Patents Assigned to TGK Co., Ltd.
  • Publication number: 20080185545
    Abstract: To enable a control valve to be easily mounted, not by bolt fastening. A thread portion is formed in a mounting hole of a compressor, in which a control valve is to be mounted, and as for the control valve as well, a thread portion mating with the thread portion in the mounting hole is threadedly formed on a yoke surrounding a coil of a solenoid of the control valve. A gasket is disposed between a flange portion of the control valve, formed in a manner opposed to a stepped portion inside the mounting hole, and the stepped portion inside the mounting hole. The yoke is provided in a manner pivotally movable with respect to the flange portion having the gasket disposed thereon, and is configured to be brought into contact with the flange portion in a direction of insertion of the control valve.
    Type: Application
    Filed: July 6, 2007
    Publication date: August 7, 2008
    Applicant: TGK CO., LTD.
    Inventor: Hisatoshi HIROTA
  • Publication number: 20080141691
    Abstract: An automotive air conditioner which is capable of efficiently disposing an internal heat exchanger, and enabling the air conditioner to perform an efficient operation. A thermostatic expansion valve is accommodated in a casing directly connected to the refrigerant outlet of an evaporator. The inlet of the expansion valve and a pipe for receiving high-pressure liquid refrigerant are connected to each other within the casing. The outlet of the expansion valve and the refrigerant inlet of the evaporator are connected to each other within the casing. The internal heat exchanger for performing heat exchange between high-pressure refrigerant delivered to the inlet of the expansion valve and low-pressure refrigerant returning to a compressor is connected between the casing and a pipe joint disposed in a firewall.
    Type: Application
    Filed: December 13, 2007
    Publication date: June 19, 2008
    Applicant: TGK CO., LTD.
    Inventor: Hisatoshi HIROTA
  • Patent number: 7386987
    Abstract: 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.
    Type: Grant
    Filed: March 18, 2005
    Date of Patent: June 17, 2008
    Assignee: TGK Co., Ltd.
    Inventor: Hisatoshi Hirota
  • Patent number: 7387501
    Abstract: 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.
    Type: Grant
    Filed: March 11, 2005
    Date of Patent: June 17, 2008
    Assignee: TGK Co., Ltd.,
    Inventor: Hisatoshi Hirota
  • Patent number: 7381031
    Abstract: A control valve for a variable displacement compressor that is mounted on the variable displacement compressor to control pressure within a hermetic crankcase to thereby change the discharging capacity of a refrigerant.
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: June 3, 2008
    Assignee: TGK Co., Ltd.
    Inventors: Takeshi Kawaguchi, Morimitsu Kajiwara
  • Publication number: 20080053125
    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.
    Type: Application
    Filed: August 24, 2007
    Publication date: March 6, 2008
    Applicant: TGK CO., LTD.
    Inventors: Ryosuke SATAKE, Masaaki TONEGAWA, Tomohiro YUASA, Tokumi TSUGAWA
  • Publication number: 20080006331
    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.
    Type: Application
    Filed: June 14, 2007
    Publication date: January 10, 2008
    Applicant: TGK Co., Ltd.
    Inventors: Toshiyuki Shiota, Yoichi Miura
  • Patent number: 7316118
    Abstract: 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.
    Type: Grant
    Filed: July 14, 2004
    Date of Patent: January 8, 2008
    Assignee: TGK Co., Ltd.
    Inventors: Hisatoshi Hirota, Michio Matsumoto
  • Publication number: 20070283717
    Abstract: To improve the manufacturing efficiency of a body, and reduce the manufacturing cost of an expansion valve. A body accommodating a valve section is formed, using forming dies, such as die-casting dies, integrally with an inlet port for introducing refrigerant, an outlet port for delivering expanded refrigerant, a male thread, and has a power element connected thereto by the male thread. This eliminates a necessity of subjecting the body to fabrication, for forming the inlet port, the outlet port, a valve hole, a hole for receiving therein a valve element and set value-adjusting members, a hole for receiving therein a shaft which transmits an actuating force dependent on temperature sensed by the power element to the valve element, and further the male screw. Therefore, the manufacturing efficiency of the body is improved, and the manufacturing cost of the expansion valve can be reduced.
    Type: Application
    Filed: June 6, 2007
    Publication date: December 13, 2007
    Applicant: TGK Co., Ltd.
    Inventor: Hisatoshi Hirota
  • Publication number: 20070266731
    Abstract: To reduce the number of refrigerant external leak-prone spots, in a portion where an expansion valve is mounted. A casing is joined to a refrigerant outlet of an evaporator, and a low-pressure pipe extending to a compressor is connected to the casing by a pipe clamp. An expansion valve is disposed within the casing. Within the casing, an inlet port of the expansion valve and a high-pressure pipe are connected to each other, and an outlet port of the expansion valve and an inlet pipe of an evaporator are connected to each other. This limits the portions of the expansion valve which can cause refrigerant external leakage to portions connected by the pipe clamp.
    Type: Application
    Filed: May 15, 2007
    Publication date: November 22, 2007
    Applicant: TGK CO., LTD.
