Patents by Inventor Tomoya Yamakawa
Tomoya Yamakawa 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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Patent number: 6886402Abstract: Gas temperature detection wiring is provided with a first wiring portion disposed parallel to and in close proximity to a flow rate detector portion for a length substantially equivalent to a length of the flow rate detector portion; and a second wiring portion disposed so as to extend from the first wiring portion to an end portion of a pectinate pattern of a gas temperature detector portion. The gas temperature detection wiring is formed so as to connect electrode terminals and the gas temperature detector portion. A high-thermal-resistance portion having increased thermal resistance is constructed by reducing a width of a portion of the second wiring portion.Type: GrantFiled: July 2, 2003Date of Patent: May 3, 2005Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Masao Kikuchi, Tomoya Yamakawa
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Patent number: 6871534Abstract: A post in a fluid passage for passing a fluid flow extends across a part of the fluid flow; a measuring duct in the post extends through the post; and a flow rate detector is located in the measuring duct. The measuring duct has a fluid introduction port with an elongated shape, the measuring duct is constricted and has at least a portion located between the fluid introduction port and the flow rate detector, substantially smoothly narrowing toward a downstream direction of the flow in a longitudinal direction of the elongated shape.Type: GrantFiled: October 22, 1999Date of Patent: March 29, 2005Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Shingo Hamada, Fumiyoshi Yonezawa, Hiroyuki Uramachi, Tomoya Yamakawa, Takeharu Oshima, Satoru Kotoh
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Patent number: 6868722Abstract: A diversion passage is constructed into an inverted U shape in which an upstream diversion passage and a downstream diversion passage each having a passage direction in a direction of projection of a detector flow tube communicate by means of a curved portion. An inflow port is constructed by removing a portion of a wall of the upstream diversion passage on an upstream side in the main direction of flow, and removing a portion of first and second side walls of the upstream diversion passage facing each other in a direction perpendicular to the main direction of flow and the direction of projection of the detector flow tube. In addition, a wall surface on a downstream side of the upstream diversion passage in the main direction of flow at the inflow port is formed into a curved surface shape that is gradually displaced upstream relative to the direction of projection of the detector flow tube to constitute an air lead-in surface.Type: GrantFiled: February 9, 2004Date of Patent: March 22, 2005Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Koji Tanimoto, Hiroyuki Uramachi, Tomoya Yamakawa, Shingo Hamada
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Publication number: 20040226357Abstract: A diversion passage is constructed into an inverted U shape in which an upstream diversion passage and a downstream diversion passage each having a passage direction in a direction of projection of a detector flow tube communicate by means of a curved portion. An inflow port is constructed by removing a portion of a wall of the upstream diversion passage on an upstream side in the main direction of flow, and removing a portion of first and second side walls of the upstream diversion passage facing each other in a direction perpendicular to the main direction of flow and the direction of projection of the detector flow tube. In addition, a wall surface on a downstream side of the upstream diversion passage in the main direction of flow at the inflow port is formed into a curved surface shape that is gradually displaced upstream relative to the direction of projection of the detector flow tube to constitute an air lead-in surface.Type: ApplicationFiled: February 9, 2004Publication date: November 18, 2004Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Koji Tanimoto, Hiroyuki Uramachi, Tomoya Yamakawa, Shingo Hamada
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Patent number: 6729182Abstract: In a flow rate sensor, a sensing passage, into which a fluid is introduced and in which a flow rate sensing element is disposed, a support member for supporting the sensing passage, and a circuit case, in which an electronic circuit unit for controlling the flow rate sensing element is accommodated, are formed integrally with each other, and the support member extends into a main passage through a hole opened to the main passage so as to position the sensing passage in the main passage. A structural member, the outside shape of which is formed to have a fluid resistance approximately similar to that of the portion of the support member extending from the hole, is disposed at a position approximately symmetrical with the portion of the support member extending from the hole about the sensing passage.Type: GrantFiled: December 12, 2002Date of Patent: May 4, 2004Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Hiroyuki Uramachi, Fumiyoshi Yonezawa, Tomoya Yamakawa
