DRIVE CONTROL DEVICE FOR HYDRAULIC CYLINDER OF CONSTRUCTION MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a drive control device for a hydraulic cylinder of a construction machine in which the length of a cushion area is not considerably changed even when the lever input of an operation lever device is changed, the front attitude to start the automatic deceleration is substantially constant, and the operability is excellent. SOLUTION: The cylinder stroke Sa of an arm cylinder 209 is operated from the turning angle of an arm obtained from the signal of an angular sensor 22, and the pilot pressure upper limit value Pi2 by the cylinder stroke Sa is operated by using a pilot pressure upper limit table. The pilot pressure upper limit coefficient Ku is operated by using the pilot pressure upper limit table from the lever input signal of an operation lever device 5b. The pilot pressure upper limit value Pi2 with the input corrected is obtained by multiplying the pilot pressure upper limit coefficient Ku. The minimum value is selected from the target pilot pressure Pi1 and the pilot pressure upper limit value Pi3 with the lever input corrected, and the smaller value is obtained as the output pilot pressure Pi. The command current according to the output pilot pressure Pi is output. COPYRIGHT: (C)2004,JPO&NCIPI