Clutch with slack take up and release motors

Claim 1

In combination with an automotive clutch of the type having confronting operating surfaces which are normally engaged, and which are disengaged upon movement of an associated throw-out bearing from an inactive to an active position, an actuator device comprising a clutch pedal normally disposed in an inactive position, and movable manually toward an active position, means including an operating rod normally holding said throw-out bearing in an inactive position , fluid power operated means controlled by said pedal for shifting said operating rod from a first to a second position to effect movement of said bearing from its inactive to its active position, and including a first member connected to said rod and movable, during the initial movement of said pedal toward its active position, a distance sufficient to shift said rod far enough toward its second position to take up any free play in the bearing holding means, and a second member releasably connected to said rod and operative during further movement of said pedal to its active position to move said rod fully to its second position thereby to place the throw-out bearing in its active position, control means operative, when said pedal has returned to its inactive position, initially to allow rapid return of said rod toward its first position, and then to slow down the rate of return of said rod as it approaches its first position, said first and second members comprising a pair of pistons mounted to reciprocate coaxially with said rod in a pair of spaced chambers, said rod being attaced to said bearing and to one of said pistons, means for selectively connecting said rod to the other of said pistons, and said fluid power operated means including valve means interposed between said clutch pedal and said chambers, and operable by said pedal selectively to connect said chambers to a fluid pressure source for imparting motion to said pistons, said valve means comprising a plurality or normally closed valves, means including a cam operable by said initial movement of said pedal to open one of said valves, thereby to connect the chamber containing said one piston to said pressure source to effect movement of said one piston and said rod in unison said distance sufficient to take up the free play in said bearing holding means, said cam being operable upon further movement of said pedal to open another of said valves to connect the other chamber containing said other piston to said pressure source to effect movement of said rod the remaining distance to its second position, and said connecting means comprising releasable coupling means in said other chamber operative releasably to secure said other piston to said rod during the reciprocation of said other piston thereby to impart the motion of said other piston to said rod.