TW201936443A - Bicycle sprocket assembly - Google Patents

Abstract

A bicycle sprocket assembly having a rotational center axis is provided. The bicycle sprocket assembly comprises a first sprocket and a second sprocket. The first sprocket includes first teeth, a first sprocket body and a first engagement portion. The first sprocket body includes a central portion, a radially outer portion and an intermediate portion disposed between the central portion and the radially outer portion in a radial direction with respect to the rotational center axis of the bicycle sprocket assembly. The first teeth are formed along a radially outer periphery of the radially outer portion. The central portion has a torque transmitting profile engaged with at least one of a crank arm and a crank axle to transmit a pedaling torque from the crank arm to the first teeth. The first engagement portion is disposed on the first sprocket body. The second sprocket includes second teeth, a second sprocket body and a second engagement portion. The second sprocket body is formed with the second teeth along a radially outer periphery of the second sprocket body. The second engagement portion is disposed on the second sprocket body and engaged with the first engagement portion to position the second sprocket with respect to the first sprocket in at least one of a circumferential direction and the radial direction of the bicycle sprocket assembly with respect to the rotational center axis in an assembled state where the second sprocket is attached to the first sprocket.

Description

Bicycle sprocket assembly

The present invention relates to a bicycle sprocket assembly.

Cycling is becoming a popular form of entertainment and a means of transportation. One type of bicycle sprocket assembly is a direct mounted bicycle sprocket assembly. The direct mount bicycle sprocket assembly includes a sprocket, wherein one of the sprocket includes a central portion, a radially outer portion, and is disposed in a radial direction relative to one of the central axes of rotation of the bicycle sprocket assembly An intermediate portion between the central portion and the radially outer portion. The direct mount bicycle sprocket assembly is characterized in that the central portion has a bolt slot that engages at least one of a crank arm and a crank shaft to transmit a pedaling torque. A direct mount bicycle sprocket assembly typically employs screws to secure the sprocket wheels together and transmit pedaling torque between the sprocket wheels. However, the screws that secure the sprocket will become slack by long-term reciprocating pedaling torque.

According to a first aspect of the present invention, a bicycle sprocket assembly having a central axis of rotation includes a first sprocket and a second sprocket. The first sprocket includes a first tooth, a first sprocket body and a first engaging portion. The first sprocket body includes a central portion, a radially outer portion, and is disposed between the central portion and the radially outer portion in a radial direction relative to one of the central axes of rotation of the bicycle sprocket assembly A middle part of it. The first teeth are formed along a radially outer periphery of one of the radially outer portions. The center portion has engagement with at least one of a crank arm and a crank shaft to transmit a pedaling torque from the crank arm to a torque transmitting profile of the first teeth. The first engaging portion is disposed on the first sprocket body. The second sprocket includes a second tooth, a second sprocket body and a second meshing portion. The second sprocket body is formed with the second teeth along a radially outer periphery of one of the second sprocket bodies. The second engaging portion is disposed on the second sprocket body and engages the first engaging portion in an assembled state in which the second sprocket is attached to the first sprocket to engage the bicycle sprocket The assembly positions the second sprocket relative to the first sprocket with respect to at least one of a circumferential direction and a radial direction of the central axis of rotation.

With the bicycle sprocket assembly according to the first aspect, the fastening of the second sprocket to one of the first sprocket can be prevented from being loosened because the fastener is not used for the central axis relative to the rotation The first sprocket and the second sprocket are relatively positioned on at least one of a circumferential direction and the radial direction.

According to a second aspect of the present invention, the bicycle sprocket assembly according to the first aspect is configured such that the first engaging portion is formed on the intermediate portion.

With the bicycle sprocket assembly according to the second aspect, the intermediate portion facing the second sprocket in an axial direction with respect to the central axis of rotation can be used for a first engaging portion.

According to a third aspect of the present invention, the bicycle sprocket assembly according to the first aspect or the second aspect is configured such that the first engaging portion includes one of the first radial walls extending in the radial direction And the second engaging portion includes a second radial wall extending in the radial direction, and the first and second radial walls face each other in the circumferential direction in the assembled state.

With the bicycle sprocket assembly according to the third aspect, the first sprocket and the second sprocket can be positioned in the circumferential direction.

According to a fourth aspect of the present invention, the bicycle sprocket assembly according to the third aspect is configured such that the first radial wall is formed on one of the circumferential edges of the intermediate portion in the circumferential direction.

With the bicycle sprocket assembly according to the fourth aspect, it is not necessary to process an intermediate portion to form a first engaging portion.

According to a fifth aspect of the present invention, a bicycle sprocket assembly according to a fourth aspect is configured such that the second engaging portion includes a recess in which the second radial wall is formed, and the recess receives the intermediate portion Part of it.

With the bicycle sprocket assembly according to the fifth aspect, the first sprocket and the second sprocket can be positioned opposite each other clockwise and counterclockwise in the circumferential direction.

According to a sixth aspect of the present invention, the bicycle sprocket assembly according to any one of the first aspect to the fourth aspect is configured such that the first engaging portion includes one of the first extending in the circumferential direction The circumferential wall and the second engaging portion include a second circumferential wall extending in the circumferential direction, and the first and second circumferential walls face each other in the radial direction in the assembled state.

According to a seventh aspect of the present invention, a bicycle sprocket assembly according to a sixth aspect is configured such that the first engaging portion includes a first circumferential rib extending in the circumferential direction and the first circumference A wall is formed on the rib.

According to an eighth aspect of the present invention, the bicycle sprocket assembly according to the seventh aspect is configured such that the second sprocket body includes a cut portion, and the second circumferential wall is disposed on the cut portion. And the cutting portion receives the first circumferential rib in the assembled state.

With the bicycle sprocket assembly according to any one of the sixth aspect to the eighth aspect, the first sprocket and the second sprocket can be positioned in the radial direction.

According to a ninth aspect of the present invention, a bicycle sprocket assembly according to an eighth aspect is configured such that the intermediate portion includes a first attachment hole, and the second sprocket is fixed to the first sprocket A fastener passes through the aperture and the first circumferential rib is disposed radially away from the first attachment aperture.

