Rotational speed differential hydraulic clutch having control valves

A speed-difference-dependent hydraulic clutch, comprising a drive housing (27), which rotates in a housing (25) that is fixed in space and forms a reservoir for a working fluid, a hydrostatic displacement machine (35), which is accommodated in said drive housing, an output shaft (30), a friction clutch (36) for connecting the output shaft (30) to the drive housing (27) and a piston (5) for acting on the friction clutch (36), a pressure being produced in a pressure chamber (4) when a difference occurs between the speed of the drive housing (27) and that of the output shaft (30), this pressure giving rise to action upon the friction clutch (36), and the hydrostatic displacement machine (35) having a first (9) and a second (10) opening (9, 10) for the supply and discharge of working medium and a third (11) and fourth (12) opening (11, 12) for connection to the pressure chamber (4), wherein the first and the second opening (9, 10) are each connected in terms of flow to the reservoir (8), via a first and second rotary input (13, 14) and a first and second control valve (15, 16) respectively, said valves being fixed to the housing (25), the first and second control valve (15, 16) comprise controllable throttle valves, with the result that a control action takes place both at the respective supply side and at the discharge side of the displacement machine, irrespective of the direction of the differential speed.