Speed change device pulley with a seal around the hub

Claim 1

Variable speed drive pulley of the kind comprising a hub which has an internal opening and, in face-to-face relationship to each other around said hub, two annular flanges of which at least one, hereafter referred to for convenience as the mobile flange, is mounted so as to be mobile axially relative to said hub being for this purpose axially fastened to a bush slidably engaged on the latter with, disposed between said bush and said hub, two pads of anti-friction material axially spaced from each other, in association with a spacer, hereinafter referred to for convenience as the abutment space, which is also fastened axially to the mobile flange and adapted to limit its axial displacement in one direction, and in association with a regulating chamber which, adapted to be connected to a source of fluid, is defined at least in part by the mobile flange, the hub and a seal disposed around said hub in line with said abutment spacer and linked to move with said mobile flange, this variable speed drive pulley being characterized, in combination, on the one hand in that the abutment spacer is carried by the end of the bush of the mobile flange directed towards the fixed flange and it features, transversely, a collar which is directed radially towards the axis of the assembly and by virtue of which it delimits, for its part, a housing in which is disposed the associated seal, and, on the other hand, in that for the purpose of connecting the regulating chamber to a source of fluid there is provided in the bush between the anti-friction material pads at least one passage and, in the hub, also between said anti-friction material pads, for communication between the internal space of the hub and the volume delimited by the anti-friction material pad between it and the bush, at least one passage.