The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 31, 2017
Filed:
Jan. 15, 2010
Mamoru Hamada, Chiyoda-ku, JP;
Fumitake Unezaki, Chiyoda-ku, JP;
Yoshihiro Takahashi, Chiyoda-ku, JP;
Kengo Takahashi, Chiyoda-ku, JP;
Kazuki Okada, Chiyoda-ku, JP;
Hirokazu Minamisako, Chiyoda-ku, JP;
Shinichi Uchino, Chiyoda-ku, JP;
Mamoru Hamada, Chiyoda-ku, JP;
Fumitake Unezaki, Chiyoda-ku, JP;
Yoshihiro Takahashi, Chiyoda-ku, JP;
Kengo Takahashi, Chiyoda-ku, JP;
Kazuki Okada, Chiyoda-ku, JP;
Hirokazu Minamisako, Chiyoda-ku, JP;
Shinichi Uchino, Chiyoda-ku, JP;
MITSUBISHI ELECTRIC CORPORATION, Chiyoda-ku, Tokyo, JP;
Abstract
In a heat pump apparatus, it is aimed to enhance efficiency of a defrost operation by reducing a loss of heat radiation during the defrost operation and reducing a compressor input during the defrost operation. The heat pump apparatus includes a main refrigerant circuit in which a compressor, a first heat exchanger, an expansion mechanism, and a second heat exchanger are connected sequentially, and also includes a bypass circuit including an on-off valve and providing a connection by bypassing the expansion mechanism. The main refrigerant circuit includes a four-way valve that switches between a heating operation and the defrost operation by switching an order in which the refrigerant circulates through the main refrigerant circuit. The main refrigerant circuit also includes a first temperature detection unit and a second temperature detection unit. Based on values detected by these temperature detection units, a degree of superheat of the first heat exchanger during the defrost operation is computed. When the heating operation is switched to the defrost operation, the heat pump apparatus increases a circulation amount of the refrigerant circulating through the refrigerant circuit by opening the on-off valve, and also controls an operation frequency of the compressor such that the degree of superheat is at a predetermined target value.