Bicycle hub arrangement

Abstract

Bicycle hub assembly (12) comprising: a sprocket support body (28) having at least ten external spline teeth (40) configured to engage a rear bicycle sprocket assembly (14), each of the at least ten external spline teeth (40) having an external spline drive surface (48) and an external spline non-drive surface (50), each of the at least ten external spline teeth (40) having the external spline drive surface (48) to receive a driving rotational force from the rear bicycle sprocket assembly (14) upon pedaling, the plurality of external spline drive surfaces (48) each comprising a radially outermost edge (48A), a radially innermost edge (48B), and a radial length (RL11) defined from the radially outermost edge (48A) to the radially innermost edge (48B), and a total sum of the radial lengths (RL11) of the external spline drive surfaces (48) is equal to or greater than 7 mm; and at least one external spline drive surface (48) of the at least ten external spline drive surfaces (48) having a first external spline surface angle (AG11) defined between the at least one external spline drive surface (48) and a first radial line (L11) extending from a rotational center axis (A1) of the bicycle hub assembly (12) to the radially outermost edge (48A) of the at least one external spline drive surface (48), the first external spline surface angle (AG11) being in the range of 0 degrees to 10 degrees.

Description

BACKGROUND OF THE INVENTION REFERENCE TO OTHER APPLICATIONS

[0001] This application claims priority to U.S. patent application US 15 / 608,924 and U.S. patent application US 15 / 608,915, filed May 30, 2017. The entire disclosure of U.S. patent application US 15 / 608,924 and U.S. patent application US 15 / 608,915 is hereby incorporated by reference. FIELD OF THE INVENTION

[0002] The present invention relates to a bicycle hub assembly. DISCUSSION OF THE BACKGROUND

[0003] Cycling is becoming an increasingly popular form of recreation as well as a means of transportation. Furthermore, cycling has become a very popular competitive sport for both amateurs and professionals. Whether the bicycle is used for recreation, transportation, or competition, the bicycle industry is constantly improving the various components of the bicycle. One bicycle component that has undergone extensive redesign is the hub assembly. Bicycle hub assemblies with a sprocket support body are known from DE 600 22 250 T2, US 2010 / 0 260 544 A1, US 2016 / 0 176 477 A1, US 2005 / 0 209 033 A1, US 4 869 710 A, DE 10 2015 005 141 A1, and US 2013 / 0 184 109 A1. SUMMARY OF THE INVENTION

[0004] According to a first aspect of the present invention, a bicycle hub assembly comprises a sprocket support body. The sprocket support body includes at least ten external spline teeth configured to engage a rear bicycle sprocket assembly. Each of the at least ten external spline teeth includes an external spline drive surface and an external spline non-drive surface. Each of the at least ten external spline teeth includes the external spline drive surface for receiving a driving rotational force from the rear bicycle sprocket assembly upon pedaling, wherein the plurality of external spline drive surfaces each includes a radially outermost edge, a radially innermost edge, and a radial length defined from the radially outermost edge to the radially innermost edge, and wherein a total sum of the radial lengths of the external spline drive surfaces is equal to or greater than 7 mm.At least one external spline drive surface of the at least ten external spline drive surfaces has a first external spline face angle defined between the at least one external spline drive surface and a first radial line extending from a rotational center axis of the bicycle hub assembly to the radially outermost edge of the at least one external spline drive surface, the first external spline face angle being in the range of 0 degrees to 10 degrees.

[0005] With the bicycle hub assembly according to the first aspect, the at least ten external spline teeth reduce a rotational force acting on each of the at least ten external spline teeth compared to a sprocket support body with nine or fewer external spline teeth. This improves the durability of the sprocket support body and / or improves the degree of freedom in selecting a material for the sprocket support body without reducing the durability of the sprocket support body.

[0006] According to a second aspect of the present invention, the bicycle hub assembly according to the first aspect is configured such that a total number of the at least ten external splines is equal to or greater than 20.

