an emergency braking device for hoisting drum of an overhead travelling crane

摘要

PURPOSE: An emergency brake system for a hoisting drum of an overhead traveling crane is provided to prevent winded materials from suddenly falling down by immediately stopping the rotation of the hoisting drum, even if a brake lining is omitted from a brake shoe constraining the hoisting drum by a braking drum. CONSTITUTION: An emergency brake system for a hoisting drum of an overhead traveling crane is composed of a rotational frequency indicating plate(21) attached on an outer peripheral surface of the hoisting drum to rotate with interlocking with the hoisting drum, a sensor(23) detecting the rotational frequency of the indicating plate, a control unit controlling the working of a driving motor(27) according to the rotational frequency detected by the sensor, the driving motor operating a rotary plate assembly to the signal of the control unit, and the rotary plate assembly stopping the rotation of the hoisting drum by protruding a brake lever(38) out of the outer peripheral surface of the hoisting drum by a rotary plate(33) rotated by the driving motor.