TWI903410B - Improved structure of the bicycle sprocket - Google Patents

Abstract

An improved structure of a bicycle sprocket comprises: a first sprocket having a first inner ring portion, a first connecting portion, and a first outer ring tooth portion; the first inner ring portion is located radially inward of the first outer ring tooth portion; the first connecting portion is located between the first inner ring portion and the first outer ring tooth portion, with both ends respectively connected to the first inner ring portion and the first outer ring tooth portion; and a second sprocket, with an outer diameter smaller than the first sprocket, positioned on one side axially of the first sprocket, and there being no other sprocket between the first sprocket and the second sprocket; the second sprocket having a second inner ring portion, a second connecting portion, and a second outer ring tooth portion; the second inner ring portion is located radially inward of the second outer ring tooth portion; the second connecting portion is located between the second inner ring portion and the second outer ring tooth portion, with both ends respectively connected to the first inner ring portion and the first outer ring tooth portion; wherein the first inner ring portion of the first sprocket is fitted to the second inner ring portion of the second sprocket, and the first outer ring tooth portion of the first sprocket is axially spaced apart from the second outer ring tooth portion of the second sprocket by a first predetermined distance.

Description

Improvement of bicycle chainring structure

This invention relates to bicycle chainrings, and more particularly to an improved bicycle chainring structure that prevents chainring wobble during movement and achieves weight reduction.

Note that to allow riders to adjust the bicycle's transmission efficiency according to different riding conditions, most bicycles are equipped with a freewheel and derailleurs. The freewheel is a structure formed by a combination of chainrings of different sizes. Common chainrings move the chain to different chainrings by changing their position. Because the chainrings are of different sizes, the gear ratio between the front and rear chainrings changes, causing a change in pedaling weight, thus achieving the effect of shifting gears. Common combinations include a front-derailleur system with a front freewheel and a front derailleur; a rear-derailleur system with a rear freewheel and a rear derailleur; or a multi-derailleur system that combines both front and rear freewheels and derailleurs.

In order to ensure smooth movement of the chain between the gears, the fixing structure between the gears is crucial. The conventional gear fixing structure mainly involves adding washers between the gears and fixing them to the gears through welding, locking, or screwing. The washers serve to separate the gears while simultaneously stabilizing the gear structure. However, its drawback is that there is no direct contact between the gears; therefore, if the washers are not securely locked to the gears, the gears may still wobble as the chain moves across them. On the other hand, adding washers between the chainrings undoubtedly increases the overall weight of the freewheel. The more chainrings a freewheel has, the more washers are needed, leading to an excessively heavy freewheel structure and affecting the overall weight of the bicycle. Therefore, providing a bicycle chainring structure that solves both the chainring fixing problem and the washer weight problem is one of the urgent issues that manufacturers and researchers in related fields need to address.

The main objective of this invention is to provide an improvement to the bicycle sprocket structure, which can prevent sprocket wobble caused by chain movement.

Another objective of this invention is to provide an improvement to the bicycle chainring structure, which allows for an overall reduction in the weight of the chainring structure.

To achieve the aforementioned objective, the present invention provides an improved bicycle sprocket structure, comprising: a first sprocket having a first inner ring portion, a first connecting portion, and a first outer ring tooth portion; the first inner ring portion being radially inward of the first outer ring tooth portion; the first connecting portion being disposed between the first inner ring portion and the first outer ring tooth portion, with its two ends respectively connected to the first inner ring portion and the first outer ring tooth portion; and a second sprocket having an outer diameter smaller than that of the first sprocket, disposed on one axial side of the first sprocket, and the first sprocket and the second sprocket... There is no other toothed disc between the two discs; the second toothed disc has a second inner ring portion, a second connecting portion, and a second outer ring tooth portion; the second inner ring portion is radially inward of the second outer ring tooth portion; the second connecting portion is disposed between the second inner ring portion and the second outer ring tooth portion, with its two ends respectively connected to the first inner ring portion and the first outer ring tooth portion; wherein, the first inner ring portion of the first toothed disc fits against the second inner ring portion of the second toothed disc, and the first outer ring tooth portion of the first toothed disc and the second outer ring tooth portion of the second toothed disc are axially spaced by a first predetermined distance.