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Patent number: 6725716Abstract: A thermo-sensitive flow rate sensor having a flow rate detecting device comprising: a plate-like substrate; a heating element and a temperature compensating element constituted by thermo-sensitive resistance films and formed on a top surface of the substrate in such a way as to be spaced apart from each other; and a low heat capacity portion formed by removing partially an area, in which the heating element is formed, of the substrate from a back surface side thereof. This thermo-sensitive flow rate sensor is used for measuring the flow velocity or flow rate of a measurement fluid according to a heat transfer phenomenon where a heat is transferred from the heating element or from a portion heated by the heating element to the measurement fluid.Type: GrantFiled: October 8, 1999Date of Patent: April 27, 2004Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Masahiro Kawai, Tomoya Yamakawa, Akira Yamashita, Yuuichi Sakai
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Publication number: 20040055377Abstract: Gas temperature detection wiring is provided with a first wiring portion disposed parallel to and in close proximity to a flow rate detector portion for a length substantially equivalent to a length of the flow rate detector portion; and a second wiring portion disposed so as to extend from the first wiring portion to an end portion of a pectinate pattern of a gas temperature detector portion. The gas temperature detection wiring is formed so as to connect electrode terminals and the gas temperature detector portion. A high-thermal-resistance portion having increased thermal resistance is constructed by reducing a width of a portion of the second wiring portion.Type: ApplicationFiled: July 2, 2003Publication date: March 25, 2004Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Masao Kikuchi, Tomoya Yamakawa
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Patent number: 6684693Abstract: A heat generation type flow sensor of an enhanced output sensitivity which is destined for use, for example, as an air flow sensor employed in an engine control system of a motor vehicle.Type: GrantFiled: November 29, 2000Date of Patent: February 3, 2004Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Kouji Tanimoto, Tomoya Yamakawa, Yuji Ariyoshi
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Patent number: 6679114Abstract: A thermosensitive flow rate sensor includes a detecting element, in which a heating element and a fluid temperature detector are formed so as to be separated from each other on a surface of a flat substrate and a flow rate detection diaphragm is formed under a region where the heating element is formed, and a support having a recess portion, the detecting element being housed inside the recess portion such that a surface of the detecting element is positioned generally in a common plane with a surface of the support and such that a direction of alignment of the heating element and the fluid temperature detector is perpendicular to a direction of flow of a fluid being measured, and a groove being formed in the support so as to pass under a region where the fluid temperature detector is formed in the direction of flow of the fluid being measured.Type: GrantFiled: April 15, 2002Date of Patent: January 20, 2004Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Tomoya Yamakawa
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Patent number: 6675644Abstract: A thermo-sensitive flow rate sensor that comprises a plate-like substrate, a part of which is removed so that a space is provided therein, a diaphragm portion formed like a thin layer above the space in such a manner as to be integral with the plate-like substrate, and a heating element constituted by a thermo-sensitive electrically resistant film formed on the diaphragm. Plural holes penetrating the diaphragm portion are bored in an outer peripheral portion of the heating element. Each of the plurality of holes is shaped in such a way as to have obtuse corner portions or to have substantially no corner portions. The thermo-sensitive flow rate sensor measures the flow rate of a fluid, which is to be measured, according to an amount of heat transferred to the fluid from a part heated by energizing the heating element.Type: GrantFiled: April 12, 1999Date of Patent: January 13, 2004Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Tomoya Yamakawa, Masahiro Kawai, Yutaka Ohashi, Yuichi Sakai, Akira Yamashita, Kazuhiko Tsutsumi
