Abstract: The present invention pertains to a dry-running screw compressor, in which the suction-side bearing housing and the pressure-side bearing housing are provided on the inside with journals for engaging holes in the rotors. The two rotors within the compressor housing include only the body of the ribbed rotor and grooved rotor, and the journals of the rotors, which are located on the outside for mounting, are eliminated. The rotors are mounted on the pressure-side journals by means of radial and thrust bearings which are secured by corrugated nuts. Only radial bearings are used on the suction-side journals. The sealing between the tooth spaces of the rotors is ensured by means of sealing disks. To maintain the distance between the rotor faces, gearwheels are inserted on the pressure side between the sealing housing and the bearing housing. The ribbed rotor is driven in this exemplary embodiment with a coupling half for the drive via a torsion shaft.

Abstract: In a shaft seal having a radial plane seal ring gap and comprising a seal ring rotating with a shaft, and a non-rotating seal ring mounted on a housing of the seal through an element which is elastically yielding in every direction and serves as a packing at the same time, the sealing fluid flows into the sealing gap through supply bores and through associated distributing pockets which are provided in the non-rotating seal ring and/or at the outer or inner circumference of the rotating seal ring. Sensors for measuring the sealing gap are provided in the non-rotating seal ring on the gap side. By means of the measured values, electromagnets disposed in the seal housing to face each other and cooperating with opposite magnetizable bodies provided in the non-rotating seal ring, are electronically controlled to maintain a predetermined constant small width of the seal gap.