Variable displacement oil pump

Abstract

A variable displacement oil pump comprising a pump body, which oil pump is driven by a driven input shaft, a slide having an internal surface, the slide disposed in the pump body, the slide pivotally moveable by pressurization of a first chamber and second chamber, a rotor disposed for rotation within the slide, a plurality of vanes, each moveably disposed in a radial slot in the rotor, each radial slot in fluid communication with a vane fluid reservoir, wherein first and second pump body portions are disposed on the opposite sides of the slide and the rotor to hold each therebetween thus causing the volume defined by a pair of adjacent vanes to change to perform an oil suction and discharge, wherein the pump body portions comprise a suction region where a pump chamber undergoes a suction stroke, wherein the pump body portions comprise a discharge region where each pump chamber undergoes a discharge stroke and in which a fluid conduit is connected, the pump body portions each comprising a groove, each groove continuously communicating with each vane fluid reservoir, and the fluid conduit in the discharge region communicating with the first groove whereby a discharge pressure is continuously communicated to each vane fluid reservoir to urge each vane into continuous abutment against the slide.

I claim: 
     
         1 . A variable displacement oil pump comprising:
 a pump body, which oil pump is driven by a driven input shaft;   a slide having an internal surface, the slide disposed in the pump body;   the slide pivotally moveable by pressurization of a first chamber, a coil spring engaged with the slide resists movement of the slide;   a rotor disposed for rotation within the slide;   a plurality of vanes, each moveably disposed in a radial slot in the rotor, each radial slot in fluid communication with a vane fluid reservoir;   wherein first and second pump body portions are disposed on the opposite sides of the slide and the rotor to hold each therebetween thus causing the volume defined by a pair of adjacent vanes to change to perform an oil suction and discharge;   wherein the pump body portions comprise a suction region where a pump chamber undergoes a suction stroke;   wherein the pump body portions comprise a discharge region where each pump chamber undergoes a discharge stroke and in which a fluid conduit is connected;   the pump body portions each comprising a pump body fluid conduit, each fluid conduit in continuous communication with each vane fluid reservoir; and   a discharge fluid conduit in the discharge region communicating with the first fluid conduit whereby a discharge pressure is continuously communicated to each vane fluid reservoir to urge each vane into continuous abutment against the slide.   
     
     
         2 . The variable displacement oil pump as in  claim 1  further comprising:
 a second chamber for receiving a pressurization, wherein the first chamber and the second chamber are disposed between the pump body and the slide. 
 
     
     
         3 . The variable displacement oil pump as in  claim 1 , wherein all vane fluid reservoirs are each in simultaneous continuous communication with a pump discharge pressure for any position of the slide. 
     
     
         4 . The variable displacement oil pump as in  claim 1 , wherein each pump body fluid conduit comprises a groove.