我厂有数台CD1、MD1型电动葫芦,在使用中频频发生制动失灵的故障。经检修发现,由于紧固联轴器的螺钉3(图1)松动,限制了电机轴4的轴向移动量,使风扇制动轮不能与锥形制动环(图中未画)接触,导致制动失灵。这种故障大多发生在吊起重物后,具有隐蔽性、突发性, Our factory has several CD1, MD1 electric hoist, frequently used in the use of brake failure failure. After inspection, it is found that the axial movement of the motor shaft 4 is limited due to the looseness of the screw 3 (FIG. 1) for fastening the shaft so that the fan brake ring can not come into contact with the tapered brake ring (not shown) Cause the brake failure. Most of this failure occurred after lifting heavy objects, with a concealed, sudden,