According to a tenth aspect of the present invention, a bicycle sprocket assembly according to a ninth aspect is configured such that the second sprocket body includes a second attachment hole through which the fastener passes and the cutting The portion is disposed radially away from the second attachment aperture.

With the bicycle sprocket assembly according to the ninth aspect or the tenth aspect, the first connection to the second teeth and the transmission of a torque between the second sprocket body and the second teeth can be prevented The strength of the portion of the second sprocket body is reduced because the portion of the second sprocket body coupled to the second teeth will be disposed at the intercept portion away from the radially outer portion of the second attachment hole Weak down.

According to an eleventh aspect of the present invention, the bicycle sprocket assembly according to the sixth aspect is configured such that the second engaging portion includes a second circumferential rib formed on the rib .

According to a twelfth aspect of the present invention, the bicycle sprocket assembly according to the eleventh aspect is configured such that the first engaging portion includes a recessed portion, and the first circumferential wall is formed on the recessed portion And the recessed portion receives the second circumferential rib in the assembled state.

With the bicycle sprocket assembly according to the eleventh or twelfth aspect, the first sprocket and the second sprocket can be positioned in the radial direction.

According to a thirteenth aspect of the present invention, the bicycle sprocket assembly according to the twelfth aspect is configured such that the recessed portion is disposed between the intermediate portion and the radially outer portion in the radial direction. And the first sprocket body includes a bridge portion disposed adjacent to the recessed portion in the circumferential direction.

With the bicycle sprocket assembly according to the thirteenth aspect, the first engaging portion around the recessed portion can be reinforced.

According to an eleventh aspect of the present invention, the bicycle sprocket assembly according to the twelfth aspect or the thirteenth aspect is configured such that the intermediate portion includes a first attachment hole, the second sprocket A fastener secured to the first sprocket passes through the aperture and the recessed portion is disposed radially outward of the first attachment aperture.

According to a fifteenth aspect of the present invention, the bicycle sprocket assembly according to the fourteenth aspect is configured such that the second sprocket body includes a second attachment hole through which the fastener passes. The second circumferential rib is disposed radially outward of the second attachment aperture.

With the bicycle sprocket assembly according to the fourteenth or fifteenth aspect, the first sprocket and the second sprocket can be positioned in the radial direction.

According to a sixteenth aspect of the present invention, the bicycle sprocket assembly according to the sixth aspect is configured such that the first engaging portion includes a projection from the intermediate portion, and the projection defines the first circumference a wall and the first radial wall.

According to a seventeenth aspect of the present invention, the bicycle sprocket assembly according to the sixteenth aspect is configured such that the second engaging portion includes a recess in which the second circumferential wall is formed, and the recess receives the protrusion At least part of the ministry.

According to an eighteenth aspect of the present invention, a bicycle sprocket assembly according to the seventeenth aspect is configured such that the intermediate portion includes a first attachment hole, and the second sprocket is fixed to the first chain A fastener of the wheel passes through the aperture and the first circumferential wall on the projection is disposed radially outward of the first attachment aperture.

According to a nineteenth aspect of the present invention, the bicycle sprocket assembly according to the eighteenth aspect is configured such that the second sprocket body includes a second attachment hole through which the fastener passes. The second circumferential wall of the recess is disposed radially outward of the second attachment aperture.

With the bicycle sprocket assembly according to any one of the sixteenth aspect to the nineteenth aspect, the first circumferential wall and the first radial wall can be formed by a single protrusion, and thus the a circumferential wall and the first radial wall.

According to a twentieth aspect of the present invention, according to any one of the first aspect to the eighth aspect, the eleventh aspect to the thirteenth aspect, and the sixteenth aspect to the seventeenth aspect The bicycle sprocket assembly is configured such that the intermediate portion defines a first attachment surface, a first attachment aperture formed on the first attachment surface, the second sprocket body defining a second attachment surface, A second attachment aperture is formed on the second attachment surface and the fastener passes the first attachment aperture and the second attachment aperture to attach the second sprocket to the first sprocket.

With the bicycle sprocket assembly according to the twentieth aspect, the second sprocket can be tightly fixed to the first sprocket.

According to a twenty first aspect of the present invention, a bicycle sprocket assembly according to a twentieth aspect is configured such that the first attachment surface is configured to be parallel to the central axis of rotation in the assembled state One of the second attachment surfaces is in direct contact with one of the axial directions.

With the bicycle sprocket assembly according to the twenty-first aspect, the second sprocket can be positioned relative to the first sprocket in the axial direction.

According to a twenty-second aspect of the present invention, the bicycle sprocket assembly according to the twenty-first aspect is configured such that one of the first attachment hole and the second attachment hole is a through hole and the The other of the first attachment hole and the second attachment hole is a threaded hole through which the fastener is screwed to fix the second sprocket to the first sprocket, And in the assembled state, a gap is formed between the fastener and the through hole at least in a circumferential direction.

According to a twenty-third aspect of the present invention, the bicycle sprocket assembly according to any one of the first to twenty-second aspects is configured such that the total number of the first teeth is greater than the second teeth total.

According to a twenty-fourth aspect of the present invention, the bicycle sprocket assembly according to any one of the first to twenty-third aspects is configured such that the central portion includes at least the crank arm and the crank shaft One of the plurality of bolt slots engaged.

With the bicycle sprocket assembly according to any one of the twenty-second aspect to the twenty-fourth aspect, the fastener loosening of the second sprocket to the first sprocket can be prevented because the tight The firmware is not used to relatively position the first sprocket and the second sprocket in at least one of the circumferential direction and the radial direction relative to the central axis of rotation.

