| 摘要 |
PROBLEM TO BE SOLVED: To provide a working attachment control device for construction machine, which can control a safety valve for preventing fall of a working attachment without response delay even when work at a high altitude is carried out by using a long attachment. SOLUTION: The construction machine is formed of a machine main body, the working attachment mounted thereon, and a hydraulic actuator for operating the attachment. According to the construction machine, an actuator circuit for activating the hydraulic actuator 3 has a safety valve 6b arranged thereacross. The opening of the safety valve 6b has an interruption position at which lowering of the working attachment is halted, and the opening is controlled to be set at a communicating position from the interruption position in response to an electric input signal.
|
