Composite fiber bicycle wheels

Abstract

Carbon fiber bicycle wheels are formed from parts cut from carbon fiber cloth and then joined together to form a rim, sidewalls, spokes, flanges and a center tunnel on which the flanges are mounted. The parts are then assembled, bonded together, and cured to form a wheel. During assembly, the spokes and the wheel are placed in tension by moving the flanges outwardly on the center tunnel after assembly and then bonding them in place to stiffen and strengthen the wheel. The spokes of the drive side of the rear wheel are specially shaped to accommodate torque transfer forces generated by pedaling.

1 . A carbon fiber bicycle wheel comprising:
 a rim having a center channel and first and second sides;   first and second sidewalls bonded to said first and second sides of said rim;   a plurality of flat spokes bonded to each of said sidewalls and extending inwardly toward first and second flanges, said flanges being laterally spaced from each other;   said first and second flanges having at least one portion extending radially outward, said spokes bonded to said at least one portion.   
     
     
         2 . The bicycle wheel of  claim 1 , wherein said first and second sidewalls are formed from arcuate segments of woven carbon fiber cloth;
 said arcuate segments partially overlapping each other to form a circular sidewall.   
     
     
         3 . The bicycle wheel of  claim 2 , wherein said sidewalls are formed layers of arcuate segments of woven carbon fiber cloth, said layers being circumferentially offset with respect to each other. 
     
     
         4 . The bicycle wheel of  claim 2 , wherein each of said arcuate segments of woven carbon fiber cloth are cut so that a maximum number of carbon fibers run from end to end of said segments. 
     
     
         5 . The bicycle wheel of  claim 1 , wherein at least one of said flanges is laterally moveably mounted with respect to the other such that laterally outward movement of said flanges tensions said spokes. 
     
     
         6 . The bicycle wheel of  claim 1 , wherein said flat spokes are cut from carbon fiber material such that the maximum number of carbon fibers run longitudinally along said spoke. 
     
     
         7 . The bicycle wheel of  claim 2 , wherein said spokes are bonded to said sidewalls at points where at least two of said arcuate segments of said sidewall overlap each other. 
     
     
         8 . The bicycle wheel of  claim 2 , wherein said sidewall is formed of at least one layer of overlapping arcuate segments and spokes are bonded thereto at said areas of overlap. 
     
     
         9 . The bicycle wheel of  claim 1 , wherein said spokes extend longitudinally and are widened at least one end to increase the size of the bonding surface between said spoke end and said sidewall or said flange. 
     
     
         10 . The bicycle wheel of  claim 1 , wherein said first and second sidewalls include a circumferential profile change, said flat spokes extending inwardly toward said flanges through slots in said sidewalls, said slots being located at said circumferential profile change. 
     
     
         11 . A carbon fiber bicycle wheel for the rear of a bicycle, comprising:
 a circular rim, first and second sidewalls bonded to said rim, a first set of spokes bonded to at least one of said sidewalls and extending inwardly for attachment to a first flange, a second set of spokes bonded to at least one of said sidewalls and extending inwardly for attachment to a second flange, said first flange and spokes differing in shape from said second flange and spokes.   
     
     
         12 . The rear bicycle wheel of  claim 11 , wherein said second set of spokes are bifurcated along their length adjacent the flange end of said spokes. 
     
     
         13 . The rear bicycle wheel of  claim 11 , wherein said first sidewall and set of spokes and flange are positioned on the left side of said rear bicycle wheel, and said second sidewall and set of spokes and flange are positioned on the right side of said wheel. 
     
     
         14 . The rear bicycle wheel of  claim 12 , wherein the bifurcated ends of said second set of spokes overlie each other and are bonded together. 
     
     
         15 . The rear bicycle wheel of  claim 14 , wherein said overlying spoke ends define a center opening shaped to mechanically mate with a like shaped portion of said associated flange. 
     
     
         16 . A method of making a bicycle wheel comprising the steps of:
 selecting a piece of woven carbon fiber cloth;   cutting pattern shapes from said cloth;   laying up said pattern shapes to form bicycle wheel parts including a rim, a pair of sidewalls, a pair of flanges, and a plurality of spokes;   curing said laid up bicycle wheel parts;   bonding said cured parts together with adhesive to form a wheel and curing said bonded parts;   joining said flanges in laterally spaced relation; and   moving said flanges laterally apart to create tension in said spokes and bonding said flanges to maintain said tension in said spokes.   
     
     
         17 . The method of  claim 16 , wherein the step of joining said flanges in laterally spaced relation includes the step of mounting said flanges on a tubular tunnel. 
     
     
         18 . The method of  claim 17 , wherein the step of moving said flanges laterally apart and bonding them in place, includes the steps of forming one of said flanges to include a laterally extending tube and mounting the second of said flanges on said tube;
 moving said second flange laterally outward on said tubular tunnel, and bonding said second flange in place.   
     
     
         19 . The method of  claim 16 , wherein the step of cutting pattern shapes from said woven carbon fiber cloth to form said pair of sidewalls includes the step of cutting said pattern shapes in an arc so that a maximum number of carbon fibers extend from end to end of said arcuate pattern shape. 
     
     
         20 . The method of  claim 16 , wherein the step of laying up said pattern shapes includes the step of laying up said shapes such that a maximum number of the carbon fibers run end to end in said parts. 
     
     
         21 . The method of  claim 16 , wherein the steps of cutting and laying up said pattern shapes to form a sidewall includes the steps of cutting arcuate segments and laying said segments end to end such that their ends overlap. 
     
     
         22 . The method of  claim 16 , wherein the step of laying up said pattern shapes to form a rim includes the step of wrapping said rim pattern shapes around a filler piece.