Cable disc brake

Abstract

A bicycle cable disc brake is provided with a cam assembly that has improved efficiency during movement under high pressure. Basically, the cable disc brake has a cable housing, a pair of friction members and an actuated mechanism. The first friction member is movably coupled to the caliper housing between a release position and a braking position. The second caliper is also coupled to the caliper housing and arranged substantially parallel to the first friction member to form a rotor receiving slot therebetween. The actuated mechanism is movably coupled to the caliper housing to move the first friction member from the release position towards the second friction member to the braking position. The actuated mechanism has a pair of cam members movably arranged between an axially retracted position and an axially extended position with a guide member interconnecting the cam members during movement between the axial retracted position and the axially extended position. In the preferred embodiment, the guide member is a guide pin that extends from one of the cam members and is received in a bore of the other cam member.

1. A cable disc brake for a bicycle comprising:
 a caliper housing with a mounting bracket structured and dimensioned to be attached to a bicycle; 
 a first friction member movably coupled to said caliper housing between a release position and a braking position; 
 a second friction member coupled to said caliper housing and arranged substantially parallel to said first friction member to form a rotor receiving slot therebetween; and 
 an actuated mechanism movably coupled to said caliper housing to move said first friction member in an axial direction from said release position towards said second friction member to said braking position, said actuated mechanism including
 an input cam movably mounted within said caliper housing to move in a rotational direction about a longitudinal axis, but not in an axial direction, said input cam having a first camming surface with an axially extending guide member non-movably fixed thereto at said longitudinal axis, and 
 an output cam movably mounted within said caliper housing to move in the axial direction in response to rotation of said input cam, but not in the rotational direction, said output cam having a second camming surface with an axially extending bore, said guide member being at least partially disposed within said bore to ensure smooth relative movement between said input and output cams; 
 
 wherein said input cam and said output cam move axially relative to each other without such movement being caused by one of said input cam member or said output cam member screwing through the other one of said input cam member or said output cam member. 
 
     
     
       2. A cable disc brake according to  claim 1 , wherein
 said guide member is formed by a pin extending from said input cam into said bore of said output cam. 
 
     
     
       3. A cable disc brake according to  claim 2 , wherein
 said pin is integrally formed with said input cam. 
 
     
     
       4. A cable disc brake according to  claim 2 , wherein
 said first camming surface of said input cam has a set of first camming slots, said second camming surface of said output cam has a set of second camming slots with rolling members located between said first and second camming slots. 
 
     
     
       5. A cable disc brake according to  claim 4 , wherein
 said rolling members are balls and said first and second camming slots are circumferentially extending ramp-shaped slots. 
 
     
     
       6. A cable disc brake according to  claim 1 , wherein
 said actuated mechanism further includes an actuating arm operatively coupled to said input cam. 
 
     
     
       7. A cable disc brake according to  claim 6 , wherein said actuating arm is biased to a release position by a biasing member. 
     
     
       8. A cable disc brake according to  claim 7 , wherein
 said biasing member is a torsion spring with a first end coupled to said caliper housing a second end coupled to said actuating arm. 
 
     
     
       9. A cable disc brake according to  claim 8 , wherein
 said actuated mechanism includes a return spring arranged to bias said first and second cam members together. 
 
     
     
       10. A cable disc brake according to  claim 9 , wherein
 said actuating arm has a cable attachment member thereon. 
 
     
     
       11. A cable disc brake for a bicycle comprising:
 a caliper housing with a mounting bracket structured and dimensioned to be attached to a bicycle; 
 a first friction member movably coupled to said caliper housing between a release position and a braking position; 
 a second friction member coupled to said caliper housing and arranged substantially parallel to said first friction member to form a rotor receiving slot therebetween; and 
 an actuated mechanism movably coupled to said caliper housing to move said first friction member from said release position towards said second friction member to said braking position, said actuated mechanism having first and second cam members movably arranged between an axially retracted position and an axially extended position with a guide member interconnecting said first and second cam members during movement between said axially retracted position and said axially extended position, said guide member being non-movable in the axial direction relative to said caliper housing, 
 said first cam member being rotatably mounted within said caliper housing, but non-movably mounted in the axial direction, and said second cam member being movably mounted in the axial direction but non-rotatably mounted; 
 wherein said input cam and said output cam move axially relative to each other without such movement being caused by one of said input cam member or said output cam member screwing through the other one of said input cam member or said output cam member. 
 
