Patents by Inventor Akira Uchikawa
Akira Uchikawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20100236925Abstract: A gas sensor includes a ceramic structural member. The ceramic structural member includes a base body formed of an insulating material; and a porous ceramic layer formed integrally with the base body. The ceramic layer is formed of an admixture obtained by mixing a plurality of ceramic materials with each other. The plurality of ceramic materials have grain size distributions different from each other.Type: ApplicationFiled: March 9, 2010Publication date: September 23, 2010Inventors: Akira UCHIKAWA, Masami Kawashima, Shoichi Sakai, Masao Tsukada, Keiji Mori, Kousaku Morita
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Patent number: 7704358Abstract: An oxygen sensor includes a base body portion; and a plurality of function layers laminated on a surface of the base body portion. The function layers includes a solid electrolyte layer adapted to conduct oxygen ions; a reference electrode layer located on a base body portion side of the solid electrolyte layer; a sensing electrode layer located on the opposite side of the solid electrolyte layer to the reference electrode layer; a heater portion adapted to activate the solid electrolyte layer by heating; and a gas diffusion layer formed between the reference electrode layer and the base body portion, and adapted to diffuse a reference gas within the gas diffusion layer. The gas diffusion layer is formed to have a porosity indicating a limit current value ranging between 60 ?A and 200 ?A.Type: GrantFiled: February 28, 2007Date of Patent: April 27, 2010Assignee: Hitachi, Ltd.Inventors: Futoshi Ichiyanagi, Akira Uchikawa, Shoichi Sakai, Goji Matsumoto
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Publication number: 20090312938Abstract: The invention provides an air-fuel ratio control system in which high precision can be applied to the air-fuel ratio feedback control of an engine by using a gas sensor mainly configured by an oxygen sensor that prevents the deterioration of the holding power of sealing material which enables high density filling with a small compressive load or the deterioration of the sealing material. The gas sensor such as the oxygen sensor is based upon a gas content detecting sensor that includes a gas content detecting element and a holder holding the gas content detecting element and that seals a measuring part of the gas content detecting element in the holder by a sealing part in which the sealing material is compressively filled, and has a characteristic that the sealing material is molded by mixed powder including plural species of forms of particles.Type: ApplicationFiled: June 10, 2009Publication date: December 17, 2009Applicant: Hitachi, Ltd.Inventors: Kousaku Morita, Akira Uchikawa, Masami Kawashima, Shoichi Sakai, Masao Tsukada, Keiji Mori, Shosaku Ishihara, Tsuyoshi Fujita
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Publication number: 20080116071Abstract: This device is a degradation judging device for an oxygen sensor having a reference electrode 23 and a measuring electrode 22, both of which hold a solid electrolyte layer therebetween, and measuring oxygen concentrations based on an electromotive force that occurs in accordance with a difference between an oxygen partial pressure of the reference electrode 23 and an oxygen partial pressure of the measuring electrode 22. A control unit 10, which controls operations of intake and exhaust valves, a spark plug and a fuel injection valve, has a degradation judging means that detects an internal resistance value “R1” of the solid electrolyte layer 21 by applying a high-frequency alternating current between the reference electrode 23 and the measuring electrode 22, and judges degradation of the solid electrolyte layer 21 by comparing an average value of the detected internal resistance value “R1” with a reference value.Type: ApplicationFiled: January 11, 2006Publication date: May 22, 2008Inventors: Motonori Nakamura, Akira Uchikawa
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Patent number: 7370545Abstract: An oxygen sensor includes a sensing element detecting an oxygen concentration in a measurement gas that flows in a pipe, a cylindrical protector which covers an outside of the sensing element and whose top end portion projects toward an inside of the pipe. An outside diameter D of the protector and a projection amount L of the protector inside the pipe are set so that a ratio of the product of the outside diameter D and the projection amount L (D×L) to a cross-sectional area S of a flow passage of the pipe becomes substantially smaller than or equal to 2.5%.Type: GrantFiled: October 18, 2006Date of Patent: May 13, 2008Assignee: Hitachi, Ltd.Inventors: Akira Uchikawa, Futoshi Ichiyanagi, Masao Tsukada
