Brake apparatus for a bicycle

Abstract

A brake apparatus for use on a hub shaft ( 11 ) supporting a hub ( 2 ) of a bicycle has a brake ring ( 13 ), and a coupling device for coupling the brake ring and the hub to rotatable together. The coupling device includes outer splines ( 13 a) formed on the brake ring ( 13 ) and inner splines ( 2 d) formed in the hub ( 2 ) to allow relative axial movement between the brake ring ( 13 ) and hub ( 2 ) while preventing relative rotation therebetween. The brake apparatus includes brake shoes ( 6 ) disposed inside the brake ring ( 13 ) to be movable into contact with the brake ring ( 13 ). A restrictor is provided far restricting axial movement of the brake shoes ( 6 ) relative to the brake ring ( 13 ). The restrictor includes stoppers ( 27 a) projecting radially outwardly from peripheral positions of an annular shoe presser spring ( 27 ) fitted circumferentially of the brake shoes ( 6 ), and grooves ( 13 b) formed in an inner peripheral wall of the brake ring ( 13 ). The brake apparatus further includes a brake controller ( 7 ) for varying a radial distance of the brake shoes ( 6 ) from an axis of the hub shaft ( 11 ).

What is claimed is:  
     
       1. A brake apparatus for a bicycle, comprising: 
       a hub shaft, and means for fixedly mounting said hub shaft on a frame of said bicycle;  
       a hub rotatably mounted on said hub shaft;  
       brake shoe means disposed on said hub shaft, said brake shoe means being non-rotatable relative to said hub shaft;  
       a brake ring having a contact surface for contacting said brake shoe means, said brake ring being located radially outwardly of said brake shoe means with respect to said hub shaft, such that said brake shoe means is located between said brake ring and said hub shaft;  
       coupling means located radially between said brake ring and said hub for coupling said brake ring and said hub to be rotatable together, and preventing said brake ring from rotating relative to said hub;  
       restrictor means for restricting movement of said brake shoe means relative to said brake ring axially of said hub; and  
       brake control means for varying a radial distance of said brake shoe means from an axis of said hub shaft.  
     
     
       2. A brake apparatus as defined in claim  1 , further comprising unitary means for allowing installation of said brake ring, said brake shoe means and said brake control means as a unit. 
     
     
       3. A brake apparatus as defined in claim  2 , wherein said brake control means includes rollers for pushing said brake shoe means radially outwardly, a roller case for retaining said rollers, and a rotary cam for actuating said rollers. 
     
     
       4. A brake apparatus as defined in claim  3 , wherein said roller case has a first stopper for preventing said rotary cam from being separated from said roller case, and a second stopper for preventing said brake shoe means from being separated from said roller case. 
     
     
       5. A brake apparatus as defined in claims  4 , wherein said unitary means includes said restrictor means, said first stopper and said second stopper. 
     
     
       6. A brake apparatus as defined in claim  4 , wherein said first stopper and said second stopper are flanges extending radially from said roller case. 
     
     
       7. A brake apparatus as defined in claim  1 , wherein said coupling means includes first grooves  splines extending substantially in a direction of said hub shaft and provided on an inside face of said hub, and a plurality of second grooves  splines that engage said first grooves  splines. 
     
     
       8. A brake apparatus as defined in claim  1 , wherein said restrictor means is located between said brake ring and said brake shoe means. 
     
     
       9. A brake apparatus as defined in claim  8 , wherein said restrictor means includes a spring for biasing said brake shoe means radially inwardly toward said hub shaft and a groove defined in said brake ring, said spring being located within said groove. 
     
     
       10. A brake apparatus for coupling to and use with a bicycle hub that rotates around a hub shaft, said brake apparatus comprising: 
       
         a rotatable brake ring having a contact surface and a coupling element, said coupling element having a coupling structure which allows said brake ring to couple to said bicycle hub such that said coupling element is located radially between said brake ring and said hub and such that a relative rotation of said brake ring with respect to said bicycle hub is prohibited whenever said coupling element engages said bicycle hub while allowing said brake ring to be moved axially with respect to said bicycle hub during assembly to and disassembly from said bicycle hub;  
       
       
         brake shoe means located radially inside said brake ring; and  
       
       
         a brake control mechanism for moving said at least one brake shoe into braking contact with said contact surface of said brake ring.  
       
     
     
       11. A brake apparatus as in claim  10  wherein said coupling element, brake ring, at least one brake shoe, and brake control mechanism form part of a unitary assembly which is connectable as a unit to said hub shaft and said hub of said bicycle.  
     
     
       12. A brake apparatus as in claim  11  further comprising a support bushing for coupling said unitary assembly to said hub shaft of said bicycle.  
     
     
       13. A brake apparatus as defined in claim  12 , wherein said brake control mechanism includes rollers for pushing said brake shoe means radially outwardly and into contact with said brake ring, a roller case for retaining said rollers, and a rotary cam for actuating said rollers.  
     
     
       14. A brake apparatus as defined in claim  13 , wherein said roller case has a first stopper for preventing said rotary cam from being separated from said roller case, and a second stopper for preventing said brake shoe from being separated from said roller case.  
     
     
       15. A brake apparatus as defined in claim  14 , wherein said unitary assembly includes said first stopper and said second stopper.  
     
     
       16. A brake apparatus as defined in claim  14 , wherein said first stopper and said second stopper are flanges extending radially from said roller case.  
     
     
       17. A brake apparatus as defined in claim  10  further comprising a restrictor for axially restricting movement of said brake shoe means relative to said brake ring.  
     
     
       18. A brake apparatus as defined in claim  21  wherein said restrictor is located between said brake ring and said brake shoe means.  
     
     
       19. A brake apparatus as defined in claim  18 , wherein said restrictor includes a spring for biasing said brake shoe means radially inwardly and a groove defined in said brake ring, said spring being located within said groove.  
     
     
       20. A brake apparatus as defined in claim  10 , wherein said coupling element includes a spline.  
     
     
       21. A brake apparatus as defined in claim  10 , wherein said coupling element includes splines extending substantially in an axial direction of said brake ring which are adapted to engage with splines provided at said hub.  
     
     
       22. A brake apparatus for coupling to and use with a bicycle hub that rotates around a hub shaft, said brake apparatus comprising: 
       
         a rotatable brake ring having a coupling element and a contact surface normal to a radial direction, said coupling element having a coupling structure which allows said coupling element to couple to the bicycle hub such that said coupling element is located radially between said brake ring and said hub and such that a relative rotation of said brake ring with respect to said bicycle hub is prohibited while allowing said brake ring to be moved axially of said hub shaft during assembly to and disassembly from said bicycle hub;  
       
       
         brake shoe means located radially inside said brake ring, said brake shoe having a brake shoe surface normal to said radial direction;  
       
       
         a brake control mechanism for moving said brake shoe means into braking contact with said contact surface of said brake ring; and  
       
       
         a lock nut adapted to engage said hub shaft to prevent said brake ring from moving axially from said bicycle hub such that disengaging said nut from said hub shaft allows said brake ring, said brake shoe means and said brake control mechanism to move axially of said hub shaft.  
       
     
     
       23. A brake apparatus as defined in claim  22 , wherein said coupling element includes a spline.  
     
     
       24. A brake apparatus as defined in claim  22  further comprising a restrictor for axially restricting movement of said brake shoe means relative to said brake ring.