[0007] With the bicycle hub assembly according to the second aspect, the at least twenty external splines further reduce the rotational force acting on each of the at least twenty external splines compared to a sprocket support body with nine or fewer external splines. This further improves the durability of the sprocket support body and / or improves a degree of freedom in selecting a material for the sprocket support body without reducing the durability of the sprocket support body.

[0008] According to a third aspect of the present invention, the bicycle hub assembly according to the second aspect is configured such that the total number of the at least ten external splines is equal to or greater than 25.

[0009] With the bicycle hub assembly according to the third aspect, the at least twenty-five external splines further reduce the rotational force applied to each of the at least twenty-five external splines compared to a sprocket support body having nine or fewer external splines. This further improves the durability of the sprocket support body and / or improves a degree of freedom in selecting a material for the sprocket support body without reducing the durability of the sprocket support body.

[0010] According to a fourth aspect of the present invention, the bicycle hub assembly according to any one of the first to third aspects is configured such that the at least ten external splines have a first outer pitch angle and a second outer pitch angle different from the first outer pitch angle.

[0011] With the bicycle hub assembly according to the fourth aspect, the difference between the first outer pitch angle and the second outer pitch angle helps the user to correctly attach the rear bicycle sprocket assembly to the sprocket support body, particularly with respect to a circumferential position of each sprocket of the rear bicycle sprocket assembly.

[0012] According to a fifth aspect of the present invention, the bicycle hub assembly according to any one of the first to fourth aspects is configured such that at least one of the at least ten external splines has a first spline shape that is different from a second spline shape or spline shape of another of the at least ten external splines.

[0013] With the bicycle hub assembly according to the fifth aspect, the difference between the first spline shape and the second spline shape helps the user to correctly attach the rear bicycle sprocket assembly to the sprocket support body, particularly with regard to a circumferential position of each sprocket of the rear sprocket assembly.

[0014] According to a sixth aspect of the present invention, the bicycle hub assembly according to any one of the first to fifth aspects is configured such that at least one of the at least ten external splines has a first spline size that is different from a second spline size of another of the at least ten external splines.

[0015] With the bicycle hub assembly according to the sixth aspect, the difference between the first spline size and the second spline size helps the user to correctly attach the rear bicycle sprocket assembly to the sprocket support body, particularly with regard to a circumferential position of each sprocket of the rear sprocket assembly.

[0016] According to a seventh aspect of the present invention, the bicycle hub assembly according to any one of the first to sixth aspects is configured such that the at least ten external splines each have a maximum circumferential width. A total of the maximum circumferential widths is equal to or greater than 55 mm.

[0017] With the bicycle hub assembly according to the seventh aspect, it is possible to improve the strength of the at least ten external splines in a shear direction.

[0018] According to an eighth aspect of the present invention, the bicycle hub assembly according to the present invention is configured such that the total sum of the maximum circumferential widths is equal to or greater than 60 mm.

[0019] With the bicycle hub assembly according to the eighth aspect, it is possible to further improve the strength of the at least ten external splines in a shear direction.

[0020] According to a ninth aspect of the present invention, the bicycle hub assembly is configured such that the total sum of the maximum circumferential widths is equal to or greater than 65 mm.

[0021] With the bicycle hub assembly according to the ninth aspect, it is possible to further improve the strength of the at least ten external splines in a shear direction.

[0022] According to a tenth aspect of the present invention, a bicycle hub assembly includes a sprocket support body. The sprocket support body includes a plurality of external splines. At least two external splines of the plurality of external splines are circumferentially arranged at a first outer helix angle with respect to a rotational center axis of the bicycle hub assembly. The first outer helix angle ranges from 10 degrees to 20 degrees. Each of the at least ten external splines includes the external spline drive surface for receiving a driving rotational force from the rear bicycle sprocket assembly upon pedaling, wherein the plurality of external spline drive surfaces each include a radially outermost edge, a radially innermost edge, and a radial length defined from the radially outermost edge to the radially innermost edge, and wherein a total sum of the radial lengths of the external spline drive surfaces is equal to or greater than 7 mm.

