Patent ID: 8708678

Claim:
A gear pump, comprising: a central housing having a suction side, a discharge side, a housing top flange and a housing bottom flange; a drive gear assembly disposed in the central housing, the drive gear assembly comprising a drive shaft having a plurality of first gear flights extending therefrom; an idler gear assembly disposed in the central housing in operative relation to the drive gear assembly, the idler gear assembly comprising an idler shaft having a plurality of second gear flights and a fluid pathway; a first bearing having a pair of openings defined therein, the openings capable of receiving the drive shaft and idler shaft; a second bearing having a pair of openings defined therein, the openings capable of receiving the drive shaft and idler shaft; a gear insert disposed in the central housing, between the first and second bearings, and sized to fit over the plurality of first and second gear flights, the gear insert having an inner wall disposed in spaced apart relation to the plurality of first and second gear flights; a cover attached to the housing top flange of the central housing and enclosing the drive and idler gear assemblies; an adapter spool having a central opening for receiving a containment can, the adapter spool having a spool top flange and a spool bottom flange, the spool top flange capable of mating with the housing bottom flange of the central housing; a drive magnet assembly disposed in the adaptor spool; a driven magnet assembly disposed in the containment can in operative relation to the drive magnet assembly; and, an electric motor coupled to the drive magnet assembly; an O-ring disposed between the second bearing and the cover; wherein the first bearing, the second bearing, and the gear insert define a pump chamber for pumping fluid therethrough; wherein an increase in fluid pressure in the pump chamber increases a fluid force applied against the second bearing, toward the pump chamber and a fluid force applied against the first bearing, toward the pump chamber; wherein the fluid pathway is configured to balance the fluid force applied against the second bearing, toward the pump chamber and the fluid force applied against the first bearing, toward the pump chamber.