In one embodiment, the first inner ring portion and the first outer ring tooth portion of the first gear disk are generally parallel; the first connecting portion is inclined relative to the first inner ring portion and the first outer ring tooth portion, causing the first inner ring portion to shift towards the second gear disk relative to the first outer ring tooth portion; wherein the second inner ring portion, the second connecting portion, and the second outer ring tooth portion of the second gear disk are coplanar.

In one embodiment, the second inner ring portion and the second outer ring tooth portion of the second gear are generally parallel; the second connecting portion is inclined relative to the second inner ring portion and the second outer ring tooth portion, causing the second inner ring portion to shift towards the first gear with respect to the second outer ring tooth portion; wherein the first inner ring portion, the first connecting portion, and the first outer ring tooth portion of the first gear are coplanar.

In one embodiment, the first inner ring portion and the first outer ring tooth portion of the first gear are generally parallel; the first connecting portion is inclined relative to the first inner ring portion and the first outer ring tooth portion, causing the first inner ring portion to shift towards the second gear relative to the first outer ring tooth portion; wherein the second inner ring portion and the second outer ring tooth portion of the second gear are generally parallel; the second connecting portion is inclined relative to the second inner ring portion and the second outer ring tooth portion, causing the second inner ring portion to shift towards the first gear relative to the second outer ring tooth portion.

In one embodiment, the first connecting portion and the second connecting portion form an angle not equal to 0.

In one embodiment, a third toothed disc, the outer diameter of which is smaller than that of the second toothed disc, is disposed on one side of the second toothed disc opposite to the first toothed disc; the third toothed disc has a third inner ring portion, a third connecting portion, and a third outer ring tooth portion; the third inner ring portion is radially inward of the third outer ring tooth portion; the third connecting portion is disposed between the third inner ring portion and the third outer ring tooth portion, with its two ends respectively connected to the third inner ring portion and the third outer ring tooth portion; wherein the third The third inner ring portion and the third outer ring tooth portion of the gear set are generally parallel; the third connecting portion is inclined relative to the third inner ring portion and the third outer ring tooth portion, causing the third inner ring portion to shift towards the second gear set relative to the third outer ring tooth portion; wherein, the third inner ring portion of the third gear set fits against the second inner ring portion of the second gear set, and the third outer ring tooth portion of the third gear set and the second outer ring tooth portion of the second gear set are axially spaced by a second predetermined distance.

In one embodiment, the second connecting portion and the third connecting portion form an angle that is not equal to 0.

In one embodiment, a maximum toothed disc is further included, the outer diameter of which is larger than that of the first toothed disc, and is disposed on one side of the first toothed disc opposite to the second toothed disc; the maximum toothed disc has a maximum inner ring portion, a maximum connecting portion, and a maximum outer ring tooth portion; the maximum inner ring portion is radially inward of the maximum outer ring tooth portion; the maximum connecting portion is disposed on the maximum inner ring portion and the maximum outer ring tooth portion. Between the large outer ring teeth, both ends are respectively connected to the largest inner ring tooth and the largest outer ring tooth; wherein the largest inner ring tooth and the largest outer ring tooth of the largest tooth disk are generally parallel; the largest connecting portions are inclined relative to the largest inner ring tooth and the largest outer ring tooth, causing the largest inner ring tooth to shift towards the first tooth disk relative to the largest outer ring tooth.

In one embodiment, the largest inner ring portion of the largest gear disk is fitted against the first outer ring portion of the first gear disk, and the largest outer ring portion of the largest gear disk and the first outer ring portion of the first gear disk are axially spaced by a third predetermined distance.

In one embodiment, a non-zero angle is formed between the largest connecting portion of the largest gear and the first outer ring tooth portion of the first gear.

