Patents by Inventor Keiji Kawahara

Keiji Kawahara 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).

  • Publication number: 20230216364
    Abstract: An object of the present invention is to suppress variations in an angle of a shoulder part of a segment coil to improve easiness in inserting segment coils in a stator core. A stator of an electric motor according to the present invention includes a stator core 12 in which a plurality of slots 12a are formed, and a plurality of segment coils 11 of U shapes inserted respectively in the plurality of slots 12a. The segment coil 11 includes a shoulder part 11a and a shoulder part 11b that are bent to form a U shape. In a front view of the U shape, a press mark 100a is formed on the shoulder part 11a and on the shoulder part 11b, the press mark being a dent sinking in a front-to-rear direction, from a front surface of the shoulder part 11a and from a front surface of the shoulder part 11b. The press mark 100a is formed also on a back surface of the shoulder part 11a and on a back surface of the shoulder part 11b.
    Type: Application
    Filed: February 2, 2021
    Publication date: July 6, 2023
    Applicant: Hitachi Astemo, Ltd.
    Inventors: Keiji KAWAHARA, Masato HIGUMA, Yasuhiko KIMURA, Kenichi NAKAYAMA
  • Publication number: 20200258823
    Abstract: An object of the invention is to improve productivity while suppressing a reduction in a heat radiating performance of a power semiconductor device. According to the invention, there is provided a manufacturing method of a power semiconductor device which includes a conductive member having a first surface and a second surface provided on a side opposite to the first surface and a power semiconductor element which is connected to the conductive member through a bonding material.
    Type: Application
    Filed: July 9, 2018
    Publication date: August 13, 2020
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Takashi KUBOKI, Keiji KAWAHARA, Takeshi KONNO
  • Patent number: 9095924
    Abstract: A welded construction according to the present invention has a first metallic member, on one surface of which a projecting portion is formed and on the other surface of which a depressed portion corresponding to the projecting portion is formed, and a second metallic member are welded together at a welded portion which includes a summit portion of the projecting portion; wherein, on at least one of the first metallic member and the second metallic member, on its opposite surface to its surface that faces the other one of the metallic members, a recessed portion is formed that is recessed from its peripheral region towards a region which corresponds to the welded portion.
    Type: Grant
    Filed: December 15, 2011
    Date of Patent: August 4, 2015
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Shin Onose, Keiji Kawahara, Hiroshi Fujimoto, Kenta Hasegawa
  • Patent number: 9000582
    Abstract: A power semiconductor module includes: a circuit body having a power semiconductor element and a conductor member connected to the power semiconductor element; a case in which the circuit body is housed; and a connecting member which connects the circuit body and the case. The case includes: a first heat dissipating member and a second heat dissipating member which are disposed in opposed relation to each other while interposing the circuit body in between; a side wall which joins the first heat dissipating member and the second heat dissipating member; and an intermediate member which is formed on the periphery of the first heat dissipating member and connected to the side wall, the intermediate member including a curvature that is projected toward a housing space of the case.
    Type: Grant
    Filed: February 21, 2012
    Date of Patent: April 7, 2015
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Shinji Hiramitsu, Atsushi Koshizaka, Masato Higuma, Hiroshi Tokuda, Keiji Kawahara
  • Publication number: 20130328185
    Abstract: A power semiconductor module includes: a circuit body having a power semiconductor element and a conductor member connected to the power semiconductor element; a case in which the circuit body is housed; and a connecting member which connects the circuit body and the case. The case includes: a first heat dissipating member and a second heat dissipating member which are disposed in opposed relation to each other while interposing the circuit body in between; a side wall which joins the first heat dissipating member and the second heat dissipating member; and an intermediate member which is formed on the periphery of the first heat dissipating member and connected to the side wall, the intermediate member including a curvature that is projected toward a housing space of the case.
    Type: Application
    Filed: February 21, 2012
    Publication date: December 12, 2013
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Shinji Hiramitsu, Atsushi Koshizawa, Masato Higuma, Hiroshi Tokuda, Keiji Kawahara
  • Patent number: 8302275
    Abstract: An apparatus for manufacturing an iron core comprising: a plate thickness measurement unit for measuring a thickness of the strip as an intermediate product of the iron core; an inlet guide for positioning the strip in a widthwise direction thereof; a mil roll unit for performing a rolling-bending process to the strip fed out of the inlet guide; a restraint jig for shaping the strip fed out of the mil unit and holding a curvature thereof constant; and a curvature measurement unit for measuring a curvature of the strip to which the rolling-bending process has been performed by using said mill roll. Position control of the inlet guide, the pressure roll unit, and the restraint jig is performed based on at least one of the plate thickness and the curvature of the strip.
    Type: Grant
    Filed: November 20, 2007
    Date of Patent: November 6, 2012
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Atsushi Koshizaka, Toshiaki Ueda, Yuichi Kirihara, Keiji Kawahara, Susumu Sasaki
  • Publication number: 20120156561
    Abstract: A welded construction according to the present invention has a first metallic member, on one surface of which a projecting portion is formed and on the other surface of which a depressed portion corresponding to the projecting portion is formed, and a second metallic member are welded together at a welded portion which includes a summit portion of the projecting portion; wherein, on at least one of the first metallic member and the second metallic member, on its opposite surface to its surface that faces the other one of the metallic members, a recessed portion is formed that is recessed from its peripheral region towards a region which corresponds to the welded portion.
