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:
Dec. 21, 2004
Filed:
Jul. 08, 2003
Applicant:
Inventors:
Atsuhiko Yokozeki, Shizuoka, JP;
Susumu Nakayama, Shizuoka, JP;
Kenji Tojo, Moriya, JP;
Akira Saruta, Chiba, JP;
Mutsunori Matsunaga, Shizuoka, JP;
Satoshi Kikuchi, Hitachi, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F25B 7/00 ;
U.S. Cl.
CPC ...
F25B 7/00 ;
Abstract
A refrigerating machine includes a plurality of compressors driven by motors each having an armature core incorporating a squirrel cage conductor and a permanent magnet which is magnetized so as to allow the motor to serve as a synchronous motor, and a compressor drive circuit for selectively driving the motor at a power source frequency by a commercial power source or at a variable frequency by an inverter. Thus, the overall efficiency of the refrigerating machine can be enhanced.