[0023] In the bicycle hub assembly according to the tenth aspect, the first outer pitch angle reduces a rotational force applied to each of the at least two outer splines compared to a sprocket support body having an outer pitch angle greater than the first outer pitch angle. This improves the durability of the sprocket support body and / or improves the degree of freedom in selecting a material for the sprocket support body without reducing the durability of the sprocket support body.

[0024] According to an eleventh aspect of the present invention, the bicycle hub assembly according to the tenth aspect is configured such that the first outer pitch angle is in the range of 12 degrees to 15 degrees.

[0025] With the bicycle hub assembly according to the eleventh aspect, the first outer pitch angle reduces a rotational force applied to each of the at least two outer splines compared to a sprocket support body having an outer pitch angle greater than the first outer pitch angle. This further improves the durability of the sprocket support body and / or increases the degree of freedom in selecting the material of the sprocket support body without reducing the durability of the sprocket support body.

[0026] According to a thirteenth aspect of the present invention, the bicycle hub assembly according to any one of the tenth to twelfth aspects is configured such that at least two outer spline teeth of the plurality of outer spline teeth are arranged in the circumferential direction at a second outer pitch angle relative to the rotational center axis of the bicycle hub assembly. The second outer pitch angle is different from the first outer pitch angle.

[0027] With the bicycle hub assembly according to the thirteenth aspect, the difference between the first outer pitch angle and the second outer pitch angle helps the user to correctly attach the rear bicycle sprocket assembly to the sprocket support body, particularly with respect to a circumferential position of each sprocket of the rear bicycle sprocket assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] A more complete appreciation of the invention and many of the attendant advantages will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings. Fig. 1 is a schematic diagram of a bicycle drivetrain according to one embodiment. Fig. 2 is an exploded perspective view of the Fig. 1 illustrated bicycle drivetrain. Fig. 3 is another perspective view of the Fig. 2 illustrated bicycle drivetrain. Fig. 4 is a cross-sectional view of the bicycle drive train along the line IV-IV of Fig. 2. Fig. 5 is an exploded perspective view of a bicycle hub assembly of the Fig. 2 illustrated bicycle drivetrain. Fig. 6 is an enlarged cross-sectional view of the bicycle drive train shown in Fig. 4 is shown. Fig. 7 is a perspective view of a sprocket support body of the bicycle hub assembly of the Fig. 2 illustrated bicycle drivetrain. Fig. 8 is another perspective view of the sprocket support body of the bicycle hub assembly of the Fig. 2 illustrated bicycle drivetrain. Fig. 9 is a side elevation view of the Fig. 7 shown sprocket support body. Fig. 10 is a side elevational view of a sprocket support body of the bicycle hub assembly according to a modification. Fig. 11 is an enlarged cross-sectional view of the Fig. 7 shown sprocket support body. Fig. 12 is a cross-sectional view of the Fig. 7 shown sprocket support body. Fig. 13 is a perspective view of the bicycle hub assembly of the Fig. 2 illustrated bicycle drivetrain. Fig. 14 is a side elevational view of the bicycle hub assembly of the Fig. 2 illustrated bicycle drivetrain. Fig. 15 is a rear view of the bicycle hub assembly of the Fig. 2 illustrated bicycle drivetrain. Fig. 16 is a cross-sectional view of the bicycle hub assembly taken along line XVI-XVI of Fig. 5. Fig. 17 is a side elevational view of the rear bicycle sprocket assembly of the Fig. 2 illustrated bicycle drivetrain. Fig. 18 is an exploded perspective view of the Fig. 17 shown rear bicycle sprocket arrangement. Fig. 19 is a partially exploded perspective view of the Fig. 17 shown rear bicycle sprocket arrangement. Fig. 20 is another perspective partially exploded view of the Fig. 17 shown rear bicycle sprocket arrangement. Fig. 21 is another perspective partially exploded view of the Fig. 17 shown rear bicycle sprocket arrangement. Fig. 22 is another perspective partially exploded view of the Fig. 17 shown rear bicycle sprocket arrangement. Fig. 23 is a perspective cross-sectional view of the rear bicycle sprocket assembly taken along line XXIII-XXIII of Fig. 17. Fig. 24 is a perspective view of a smallest sprocket of the Fig. 17 shown bicycle sprocket arrangement. Fig. 25 is another perspective view of the smallest sprocket of the Fig. 17 shown bicycle sprocket arrangement. Fig. 26 is a side elevation view of the smallest sprocket of the Fig. 17 shown bicycle sprocket arrangement. Fig. Figure 27 is a side elevational view of a smallest sprocket after modification. Fig. 28 is an enlarged cross-sectional view of the Fig. 24 shown smallest sprocket. Fig. 29 is a cross-sectional view of the smallest in Fig. 24 shown sprocket. Fig. 30 is a cross-sectional view of the sprocket support body and the smallest sprocket of the Fig. 2 illustrated bicycle drivetrain. Fig. 31 is a partially exploded perspective view of the bicycle rear sprocket assembly shown in FIG. 17. Fig. 32 is a perspective view of a sprocket support of the Fig. 17 shown rear bicycle sprocket arrangement. DESCRIPTION OF THE EMBODIMENTS

