LIFTING AND LOWERING APPARATUS OF TRAVELING VEHICLE FOR WORKING

摘要

PROBLEM TO BE SOLVED: To provide a lifting and lowering apparatus for traveling vehicles for working in which smooth horizontal control scarcely causing shock can be kept even when a field state is diversely different by carrying out positive changeover of sensitivity without changing a dead zone. SOLUTION: When a mode exchange switch is changed over from an ordinary control mode to an adjustment mode, a control electric current value obtained when a lift rod cylinder 12 starts extension from the shortest position is stored by a horizontal control means and when the mode exchange switch is changed over from the adjustment mode to a sensitivity changeover mode, a plurality of output ratio characteristics determined by the difference between an output ratio changing from a minimum value of control electric current fed to a lift rod value 13 to a maximum value thereof and the change of expansion and contraction length of the lift rod cylinder 12 detected by the detection means are stored in the horizontal control means and a sensitivity of horizontal control is changed over by changeover of the each output ratio characteristic.