Selected embodiments of the present invention will now be explained with reference to the drawings. The present invention will be understood by those skilled in the art that the following description of the present invention is intended to be illustrative only and not to limit the invention as defined by the appended claims. First embodiment

Referring first to Figures 1A and 1B, a bicycle sprocket assembly 10 is a direct mount bicycle sprocket assembly. The bicycle sprocket assembly 10 having a center axis of rotation CA includes a first sprocket 12 and a second sprocket 14. The first sprocket 12 includes a first tooth 16, a first sprocket body 18 and at least one first engagement portion 20. The first sprocket body 18 includes a central portion 22, a radially outer portion 24, and a central portion 22 and a radially outer portion 24 disposed in a radial direction relative to a central axis of rotation CA of the bicycle sprocket assembly 10. At least one intermediate portion 26 between. The first tooth 16 is formed along a radially outer periphery of one of the radially outer portions 24. The central portion 22 has engagement with at least one of a crank arm CR and a crank axle (not shown) for transmitting a pedaling torque from the crank arm CR to one of the torque transmitting profiles 28 of the first tooth 16. In this embodiment, the torque transmitting profile 28 of the central portion 22 engages the crank arm CR. The first engaging portion 20 is disposed on the first sprocket body 18. The second sprocket 14 includes a second tooth 30, a second sprocket body 32, and at least a second engagement portion 34. The second sprocket body 32 is formed with a second tooth 30 having a radially outer periphery along one of the second sprocket bodies 32. The second engaging portion 34 is disposed on the second sprocket body 32 and engages with the first engaging portion 20 in an assembled state in which the second sprocket 14 is attached to the first sprocket 12 (FIG. 1A) to The bicycle sprocket assembly 10 positions the second sprocket 14 relative to the first sprocket 12 with respect to at least one of a circumferential direction of the central axis of rotation CA and the radial direction. In addition, a lock ring LR is used to mesh with the crank arm CR to clamp the bicycle sprocket assembly 10 between the lock ring LR and the crank arm CR in an axial direction parallel to the central axis of rotation CA. By the engagement between the second engaging portion 34 and the first engaging portion 20, a fastener 52 such as a screw is used to fix the second sprocket 14 to the first sprocket 12 only in the axial direction without using The first sprocket 12 and the second sprocket 14 are relatively positioned on at least one of a circumferential direction and a radial direction with respect to the central axis of rotation CA. Therefore, the fastener 52 will not carry the reciprocating pedaling torque and thus will not become loose due to the reciprocating pedaling torque after long-term use.

In this embodiment, for example, there are four intermediate portions 26, four of the first sprocket wheels 12, and four of the second sprocket wheels 14, but the number is not Limited to this. In the following description of the details of the bicycle sprocket assembly 10, only one of the intermediate portion 26, one of the first engaging portions 20, and one of the second engaging portions 34 will be described for the sake of brevity, due to other intermediate The portion, the first engaging portion and the second engaging portion have a substantially identical configuration.

The first engaging portion 20 is formed on the intermediate portion 26. As shown in FIGS. 1C and 1D, the first engaging portion 20 includes at least one first radial wall 36 extending in a radial direction and the second engaging portion 34 includes at least a second diameter extending in a radial direction. To the wall 38. As shown in FIGS. 1E and 1F, the first radial wall 36 and the second radial wall 38 face each other in the circumferential direction in the assembled state to transmit the pedaling torque in the circumferential direction. The first radial wall 36 is formed on one circumferential edge of the intermediate portion 26 in the circumferential direction. The second engagement portion 34 includes a recess 40 in which one of the second radial walls 38 is formed. The recess 40 receives a portion of the intermediate portion 26. Preferably, the inner edge of the recess 40 is formed with a slope SP as shown in Figure ID for preventing sharp edges. In a particular embodiment, the recess 40 can be 0.8 ± 0.1 mm deep and the second sprocket body 32 of the second sprocket 14 has a thickness of less than 5.1 mm.

As shown in FIG. 1C, the first engaging portion 20 includes one of the first circumferential walls 42 extending in the circumferential direction. As shown in FIG. 1D, the second engaging portion 34 includes a second circumferential wall 44 extending in the circumferential direction. As shown in FIGS. 1E and 1G, the first circumferential wall 42 and the second circumferential wall 44 face each other in the radial direction in the assembled state.

In this embodiment, the first engaging portions 20 each include a first circumferential rib 46 extending in the circumferential direction, and the first circumferential wall 42 is formed on the rib as shown in FIGS. 1C and 1G. The second sprocket body 32 includes a cut-away portion 48 that is disposed on the cut-away portion 48, as shown in Figure ID. The cutout 48 receives the first circumferential rib 46 in the assembled state, as shown in Figure 1G. Preferably, there is a gap CL between the cut portion 48 and the first circumferential rib 46. In a particular embodiment, the first circumferential rib 46 can protrude from the intermediate portion 26 by 0.8 ± 0.1 mm and the cut 48 is 1.1 ± 0.1 deep.

Please refer to Figure 1B. The intermediate portion 26 includes at least one first attachment aperture 50 through which the at least one fastener 52 securing the second sprocket 14 to the first sprocket 12 passes. In this embodiment, the first circumferential rib 46 is disposed radially away from the first attachment aperture 50, as shown in Figure 1C. The second sprocket body 32 includes at least one second attachment aperture 54 through which the fastener 52 passes and the cutout 48 is disposed radially away from the second attachment aperture 54, as shown in Figure ID.

Please refer to FIG. 1B to FIG. 1D. The intermediate portion 26 defines a first attachment surface 56 upon which the first attachment aperture 50 is formed. The second sprocket body 32 defines a second attachment surface 58 on which the second attachment aperture 54 is formed. The fastener 52 passes through the first attachment aperture 50 and the second attachment aperture 54 to attach the second sprocket 14 to the first sprocket 12. The first attachment surface 56 is configured to directly contact the second attachment surface 58 in an axial direction parallel to the central axis of rotation CA in the assembled state.

One of the first attachment hole 50 and the second attachment hole 54 is a through hole and the other of the first attachment hole 50 and the second attachment hole 54 is a threaded hole. The fastener 52 is screwed into the threaded hole via the through hole to fix the second sprocket 14 to the first sprocket 12, and one of the gaps GP as shown in FIGS. 1F and 1G is at least in the circumferential direction in the assembled state. Formed between the fastener 52 and the through hole. In this embodiment, the first attachment hole 50 is a threaded hole and the second attachment hole 54 is a through hole. The fastener 52 is screwed into the first attachment hole 50 via the second attachment hole 54 to fix the second sprocket 14 to the first sprocket 12 . The gap GP as shown in FIGS. 1F and 1G is formed between the fastener 52 and the second attachment hole 54 in both the circumferential direction and the radial direction in the assembled state to prevent use in the circumferential direction and the diameter. The fastener 52 that secures the second sprocket 14 to the first sprocket 12 in both directions is relaxed.

