Clutch

#The invention relates to a clutch having at least one friction lining, provided between a disk arranged in a rotationally secure fashion on a first shaft and a pressure plate arranged in a rotationally secure and axially displaceable fashion on a second shaft, for producing a grip between the disk and the pressure plate, having an actuating mechanism for moving the pressure plate against the force of a spring element which biases the pressure plate in the direction of the disk, and having a sensor device for detecting the limit of wear of the friction lining.

#Clutches are frequently arranged in present-day motor vehicles between an internal-combustion engine and a transmission, and are therefore known. The disk is in this case frequently constructed as a flywheel disk and fastened on a drive shaft of the internal-combustion engine. When the limit of wear is reached, the friction lining has a minimum thickness and must be exchanged.

#A brake known in practice has an electric conductor, through which a signal current flows, in a friction lining in the region of the limit of wear. When the limit of wear of the friction lining is reached, the electric conductor is severed and the signal current is interrupted. The interruption of the signal current thus signals that the minimum thickness of the friction lining has been reached.

#While the present invention is capable of embodiment in various forms, there is shown in the drawings and will be hereinafter described a presently preferred embodiment with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiment described and illustrated.

#FIG. 1 shows, in a longitudinal section, a diagrammatic representation of half of a clutch according to the invention, which has a clutch bell 1 forming a housing. The clutch has a flywheel disk 3, which is arranged on a drive shaft 2 in a fashion which is rotationally secure and cannot be displaced axially, and a pressure plate 5, which is arranged in a fashion which is rotationally secure and axially displaceable on an output shaft 4 constructed as a splined shaft. Friction linings 6 for producing a grip between the pressure plate 5 and the flywheel disk 3 are arranged between the pressure plate 5 and the flywheel disk 3. For this purpose, the pressure plate 5 is biased by means of spring elements (not represented) against the flywheel disk 3. An actuating mechanism 8 is provided on the side of the pressure plate 5 averted from the flywheel disk 3 for the purpose of removing the pressure plate 5 from the flywheel disk 3. The actuating mechanism 8 is arranged in a clutch cover 9 permanently connected to the output shaft 4. In the case of wear of the friction linings 6, the pressure plate 5 moves in the direction of the flywheel disk 3 until a limit of wear of the friction linings 6 is reached. This limit of wear defines the minimum thickness of the friction linings 6 at which the clutch operates reliably. This position is illustrated in the drawing by dashed and dotted lines.

#The clutch has a sensor device 7 with an electric switch 11 for generating an electric signal when the limit of wear of the friction linings 6 is reached. The switch 11 is fastened in an opening 10 in the clutch bell 1, and has an electric sensor conductor 13 connected in series with an electric resistor 12. A switching part 14 is mounted rotatably on the clutch cover 9. The switching part 14 is held in a radially inner position by a blocking part 15 pressed into the pressure plate 5. Furthermore, the switching part 14 is biased by a spiral spring element 16 against the blocking part 15.