     
     
       12. A cable disc brake according to  claim 11 , wherein
 said guide member is formed by a pin extending from one of said first and second cam members into a bore of the other of said first and second cam members. 
 
     
     
       13. A cable disc brake according to  claim 12 , wherein
 said pin is located along an axis of rotation of said first and second cam members. 
 
     
     
       14. A cable disc brake according to  claim 13 , wherein
 said actuated mechanism further includes an actuating arm coupled to said first cam member. 
 
     
     
       15. A cable disc brake according to  claim 14 , wherein
 said actuating arm is biased to a release position by a biasing member. 
 
     
     
       16. A cable disc brake according to  claim 15 , wherein
 said biasing member is a torsion spring with a first end coupled to said caliper housing a second end coupled to said actuating arm. 
 
     
     
       17. A cable disc brake according to  claim 16 , wherein
 said actuated mechanism includes a return spring arranged to bias said first and second cam members together. 
 
     
     
       18. A cable disc brake according to  claim 17 , wherein
 said actuating arm has a cable attachment member thereon. 
 
     
     
       19. A cable disc brake according to  claim 11 , wherein
 said first cam member has a set of first camming surfaces, said second cam member has a set of second camming surfaces with rolling members located between said first and second camming surfaces. 
 
     
     
       20. A cable disc brake according to  claim 19 , wherein
 said rolling members are balls and said first and second camming surfaces include ramp-shaped slots. 
 
     
     
       21. A cable disc brake according to  claim 1 , wherein
 said input cam includes a first cam member disposed within an internal bore of said caliper housing. 
 
     
     
       22. A cable disc brake according to  claim 21 , wherein
 said input cam further includes an operating shaft that extends axially from said first cam member, and said operating shaft is operatively coupled to an actuating arm. 
 
     
     
       23. A cable disc brake according to  claim 22 , wherein
 said operating shaft at least partially extends outwardly from said caliper housing, and said actuating arm is disposed on an opposite side of said caliper housing from said internal bore of said caliper housing. 
 
     
     
       24. A cable disc brake according to  claim 22 , wherein
 said input cam further includes a bushing mounted on said operating shaft of said input cam. 
 
     
     
       25. A cable disc brake according to  claim 24 , wherein
 said bushing includes a cylindrical portion at least partially surrounding said operating shaft and a flange portion extending from said cylindrical portion, and said flange portion is located axially between a portion of said input cam and said caliper housing within said internal bore of said caliper housing. 
 
     
     
       26. A cable disc brake according to  claim 21 , wherein
 said output cam includes a second cam member with a non-circular thrust shaft extending axially therefrom, and said thrust shaft is received in a non-circular hole of a rotation stopper. 
 
     
     
       27. A cable disc brake according to  claim 26 , wherein
 said rotation stopper includes a radially extending tab that is received in an axial slot of said caliper housing to prevent rotation of said rotation stopper. 
 
     
     
       28. A cable disc brake according to  claim 27 , wherein
 said rotation stopper is secured on said thrust shaft of said output cam by a retainer. 
 
     
     
       29. A cable disc brake according to  claim 28 , wherein
 said retainer is a c-shaped snap ring that is received in an annular groove of said internal bore of said caliper housing. 
 
     
     
       30. A cable disc brake according to  claim 26 , wherein
 said actuated mechanism includes a return spring disposed between said rotation stopper and a portion of said output cam. 
 
     
     
       31. A cable disc brake according to  claim 16 , wherein
 said torsion spring is adjustably coupled to said caliper housing and said actuating arm to adjust the biasing force of said torsion spring. 
 
     
     
       32. A cable disc brake according to  claim 22 , wherein
 said actuated mechanism includes a cover disposed between said actuating arm and said caliper housing to seal said internal bore of said caliper housing. 
 
