| 摘要 |
1. A vehicle disc brake, more particularly a motor vehicle disc brake, of the type comprising a yoke (1) straddling the disc (2), on either side of which are provided friction linings (3) adapted to be applied against it by at least one hollow piston (4) mounted to slide in a cylinder (5) connected to the yoke, either in response to a hydraulic pressure in the cylinder or in response to manual mechanical control ; a mechanism for automatic take-up of the play produced by the wear of the friction linings, said mechanism being disposed inside the piston and comprising a tapped bush (11) fitted on a screwthreaded rod (9) and adapted to be driven by the piston, a washer (14) being provided on the piston to move the tapped bush (11) and defining a chamber (27) between itself and the end of the interior (4b) of the piston (4) ; means (G) for bringing into communication the two spaces situated on either side of said washer (14) to facilitate bleeding of said chamber (27) ; and support means (R) adapted to be disposed inside the piston (4) so that the tapped bush (11) may come into contact with said support means (R) when it is urged by the screwthreaded rod (9) and drives the piston (4) ; characterised in that the said communication establishing means (G) comprise at least one axial slot (28) provided in the inner wall of the piston and extending axially on either side of the washer (14), and in that said support means (R) are in the form of a cylindrical member (29) one surface (29a) of which is disposed against the end of the interior (4b) of the piston while the other surface (29b) is adapted to come into contact with the tapped bush (11), the said cylindrical member (29) having, on the one hand, a central aperture (31) in which the screwthreaded rod (9) engages and, on the other hand, radial slots (32) leading into additional slots (33) in the outer surface of the cylindrical member (29) to provide effective bleeding of the internal volume of said cylindrical member (29). |