The following are preferred embodiments based on the purposes, effects, and structural configurations disclosed in this invention, with detailed explanations and accompanying diagrams.

S: Disc set

S0: Largest disc

S1, S21, S31, S41, S51: First toothed disc

S2, S22, S32, S42, S52: Second tooth disc

S3, S53: Third toothed disc

11,211,311,411,511: First Inner Ring

12,212,312,412,512: First connecting part

13, 213, 313, 413, 513: First outer ring teeth

130: First outer ring tooth

21, 221, 321, 421, 521: Second Inner Ring

22,222,322,422,522: Second connecting part

23,223,323,423,523: Second outer ring teeth

230: Second outer ring tooth

31,531: Third Inner Ring

32,532: Third connecting part

33,533: Third outer ring teeth

330: Third outer ring tooth

41: Maximum inner ring

42: Maximum Connector

43: Largest outer ring teeth

430: Maximum outer ring tooth

Figure 1 is a perspective view of a first preferred embodiment of the present invention.

Figure 2 is a partially exploded view of the first preferred embodiment of the present invention.

Figure 3 is a cross-sectional view of the first preferred embodiment of the present invention.

Figure 4 is a cross-sectional schematic diagram of a second preferred embodiment of the present invention.

Figure 5 is a cross-sectional schematic diagram of a third preferred embodiment of the present invention.

Figure 6 is a cross-sectional schematic diagram of the fourth preferred embodiment of the present invention.

Figure 7 is a cross-sectional schematic diagram of the fifth preferred embodiment of the present invention.

Referring to Figure 1, a preferred embodiment of the present invention provides an improvement in the bicycle chainring structure, primarily comprising a chainring assembly S. This chainring assembly S is mounted on a bicycle (not shown) and engages with a chain (not shown). In this embodiment, the chainring assembly S is a rear chainring assembly, mounted on a rear wheel hub of the bicycle (not shown). In another embodiment, the chainring assembly may be a front chainring assembly, mounted on a crank of the bicycle. In this embodiment, the chainring assembly S includes at least a maximum chainring S0, a first chainring S1, a second chainring S2, and a third chainring S3.

Referring to Figures 2 and 3, the first toothed disc S1 includes a first inner ring portion 11, a plurality of first connecting portions 12, and a first outer ring tooth portion 13. The first inner ring portion 11 is located radially inward of the first outer ring tooth portion 13. The first connecting portions 12 are formed between the first inner ring portion 11 and the first outer ring tooth portion 13, with their two ends respectively connected to the first inner ring portion 11 and the first outer ring tooth portion 13. The outer peripheral surface of the first outer ring tooth portion 13 has a plurality of first outer ring teeth 130 for the chain to mesh with. The first inner ring portion 11 and the first outer ring tooth portion 13 are generally parallel, and the first connecting portions 12 are inclined relative to the first inner ring portion 11 and the first outer ring tooth portion 13, causing the first inner ring portion 11 to shift relative to the first outer ring tooth portion 13 towards the second toothed disc S2.

The second toothed disc S2 is disposed on one side of the first toothed disc S1, and its outer diameter is smaller than that of the first toothed disc S1. The second toothed disc S2 includes a second inner ring portion 21, a plurality of second connecting portions 22, and a second outer ring tooth portion 23. The second inner ring portion 21 is located radially inward of the second outer ring tooth portion 23. The second connecting portions 22 are formed between the second inner ring portion 21 and the second outer ring tooth portion 23, with their two ends respectively connected to the second inner ring portion 21 and the second outer ring tooth portion 23. The outer peripheral surface of the second outer ring tooth portion 23 has a plurality of second outer ring teeth 230 for chain engagement. The number of the second outer ring teeth 230 is less than the number of the first outer ring teeth 130.

