Torsion-keyed vibration damper

Claim 1

A VIBRATION DAMPER FOR THE ROTATABLE CRANKSHAFT OF AN ENGINE COMPRISING A FIRST MEMBER ADAPTED TO BE COUPLED TO A CRANKSHAFT FOR ROTATION WITH THE LATTER, A SECOND MEMBER OF PREDETERMINED INERTIA MASS TO DAMPEN CRANKSHAFT VIBRATIONS, SAID MEMBERS RESPECTIVELY INCLUDING RADIALLY SPACED OPPOSED ANNULAR FRICTIONAL DRIVE SURFACES AND A PLURALITY OF RADIALLY OPPOSED ANNULARLY SPACED PARTI-CYLINDRICAL DRIVE POCKETS, AND UNITARY RESILIENT MEANS COMPRISING A SLEEVE-LIKE BODY AND A PLURALITY OF SPACED NODULES PROJECTING RADIALLY THEREFROM, SAID BODY INCLUDING SAID NODULES BEING RESPECTIVELY RADIALLY COMPRESSED BETWEEN SAID SURFACES AND RADIALLY OPPOSED PAIRS OF SAID POCKETS, WHEREBY SAID RESILIENT MEANS PERMITS SAID MEMBERS TO OSCILLATE TO A LIMITED EXTENT RELATIVE TO EACH OTHER AS THEY ROTATE WITH A CRANKSHAFT TO DAMPEN VIBRATIONS IN THE LATTER WHILE SAID NODULES RESILIENTLY KEY SAID MEMBERS AGAINST PERMANENT RELATIVE ANGULAR DISPLACEMENT.