Please refer to FIG. 1A and FIG. 1B again. Typically and preferably, the total number of first teeth 16 is greater than the total number of second teeth 30. That is, the first sprocket 12 having the central portion 22 of the torque transmitting profile 28 that engages at least one of a crank arm CR and a crank axle (not shown) is a larger sprocket and the second sprocket 14 is A smaller sprocket. Preferably, the central portion 22 includes a plurality of pin slots for use as a torque transmitting profile 28 that engages at least one of a crank arm CR and a crank axle (not shown). More specifically, in the illustrated embodiment, the crank arm CR includes a mounting tab CRM formed through one of the mounting holes CRH about the crankshaft. The mounting protrusion CRM protrudes from one end of the crank arm CR in the axial direction. The mounting tab includes a plurality of pin slots CRS that surround the periphery of the mounting tab CRM to engage the plurality of pin slots CRS of the torque transmitting profile 28.

Please refer to Figure 1A. The first sprocket 12 further includes a first sprocket body 18 for assisting in shifting one of the chain CHs from the smaller second sprocket 14 to the larger first sprocket 12 as shown in FIGS. 1I and 1J. A plurality of shift assist projections 60 are operated. A shift zone SA is defined on each of the first sprocket 12 adjacent to the shift assisting projection 60. For details of one of the shift zones SA, please refer to FIG. 1H. The shifting area SA shown in FIG. 1H includes a plurality of shifting teeth of the first tooth 16 (eg, four shifting teeth in this example), which may be in the chain CH from the smaller second sprocket 14 to The chain CH is contacted during the shifting operation of the large first sprocket 12. The first tooth 16 includes a first chain receiving tooth 62 and a second chain receiving tooth 64 that are adjacent to an end of the shifting area SA in an upstream direction UD with respect to a chain running direction. The first chain receiving tooth 62 and the second chain receiving tooth 64 engage the first and second teeth of the chain CH during a shifting operation. The first chain receiving tooth 62 and the second chain receiving tooth 64 are respectively formed with a cutout 66 on the tip end portion thereof for easy engagement with the chain CH. Specifically, the cut portion 66 is formed on one edge of the tip end portion of the first chain receiving tooth 62 and the second chain receiving tooth 64 in the downstream direction DD with respect to the chain running direction. Due to the cut portion 66, one of the first chain receiving teeth 62 and the second chain receiving tooth 64 has a tooth tip 68 in the upstream direction UD of the chain running direction with respect to the first chain receiving tooth 62 and the second chain. One of the receiving teeth 64 is offset by a circumferential centerline CC.

Please refer to FIG. 1I and FIG. 1J. During a shifting operation from the smaller second sprocket 14 to the larger first sprocket 12, the chain CH first engages the shift assisting projection 60, as shown in FIG. As shown in FIG. 1J, the first chain receiving teeth 62 are easily engaged with the chain CH. By means of the first chain receiving tooth 62 and the second chain receiving tooth 64, the first chain receiving tooth 62 and the second chain receiving tooth 64 can easily engage the chain CH outside the chain plate OP through the inlet EH of the meshing area. The meshing area between the two. In the chain CH of this example, the inlet EH of the meshing region between the outer link plates OP is formed to be smaller than usual because the inner link plate IP of the chain CH is formed to be wider than usual to more securely hold the teeth of the sprocket. . However, the smaller inlet EH makes the engagement of the chain CH to the teeth of the sprocket more difficult. The cutout 66 ensures that the first chain receiving tooth 62 and the second chain receiving tooth 64 smoothly engage the chain CH during the shifting operation. Therefore, the chain receiving teeth 62, 64 and the chain CH outside the chain plate OP can be shifted when the chain CH is shifted from a smaller sprocket (second sprocket 14) toward a larger sprocket (first sprocket 12). Determined and smoothly engaged.

Please refer to FIG. 1K and FIG. 1L. The crank arm CR of this embodiment is a hollow crank arm and includes an inner portion CRI and an outer casing CRO. The inner portion CRI and an outer casing CRO are assembled and joined together to form a crank arm CR. Preferably, the inner portion CRI is formed to have a vent hole VH. The bonding between the inner portion CRI and the outer casing CRO is achieved using an adhesive. Although the adhesive is cured at a high temperature, gas is allowed to escape from the inside of the hollow crank arm CR through the vent hole VH. Because some further procedures, such as an anodizing procedure, can be applied to the assembled crank arm CR, the vent VH should be sealed by a seal to prevent any undesirable material from entering the crank arm CR. Therefore, the crank arm CR of this embodiment further includes a sealing bolt SB to seal the vent hole VH. The vent hole VH has a thread such that the seal bolt SB is screwed into the vent hole VH and seals the vent hole VH.

For details of the sealing bolt SB, please refer to Figure 1M. Preferably, the sealing bolt SB includes a flange SBF, a threaded portion SBT and a recess SBO. The flange SBF is used to cover and seal the vent hole VH. The threaded portion SBT is used for screwing into the vent hole VH. An O-ring can be placed in the recess SBO to seal the vent VH.

In an alternative embodiment, the second radial wall 38 can be formed only in one side of each of the attachment holes 54 in the circumferential direction. In other words, as shown in FIG. 1N, the second radial wall 38 is not formed at the other side of each of the attachment holes 54 on the second sprocket 14, and thus the corresponding first radial wall 36 does not contact any Second radial wall 38. In this alternative embodiment, as shown in Figure 1 N, there are four second radial walls 38. There is a pair of adjacent attachment holes 54 between a pair of adjacent second radial walls 38 in the circumferential direction. There is no second radial wall 38 between the other pair of adjacent attachment holes 54 in the circumferential direction. The first sprocket 12 and the second sprocket 14 can be positioned in the circumferential direction by the two adjacent second radial walls 38.

Although the above alternative embodiment relates to the second radial wall, it is also possible to form the first radial wall or the first and second radial walls on only one side of the attachment hole in the circumferential direction.

