Compound-Reibungsvakuumpumpe

摘要

The invention relates to a friction vacuum pump (1) comprising at least one turbomolecular pump stage, with a molecular pump stage that is subsequently connected on the pressure side, and with a transition stage mounted between the turbomolecular pump stage and the molecular pump stage. In order to improve the transition from the turbomolecular zone to the molecular zone, the transition stage has a flow section that is continuously tapered in the tangential direction.