Hitachi, Ltd.

Hitachi Automotive Systems, Ltd.

Hitachi Construction Machinery Co., Ltd.

Shuichi Terakado

Takeshi Tanaka

Kiyoshi Nakata

Takayuki Atarashi

Yutaka Matsunobu

Shigeo Ohashi

Katsumi Ishikawa

Takashi Naganawa

Rintaro Minamitani

Atsuo Nishihara

Shingo Shirakawa

Keisuke Horiuchi

Takashi Kaneko

Noriyoshi Urushiwara

Sunao Funakoshi

Yasunori Ota

Satoshi Yamamura

Kazutoshi Ogawa

Kento Mochizuki

Shigekazu Kieda

Yosuke Yasuda

Takeo Takagi

Tomomi Kanazawa

Tomoo Hayashi

Shinya Okumura

Takeshi Shinomiya

Hiroshi Akai

Kuniaki Otsuka

Shigehisa Funabashi

Naoki Yotsumoto

Naoki Kunihiro

Hideaki Mori

Hiroyuki Shirata

Taku Yamamoto

Masayuki Wada

Kiyoshi Terasawa

Yuta Oura

Naoya Hashiguchi

Yasuhiro Nagaura

This three-phase AC motor drive device is provided with: a load; an inverter devicefor driving the load; an MCOK_A_connected between the inverter deviceand the load and electrically connecting or disconnecting the inverter deviceto or from the load; a voltage detectorhaving terminals respectively connected to the circuits of at least two phases to detect the voltages between the three phases; and a current detectorfor detecting the currents of the three phases. In the connection from the inverter deviceto the load, the inverter device, the MCOK_A_, the voltage detector, the current detector, and the load are aligned in this order.

Three-phase AC motor drive device, rail vehicle equipped with same, and three-phase AC motor drive method

A power conversion device achieves size reduction and reliability by reducing the number of components of the system. The power conversion device has a semiconductor module of a half-bridge configuration in which two semiconductor elements are arranged in series. The semiconductor module has a cuboidal shape and has, along a longitudinal direction thereof, a positive pole terminal, a negative pole terminal, and terminals for inputting or outputting alternating current or for forming a single phase of the power conversion device. In the vertical direction corresponding to a widthwise direction of the cuboid, a plurality of the semiconductor modules are arranged vertically, forming a plurality of phases of the power conversion device. The semiconductor modules of the plurality of phases are installed in contact with a cooling unit, and one or more capacitors are disposed so as to face the cooling unit across the semiconductor modules of the plurality of phases.

Power conversion device and electric railroad vehicle equipped with power conversion device

A gear-integrated electric motor is provided with a motor () generating a driving force by input of electricity, a gear mechanism () converting the driving force of the motor, and a housing () containing the motor and the gear mechanism, and used in a horizontal position in which a motor shaft () and a gear output shaft () become substantially horizontal. The gear-integrated electric motor includes at least one heat pipe () which has an evaporation portion () disposed in a motor area of the housing, and a condensation portion () disposed in a gear mechanism area of the housing and higher than the evaporation portion with respect to the vertical direction in the horizontal position.

Gear-integrated electric motor and electric vehicle

The construction machine including an engine room having an engine, a radiator ii for cooling the engine, and a hydraulic pump which are arranged therein, and a counterweight area which is located adjacent to the engine room and in which batteries are installed, a ventilation passage for cooling the engine room and a ventilation passage for cooling the batteries are formed separately and independently in the substantially same direction, and a flowing direction of cooling air flowing in the ventilation passage for cooling the engine room and a flowing direction of cooling air flowing in the ventilation passage for cooling the batteries are substantially parallel to each other.

Cooling structure for construction machine

An edge light display unit includes light generating sources, a substrate mounting the light generating sources, a lens, a diffusion plate expanding light input in a side surface of the diffusion plate as to irradiate a front surface of the diffusion plate, and a heat sink thermally contacted with the substrate. A base portion of the heat sink has a substrate mounting surface and a fin constituting surface substantially perpendicular to the substrate mounting surface. At least one fin extends from the fin constituting surface in a direction substantially perpendicular thereto and along the plurality of light generating sources in a direction parallel to substrate. An air supply and exhaust surface of a cooling air are formed in a back surface side of the display unit.

Display unit

In an electronic apparatus having a heat-generating element therein, a cooling jacketfor transmitting heat generated from the heat-generating elementinto to a liquid coolant flowing therein, comprises: a coverbuilding up a heat transfer surface to be in contact with a surface of the heat-generating element; a passagefor the liquid coolant, which is formed neighboring with the heat transfer surface and wound round in a 'S'-like manner within an inside of a main bodyof the cooling jacket; and an inletand an outletattached at both ends of the flow passage of the liquid coolant, and further a dispersion memberis disposed in the flow passage, being built up by gathering a plural number of members, each of which has a 'U'-like cross-section of an aspect ratio from 10 to 20, thereby diffusing the liquid coolant therein, so as to transfer the heat from the heat-generating element thereto with high efficiency, and thereby enabling to cool down the heat-generating element, fully, even with a relatively small amount or volume of the liquid coolant.

Cooling jacket

An object of the present invention is to provide a thyristor valve arrester capable of measuring leakage currents of arrester elements in a simple construction and a DC power transmission thyristor valve having it used therein. A multiple of laminated arrester sets are arranged in parallel with a multiple of thyristor valves. Each arrester set is made of a plurality of arrester units arranged in parallel. Each adjoining arrester sets has through an insulator an inter-stage connecting conductor therebetween at a position corresponding to the respective thyristor valve terminals. An end of each arrester set and the respective inter-stage connecting conductors have a leakage current ammeter and a surge counter connected therebetween in electrical parallel. Each inter-stage connecting conductor and the respective thyristor valve stage are connected together by a thyristor valve connecting conductor.

Thyristor valve arrester and DC power transmission thyristor valve using

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Mito, Japan

Shuichi Terakado