Tgk Co., Inc.

Nihon Radiator Co., Ltd.

Calsonic Corporation

Deutsche Controls Gmbh

Hisatoshi Hirota

Tokumi Tsugawa

Katsumi Koyama

Yuusuke Inoue

Shinji Saeki

Toshiyuki Shiota

Takeshi Kaneko

Tomokazu Nakazawa

Takashi Kobayashi

Yusuke Inoue

Isao Sendo

Masaichi Kawahata

Etsumi Nakano

Toyoyuki Hara

Masaaki Tonegawa

Michio Matsumoto

Kuniharu Baba

Naoyuki Ito

Masahide Ishikawa

Naoya Wanajo

Kouji Habu

Shiniji Saeki

A control valve includes: a body having valve holes for communicating an inlet port and the outlet ports together, respectively; valve elements for opening and closing valve sections by contacting and leaving the valve holes, respectively; a stepping motor having a rotor for driving the valve elements in the opening and closing directions of the valve sections; and a valve actuating member that drives the valve elements in the opening and closing directions of the valve sections by converting a rotational movement of the rotor around the axis line thereof into a translational movement of the valve actuating member in the axis line direction. The valve actuating member is supported by the rotor so as to be capable of making a translational movement of the valve actuating member in the axial direction with respect to the rotor, while a rotational movement with respect to the rotor is regulated.

Control valve driven by stepping motor

A control valve includes a body having a crankcase communicating port, a discharge chamber communicating port and a suction chamber communicating port, which are arranged in this order from one end side of the body, a solenoid, provided at the other end side of the body, for driving a main valve in accordance with the amount of current supplied, a power element, provided in an inner space surrounded by the body and the solenoid, capable of exerting the drive force to resist the solenoidal force created by a displacement of a pressure-sensing member of the power element, and a shaft by which the drive force of the power element is adjustable by adjusting the fixed position of one end side of the shaft, the shaft being fixed to one end of the body and the other end of the shaft being joined with the power element.

Control valve for variable displacement compressor

To provide a control valve for a variable displacement compressor using a diaphragm for a pressure-sensing section, which is capable of sensing suction pressure as absolute pressure. A core, a first plunger, and a spring of a solenoid are accommodated in a bottomed sleeve. A diaphragm is welded to an open end of the bottomed sleeve under vacuum atmosphere, whereby an assembly having a vacuum inside is formed. As a result, suction pressure Ps can be sensed as an absolute pressure with reference to a vacuum. The magnetic gap between the first plunger and the core is adjusted by the amount of press-fitting of the core into the bottomed sleeve, and the adjustment of load of the spring incorporated into the bottomed sleeve is made by deforming the bottom of the bottomed sleeve such that it is dented inward.

To provide a control valve for a variable displacement compressor, which is capable of stably operating in a pressure control area, and causing the compressor to quickly shift to operation with the minimum displacement. The control valve for a variable displacement compressor is capable of realizing stable pressure control, since a force applied to a valve element in a valve-closing direction increases when the valve element is in a pressure control area, and is balanced with a force applied to the valve element in a valve-opening direction by the pressure of refrigerant. Further, when the valve element moves past an end point of the pressure control area, the force applied to the valve element in the valve-closing direction decreases to thereby increase the valve-opening degree of a valve portion when the valve portion is fully open. Therefore, when a solenoid is not energized, it is possible to ensure a sufficient flow rate of refrigerant, thereby making it possible to cause the compressor to quickly shift to operation with the minimum displacement.

To provide a control valve which is capable of maintaining the minimum operation of a variable displacement compressor, by causing a valve section thereof to be fully opened, irrespective of the expanded or compressed state of a bellows, even when the suction pressure of the compressor is high. In the control valve for a variable displacement compressor, a bellows is disposed between a pressure-sensing piston and a core in a pressure-sensing chamber, and a pressing force-transmitting member which is fixed to a plunger is interposed between the pressure-sensing piston and the bellows. Then, a spring which urges the pressing force-transmitting member toward a valve section is disposed between the pressing force-transmitting member and the bellows. As a result, even if the bellows contracts due to high suction pressure Ps, the pressing force-transmitting member is held in a state being urged toward the valve section by the spring, which causes a valve element to be pushed upward via the pressure-sensing piston, to make the valve section fully open, whereby the minimum operation of the compressor can be maintained.

