Patents by Inventor Hirohisa Yamamura

Hirohisa Yamamura 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).

  • Patent number: 6414867
    Abstract: A heat sink or cooling case has a cooling channel and at least one opening formed to face part of the channel. A first seal is provided outside the at least one opening. A cooling case has a groove located outside the first seal. Holes are discretely formed in the groove and lead from the groove to an exterior of the cooling case. A second seal is provided outside the groove. A radiating plate constituting a circuit case is mounted on the heat sink by using a clamping device inside or outside the second seal.
    Type: Grant
    Filed: February 16, 2001
    Date of Patent: July 2, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Osamu Suzuki, Heikichi Kuwabara, Akio Yasukawa, Mitsuyuki Hombu, Hirohisa Yamamura, Sanshirou Obara, Kaname Sasaki
  • Patent number: 6410978
    Abstract: A semiconductor device in which fatigue failure of a solder layer underneath a semiconductor chip mounted on a base can be prevented from occurring due to repetitions of turn-on and -off of power during operation thereof, is provided, that is, a recess is formed in the base in a part underneath the semiconductor chip so as to prevent occurrence of thermal expansion in the base.
    Type: Grant
    Filed: August 10, 1999
    Date of Patent: June 25, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Akio Yasukawa, Hirohisa Yamamura, Tatsuya Shigemura
  • Publication number: 20020050403
    Abstract: A semiconductor device in which fatigue failure of a solder layer underneath a semiconductor chip mounted on a base can be prevented from occurring due to repetitions of turn-on and -off of power during operation thereof, is provided, that is, a recess is formed in the base in a part underneath the semiconductor chip so as to prevent occurrence of thermal expansion in the base.
    Type: Application
    Filed: August 10, 1999
    Publication date: May 2, 2002
    Inventors: AKIO YASUKAWA, HIROHISA YAMAMURA, TATSUYA SHIGEMURA
  • Publication number: 20010042925
    Abstract: A wire bonding method and apparatus implement the flatly thinner plastic deformation for the joint section of a wire, which has a diameter ranging 100-600 &mgr;m, on its feed side, feed out and position the flatly deformed wire joint section to a target joint surface, and join the wire to it by pressing the positioned wire joint section, with vibration being applied, onto the joint surface with a ultrasonic wire bonder. A high-power semiconductor device fabricated based on this scheme has a long life of wire joints.
    Type: Application
    Filed: July 25, 2001
    Publication date: November 22, 2001
    Inventors: Noriaki Yamamoto, Yukinori Taneda, Hirohisa Yamamura, Akio Yasukawa, Osamu Suzuki, Tatsuya Shigemura
  • Publication number: 20010014029
    Abstract: A heat sink or cooling case has a cooling channel and at least one opening formed to face part of the channel. A first seal is provided outside the at least one opening. A cooling case has a groove located outside the first seal. Holes are discretely formed in the groove and leads from the groove to an exterior of the cooling case. A second seal is provided outside the groove. A radiating plate constituting a circuit case is mounted on the heat sink by using a clamping device inn or outside the second seal.
    Type: Application
    Filed: February 16, 2001
    Publication date: August 16, 2001
    Inventors: Osamu Suzuki, Heikichi Kuwabara, Akio Yasukawa, Mitsuyuki Hombu, Hirohisa Yamamura, Sanshirou Obara, Kaname Sasaki
  • Patent number: 6271601
    Abstract: A wire bonding method and apparatus implement the flatly thinner plastic deformation for the joint section of a wire, which has a diameter ranging 100-600 &mgr;m, on its feed side, feed out and position the flatly deformed wire joint section to a target joint surface, and join the wire to it by pressing the positioned wire joint section, with vibration being applied, onto the joint surface with a ultrasonic wire bonder. A high-power semiconductor device fabricated based on this scheme has a long life of wire joints.
