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. 12, 2023
Filed:
Dec. 10, 2019
Kawasaki Jukogyo Kabushiki Kaisha, Kobe, JP;
Akihiro Kondo, Kobe, JP;
Kazuya Iwabe, Kobe, JP;
KAWASAKI JUKOGYO KABUSHIKI KAISHA, Kobe, JP;
Abstract
A hydraulic drive system raises and lowers an object by supplying and discharging operating oil to and from each of two ports of an actuator and includes a control device, first to third electromagnetic proportional control valves, a hydraulic pump, a control valve, and a lock valve. When a second pilot pressure is output, the control valve causes the operating oil to be discharged from a first port in order to lower the object. The lock valve is disposed so as to be able to prevent the operating oil from being discharged from the first port by closing a path between the first port and the control valve, and only when a third pilot pressure is output, allows the operating oil to be discharged from the first port by opening the path between the first port and the control valve.