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Patent number: 6615655Abstract: A flow rate detecting element measuring the flow rates of various fluids, particularly the intake air of an internal combustion engine. The flow rate detecting element has a thin film layer including a support film and a protective film on one surface of a flat substrate, a heating resistance section and a comparative resistance section thermosensitive resistor having patterns and located between the support film and the protective film. The flat substrate has a recess which penetrates the flat substrate in the thickness direction thereof and facing the heating resistance section and the comparative resistance section. A fluid flow passage communicates with the recess which faces the comparative resistance section for fluid flow into the recess. Flow rate or velocity of a fluid can be measured accurately using the heating resistance section according to the fluid temperature reported by the comparative resistance section.Type: GrantFiled: January 17, 2002Date of Patent: September 9, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Yuichi Sakai, Akira Yamashita, Motohisa Taguchi, Tomoya Yamakawa, Masahiro Kawai, Kazuhiko Tsutsumi
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Publication number: 20030101810Abstract: In a flow rate sensor, a sensing passage, into which a fluid is introduced and in which a flow rate sensing element is disposed, a support member for supporting the sensing passage, and a circuit case, in which an electronic circuit unit for controlling the flow rate sensing element is accommodated, are formed integrally with each other, and the support member extends into a main passage through a hole opened to the main passage so as to position the sensing passage in the main passage. A structural member, the outside shape of which is formed to have a fluid resistance approximately similar to that of the portion of the support member extending from the hole, is disposed at a position approximately symmetrical with the portion of the support member extending from the hole about the sensing passage.Type: ApplicationFiled: December 12, 2002Publication date: June 5, 2003Inventors: Hiroyuki Uramachi, Fumiyoshi Yonezawa, Tomoya Yamakawa
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Patent number: 6561021Abstract: A flow rate-measuring device capable of measuring accurately a flow rate of fluid to be measured containing a drift or eddy as compared with a conventional device is provided. A flow rate-measuring passage 11 for measuring a flow rate of the fluid to be measured is constructed so that its opening area in an upstream region communicating to an inlet 111 gradually decreases from upstream to downstream. A flow rate-detecting element 31 is disposed near an outlet in the flow rate-measuring passage 11. The device is provided with a leak flow passage 18 allowing a part of the fluid which has flown in from the inlet 111 of the flow rate-measuring passage 11 to leak out of the flow rate-measuring passage 11 at a portion upstream from an outlet 112 of the flow rate-measuring passage 11, in particular upstream from a position where the flow rate-detecting element 31 is disposed.Type: GrantFiled: April 23, 2001Date of Patent: May 13, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Hiroyuki Uramachi, Fumiyoshi Yonezawa, Naruki Suetake, Ryuji Tohyama, Tomoya Yamakawa, Shingo Hamada, Takeharu Oshima
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Patent number: 6557410Abstract: In a flow rate sensor, a sensing passage, into which a fluid is introduced and in which a flow rate sensing element is disposed, a support member for supporting the sensing passage, and a circuit case, in which an electronic circuit unit for controlling the flow rate sensing element is accommodated, are formed integrally with each other, and the support member extends into a main passage through a hole opened to the main passage so as to position the sensing passage in the main passage. A structural member, the outside shape of which is formed to have a fluid resistance approximately similar to that of the portion of the support member extending from the hole, is disposed at a position approximately symmetrical with the portion of the support member extending from the hole about the sensing passage.Type: GrantFiled: November 26, 2001Date of Patent: May 6, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Hiroyuki Uramachi, Fumiyoshi Yonezawa, Tomoya Yamakawa
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Patent number: 6539793Abstract: The invention provides a flow rate detector capable of precisely detecting a flow rate of an object fluid and effectively reducing a leaning error even when the object fluid is pulsating, thereby improving precision in detection of flow rate. The flow rate detector comprises a flow detector 50 for outputting a flow-detecting signal Sf according to a flow rate of the object fluid utilizing heat transfer phenomenon from an exothermic resistor 12 disposed in a fluid passage to the object fluid, and a gain compensator 60 for compensating an error in a flow-detecting signal Sf by amplifying the flow-detecting signal Sf from the flow detector 50, wherein the gain compensator 60 is arranged to amplify the flow-detecting signal Sf by a substantially constant alternating current gain G3 larger than a direct current gain G1 at the time of zero frequency, in a frequency range higher than a frequency f2A corresponding to the minimum pulsating frequency of the object fluid.Type: GrantFiled: October 24, 2001Date of Patent: April 1, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Koji Tanimoto, Shinji Taniguchi, Tomoya Yamakawa, Ryuji Toyama
