Suco F-Type Centrifugal Clutch. The compact design and self-increasing effect allow this clutch to transmit remarkably high torques while needing very little space, resulting in a performance factor of ca. 2.5.
Because the tension springs are easily accessible and the linings removable, the parts subject to wear are easy to replace. Because the linings are not secured to the flyweights, some noise is possible in service, but normally not sufficient to cause a nuisance.
Self-increasing effect: the profiled hub has a special form which causes a wedging effect between the profile and the flyweights when torque is applied to the clutch. This results in an additional force on the linings and allows a higher torque to be transmitted.
The flyweights (2) are seated on the profiled hub (1) and are held against it by tension springs (3), which are hooked into the linings (4). Discs locate the flyweights axially. Each lining has a crimping on its inner surface to locate it on the flyweight. This prevents the linings from moving sideways.
As the profiled hub rotates, the centrifugal force acting on the flyweights overcomes the spring force. When the speed is high enough, the linings contact the clutch drum (5), and friction between the linings and the drum allows torque to be transmitted between the two.