Two-stage clutch damper assembly

A two-stage clutch damper assembly for an automotive vehicle clutch driving a transmission input shaft, including a hub assembly having a barrel splined onto the input shaft and a radial flange having circumferentially spaced windows therein, a clutch plate carrying friction facings at the outer periphery thereof, a spring retainer plate secured to the clutch plate to sandwich the hub flange therebetween, said plates having circumferentially spaced windows therein axially aligned with said hub flange windows, and damper springs received in each set of windows, the improvement comprising a cam and detent arrangement between said clutch plate and hub including a generally cylindrical cam member splined onto said input shaft and having detent recesses formed in said forward face, and a retainer secured to said clutch plate and having circumferentially spaced ramps on its inner periphery conformably received in said detent recesses, said cam and hub having axially aligned facing pockets spaced circumferentially, and compression springs received in said pockets to bias the cam and hub apart, said hub flange windows extending circumferentially beyond said plate windows to allow limited rotation of the plates relative to said hub without compression of said damper springs, said cam and detent arrangement yieldably resisting said limited rotation.

A two-stage clutch damper assembly for an automotive vehicle clutch driving a transmission input shaft, including a hub assembly having a barrel splined onto the input shaft and a radial flange, a clutch plate carrying friction facings at the outer periphery thereof, a spring retainer plate secured to the clutch plate to sandwich said hub flange therebetween, said plates and hub flange having axially aligned sets of circumferentially spaced windows therein, and damper springs received in each set of windows, the improvement comprising a cam and ramp arrangement between said clutch plate and hub including a cylindrical cam splined onto said input shaft, axially aligned facing pockets formed in said cam and hub, and compression springs received in said pockets biasing said cam and hub apart, said hub flange windows extending circumferentially beyond said plate windows to allow limited rotation of said plates relative to said hub without compression of said damper springs, said cam and ramp arrangement yieldably resisting said limited rotation.