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:
Feb. 05, 2013
Filed:
Jul. 24, 2008
Hajime Sato, Aichi, JP;
Yoshiyuki Kimata, Aichi, JP;
Hajime Sato, Aichi, JP;
Yoshiyuki Kimata, Aichi, JP;
Mitsubishi Heavy Industries, Ltd., Tokyo, JP;
Abstract
A multi-stage compressor is provided that reliably prevents liquid compression in a higher stage compression mechanism and also prevents compression efficiency degradation resulting from overheating of injection refrigerant and from the lubricating oil being raised up together with the injection refrigerant. An injection circuit is branched into a plurality of circuits. A first circuit thereof is communicatively connected to an inside space of a closed housing that is at the same side as the higher stage compression mechanism with respect to an electric motor, and a second circuit is communicatively connected to an inside space of the closed housing that is opposite from the higher stage compression mechanism with respect to the electric motor. The first circuit and the second circuit are provided with a switching mechanism for switching the injection circuit to the first circuit or the second circuit according to the dryness of the injection refrigerant.