Hydraulic jack control device as well as lifting and lowering device for the control method and the elevation of the elevating hydraulic jack

摘要

PROBLEM TO BE SOLVED: To stabilize lifting action of an article to be lifted by synchronizing lifting control of a plurality of lifting hydraulic jacks.;SOLUTION: The control devices 42 for lifting hydraulic jack are provided on every lifting hydraulic jack respectively. Function generation circuits 44 and 47 produce a position instruction signal for controlling a position of a piston based on a reference signal commonly used in the plurality of lifting hydraulic jacks respectively. Further, position adjustment circuits 46 and 49 control the position of the piston based on the position instruction signals produced by the function generation circuits 44 and 47 respectively. Thus, since the signal for controlling the piston is produced based on the common reference signal to all lifting hydraulic jacks, synchronization of the upper and lower pistons in the lifting hydraulic jack and control of the respective lifting hydraulic jacks can be synchronized.;COPYRIGHT: (C)2005,JPO&NCIPI