DISPOSITIF D'ACCOUPLEMENT A ENTRAINEMENT PAR FRICTION, POUR RELIER DEUX PARTIES AMOVIBLES ET LES RENDRE SOLIDAIRES EN ROTATION, PAR EXEMPLE UN MOYEU ET UN ARBRE

The invention relates to a frictional resistance coupling for transmitting torque between two coaxial components, for example a shaft with an articulated shaft, the coupling comprises an outer part and an inner part, which enclose an inner chamber with a conical wall. Inserted to move axially in the inner chamber is an annular piston of the same conicity, so that when the annular piston moves axially by means of a pressure medium, a radial clamping force and thus frictional resistance for transmitting torque is produced. The pressure chambers located on both sides of the annular piston in each case comprise a further connection to a low pressure source. The pressure chamber respectively not supplied with high pressure is supplied with pressure medium from a low pressure source during the displacement process and when the piston reaches the end position within the inner chamber, the opening of the low pressure passage is closed by the end face of the piston. Thereupon a higher pressure builds up in the low pressure supply line and a sensor apparatus emits a signal at the time of a corresponding pressure, which is an indication that the annular piston has definitively reached its end position. The apparatus according to the invention should increase the safety against slipping, which is of great signficance particularly in the construction of heavy machines.