Pump for Liquids Under Positive Pressure

Abstract

A pump for liquids at positive pressure, includes a pump chamber ( 18 ) accommodating an impeller ( 24 ), wherein the impeller ( 24 ) is axially biased against a non-rotating support element ( 48 ) which determines the axial position of the impeller ( 24 ). The shaft ( 42 ) may be coupled to a drive shaft ( 64 ) through a magnet coupling ( 56, 62 ).

1 . Pump for liquids at positive pressure, comprising:
 an impeller,   at least one pump chamber accommodating the impeller,   a non-rotating support element, and   the impeller is axially biased against the non-rotating support element which defines an axial position of the impeller.   
   
   
       2 . Pump according to  claim 1 ,
 further comprising a shaft which is axially biased against the support element, and   wherein the impeller is fixedly mounted on the shaft.   
   
   
       3 . Pump according to  claim 1 , further comprising at least one radial slide bearing which supports the shaft. 
   
   
       4 . Pump according to  claim 3 , further comprising a flush passage passing through a wall of the pump chamber for flushing said at least one radial slide bearing and which connects a pressure-side portion of the pump chamber to a portion situated beyond the slide bearing. 
   
   
       5 . Pump according to  claim 3 , further comprising a flush passage for flushing said at least one slide bearing and which is formed by a passage which passes axially through the shaft.  
   
   
       6 . Pump according to  claim 1 , wherein a radial play between the impeller and a wall of the pump chamber amounts to not more than 1/10 mm. 
   
   
       7 . Pump according to  claim 1 , wherein, on both sides of the impeller, an axial play between the impeller and a respective wall of the pump chamber amounts to not more than 1/10 mm. 
   
   
       8 . Pump according to  claim 1 , further comprising:
 a magnet coupling for coupling the shaft to a drive shaft, the magnet coupling including a first coupling member connected to the shaft, and a second coupling member connected to the drive shaft, and   a wall, which seals a drive-side portion of the pump against a portion accommodating the shaft and the pump chamber, passes through a gap between the first and second coupling members.   
   
   
       9 . Pump according to  claim 8 , wherein the first coupling member and the second coupling member are arranged in such relative positions that the magnet coupling biases the shaft axially against the support element. 
   
   
       10 . Pump according to  claim 1 , further comprising a compression spring which axially biases the shaft against the support element.