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:
Jul. 16, 2024
Filed:
Apr. 28, 2021
Applicant:
Kawasaki Jukogyo Kabushiki Kaisha, Kobe, JP;
Inventors:
Assignee:
KAWASAKI JUKOGYO KABUSHIKI KAISHA, Kobe, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E02F 9/22 (2006.01); E02F 9/20 (2006.01);
U.S. Cl.
CPC ...
E02F 9/2292 (2013.01); E02F 9/2037 (2013.01); E02F 9/2242 (2013.01); E02F 9/2267 (2013.01); E02F 9/2289 (2013.01); E02F 9/2004 (2013.01); E02F 9/2217 (2013.01);
Abstract
A hydraulic excavator drive system includes: a first pump that is connected to a head-side chamber of a boom cylinder by a head-side line and to a rod-side chamber of the boom cylinder by a rod-side line to form a closed circuit; and a second pump that supplies hydraulic oil to at least one of an arm cylinder or a bucket cylinder. The hydraulic excavator drive system further includes a switching valve located on a relay line that connects a supply line extending from the second pump to the rod-side line. The switching valve opens the relay line at a boom raising operation and blocks the relay line except at the boom raising operation.