Gerotor pump or motor device with rolling support

Abstract

A gerotor or pump or gear device includes a stationary housing having a chamber with an outer ring gear and inner rotor. The outer ring gear is supported by rolling elements between the housing and outer ring gear and is rotatable about a center axis. The inner rotor is fixed to a shaft and rotatable therewith about a shaft axis that is offset or eccentric relative to the central outer ring gear axis.

What is claimed is: 
     
         1 . A gerotor pump or motor device, comprising:
 a stationary housing having an inner chamber;   an outer ring gear disposed within the chamber and rotatable relative to the housing about a center axis A, the outer ring gear having a plurality of inner gear teeth;   a shaft;   an inner rotor mounted on the shaft, the shaft and the rotor being supported by the housing for rotation about a shaft axis B that is offset relative to the center axis, the inner rotor having a plurality of outer teeth that engage the inner teeth of the outer ring gear;   and wherein the rotatable support for the outer ring gear is provided by a plurality of rolling elements disposed between the housing and outer ring gear.   
     
     
         2 . The device of  claim 1  wherein the rolling elements comprise either roller bearings, needle bearings or ball bearings.