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:
Apr. 08, 1997
Filed:
Dec. 29, 1995
Hyun G Ko, Incheon, KR;
Daewoo Heavy Industries Ltd., Incheon, KR;
Abstract
A hydraulic control system is provided for use in a forklift truck having an engine, a steering cylinder, a lift cylinder, a tilt cylinder, a steering pump rotatably driven by the engine for producing a steering fluid under pressure to actuate the steering cylinder and a main pump for generating a working fluid under pressure to actuate the lift and tilt cylinders. The system includes a steering control valve unit for changing flow path of the steering fluid to control movement of the steering cylinder, a priority valve lying between the steering pump and the steering control valve unit for supplying the steering control valve unit with a controlled amount of the steering fluid, a main control valve unit selectively connected to the main pump and adapted to control movement of the lift and tilt cylinders and a stall valve remaining, when the engine is rotating at no greater than a preselected rpm, in a first position in which the working fluid is bypassed to the priority valve and, when the engine is rotating at greater than the preselected rpm, shifted to a second position in which the working fluid is fed to the main control valve unit.