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:
Oct. 05, 2021
Filed:
Jul. 31, 2018
Kawasaki Jukogyo Kabushiki Kaisha, Kobe, JP;
Hideki Tanaka, Nishinomiya, JP;
Hideki Watanabe, Kobe, JP;
Isamu Yoshimura, Kobe, JP;
Tomohide Hattori, Kobe, JP;
Mariko Ogata, Kobe, JP;
Tadashi Anada, Kobe, JP;
KAWASAKI JUKOGYO KABUSHIKI KAISHA, Kobe, JP;
Abstract
A hydraulic drive apparatus includes: an electric motor; a variable displacement pump driven by the electric motor, the pump including a pair of pump ports whose delivery side and suction side are switched with each other in accordance with a rotation direction of the electric motor; a hydraulic actuator connected to the pair of pump ports by a first supply/discharge line and a second supply/discharge line; and a control device that controls the electric motor based on an actuator position command value for the hydraulic actuator. The pump is configured such that a volume of the pump decreases in accordance with increase in a pressure difference between the first supply/discharge line and the second supply/discharge line.