Impeller Assembly

Abstract

An impeller assembly including a rim plate defining a plurality of blades and the backplate defining a blade interlock structure for aligning and coupling the plates together. The rim plate defines a plurality of fluid-engaging blades. The interlock structure includes a plurality of tine-shaped interlocks extending from the backplate. The interlock structure also includes a plurality of channel sections engaging the blades. Each blade of the impeller may engage the interlock structure in a saddle manner. The backplate is defined by areas of reduced thickness allowing outer portions of the backplate to flex (rotate) toward further contact with the rim plate.

1 . An impeller assembly comprising:
 a generally circular rim plate having a center hub for connection to a drive shaft;   a generally circular backplate;   a plurality of blades between the rim plate and the backplate, with said plurality of blades extending from the rim plate; and   a blade interlock structure, said blade interlock structure including blade interlocks engaging sides of said plurality of blades, said blade interlock structure providing a torque coupling between the rim plate and the backplate.   
     
     
         2 . The impeller assembly of  claim 1  with said blade interlock structure wherein the blade interlocks are radially-aligned relative to a backplate center. 
     
     
         3 . The impeller assembly of  claim 1  wherein the plurality of blades extend from the center hub of the rim plate. 
     
     
         4 . The impeller assembly of  claim 3  wherein the center hub includes an aperture for receiving the drive shaft to rotate the impeller assembly during operation. 
     
     
         5 . The impeller assembly of  claim 1  wherein the backplate includes an area of reduced thickness between a center of the backplate and an outer edge of the backplate, with said area of reduced thickness causing the backplate to flex toward the rim plate. 
     
     
         6 . The impeller assembly of  claim 1  wherein the blade interlock structure includes a central blade interlock structure separated from a radially-outer interlock structure. 
     
     
         7 . The impeller assembly of  claim 6  wherein the radially-outer interlock structure defines a plurality of channels, with each channel being sized to engage side surfaces of one of the plurality of blades. 
     
     
         8 . The impeller assembly of  claim 6  wherein the central blade interlock structure includes a plurality of tines. 
     
     
         9 . The impeller assembly of  claim 8  wherein the plurality of tines engage the blades of the impeller. 
     
     
         10 . An impeller assembly comprising:
 a generally circular rim plate having a center hub for connection to a drive shaft;   a generally circular backplate;   a plurality of blades between the rim plate and the backplate, with said plurality of blades extending from the rim plate; and   a blade interlock structure on said backplate for engaging the plurality of blades, said blade interlock structure providing a coupling between the plurality of blades and the backplate.   
     
     
         11 . The impeller assembly of  claim 10  further comprising an interlock structure of a plurality of radially-aligned blade interlocks. 
     
     
         12 . The impeller assembly of  claim 10  wherein the plurality of blades extend from the center hub of the rim plate. 
     
     
         13 . The impeller assembly of  claim 12  wherein the center hub includes an aperture for receiving the drive shaft to rotate the impeller assembly during operation. 
     
     
         14 . The impeller assembly of  claim 10  wherein the backplate includes an area of reduced thickness between a center of the backplate and an outer edge of the backplate, with said area of reduced thickness causing the backplate to flex toward the rim plate. 
     
     
         15 . The impeller assembly of  claim 10  wherein the blade interlock structure includes a central blade interlock structure separated from a radially-outer interlock structure. 
     
     
         16 . The impeller assembly of  claim 15  wherein the radially-outer interlock structure defines a plurality of channels, with each channel being sized to engage side surfaces of one of the plurality of blades. 
     
     
         17 . The impeller assembly of  claim 15  wherein the central blade interlock structure includes a plurality of tines. 
     
     
         18 . The impeller assembly of  claim 17  wherein the plurality of tines engage the blades of the impeller. 
     
     
         19 . An impeller assembly comprising:
 a generally circular rim plate having a center hub for connection to a drive shaft;   a generally circular backplate having a base with an area of reduced thickness between a center axis of the backplate and an outer edge, said area of reduced thickness allowing an outer portion of the backplate to flex toward further contact with the rim plate during rotation of the impeller assembly;   a plurality of blades between the rim plate and the backplate, with said plurality of blades extending from the rim plate; and   a blade interlock structure, said blade interlock structure including interlocks engaging sides of said plurality of blades, said blade interlock structure providing a torque coupling between the rim plate and the backplate.   
     
     
         20 . The impeller assembly of  claim 19  wherein the blade interlock structure includes a plurality of tines extending toward the rim plate and a plurality of channel sections, with the area of reduced thickness being positioned between the plurality of tines and the plurality of channel sections.