Patents by Inventor Heikichi Kuwahara

Heikichi Kuwahara 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: 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: 5925929
    Abstract: A cooling apparatus for electronic device comprises an electronic element unit which comprises a base member, a thermal conductive electric insulating layer soldered to the base member and a plurality of electronic elements soldered to the thermal conductive electric insulating layer at least one cooling unit which is detachably kept in pressure contact with the base member of the electronic element unit and comprises a cooling block, at least one heat pipe having a refrigerant sealingly contained therein and inserted in the cooling block at one end thereof and a plurality of radiation fins provided at the other end of the at least one heat pipe; and a device which serves to detachably keep the electronic element unit and the cooling unit in pressure contact with each other. The other end of the heat pipe extends obliquely with a predetermined angle (.alpha.) with respect to the inserted portion thereof.
    Type: Grant
    Filed: October 28, 1996
    Date of Patent: July 20, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Heikichi Kuwahara, Kazumasa Fujioka, Toshio Takasaki, Syuuji Saitoo, Eiichi Toyota
  • Patent number: 5925947
    Abstract: An interior cooling air flow is moved by an interior fan through an inside ventilation passage provided on an inside surface of a stator frame of a totally-enclosed type motor. An exterior cooling air produced by an exterior fan is passed through an outside surface of ventilation passage provided on an outside the stator frame. An inner heat radiation rib is provided in the axial direction on an inner face the inside ventilation passage so that the temperature rise of the motor can be reduced by an improvement in the cooling characteristic. In this way, a compact size totally-enclosed type motor having an improved cooling characteristic is obtained.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: July 20, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Kenzo Kajiwara, Kouki Nagai, Kenji Takahashi, Heikichi Kuwahara
  • 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: 5793611
    Abstract: An electronic device comprises a substrate having electronic parts, electric conductive wires for electrically connecting between the electronic parts, a front surface on which the electronic parts and electric conductive wires are mounted, a reverse surface and at least one electronic part back portion opposite to the electronic parts; and at least one high thermal conductivity member, a thermal conductivity coefficient thereof being higher than that of the substrate, the high thermal conductivity member being connected to the electronic part back portion while the high thermal conductivity member is opposite to the electronic parts in a substrate width direction to decrease a difference in temperature between the electronic parts.
    Type: Grant
    Filed: November 19, 1996
    Date of Patent: August 11, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Norio Nakazato, Shigeki Hirasawa, Shoji Masukawa, Heikichi Kuwahara
  • Patent number: 5651414
    Abstract: A cooling apparatus having a plurality of heat pipes is improved to reduce the condensation capacity of selected heat pipes when ambient air temperature is low, so as to facilitate start-up of the cooling apparatus from a state in which the working fluid in the heat pipes has been frozen. The cooling apparatus has a block of a high heat conductivity in which one end of each heat pipe serving as an evaporation section of the heat pipe is embedded. Heat radiation fins are attached to portions of the heat pipes exposed from the block, so that the exposed portions of the heat pipes serve as condensation sections of the respective heat pipes. There are two types of heat radiation fins: a first type of fins which are attached to all the heat pipes and a second type of fins which are attached only to selected heat pipes.
    Type: Grant
    Filed: December 28, 1994
    Date of Patent: July 29, 1997
    Assignees: Hitachi, Ltd., Hitachi Cable, Ltd.
    Inventors: Osamu Suzuki, Heikichi Kuwahara, Kazumasa Fujioka, Syuuji Saitoo, Nobuo Suzuki, Koichi Isaka
  • Patent number: 5504924
    Abstract: An electronic computer cooling system having a cooling apparatus to cool an electronic computer and cooling members for thermally connecting semiconductor devices whose operating speeds are raised by cooling to a low temperature source of the cooling apparatus. Circuit boards onto which the semiconductor devices and the like constructing the electronic computer are mounted and the cooling apparatus such as a refrigerating apparatus and the like are compactly enclosed in a single casing. Or, the circuit boards and the cooling apparatus are compactly enclosed in separate detachable casings, respectively. Thus, a structure in which desired semiconductor devices can be certainly cooled by using the cooling members is obtained.
