Pump Assembly

Abstract

A pump assembly, which comprises at least one housing and two gear wheels as transfer means as well as a drive shaft. The housing comprises at least one base and one cover element, which can be connected together in order to constitute a pressure chamber. Each of the two gear wheels has a toothing on an outer circumferential surface and mesh with one another via the toothing in order to transfer a fluid. The gear wheels are arranged in an axial direction between the base and the cover element in the pressure chamber. The drive shaft extends into the housing in the axial direction via an opening in the cover element. The first gear wheel is arranged on a first bearing bush, wherein the first bearing bush is mounted only in the base. The first gear wheel is connected to the drive shaft via a formfitting connection in a circumferential direction.

1 . A pump assembly, comprising
 one housing having at least one base and one cover element, which can be connected together in order to constitute a pressure chamber;   two gear wheels, which respectively have a toothing on an outer circumferential surface and mesh with one another via the toothing in order to transfer a fluid; wherein the gear wheels are arranged in an axial direction between the base and the cover element in the pressure chamber; and   a drive shaft, which extends into the housing in the axial direction through an opening in the cover element;   
       wherein at least a first gear wheel is capable of being driven as an input gear wheel by the drive shaft; wherein at least the first gear wheel is embodied as a ring gear, wherein the first gear wheel is arranged on a first bearing bush, wherein the first bearing bush is mounted only in the base; wherein the first gear wheel is connected to the drive shaft via a formfitting connection in a circumferential direction. 
     
     
         2 . The pump assembly as claimed in  claim 1 , wherein the drive shaft is arranged in a radial direction with a free clearance with respect to the first gear wheel and the first bearing bush. 
     
     
         3 . The pump assembly as claimed in  claim 1 , wherein the drive shaft is arranged mounted exclusively outside the housing with respect to a force acting in a radial direction. 
     
     
         4 . The pump assembly as claimed in  claim 1 , wherein the formfitting connection is constituted by an inner circumferential surface of the first gear wheel and an outer circumferential surface of the drive shaft. 
     
     
         5 . The pump assembly as claimed in  claim 1 , wherein the drive shaft and the first gear wheel or the drive shaft and the first bearing bush constitute an abutment against displacement in the axial directions. 
     
     
         6 . The pump assembly as claimed in  claim 1 , wherein the first bearing bush is connected to the base via a press fit. 
     
     
         7 . The pump assembly as claimed in  claim 1 , wherein the first bearing bush is connected in an integrally bonded manner to and formed integrally with the base. 
     
     
         8 . The pump assembly as claimed in  claim 1 , wherein at least the base and the cover element are embodied at least partially as sintered parts. 
     
     
         9 . The pump assembly as claimed in  claim 1 , wherein at least the first bearing bush is embodied as a sintered part. 
     
     
         10 . The pump assembly as claimed in  claim 1 , wherein the second gear wheel is also embodied as a ring gear, wherein the second gear wheel is arranged on a second bearing bush, wherein the second bearing bush is mounted only in one or other of the base and the cover element.