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:
Aug. 16, 2011
Filed:
Mar. 20, 2009
Takashi Ohnuma, Kanagawa, JP;
Takao Nakadate, Kanagawa, JP;
Takashi Ohnuma, Kanagawa, JP;
Takao Nakadate, Kanagawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
There is provided with a cylinder apparatus comprising: a cylinder; a piston; a piston rod, one end of which is connected to the piston and the other end of which is extended outside; an external cylinder provided at an outer periphery of the cylinder so as to form a reservoir in which to seal the hydraulic liquid and gas therebetween; a base valve dividing the second chamber and the reservoir; a first check valve provided with the piston so as to allow flow of the hydraulic liquid only from the second chamber side to the first chamber side; a second check valve provided with the base valve so as to allow flow of the hydraulic liquid only from the reservoir side to the second chamber side; a flow passage connecting the first chamber with the reservoir; and an opening and closing valve opening and closing the flow passage.