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:
Jun. 25, 2002
Filed:
Jun. 04, 2001
Masao Kariya, Tsuchiura, JP;
Genroku Sugiyama, Ibaraki-ken, JP;
Hitachi Construction Machinery Co. Ltd., Tokyo, JP;
Abstract
An input/output port of a hose rupture control valve unit is attached to a bottom port of a hydraulic cylinder , and an input/output port is connected to one of actuator ports of a control valve via an actuator line . The valve unit comprises a poppet valve body serving as a main valve, a first spool valve body serving as a pilot valve operated with a pilot pressure supplied as an external signal and having a pilot variable throttle portion to operate the poppet valve body , a second spool valve body operated with a pilot pressure and having a sub-variable throttle portion to control a sub-flow rate, and a small relief valve having the function of an overload relief valve.