Patents by Inventor Etsuo Shibata

Etsuo Shibata 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).

  • Air conditioning apparatus returning refrigerating machine oil to compressor by two restrictors and method of controlling air conditioning apparatus
    Patent number: 5970722
    Abstract: An air conditioning apparatus includes a compressor, an interior side heat exchanger, an exterior side heat exchanger, an expansion device provided between the interior side heat exchanger and the exterior side heat exchanger, a four-way valve provided between the compressor and the interior side heat exchanger and between the compressor and the exterior side heat exchanger, an oil separator provided between a delivery outlet of the compressor and the four-way valve, a first restrictor and a second restrictor provided between the oil separator and a suction inlet of the compressor, and an open-close valve provided between the second restrictor and the suction inlet of the compressor.
    Type: Grant
    Filed: December 11, 1997
    Date of Patent: October 26, 1999
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Etsuo Shibata, Katsuhiro Wakahara, Kenji Yao