To provide a refrigerant relief device which releases refrigerant in a refrigeration cycle to the outside of a vehicle compartment, when the refrigerant releases into the vehicle compartment, or when there is a fear that the refrigerant releases into the vehicle compartment. A metal thin film is welded in advance to a body connected to piping of a refrigeration cycle such that it blocks a refrigerant inlet passage. When leakage of refrigerant into a vehicle compartment or collision of an automotive vehicle is detected, pulse current is applied to a coil of a solenoid, whereby a movable core is attracted to a fixed core. This causes a piercing rod fixed to the movable core to pierce the metal thin film with its pointed tip to make a hole through the metal thin film. When application of the pulse current is stopped, the piercing rod is returned to the standby position by a spring, so that the refrigerant is released to the outside of the vehicle compartment by passing through a conduit via the opened hole.

Refrigerant relief device

To provide an expansion valve having a low-pressure passage that is bent at right angles therein, which is reduced in untoward noise and noise of the flow of refrigerant generated when the refrigerant passes through the low-pressure passage. In an intersecting portion of a low-pressure passage, the axis of a port for introducing refrigerant returned from an evaporator, and the axis of a port for guiding out refrigerant having passed through a body block to a compressor are orthogonal to each other. A hole is formed in the body block in a direction of insertion of a shaft that transmits a driving force from a power element to a valve element, and a holder for holding the shaft. When holes coaxial with the ports, respectively, are formed by drills having the same diameter as that of the hole, the holes are formed in a manner such that the tip of one drill does not extend beyond the hole formed by the other drill, to make inner walls on an outer peripheral side along which refrigerant flows at an increased speed, smoothly continuous, without forming any recess or edge portion having a boundary portion with an angle equal to or smaller than a right angle.

Expansion valve

To reduce the degree of influence of differential pressure on a pilot valve of a constant flow rate expansion valve. The constant flow rate expansion valve comprises a restriction passage for restricting the flow rate of refrigerant introduced from a refrigerant inlet port, a main valve for controlling the flow rate of refrigerant having flowed out from the restriction passage for discharging the refrigerant to a refrigerant outlet port, a piston for actuating the main valve in the valve-opening/closing direction by the differential pressure between intermediate pressure on the inlet port side of the main valve and pressure in a pressure chamber formed on the opposite side of the main valve, and a pilot valve for sensing the differential pressure proportional to the flow rate of refrigerant flowing through the restriction passage, thereby controlling the pressure in the pressure chamber set by a solenoid. In parallel with the main valve are arranged the pilot valve, the pressure chamber, and a fixed orifice in series in the direction of flow of refrigerant. This makes it possible to apply only the same level of differential pressure as that of small differential pressure applied to opposite end faces of the piston to the pilot valve, thereby making it possible to lessen the degree of influence of differential pressure on the pilot valve.

Constant flow rate expansion value

A variable displacement compressor driven by an engine, such as an engine for driving an automotive vehicle is used as a compressor, and the capacity of the compressor is controlled by a capacity control valve such that the differential pressure between discharge pressure and suction pressure of refrigerant becomes equal to a predetermined differential pressure determined by an external signal. Pressure substantially equal to pressure applied across the compressor is applied across the ejector, and therefore to control the differential pressure across the compressor is to control the differential pressure across the ejector. A differential pressure valve disposed between a gas-liquid separator and an evaporator is set to a differential pressure approximately proportional to the differential pressure across the ejector.

Refrigeration cycle

The object is to provide a capacity control valve for a variable displacement compressor, which is not adversely affected by pressure from a pressure-regulating chamber. The cross-sectional area of a valve hole of a high pressure-side valve seat for introducing discharge pressure Pd of a variable displacement compressor into a pressure-regulating chamber is A, the cross-sectional area of a valve hole of a low pressure-side valve seat for introducing pressure Pc(=Pc) of the pressure-regulating chamber into a suction chamber is B, and the average cross-sectional area of a refrigerant passage assumed when a low-pressure valve element is open during most of control time of actual operation is b. A and B are set to A&#x3c;B to make the effective pressure receiving area (&#x2245;A) of the high pressure-side valve and the effective pressure receiving area (&#x2245;B&#x2212;b) of the low pressure-side valve approximately equal.

