
222 LIGHT AND HEAVY VEHICLE TECHNOLOGY
Fully centrifugal clutch
For clutches of this type, the engagement of the pressure
plate was effected by the action of bob-weights, each
pivoting from the clutch cover and acting in series with
a pair of helical control springs. The bob-weights were
carried on the free ends of bell-crank levers and swung
within clearance holes provided in the flywheel (Figure
13.27).
By limiting the outward travel of the bob-
weights, and hence the amount of force that could be
transmitted through the control springs, it was possible
to incorporate a clutch withdrawal mechanism of the
form normally associated with a conventiona ...