In another alternative embodiment, a second radial wall 38 can be formed that is only adjacent to both of the attachment holes. As shown in FIG. 10, each of the first pair of attachment holes 54 is circumferentially disposed between a pair of adjacent second radial walls 38 to position the first sprocket 12 and the second chain in the circumferential direction. Wheel 14. A second radial wall 38 adjacent to a second pair of attachment holes 54' is not formed. In other words, in one aspect, the second radial wall 38 is formed in the circumferential direction near both sides of the first pair of attachment holes 54. On the other hand, the second radial wall is not formed in the circumferential direction near either side of the second pair of attachment holes 54'. The first pair of attachment holes 54 are disposed to face each other with respect to the central axis of rotation CA. The other two attachment holes 54' (i.e., the second pair of attachment holes 54') are also disposed opposite each other with respect to the central axis of rotation CA. The attachment holes 54 and 54' are alternately arranged adjacent to each other in the circumferential direction. The diameter of the second pair of attachment holes 54' (through holes) is larger than the diameter of the first pair of attachment holes 54 (through holes) to prevent the fastener 52 from abutting the attachment holes 54'. Therefore, the positioning of the first sprocket 12 and the second sprocket 14 in the circumferential direction can be ensured by the first radial wall 36 and the second radial wall 38 instead of by the fastener 52.

While the above alternative embodiments relate to the second radial wall, it is also possible to form a first radial wall or first and second radial walls that are only adjacent to both of the attachment holes in the circumferential direction. Second embodiment

For a second embodiment of a bicycle sprocket assembly 210, please refer to Figures 2A and 2B. Similar to the first embodiment, the bicycle sprocket assembly 210 includes a first sprocket 212 and a second sprocket 214. The first sprocket 212 includes a first tooth 216, a first sprocket body 218, and at least a first engagement portion 220. The first sprocket body 218 includes a central portion 222, a radially outer portion 224, and a central portion 222 and a radially outer portion 224 disposed in a radial direction relative to a central axis of rotation CA of the bicycle sprocket assembly 210. At least one intermediate portion 226 between. The first tooth 216 is formed along a radially outer periphery of one of the radially outer portions 224. The central portion 222 has a torque transmission profile 228 that engages at least one of a crank arm CR and a crankshaft (not shown) as shown in FIG. 1B to transmit a pedaling torque from the crank arm CR to the first tooth 216. In this embodiment, the torque transmitting profile 228 of the central portion 222 is for engagement with the crank arm CR, as shown in Figure IB. The first engaging portion 220 is disposed on the first sprocket body 218. The second sprocket 214 includes a second tooth 230, a second sprocket body 232 and at least one second engaging portion 234. The second sprocket body 232 is formed with a second tooth 230 having a radially outer periphery along one of the second sprocket bodies 232. The second engaging portion 234 is disposed on the second sprocket body 232 and engages with the first engaging portion 220 in an assembled state in which the second sprocket 214 is attached to the first sprocket 212 (FIG. 2A) to The bicycle sprocket assembly 210 positions the second sprocket 214 relative to the first sprocket 212 with respect to at least one of a circumferential direction of the central axis of rotation CA and the radial direction.

The first engaging portion 220 is formed on the intermediate portion 226. As shown in Figures 2C and 2D, the first engagement portion 220 includes at least one first radial wall 236 extending in a radial direction and the second engagement portion 234 includes at least a second diameter extending in a radial direction. To the wall 238. As shown in FIGS. 2E and 2F, the first radial wall 236 and the second radial wall 238 face each other in the circumferential direction in the assembled state to transmit the pedaling torque in the circumferential direction. In this embodiment, the first radial wall 236 is formed on one of the circumferential edges of the intermediate portion 226 in the circumferential direction. The second engagement portion 234 includes a recess 240 in which one of the second radial walls 238 is formed, and the recess 240 receives a portion of the intermediate portion 226. Preferably, the inner edge of the recess 240 is formed as a rounded edge RE as shown in Figure 2D for preventing sharp edges. In one particular embodiment, the recess 240 can be 0.8 ± 0.1 mm deep and the second sprocket body 232 of the second sprocket 214 has a thickness of less than 5.1 mm.

As shown in FIG. 2C, the first engaging portion 220 includes one of the first circumferential walls 242 extending in the circumferential direction. As shown in FIG. 2D, the second engaging portion 234 includes a second circumferential wall 244 that extends in the circumferential direction. As shown in FIG. 2G, the first circumferential wall 242 and the second circumferential wall 244 face each other in the radial direction in the assembled state.

Other details and alternatives to the components of the bicycle sprocket assembly 210 are similar to those of the bicycle sprocket assembly 10 of the first embodiment and are therefore not described below. Portions of the bicycle sprocket assembly 210 that are different from the portion of the bicycle sprocket assembly 10 of the first embodiment are described below.

As shown in FIG. 2D, the second engagement portion 234 of the second embodiment includes a second circumferential rib 246 on which one of the second circumferential walls 244 is formed. Accordingly, the first engagement portion 220 includes a recessed portion 248, and a first circumferential wall 242 is formed on the recessed portion 248, as shown in Figure 2C. The recessed portion 248 receives the second circumferential rib 246 in the assembled state, as shown in Figure 2G. Preferably, the outer edge of the first circumferential wall 242 is formed to have a chamfer CF, as shown in Figure 2G. In a particular embodiment, the second circumferential rib 246 can have a thickness of 0.8 ± 0.1 mm.

