Centrifugal pump

Abstract

A centrifugal pump is proposed, in particular for household appliances, such as washing machines or dishwashers, with a pump housing, whose exterior shape is essentially radially symmetrical, and which has an axial inlet and a peripheral outlet, along with a rotatably mounted impeller, wherein a flow channel enveloping the impeller and heating element is provided. In such a centrifugal pump, the object is to increase the efficiency by having the flow cross-section of the flow channel ( 15 ) increase along the periphery toward the outlet.

1 . A centrifugal pump, for household appliances, such as washing machines or dishwashers, having a pump housing, with a substantially radially symmetrical exterior having an axial inlet and a peripheral outlet, along with a rotatably mounted impeller, wherein the improvement comprises a flow channel enveloping the impeller said flow channel ( 15 ) having an increase in cross section along the periphery toward the outlet.  
   
   
       2 . The pump according to  claim 1 , wherein the pump housing has an essentially cylindrical exterior shape.  
   
   
       3 . The pump according to  claim 1  wherein the axial dimension (h, H) of the flow channel ( 15 ) increases along the periphery toward the outlet ( 12 ).  
   
   
       4 . The pump according to  claim 1  or  3  wherein the flow channel ( 15 ) has a bottom ( 17 ) that is upwardly sloped toward the outside.  
   
   
       5 . The pump according to  claim 1  wherein the interior of the flow channel ( 15 ) is provided with a continuous inlet gap ( 14 ).  
   
   
       6 . The pump according to  claim 1  wherein the continuous inlet gap ( 14 ) has an essentially constant height.  
   
   
       7 . The pump according to  claim 1  wherein the impeller ( 4 ) has an annular gap ( 13 ) lying at roughly the height of the inlet gap ( 14 ) of the flow channel.  
   
   
       8 . The pump according to  claim 7  wherein the height of the annular gap ( 13 ) of the impeller ( 4 ) is smaller than or equal to the height of the continuous inlet gap ( 14 ) of the flow channel ( 15 ).  
   
   
       9 . The pump according to  claim 1  wherein the volume of the impeller ( 4 ) increases in an axial direction.  
   
   
       10 . The pump according to  claim 1  further comprising a heating element and wherein the volume increase of the impeller ( 4 ) is arranged on the side of the impeller ( 4 ) facing away from the heating element ( 22 ).  
   
   
       11 . The pump according to  claim 1  wherein the inlet comprises an axial inlet support ( 11 ) that extends into an inlet opening ( 10 ) of the impeller ( 4 ).  
   
   
       12 . The pump according to  claim 1  further comprising a heating element ( 22 ).  
   
   
       13 . The pump according to  claim 1  further comprising a heating element ( 22 ) wherein said heating element is separated from the interior space of the pump by a heat-conducting wall of the pump housing.  
   
   
       14 . The pump according to  claim 1  further comprising a heating element wherein the heating element ( 22 ) is incorporated into a groove of the pump housing.  
   
   
       15 . The pump according to  claim 1  further comprising a heating element wherein the axial dimension (h, H) of the flow channel ( 15 ) increases on the side opposite the heating element ( 22 ) along the periphery toward the outlet ( 12 ).  
   
   
       16 . The pump according to  claim 1  further comprising a heating element wherein the heating element ( 22 ) is arranged on the side of the impeller ( 4 ) facing the axial inlet ( 11 ) of the pump housing ( 2 ).  
   
   
       17 . The pump according to  claim 12  wherein the heating element ( 22 ) is of a substantially annular configuration.  
   
   
       18 . The pump according to  claim 1  further comprising a heating element wherein the side of the impeller ( 4 ) facing the heating element ( 22 ) is matched to the profile of the heating element ( 22 ) or its receptacle ( 16 ) in the pump housing ( 2 ).  
   
   
       19 . The pump according to  claim 1  wherein said pump is disposed in a washing machine or a dishwasher.