Abstract: A torsion damping device comprising guide rings, a damper plate, and a hub which is secured to a driven shaft for rotation of the latter therewith. The device includes a dynamic vibration damper attached to the hub, with this damper including a weight which is joined through a block of elastic material to a support. This support in turn is joined to the hub for rotation with the latter after a clearance has been taken up.

Abstract: The invention provides a transmission between a power input and an output shaft, especially suitable for a motor vehicle. The transmission incorporates a speed variator and a planetary device with four elements. The planetary device comprises two planetary gears connected to one another and coupled to the power input by means of the variator, a satellite-holder adapted to be braked so as to obtain reverse motion, an output element formed by the ring and the satellite-holder, and a ring which is designed to be either left idle or, for example, braked so as to obtain two ranges of forward motion. The primary pulley of the variator is coaxial with the axis of the power input, while the secondary pulley of the variator is coaxial with the planetary device. The variator and the planetary device are located in two separate enclosures of the housing.