Multi-Speed Sprocket Assembly

Abstract

A multi-speed sprocket assembly is suggested, including at least two sprockets, with both sprockets having at least one common upshift transitional region in which, when the chain is displaced from the smaller sprocket to the larger sprocket for the purpose of shifting gears, the chain leaves the smaller sprocket, with a trailing tooth of the smaller sprocket being the last to engage between a trailing link plate pair of the chain, and moves onto the larger sprocket, with a leading tooth of the larger sprocket either being the first to engage between a first outer link plate pair or being located adjacent to a first inner link plate pair, and with at least the larger sprocket having in its upshift transitional region a double spacewidth created by omitting a tooth, which is immediately followed by the leading tooth. Only one chain link crossing from the smaller sprocket to the larger sprocket is located between the trailing chain link and the leading chain link. The chain roller of the link connection between the crossing chain link and the trailing chain link is located directly across from a rear tooth flank of the trailing tooth of the smaller sprocket. The leading tooth cooperates with a circumferential surface of a link plate of the crossing chain link using its front tooth flank, with the leading tooth being in contact with either the inner surface of an outer link plate or with the outer surface of an inner link plate of the leading chain link. In the region of the double spacewidth, the larger sprocket is embodied in such a way that the crossing chain link comes into contact with the larger sprocket only in the region of the leading tooth.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a side view of a multi-speed sprocket assembly according to one embodiment of the present invention engaged by a section of a chain;

FIG. 2 is a side view of the multi-speed sprocket assembly of FIG. 1, but in an outer link plate configuration;

FIG. 3 is a view in the radial direction (Arrow III) of the arrangement shown in FIG. 1, but with a shortened chain segment;

FIG. 4 is a view corresponding to FIG. 3, but with a configuration of FIG. 2 (arrow IV);

FIG. 5 is a perspective view of an arrangement of four relatively small sprockets, which are in turn part of a multi-speed sprocket assembly, which is otherwise not shown;

FIG. 6 is a partially sectioned perspective view at an oblique angle from the top of a sprocket of the arrangement of FIG. 5 with a nominal number of teeth of 13;

FIG. 7 is a side view with a slight inclination of the sprocket of FIG. 6, also partially sectioned;

FIG. 8 is a side view of the sprockets with a nominal number of teeth of 12 and a nominal number of teeth of 13 of FIGS. 5 to 7 with a chain section in the upshift transitional area in an inner link plate configuration similar to FIG. 1;

FIG. 9 is a view of the sprockets of FIG. 8, but in an outer link plate configuration similar to FIG. 2; and

FIG. 10 is a side view of a bicycle shifting system.

Claims

1. A multi-speed sprocket assembly for engaging a shifting chain having chain links that are formed by inner links with inner link plates and outer links with outer link plates and having link connections having chain rollers between the chain links with a distance between the axes of immediately consecutive link connections that establishes a chain pitch, the multi-speed sprocket assembly comprising: at least one larger sprocket and at least one smaller sprocket, each having teeth arranged one after the other at a distance corresponding to the chain pitch and single spacewidths formed between consecutive teeth,the two sprockets having at least one common upshift transitional region in which, when the chain is displaced from the smaller sprocket to the larger sprocket for the purpose of shifting gears, the chain leaves the smaller sprocket with a trailing tooth of the smaller sprocket being last to engage between the link plates of a trailing chain link of the chain and running onto the larger sprocket, with a leading tooth of the larger sprocket being one of first to engage between the outer link plates of a leading chain link and being located adjacent to the inner link plates of a leading chain link,at least the larger sprocket having in its upshift transitional region a double spacewidth created by the omission of a tooth, which is immediately followed by the leading tooth,only one chain link crossing from the smaller sprocket to the larger sprocket located between the trailing chain link on the smaller sprocket and the leading chain link on the larger sprocket,the chain roller of the link connection between the crossing chain link and the trailing chain link being located directly across from a rear tooth flank of the trailing tooth of the smaller sprocketwhen the leading chain link is an outer link, the leading tooth then being in contact with the inner surface of an outer link plate of the leading chain link and, with its front tooth flank, cooperating with a circumferential surface of an inner link plate of the crossing chain link,when the leading chain link is an inner link, the leading tooth then being in contact with an outer side of an inner link plate of the leading chain link and, with its front tooth flank, cooperating with a circumferential surface of an outer link plate of the crossing chain link,the double spacewidth of the larger sprocket configured such that the crossing chain link contacts the larger sprocket in the region of the leading tooth.

