Rubber/viscous torsional vibration dampers

Claim 1

A tuned rubber/viscous torsional vibration damper assembly having supporting rotor disk means with a radially outwardly extending circular body and a radially inner hub portion adapted to be secured to a rotary member such as a crankshaft subject to vibrations to be damped by the damper, said body being located concentrically within a radially inwardly opening annular working chamber of an annular inertia mass, said body dividing said working chamber into axially opposite sides, a viscous damping medium in each opposite side of said chamber between shear film spaced cooperatively confronting working surfaces of said body and said inertia mass, and said inertia mass having concentric annular grooves at opposite sides and facing axially toward said body radially inwardly adjacent to the opening from said chamber, there being elastic tuning spring, spacing and sealing rubber rings coupling surface areas on said inertia mass in said grooves with opposing surface areas on said body, comprising: a circumferentially spaced plurality of rubber fingers extending radially from said rubber rings and secured fixedly to certain of said working surfaces in each axial side of said working chamber; said fingers being of a thickness less than the shear film space between said working surfaces in each side of said working chamber, and functioning as spacers or bumpers to prevent direct contact between said working surfaces in the event of axial load or displacement forces tending to move said rotor disk and said inertia mass axially relative to one another; an annular series of spaced apertures through said surface areas of said inertia mass; integral lugs on said rings and filling said apertures; said rubber rings having portions thereof exposed at the outside of said inertia mass; and a rubber skin coating outside areas of said inertia mass and connected to said exposed areas of said rings.