    Inventor: Hisatoshi Hirota
  • Publication number: 20070264134
    Abstract: To provide a control valve for variable displacement compressor employing ON/OFF control, which is capable of taking measures for occurrence of an abnormally high pressure. When a solenoid is OFF, a spring causes a movable core to move a stopper in a direction away from a stationary core and to thereby separate a shaft fixed to the stopper from a valve seat, resulting in opening the control valve. When the solenoid is ON, the movable core is attracted by the stationary core by a stroke longer than that of the shaft, and a spring causes the shaft to seat on the valve seat, resulting in closing the control valve. If a discharge pressure Pd increases to an abnormally high pressure, a differential pressure between the discharge pressure Pd and a pressure Pc in a crankcase pushes the shaft while compressing the spring, so that the discharge pressure Pd flows out to the crankcase.
    Type: Application
    Filed: July 13, 2007
    Publication date: November 15, 2007
    Applicant: TGK CO., LTD.
    Inventor: Hisatoshi Hirota
  • Publication number: 20070209387
    Abstract: To provide an expansion valve which is capable of preventing the temperature of refrigerant compressed by a compressor from becoming too high, when a refrigeration load on a refrigeration cycle using an internal heat exchanger is high. A thermostatic expansion valve is applied to a refrigeration cycle provided with an internal heat exchanger that performs heat exchange between high-temperature refrigerant flowing from a condenser to the expansion valve and low-temperature refrigerant flowing from an evaporator to a compressor via the expansion valve. The expansion valve comprises a bypass passage or for causing refrigerant in a high-pressure refrigerant inlet or a low-pressure refrigerant outlet to flow to the downstream side of a temperature-sensing section, such that moist refrigerant is mixed with refrigerant whose degree of superheat is controlled by the expansion valve.
    Type: Application
    Filed: February 28, 2007
    Publication date: September 13, 2007
    Applicant: TGK CO., LTD.
    Inventor: Hisatoshi Hirota
  • Patent number: 7263857
    Abstract: 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.
    Type: Grant
    Filed: February 28, 2006
    Date of Patent: September 4, 2007
    Assignee: TGK Co., Ltd.
    Inventor: Hisatoshi Hirota
  • Publication number: 20070180854
    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.
    Type: Application
    Filed: February 2, 2007
    Publication date: August 9, 2007
    Applicant: TGK CO., LTD.
    Inventors: Hisatoshi Hirota, Tokumi Tsugawa, Masaaki Tonegawa, Ryosuke Satake
  • Publication number: 20070157648
    Abstract: In a control valve for a variable displacement compressor, for controlling the discharge flow rate of refrigerant to be constant, to dispense with a check valve in a refrigerant outlet port of the compressor. The control valve includes a first control valve that controls the passage cross-sectional area of a refrigerant passage through which refrigerant passes from a discharge chamber of the compressor to a refrigerant outlet port thereof, and a second control valve that controls the flow rate of refrigerant allowed to flow from the discharge chamber to a crankcase such that a differential pressure (Pdh?Pdl) across the first control valve generated by the refrigerant passing therethrough becomes constant. The control valve is configured such that when a solenoid section is not energized, a first valve element is engaged with a piston to forcibly fully open the second control valve.
    Type: Application
    Filed: January 5, 2007
    Publication date: July 12, 2007
    Applicant: TGK CO., LTD.
    Inventor: Hisatoshi Hirota
  • Patent number: 7207186
    Abstract: 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.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: April 24, 2007
    Assignee: TGK Co., Ltd.
    Inventor: Hisatoshi Hirota
  • Patent number: 7165421
    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.
    Type: Grant
    Filed: April 4, 2005
    Date of Patent: January 23, 2007
    Assignee: TGK Co., Ltd.
    Inventor: Tokumi Tsugawa
  • Patent number: 7121811
    Abstract: 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 Pc1 (=Pc2) 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<B to make the effective pressure receiving area (?A) of the high pressure-side valve and the effective pressure receiving area (?B?b) of the low pressure-side valve approximately equal.
    Type: Grant
    Filed: June 3, 2003
    Date of Patent: October 17, 2006
    Assignee: TGK Co., Ltd.
    Inventor: Hisatoshi Hirota
  • Patent number: 7118088
    Abstract: 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.
    Type: Grant
    Filed: April 12, 2005
    Date of Patent: October 10, 2006
    Assignee: TGK Co., Ltd.
    Inventor: Hisatoshi Hirota
  • Patent number: 7117895
    Abstract: The object of the present invention is to provide a switching valve capable of increasing the opening stroke of a valve operated by a differential pressure while saving space, thereby reducing pressure loss. A first valve is disposed between an inlet port and a first outlet port. A pilot valve is provided between a back pressure chamber for a movable plug that holds a valve sheet disposed in a manner opposed to a valve seat, and the first outlet port, such that the first valve is operated by a solenoid. A second valve is arranged between the inlet port and a second outlet port. A back pressure chamber for a movable plug that holds a valve sheet disposed in a manner opposed to a valve seat and the first outlet port are communicated with each other. The second valve is opened by the differential pressure generated by closing of the first valve, and when the first valve is opened, the second valve is closed by the spring since the differential pressure is reduced to zero.
    Type: Grant
    Filed: February 9, 2006
    Date of Patent: October 10, 2006
    Assignee: TGK Co., Ltd.
    Inventor: Katsumi Koyama