In this case, the second inner ring portion 21, the second connecting portions 22, and the second outer ring tooth portion 23 of the second toothed disc S2 are coplanar, meaning that the second connecting portions 22 are not inclined relative to the second inner ring portion 21 and the second outer ring tooth portion 23, and the second inner ring portion 21 is not offset relative to the second outer ring tooth portion 23. Therefore, when the second gear S2 is disposed on one side of the first gear S1, a non-zero angle is formed between the first connecting portion 12 of the first gear S1 and the second connecting portion 22 of the second gear S2, causing the first inner ring portion 11 of the first gear S1 to fit against the second inner ring portion 21 of the second gear S2, and the first outer ring tooth portion 13 of the first gear S1 and the second outer ring tooth portion 23 of the second gear S2 are separated by a first predetermined distance.

The third toothed disc S3 is disposed on the side of the second toothed disc S2 away from the first toothed disc S1, such that the third toothed disc S3 and the first toothed disc S1 are located on opposite sides of the second toothed disc S2, and the outer diameter of the third toothed disc S3 is smaller than the outer diameter of the second toothed disc S2. The third toothed disc S3 includes a third inner ring portion 31, a plurality of third connecting portions 32, and a third outer ring tooth portion 33. The third inner ring portion 31 is located radially inward of the third outer ring tooth portion 33. The third connecting portions 32 are formed between the third inner ring portion 31 and the third outer ring tooth portion 33, with their two ends respectively connected to the third inner ring portion 31 and the third outer ring tooth portion 33. The outer peripheral surface of the third outer ring tooth portion 33 has a plurality of third outer ring teeth 330 for the chain to mesh with. The number of the third outer ring teeth 330 is less than the number of the second outer ring teeth 230. The third inner ring portion 31 and the third outer ring tooth portion 33 are generally parallel, and the third connecting portions 32 are inclined relative to the third inner ring portion 31 and the third outer ring tooth portion 33, so that the third inner ring portion 31 is offset relative to the third outer ring tooth portion 33 towards the second toothed disc S2. Therefore, when the third gear S3 is connected to the second gear S2, a non-zero angle is formed between the third connecting portion 32 of the third gear S3 and the second connecting portion 22 of the second gear S2, causing the third inner ring portion 31 of the third gear S3 to fit against the second inner ring portion 21 of the second gear S2, and the third outer ring tooth portion 33 of the third gear S3 and the second outer ring tooth portion 23 of the second gear S2 are separated by a second predetermined distance.

In this embodiment, the gear set S further includes a maximum gear S0, disposed on one side of the first gear S1 opposite to the second gear S2, such that the maximum gear S0 and the second gear S2 are located on opposite sides of the first gear S1, and the outer diameter of the maximum gear S0 is larger than the outer diameter of the first gear S1. The maximum gear S0 has a maximum inner ring portion 41, a plurality of maximum connecting portions 42, and a maximum outer ring tooth portion 43. The maximum inner ring portion 41 is located radially inward of the maximum outer ring tooth portion 43. The largest connecting portions 42 are formed between the largest inner ring portion 41 and the largest outer ring tooth portion 43, with their two ends respectively connected to the largest inner ring portion 41 and the largest outer ring tooth portion 43. The outer peripheral surface of the largest outer ring tooth portion 43 has a plurality of largest outer ring teeth 430 for the chain to mesh with. The number of the largest outer ring teeth 430 is greater than the number of the first outer ring teeth 130. The largest inner ring portion 41 and the largest outer ring tooth portion 43 are generally parallel, and the largest connecting portions 42 are inclined relative to the largest inner ring portion 41 and the largest outer ring tooth portion 43, so that the largest inner ring portion 41 is offset relative to the largest outer ring tooth portion 43 towards the first toothed disc S1. When the largest gear S0 is connected to the first gear S1, the largest connecting portion 42 of the largest gear S0 and the first outer ring tooth portion 13 of the first gear S1 form an angle not equal to 0, causing the largest inner ring portion 41 of the largest gear S0 to fit against the first outer ring tooth portion 13 of the first gear S1, and the largest outer ring tooth portion 43 of the largest gear S0 and the first outer ring tooth portion 13 of the first gear S1 are separated by a third predetermined distance.

