HYDRAULIC CIRCUIT

• Main Authors: MATSUO TSUTOMU, YASUFUKU AKIRA, ISHIKAWA KAZUO, UEDA SUKENORI, ISHIKAWA HIROHIKO
• Format: Patent
• Language: English
• Published: 25.06.2009
• Subjects: BLASTING; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR; FLUID-PRESSURE ACTUATORS; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; HAULING; HEATING; HOISTING; HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDEDFOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCEDIRECTLY TO THE SURFACE OF A LOAD; HYDRAULICS OR PNEUMATICS IN GENERAL; LIFTING; LIGHTING; MECHANICAL ENGINEERING; PERFORMING OPERATIONS; SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; TRANSPORTING; WEAPONS

PROBLEM TO BE SOLVED: To provide a hydraulic circuit for reducing the size of a generator, having a longer time for continuously rotating a pump motor with inertia even after a change-over valve is operated to establish the condition that pressurized liquid to be returned to a tank during lower load is not supplied to a pump motor, than prior-art one. SOLUTION: Into a bottom chamber 12a of a lift cylinder 12 which drives a fork 11, an operating oil in the operating oil tank 16 in an opened condition is supplied with a hydraulic pump 17 driven by the motor 18. In a return duct 20 for returning the operating oil from the bottom chamber 12a to the operating oil tank 16, the hydraulic motor 21 is provided for driving the generator 22. The bottom chamber 12a is changed over between the condition of being communicated with the hydraulic pump 17 and the condition of being communicated with the return duct 20 by a lift control valve 14. A check valve 24 which is opened to introduce air from the outside of the duct when pressure in the return duct 20 is negative is provided at the upstream side of the return duct 20 beyond the hydraulic motor 21. COPYRIGHT: (C)2009,JPO&INPIT