     
     
       33. A cable disc brake according to  claim 32 , wherein
 said actuating arm is biased to a release position by a biasing member arranged between said cover and said caliper housing. 
 
     
     
       34. A cable disc brake according to  claim 17 , wherein
 said return spring is a separate member from said biasing member. 
 
     
     
       35. A cable disc brake according to  claim 34 , wherein
 said return spring is located axially on an opposite side of said input and output cams from said biasing member. 
 
     
     
       36. A cable disc brake according to  claim 1 , wherein
 said axially extending bore of said output cam is a blind bore. 
 
     
     
       37. A cable disc brake according to claim 1 wherein a force between said input cam and said output cam that causes said output cam to move axially from operation of said first camming surface and said second camming surface is disposed radially outwardly from said bore.  
     
     
       38. A cable disc brake according to claim 11 wherein a force between said input cam and said output cam that causes said output cam to move axially from operation of said first camming surface and said second camming surface is disposed radially outwardly from said bore.  
     
     
       39. A cable disc brake for a bicycle comprising:
 a caliper housing with a mounting bracket structured and dimensioned to be attached to a bicycle and with a cable support having an opening for guiding a cable therethrough;   a first friction member coupled to the caliper housing for movement between a release position and a braking position;   a second friction member coupled to the caliper housing and arranged substantially parallel to the first friction member to form a rotor receiving slot therebetween; and   an actuated mechanism movably coupled to the caliper housing to move the first friction member in an axial direction from the release position towards the second friction member to the braking position;   wherein the actuated mechanism comprises an elongated actuating arm coupled to the caliper housing for rotation around a rotational axis to cause the actuated mechanism to move the first friction member from the release position towards the braking position;   wherein the actuating arm has a curved guide surface with a first portion coincident with a cable clamp and a second portion that extends from the first portion towards the cable support so that the cable, when coupled to the cable clamp, approaches the guide surface from the opening in the cable support essentially tangent to the guide surface and is supported by the guide surface when the first friction member is in the release position;   wherein the second portion of the guide surface is formed by a circumferentially elongated projection that points in a rotational direction of the actuating arm towards the cable support where the cable passes through the cable support such that the cable is supported on and by the projection;   wherein the projection includes:
 a radially outer portion having a first surface that forms the second portion of the guide surface, wherein the first surface extends towards the cable support; and 
 a radially inner portion having a second surface that extends away from the cable support back towards a side surface of the actuating arm; 
 wherein a straight phantom line perpendicular to the first surface where the cable is supported on the first surface intersects the second surface.  
   
     
     
       40. A cable disc brake according to claim 39 wherein the projection is disposed in close proximity to a radially outermost portion of the actuating arm.  
     
     
       41. A cable disc brake according to claim 39 further comprising a cable adjusting bolt fitted within the opening in the cable support through which the cable passes.  
     
     
       42. A cable disc brake according to claim 39 wherein the caliper housing includes a mounting flange for mounting the caliper housing to the bicycle, and wherein the mounting flange includes a slot that allows adjustment of the caliper housing to and from the rotor such that the caliper housing is axially fixed relative to the rotor during operation of the actuating arm.  
     
     
       43. A cable disc brake according to claim 39 wherein the caliper housing includes a mounting flange for mounting the caliper housing to the bicycle, and wherein the mounting flange includes an opening for receiving a mounting bolt therethrough substantially perpendicular to the rotational axis.  
     
     
       44. A cable disc brake according to claim 39 wherein the caliper housing includes:
 a first mounting flange with a first opening for mounting the caliper housing to the bicycle;   a second mounting flange with a second opening for mounting the caliper housing to the bicycle;   wherein the first opening is disposed above the rotational axis; and   wherein the second opening is disposed below the rotational axis.    
     
     
       45. A cable disc brake according to claim 44 wherein the caliper housing is structured such that, when the caliper housing is mounted to a front fork of the bicycle, the cable support is disposed above the rotational axis.  
     
