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. 23, 2007
Filed:
Mar. 14, 2005
Yutaka Toji, Hiroshima, JP;
Yoichiro Yamazaki, Hiroshima, JP;
Hidekazu Oka, Hiroshima, JP;
Kobelco Construction Machinery Co., Ltd., Hiroshima-shi, JP;
Abstract
A hydraulic control system for a working machine according to the present invention includes a regulator control valve for controlling an operation of a pump regulator and a controller for sending a control signal for changing a discharge quantity of the pump to the regulator control valve in accordance with an operation amount of an operating device. This system further includes a fail-safe valve disposed in a control line joining the pump regulator and the regulator control valve. The fail-safe valve is configured so as to switch from an ordinary position to a fail-safe position in accordance with a failure signal indicative of failure in the regulator control valve.