    Type: Grant
    Filed: September 26, 1994
    Date of Patent: April 2, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Shingeo Ohashi, Tadakatsu Nakajima, Heikichi Kuwahara, Toshio Hatada, Hitoshi Matsushima, Motohiro Sato, Hiroshi Inouye, Takao Ohba, Akira Yamagiwa
  • Patent number: 5365402
    Abstract: A cooling apparatus for an electronic device of high calorific density including an elastomer interposed between a semiconductor chip and a heat sink so as to connect them thermally. The elastomer may also be in close contact with a large number of semiconductor chips having various configurations which are mounted on a board, so that the elastomer is thermally connected with them, whereby the elastomer absorbs thermal deformations.
    Type: Grant
    Filed: November 29, 1991
    Date of Patent: November 15, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Toshio Hatada, Shigeo Ohashi, Tadakatsu Nakajima, Heikichi Kuwahara, Hitoshi Matsushima, Motohiro Sato, Hiroshi Inouye, Takao Ohba, Akira Yamagiwa, Kanji Otsuka, Yuuji Shirai
  • Patent number: 5270572
    Abstract: A semiconductor cooling unit for directly jetting a cooling medium against surfaces of semiconductor devices for use in a high-speed computer or the like to effectively remove heat from the semiconductor devices, in which partition members for partitioning a space into regions where semiconductor devices are placed. Each partitioned region has an opening at its ceiling side, and a pipe for supplying or discharging the cooling medium through the opening is disposed so as to project toward a central portion of the back surface of each semiconductor device. This pipe is utilized to also section a cooling medium supply header or a cooling medium return header so that bubbles generated from the semiconductor device surfaces can be smoothly removed, and so that the cooling medium can flow smoothly onto the semiconductor devices.
    Type: Grant
    Filed: June 24, 1992
    Date of Patent: December 14, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Tadakatsu Nakajima, Shigeo Ohashi, Heikichi Kuwahara, Noriyuki Ashiwake, Motohiro Sato, Toshio Hatsuda, Takahiro Daikoku, Toshio Hatada, Shigeyuki Sasaki, Hiroshi Inouye, Atsuo Nishihara, Kenichi Kasai
  • Patent number: 5021924
    Abstract: A multi-chip module or a like device having a sealed structure for being cooled with a liquid cooling medium, and in which the semiconductor integrated circuit chips or the chip carriers mounting the chips are individually cooled with the forced convection cooling using a cooling liquid. The cooling liquid injection ports are so arranged that the cooling liquid flows substantially in parallel with the back surfaces of the chips.
    Type: Grant
    Filed: September 14, 1989
    Date of Patent: June 4, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Shigekazu Kieda, Tadakatsu Nakajima, Heikichi Kuwahara, Motohiro Sato
  • Patent number: 4977444
    Abstract: Flexible cooling paths are connected to semiconductor elements which are heated members. A cooling apparatus comprises cooling blocks connected to cooling blocks, coolant flow paths through which the coolant flows, coolant branching mechanisms provided in the coolant flow paths and connecting mechanism for connecting the branching mechanism and the cooling blocks through O-rings. A part of coolant flowing through the cooling flow paths is introduced into the cooling blocks for the respective heated chips in order.
    Type: Grant
    Filed: October 24, 1988
    Date of Patent: December 11, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Tadakatsu Nakajima, Heikichi Kuwahara, Shigeo Ohashi, Motohiro Satoh, Toshihiro Yamada, Kenichi Kasai, Satomi Kobayashi, Akihide Watanabe
  • Patent number: 4794775
    Abstract: A method for producing a heat transfer tube for single-phase flow having rows of discontinuous projections formed on the inner surface thereof along one or more spiral curves. Each projection has a circular, elliptic or a similar cross-section constituted by smooth curves at any desired height including the bottom thereof. The cross-sectional area of the projection progressively decreases towards the top of the projection.
