Mechanism incorporating a vibration damper, in particular for an automative vehicle

Claim 1

A transmission mechanism for an automotive vehicle comprising a vibration damper and a fluid lubricated gearbox including a gearbox shaft, a gearbox pinion, and an axle, the vibration damper comprising a double inverter pinion and means mounting the double inverter pinion rotatably on said axle, the double inverter pinion being divided into two separate pinions, namely a first pinion and a second pinion, one of said first and second pinions mounting the other coaxially thereon for relative rotational movement of one of said pinions with respect to the other, said first pinion fixedly carrying a first group of fins and the second pinion fixedly carrying a second group of fins, said fins extending generally in radial planes with any one fin of a group being interposed circumferentially between two fins of the other group to define limits of predetermined angular displacement between said first and second pinions, the vibration damper further including resilient means operatively interposed between said groups of fins to resist said angular movement, said vibration damper being defined within the double inverter pinion in the gearbox, with one of said first and second pinions being arranged to be coupled in rotation with said gearbox shaft and the other being arranged to mesh with said gearbox pinion, wherein said resilient means comprise a plurality of resilient members, each interposed circumferentially between a fin of one said group and a fin of the other said group, there being fewer of said resilient members than of the fins in total, whereby between two consecutive fins of one group, there is at least one chamber from which said resilient members are absent.