situated at a diameter which also is somewhat smaller than the diameter of the circle corresponding to the hole area 40 of the screw thread rotor consequently superatmospheric pressure in the pressure chamber 26 will result therein that the rolling bearing 7 of the screw thread rotor 8 9 is exposed to an axial force which constantly acts in the direction of the arrow 42 through exact mounting of the rolling bearings the play between the rotors during operation is hereby kept very low if needed it is possible to allow the outer races of the rolling bearings 6 7 to be freely glidable and axially unlocked by stops in the housing parts 1 2 so that the screw thread rotor 8 9 may adjust itself in relation to the flanks of the screw cam means on the screw cam rotor 19 20 and the leap plane 25 of the rotors since the area of the balancing piston 29 and the area of the neck of shaft 13 situated inside the circumferential groove 36 both are close to the hole area 40 the axial forces in the arrow directions 39 and 42 become low so that the screw cam rotor 19 20 can be driven with high numbers of revolution without overloading the rolling bearings of these the bearings 17 18 in the present compressor application work with a number of revolutions on the screw cam rotor 19.