Centrifugal Clutches & Brakes - F-type Self-increasing Centrifugal Clutch

By Norman G. Clark

Norman G. Clark - Centrifugal clutches and brakes are used when input and output side should be separated during a standstill and the output side should work speed-dependant.

Advantages of centrifugal clutches are load-free starting and slip-free torque transmission at operating speed. Centrifugal brakes are often used as emergency braking system. They can lower or slow down loads at a defined speed.

The most important factor for selection of a centrifugal clutch is the amount of power to be transmitted. Knowing the power available from the drive motor and the operating speed, the torque to be transmitted can be calculated and the size of the clutch determined.

For the vast majority of drives, there is a wide range of clutch types and designs. Our sizes 01 to 13 cover – depending on engagement and operating speeds – a torque range up to ca. 2000 Nm.


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.

Construction and mode of operation

The flyweights (2) are seated on the profi led 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.