Expanding friction disk configurable to be compatible with wear liners and improved friction disks

Abstract

An improved expanding friction disk for use in a clutch of a power transmission system. The improved expanding friction disk accommodates multiple clutch pack configurations including clutch packs utilizing novel improved friction disks, is compatible with wear liners and operates with reduced friction including a reduced difference between the static and dynamic coefficients of friction in the ramp mechanism.

I claim: 
     
         1 . A clutch assembly for a vehicle, comprising:
 a generally cylindrical clutch basket with sidewalls, a closed first end and an open second end, with said sidewalls made up of fingers and slots between the fingers;   a plurality of wear liners disposed in each slot, said slot liners lining the sides and bottom edges of said sidewall fingers, to prevent contact between said fingers and positioning tabs of friction plates, and with said wear liners further comprising a capture flange on each side piece of said wear liner;   a plurality of driving friction disks mounted in said clutch basket, each driving friction disk comprising a circular and planar disk with a hollow center portion, with a plurality of positioning tabs extending out from a periphery of each driving friction disks, configured to extend between said fingers, and each driving friction disks configured for frictional engagement with an adjacent driven friction disk;   a plurality of driven friction disks mounted in said clutch basket, each driven friction disk comprising a circular and planar disk with a hollow center portion, with a plurality of engagement tabs extending toward the center of said disks, for engagement with a center clutch which is configured to rotate in relation to said clutch basket, with each driven friction disks configured for frictional engagement with an adjacent driving friction disk; and   an expandable friction disk interleaved in said plurality of friction disks, said expandable disk configured to become thicker through rolling contact between a pin a first and second plate and at least one centrifugal actuating members, with said centrifugal actuating member configured to move when subjected to a selected amount of centrifugal force and said expandable disk configured to become thinner when said centrifugal force decreases, with said plates and centrifugal actuating members moving over each other by rolling engagement of one or more pins captured between said ramps and said ramp sockets.   
     
     
         2 . The clutch assembly of  claim 1  in which said expandable disk further comprises a generally planar and circular first plate with an inner and an outer surface, with said first plate inner surface defining at least one generally rectangular ramp, said ramp having a ramped bottom surface, with said ramp being deepest toward the center of the circular first plate, and less deep toward the periphery of said circular first plate, with said ramp oriented transverse to a radial line from the center of said circular first plate;
 a plurality of centrifugal actuating members adjacent to said first plate, with said centrifugal actuating members having a first side and a second side, with said first side defining at least one pin socket configured for receiving a cylindrical pin in each centrifugal actuating member; and 
 a generally planar and circular second plate with an inner and an outer surface, with said second plate inner surface facing said plurality of centrifugal actuating members; 
 with said first and second plates attached and pressed together by a plurality of springs, and with said plurality of centrifugal actuating members configured to move by centrifugal force in a radial direction toward the periphery of said first and second plates, with said plurality of springs urging said plates closer to each other by pressing said cylindrical pin into send deeper region of said ramp, and with said plates configured to move apart due to centrifugal force pressing said centrifugal actuating members toward a periphery of said disks and thus causing said cylindrical pins to move into a less deep portion of said ramp.