Advantages and disadvantages of elevator block brakes and disc brakes

Advantages and disadvantages of elevator block brakes and disc brakes
Compared with drum brakes, the advantages of block brakes and disc brakes: compact structure, small stroke, and low cost.
Compared with drum brakes, the disadvantages of block brakes and disc brakes are as follows.

(1) The braking torque cannot be adjusted. After the design and selection, the braking torque is already a fixed value, which cannot be adjusted again after leaving the factory, and the matchability in field use is poor.
(2) The working stroke is small, and the sensitivity of the stroke micro switch is high, which may easily cause false alarms of the detection signal.
(3) The remaining stroke of the design is small. After the friction plate is worn out, it is not easy to adjust the gap between the dynamic and static armatures on the whole machine after the gap exceeds the rated value. Basically, it adopts a one-time design and can only be replaced to meet the whole life cycle of the traction machine. The cycle cost is high.
(4) On-site installation, adjustment, inspection and maintenance are difficult, and the gap consistency is relatively poor. It is difficult for general maintenance personnel to master, and professionally trained personnel are required to operate.
(5) The input voltage stability requirement is high. Voltage instability will cause the armature to lift abnormally (such as partial suction), resulting in operation with the brake. Generally, the pressure reduction is not used, and the temperature rise is high; in the hot state, there is a potential risk of insufficient electromagnet suction.
(6) The gap between the dynamic and static armatures is large, and various foreign objects are easy to enter between the dynamic and static armatures, and the potential risk of jamming is high.
(7) The buffer pad is built-in, which is easy to age and is not easy to replace.
(8) The friction disc of the commonly used disc brake is made of light aluminum alloy non-magnetic material, which is connected with the sliding key shaft made of carbon steel through the inner teeth, and the inner teeth of the friction disc are easy to wear and fail. Therefore, it can generally only be used in elevators with lower speeds and lower buildings.