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:
Apr. 08, 1986
Filed:
Jan. 04, 1985
Yozo Shibata, Hitachi, JP;
Mitsuji Konishi, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Disclosed is a method of controlling the operation of a plurality of compressors each having at least one capacity controller capable of changing the discharge rate of the compressor in a stepped manner in such a manner as to provide a total discharge rate just meeting the load demand which varies momentarily. In this method, the control system is divided into a capacity control loop for responding to comparatively small load variance and a compressor control loop for responding to a comparatively large load variance. The capacity control loop is further divided into a sub-loop for capacity controllers of a compressor which has worked longest and which is to be stopped first and a sub-loop for the capacity controllers of other compressors. The unloading operation is commenced preferentially with the sub-loop for the capacity controllers of the compressor to be stopped first, while the on-loading operation is made first with the sub-loop for the capacity controllers of other compressors.