Sprocket shift assembly

• US 4,127,038 A
• Filed: 08/06/1976
• Issued: 11/28/1978
• Est. Priority Date: 08/06/1976
• Status: Expired due to Term

• Current Assignee: Browning Automatic Transmission
• Original Assignee: Christopher M. Browning, David L. Browning, Gloria S. Browning, John B. Browning, Marc S. Browning, Michael C. Browning, Paul C. Browning
• Inventors: Browning, Bruce W.
• Primary Examiner(s): Wyche, Benjamin W.
• Assistant Examiner(s): Henderson, W. R.
• Application Number:
  US05/712,246
• Time in Patent Office: 844 Days
• Field of Search: 74/217 R, 74/217 B, 74/244, 74/230.18, 74/439, 74/448, 280/236, 280/237, 280/238
• US Class Current: 474/80
• CPC Class Codes: B62M 9/10 involving different-sized wheels, e.g. rear sprocket chain wheels selectively engaged by the chain, belt, or the like bicycle hubs rotatably arranged on axle B60B27/023
• CPC Class Codes: B62M 9/12 the chain, belt, or the like being laterally shiftable , e.g. using a rear derailleur
• CPC Class Codes: B62M 9/14 the wheels being laterally shiftable

Abstract

A sprocket shift assembly wherein sprockets of different diameters are arranged as a cluster on a common shaft and are coupled with a chain between driving and driven members. The chain is movable as the sprockets rotate from one of the sprockets to another by realignment of portions of the sprocket such that the chain is at all times in a positive driving relationship with the cluster.

Claims

1. A sprocket shift assembly comprising

a driving hinge;

a pair of sprocket sectors, each having at least one partial sprocket thereon lying in a first plane;

another sprocket, lying in a second plane parallel to the first plane, and having a pitch diameter that is different from the pitch diameter of the full sprocket formed by the partial sprockets;

means mounting at least one of said sprocket sectors to be movable with respect to said driving hinge such that the partial sprockets of the sprocket sectors can lie in one plane at the same time to form a full sprocket when the sprocket sectors are in predetermined meshed position relative to the driving hinge, and such that each movable mounted sprocket sector can be moved to place some partial sprocket teeth thereof in a second plane; and

means coupling the sprocket sectors to the driving hinge for rotation therewith.

2. A sprocket shift assembly as in claim 1, further including

means for releasably locking each of the sprocket sectors movable with respect to the driving hinge to prevent undesired movement thereof.

3. A sprocket shift assembly as in claim 1, further including

means biasing each sprocket sector movable with respect to the driving hinge to thereby place the partial sprockets of the sprocket sectors in the same plane.

4. A sprocket shift assembly as in claim 3, further including

means for releasably locking each of the sprocket sectors movably mounted with respect to the driving hinge to prevent undesired movement thereof.

5. A sprocket shift assembly as in claim 4, wherein

each sprocket sector movably mounted with respect to the driving hinge is pivotally connected thereto.

6. A sprocket shift assembly as in claim 2, wherein the means for releasably locking each of the movable sprocket sectors to the driving hinge comprises

a lever pivotally connected to each sprocket sector;

means biasing each lever to a locking position; and

latch means for each lever on the driving hinge, said latch means consisting of a finger projecting from the driving hinge such that the levers will be biased between the finger means and the driving hinge and will engage the finger means to prevent pivoting of the sprocket sectors with respect to said driving hinge.

7. A sprocket shift assembly as in claim 1, wherein the means for coupling the sprocket sectors to the driving hinge for rotation therewith includes

parallel grooves and lands on the driving hinge;

and

parallel grooves and lands on the sprocket sectors, the lands of the sprocket sectors fitting in the grooves of the driving hinge and the lands of the driving hinge fitting in the grooves of the sprocket sectors.

8. A sprocket shift assembly as in claim 1, further including

a one-piece full sprocket, of smaller diameter than the full sprocket formed by the sprocket sectors, coaxially mounted with respect to the full sprocket formed by partial sprockets and in a plane parallel thereto whereby movement of a sprocket sector will position some of the teeth of a partial sprocket in the plane of the smaller one-piece full sprocket.

9. A sprocket shift assembly as in claim 5, wherein the means for releasably locking each sprocket sector pivotally connected to the driving hinge comprises

a lever pivotally connected to each sprocket sector;

means biasing each lever to a locking position; and

latch means for each lever on the driving hinge said latch means consisting of a finger projecting from the driving hinge such that the levers will be biased between the finger means and the driving hinge and will engage the finger to prevent movement of the sprocket sectors with respect to said driving hinge.

10. A sprocket shift assembly as in claim 9, wherein the means for coupling the sprocket sectors to the driving hinge for rotation therewith includes

parallel grooves and lands on the driving hinge;

and

parallel grooves and lands on the sprocket sectors, the lands of the sprocket sectors fitting in the grooves of the driving hinge and the hands of the driving hinge fitting in the grooves of the sprocket sectors.

11. A sprocket shift assembly as in claim 10, further including

a one-piece full sprocket, of smaller diameter than the full sprocket formed by the sprocket sectors, coaxially mounted with respect to the full sprocket formed by partial sprockets and in a plane parallel thereto whereby pivoting of a sprocket sector will position some of the teeth of a partial sprocket in the plane of the smaller one-piece full sprocket.

