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. 07, 2003
Filed:
Sep. 26, 2001
Naoto Sannomiya, Tsuchiura, JP;
Sotaro Tanaka, Ushiku, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
A hydraulic recovery system for a construction machine comprises a recovery valve for supplying at least a part of a hydraulic fluid from a rod-side line, through which the hydraulic fluid is drained from a rod-side hydraulic chamber of an arm hydraulic cylinder, to a bottom-side line through a variable throttle, and a throttle valve for returning the remaining part of the hydraulic fluid, which is not recovered, from the rod-side line to a hydraulic reservoir through a variable throttle. Opening areas of those variable throttles are controlled depending on an arm flow rate supplied from hydraulic pumps to the arm hydraulic cylinder.