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Patent number: 7302828Abstract: An oxygen sensor includes a tubular casing; an oxygen detecting element installed in a leading end of the tubular casing; lead wires each extending from the oxygen detecting element to the outside of the tubular casing through an open base end of the tubular casing, each lead wire including a core wire of metal; a rubber bush plugged in the open base end of the tubular casing, the rubber bush having the lead wires passed therethrough; and a heat resisting structure for protecting the rubber bush from a high temperature. The heat resisting structure is constructed to satisfy the following inequality: 10%?Al/Ar?50%, wherein: Al: The sectional area in total of the lead wires; and Ar: The sectional area of the rubber bush.Type: GrantFiled: September 16, 2005Date of Patent: December 4, 2007Assignee: Hitachi, Ltd.Inventors: Akira Uchikawa, Masao Tsukada, Shoichi Sakai, Masami Kawashima, Keiji Mori
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Publication number: 20070215471Abstract: An exhaust gas sensor has a sensing element having a sensing area that detects certain components in exhaust gas, a holder that supports a base end portion of the sensing element and has a sensor-mounting structure for sensor installation, and a protector that is fixed to the holder and protects the sensing area of the sensing element. To support the sensing element, a sensing element insertion hole for receiving the base end portion of the sensing element is formed at the holder. Then, a clearance between an inner surface of the sensing element insertion hole and a surface of the sensing area is set to be smaller than a clearance between an inner surface of the protector and the surface of the sensing area.Type: ApplicationFiled: March 15, 2007Publication date: September 20, 2007Inventors: Shoichi Sakai, Akira Uchikawa, Masao Tsukada
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Publication number: 20070199820Abstract: An oxygen sensor includes a base body portion; and a plurality of function layers laminated on a surface of the base body portion. The function layers includes a solid electrolyte layer adapted to conduct oxygen ions; a reference electrode layer located on a base body portion side of the solid electrolyte layer; a sensing electrode layer located on the opposite side of the solid electrolyte layer to the reference electrode layer; a heater portion adapted to activate the solid electrolyte layer by heating; and a gas diffusion layer formed between the reference electrode layer and the base body portion, and adapted to diffuse a reference gas within the gas diffusion layer. The gas diffusion layer is formed to have a porosity indicating a limit current value ranging between 60 ?A and 200 ?A.Type: ApplicationFiled: February 28, 2007Publication date: August 30, 2007Applicant: HITACHI, LTD.Inventors: Futoshi Ichiyanagi, Akira Uchikawa, Shoichi Sakai, Goji Matsumoto
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Publication number: 20070108051Abstract: In an oxygen sensor, a basic body is provided and a plurality of function layers are laminated on a surface of the basic body, the function layers including at least a solid electrolyte layer having an oxygen ion conductivity and a pair of electrode layers between which the solid electrolyte layer is inserted, a firing being carried out after the function layers are laminated on the surface of the basic body and, during the firing, a sintering of the basic body and the function layers being sequentially progressed toward an outer surface of the function layers from the basic body.Type: ApplicationFiled: November 16, 2006Publication date: May 17, 2007Inventors: Futoshi Ichiyanagi, Keiji Mori, Masami Kawashima, Akira Uchikawa, Shoichi Sakai, Masao Tsukada
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Publication number: 20070089482Abstract: An oxygen sensor includes a sensing element detecting an oxygen concentration in a measurement gas that flows in a pipe, a cylindrical protector which covers an outside of the sensing element and whose top end portion projects toward an inside of the pipe. An outside diameter D of the protector and a projection amount L of the protector inside the pipe are set so that a ratio of the product of the outside diameter D and the projection amount L (D×L) to a cross-sectional area S of a flow passage of the pipe becomes substantially smaller than or equal to 2.5%.Type: ApplicationFiled: October 18, 2006Publication date: April 26, 2007Inventors: Akira Uchikawa, Futoshi Ichiyanagi, Masao Tsukada