Please refer to Figure 2C. Preferably, the recessed portion 248 is disposed between the intermediate portion 226 and the radially outer portion 224 in the radial direction. The first sprocket body 218 includes at least one bridging portion 249 disposed adjacent to the recessed portion 248 in a circumferential direction. The bridge portion 249 smoothly connects the first circumferential wall 242 to the radially outer portion 224. Please refer to FIG. 2B to FIG. 2F. The intermediate portion 226 includes a first attachment aperture 250 through which the second sprocket 214 is secured to one of the first sprocket 212 fasteners 252. In this embodiment, the recessed portion 248 is disposed radially outward of the first attachment aperture 250. Thus, the second sprocket body 232 includes a second attachment aperture 254 through which the fastener 252 passes. The second circumferential rib 246 for engaging the recessed portion 248 is disposed radially outward of the second attachment aperture 254. Third embodiment

For a third embodiment of a bicycle sprocket assembly 310, please refer to Figures 3A and 3B. Similar to the first embodiment, the bicycle sprocket assembly 310 includes a first sprocket 312 and a second sprocket 314. The first sprocket 312 includes a first tooth 316, a first sprocket body 318, and at least a first engagement portion 320. The first sprocket body 318 includes a central portion 322, a radially outer portion 324, and a central portion 322 and a radially outer portion 324 disposed in a radial direction relative to a central axis of rotation CA of the bicycle sprocket assembly 310. At least one intermediate portion 326 between. The first tooth 316 is formed along a radially outer periphery of one of the radially outer portions 324. The central portion 322 has a torque transmission profile 328 that engages at least one of a crank arm CR and a crankshaft (not shown) as shown in FIG. 1B to transmit a pedaling torque from the crank arm CR to the first tooth 316. In this embodiment, the torque transmitting profile 328 of the central portion 322 is for engagement with the crank arm CR. The first engaging portion 320 is disposed on the first sprocket body 318. The second sprocket 314 includes a second tooth 330, a second sprocket body 332 and at least one second engaging portion 334. The second sprocket body 332 is formed with a second tooth 330 having a radially outer periphery along one of the second sprocket bodies 332. The second engaging portion 334 is disposed on the second sprocket body 332 and engages with the first engaging portion 320 in an assembled state in which the second sprocket 314 is attached to the first sprocket 312 (FIG. 3A) to The bicycle sprocket assembly 310 positions the second sprocket 314 relative to the first sprocket 312 with respect to at least one of a circumferential direction of the central axis of rotation CA and the radial direction.

The first engaging portion 320 is formed on the intermediate portion 326. As shown in Figures 3C and 3D, the first engagement portion 320 includes at least one first radial wall 336 extending in a radial direction and the second engagement portion 334 includes at least a second diameter extending in a radial direction. To the wall 338. As shown in FIGS. 3E and 3F, the first radial wall 336 and the second radial wall 338 face each other in the circumferential direction in the assembled state to transmit the pedaling torque in the circumferential direction. A first radial wall 336 is formed on one of the circumferential edges of the intermediate portion 326 in the circumferential direction. The second engagement portion 334 includes a recess 340 in which one of the second radial walls 338 is formed, and the recess 340 receives a portion of the intermediate portion 326. Preferably, the inner edge of the recess 340 is formed as a rounded edge RE as shown in Figure 3D for preventing sharp edges. In one particular embodiment, the recess 340 can be 0.8 ± 0.1 mm deep and the second sprocket body 332 of the second sprocket 314 has a thickness of less than 5.1 mm.

As shown in FIG. 3C, the first engaging portion 320 includes one of the first circumferential walls 342 extending in the circumferential direction. As shown in FIG. 3D, the second engaging portion 334 includes a second circumferential wall 344 that extends in the circumferential direction. As shown in FIG. 3G, the first circumferential wall 342 and the second circumferential wall 344 face each other in the radial direction in the assembled state.

Other details and alternatives to the components of bicycle sprocket assembly 310 are similar to the details and alternatives of bicycle sprocket assembly 10 of the first embodiment and will therefore not be described below. Portions of the bicycle sprocket assembly 310 that are different from the portion of the bicycle sprocket assembly 10 of the first embodiment are described below.

As shown in FIG. 3C, the first engagement portion 320 of this embodiment includes a protrusion 346 that protrudes from the intermediate portion 326. The protrusion 346 defines a first circumferential wall 342 and a first radial wall 336. Therefore, in this embodiment, the second circumferential wall 344 is formed in the recess 340 included by the second engaging portion 334. The recess 340 receives at least a portion of the projection 346 in an assembled state, as shown in Figure 3G. Preferably, the outer edge of the first circumferential wall 342 on the projection 346 is formed to have a chamfer CF, as shown in Figure 3G.

Please refer to FIG. 3B to FIG. 3F. The intermediate portion 326 includes a first attachment aperture 350 that secures the second sprocket 314 to one of the first sprocket 312 fasteners 352 therethrough. In this embodiment, the first circumferential wall 342 on the projection 346 is disposed radially outward of the first attachment aperture 350. Accordingly, the second sprocket body 314 includes a fastener 352 passing through one of the second attachment holes 354, and the second circumferential wall 344 of the recess is disposed radially outward of the second attachment hole 354.

Those skilled in the bicycle art will appreciate from this disclosure that the above-described embodiments may be at least partially combined with each other as needed or desired.

In the present application, the term "comprise" and its derivatives are used herein to mean an open term that specifies the existence of the stated features, components, components, groups, integers and/or steps. The existence of other unreported features, components, components, groups, integers and/or steps is not excluded. This concept also applies to words with similar meanings, for example, the terms "having", "including" and their derivatives.

The terms "parts", "sections", "parts", "parts", "components", "body" and "structure" may have the dual meaning of a single part or a plurality of parts when used in the singular.

The ordinal numbers such as "first" and "second" as set forth in this application are merely identifiers and do not have any other meaning (for example, a particular order or the like). Moreover, for example, the term "first element" does not itself imply the existence of a "second element", and the term "second element" does not itself imply the existence of a "first element."

The term "pair" as used herein may also encompass a configuration in which the pair of elements have different shapes or configurations from each other, except that the pair of elements have the same shape or configuration.

The terms "a", "one or more" and "said" are used interchangeably herein.

Finally, degree terms (such as "substantially", "about" and "approximately" as used herein mean a reasonable amount of deviation of one of the modified terms so that the final result does not change significantly. All numerical values described in this application are considered to include terms such as "substantially", "about" and "approximate".

Obviously, many modifications and variations of the present invention are possible in light of the above teachings. Therefore, it is to be understood that the invention may be practiced otherwise than as specifically described herein.

