Why is the anti fall device also called a differential speed device

Fall arresters are important safety protection equipment for high-altitude operations, which can self lock in the moment of a fall, thereby avoiding the occurrence of falling accidents. Fall arresters also have a name called differential devices. Many people are not very familiar with the name differential devices. Today, Guanhang will take you to learn about the origin of the name differential devices.

Firstly, we need to understand how the differential completes self-locking. If we slowly pull out the wire rope from the casing of the differential, the entire process will be very smooth until the wire rope is fully pulled out. But if we quickly pull the steel wire rope, it will lock up within 500px, because sudden acceleration will cause the claws of the eccentric cam to be thrown out under centrifugal force and instantly engage with the teeth for self-locking.

This rapid tug represents the acceleration of a sudden fall during high-altitude operations, and this speed is significantly different from the speed at which the entire steel wire rope can be smoothly pulled out. This speed difference directly leads to completely different results, so the name "speed differential" has been widely used.