Annular slave cylinder for motor vehicle clutch control mechanism

An apparatus for controllably operating a motor vehicle clutch, said apparatus comprising a hydraulic master cylinder, a hydraulic slave cylinder and a conduit interconnecting the master cylinder and the slave cylinder, said hydraulic slave cylinder being disposed concentric to an input shaft from said motor vehicle clutch to a gearbox, said slave cylinder comprising walls formed by a first tubular member disposed concentric to said shaft and a second tubular member spaced apart from said first tubular member and disposed concentric to said first tubular member, a clutch throw-out bearing disposed peripherally around said first tubular member, said throw-out bearing having an inner race and an outer race, an annular piston reciprocably disposed between the cylinder walls formed by said first tubular member and second tubular member, and a throw-out bearing carrier in the form of a sleeve slidably disposed around said first tubular member between said throw-out bearing and said piston, said sleeve having one end in engagement with said piston and another end forming a rim for mounting therein said throw-out bearing outer race, biasing means constantly urging said throw-out bearing longitudinally outwardly for engagement of said throw-out bearing inner race with a release mechanism for said clutch, a dust cover formed as a tubular member, an inwardly directed integral flange at one end of said dust cover having an edge in sliding engagement with the peripheral surface of said second tubular member, means attaching the other end of said dust cover to said throw-out bearing carrier for displacement of said dust cover in unison with said throw-out bearing, at least one lug outwardly projecting from the peripheral surface of said second tubular member for abutting engagement with said dust cover flange for limiting the outward displacement of said throw-out bearing by said biasing means, and an inwardly projecting indentation on said dust cover tubular member, said indentation extending longitudinally and preventing rotation of said dust cover through lateral engagement with said lug.