2. The multi-speed sprocket assembly according to claim 1, wherein the larger sprocket has a removed region forming the double spacewidth having a shape such that the larger sprocket, viewed in the axial direction, has essentially no overlap with the crossing chain link.

3. The multi-speed sprocket assembly according to claim 1, wherein the larger sprocket has a removed area forming the double spacewidth with such a shape that the larger sprocket, viewed in the axial direction, has an overlap with the crossing chain link in the form of a recess with a clearance between the recess and the crossing chain link.

4. The multi-speed sprocket assembly according to claim 3 wherein the larger sprocket has a recess in an overlap region with the link plates of the trailing chain link, but with clearance between the recess and the trailing chain link.

5. The multi-speed sprocket assembly according to claim 4, wherein the leading tooth cooperates with the link plate of the crossing chain link in the region of a tooth tip corner formed on the radially outer end of the front tooth flank.

6. The multi-speed sprocket assembly according to claim 5, wherein the leading tooth is provided with a guiding bevel for an outer link plate of the leading chain link in the region of a tooth tip corner formed on the radially outer end of the front tooth flank.

7. The multi-speed sprocket assembly according to claim 6, wherein the leading tooth is placed obliquely to substantially correspond to the path of the crossing chain link and has a thickness that substantially corresponds to the link plate thickness.

8. The multi-speed sprocket assembly according to claim 7, wherein the nominal tooth numbers of the larger sprocket and smaller sprocket have a difference of one.

9. The multi-speed sprocket assembly according to claim 1, wherein the larger sprocket has a recess in an overlap region with the link plates of the trailing chain link, but with clearance between the recess and the trailing chain link.

10. The multi-speed sprocket assembly according to claim 1, wherein the leading tooth cooperates with the link plate of the crossing chain link in the region of a tooth tip corner formed on the radially outer end of the front tooth flank.

11. The multi-speed sprocket assembly according to claim 1, wherein the leading tooth is provided with a guiding bevel for an outer link plate of the leading chain link in the region of a tooth tip corner formed on the radially outer end of the front tooth flank.

12. The multi-speed sprocket assembly according to claim 1, wherein the leading tooth is placed obliquely to substantially correspond to the path of the crossing chain link and has a thickness that substantially corresponds to the link plate thickness.

13. The multi-speed sprocket assembly according to claim 1, wherein the nominal tooth numbers of the larger sprocket and smaller sprocket have a difference of one.

14. A bicycle shifting system comprising: a driving sprocket assembly;a driven sprocket assembly;a shifting chain connecting the driving sprocket assembly and the driven sprocket assembly; anda derailleur being provided in an uptake region of the chain between the sprockets of the multi-speed sprocket assembly for deflecting and guiding the chain from one sprocket to the other to shift gears,at least one of the driven and driving sprocket assemblies including:at least one larger sprocket and at least one smaller sprocket, each having teeth arranged one after the other at a distance corresponding to the chain pitch and single spacewidths formed between consecutive teeth,the two sprockets having at least one common upshift transitional region in which, when the chain is displaced from the smaller sprocket to the larger sprocket for the purpose of shifting gears, the chain leaves the smaller sprocket with a trailing tooth of the smaller sprocket being last to engage between the link plates of a trailing chain link of the chain and running onto the larger sprocket, with a leading tooth of the larger sprocket being one of first to engage between the outer link plates of a leading chain link and being located adjacent to the inner link plates of a leading chain link,at least the larger sprocket having in its upshift transitional region a double spacewidth created by the omission of a tooth, which is immediately followed by the leading tooth,only one chain link crossing from the smaller sprocket to the larger sprocket located between the trailing chain link on the smaller sprocket and the leading chain link on the larger sprocket,the chain roller of the link connection between the crossing chain link and the trailing chain link being located directly across from a rear tooth flank of the trailing tooth of the smaller sprocket,when the leading chain link is an outer link, the leading tooth then being in contact with the inner surface of an outer link plate of the leading chain link and, with its front tooth flank, cooperating with a circumferential surface of an inner link plate of the crossing chain link,when the leading chain link is an inner link, the leading tooth then being in contact with an outer side of an inner link plate of the leading chain link and, with its front tooth flank, cooperating with a circumferential surface of an outer link plate of the crossing chain link,the double spacewidth of the larger sprocket configured such that the crossing chain link contacts the larger sprocket in the region of the leading tooth.