Patent ID: 7281612

Claim:
A brake structure for a roll-up door, comprising a brake drum, for being fixed to a transmission shaft of a speed reducer, the brake drum receiving a pair of brake shoes in opposite inner sides thereof, the brake shoes being pivotably connected to each other at an end of each brake shoe, a linking resilient member being connected between the free ends of the brake shoes, a brake pad being attached to a surface of each brake shoe facing the inner surface of the brake drum; a controlling lever, for being disposed at the top of the speed reducer corresponding to the free ends of the brake shoes, one end of the controlling lever being connected to an end of a fixing resilient member, the other end of the fixing resilient member being connected to a moving iron of a first solenoid, a clasping block being connected to the moving iron of the first solenoid, the other end of the controlling lever being connected to a moving iron of a second solenoid, the first solenoid and the second solenoid being disposed at the top of the speed reducer; a controlling block disposed at the controlling lever between the free ends of the brake shoes and in contact to the free ends of the brake shoes; and a brake control solenoid for being disposed at the top of the speed reducer, the brake control solenoid being connected to a power supply with capacitance character, a moving iron of the brake control solenoid being connected to a connecting rod mechanism, the clasping block being connected to the connecting rod mechanism.