Pump with turbulence inducing tab

Abstract

A centrifugal pump has a pump case and a rotatable impeller disposed within the pump case. A central aperture is defined within the rearward wall of the pump case to facilitate the connection of an impeller drive shaft to the impeller. A drive shaft seal is disposed within the central aperture to seal the impeller drive shaft to the pump case. A tab is disposed within the pump case such that it protrudes away from the rearward wall of the pump case. The tab is sized, dimensioned and located so as to create sufficient turbulence proximate to the drive shaft seal to suppress the buildup of heat and chemical precipitates around the drive shaft seal.

1 . A centrifugal pump comprising: 
 (a) a pump case having a forward wall, a rearward wall, and one or more side walls, the forward wall defining a central inlet opening, the one or more side walls defining a tangential outlet opening and the rearward wall defining a central drive shaft opening;    (b) a rotatable impeller disposed within the pump case;    (c) a drive shaft disposed through the drive shaft central opening and operatively attached to the impeller;    (d) a drive shaft seal disposed around the drive shaft opening to seal the drive shaft to the pump case; and    (e) a tab disposed within the pump case, the tab being attached to, and protruding away from, the rearward wall of the pump case and being sized, dimensioned and located so as to create sufficient turbulence proximate to the drive shaft seal, while the pump is in use to pump a liquid, to suppress the buildup of chemical precipitates around the drive shaft seal.    
   
   
       2 . The centrifugal pump of  claim 1  wherein the tab is sized, dimensioned and located so as to create sufficient turbulence proximate to the drive shaft seal, while the pump is in use to pump an aqueous solution, to suppress the buildup of chemical precipitates around the drive shaft seal.  
   
   
       3 . The centrifugal pump of  claim 1  wherein the tab has a height of between about 0.1 inch and about 1 inch.  
   
   
       4 . The centrifugal pump of  claim 1  wherein the tab has a width of between about 0.5 inch and about 1 inch.  
   
   
       5 . The centrifugal pump of  claim 1  wherein the tab has at least one sharp free corner.  
   
   
       6 . The centrifugal pump of  claim 1  wherein the outlet opening and the impeller are disposed in the same plane.  
   
   
       7 . The centrifugal pump of  claim 1  wherein the center of the outlet opening and the impeller are disposed in substantially the same plane.  
   
   
       8 . The centrifugal pump of  claim 1  further comprising a flow guide disposed within the pump case, the flow guide comprising a first baffle surface and an attached second baffle surface, the first baffle surface being arcuate and being longer than the second baffle surface, the junction of the first baffle surface and the second baffle surface defining an angle greater than 90°, the first baffle surface being spaced apart from the impeller by a distance which is less than the distance between the impeller and the at least one side wall of the pump case, the second baffle surface being disposed proximate to the outlet opening.  
   
   
       9 . A centrifugal pump comprising: 
 (a) a pump case having a forward wall, a rearward wall, and one or more side walls, the forward wall defining a central inlet opening, the one or more side walls defining a tangential outlet opening and the rearward wall defining a central drive shaft opening;    (b) a rotatable impeller disposed within the pump case;    (c) a drive shaft disposed through the drive shaft central opening and operatively attached to the impeller;    (d) a drive shaft seal disposed around the drive shaft opening to seal the drive shaft to the pump case; and    (e) a tab disposed within the pump case, the tab being attached to, and protruding away from, the rearward wall of the pump case, the tab having a height between about 0.2 inch and about 1 inch and a width between about 0.1 inch and about 1 inch, the tab being further sized, dimensioned and located so as to create sufficient turbulence proximate to the drive shaft seal, while the pump is in use to pump an aqueous solution, to suppress the buildup of chemical precipitates around the drive shaft seal.    
   
   
       10 . The centrifugal pump of  claim 9  wherein the tab has at least one sharp free corner.  
   
   
       11 . The centrifugal pump of  claim 9  wherein the outlet opening and the impeller are disposed in the same plane.  
   
   
       12 . The centrifugal pump of  claim 9  wherein the center of the outlet opening and the impeller are disposed in substantially the same plane.  
   
   
       13 . The centrifugal pump of  claim 9  further comprising a flow guide disposed within the pump case, the flow guide comprising a first baffle surface and an attached second baffle surface, the first baffle surface being arcuate and being longer than the second baffle surface, the junction of the first baffle surface and the second baffle surface defining an angle greater than 90°, the first baffle surface being spaced apart from the impeller by a distance which is less than the distance between the impeller and the at least one side wall of the pump case, the second baffle surface being disposed proximate to the outlet opening.  
   
   
       14 . A centrifugal pump comprising: 
 (a) a pump case having a forward wall, a rearward wall, and one or more side walls, the forward wall defining a central inlet opening, the one or more side walls defining a tangential outlet opening and the rearward wall defining a central drive shaft opening;    (b) a rotatable impeller disposed within the pump case;    (c) a drive shaft disposed through the drive shaft central opening and operatively attached to the impeller; and    (d) a drive shaft seal disposed around the drive shaft opening to seal the drive shaft to the pump case;    wherein the outlet opening and the impeller are disposed in the same plane.    
   
   
       15 . The centrifugal pump of  claim 14  wherein the center of the outlet opening and the impeller are disposed in substantially the same plane.  
   
   
       16 . The centrifugal pump of  claim 14  further comprising a flow guide disposed within the pump case, the flow guide comprising a first baffle surface and an attached second baffle surface, the first baffle surface being arcuate and being longer than the second baffle surface, the junction of the first baffle surface and the second baffle surface defining an angle greater than 90°, the first baffle surface being spaced apart from the impeller by a distance which is less than the distance between the impeller and the at least one side wall of the pump case, the second baffle surface being disposed proximate to the outlet opening.