    Type: Application
    Filed: December 15, 2011
    Publication date: June 21, 2012
    Applicants: Hitachi Vehicle Energy, Ltd., Hitachi Automotive Systems, Ltd.
    Inventors: Shin ONOSE, Keiji KAWAHARA, Hiroshi FUJIMOTO, Kenta HASEGAWA
  • Patent number: 8016214
    Abstract: A fuel injection valve comprises a convex portion prominently formed on an outer end surface of a nozzle body, stepped recesses each of which has plural steps formed by press forming on the convex portion, and multi orifices as fuel nozzle holes formed by press forming so that an outlet of each of the orifices is located at a bottom face of each of the stepped recesses. Furthermore, the fuel injection valve has plural sets each of which comprises one of the stepped recesses and the relevant orifice, the orifices incline to each other, and a step on a downstream side in each of the stepped recesses has a larger diameter than a step on an upstream side thereof.
    Type: Grant
    Filed: August 19, 2008
    Date of Patent: September 13, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Masato Higuma, Kenichi Gunji, Keiji Kawahara, Atsushi Sekine
  • Patent number: 7874070
    Abstract: An injection valve has a nozzle body, a valve needle positioned in the nozzle body, an actuator for actuating the valve needle, and an orifice plate fixed at an end of the nozzle body. The orifice plate has a valve seat for cooperating with the valve needle and an orifice for injecting a fluid. The orifice plate is provided with a projection having a convex-curved surface on an orifice outlet side of the orifice plate. A flat surface portion is formed in the area of the convex-curved surface, and the outlet of the orifice is located in the flat surface portion.
    Type: Grant
    Filed: September 12, 2006
    Date of Patent: January 25, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Gunji, Keiji Kawahara, Shuichi Shimizu, Atsushi Sekine, Masafumi Nakano
  • Publication number: 20090242668
    Abstract: A fuel injection valve comprises a convex portion prominently formed on an outer end surface of a nozzle body, stepped recesses each of which has plural steps formed by press forming on the convex portion, and multi orifices as fuel nozzle holes formed by press forming so that an outlet of each of the orifices is located at a bottom face of each of the stepped recesses. Furthermore, the fuel injection valve has plural sets each of which comprises one of the stepped recesses and the relevant orifice, the orifices incline to each other, and a step on a downstream side in each of the stepped recesses has a larger diameter than a step on an upstream side thereof.
    Type: Application
    Filed: August 19, 2008
    Publication date: October 1, 2009
    Applicant: Hitachi, Ltd.
    Inventors: Masato Higuma, Kenichi Gunji, Keiji Kawahara, Atsushi Sekine
  • Publication number: 20080072415
    Abstract: An apparatus for manufacturing an iron core comprising: a plate thickness measurement unit for measuring a thickness of the strip as an intermediate product of the iron core; an inlet guide for positioning the strip in a widthwise direction thereof; a mil roll unit for performing a rolling-bending process to the strip fed out of the inlet guide; a restraint jig for shaping the strip fed out of the mil unit and holding a curvature thereof constant; and a curvature measurement unit for measuring a curvature of the strip to which the rolling-bending process has been performed by using said mill roll. Position control of the inlet guide, the pressure roll unit, and the restraint jig is performed based on at least one of the plate thickness and the curvature of the strip.
    Type: Application
    Filed: November 20, 2007
    Publication date: March 27, 2008
    Applicants: HITACHI, LTD., HITACHI CAR ENGINEERING CO., LTD.
    Inventors: Atsushi KOSHIZAKA, Toshiaki UEDA, Yuichi KIRIHARA, Keiji KAWAHARA, Susumu SASAKI
  • Patent number: 7315104
    Abstract: An apparatus for manufacturing an iron core comprising: a plate thickness measurement unit for measuring a thickness of the strip as an intermediate product of the iron core; an inlet guide for positioning the strip in a widthwise direction thereof; a mil roll unit for performing a rolling-bending process to the strip fed out of the inlet guide; a restraint jig for shaping the strip fed out of the mil unit and holding a curvature thereof constant; and a curvature measurement unit for measuring a curvature of the strip to which the rolling-bending process has been performed by using said mill roll. Position control of the inlet guide, the pressure roll unit, and the restraint jig is performed based on at least one of the plate thickness and the curvature of the strip.
    Type: Grant
    Filed: August 18, 2004
    Date of Patent: January 1, 2008
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Atsushi Koshizaka, Toshiaki Ueda, Yuichi Kirihara, Keiji Kawahara, Susumu Sasaki
  • Publication number: 20070057093
    Abstract: An injection valve has a nozzle body, a valve needle positioned in the nozzle body, an actuator for actuating the valve needle, and an orifice plate fixed at an end of the nozzle body. The orifice plate has a valve seat for cooperate with the valve needle and an orifice for injecting a fluid. The orifice plate is provided with a projection having a convex-curved surface on an orifice outlet side of the orifice plate. A flat surface portion is formed in the area of the convex-curved surface, and the outlet of the orifice is located in the flat surface portion.
