CONTROL DEVICE SAFETY SYSTEM FOR CONSTRUCTION EQUIPMENT HAVING DUAL CONTROL SYSTEM

摘要

Provided is a controller safety system for a construction machine which includes: a main controller and a subsidiary controller respectively having CPUs which receive an electric control signal generated from the construction machine to provide electric operation and electronic control function of the construction machine; and an output control circuit for outputting command signals generated through the main controller and the subsidiary controller to an electronic control valve. The controller safety system for the construction machine comprises: a control unit having a diagnostic circuit for determining whether the command signal of the main controller is a normal signal or an abnormal signal; and a switching circuit which blocks the command signal of the main controller when the command signal of the main controller is abnormal and makes the command signal of the subsidiary controller be outputted to the output control circuit. The controller safety system for the construction machine according to the present invention can diagnose and determine errors on various electrically operating parts or on a circuit of the main controller of the control system providing the electronic control function and transfer the electric and electronic control functions to the subsidiary controller, thereby enhancing reliability of the system by preventing malfunction of the construction machine. Additionally, the controller safety system can monitor mutual operation states of the controllers through communication between the controllers to make the subsidiary controller emergently cope with malfunction of the main controller, thereby reinforcing its diagnostic function.