Although the above embodiments disclose the structure of the curved first toothed disc S1, the third toothed disc S3 combined with the uncurved second toothed disc S2, and the curved largest toothed disc S0 combined with the first toothed disc S1, the application of the present invention is not limited thereto.

Referring to Figure 4, a second preferred embodiment of the present invention discloses a gear assembly (not shown) comprising at least a first gear S21 and a second gear S22. The first gear S21 has a first inner ring portion 211, a first connecting portion 212, and a first outer ring tooth portion 213; the first inner ring portion 211 is located radially inward of the first outer ring tooth portion 213; the first connecting portion 212 is disposed between the first inner ring portion 211 and the first outer ring tooth portion 213, with its two ends respectively connected to the first inner ring portion 211 and the first outer ring tooth portion 213. The second toothed disc S22 has an outer diameter smaller than that of the first toothed disc S21, and is disposed on one axial side of the first toothed disc S21. There is no other toothed disc between the first toothed disc S21 and the second toothed disc S22. The second toothed disc S22 has a second inner ring portion 221, a second connecting portion 222, and a second outer ring tooth portion 223. The second inner ring portion 221 is located radially inward of the second outer ring tooth portion 223. The second connecting portion 222 is disposed between the second inner ring portion 221 and the second outer ring tooth portion 223, and its two ends are respectively connected to the second inner ring portion 221 and the second outer ring tooth portion 223. In this configuration, the first inner ring portion 211 and the first outer ring tooth portion 213 of the first toothed disc S21 are generally parallel; the first connecting portion 212 is inclined relative to the first inner ring portion 211 and the first outer ring tooth portion 213, causing the first inner ring portion 211 to shift relative to the first outer ring tooth portion 213 towards the second toothed disc S22. The second inner ring portion 221, the second connecting portion 222, and the second outer ring tooth portion 223 of the second toothed disc S22 are coplanar. Therefore, when the first gear plate S21 is connected to the second gear plate S22, the first inner ring portion 211 of the first gear plate S21 is in contact with the second inner ring portion 221 of the second gear plate S22, and the first outer ring tooth portion 213 of the first gear plate S21 and the second outer ring tooth portion 223 of the second gear plate S22 are axially spaced apart by a distance.

Referring to Figure 5, a third preferred embodiment of the present invention discloses a gear set (not shown) comprising at least a first gear set S31 and a second gear set S32. The first gear set S31 has a first inner ring portion 311, a first connecting portion 312, and a first outer ring tooth portion 313; the first inner ring portion 311 is located radially inward of the first outer ring tooth portion 313; the first connecting portion 312 is disposed between the first inner ring portion 311 and the first outer ring tooth portion 313, with its two ends respectively connected to the first inner ring portion 311 and the first outer ring tooth portion 313. The second toothed disc S32 has an outer diameter smaller than that of the first toothed disc S31, and is disposed on one axial side of the first toothed disc S31. There is no other toothed disc between the first toothed disc S31 and the second toothed disc S32. The second toothed disc S32 has a second inner ring portion 321, a second connecting portion 322, and a second outer ring tooth portion 323; the second inner ring portion 321 is located radially inward of the second outer ring tooth portion 323. The second connecting portion 322 is disposed between the second inner ring portion 321 and the second outer ring tooth portion 323, and its two ends are respectively connected to the second inner ring portion 321 and the second outer ring tooth portion 323. In the first gear plate S31, the first inner ring portion 311, the first connecting portion 312, and the first outer ring tooth portion 313 are coplanar. The second inner ring portion 321 and the second outer ring tooth portion 323 of the second gear plate S32 are generally parallel; the second connecting portion 322 is inclined relative to the second inner ring portion 321 and the second outer ring tooth portion 323, so that the second inner ring portion 321 is offset relative to the second outer ring tooth portion 323 in a direction closer to the first gear plate S31. Therefore, when the first gear plate S31 is connected to the second gear plate S32, the first inner ring portion 311 of the first gear plate S31 is in contact with the second inner ring portion 321 of the second gear plate S32, and the first outer ring tooth portion 313 of the first gear plate S31 and the second outer ring tooth portion 323 of the second gear plate S32 are axially spaced apart by a distance.

