Pump Assembly

Abstract

Disclosed is a pump assembly ( 1 ) at least comprising a pump ( 2 ) having a discharge side ( 3 ) and a suction side ( 4 ), and a drive unit ( 5 ) for the pump ( 2 ), the pump ( 2 ) and the drive unit ( 5 ) being arranged in a common housing ( 6 ), the drive unit ( 5 ) being an axial-flow electric drive comprising a stator ( 7 ), which is rotationally fixedly connected to the housing ( 6 ), and a rotor ( 8 ), which is rotatably arranged relative to the housing ( 6 ), a first end face ( 9 ) of the rotor ( 8 ) being oriented towards the stator ( 7 ) along an axial direction ( 10 ), the rotor ( 8 ) forming an outer pumping means ( 11 ) of the pump ( 2 ) and having a first pumping profile ( 13 ) on an inner circumferential surface ( 12 ); in a radial direction ( 14 ), an inner pumping means ( 15 ) of the pump ( 2 ) is arranged inside the rotor ( 8 ), said inner pumping means ( 15 ) having a second pumping profile ( 17 ) on an outer circumferential surface ( 16 ), said second pumping profile ( 17 ) interacting with the first pumping profile ( 13 ) to pump a fluid ( 18 ).

1 . A pump arrangement comprising a pump having a pressure side and an intake side and a drive unit for the pump which are arranged in a common housing, wherein the drive unit is an axial flow electric drive which comprises a stator which is connected to the housing in a rotationally secure manner and a rotor which is arranged so as to be able to be rotated with respect to the housing, wherein the rotor is arranged with a first end face opposite the stator in an axial direction and forms an outer conveying means of the pump and has on an inner circumferential face a first conveying profile, wherein in a radial direction inside the rotor there is arranged an inner conveying means of the pump which has on an outer circumferential face a second conveying profile which cooperates with the first conveying profile in order to convey a fluid; wherein the inner conveying means is supported on a centering element which is connected to the housing in a rotationally secure manner; wherein at least the rotor and the outer conveying means are configured to be supported exclusively via the fluid conveyed by the pump; wherein at least between the first end face and the stator a first fluid guiding structure is arranged and connected to the pressure side so that during operation of the electric drive a gap between the first end face and the stator is producible by the fluid. 
     
     
         2 . The pump arrangement as claimed in  claim 1 , wherein the rotor extends between the first end face facing the stator and a second end face which is arranged opposite in the axial direction over a width, wherein the first conveying profile and the second conveying profile each extend over the width. 
     
     
         3 . The pump arrangement as claimed in  claim 1 , wherein the second conveying profile cooperates with the first conveying profile in order to drive the inner conveying means, wherein the inner conveying means is rotatably supported on the centering element; wherein the inner conveying means is also supported exclusively by the fluid conveyed by the pump. 
     
     
         4 . The pump arrangement as claimed in  claim 1 , wherein the housing has at a second end face, which is arranged opposite the first end face, of the rotor a pressure line which is connected to the pressure side, wherein the first fluid guiding structure is connected to the pressure line via the centering element. 
     
     
         5 . The pump arrangement as claimed in  claim 4 , wherein the inner conveying means is rotatably supported on a first outer circumferential face of the centering element, wherein a second fluid guiding structure for connecting the pressure line to the first fluid guiding structure is formed at least partially on the first outer circumferential face. 
     
     
         6 . The pump arrangement as claimed in  claim 1 , wherein the housing has at a second end face, which is arranged opposite the first end face, of the rotor an intake line which is connected to the intake side, wherein a leakage of the fluid from the first fluid guiding structure is carried out via a second outer circumferential face of the rotor in the direction toward the intake line. 
     
     
         7 . The pump arrangement as claimed in  claim 1 , wherein the rotor and the outer conveying means are configured in one piece. 
     
     
         8 . The pump arrangement as claimed in  claim 1 , wherein at least components, which rotate during operation of the pump arrangement, of the pump arrangement are arranged in a contact-free manner with respect to fixed components of the pump arrangement. 
     
     
         9 . The pump arrangement as claimed in  claim 1 , wherein at least the rotor is produced using powder metallurgy. 
     
     
         10 . The pump arrangement as claimed in  claim 1 , wherein the pump
 is a gerotor pump or an internal gear pump and the first conveying profile is a first tooth arrangement and the second conveying profile is a second tooth arrangement, wherein the tooth arrangements have mutually different numbers of teeth; or   is a vane cell pump or a roller cell pump;   and wherein a first rotation axis of the rotor and a second rotation axis of the inner conveying means are arranged parallel with each other and spaced apart from each other in the radial direction.