    Type: Application
    Filed: September 12, 2006
    Publication date: March 15, 2007
    Applicant: Hitachi, Ltd.
    Inventors: Kenichi Gunji, Keiji Kawahara, Shuichi Shimizu, Atsushi Sekine, Masafumi Nakano
  • Patent number: 6976381
    Abstract: To manufacture a cylindrical member, such as the nozzle body of a fuel injector, in which a fluid passage is formed at high productivity and to improve the reliability. A cylindrical member, such as the nozzle body of a fuel injector, in which a fluid passage is formed is manufactured by drawing martenstic stainless steel. In addition, during the drawing process of martenstic stainless steel, an intermediate product is annealed and lug is removed after another drawing process, and then is subjected to drawing again to obtain a product.
    Type: Grant
    Filed: March 19, 2002
    Date of Patent: December 20, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Koshizaka, Atsushi Sekine, Keiji Kawahara, Mizuho Yokoyama
  • Publication number: 20050061046
    Abstract: An apparatus for manufacturing an iron core comprising: a plate thickness measurement unit for measuring a thickness of the strip as an intermediate product of the iron core; an inlet guide for positioning the strip in a widthwise direction thereof; a mil roll unit for performing a rolling-bending process to the strip fed out of the inlet guide; a restraint jig for shaping the strip fed out of the mil unit and holding a curvature thereof constant; and a curvature measurement unit for measuring a curvature of the strip to which the rolling-bending process has been performed by using said mill roll. Position control of the inlet guide, the pressure roll unit, and the restraint jig is performed based on at least one of the plate thickness and the curvature of the strip.
    Type: Application
    Filed: August 18, 2004
    Publication date: March 24, 2005
    Inventors: Atsushi Koshizaka, Toshiaki Ueda, Yuichi Kirihara, Keiji Kawahara, Susumu Sasaki
  • Publication number: 20050014539
    Abstract: In a high-frequency transceiver apparatus wherein an antenna substrate made of a dielectric material and having an antenna conductor pattern formed thereon is bonded onto one surface of a base plate to transmit and receive a high frequency wave signal, the flatness accuracy of the surface of the antenna substrate is set at ?/20 or less when ? denotes effective wavelength.
    Type: Application
    Filed: October 17, 2003
    Publication date: January 20, 2005
    Inventors: Atsushi Koshizaka, Keiji Kawahara, Kazuo Matsuura
  • Patent number: 6710745
    Abstract: A high-frequency communication apparatus has a case containing a transmitter-receiver including circuit elements. A functional structure capable of confining radiation energy radiated by unnecessary radio wave source to prevent the radiation energy from interfering with the operations of the transmitter-receiver is formed on at least one of the walls of the case by forming a plurality of projections in regular arrangement by press working. The circuit elements of the transmitter-receiver are packed in the case to suppress the undesired electromagnetic coupling of internal and external electromagnetic waves with the circuit elements of the transmitter-receiver.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: March 23, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Koshizaka, Shirou Oouchi, Mizuho Yokoyama, Keiji Kawahara
  • Publication number: 20030122727
    Abstract: A high-frequency communication apparatus has a case containing a transmitter-receiver including circuit elements. A functional structure capable of confining radiation energy radiated by unnecessary radio wave source to prevent the radiation energy from interfering with the operations of the transmitter-receiver is formed on at least one of the walls of the case by forming a plurality of projections in regular arrangement by press working. The circuit elements of the transmitter-receiver are packed in the case to suppress the undesired electromagnetic coupling of internal and external electromagnetic waves with the circuit elements of the transmitter-receiver.
    Type: Application
    Filed: December 17, 2002
    Publication date: July 3, 2003
    Applicant: HITACHI, LTD.
    Inventors: Atsushi Koshizaka, Shirou Oouchi, Mizuho Yokoyama, Keiji Kawahara
  • Patent number: 6580395
    Abstract: A high-frequency communication apparatus has a case containing a transmitter-receiver including circuit elements. A functional structure capable of confining radiation energy radiated by unnecessary radio wave source to prevent the radiation energy from interfering with the operations of the transmitter-receiver is formed on at least one of the walls of the case by forming a plurality of projections in regular arrangement by press working. The circuit elements of the transmitter-receiver are packed in the case to suppress the undesired electromagnetic coupling of internal and external electromagnetic waves with the circuit elements of the transmitter-receiver.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: June 17, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Koshizaka, Shirou Oouchi, Mizuho Yokoyama, Keiji Kawahara
  • Publication number: 20030071147
    Abstract: To manufacture a cylindrical member, such as the nozzle body of a fuel injector, in which a fluid passage is formed at high productivity and to improve the reliability.
    Type: Application
    Filed: March 19, 2002
    Publication date: April 17, 2003
    Inventors: Atsushi Koshizaka, Atsushi Sekine, Keiji Kawahara, Mizuho Yokoyama