10‧‧‧Bicycle sprocket assembly

12‧‧‧First sprocket

14‧‧‧Second sprocket

16‧‧‧First tooth

18‧‧‧First sprocket body

20‧‧‧Meshing part

22‧‧‧ central part

24‧‧‧ radially outer part

26‧‧‧ middle part

28‧‧‧ Torque transmission profile

30‧‧‧second tooth

32‧‧‧Second sprocket body

34‧‧‧Second engagement part

36‧‧‧First radial wall

38‧‧‧second radial wall

40‧‧‧ recess

42‧‧‧First circumferential wall

44‧‧‧Second circumferential wall

46‧‧‧First circumferential rib

48‧‧‧cutting department

50‧‧‧First attachment hole

52‧‧‧fasteners

54‧‧‧Second attachment hole

54'‧‧‧ Attachment hole

56‧‧‧First attachment surface

58‧‧‧Second attachment surface

60‧‧‧Shift auxiliary protrusion

62‧‧‧First chain receiving teeth

64‧‧‧Second chain receiving teeth

66‧‧‧cutting department

68‧‧‧ tooth top

210‧‧‧Bicycle sprocket assembly

212‧‧‧First sprocket

214‧‧‧Second sprocket

216‧‧‧first tooth

218‧‧‧First sprocket body

220‧‧‧First meshing part

222‧‧‧ central part

224‧‧‧ radially outer part

226‧‧‧ middle part

228‧‧‧Torque transmission profile

230‧‧‧second tooth

232‧‧‧Second sprocket body

234‧‧‧Second engagement part

236‧‧‧First radial wall

238‧‧‧second radial wall

240‧‧‧ recess

242‧‧‧First circumferential wall

244‧‧‧Second circumferential wall

246‧‧‧second circumferential rib

248‧‧‧ recessed part

249‧‧‧Bridge section

250‧‧‧First attachment hole

252‧‧‧fasteners

254‧‧‧Second attachment hole

310‧‧‧Bicycle sprocket assembly

312‧‧‧First sprocket

314‧‧‧Second sprocket

316‧‧‧first tooth

318‧‧‧First sprocket body

320‧‧‧First meshing part

322‧‧‧ central part

324‧‧‧ radially outer part

326‧‧‧ middle part

328‧‧‧Torque transmission profile

330‧‧‧second tooth

332‧‧‧Second sprocket body

334‧‧‧Second engagement part

336‧‧‧First radial wall

338‧‧‧second radial wall

340‧‧‧ recess

342‧‧‧First circumferential wall

344‧‧‧Second circumferential wall

346‧‧‧Protruding

350‧‧‧First attachment hole

352‧‧‧fasteners

354‧‧‧Second attachment hole

CA‧‧‧Rotation Center Shaft

CF‧‧‧Chamfer

CH‧‧‧Chain

CL‧‧‧ gap

CR‧‧‧ crank arm

CRH‧‧‧ mounting hole

Part of CRI‧‧

CRM‧‧‧Installation

CRO‧‧‧ outer casing

CRS‧‧‧Bolt

DD‧‧‧ downstream direction

EH‧‧‧ entrance

GP‧‧‧ gap

IP‧‧‧ inner chain board

LR‧‧‧Lock ring

OP‧‧‧ outer chain board

RE‧‧‧round edge

SA‧‧ ‧ shifting area

SB‧‧‧ sealing bolt

SBF‧‧‧Flange

SBO‧‧‧ recess

SBT‧‧‧ threaded part

SP‧‧‧ slope

UD‧‧‧ upstream direction

VH‧‧ ventilation

A more complete understanding of the present invention, together with one of its various advantages, will be more fully understood.

1A is a perspective view of a bicycle sprocket assembly in accordance with a first embodiment of the present invention.

Figure 1B is an exploded perspective view of a bicycle sprocket assembly in accordance with a first embodiment of the present invention.

Figure 1C is a partially enlarged view of a first sprocket according to a first embodiment of the present invention.

Figure 1D is a partially enlarged view of a second sprocket according to a first embodiment of the present invention.

Figure 1E is a partially enlarged view of a first sprocket and a second sprocket in an assembled state in accordance with a first embodiment of the present invention.

Figure 1F is a partial cross-sectional view of a bicycle sprocket assembly taken along line 1F-1F of Figure 1A.

Figure 1G is a partial cross-sectional view of a bicycle sprocket assembly taken along line 1G-1G of Figure 1A.

1H is a partial enlarged view of a bicycle sprocket assembly in accordance with a first embodiment of the present invention showing details of one of the shifting regions.

1I is a partial enlarged view showing a shift assisting projection of one of the bicycle sprocket assemblies according to the first embodiment of the present invention entering a chain during a shifting operation.

1J is a partial enlarged view showing an engagement between a chain of a bicycle sprocket assembly and a shift assisting projection according to a first embodiment of the present invention during a shifting operation.

1K shows a crank arm used in conjunction with a bicycle sprocket assembly in accordance with a first embodiment of the present invention, wherein a sealing bolt is inserted into a vent.

1L shows a crank arm for use with a bicycle sprocket assembly in accordance with a first embodiment of the present invention, wherein the sealing bolt is separated from the vent.

Figure 1M shows a side view of the sealing bolt shown in Figures 1K and 1L.

Figure 1N shows an alternative embodiment of the first embodiment of the invention wherein the second radial wall is formed in the circumferential direction only at one side of each of the attachment holes.

Figure 10 shows another alternative embodiment of the first embodiment of the invention wherein the second radial wall is adjacent only to both of the attachment holes.

2A is a perspective view of a bicycle sprocket assembly in accordance with a second embodiment of the present invention.

Figure 2B is an exploded perspective view of a bicycle sprocket assembly in accordance with a second embodiment of the present invention.

Figure 2C is a partially enlarged view of a first sprocket according to a second embodiment of the present invention.

Figure 2D is a partially enlarged view of a second sprocket according to a second embodiment of the present invention.

Figure 2E is a partial enlarged view of one of the first sprocket and the second sprocket in an assembled state in accordance with a second embodiment of the present invention.

Figure 2F is a partial cross-sectional view of a bicycle sprocket assembly taken along line 2F-2F of Figure 2A.

2G is a partial cross-sectional view of a bicycle sprocket assembly taken along line 2G-2G of FIG. 2A.

