Action principle: when the brake power input pole brake coil is energized, the brake pole group magnetic and suction plywood attract back to the surface of the pole group, so suck gap between the plywood and the brake plate, causing the brake open , motor began operation. The power outage, suck plywood unattractive, the the pole group within the compression spring will suck plywood pushed back, causing friction between the brake plate, resulting in brake effect. Features: Compact structure, big torque, safe and reliable, low noise. Using dual-friction surface, the brake torque is large compared to the single-sided friction torque. High efficiency, long life. Directly mounted in the axial end of the rotary shaft, the brake is energized before the normal operation, external manual release when the power artificial eliminate braking torque;