    Type: Grant
    Filed: May 6, 1999
    Date of Patent: August 7, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Noriaki Yamamoto, Yukinori Taneda, Hirohisa Yamamura, Akio Yasukawa, Osamu Suzuki, Tatsuya Shigemura
  • Patent number: 6166937
    Abstract: IGBT modules, bus bars and capacitors in an inverter main circuit are secured on the front face of a heat sink and at the back side of the heat sink a water cooling channel is formed to cool the IGBT modules. The bus bars and the capacitor, thereby the size of an inverter device used in an electric car is reduced and the duration thereof is prolonged.
    Type: Grant
    Filed: May 21, 1999
    Date of Patent: December 26, 2000
    Assignee: Hitachi Ltd.
    Inventors: Hirohisa Yamamura, Osamu Suzuki, Akio Yasukawa, Nobunori Matsudaira
  • Patent number: 6021040
    Abstract: A power storage device such as a capacitor, a battery or the like having a power storage element and a case, and a power converter using the power storage device in combination with an invertor circuit. The power storage device including a capacitor, a battery or the like is constructed of a power storage element having an anode foil, a cathode foil and an insulating material, and a highly thermally conductive and electrically conductive case, where an electrode foil of the power storage element is thermally insulated from the case by an insulating material and is in thermal contact with the case. The power storage device and the invertor circuit are arranged in close proximity and in thermal contact with a cooling unit. With this configuration, it is possible to prevent a leak current from flowing into the case to eliminate the generation of noise, maintain the security, and accomplish a longer effective life, a reduced size and a higher capacitance.
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: February 1, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Osamu Suzuki, Kaname Sasaki, Heikichi Kuwahara, Hirohisa Yamamura
  • Patent number: 5793106
    Abstract: A semiconductor device, suitable for use in an invertor device for large currents in which IGBT chips are used and of which a high reliability is required, has an insulating plate on which are mounted semiconductor chips, a resin case enclosing the semiconductor chips, a filler resin filled into the resin case and covering the semiconductor chips and filling in the space between the semiconductor chips and the resin case, and a heatsink to which the insulating plate is attached, wherein, for purposes of attaching the insulating plate to the heatsink, the resin case is used to press the insulating plate onto the heatsink. Some benefits of this construction are that is makes it possible to eliminate the problem of fatigue failure of a solder layer previously used for attaching the insulating plate to the heatsink by dispensing with that solder layer, while at the same time improving the transfer of heat from the insulating plate to the heatsink, and thereby improving the removal of heat from the device.
    Type: Grant
    Filed: February 28, 1996
    Date of Patent: August 11, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Akio Yasukawa, Hirohisa Yamamura, Shotaro Naito, Heikichi Kuwahara, Osamu Suzuki, Masanori Muso, Nobuo Fujieda
  • Patent number: 5481460
    Abstract: The present invention relates to a controller for an electric vehicle in which right and left drive wheels are respectively driven by drive motors which are individually provided. The controller for an electric vehicle comprises motors for driving right and left wheels, means for detecting rotating speeds or rotation torques of the wheels, and a facility for taking a rotation deviation between output signals from the detection means close to zero. As a result, the vehicle is always operated in safety.
