1. Definition and principle

The key type differential shaft is called the key type differential shaft because of the structural characteristic that a movable key sheet or a movable key strip is arranged on the slip ring, and the key sheet or the key strip can be retracted or protruded along with the change of air pressure. The surface of the key sheet is not smooth, so friction is generated.

2. Structure

In addition to the different structure of the key bar, the other structure of the key differential shaft is different from the general XC type air expansion shaft. The key type differential shaft generally adopts central air pressure, locks the core roll and generates torque when ventilating, and can positively and negatively roll, automatically unload the roll, and has very high accuracy.