Block brakes can be divided into short-stroke brakes an […]
Block brakes can be divided into short-stroke brakes and long-stroke brakes according to the length of the release stroke.
How short stroke brakes work
When the mechanism is powered off, the main spring pushes the rod 2 outwards, and the frame rod 5 moves inwards, pulling the left and right brake arms 3, 8 to press the brake pads 12, 9 against the brake wheel 11. The frictional torque generated between the brake shoe and the brake wheel causes the mechanism to brake. When the mechanism is energized, the armature of the electromagnet 1 is attracted to the core. drum brake The armature pushes the push rod 2 to the right to further compress the main spring 4. At this time, the left brake arm 13 automatically tilts leftward under the eccentric pressure generated by the weight of the electromagnet, so that the left brake pad 12 leaves the brake wheel 11, left When the brake arm 13 is deflected to the position of the adjusting bolt 10, the brake arm 13 is blocked and stopped. At the same time, the sub-spring 6 causes the right brake arm to drive the right brake pad 9 to tilt rightward to move away from the brake wheel to realize a loose brake. The short-stroke brake has the advantages of loose brake and rapid on-gate brake, small size, light weight, uniform contact between the brake wheel and the pad, and easy adjustment. However, due to the limitation of the electromagnet suction force, it is generally used in the case of small braking torque and braking. Wheel diameter is less than 300mm in the body.
Long stroke brake operation
Because the short stroke brake is limited by the attraction force of the electromagnet, a large braking torque cannot be obtained. Therefore, the brake torque mechanism uses a long-stroke electromagnetic pad brake. The long stroke brake is also dependent on the main spring brake and the electromagnet is loose, but because the electromagnet can increase the brake force through the lever system, a larger braking torque can be obtained.
The advantage of the electromagnetic tile type brake is that it is simple in structure and can be interlocked with the operating circuit of the motor. Therefore, when the motor stops working or suddenly loses power, the brake can be automatically opened and the work Auto accessories is safe and reliable. However, due to the violent impact of the electromagnet during the operation (short-stroke brake is particularly severe), the noise is very loud, and the violent braking will have an adverse effect on the mechanism, and at the same time, the electromagnet constantly makes the electromagnet continuously start and brake. Collisions result in low life and require frequent servicing. Therefore, lifting mechanisms generally use three-phase AC long stroke brakes more reliable.