Polymeric compressor wheel assembly

Abstract

A compressor wheel assembly ( 200 ) includes a compressor wheel ( 140 ) and a coupling member ( 230 ). The compressor wheel ( 140 ) is formed of a polymeric material. The compressor wheel ( 140 ) includes a hub ( 202 ), blades ( 204 ) extending from a forward surface ( 210 ) of the hub ( 202 ), and a shaft coupling portion ( 206 ) extending axially rearward from a rearward surface of the hub ( 202 ). The shaft coupling portion ( 206 ) includes a bore ( 208 ) extending therethrough and having a polygonal cross-sectional configuration. The coupling member ( 230 ) includes a head ( 232 ) and a body ( 234 ) extending axially from the head ( 232 ). The head ( 232 ) is received against a forward end ( 216 ) of the compressor wheel ( 140 ) and the body ( 234 ) extends through the bore ( 208 ). The body ( 234 ) has another polygonal cross-sectional configuration for transferring torque from the coupling member ( 23 ) to the compressor wheel ( 140 ).

What is claimed is: 
     
         1 . A compressor wheel assembly ( 200 ), comprising:
 a compressor wheel ( 140 ) formed of a polymeric material, the compressor wheel ( 140 ) comprising a hub ( 202 ), blades ( 204 ) extending from a forward surface ( 210 ) of the hub ( 202 ), and a shaft coupling portion ( 206 ) extending axially rearward from a rearward surface of the hub ( 202 ), wherein the shaft coupling portion ( 206 ) includes a bore ( 208 ) extending therethrough and having a polygonal cross-sectional configuration; and   a coupling member ( 230 ) having a head ( 232 ) and a body ( 234 ) extending axially from the head ( 232 ), wherein the head ( 232 ) is received against a forward end ( 216 ) of the compressor wheel ( 140 ) and the body ( 234 ) extends through the bore ( 208 ), and the body ( 234 ) has another polygonal cross-sectional configuration for transferring torque from the coupling member ( 230 ) to the compressor wheel ( 140 ).   
     
     
         2 . The compressor wheel assembly ( 200 ) according to  claim 1 , wherein the polygonal cross-sectional configuration of the bore ( 208 ) and the other polygonal cross-sectional configuration of the body ( 234 ) are square. 
     
     
         3 . The compressor wheel assembly ( 200 ) according to  claim 1 , wherein the bore ( 208 ) includes interior surfaces ( 220 ) that are straight and interior curved surfaces extending therebetween to form the polygonal cross-sectional configuration, and the body ( 234 ) includes exterior surfaces ( 240 ) that are straight and exterior curved surfaces extending therebetween to form the other polygonal cross-sectional configuration. 
     
     
         4 . The compressor wheel assembly ( 200 ) according to  claim 1 , wherein the polygonal cross-sectional configuration extends an axial length of the bore ( 208 ), and the other polygonal cross-sectional configuration extends another axial length of the body ( 234 ), wherein the other axial length of the bore ( 208 ) is greater than or equal to the axial length of the body ( 234 ). 
     
     
         5 . The compressor wheel assembly ( 200 ) according to  claim 1 , wherein the coupling member ( 230 ) is formed of a material that is stiffer than the polymeric material. 
     
     
         6 . The compressor wheel assembly ( 200 ) according to  claim 1 , further comprising,
 a shaft ( 160 );   wherein the body ( 234 ) of the coupling member ( 230 ) includes a hollow interior; and   wherein the shaft ( 160 ) includes a forward portion ( 262 ) that is threadably received in the hollow interior to couple the shaft ( 160 ) to the coupling member ( 230 ) and transfer torque thereto as the shaft ( 160 ) is rotated by a drive source.   
     
     
         7 . The compressor wheel assembly ( 200 ) according to  claim 6 , wherein the shaft ( 160 ) includes a rearward portion ( 260 ) having a diameter that is larger than a diameter of the forward portion ( 262 ) and from which the forward portion ( 262 ) extends forward axially, and a rearward end ( 238 ) of the coupling member ( 230 ) seats against a shoulder ( 266 ) extending radially between the rearward portion ( 260 ) and the forward portion ( 262 ). 
     
     
         8 . The compressor wheel assembly ( 200 ) according to  claim 6 , wherein the forward portion ( 262 ) is received by the hollow interior to couple the shaft ( 160 ) to the coupling member ( 230 ), and a void ( 270 ) is formed axially between an interior end surface ( 272 ) of the body ( 234 ) and a forward end ( 264 ) of the shaft ( 160 ). 
     
     
         9 . The compressor wheel assembly ( 200 ) according to  claim 8 , wherein the hollow interior of the body ( 234 ) extends axially forward of the forward end ( 216 ) of the compressor wheel ( 140 ), and the forward end ( 264 ) of the shaft ( 160 ) terminates rearward of the forward end ( 216 ) of the compressor wheel ( 140 ). 
     
     
         10 . The compressor wheel assembly ( 200 ) according to  claim 6 , further comprises a collar ( 280 ) disposed around and engages the shaft coupling portion ( 206 ), and the collar ( 280 ) is formed of a material that is stiffer than the polymeric material. 
     
     
         11 . The compressor wheel assembly according to  claim 10 , wherein the collar ( 280 ) surrounds the coupling member ( 230 ). 
     
     
         12 . A compressor wheel assembly ( 200 ) comprising:
 a compressor wheel ( 140 ) formed of a polymeric material, the compressor wheel ( 140 ) comprising a hub ( 202 ), blades ( 204 ) extending from a forward surface ( 210 ) of the hub ( 202 ), and a shaft coupling portion ( 206 ) extending axially rearward from a rearward surface of the hub ( 202 ); wherein the shaft coupling portion ( 206 ) includes a bore ( 208 ) extending therethrough and having a polygonal cross-sectional configuration:   a coupling member ( 230 ) formed of a material stiffer than the polymeric material and having a head ( 232 ) and a body ( 234 ) extending axially from the head ( 232 ) and having a hollow interior, wherein the head ( 232 ) is received against a forward end ( 216 ) of the compressor wheel ( 140 ) and the body ( 234 ) extends through the bore ( 208 ), and the body ( 234 ) has another polygonal cross-sectional configuration for transferring torque from the coupling member ( 230 ) to the compressor wheel ( 140 ); and   a shaft ( 160 ) having a forward portion ( 262 ) that is threadably received in the hollow interior to couple the shaft ( 160 ) to the coupling member ( 230 ) and transfer torque thereto as the shaft is ( 160 ) rotatably driven.   
     
     
         13 . The compressor wheel assembly ( 200 ) according to  claim 12 , wherein the polygonal cross-sectional configuration of the bore ( 208 ) and the body ( 234 ) are square or comprise straight and curved surfaces. 
     
     
         14 . The compressor wheel assembly ( 200 ) according to  claim 12 , further comprising a collar ( 280 ) disposed around and engaging the shaft coupling portion ( 206 ) wherein the collar ( 280 ) is formed of a material that is stiffer than the polymeric material. 
     
     
         15 . The compressor wheel assembly ( 200 ) according to  claim 12 , wherein the polygonal cross-sectional configuration extends an axial length of the bore ( 208 ), and the other polygonal cross-sectional configuration extends another axial length of the body ( 234 ), wherein the other axial length of the bore ( 208 ) is greater than or equal to the axial length of the body ( 234 ).