Figure 3A is a perspective view of a bicycle sprocket assembly in accordance with a third embodiment of the present invention.

Figure 3B is an exploded perspective view of a bicycle sprocket assembly in accordance with a third embodiment of the present invention.

Figure 3C is a partial enlarged view of a first sprocket according to a third embodiment of the present invention.

Figure 3D is a partially enlarged view of a second sprocket according to a third embodiment of the present invention.

Figure 3E is a partial enlarged view of one of the first sprocket and the second sprocket in an assembled state in accordance with a third embodiment of the present invention.

Figure 3F is a partial cross-sectional view of a bicycle sprocket assembly taken along line 3F-3F of Figure 3A.

Figure 3G is a partial cross-sectional view of a bicycle sprocket assembly taken along line 3G-3G of Figure 3A.

Claims (20)

A bicycle sprocket assembly having a rotating central shaft, the bicycle sprocket assembly comprising: a first sprocket including a first tooth, a first sprocket body including a central portion and a radially outer portion a portion and an intermediate portion disposed between the central portion and the radially outer portion in a radial direction relative to one of the central axes of rotation of the bicycle sprocket assembly, the first teeth along the radial direction a radially outer periphery of one of the outer portions, the central portion having at least one of a crank arm and a crank shaft for transmitting a pedaling torque from the crank arm to a torque transmitting profile of the first teeth, and a a first engaging portion disposed on the first sprocket body; and a second sprocket comprising: a second tooth, a second sprocket body having one of the second sprocket bodies The second teeth formed by the radially outer periphery, and a second engaging portion disposed on the second sprocket body and attached to the assembled state of the first sprocket at the second sprocket Engaging with the first engaging portion to the total of the bicycle sprocket With respect to the rotation center axis of one of the circumferential direction and the radial direction of the relative positioning of one of the at least the second sprocket to the first sprocket. A bicycle sprocket assembly according to claim 1, wherein the first engaging portion is formed on the intermediate portion. The bicycle sprocket assembly of claim 1 or 2, wherein the first engaging portion includes one of the first radial walls extending in the radial direction and the second engaging portion includes one of the extending in the radial direction a second radial wall, and the first and second walls face each other in the circumferential direction in the assembled state, preferably, the first radial wall is formed in the circumferential direction in one of the intermediate portions On the edge of the circumference. The bicycle sprocket assembly of claim 3, wherein the second engagement portion includes a recess in which the second radial wall is formed, and the recess receives a portion of the intermediate portion. The bicycle sprocket assembly of claim 1 or 2, wherein the first engaging portion includes one of the first circumferential walls extending in the circumferential direction and the second engaging portion includes one of the second circumferences extending in the circumferential direction a wall, and the first and second circumferential walls face each other in the radial direction in the assembled state. The bicycle sprocket assembly of claim 5, wherein the first engaging portion includes a first circumferential rib extending in the circumferential direction and the first circumferential wall is formed on the rib, preferably The second sprocket body includes a cutout portion, the second circumferential wall is disposed on the cutout portion, and the cutout portion receives the first circumferential rib portion in the assembled state. The bicycle sprocket assembly of claim 6, wherein the intermediate portion includes a first attachment hole, the second sprocket is fixed to the fastener of the first sprocket through the hole, and the first circumferential rib The portion is disposed radially away from the first attachment aperture. The bicycle sprocket assembly of claim 7, wherein the second sprocket body includes a second attachment hole through which the fastener passes, and the cut portion is disposed away from the second attachment hole To the inside. The bicycle sprocket assembly of claim 5, wherein the second engaging portion includes a second circumferential rib formed on the rib, preferably the first engaging portion includes a recess In part, the first circumferential wall is formed on the recessed portion, and the recessed portion receives the second circumferential rib in the assembled state. The bicycle sprocket assembly of claim 9, wherein the recessed portion is disposed between the intermediate portion and the radially outer portion in the radial direction, and the first sprocket body includes being disposed in the circumferential direction A bridge portion adjacent to one of the recessed portions. The bicycle sprocket assembly of claim 9, wherein the intermediate portion includes a first attachment hole, the second sprocket is fixed to the fastener of the first sprocket through the hole, and the recessed portion is Positioned radially away from the first attachment aperture. The bicycle sprocket assembly of claim 11, wherein the second sprocket body includes a second attachment hole through which the fastener passes and the second circumferential rib is disposed away from the second attachment hole Radial outside. The bicycle sprocket assembly of claim 5, wherein the first engagement portion includes a projection from the intermediate portion, and the projection defines the first circumferential wall and the first radial wall, preferably, the The second engagement portion includes a recess in which the second circumferential wall is formed, and the recess receives at least a portion of the projection. The bicycle sprocket assembly of claim 13, wherein the intermediate portion includes a first attachment hole, the second sprocket is fixed to the fastener of the first sprocket through the hole, and the protrusion is The first circumferential wall is disposed radially outward of the first attachment aperture. The bicycle sprocket assembly of claim 14, wherein the second sprocket body includes a second attachment hole through which the fastener passes, and the second circumferential wall of the recess is disposed away from the second Attach the radial outer side of the hole. The bicycle sprocket assembly of claim 1 or 2, wherein the intermediate portion defines a first attachment surface, a first attachment aperture formed on the first attachment surface, the second sprocket body defining a first a second attachment surface formed on the second attachment surface, and a fastener passing through the first attachment aperture and the second attachment aperture to attach the second sprocket to the The first sprocket. The bicycle sprocket assembly of claim 16, wherein the first attachment surface is configured to directly contact the second attachment surface in an axial direction parallel to one of the central axes of rotation in the assembled state. The bicycle sprocket assembly of claim 17, wherein one of the first attachment hole and the second attachment hole is a through hole and the other of the first attachment hole and the second attachment hole a threaded hole through which the fastener is screwed to fix the second sprocket to the first sprocket, and in the assembled state, at least in the circumferential direction of the fastener A gap is formed with the through hole. The bicycle sprocket assembly of claim 1 or 2, wherein the total number of the first teeth is greater than the total number of the second teeth. The bicycle sprocket assembly of claim 1 or 2, wherein the central portion includes a plurality of latching slots that engage the at least one of the crank arm and the crankshaft.