ANTI-THEFT DEVICE FOR CONSTRUCTION MACHINE

摘要

PROBLEM TO BE SOLVED: To provide an anti-theft device inhibiting theft even to a person having some knowledge of a construction machine. SOLUTION: A construction machine has operation quantity input devices 23-28; valves 14-19 for controlling hydraulic actuators according to the operation quantities of the operation quantity input devices 23-28; and a control circuit for outputting control signals for changeover-controlling the valves 14-19 on the basis of the operation signals of the operation quantity input devices 23-28. The construction machine is further provided with an input means 35 for inputting the cipher number, and a control circuit 22 for comparing the cipher number of the input means 35 with a prestored cipher number and cutting off the input of the operation signals to the valves 14-19 in the case of noncoincidence of the cipher numbers.