Referring to Figure 6, a fourth preferred embodiment of the present invention discloses a gear set (not shown) comprising at least a first gear set S41 and a second gear set S42. The first gear set S41 has a first inner ring portion 411, a first connecting portion 412, and a first outer ring tooth portion 413; the first inner ring portion 411 is located radially inward of the first outer ring tooth portion 413; the first connecting portion 412 is disposed between the first inner ring portion 411 and the first outer ring tooth portion 413, with its two ends respectively connected to the first inner ring portion 411 and the first outer ring tooth portion 413. The second toothed disc S42 has an outer diameter smaller than that of the first toothed disc S41, and is disposed on one axial side of the first toothed disc S41. There is no other toothed disc between the first toothed disc S41 and the second toothed disc S42. The second toothed disc S42 has a second inner ring portion 421, a second connecting portion 422, and a second outer ring tooth portion 423. The second inner ring portion 421 is located radially inward of the second outer ring tooth portion 423. The second connecting portion 422 is disposed between the second inner ring portion 421 and the second outer ring tooth portion 423, and its two ends are respectively connected to the second inner ring portion 421 and the second outer ring tooth portion 423. In this configuration, the first inner ring portion 411 and the first outer ring tooth portion 413 of the first toothed disc S41 are generally parallel; the first connecting portion 412 is inclined relative to the first inner ring portion 411 and the first outer ring tooth portion 413, causing the first inner ring portion 411 to shift relative to the first outer ring tooth portion 413 towards the second toothed disc S42. Similarly, the second inner ring portion 421 and the second outer ring tooth portion 423 of the second toothed disc S42 are generally parallel; the second connecting portion 422 is inclined relative to the second inner ring portion 421 and the second outer ring tooth portion 423, causing the second inner ring portion 421 to shift relative to the second outer ring tooth portion 423 towards the first toothed disc S41. Therefore, when the first gear plate S41 is connected to the second gear plate S42, the first inner ring portion 411 of the first gear plate S41 is in contact with the second inner ring portion 421 of the second gear plate S42, and the first outer ring tooth portion 413 of the first gear plate S41 and the second outer ring tooth portion 423 of the second gear plate S42 are axially spaced apart by a distance.

Referring to Figure 7, a fifth preferred embodiment of the present invention discloses a toothed disc assembly (not shown) comprising at least a first toothed disc S51, a second toothed disc S52, and a third toothed disc S53. The first toothed disc S51 has a first inner ring portion 511, a first connecting portion 512, and a first outer ring tooth portion 513; the first inner ring portion 511 is located radially inward of the first outer ring tooth portion 513; the first connecting portion 512 is disposed between the first inner ring portion 511 and the first outer ring tooth portion 513, with its two ends respectively connected to the first inner ring portion 511 and the first outer ring tooth portion 513. The second toothed disc S52 has an outer diameter smaller than that of the first toothed disc S51, and is disposed on one axial side of the first toothed disc S51. There is no other toothed disc between the first toothed disc S51 and the second toothed disc S52. The second toothed disc S52 has a second inner ring portion 521, a second connecting portion 522, and a second outer ring tooth portion 523. The second inner ring portion 521 is located radially inward of the second outer ring tooth portion 523. The second connecting portion 522 is disposed between the second inner ring portion 521 and the second outer ring tooth portion 523, and its two ends are respectively connected to the second inner ring portion 521 and the second outer ring tooth portion 523. The third toothed disc S53 has an outer diameter smaller than that of the second toothed disc S52, and is disposed on the side of the second toothed disc S52 opposite to the first toothed disc S51. There is no other toothed disc between the third toothed disc S53 and the second toothed disc S52. The third toothed disc S53 has a third inner ring portion 531, a third connecting portion 532, and a third outer ring tooth portion 533; the third inner ring portion 531 is located radially inward of the third outer ring tooth portion 533. The third connecting portion 532 is disposed between the third inner ring portion 531 and the third outer ring tooth portion 533, with its two ends connected to the third inner ring portion 531 and the third outer ring tooth portion 533, respectively. The first inner ring portion 511 and the first outer ring tooth portion 513 of the first toothed disc S51 are generally parallel; the first connecting portion 512 is inclined relative to the first inner ring portion 511 and the first outer ring tooth portion 513, causing the first inner ring portion 511 to shift relative to the first outer ring tooth portion 513 towards the second toothed disc S52. The second inner ring portion 521, the second connecting portion 522, and the second outer ring tooth portion 523 of the second toothed disc S52 are coplanar. The third inner ring portion 531 and the third outer ring tooth portion 533 of the third toothed disc S53 are generally parallel. The third connecting portion 532 is inclined relative to the third inner ring portion 531 and the third outer ring tooth portion 533, so that the third inner ring portion 531 is offset relative to the third outer ring tooth portion 533 in a direction closer to the second toothed disc S22. Therefore, when the first gear plate S51 and the third gear plate S53 are connected to the second gear plate S52, the first inner ring portion 511 of the first gear plate S51 and the third inner ring portion 531 of the third gear plate S53 are respectively abutted against the opposite sides of the second inner ring portion 221 of the second gear plate S52, and the first outer ring tooth portion 513 of the first gear plate S51 and the third outer ring tooth portion 533 of the third gear plate S53 are respectively axially spaced from the second outer ring tooth portion 523 of the second gear plate S52.

