Air clutch with centrifugal force cancellation device

Claim 1

In an air clutch of the type having a rotatable drum positioned within a rotatable rim; an air bellows attached to the interior surface of said rim and expandable with the supply of compressed air to urge a plurality of friction blocks into contact with the exterior surface of said drums so as to cause said rim and drum to rotate as a unitary structure, each of said friction blocks being individually supported for radial movement by respective torque pins attached to said rim by means of restoring springs, and each of said friction blocks having a floor comprising an inner radially outwardly facing surface of said friction block; and a plurality of inertia means mounted on each of said torque pins for applying inwardly directed radial force to said friction blocks, the inertia means comprising: (a) first and second levers pivotably mounted at one end of said torque pin in crossed relation and symmetrical with respect to a radius of said rim; (b) third and fourth levers pivotably mounted at the other end of said torque pin in crossed relation and symmetrical with respect to a radius of said rim, each of said first through fourth levers having radially outer and radially inner ends; (c) a first inertia weight connected between the radial outer ends of said first and third levers; (d) a second inertia weight connected between the radial outer ends of said second and fourth levers; (e) a first contact member connected between the radial inner ends of said first and third levers; and (f) a second contact member connected between the radial inner ends of said second and fourth levers, said contact members being in abutment with the floor of said friction block whereby centrifugal force exerted on each of said inertia weights will result in the application of an inwardly directed radial force through said contact members to said friction block, which inwardly directed radial force is substantially equal and opposite to the centrifugal forces acting on said friction block due to the rotation of said rim.