Abstract: A torque limiting coupling contains a first shaft, a second shaft and a coupling ring. The coupling ring contains a coupling sleeve with an inner surface and an outer surface. The coupling sleeve is arranged in the radial direction between the first shaft and the second shaft, such that the inner surface is in frictional contact with the first shaft and the outer surface is in frictional contact with the second shaft. The coupling sleeve is double-walled with an internal annular pressure oil chamber, configured in such a way, that the coupling sleeve increases its radial thickness when the oil chamber is filled with pressurized oil and thereby increases the pressure forces and thereby the friction between the surfaces and the shafts in order to allow torque transfer between the two shafts, and that the coupling sleeve transfers no torque, when the oil chamber is not filled with pressurized oil.

Abstract: A torque limiting coupling has a shaft, a shear plate fixedly connected to the shaft, and a coaxially disposed coupling ring. The coupling ring has a lateral surface in contact with the shaft and a double-walled section with an internal annular pressure fluid chamber. When the fluid chamber is filled with pressurized fluid, the radial thickness increases and increases the pressure and friction forces for a torque transfer between the coupling ring and the shaft. A shear tube closes the pressurized fluid chamber. A shear plate is configured to cut off a tip of the shear tube in order to open the pressure fluid chamber when the first shaft slips relative to the coupling ring. A central bolt affixes the shear plate to the shaft by pressing a conical bushing of the shear plate onto a conical connector of the shaft.