Transmission device with a controlled viscous coupler, in particular for a motor vehicle

Abstract

The invention relates to a transmission device between two coaxial rotating members (1; 10), of the type comprising a viscous-fluid coupling (11) with a driving element and a driven element, and control devices for modifying the operating characteristic of this coupling. It is defined, in particular, in that the control devices are incorporated into the transmission device and act as a function of the rotational speed of one the said members and as a function of a torque transmitted by the device. The control devices can comprise flyweights (21) which are rotationally integral with the member (1) and with the case (12) of the viscous-fluid coupling, these flyweights acting to modify the internal pressure in the coupling (11), via shuttles (27) and a sliding sleeve (8) which is displaced as a function of the torque transmitted between the sun gear (2) and the output shaft (10). This sliding sleeve can, for example, act on a plate (16) which modifies the spacing between the disks (14, 15) of the coupling. Application, in particular, to four-wheel drive vehicles.

Dependencies are inferred from the claim text.