     
       46. A cable disc brake according to claim 45 wherein the caliper housing is structured such that, when the caliper housing is mounted to the front fork of the bicycle, the guide surface is disposed rearwardly of the rotational axis.  
     
     
       47. A cable disc brake according to claim 46 wherein the caliper housing is structured such that, when the caliper housing is mounted to the front fork of the bicycle, the cable support extends rearwardly of the rotational axis.  
     
     
       48. A cable disc brake according to claim 39 wherein the cable, when coupled to the cable clamp, approaches the guide surface from the opening in the cable support essentially in a straight line.  
     
     
       49. A cable disk brake according to claim 39 further comprising a torsion spring that applies a torsion force to the actuating arm relative to the caliper housing to bias the actuating arm to a brake releasing position.  
     
     
       50. A cable disc brake according to claim 49 wherein the torsion spring has an end coupled to the actuating arm.  
     
     
       51. A cable disc brake according to claim 49 wherein the torsion spring is adjustably coupled to the caliper housing.  
     
     
       52. A cable disc brake according to claim 49 wherein the torsion spring has a first end adjustably coupled to the caliper housing and a second end fixed relative to the actuating arm.  
     
     
       53. A cable disc brake according to claim 52 wherein the second end of the torsion spring is directly connected to the actuating arm.  
     
     
       54. A cable disc brake according to claim 52 wherein the caliper housing has a plurality of openings so that the first end of the torsion spring is selectively inserted into one of the plurality of openings to adjust the first end relative to the caliper housing.  
     
     
       55. A cable disk brake according to claim 39 wherein the cable support is one piece with the surface of the caliper housing from which it extends.  
     
     
       56. A cable disk brake according to claim 55 wherein the cable support comprises an elongated member.  
     
     
       57. A cable disk brake according to claim 56 wherein the elongated member forms the opening such that the opening for guiding the cable is immovable relative to the surface of the caliper housing.  
     
     
       58. A cable disc brake according to claim 39 wherein the cable support extends from a surface of the caliper housing and is not removable relative to the surface of the caliper housing.  
     
     
       59. A cable disc brake according to claim 39 wherein a straight phantom line that originates from the rotational axis intersects the first surface and the second surface.  
     
     
       60. A cable disc brake according to claim 39 wherein a circumferential width of the actuating arm measured circumferentially from one circumferential side surface of the actuating arm to an opposite circumferential side surface of the actuating arm is less than a radial length of the actuating arm measured in a straight line from the rotational axis to the location where the cable leaves the guide surface.  
     
     
       61. A cable disc brake according to claim 39 further comprising a biasing mechanism that applies a biasing force between the caliper housing and the actuating arm.  
     
     
       62. A cable disc brake according to claim 61 further comprising an adjusting mechanism that adjusts the biasing force applied between the caliper housing and the actuating arm in addition to changes of biasing force caused by rotation of the actuating arm relative to the caliper housing.  
     
     
       63. A cable disc brake according to claim 61 wherein the biasing mechanism comprises a spring.  
     
     
       64. A cable disc brake according to claim 62 wherein the biasing mechanism comprising a spring having a first end and a second end, and wherein the adjusting mechanism adjusts the biasing force by moving one of the first end and the second end relative to the other one of the first end and the second end.  
     
     
       65. A cable disc brake according to claim 64 wherein the first end of the spring is coupled relative to the caliper housing at a first position, and wherein the adjusting mechanism adjusts the biasing force by coupling the first end of the spring relative to the caliper housing at a second position different from the first position.  
     
     
       66. A cable disc brake according to claim 64 wherein the second end of the spring is coupled relative to the actuating arm at a first position, and wherein the adjusting mechanism adjusts the biasing force by coupling the second end of the spring relative to the actuating arm at a second position different from the first position.  
     
