ACTUATION DEVICE FOR A CONTROL CABLE FOR A BICYCLE GEARSHIFT

• US 20090025504A1
• Filed: 09/19/2008
• Published: 01/29/2009
• Est. Priority Date: 02/06/2004
• Status: Active Grant

• Current Assignee: Campagnolo S.R.L.
• Original Assignee: Campagnolo S.R.L.
• Inventors: De Pretto, Andrea, Caiazzo, Marco, Dal Pra', Giuseppe
• Granted Patent: US 10,202,164 B2
• Time in Patent Office: Days
• US Class Current: 74/501.600
• CPC Class Codes: B62K 23/06 Levers
• CPC Class Codes: B62M 25/04 hand actuated
• CPC Class Codes: F16C 1/12 Arrangements for transmitting movement to or from the flexible member
• CPC Class Codes: Y10T 74/20402 Flexible transmitter [e.g., Bowden cable]
• CPC Class Codes: Y10T 74/2042 and hand operator
• CPC Class Codes: Y10T 74/20438 Single rotatable lever [e.g., for bicycle brake or derailleur]

Abstract

The described actuation device comprises a casing, intended for the attachment to the handlebar of the bicycle, a cable-winding bobbin, angularly mobile in the casing about a main axis of the device, a first driving mechanism, acting on the bobbin to rotate it in a first angular direction, a second driving mechanism, acting on the bobbin to rotate it in a second angular direction opposite the first, as well as indexer assembly for removably holding the bobbin in predetermined angular positions. In accordance with the invention, the indexer assembly comprise first countering member, to counter the rotation of the bobbin in the first direction, and second countering member, distinct from the first countering member, to counter the rotation of the bobbin in the second direction. Asymmetric operation is thus obtained which allows active actuation to be set both for upward gearshifting and for downward gearshifting.

Claims

1. Actuation device for a control cable for a bicycle gearshift, comprising:

a housing, attachable to a bicycle handlebar,

a cable-winding bobbin, angularly mobile in the housing about a main axis of the device,

a first driving mechanism, acting on the bobbin to rotate it in a first angular direction,

a second driving mechanism, acting on the bobbin to rotate it in a second angular direction opposite the first,

an indexer assembly to removably hold the bobbin in predetermined angular positions,

wherein said indexer assembly comprises;

a first countering member, to counter the rotation of the bobbin in the first direction,

a second countering member, distinct from the first countering member, to counter the rotation of the bobbin in the second direction.

2. The device of claim 1, wherein the first countering member counters the rotation of the bobbin in a different way to the second countering member.

3. The device of claim 1, wherein the first and/or the second countering member counter the rotation of the bobbin independently of the angular position of the bobbin itself.

4. A bicycle gearshift actuator comprising:

a) a housing configured for attachment to a bicycle handlebar;

b) a shaft that is carried by the housing;

c) a shank having a central opening and opposed flat faces;

d) a bobbin that has a central opening mounted adjacent the shank and defines a connection point for a gear shift cable, the bobbin and shank are positioned for rotation about the shaft;

e) a first lever operatively connected to the shank and bobbin and rotating the shank and bobbin in a first direction;

f) a second lever operatively connected to the shank and bobbin and rotating the shank and bobbin in a second direction; and

g) an indexer assembly having a first control portion that limits the rotation of the bobbin in the first direction and a second control portion that limits the rotation of the bobbin in the second direction.

5. The actuator of claim 4, wherein the indexer assembly comprises at least one ball engaged both with a stationary member integral with the housing and with a rotating member integral in rotation with the bobbin;

the first control portion comprises a first countering spring that acts on the ball to keep the ball in a stop position wherein the ball makes the stationary member and the rotating member integral in rotation;

the second control portion comprises a second countering spring that acts upon the ball to keep it in the stop position.

6. The actuator of claim 5, wherein a rotation of the bobbin in a first angular direction biases the ball away from the stop position, in contrast to the first countering spring.

7. The actuator of claim 5, wherein a rotation of the bobbin in a second angular direction biases the ball away from the stop position, in contrast to the second countering spring.

8. The actuator of claim 5, wherein the indexer assembly comprises a ball-carrying disc, mounted in the housing and provided with at least one radial groove, said ball being mounted in said radial groove so that the ball is thrusted radially outwards by the first countering spring, the groove being open on at least one side of the ball-carrying disc and having a depth such that the ball projects in the axial direction from the ball-carrying disc;

the indexer assembly comprises a first indexing disc, mounted in the housing in an interfacing position adjacent to the ball-carrying disc, towards the side thereof from which the ball projects, and provided with a recess arranged according to a pattern that comprises stop zones and sliding zones alternating with each other;

one of the ball-carrying disc and the first indexing disc is located in the stationary member, being mounted integral in rotation with the bobbin, whereas the other of them is located in the rotating member, being mounted locked in rotation with the housing;

the second countering spring is mounted in the housing so as to axially bias the first indexing disc and the ball-carrying disc one against the other;

the ball, projecting axially from the groove on the ball-carrying disc, is engaged in the recess on the first indexing disc.

9. The actuator of claim 8, wherein an intermediate of the stop zones is defined by a stop wall orientated according to a stop direction and by a sliding wall orientated according to a sliding direction, the stop direction and sliding direction of the same stop zone defining an acute angle that does not enclose the main axis of the device.

10. The actuator of claim 9, wherein a sliding wall extends along the sliding direction from the stop zone for the entire adjacent sliding zone.

11. The actuator of claim 9, wherein the stop walls are fitted to the sliding walls in a succession that forms an outer peripheral margin of the recess on the indexing disc.

