Clubhead Vane Pump With Balanced Vanes

Abstract

The subject matter of this specification can be embodied in, among other things, a fluid pump that includes a housing with a cam block. The pump also includes a collection of vanes, each having a shank having a leading edge and a trailing edge, and a head having a curved outer side. The pump also includes a rotor having a collection of slots, each slot having substantially parallel leading and trailing edges spaced to accommodate the shank of one of the vanes, wherein each vane contacts the cam block at a contact point on the head controlled by the rotor slot position and the head outer curved surface, the contact point being located relative to the shank edge when the vane is radially aligned with the major and minor radii, and located rotationally to create a radial force between the head curved surface and the cam block.

What is claimed is: 
     
         1 . A fluid pump, comprising:
 a housing comprising:
 an inlet port and an outlet port; 
 a cam block having an inner surface comprised of two minor radii different from two major radii on the common center axis, and four developed curved surfaces connecting the two minor radii with the two major radii; 
   a plurality of vanes, each vane comprising:
 a vane shank having a leading shank edge and a trailing shank edge; and, 
 a vane head having a curved outer side, the curved side in contact with the cam block inner surface to separate a corresponding high fluid pressure region of a plurality of high pressure regions from a corresponding low pressure region of a plurality of low pressure regions; 
   a rotor having a central axis substantially aligned with the center axis of the cam block inner surface and comprising:
 a plurality of vane slots, each vane slot comprising:
 a leading slot edge; 
 a trailing slot edge substantially parallel to the leading slot edge, and spaced apart from the leading slot edge to accommodate the vane shank of one of the plurality of vanes; 
 a cavity at the radial inboard side of each slot forming a fluid path within the vane slot; and 
 
   fluid flow passages axially disposed on each side of the cam block with fluid passages communicating with the housing inlet and outlet ports and cavities formed by the cam inner surface, the rotor outside diameter and adjacent vanes and rotor cavities at the inboard side of each vane slot, wherein each vane of the plurality of vanes contacts the cam block inner surface at a contact point on the vane head controlled by the rotor vane slot position and the vane head outer curved surface, the contact point being located relative to the vane shank edge when the vane is radially aligned with the major radius and minor radius, and the contact point being located rotationally to create a controlled radial force between the vane head curved surface and the cam block inner surface.   
     
     
         2 . The fluid pump of  claim 1  wherein, for each vane of the plurality of vanes, the vane shank has a vane longitudinal axis that is offset from the central axis of the rotor. 
     
     
         3 . The fluid pump of  claim 1  wherein, for each vane of the plurality of vanes, the leading shank edge is substantially parallel to the leading slot edge when the vane is radially aligned with the minor radius, and the leading shank edge is tipped in the vane slot such that it is not parallel to the leading slot edge when the vane is radially aligned with the major radius. 
     
     
         4 . The fluid pump of  claim 3 , wherein an upper end of the vane shank is in contact with one of the leading slot edge or trailing slot edge, and a lower end of the vane shank is in contact with the other of the leading slot edge or the trailing slot edge. 
     
     
         5 . The fluid pump of  claim 1  wherein, for each vane of the plurality of vanes, the vane head extends away from the trailing shank edge at an angle substantially perpendicular to the trailing shank edge. 
     
     
         6 . The fluid pump of  claim 5 , the rotor further comprising a plurality of fluid ports, each of the plurality of fluid ports in fluid communication between a cavity of a vane slot and a high pressure fluid region of the plurality of high pressure regions, substantially adjacent to the cavity. 
     
     
         7 . The fluid pump of  claim 1 , wherein the curved outer side is generated from an axis located on the leading edge of the vane shank. 
     
     
         8 . The fluid pump of  claim 1 , wherein the leading slot edge is substantially in radial alignment with the central axis. 
     
     
         9 . The fluid pump of  claim 1 , wherein the curved outer side is generated from an axis offset a predetermined distance in a direction of rotation from the leading slot edge.