BRAKE SYSTEM FOR MOTOR LOADING/UNLOADING VEHICLE

摘要

PURPOSE:To alleviate brake impact at the time of quick turning and to suppress variation of centrifugal acceleration in a motor loading/unloading vehicle such as forklift by providing a plugging brake means and a quick turn detecting means thereby lowering the plugging brake force of a travel motor upon detection of quick turning. CONSTITUTION:At the time of plugging brake, a regenerative contactor MG in a traveling circuit 9 is closed at first and drive/reverse contactors MR, MF are switched to the opposite side as compared with powering time thus imparting torque on a travel motor in reverse direction. A computor 7 makes a decision of quick turning if a steering angle read through a steering angle sensor 2 is larger than a predetermined threshold and determines a plugging set current from a current-pedal step angle map stored in a memory. The plugging set current at the time of quick turning is set lower than that at straight advancing. A current detected through a current sensor 4 is then compared with a set current and the brake force is regulated according to the duty ratio of gate voltage to be applied on a transistor TM.