TOWER CRANE HOISTING DEVICE HAVING FALL-PREVENTING FUNCTION

摘要

PURPOSE: A tower crane hoisting device having fall-preventing function is provided to prevent an accident and the breakage of equipments by preventing the falling of a load when the load is interrupted during hoisting. CONSTITUTION: A motor speed sensor(210) installed in a hoist motor(110) senses the rotational speed of the hoist motor. A drum speed sensor(220) installed on a hoist drum shaft(152) for winding a wire rope(160) senses the rotational speed of the hoist drum. A control unit(230) generates a drum control signal by calculating the rotational difference of the motor and the hoist drum. A brake(250) forms a final actuator for the operation of the signal generated from the control unit and controls the rotation of the hoist drum. A torque limiter(240) installed between the hoist motor and a speed reducer(120) performs physical connection of the hoist motor and the speed reducer and disconnects the hoist motor from the speed reducer. When a load is interrupted during hoisting, the rotation of the hoist drum is restrained. Thus, the falling of the load is prevented.