[0029] The embodiment(s) will now be described with reference to the accompanying drawings, wherein like reference numerals designate corresponding or identical elements in the various drawings.

[0030] With initial reference to Fig. 1, a bicycle drivetrain 10 according to one embodiment includes a bicycle hub assembly 12 and a bicycle rear sprocket assembly 14. The bicycle hub assembly 12 is attached to a bicycle frame BF. The bicycle rear sprocket assembly 14 is mounted on the bicycle hub assembly 12. A bicycle brake rotor 16 is mounted on the bicycle hub assembly 12.

[0031] The bicycle drivetrain 10 further includes a crank assembly 18 and a bicycle chain 20. The crank assembly 18 includes a crank axle 22, a right crank arm 24, a left crank arm 26, and a front sprocket 27. The right crank arm 24 and the left crank arm 26 are attached to the crank axle 22. The front sprocket 27 is attached to at least one of the crank axle 22 and the right crank arm 24. The bicycle chain 20 is connected to the front sprocket 27 and the rear bicycle sprocket assembly 14 to transmit pedaling power from the front sprocket 27 to the rear bicycle sprocket assembly 14. The crank assembly 18, in the illustrated embodiment, includes the sprocket 27 as a single sprocket. However, the crank assembly 18 may include multiple front sprockets. The rear bicycle sprocket assembly 14 is a rear sprocket assembly.However, structures of the rear bicycle sprocket assembly 14 may be applied to the front sprocket.

[0032] In the present application, the following directional terms "front," "rear," "forward," "backward," "left," "right," "across," "up," and "down," as well as other similar directional terms, refer to those directions determined from the perspective of the user (e.g., the cyclist) sitting on a saddle (not shown) of a bicycle and facing the handlebars (not shown). Accordingly, as used to describe the bicycle drivetrain 10, the bicycle hub assembly 12, or the bicycle rear sprocket assembly 14, these terms should be construed with reference to the bicycle equipped with the bicycle drivetrain 10, the bicycle hub assembly 12, or the bicycle rear sprocket assembly 14, as used in an upright riding position on a horizontal surface.

[0033] As in Fig. 2 and Fig. 3, the bicycle hub assembly 12 and the rear bicycle sprocket assembly 14 have a rotational center axis A1. The rear bicycle sprocket assembly 14 is fixed by the bicycle hub assembly 12 with respect to the bicycle frame BF ( Fig. 1) is rotatably supported about the rotational center axis A1. The rear bicycle sprocket assembly 14 is configured to engage the bicycle chain 20 to transmit a driving rotational force between the bicycle chain 20 and the rear bicycle sprocket assembly 14 during pedaling. The rear bicycle sprocket assembly is rotated about the rotational center axis A1 in a driving rotational direction D11 during pedaling. The driving rotational direction D11 is defined along a circumferential direction D1 of the bicycle hub assembly 12 or the rear bicycle sprocket assembly 14. A reverse rotational direction D12 is an opposite direction to the driving rotational direction D11 and is defined along the circumferential direction D1.