    Type: Grant
    Filed: June 3, 1992
    Date of Patent: January 2, 1996
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Ryoso Masaki, Shigeki Morinaga, Kazuo Tahara, Hirohisa Yamamura, Kenzo Kajiwara, Hiroyuki Yamada, Nobuo Inoue, Toshio Suzuki
  • Patent number: 5345155
    Abstract: An electric vehicle control system, according to the present invention, comprises at least two electric motors for independently driving left and right wheels of the vehicle, power supply unit for supplying power to the motors, unit for detecting command entered by a driver of the vehicle and driving operational amount provided for the vehicle, unit for detecting output torques of the two motors, unit for calculating a motor speed difference command signal for making the two output torques consistent with each other, unit for calculating a vehicle speed command signal for the vehicle on the basis of detected command and the driving operational amount, unit for calculating motor speed command signals for respective of the motors on the basis of calculated motor speed difference command signal and the vehicle speed command signal, unit for detecting actual speeds of the two motors, and control unit for voltage controlling supply power from the power supply unit to the motors so that the detected actual speeds o
    Type: Grant
    Filed: March 25, 1992
    Date of Patent: September 6, 1994
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Ryoso Masaki, Yuusuke Takamoto, Sanshiro Obara, Hirohisa Yamamura, Hiroyuki Yamada
  • Patent number: 5309073
    Abstract: An electric vehicle control device is disclosed, which includes an AC motor for driving a vehicle; a main electric power conversion unit for supplying an AC voltage to the AC motor; a battery for supplying a DC voltage to the main electric power conversion unit; an auxiliary electric power conversion unit connected to the battery and adapted to be connected to a load or a power supply; a controller for controlling the main and auxiliary electric power conversion units so as to act selectively as an inverter or a converter; and a switching unit for giving selectively the AC motor the AC voltage from the main and auxiliary electric power conversion units under control of the controller. In the running mode of the electric vehicle, the controller described above makes the main electric power conversion unit act as an inverter and controls the switching unit so that the AC voltage from the main electric power conversion unit is given to the AC motor.
    Type: Grant
    Filed: October 20, 1992
    Date of Patent: May 3, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Satoru Kaneko, Ryoso Masaki, Sanshiro Obara, Tsutomu Ohmae, Yuusuke Takamoto, Hirohisa Yamamura
  • Patent number: 5304912
    Abstract: A control apparatus for an induction motor and an electric car propelling motor includes an inverter for supplying a driving current to the induction motor on the basis of a predetermined control signal, a rotational speed sensor for detecting a rotational speed of the induction motor, a V/f control circuit responsive to an input speed command signal for producing a control signal for the inverter, a vector control circuit for producing an inverter control signal on the basis of the speed command signal and the rotational speed signal of the rotational speed sensor, an abnormality detecting circuit for detecting abnormality of the rotational speed sensor.
    Type: Grant
    Filed: September 21, 1992
    Date of Patent: April 19, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Kenzo Kajiwara, Hiroshi Hamano, Hirohisa Yamamura, Ryoso Masaki
  • Patent number: 5270578
    Abstract: A system and method for controlling plural load with high reliability, comprising plural control devices for respectively controlling the plural electric loads, plural switches for respectively giving ordering signals to the control devices to control the respective loads, and a monitor circuit for detecting an out of order control device and generating ordering signals for selecting another control device which is not out of order based on the superiority of the other electric load and the ordering signals from the switches which correspond to the other control device to change from the control device which is out of order to the other control device.
    Type: Grant
    Filed: January 7, 1991
    Date of Patent: December 14, 1993
    Assignee: Hitachi, Ltd.
    Inventor: Hirohisa Yamamura
  • Patent number: 4960178
    Abstract: A generator generates two voltage outputs which have different voltage levels. One voltage output from the generator is used for operating a power steering apparatus. Another voltage output from the generator is used for charging a battery which supplies current to other loads.
    Type: Grant
    Filed: September 22, 1988
    Date of Patent: October 2, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Toshimi Abukawa, Toshiaki Okuyama, Kazuo Tahara, Katsuji Marumoto, Toshiyuki Koterazawa, Mitsuyuki Hombu, Tadashi Takahashi, Hisatugu Ishikura, Hirohisa Yamamura, Toru Tatsuzaki, Tsutomu Omae, Shuichi Takamatsu
  • Patent number: 4926960
    Abstract: An electric power steering apparatus for a vehicle comprises a steering shaft, an electric motor operable to generate an auxiliary steering force having a magnitude corresponding to a value of electric current supplied thereto, a steering toque sensor for detecting a steering torque applied to the steering shaft, a vehicle weight sensor for detecting a vehicle weight, and a control device. The control device is constituted to increase and decrease the value of electric current to be supplied to the electric motor in accordance with not only the increase and decrease of the value detected by the steering torque sensor but also the increase and decrease of the value detected by the vehicle weight sensor.