     
       67. A cable disc brake for a bicycle comprising:
 a caliper housing with a mounting bracket structured and dimensioned to be attached to a bicycle;   a first friction member movably coupled to said caliper housing between a release position and a braking position;   a second friction member coupled to said caliper housing and arranged substantially parallel to said first friction member to form a rotor receiving slot therebetween;   an actuated mechanism movably coupled to said caliper housing to move said first friction member in an axial direction from said release position towards said second friction member to said braking position, said actuated mechanism including:
 an input cam movably mounted within said caliper housing to move in a rotational direction about a longitudinal axis, but not in an axial direction, said input cam having a first camming surface with an axially extending guide member non-movably fixed thereto at said longitudinal axis, and 
 an output cam movably mounted within said caliper housing to move in the axial direction in response to rotation of said input cam, but not in the rotational direction, said output cam having a second camming surface with an axially extending bore, said guide member being at least partially disposed within said bore to ensure smooth relative movement between said input and output cams; and 
   a cable adjusting bolt coupled to said caliper housing and structured to terminate an outer casing of a brake cable and including an opening through which an inner wire of said brake cable passes.    
     
     
       68. A cable disc brake for a bicycle comprising:
 a caliper housing with a mounting bracket structured and dimensioned to be attached to a bicycle;   a first friction member movably coupled to said caliper housing between a release position and a braking position;   a second friction member coupled to said caliper housing and arranged substantially parallel to said first friction member to form a rotor receiving slot therebetween; and   an actuated mechanism movably coupled to said caliper housing to move said first friction member in an axial direction from said release position towards said second friction member to said braking position, said actuated mechanism including:
 an input cam movably mounted within said caliper housing to move in a rotational direction about a longitudinal axis, but not in an axial direction, said input cam having a first camming surface with an axially extending guide member non-movably fixed thereto at said longitudinal axis, and 
 an output cam movably mounted within said caliper housing to move in the axial direction in response to rotation of said input cam, but not in the rotational direction, said output cam having a second camming surface with an axially extending bore, said guide member being at least partially disposed within said bore to ensure smooth relative movement between said input and output cams; 
 wherein a space between said first camming surface and said second camming surface increases or decreases during operation of said actuated mechanism.  
   
     
     
       69. A cable disc brake for a bicycle comprising:
 a caliper housing with a mounting bracket structured and dimensioned to be attached to a bicycle;   a first friction member movably coupled to said caliper housing between a release position and a braking position;   a second friction member coupled to said caliper housing and arranged substantially parallel to said first friction member to form a rotor receiving slot therebetween; and   an actuated mechanism movably coupled to said caliper housing to move said first friction member in an axial direction from said release position towards said second friction member to said braking position, said actuated mechanism including:
 an input cam movably mounted within said caliper housing to move in a rotational direction about a longitudinal axis, but not in an axial direction, said input cam having a first camming surface with an axially extending guide member non-movably fixed thereto at said longitudinal axis, 
 an output cam movably mounted within said caliper housing to move in the axial direction in response to rotation of said input cam, but not in the rotational direction, said output cam having a second camming surface with an axially extending bore, said guide member being at least partially disposed within said bore to ensure smooth relative movement between said input and output cams; and 
   a cable adjusting bolt coupled to said caliper housing and structured to terminate an outer casing of a brake cable and including an opening through which an inner wire of said brake cable passes.    
     
     
       70. A cable disc brake for a bicycle comprising:
 a caliper housing with a mounting bracket structured and dimensioned to be attached to a bicycle;   a first friction member movably coupled to said caliper housing between a release position and a braking position;   a second friction member coupled to said caliper housing and arranged substantially parallel to said first friction member to form a rotor receiving slot therebetween; and   an actuated mechanism movably coupled to said caliper housing to move said first friction member from said release position towards said second friction member to said braking position, said actuated mechanism having first and second cam members movably arranged between an axially retracted position and an axially extended position with a guide member interconnecting said first and second cam members during movement between said axially retracted position and said axially extended position, said guide member being non-movable in the axial direction relative to said caliper housing,   said first cam member being rotatably mounted within said caliper housing, but non-movably mounted in the axial direction, and said second cam member being movably mounted in the axial direction but non-rotatably mounted;   wherein said first cam member has a first camming surface, wherein said second cam member has a second camming surface, and wherein a space between said first camming surface and said second camming surface increases or decreases during operation of said actuated mechanism.