As can be seen from the above embodiments, any toothed disc structure comprising at least two connected discs and at least one disc bent relative to the other is within the scope of the invention.

In summary, the improved bicycle chainring structure provided by this invention, through the curved connection structure of the chainring, causes the inner and outer ring teeth of the chainring to offset each other, thereby making the outer ring teeth of adjacent chainrings adjacent to each other. In other words, adjacent chainrings of this invention can be directly locked together without the need for additional spacers, thus solving the problem of chainring wobbling caused by chain movement in conventional chainring structures. On the other hand, this invention enables the gear set to maintain the distance between the gear sets even without spacers. Therefore, compared to conventional gear set structures that require additional spacer support, this invention effectively achieves overall weight reduction in the gear set structure.

The above embodiments are merely illustrative of the technology and effects of the present invention and are not intended to limit the invention. Any person skilled in the art may modify and change the above embodiments without departing from the technical principles and spirit of the present invention; therefore, the scope of protection of the present invention shall be as described in the patent application below.

S0: Largest toothed disc S1: First toothed disc S2: Second toothed disc S3: Third toothed disc 11: First inner ring section 12: First connecting section 13: First outer ring toothed section 21: Second inner ring section 22: Second connecting section 23: Second outer ring toothed section 31: Third inner ring section 32: Third connecting section 33: Third outer ring toothed section 41: Largest inner ring section 42: Largest connecting section 43: Largest outer ring toothed section

Claims (10)