    Type: Grant
    Filed: December 23, 1986
    Date of Patent: January 3, 1989
    Assignees: Hitachi, Ltd., Hitachi Cable, Ltd.
    Inventors: Heikichi Kuwahara, Kenji Takahashi, Takehiko Yanagida, Wataru Nakayama, Shigeo Sugimoto, Kiyoshi Oizumi
  • Patent number: 4715436
    Abstract: A heat transfer tube has at least a row of projections provided on its inner surface at regular intervals along a spiral curve thereof. The row of projections are formed by plastic deformation of part of the heat transfer tube, which is effected by pressing a rolling disc having projections against the outer surface of the heat transfer tube. The projections have smooth curved surfaces. The height of the projections ranges from 0.45 mm to 0.6 mm, their pitch along the spiral curve ranges from 3.5 mm to 5 mm, and their pitch in the axial direction ranges from 5 mm to 9 mm.
    Type: Grant
    Filed: September 18, 1985
    Date of Patent: December 29, 1987
    Assignees: Hitachi, Ltd., Hitachi Cable, Ltd.
    Inventors: Kenji Takahashi, Heikichi Kuwahara, Takehiko Yanagida, Wataru Nakayama, Kiyoshi Oizumi, Shigeo Sugimoto
  • Patent number: 4690211
    Abstract: A heat transfer tube for single-phase flow having rows of discontinuous projections formed on the inner surface thereof along one or more spiral curves. Each projection has a circular, elliptic or a similar cross-section constituted by smooth curves at any desired height including the bottom thereof. The cross-sectional area of the projection progessively decreases towards the top of the projection.
    Type: Grant
    Filed: June 20, 1985
    Date of Patent: September 1, 1987
    Assignees: Hitachi, Ltd., Hitachi Cable, Ltd.
    Inventors: Heikichi Kuwahara, Kenji Takahashi, Takehiko Yanagida, Wataru Nakayama, Shigeo Sugimoto, Kiyoshi Oizumi
  • Patent number: 4653163
    Abstract: A method of producing a heat transfer wall, including a plurality of minute tunnels parallelly extending and spaced a minuscule distance from each other under an outer surface of the wall in contact with liquid, and a plurality of tiny hole portions formed at the outer surface of the wall above the tunnels and located at regular intervals along the tunnels to maintain same in communication with the outside. Each hole portion includes a projection located in the hole portion including a hole itself and extending from the vicinity of the hole portion into the hole portion in a manner to traverse same, so that a flow of liquid into the tunnels and a flow of vapor out of the tunnels can be optimally regulated by the projections to enable the heat transfer wall to exhibit a high heat transfer performance.
    Type: Grant
    Filed: August 27, 1985
    Date of Patent: March 31, 1987
    Assignees: Hitachi, Ltd., Hitachi Cable, Ltd.
    Inventors: Heikichi Kuwahara, Kenji Takahashi, Takehiko Yanagida, Wataru Nakayama, Shigeo Sugimoto, Yoshihiko Nakayama, Hiromichi Yoshida, Kiyoshi Oizumi, Toshi Sasaki, Shigeho Fukuda
  • Patent number: 4606405
    Abstract: In a perforated heat conductive surface structure having voids under an outer surface and openings in the outer surface, in order to obtain a high performance in particular at a low pressure and low temperature region, there is provided a heat transfer wall in which a thickness of a wall at a ceiling of each void and a length of a passage of the respective openings are increased in predetermined ranges.
    Type: Grant
    Filed: February 13, 1985
    Date of Patent: August 19, 1986
    Assignees: Hitachi, Ltd., Hitachi Cable, Ltd.