[0034] As in Fig. 2, the bicycle hub assembly 12 includes a sprocket support body 28. The rear bicycle sprocket assembly is secured to the sprocket support body 28 to transmit the driving rotational force F1 between the sprocket support body 28 and the rear bicycle sprocket assembly. The bicycle hub assembly 12 further includes a hub axle 30. The sprocket support body 28 is rotatably secured to the hub axle 30 about the rotational center axis A1. The bicycle hub assembly 12 includes a locking ring 32. The locking ring 32 is secured to the sprocket support body 28 to retain the rear bicycle sprocket assembly 14 relative to the sprocket support body 28 in an axial direction D2 parallel to the rotational center axis A1.

[0035] As in Fig. As shown in Figure 4, the bicycle hub assembly 12 is attached to the bicycle frame BF with a wheel attachment structure WS. The hub axle 30 has a through hole 30A. A mounting rod WS1 of the wheel attachment structure WS extends through the hole 30A of the hub axle 30. The hub axle 30 includes a first axle end 30B and a second axle end 30C. The hub axle 30 extends between the first axle end 30B and the second axle end 30C along the rotational center axis A1. The first axle end 30B is provided in a first recess BF11 of a first frame BF1 of the bicycle frame BF. The second axle end 30C is provided in a second recess BF21 of a second frame BF2 of the bicycle frame BF. The hub axle 30 is held between the first frame BF1 and the second frame BF2 by the wheel securing structure WS. The wheel securing structure WS comprises a structure known in the bicycle field.Therefore, for the sake of brevity, it will not be described in detail.

[0036] As in Fig. 4 and Fig. 5, the bicycle hub assembly 12 further includes a brake rotor support body 34. The brake rotor support body 34 is rotatably mounted on the hub axle 30 about the rotational center axis A1. The brake rotor support body 34 is connected to the bicycle brake rotor 16 ( Fig. 1) to transmit a braking torque from the bicycle brake rotor 16 to the brake rotor support body 34.

[0037] As in Fig. 5, the bicycle hub assembly 12 further includes a hub body 36. The hub body 36 is rotatably mounted to the hub axle 30 about the rotational center axis A1. In this embodiment, the sprocket support body 28 is a separate member from the hub body 36. The brake rotor support body 34 is provided integrally with the hub body 36 as a one-piece unitary member. However, the sprocket support body may be provided integrally with the hub body 36. The brake rotor support body 34 may be a separate member from the hub body 36.

[0038] The hub body 36 includes a first flange 36A and a second flange 36B. First spokes (not shown) are connected to the first flange 36A. Second spokes (not shown) are connected to the second flange 36B. The second flange 36B is spaced from the first flange 36A in the axial direction D2. The first flange 36A is provided in the axial direction D2 between the sprocket support body 28 and the second flange 36B. The second flange 36B is provided in the axial direction D2 between the first flange 36A and the brake rotor support body 34.

[0039] The locking ring 32 includes an externally threaded portion 32A. The sprocket support body 28 has an internally threaded portion 28A. The externally threaded portion 32A is threadably engaged with the internally threaded portion 28A in a state in which the locking ring 32 is fixed to the sprocket support body 28.

[0040] As in Fig. 6, the bicycle hub assembly 12 further comprises a pawl structure 38. The sprocket support body 28 is operatively connected to the hub body 36 via the pawl structure 38. The pawl structure 38 is configured to connect the sprocket support body 28 to the hub body 36 in order to rotate the sprocket support body 28 together with the hub body 36 in the drive rotation direction D11 ( Fig. 5). The pawl structure 38 is configured to allow the sprocket support body 28 to rotate relative to the hub body 36 in the reverse rotation direction D12 ( Fig. 5). Accordingly, the pawl structure 38 can be described as a one-way clutch structure 38. The pawl structure 38 includes structures known in the bicycle field. Therefore, for the sake of brevity, they will not be described in detail here.

