Patents by Inventor Takenobu Kajikawa

Takenobu Kajikawa 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: 5318743
    Abstract: A process for producing a thermoelectric material comprises molding a material powder comprising two or more elements selected from the group consisting of bismuth, tellurium, antimony and selenium and having average diameter in the range from 0.05 to 100 .mu.m and sintering the molded material powder with or without hot isostatic pressing. The material powder may be calcinated before the molding. A process for producing a thermoelectric element comprises cutting out pieces of a pillar-like shape from each of a p-type thermoelectric material and a n-type thermoelectric material, connecting the pieces cut out from the p-type thermoelectric material and the pieces cut out from the n-type thermoelectric material alternately with electrodes at the upper faces or the lower faces of the pieces and attaching insulating base plates to the surfaces of the electrodes. The p-type thermoelectric material and the n-type thermoelectric material are respectively produced by the process described above.
    Type: Grant
    Filed: November 27, 1992
    Date of Patent: June 7, 1994
    Assignees: Idemitsu Petrochemical Co., Ltd., Director-General, Agency of Industrial Science and Technology, Ministry of International Trade and Industry
    Inventors: Takeo Tokiai, Takashi Uesugi, Kazuyuki Fukumoto, Toshitaka Ohta, Takenobu Kajikawa
  • Patent number: 5246504
    Abstract: A thermoelectric material can be obtained by co-pulverizing and mixing a material containing at least bismuth and a material containing at least tellurium, without being alloyed by melting, and then molding and sintering. This thermoelectric material has high performance and can be utilized in a variety of fields such as thermoelectric power generation and thermoelectric cooling, a temperature sensor, space development, marine development, and electric power generation in the remote areas. Since metal elements are used as a starting material, the starting material can be easily prepared. Moreover, in the production steps, the thermoelectric material can be produced in a high yield at a low energy consumption level by a simplified manner, without a complicated operation or special apparatus, and its production cost can be decreased.
    Type: Grant
    Filed: January 10, 1992
    Date of Patent: September 21, 1993
    Assignees: Director-General, Agency of Industrial Science and Technology, Ministry of International Trade and Industry, Idemitsu Petrochemical Co., Ltd.
    Inventors: Toshitaka Ohta, Takenobu Kajikawa, Takashi Uesugi, Takeo Tokiai
  • Patent number: 5108515
    Abstract: A thermoelectric material can be obtained by co-pulverizing and mixing a material containing at least bismuth and a material containing at least tellurium, without being alloyed by melting, and then molding and sintering. This thermoelectric material has high performance and can be utilized in a variety of fields such as thermoelectric power generation and thermoelectric cooling, a temperature sensor space development, marine development, and electric power generation in the remote areas. Since metal elements are used as a starting material, the starting material can be easily prepared. Moreover, in the production steps, the thermoelectric material can be produced in a high yield at a low energy consumption level by a simplified manner, without a complicated operation or special apparatus, and its production cost can be decreased.
    Type: Grant
    Filed: November 6, 1989
    Date of Patent: April 28, 1992
    Assignees: Director-General, Agency of Industrial Science and Technology, Ministry of International Trade
    Inventors: Toshitaka Ohta, Takenobu Kajikawa, Takashi Uesugi, Takeo Tokiai
  • Patent number: 5103286
    Abstract: A thermoelectric module comprising a first electrode array having a plurality of electrode pieces and a second electrode array having a plurality of electrode pieces. The first and second electrode arrays are spaced apart from each other. The electrode pieces of the first electrode array are alternately connected with the electrode pieces of the second electrode array via thermoelectric elements. The connections are such that one end portion of each electrode piece of the first electrode array is connected with one end portion of an electrode piece of the second electrode array through a thermoelectric element of a first conductive type. The other end portion of an electrode piece of the first electrode array is connected with one end portion of another electrode piece of the second electrode array through a thermoelectric element of a second conductive type. The weight per unit output of the thermoelectric module is small.
    Type: Grant
    Filed: November 3, 1989
    Date of Patent: April 7, 1992
    Assignee: Agency of Industrial Science and Technology
    Inventors: Toshitaka Ohta, Takenobu Kajikawa
  • Patent number: 4902648
    Abstract: A thermoelectric module comprises a first electrode array having a plurality of electrode pieces and a second electrode array having a plurality of electrode pieces. The first and second electrode arrays are confronted with each other. The electrode pieces of the first electrode array are alternately connected with the electrode pieces of the second electrode array in such a way that one end portion of each electrode piece of the first electrode array is connected with one end portion of an electrode piece of the second electrode array through a thermoelectric element of first conductive type while the other end portion of the each electrode piece of the first electrode array is connected with one end portion of another electrode piece of the second electrode array through a thermoelectric element of second conductive type. The weight per unit output of the thermoelectric module is small.
    Type: Grant
    Filed: January 3, 1989
    Date of Patent: February 20, 1990
    Assignee: Agency of Industrial Science and Technology
    Inventors: Toshitaka Ohta, Takenobu Kajikawa