CONTROL METHOD OF HYDRAULIC CONTROL DEVICE FOR CARGO HANDLING

• Main Authors: MATSUO TSUTOMU, UEDA SUKENORI, INOUE HIROSHI, ISHIKAWA HIROHIKO
• Format: Patent
• Language: English
• Published: 13.01.2011
• 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 control method of a hydraulic control device for cargo handling, capable of stabilizing operation when a hydraulic cylinder for cargo handling existing in a stopping state operates.SOLUTION: In a forklift, when an operation angle θ1 of a lift lever 22 is 0 degree, a CPU 61 puts a lifting solenoid valve 32 in a closed state, and does not drive a lifting pump motor 31. When the operation angle θ1 of the lift lever 22 exists in a dead zone, the CPU 61 puts the lifting solenoid valve 32 in the closed state, and rotates the lifting pump motor 31 at a lifting starting rotating speed. When the operation angle θ1 of the lift lever 22 goes over the dead zone, the CPU 61 puts the lifting solenoid valve 32 in an opening state, and rotates the lifting pump motor 31 at a lifting operation rotating speed of adding a rotating speed of increasing in proportion to the operation angle θ1 to the lifting starting rotating speed.