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. 08, 2014
Filed:
Mar. 02, 2009
Daisuke Kozuka, Oyama, JP;
Masayuki Tajima, Oyama, JP;
Mitsumasa Akashi, Oyama, JP;
Shuuji Hori, Oyama, JP;
Daisuke Kozuka, Oyama, JP;
Masayuki Tajima, Oyama, JP;
Mitsumasa Akashi, Oyama, JP;
Shuuji Hori, Oyama, JP;
Komatsu Ltd., Tokyo, JP;
Abstract
A hydraulic servo drive device includes: a pilot spool for switching supply and shutoff of oil; a servo piston slid in accordance with the pilot spool; a stroke sensor for detecting a displacement of the servo piston; a first hydraulic chamber in which oil for moving the servo piston is flowed; a first piston oil path for communicating a pump port to which oil is supplied from a pump with a first hydraulic chamber; and a discharge circulating oil path for communicating the first hydraulic chamber with a drain port.