Patent ID: 6835055
Filing Date: 2004-12-28
Classification: F01C,F04C

Abstract:
A vacuum pump of the rotary vane type comprising:a casing having a cylindrical inner wall surface; a first and a second end wall at opposite sides of said casing defining a fluid cavity therein; fluid inlet and outlet ports in open communication with said fluid cavity; a rotor extending between said end walls and fixedly carried by a drive shaft for rotation about an axis eccentric to said cylindrical inner wall surface, said rotor being provided with a plurality of longitudinally extending substantially radial slots about the periphery thereof; and a plurality of vanes, each being substantially radially slidably carried within a respective one of said slots, wherein at least one of said end walls and said rotor comprise, at oppositely facing surfaces, an annular recess and an annular rib, respectively, said rib and recess being interengaging so as to define a radial clearance and an axial seal, respectively, between said at least one of said end walls and said rotor; said rotor/drive shaft combination is rotatably mounted on said end walls via bearings provided between said rotor and said end walls; and said rotor/drive shaft combination is axially biased via axial stops provided on sides of said first and second end walls which face said fluid cavity, and a loaded spring mounted between said rotor and the axial stop provided on the side of one of said end walls.