12. The actuator of claim 11 wherein the recess on the indexing disc is defined towards the inside by an inner peripheral margin corresponding to the outer peripheral margin.

13. The actuator of claim 11 wherein the recess on the indexing disc is not defined towards the inside by any inner peripheral margin.

14. Device according to claim 8, wherein the groove in the ball-carrying disc is open on both sides of such a disc and has a depth such that the ball projects in the axial direction from the ball-carrying disc, from both sides thereof;

wherein

the indexer assembly also comprises a second indexing disc integral in rotation with the first indexing disc, mounted in the housing in an interfacing position adjacent to the ball-carrying disc on the opposite side with respect to the first indexing disc and provided with a recess specularly corresponding to that of the first indexing disc; and

wherein

the ball, projecting axially from the groove on the ball-carrying disc, is engaged both in the recess on the first indexing disc, and in the recess on the second indexing disc.

15. The actuator of claim 8, wherein the stationary member comprises the ball-carrying disc and the rotating member comprises the first indexing disc.

16. The actuator of claim 8, wherein the rotating member comprises the ball-carrying disc and the stationary member comprises the first indexing disc.

17. The actuator of claim 5, wherein the indexer assembly comprises a further ball, engaged both with the stationary member and with the rotating member.

18. The actuator of claim 17, wherein the indexer assembly comprises a further first countering spring that acts upon the further ball to keep it in a stop position wherein it makes the rotating member and the stationary member integral in rotation.

19. The actuator of claim 17, wherein a rotation of the bobbin in the first angular direction biases the further ball away from the stop position, in contrast to the first countering spring or to the further first countering spring.

20. The actuator of claim 17, wherein a rotation of the bobbin in the second angular direction biases the further ball away from the stop position, in contrast to the second countering spring.

21. The actuator of claim 17, wherein:

the indexer assembly comprises a ball-carrying disc, mounted in the housing and provided with at least two radial grooves, in each of said grooves being mounted one of said balls so that each ball is thrusted radially outwards by the respective first countering spring, the grooves being open on at least one side of the ball-carrying disc and having a depth such that the balls project in the axial direction from the ball-carrying disc;

the indexer assembly comprises a first indexing disc, mounted in the housing in an interfacing position adjacent to the ball-carrying disc, towards the side thereof from which the balls project, and provided with two recesses that are the same as each other, arranged according to patterns that comprise stop zones and sliding zones alternating with each other; and

wherein;

one of the ball-carrying disc and the first indexing disc is located in the rotating member, being mounted integral in rotation with the bobbin, whereas the other of them is located in the stationary member, being mounted locked in rotation with the housing;

the second countering spring is mounted in the housing so as to axially bias the first indexing disc and the ball-carrying disc one against the other;

the balls, projecting axially from the grooves on the ball-carrying disc, are respectively engaged in the two recesses on the first indexing disc.

22. The actuator of claim 21, wherein an intermediate of the stop zones is defined by a stop wall orientated according to a stop direction and by a sliding wall orientated according to a sliding direction, the stop direction and sliding direction of the same stop zone defining an acute angle that does not enclose the main axis of the device.

23. The actuator of claim 21, wherein a sliding wall extends along the sliding direction from any of the stop zone for the entire adjacent sliding zone.

24. The actuator of claim 22, wherein a sliding wall extends along the sliding direction from any of the stop zone for the entire adjacent sliding zone and wherein the stop walls are fitted to the sliding walls in a succession that forms an outer peripheral margin of the recess on the indexing disc.

25. The actuator of claim 24, wherein the recess on the indexing disc is defined towards the inside by an inner peripheral margin corresponding to the outer peripheral margin.

26. The actuator of claim 24, wherein the recess on the indexing disc is not defined towards the inside by any inner peripheral margin.

27. The actuator of claim 21, wherein:

the grooves in the ball-carrying disc are open on both sides of such a disc and have a depth such that the balls project in the axial direction from the ball-carrying disc, from both sides thereof;

wherein

the indexer assembly also comprises a second indexing disc integral in rotation with the first indexing disc, mounted in the housing in an interfacing position adjacent to the ball-carrying disc on the opposite side with respect to the first indexing disc and provided with a recess specularly corresponding to that of the first indexing disc; and

wherein

the balls, projecting axially from the grooves on the ball-carrying disc, are engaged both in the recess on the first indexing disc, and in the recess on the second indexing disc.

28. The actuator of claim 21, wherein the stationary member comprises the ball-carrying disc and the rotating member comprises the first indexing disc.

29. The actuator of claim 21, wherein the rotating member comprises the ball-carrying disc and the stationary member comprises the first indexing disc.

30. The actuator of claim 5, wherein the first countering spring is a helical spring compressed between the ball and an abutment on the ball-carrying disc.

31. The actuator of claim 8, wherein the first countering spring is a flat spring mounted on the ball-carrying disc and acting on the ball.

32. The actuator of claim 8, wherein the first countering spring is a single flat spring mounted on the ball-carrying disc and acting on the two balls.

33. The actuator of claim 8, wherein the second countering spring is a Belleville washer, arranged coaxially to the ball-carrying disc and to the first indexing disc.

34. The actuator of claim 8, wherein the second countering spring is an elastically deformable elastomeric ring, arranged coaxially to the ball-carrying disc and to the first indexing disc.

35. The actuator of claim 5, wherein the first countering spring applies on the ball or on the balls a force in the radial direction that is less than 1/20 of the force that the second countering spring applies on the ball or on the balls in the axial direction.