How does the overrunning clutch work?

The overrunning clutch can be divided into meshing type and friction type according to its working principle. The meshing overrunning clutch mainly includes ratchet, sliding pin and claw. Although the meshing clutch has a simple structure, it is generally used in low-speed situations because of its large impact and noise during meshing. The engagement of friction overrunning clutch is relatively stable and can be realized under any speed difference. Friction overrunning clutch is mainly divided into roller clutch, spring clutch and diagonal clutch.

Extended data:

Spring clutch is mainly composed of input shaft, output shaft, rectangular spring and guide shaft. The rectangular section coil spring of the clutch is installed between the input shaft and the output shaft. The radial dimensions of the two ends of the spring are large, forming an interference fit with the inner surfaces of the input shaft and the output shaft, while the radial dimensions of the middle part of the spring are small, forming a clearance fit with the inner surfaces of the input shaft and the output shaft.

The winding direction of the spring is determined. When the rotation direction of the input shaft is the same as that of the output shaft, and the rotation speed of the input shaft is faster than that of the output shaft, the spring expands radially outward due to the friction at both ends of the spring, so that the middle part of the spring is also close to the input shaft and the output shaft, so that the input shaft and the output shaft form a whole, and the clutch is in a transmission state at this time.

When the relative rotation directions of the input shaft and the output shaft are opposite, due to the action of friction, both ends of the spring contract radially, and there is a slip between the input shaft and the output shaft, and the clutch is in an overrunning state. At present, spring clutch has not been applied in China.