Capacity control valve for variable displacement compressor

To provide a fluid control valve which is capable of preventing or suppressing degradation of the accuracy of flow rate control dependent on the lift amount of a valve element from a valve seat. An expansion valve is configured such that a valve portion and a valve portion integrally formed with a valve element move to and away from a valve seat and a valve seat, respectively, simultaneously. Further, the expansion valve is configured such that a flow passage cross-section formed by a gap between the valve portion and the valve seat, and a flow passage cross-section formed by a gap between the valve portion and the valve seat have approximately the same size when the expansion valve is open. As a result, it is possible to almost cancel the influence of changes in effective pressure-receiving areas acting on the respective valve elements when the expansion valve is open, on the pressure balance, thereby making it possible to prevent degradation of the accuracy of flow rate control dependent on the lift amount of the valve elements.

Fluid control valve

To provide a constant differential pressure valve which is compact in size and can be realized at low cost. In the constant differential pressure valve according to the present invention, a pipe forming a body thereof not only accommodates internal structures, such as a differential pressure control mechanism, a movable core, and a fixed core, but also serves as part of piping of a refrigeration cycle. Further, a solenoid section including a solenoid coil is disposed outside the pipe in a manner surrounding the same. Therefore, substantial integration of the differential pressure control mechanism into the piping of the refrigeration cycle can be achieved, which makes the entire constant differential pressure valve very simple in construction. As a result, reduction of the size of the constant differential pressure valve and resultant reduction of material costs and manufacturing costs can be achieved, which makes it possible to achieve low costs of the constant differential pressure valve.

Constant differential pressure valve

A constant flow rate expansion valve includes a refrigerant passage having a fixed flow path cross-sectional area smaller than that of a refrigerant inlet, a differential pressure control valve for controlling the differential pressure (P&#x2212;P) between an inlet pressure Pand an intermediate pressure Pgenerated by refrigerant flowing through the refrigerant passage to be constant, and a solenoid capable of setting the differential pressure by the value of an electric current externally supplied. In the differential pressure control valve, a piston and a valve element integrally formed with each other sense the differential pressure (P&#x2212;P), change a gap between the valve element and a valve seat such that the differential pressure is held constant, and adiabatically expand the refrigerant at the gap.

Constant flow rate expansion valve

The object of the present invention is to provide a solenoid valve-equipped expansion valve simplified in construction. A common valve element in which a valve element of an expansion valve and a valve element of a stop valve are integrally formed as a unitary member is disposed such that the common valve element can be axially movably guided by a shaft having the driving force of a power element transmitted thereto. A first core of a solenoid, holding the common valve element, is urged by a spring such that the common valve element is seated on a valve seat. When the solenoid is energized, the first core holding the common valve element is attracted by a second core rigidly fixed to the shaft such that the common valve element operates with the shaft in an interlocked fashion. As a result, when the solenoid is deenergized, the common valve element can function as a stop valve, whereas when the solenoid is energized, the common valve element can function as an expansion valve.

Solenoid valve-equipped expansion valve

An object of the invention is to provide a variable displacement compressor which is capable of using a solenoid control valve which does not require a large solenoid force. The compressor is configured such that an electromagnetic proportional flow rate control valve is arranged in a refrigerant passage leading from a discharge chamber to a condenser, that a differential pressure regulating valve is arranged in a refrigerant passage leading from the discharge chamber to a crank chamber, and that a fixed orifice is arranged in a refrigerant passage leading from the crank chamber to a suction chamber, whereby the differential pressure regulating valve senses a differential pressure Pd, Pd' generated across the electromagnetic proportional flow rate control valve, for control of pressure introduced into the crank chamber. Due to this configuration, the differential pressure regulating valve controls pressure Pc in the crank chamber such that the difference of pressure of refrigerant before and after passing through a restriction having openness set by the electromagnetic proportional flow rate control valve becomes constant, which makes the flow rate Qd of discharged refrigerant constant irrespective of changes in the engine rotational speed, etc. Since the differential pressure can be controlled by a small solenoid force, the variable displacement compressor can be made compact in size.

Growing community of inventors

Tokyo, Japan

Hisatoshi Hirota