    Inventors: Wataru Nakayama, Tadakatsu Nakajima, Heikichi Kuwahara, Akira Yasukawa, Takahiro Daikoku, Hiromichi Yoshida
  • Patent number: 4602681
    Abstract: In a heat transfer wall provided with a plurality of cells and restricted holes, the cells are formed in a plurality of laminated layers in a direction from an outer surface of the heat transfer wall to an inside thereof, and the cells of the upper and lower layers and the outside of the outer surface are communicated to one another through the holes.
    Type: Grant
    Filed: October 26, 1983
    Date of Patent: July 29, 1986
    Assignee: Hitachi, Ltd. & Hitachi Cable, Ltd.
    Inventors: Takahiro Daikoku, Wataru Nakayama, Tadakatsu Nakajima, Heikichi Kuwahara, Hiromichi Yoshida
  • Patent number: 4585055
    Abstract: A liquid film evaporation type heat exchanger including a plurality of heat transfer units, with each unit including a plurality of flat heat transfer ducts of square cross section formed with a plurality of warm water passageways extending perpendicular to the direction of flow of a liquid medium, and a plurality of liquid distributing beams formed with a pluraity of cutouts. The heat transfer ducts and the liquid distributing beams being alternately arranged in the respective units, with the heat transfer units being arranged at locations spaced apart from each other in the direction of flow of the liquid medium. Vapor releasing ports are formed in positions between the adjacent heat transfer units. Each heat transfer duct has on either side surface thereof a porous material layer providing a heat exchange surface on which a film of the liquid medium is formed for evaporation.
    Type: Grant
    Filed: November 16, 1983
    Date of Patent: April 29, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Wataru Nakayama, Takahiro Daikoku, Tadakatsu Nakajima, Heikichi Kuwahara, Akira Yasukawa
  • Patent number: 4561497
    Abstract: In a heat transfer surface having cavity groups and restricted opening groups in an outer surface region, the cavity groups are composed of a plurality of rows of void strip members. The cavity strip members are arranged in parallel on a base member of the heat transfer surface and are laminated in one or more layers. Each strip member has a number of elongate cavities laterally arranged in parallel. The elongate cavities are closed at upper surfaces and have at both ends openings. The adjacent cavities in the same layer are communicated with each other by communicating portions each provided between the cavity strip members and by the openings. The restricted opening groups are formed on the upper surfaces of the communicating portions. The restricted opening groups render the communicating portions in one layer, the communicating portions in another layer and the outside to communicate with each another. The method of manufacturing such a heat transfer surface is also disclosed.
    Type: Grant
    Filed: December 14, 1983
    Date of Patent: December 31, 1985
    Assignees: Hitachi, Ltd., Hitachi Cable Ltd.
    Inventors: Tadakatsu Nakajima, Wataru Nakayama, Takahiro Daikoku, Heikichi Kuwahara, Akira Yasukawa, Katsuhiko Kasuya, Kazuaki Yokoi, Hideo Nakae, Hiromichi Yoshida
  • Patent number: 4195688
    Abstract: A heat-transfer wall kept at a low temperature so that hot vapor brought into contact with its surface condenses thereon. The surface is grooved at a fine pitch, having thin and sharply tapering ridges in between, with shallower fine-pitch grooves or notches formed in the ridges. The wall may be that of a tube, the grooves may consist of a continuous root in the form of a helix, and the ridges may be bent into the grooves to form rounded crests. The wall contour is made by forming fine-pitch shallow grooves crosswise by knurling and then forming fine-pitch deep grooves by cutting and turning up the surfaces in a plowing manner, for example on a lathe. A grooved die may be used to deform and bend the edges of the ridges toward the deep grooves.
    Type: Grant
    Filed: June 30, 1978
    Date of Patent: April 1, 1980
    Assignees: Hitachi, Ltd., Hitachi Cable, Ltd.
    Inventors: Kunio Fujie, Wataru Nakayama, Heikichi Kuwahara, Takahiro Daikoku, Kimio Kakizaki