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:
Sep. 11, 2001
Filed:
Mar. 16, 2000
Hitachi, Ltd., Tokyo, JP;
Abstract
A compressed air production facility includes at least one variable speed compressor and a plurality of constant speed compressor, which are connected in parallel with one another. The variable speed compressor and the plurality of constant speed compressors are capacitively controlled with the use of a pressure in an air reservoir into which discharge air from these compressor are led. Both upper limit pressure at which the variable speed compressor is turned into its load operation mode into its unload operation mode and a lower limit pressure at which the variable speed compressor is turned into its unload operation mode into its load operation mode are set between an upper limit change-over pressure at which all of the plurality of constant speed compressors are turned into their load operation into their unload operation and a lower limit change-over pressure at which all of the plurality of constant speed compressors are changed over from their unload operation into their load operation. With this arrangement, it is possible to provide a power consumption characteristic which is substantially proportional to an air consumption.