An improvement to a bicycle sprocket structure includes: a first sprocket having a first inner ring portion, a first connecting portion, and a first outer ring tooth portion; the first inner ring portion being radially inward of the first outer ring tooth portion; the first connecting portion being disposed between the first inner ring portion and the first outer ring tooth portion, with its two ends respectively connected to the first inner ring portion and the first outer ring tooth portion; and A second toothed disk, with an outer diameter smaller than that of the first toothed disk, is disposed on one axial side of the first toothed disk, and there is no other toothed disk between the first and second toothed disks; the second toothed disk has a second inner ring portion, a second connecting portion, and a second outer ring tooth portion; the second inner ring portion is radially inward of the second outer ring tooth portion; the second connecting portion is disposed between the second inner ring portion and the second outer ring tooth portion, and its two ends are respectively connected to the first inner ring portion and the first outer ring tooth portion; The first inner ring portion of the first gear plate is fitted to the second inner ring portion of the second gear plate, and the first outer ring teeth of the first gear plate and the second outer ring teeth of the second gear plate are axially spaced by a first predetermined distance. The improved bicycle chainring structure as described in claim 1, wherein the first inner ring portion and the first outer ring tooth portion of the first chainring are generally parallel; the first connecting portion is inclined relative to the first inner ring portion and the first outer ring tooth portion, such that the first inner ring portion is offset relative to the first outer ring tooth portion in a direction closer to the second chainring; wherein the second inner ring portion, the second connecting portion and the second outer ring tooth portion of the second chainring are coplanar. The improved bicycle chainring structure as described in claim 1, wherein the second inner ring portion and the second outer ring tooth portion of the second chainring are generally parallel; the second connecting portion is inclined relative to the second inner ring portion and the second outer ring tooth portion, such that the second inner ring portion is offset relative to the second outer ring tooth portion in a direction closer to the first chainring; wherein the first inner ring portion, the first connecting portion and the first outer ring tooth portion of the first chainring are coplanar. The improved bicycle chainring structure as described in claim 1, wherein the first inner ring portion and the first outer ring tooth portion of the first chainring are generally parallel; the first connecting portion is inclined relative to the first inner ring portion and the first outer ring tooth portion, causing the first inner ring portion to shift towards the direction of the second chainring relative to the first outer ring tooth portion; wherein the second inner ring portion and the second outer ring tooth portion of the second chainring are generally parallel; the second connecting portion is inclined relative to the second inner ring portion and the second outer ring tooth portion, causing the second inner ring portion to shift towards the direction of the first chainring relative to the second outer ring tooth portion. An improvement to the bicycle chainring structure as described in claim 1, wherein the first connecting portion and the second connecting portion are separated by an angle not equal to 0. The improved bicycle chainring structure as described in claim 2 further includes a third chainring with an outer diameter smaller than that of the second chainring, disposed on one side of the second chainring opposite to the first chainring; the third chainring has a third inner ring portion, a third connecting portion, and a third outer ring tooth portion; the third inner ring portion is radially inward of the third outer ring tooth portion; the third connecting portion is disposed between the third inner ring portion and the third outer ring tooth portion, with its two ends respectively connected to the third inner ring portion and the third outer ring tooth portion. The third inner ring portion of the third gear disk is generally parallel to the third outer ring portion; the third connecting portion is inclined relative to the third inner ring portion and the third outer ring portion, causing the third inner ring portion to shift relative to the third outer ring portion towards the second gear disk; the third inner ring portion of the third gear disk is attached to the second inner ring portion of the second gear disk, and the third outer ring portion of the third gear disk and the second outer ring portion of the second gear disk are axially spaced by a second predetermined distance. The improved bicycle chainring structure as described in claim 6, wherein the second connection and the third connection are separated by an angle not equal to 0. The improved bicycle chainring structure as described in claim 6 further includes a maximum chainring with an outer diameter larger than the first chainring, disposed on the side of the first chainring opposite the second chainring; the maximum chainring has a maximum inner ring portion, a maximum connecting portion, and a maximum outer ring tooth portion; the maximum inner ring portion is radially inward of the maximum outer ring tooth portion; the maximum connecting portion is disposed on the maximum... Between the inner ring portion and the largest outer ring tooth portion, both ends are respectively connected to the largest inner ring portion and the largest outer ring tooth portion; wherein the largest inner ring portion and the largest outer ring tooth portion of the largest tooth disk are generally parallel; the largest connecting portions are inclined relative to the largest inner ring portion and the largest outer ring tooth portion, so that the largest inner ring portion is offset relative to the largest outer ring tooth portion in a direction closer to the first tooth disk. The improved bicycle chainring structure as described in claim 8, wherein the largest inner ring of the largest chainring is fitted to the first outer ring of the first chainring, and the largest outer ring of the largest chainring and the first outer ring of the first chainring are axially spaced by a third predetermined distance. The bicycle chainring structure improvement as described in claim 8, wherein the largest connecting portion of the largest chainring and the first outer ring tooth portion of the first chainring are separated by an angle not equal to 0.