (a) of a valve hole is set to a value not larger than 1.

Abstract: A differential pressure valve simplified in construction includes a piston integrally formed with a main valve element and arranged on the upstream side of a main valve to define a chamber for introducing refrigerant from an inlet port. The piston has an orifice and a refrigerant passage for communicating with a chamber on a back surface side of the piston. The chamber is configured such that it can be connected, via a refrigerant passage and a pilot valve element, to a chamber on the downstream side of the main valve, which communicates with an outlet port.

Abstract: To provide an outflow prevention device which is capable of preventing refrigerant from flowing out into a vehicle compartment even when an evaporator has ruptured. The outflow prevention device comprises a shut valve arranged in a passage via which refrigerant introduced into a shut valve inlet from an expansion device is allowed to flow to the evaporator, and a check valve arranged in a passage via which refrigerant returned from the evaporator is allowed to flow to an accumulator. A chamber behind a piston fixed to a plug holding a valve sheet and a chamber on a downstream side of the check valve are communicated with each other via a bypass passage, so that differential pressure generated across the check valve by flow of refrigerant through the same can be applied to the shut valve to open and close the same.

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 prevent refrigerant in a refrigeration cycle from releasing into a vehicle compartment, in large amounts, due to breakage of an evaporator disposed on a compartment side or piping thereto. An expansion device is formed by an expansion valve that supplies throttled and expanded refrigerant to an evaporator, an electromagnetic valve connected in series to the expansion valve, and a check valve that prevents backflow of refrigerant flowing out of the evaporator, and a release-to-atmosphere device is provided in low-pressure piping connected to the compressor, for allowing the refrigerant therein to be released into the atmosphere.

Abstract: To provide an expansion device that is configured compact in size and capable of effectively preventing an abnormal rise in pressure within the expansion device caused by the differential pressure across the expansion device. An expansion device according to the present invention cancels part of refrigerant pressure by a pressure-canceling structure. More specifically, by the amount of pressure received by a valve-closing pressure-receiving surface, the elastic force required of a spring can be reduced. As a result, a small-sized spring can be employed as the spring, and the entire expansion device can be made compact in construction. Further, when the differential pressure across the expansion device has become equal to or higher than a predetermined value, a relief mechanism enables refrigerant flowing in from the upstream side to escape into a passage other than a refrigerant passage through a valve element.

Abstract: To provide a four-way solenoid valve having a three-way solenoid valve of which non-concentricity between a valve element and a valve hole is small, if any. A core of a three-way solenoid is integrally formed with a refrigerant passage extending axially therethrough, an annular projection forming a valve seat, and a guide for guiding reciprocating motion of a needle forming a valve element. A plug closing a cylinder of a body to define the pressure control chamber is also integrally formed with a valve seat and a guide for guiding reciprocating motion of a needle forming a valve element associated with the valve seat. This causes the needles to be seated on the valve seats associated therewith in respective states guided by the guides substantially concentric with the valve holes, which makes it possible to impart sufficient sealing properties to the valve portions when each valve is closed.

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 refrigerating cycle is capable of performing both an operation in which the maximum cooling power is desired to be unleashed and an operation in which the most excellent performance coefficient is attained. A refrigerating cycle is configured such that a differential pressure-regulating valve forming a pressure-reducing device is arranged between a condenser and a receiver. As a result, by setting the differential pressure regulated by the differential pressure-regulating valve 3 to 0, it is possible to cause the refrigerating cycle to perform an operation in which the maximum cooling power is desired to be unleashed, whereas by setting the same to a desired value, it is possible to cause the same to perform an operation in which an excellent performance coefficient is attained.

Abstract: To provide an outflow prevention device which is capable of preventing refrigerant from flowing out into a vehicle compartment even when an evaporator has ruptured.

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 four-way solenoid valve having a three-way solenoid valve of which non-concentricity between a valve element and a valve hole is small, if any. A core of a three-way solenoid is integrally formed with a refrigerant passage extending axially therethrough, an annular projection forming a valve seat, and a guide for guiding reciprocating motion of a needle forming a valve element. A plug closing a cylinder of a body to define the pressure control chamber is also integrally formed with a valve seat and a guide for guiding reciprocating motion of a needle forming a valve element associated with the valve seat. This causes the needles to be seated on the valve seats associated therewith in respective states guided by the guides substantially concentric with the valve holes, which makes it possible to impart sufficient sealing properties to the valve portions when each valve is closed.

Abstract: To provide a differential pressure valve simplified in construction. A piston integrally formed with a main valve element is arranged on the upstream side of a main valve formed by the main valve element and a main valve seat, to thereby define a chamber for introducing refrigerant from an inlet port. The piston is provided with an orifice and a refrigerant passage for the communicating with a chamber on a back surface side of the piston. The chamber on the back surface side of the piston is configured such that it can be connected, via a refrigerant passage and a pilot valve formed by a pilot valve seat and a pilot valve element, to a chamber on the downstream side of the main valve, which communicates with an outlet port. Refrigerant from the inlet port is supplied the pilot valve via the orifice, and the refrigerant passages.

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: An expansion valve of the degree-of-supercooling control type can be easily adjusted when assembling the degree of supercooling of a high-pressure refrigerant control to be held constant if an exerting force adjusting member is used for finely adjusting the exerting force. If either a throttling portion or a valve seat is formed with the exerting force adjusting member, a simple and compact design or construction can be achieved.

Abstract: A refrigerating cycle is capable of performing both an operation in which the maximum cooling power is desired to be unleashed and an operation in which the most excellent performance coefficient is attained.

Abstract: In a main valve having a solenoid pilot operated valve, a movable core and a hollow plunger are movably received in a sleeve extending from a pressure control chamber through an electromagnetic coil. The plunger is structurally separated from a main valve member. A shaft is slidably received in the plunger. One end of the shaft carries a pilot valve member. A spring engages at the plunger and the shaft such that the free end of the shaft projects a predetermined length beyond an end face of the plunger. As long as the coil is deenergized, the spring separates the pilot valve member from a pilot valve seat. As soon as the coil is energized, the plunger is attracted to the core, the shaft is displaced in relation to the plunger, and the pilot valve member projecting from the lower end of the plunger closes the pilot valve seat. Due to the developing pressure difference, the main valve is closed and kept in a closed state.