12. A sprocket shift assembly as in claim 11, further including

a hub comprising a member to be rotated;

and

means coupling the driving hinge to the hub for rotation therewith.

13. A sprocket shift assembly as in claim 12, wherein the means coupling the driving hinge to the hub for rotation therewith comprises

a ratchet assembly that locks the driving hinge to the hub for rotation in one direction and that allows independent reverse rotation of the hub and driving hinge.

14. A sprocket shift assembly as in claim 1, further including means for providing a tooth spacing between each movable sprocket sector and the other sprocket lying in a second plane parallel to the first plane and having a pitch diameter that is different from the pitch diameter of the full sprocket formed by the partial sprockets, that is a multiple of the chain pitch.

15. A sprocket shift assembly as in claim 14, wherein the means for providing a tooth spacing between each movable sprocket sector and the other sprocket that is a multiple of the chain pitch comprises

a partial tooth on a movable sprocket sector that is of different length than the other teeth of said sprocket;

and

gaps adjacent to said partial tooth having a different depth than gaps adjacent to others of the teeth on said sprocket.

16. A sprocket shift assembly comprising

a driving hinge;

a pair of sprocket sectors, each having at least two partial sprockets thereon, one of said partial sprockets having a larger radius than the other and said partial sprockets lying in parallel first and second planes; and

means coupling at least one of said sprocket sectors to said driving hinge such that the smaller partial sprockets of the sprocket sectors can lie in one plane at the same time the larger partial sprockets of the sprocket sectors are in another plane to respectively form smaller and larger full sprockets and such that the same one sprocket sector can be moved to place some teeth of one partial sprocket of one radius in the plane of a partial sprocket of different radius of the other sprocket sector.

17. A sprocket shift assembly as in claim 16, wherein

the means coupling at least one of said sprocket sectors to said driving hinge includes a pivot connection.

18. A sprocket shift assembly as in claim 16, wherein

both sprocket sectors are pivotally connected to the driving hinge.

19. A sprocket shift assembly as in claim 18, further including

means for releasably locking each of the sprocket sectors movable with respect to the driving hinge to prevent undesired movement thereof.

20. A sprocket shift assembly as in claim 19, wherein the means for coupling the sprocket sectors to the driving hinge for rotation therewith includes

parallel grooves and lands on the driving hinge;

and

parallel grooves and lands on the sprocket sectors, the lands of the sprocket sectors fitting in the grooves of the driving hinge and the lands of the driving hinge fitting in the grooves of the sprocket sectors.

21. A sprocket shift assembly as in claim 20, wherein the means for releasably locking the sprocket sectors to the driving hinge comprises

a lever pivotally connected to each sprocket sector;

means biasing each lever to a locking position; and

latch means for each lever on the driving hinge, said latch means consisting of a finger projecting from the driving hinge such that the levers will be biased between the finger means and the driving hinge and will engage the finger to prevent pivoting of the sprocket sectors with respect to said driving hinge.

22. A sprocket shift assembly as in claim 21, further including

means for providing a tooth spacing between each movable sprocket sector and a partial sprocket on the other sprocket sector that is a multiple of the chain pitch.

23. A sprocket shift assembly as in claim 22, wherein the means for providing a tooth spacing between each movable sprocket sector and the other sprocket that is a multiple of the chain pitch comprises

a partial tooth on a movable sprocket sector that is of different length than the other teeth of said sprocket;

and

gaps adjacent to said partial tooth having a different depth than gaps adjacent to others of the teeth on said sprocket.

24. A sprocket shift assembly comprising

a driving hinge;

a pair of sprocket sectors, each having at least one partial sprocket thereon; and

means mounting at least one of said sprocket sectors to be movable with respect to said driving hinge such that the partial sprockets of the sprocket sectors can lie in one plane at the same time to form a full sprocket, and such that at least one sprocket sector movably mounted with respect to said driving hinge can be moved to place some partial sprocket teeth thereof in a second plane.

25. A sprocket shift assembly as in claim 24, including

another sprocket having a tooth pitch that is different from the tooth pitch of the full sprocket formed by the partial sprockets;

means mounting said other sprocket such that the teeth thereof can lie substantially in the second plane.

26. A sprocket shift assembly as in claim 24, further including

means for releasably locking each of the sprocket sectors, movable with respect to the driving hinge, to the said hinge to prevent undesired movement thereof.

27. A sprocket shift assembly as in claim 24, further including

means coupling the sprocket sectors to the driving hinge for rotation therewith.

28. A sprocket shift assembly as in claim 27, wherein

the partial sprockets lie in one plane to form a full sprocket when the sprocket sectors are fully meshed with the driving hinge.

29. A sprocket shift assembly as in claim 27, including

another sprocket having a pitch diameter that is different from the pitch diameter of the full sprocket formed by the partial sprockets;

means mounting said other sprocket such that the teeth thereof can lie substantially in the second plane.

30. A sprocket shift assembly as in claim 27, further including

means for releasably locking each of the sprocket sectors, movable with respect to the driving hinge, to the said hinge to prevent undesired movement thereof.