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Publication number: 20070084725Abstract: An oxygen sensor including an oxygen concentration sensing unit including a pair of electrodes and a solid electrolyte layer which is disposed between the pair of electrodes and has an oxygen ion conductivity. A porous protective coat is disposed on an outer surface of the oxygen concentration sensing unit. A protector covers the oxygen concentration sensing unit via a space between the protector and the porous protective coat and has a plurality of inlet holes through which a gas to be measured is introduced into the space. A ratio of a thickness of the porous protective coat to a diameter of each of the plurality of inlet holes is in a range of from 5% to 50%.Type: ApplicationFiled: October 16, 2006Publication date: April 19, 2007Inventors: Shoichi Sakai, Keiji Mori, Futoshi Ichiyanagi, Akira Uchikawa, Masami Kawashima, Masao Tsukada
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Publication number: 20060272944Abstract: An oxygen sensor includes a generally cylindrical casing. A detecting section is disposed at an axially one end side of the casing so as to detect a concentration of oxygen. Lead wires are electrically connected with the detecting section and outwardly extend through an axially other end side of the casing. A seal member is disposed inside an end section located at the axially other end side of the casing. The lead wires pierce the seal member. An insertion section is located at the axially one end side of the casing so that the detecting section projects over the insertion section. The insertion section is inserted into a through-hole formed in a wall of an exhaust pipe, so as to install the oxygen sensor to the exhaust pipe in a condition where the detecting section projects into the exhaust pipe.Type: ApplicationFiled: June 6, 2006Publication date: December 7, 2006Inventors: Futoshi Ichiyanagi, Akira Uchikawa, Masao Tsukada
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Publication number: 20060086175Abstract: An oxygen sensor comprises a tubular casing; an oxygen detecting element installed in a leading end of the tubular casing; lead wires each extending from the oxygen detecting element to the outside of the tubular casing through an open base end of the tubular casing, each lead wire including a core wire of metal; a rubber bush plugged in the open base end of the tubular casing, the rubber bush having the lead wires passed therethrough; and a heat resisting structure for protecting the rubber bush from a high temperature. The heat resisting structure is constructed to satisfy the following inequality: 10%?Al/Ar?50% wherein: Al: The sectional area in total of the lead wires. Ar: The sectional area of the rubber bush.Type: ApplicationFiled: September 16, 2005Publication date: April 27, 2006Inventors: Akira Uchikawa, Masao Tsukada, Shoichi Sakai, Masami Kawashima, Keiji Mori
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Patent number: 6953080Abstract: A first pipe 231 and a second pipe 232 are connected using connectors 233 and 234 so that at least one of the connectors 233 and 234 is located in a through-hole 133. In this way, since the through-hole 133 is filled in by at least one of the connectors 233 and 234, the gap between the connectors 233 and 234 and the edge of the through-hole 133 can be considerably reduced. It is, therefore, possible to prevent hot air from moving to the front of a panel 100 through the gap between connectors 233 and 234 and the edge of the through-hole 133.Type: GrantFiled: September 16, 2002Date of Patent: October 11, 2005Assignee: Denso CorporationInventors: Norihisa Sasano, Akira Uchikawa, Satoshi Matsuura, Kouichi Mizukami
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Patent number: 6595272Abstract: In a double heat exchanger having a condenser core and a radiator core, a protrusion is provided on a condenser header tank which contacts a radiator header tank so that a clearance between the condenser header tank and the radiator header tank around the protrusion is in a range of 0.5 mm-1.5 mm. Further, a coating-removing restriction material such as magnesium for restricting the removal of an oxidation coating formed on the surface of a brazing material is added to one of the contact areas of the protrusion and the contact area of the condenser header tank. Thus, it can prevent brazing material from being collected in the contact areas of the protrusion and the condenser header tank by a capillary phenomenon during brazing. Accordingly, the heat-transmitting area between the radiator header tank and the condenser header tank is not increased, and the heat-radiating capacity of the condenser core is increased.Type: GrantFiled: September 21, 2000Date of Patent: July 22, 2003Assignee: Denso CorporationInventors: Akira Uchikawa, Norihisa Sasano, Satomi Muto, Takaaki Sakane
