Patents Assigned to The Tokyo Electric Power Company, Ltd.
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Patent number: 5209645Abstract: A gas turbine bucket and a gas turbine nozzle applied with a ceramic coating comprises a base material of the bucket and the nozzle made of a heat resisting alloy; a plurality of coating layers for the front portion consisting of, a mixture layer which comprises a ceramic material and metal and which is formed on the base material, an alloy layer which comprises an alloy material exhibiting excellent resistance to high temperature oxidation and corrosion and which is formed on the mixture layer, and a ceramic layer which comprises ceramic material and formed on the alloy layer. Such ceramic coating has a satisfactory thermal barrier effect on the base material of the gas turbine bucket and nozzle.Type: GrantFiled: June 15, 1990Date of Patent: May 11, 1993Assignees: Hitachi, Ltd., The Tokyo Electric Power Company, Ltd.Inventors: Yoshitaka Kojima, Akira Mebata, Noriyuki Ohnaka, Akihiko Chiba, Ryoichiro Ohoshima, Norio Watanabe, Yukiyoshi Hara
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Patent number: 4955082Abstract: A mobile station receives radio waves from all signposts through the positioning channels while making communications using the voice channels. The signal levels of the radio waves thus received are subjected to comparison, so that a zone switching request is made to a signpost with the highest signal level, whereby a mobile station can make communication through that signpost which covers the zone where the mobile station is located, even while traveling. The positioning channels are so set that the frequencies assigned to the signposts are switched every frame in a time series mode, and none of the signposts transmit one and the same frequency at the same time. Therefore, the mobile station can receive radio waves from all the signposts without signal interference (which may be caused when a plurality of stations transmit signals equal in frequency). In the system of the invention, the transmission zones of adjacent signposts overlap each other.Type: GrantFiled: January 11, 1989Date of Patent: September 4, 1990Assignees: The Tokyo Electric Power Company Ltd., Sumitomo Electric Industries, Ltd.Inventors: Seiji Hattori, Akihide Kasukawa, Yoshizo Shibano, Yoshinobu Kobayashi, Shinji Suzuki
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Patent number: 4947452Abstract: A mobile communication system is provided wherein a plurality of signposts enable communications among mobile stations and a switching system in a predetermined communicating area, and are connected through a transmission network connected to a fixed network according to the invention, each of the signposts has dual zone communications ability including a communicating area which overlaps the communicating areas or adjacent signposts, and a zone switching signal area which does not overlap the zone switching signal areas of adjacent signposts. The signpost and mobile stations, jointly detect on-going signal levels of the mobile station, and communication area switching operation are carried out as needed. In the mobile communication system of the invention, a transmitting and receiving equipment can be a single transceiver which switches over the frequencies to communicating channel frequencies and to zone switching controlling frequencies.Type: GrantFiled: January 11, 1989Date of Patent: August 7, 1990Assignees: The Tokyo Electric Power Company, Ltd., Sumitomo Electric Industries, Ltd.Inventors: Seiji Hattori, Akihide Kasukawa, Yoshizo Shibano, Yoshinobu Kobayashi, Shinji Suzuki
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Patent number: 3944886Abstract: A protecting apparatus for a series capacitor in an AC power circuit includes an enclosure filled with a low pressure insulating gas. A discharge gap device, a bypass switch for the series capacitor and an electromagnetic repulsion device for closing the bypass switch in response to the discharge of the series capacitor are assembled in the enclosure in alignment with each other. A metallic cylinder is provided around the assembly forming a return path for the capacitor discharge current to cooperate with the gap device and its support. In this way, the impedance of the capacitor discharge passage can be effectively reduced to permit rapid removal of excess terminal voltage from the series capacitor.Type: GrantFiled: January 24, 1975Date of Patent: March 16, 1976Assignees: Tokyo Electric Power Company, Ltd., Tokyo Shibaura Electric Company, Ltd.Inventors: Yotsuo Ishida, Takeo Okazaki, Hajime Matsumura, Shinichi Menju, Iwao Ohshima