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Patent number: 6513375Abstract: In a flow rate sensor, a sensing passage, into which a fluid is introduced and in which a flow rate sensing element is disposed, a support member for supporting the sensing passage, and a circuit case, in which an electronic circuit unit for controlling the flow rate sensing element is accommodated, are formed integrally with each other, and the support member extends into a main passage through a hole opened to the main passage so as to position the sensing passage in the main passage. A structural member, the outside shape of which is formed to have a fluid resistance approximately similar to that of the portion of the support member extending from the hole, is disposed at a position approximately symmetrical with the portion of the support member extending from the hole about the sensing passage.Type: GrantFiled: November 26, 2001Date of Patent: February 4, 2003Assignee: Mitsubishi Denki Kabushili KaishaInventors: Hiroyuki Uramachi, Fumiyoshi Yonezawa, Tomoya Yamakawa
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Publication number: 20020174718Abstract: A thermosensitive flow rate sensor includes a detecting element, in which a heating element and a fluid temperature detector are formed so as to be separated from each other on a surface of a flat substrate and a flow rate detection diaphragm is formed under a region where the heating element is formed, and a support having a recess portion, the detecting element being housed inside the recess portion such that a surface of the detecting element is positioned generally in a common plane with a surface of the support and such that a direction of alignment of the heating element and the fluid temperature detector is perpendicular to a direction of flow of a fluid being measured, and a groove being formed in the support so as to pass under a region where the fluid temperature detector is formed in the direction of flow of the fluid being measured.Type: ApplicationFiled: April 15, 2002Publication date: November 28, 2002Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventor: Tomoya Yamakawa
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Publication number: 20020170352Abstract: The invention provides a flow rate detector capable of precisely detecting a flow rate of an object fluid and effectively reducing a leaning error even when the object fluid is pulsating, thereby improving precision in detection of flow rate. The flow rate detector comprises a flow detector 50 for outputting a flow-detecting signal Sf according to a flow rate of the object fluid utilizing heat transfer phenomenon from an exothermic resistor 12 disposed in a fluid passage to the object fluid, and a gain compensator 60 for compensating an error in a flow-detecting signal Sf by amplifying the flow-detecting signal Sf from the flow detector 50, wherein the gain compensator 60 is arranged to amplify the flow-detecting signal Sf by a substantially constant alternating current gain G3 larger than a direct current gain G1 at the time of zero frequency, in a frequency range higher than a frequency f2A corresponding to the minimum pulsating frequency of the object fluid.Type: ApplicationFiled: October 24, 2001Publication date: November 21, 2002Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Koji Tanimoto, Shinji Taniguchi, Tomoya Yamakawa, Ryuji Toyama
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Patent number: 6470742Abstract: To obtain a flow sensor having excellent responsibility, sensitivity and reliability and high flow detection accuracy by suppressing the deformation of a diaphragm, first additional patterns are formed on a side opposite to connection patterns of a heating element so that thin film patterns formed on the diaphragm become almost symmetrical, thereby suppressing the deformation of the diaphragm caused by internal stress between a base film or protective film and a platinum film forming the thin film patterns and the differences of mechanical or thermal properties therebetween.Type: GrantFiled: July 26, 1999Date of Patent: October 29, 2002Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Tomoya Yamakawa, Motohisa Taguchi
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Publication number: 20020073773Abstract: In a flow rate sensor, a sensing passage, into which a fluid is introduced and in which a flow rate sensing element is disposed, a support member for supporting the sensing passage, and a circuit case, in which an electronic circuit unit for controlling the flow rate sensing element is accommodated, are formed integrally with each other, and the support member extends into a main passage through a hole opened to the main passage so as to position the sensing passage in the main passage. A structural member, the outside shape of which is formed to have a fluid resistance approximately similar to that of the portion of the support member extending from the hole, is disposed at a position approximately symmetrical with the portion of the support member extending from the hole about the sensing passage.Type: ApplicationFiled: November 26, 2001Publication date: June 20, 2002Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Hiroyuki Uramachi, Fumiyoshi Yonezawa, Tomoya Yamakawa