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Publication number: 20030051858Abstract: A first pipe 231 and a second pipe 232 are connected so that at least one of connectors 233 and 234 is located in a through-hole 133, in a state in which both the connectors 233 and 234 are connected. In this way, since the through-hole 133 is brought to a state of being filled in by the connector 233, the gap between a refrigerant pipe 230 and the edge of the through-hole 133 can be considerably reduced. It is, therefore, possible to prevent hot air from moving to the front side of a vehicle, in front of a panel 100 through the gap between the refrigerant pipe 230 and the edge of the through-hole 133 without the necessity of filling in the gap with a filling means such as rubber (a grommet) and packing.Type: ApplicationFiled: September 16, 2002Publication date: March 20, 2003Inventors: Norihisa Sasano, Akira Uchikawa, Satoshi Matsuura, Kouichi Mizukami
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Patent number: 6523605Abstract: There is disclosed a heat exchanger made of an aluminum alloy having a radiator part (10) and an oil cooler part (11) in combination and manufactured integrally by the brazing method, wherein a refrigerant tank (13) for covering and sealing the oil cooler part is made of an aluminum alloy, an aluminum alloy containing Si in an amount from more than 7.0 wt % to 12.0 wt %, Fe in an amount from more than 0.05 wt % to 0.5 wt %, Cu in an amount from more than 0.4 wt % to 8.0 wt %, Zn in an amount from more than 0.5 wt % to 10.0 wt %, and the balance of aluminum and inevitable impurities is used as a filler material of brazing sheets that are used for the oil cooler part and are brazed in the tank, and the refrigerant tank is assembled integrally with the radiator part and the oil cooler part by brazing with the brazing material.Type: GrantFiled: March 12, 2001Date of Patent: February 25, 2003Assignees: The Furukawa Electric Co., Ltd., Denso CorporationInventors: Takeyoshi Doko, Koji Okada, Takeshi Iguchi, Takaaki Sakane, Yoshihiro Kinoshita, Taketoshi Toyama, Akira Uchikawa, Satoshi Nohira, Homare Koutate
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Patent number: 6523603Abstract: In a double heat exchanger with a condenser and a radiator, a flexible portion formed into a wave shape to be flexible is provided in a side plate at least at one side of connection portions of the side plate, connected to condenser header tanks and radiator header tanks. Further, a slit is provided to be recessed from one longitudinal end of the side plate to the flexible portion. Accordingly, a heat stress generated in condenser tubes and radiator tubes can be absorbed by the flexible portion even when a length of the slit is made shorter.Type: GrantFiled: August 27, 2001Date of Patent: February 25, 2003Assignee: Denso CorporationInventors: Akira Uchikawa, Shinobu Suzuki, Satomi Muto
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Patent number: 6357521Abstract: A radiator has plural metal tubes and a metal header tank. The header tank has plural connection portions each of which is connected to each of the tubes, and plural reinforcement ribs formed opposite the connection portions at a non-connection portion of the header tank to which no tube is connected. The reinforcement ribs and the connection portions are arranged in a longitudinal direction of the header tank at substantially the same pitch, so that each of the reinforcement ribs is disposed opposite each of the connection portions. Therefore, a rigidity of the non-connection portion is increased by the reinforcement ribs, and an internal pressure of the header tank is restricted from being intensively applied to the non-connection portion. As a result, a mechanical strength of the header tank is sufficiently increased without increasing a thickness of a metal plate from which the header tank is formed.Type: GrantFiled: March 24, 2000Date of Patent: March 19, 2002Assignee: Denso CorporationInventors: Tatsuo Sugimoto, Norihisa Sasano, Satomi Muto, Takaaki Sakane, Akira Uchikawa
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Publication number: 20020023735Abstract: In a double heat exchanger with a condenser and a radiator, a flexible portion formed into a wave shape to be flexible is provided in a side plate at least at one side of connection portions of the side plate, connected to condenser header tanks and radiator header tanks. Further, a slit is provided to be recessed from one longitudinal end of the side plate to the flexible portion. Accordingly, a heat stress generated in condenser tubes and radiator tubes can be absorbed by the flexible portion even when a length of the slit is made shorter.Type: ApplicationFiled: August 27, 2001Publication date: February 28, 2002Inventors: Akira Uchikawa, Shinobu Suzuki, Satomi Muto