Patent ID: 6022202
Filing Date: 2000-02-08
Classification: F01C,F04C

Abstract:
A vacuum pump with a circular translation cycle, comprising:a stationary body including at least one stationary disc which has on one face a first spiral-shaped projection;a moveable disk facing the stationary disk and having at least one second spiral-shaped projection interleaved with the first spiral-shaped projection of the stationary disk and with the same angular range;first teeth attached to the moveable disk;a mechanism by which the moveable disk is connected to said body and supported by it, for driving circular translational motion of the moveable disk relative to said body during operation of the vacuum pump;a pump shaft;actuating means for driving the moveable disk by means of the pump shaft so that it effects the circular translation movement;a device for limiting relative circular translational movement;said mechanism comprising at least one bush carried by the pump shaft;said circular translational movement limiter device comprising a ring having stationary teeth between which the first teeth attached to the moveable disc are interleaved;wherein the stationary teeth are limited by cylindrical surfaces with axes parallel to a stationary axis of the vacuum pump and the section of which in a plane perpendicular to the stationary axis is composed of first and second circular arcs of radius R and r, respectively, the centers of which are on a circle of radius R.sub.p centered on the stationary axis, the first arcs lying inside said circle and the second arcs lying outside said circle, andwherein R and r are not the same radius and wherein the centers of the first and second arcs are circumferentially offset from each other on the circle.