Vane Pump with Moveable Sleeve

Abstract

A vane pump including a movable sleeve disposed between the casing and the rotor vanes in which axial and angular movement of the sleeve enables control of the fluid flow.

1 . A vane pump comprising:
 a casing;   a rotor disposed in said casing, said rotor including vanes; and   a sleeve disposed about said rotor and movably within said casing, said sleeve including a plurality of circulation channels and a plurality of apertures, said apertures having their ends slanted relative to said vanes.   
   
   
       2 . A vane pump as set forth in  claim 1  wherein a plurality of end stops abut said rotor. 
   
   
       3 . A vane pump as set forth in  claim 1  wherein a plurality of supports abut said rotor. 
   
   
       4 . A vane pump, comprising a casing, a rotor with vanes and shaft, two lids, two end stops, two supports, and a sleeve disposed about said rotor and within said casing, said sleeve and said casing together defining a plurality of circulation channels therebetween, said casing having a plurality of apertures, said apertures having slanted ends, said sleeve being movable relative to said casing to place said ends of said apertures in variable relation to said circulation channels.