    Type: Grant
    Filed: September 16, 1988
    Date of Patent: May 22, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Hisatugu Ishikura, Kazuo Tahara, Toshimi Abukawa, Katsuji Marumoto, Toshiyuki Koterazaka, Mitsuyuki Hombu, Tadashi Takahashi, Hirohisa Yamamura, Toru Tatsuzaki, Tsutomu Ohmae, Shuichi Takamatsu
  • Patent number: 4874053
    Abstract: A device for detecting a load torque using angle detectors fitted with a certain spacing on a shaft which is rotated by a drive source and on the basis of a relative angular difference of angles detected by the angle detectors. The device includes two rotary drums or discs fitted with a certain spacing on the drive side and load side of the shaft, with a plurality of magnetic poles for generating magnetic signals being formed on the surface thereof, and a magnetic sensor disposed to confront the surface of the rotary drums or discs, with magnetic resistance effect elements which vary in internal resistance in response to the magnetism of the magnetic poles being provided thereon. The amount of torsion created by the load on the load side of the rotary shaft is measured as a phase difference of outputs of the magnetic sensor, and the torque is detected in terms of the angular difference between the magnetic drums or discs.
    Type: Grant
    Filed: June 22, 1988
    Date of Patent: October 17, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Kimura, Shotaro Naito, Kunio Miyashita, Yasuo Noto, Noboru Sugiura, Tadashi Takahashi, Hirohisa Yamamura, Seizi Yamashita, Syooichi Kawamata, Fumio Tajima, Shigeru Horikoshi
  • Patent number: 4865148
    Abstract: A vehicle height control apparatus responsive to power steering operation is disclosed in which a torque signal indicative of the steering torque imparted to the steering wheel by a driver's operation thereof is used for controlling the power steering system and also for controlling the operation of actuators for adjusting damping force of shock absorber provided to each wheel thereby controlling the height of the vehicle.
    Type: Grant
    Filed: August 9, 1988
    Date of Patent: September 12, 1989
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineer Co., Ltd.
    Inventors: Katsuji Marumoto, Kazuo Tahara, Hisatugu Ishikura, Hirohisa Yamamura, Toru Tatsuzaki, Toshimi Abukawa, Toshiyuki Koterazawa, Mitsuyuki Honbu, Tadashi Takahashi, Shuichi Takamatsu, Tsutomu Ohmae
  • Patent number: 4752771
    Abstract: In a color liquid crystal type electronic instrument panel, the quantity of light to be radiated from a background light source is changed in accordance with a color to be displayed. The color liquid crystal type electronic instrument panel is of the type that a plurality of plural-primary-color stripe filters are disposed on each segment of a display element in the longitudinal direction of the segment; a voltage is applied to electrodes corresponding to the stripe filters having a color selected based on the contents to be displayed, and the background light source is positioned at the back of the display element to enable color-displaying. A device for detecting the brightness of outdoor light is further provided in the liquid crystal display type electronic instrument panel, wherein the quantity of light to be radiated from the background light source is changed in accordance with a detected signal by the detecting device.
    Type: Grant
    Filed: August 22, 1985
    Date of Patent: June 21, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Kouzou Katogi, Osamu Igarashi, Keiichi Tokuyama, Hirohisa Yamamura, Seiji Suda
  • Patent number: 4736198
    Abstract: A liquid crystal display panel including transparent electrode pairs confronting each other with liquid crystal substance disposed therebetween. At least one of each electrode pair is split into thin line electrode strips with color filters of several kinds of color being disposed thereon or on corresponding positions on the opposite electrode. The panel produces a display in an arbitrary color through the application of a certain combination of color signals between the electrodes selectively.
    Type: Grant
    Filed: May 28, 1985
    Date of Patent: April 5, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Keiichi Tokuyama, Seiji Suda, Osamu Igarashi, Hirohisa Yamamura, Kouzo Katogi, Hiroshi Ito, Masaru Kugo, Kazuhiko Sato