[0041] The bicycle hub assembly 12 includes a first bearing 39A and a second bearing 39B. The first bearing 39A and the second bearing 39B are provided between the sprocket support body 28 and the hub axle 30 to rotatably support the sprocket support body 28 with respect to the hub axle 30 about the rotational center axis A1.

[0042] In this embodiment, each of the sprocket support body 28, the brake rotor support body 34, and the hub body 36 is made of a metallic material such as aluminum, iron, or titanium. However, at least one of the sprocket support body 28, the brake rotor support body 34, and the hub body 36 may be made of a non-metallic material.

[0043] As in Fig. 7 and Fig. 8, the sprocket support body 28 includes at least one external spline tooth 40 adapted to engage the rear bicycle sprocket assembly 14 ( Fig. 6). The sprocket support body 28 includes a plurality of external spline teeth 40 adapted to engage the rear bicycle sprocket assembly 14 ( Fig. 6). That is, the at least one external spline tooth 40 comprises a plurality of external spline teeth 40. The sprocket support body 28 comprises at least nine external spline teeth 40 which are configured to mesh with the rear bicycle sprocket assembly 14 ( Fig. 6). The sprocket support body 28 includes at least ten external spline teeth 40 configured to mesh with the rear bicycle sprocket assembly 14 ( Fig. 6) to intervene.

[0044] The sprocket support body 28 includes a base support 41 having a tubular shape. The base support 41 extends along the rotational center axis A1. The external spline tooth 40 extends radially outward from the base support 41. The sprocket support body 28 includes a larger diameter portion 42, a flange 44, and a plurality of spiral external spline teeth 46. The larger diameter portion 42 and the flange 44 extend radially outward from the base support 41. The larger diameter portion 42 is provided between the plurality of external spline teeth 40 and the flange 44 in the axial direction D2. The larger diameter portion 42 and the flange 44 are provided between the plurality of external spline teeth 40 and the plurality of spiral external spline teeth 46 in the axial direction D2. As shown in Fig. As can be seen in Figure 6, the rear bicycle sprocket assembly 14 is retained in the axial direction D2 between the larger diameter portion 42 and a locking flange 32B of the locking ring 32. The larger diameter portion 42 may have an internal cavity so that a drive structure, such as a one-way clutch structure, may be contained within the internal cavity. The larger diameter portion 42 may be omitted from the bicycle hub assembly 12 as desired.

[0045] As in Fig. 9, the total number of the at least ten external spline teeth 40 is equal to or greater than 20. The total number of the at least ten external spline teeth 40 is equal to or greater than 25. In this embodiment, the total number of the external spline teeth 40 is 26. However, the total number of the external spline teeth 40 is not limited to this embodiment and the above ranges.

[0046] The at least ten external spline teeth 40 have a first outer pitch angle PA11 and a second outer pitch angle PA12. At least two outer spline teeth of the plurality of external spline teeth are arranged at the first outer pitch angle PA11 with respect to the rotational center axis A1 of the bicycle hub assembly 12 in the circumferential direction. At least two outer spline teeth of the plurality of external spline teeth 40 are arranged at the second pitch angle PA12 in the circumferential direction with respect to the rotational center axis A1 of the bicycle hub assembly 12. In this embodiment, the second outer pitch angle PA12 differs from the first outer pitch angle PA11. However, the second outer pitch angle PA12 may be substantially equal to the first outer pitch angle PA11.

[0047] In this embodiment, the external spline teeth 40 are arranged at the first outer pitch angle PA11 in the circumferential direction D1. Two external spline teeth of the external spline teeth 40 are arranged at the second outer pitch angle PA12 in the circumferential direction D1. However, at least two external spline teeth of the external spline teeth 40 can be arranged at a different outer angle in the circumferential direction D1.

[0048] The first outer pitch angle PA11 ranges from 10 degrees to 20 degrees. The first outer pitch angle PA11 ranges from 12 degrees to 15 degrees. The first outer pitch angle PA11 ranges from 13 degrees to 14 degrees. In this embodiment, the first outer pitch angle PA11 is 13.3 degrees. However, the first outer pitch angle PA11 is not limited to this embodiment and the above ranges.

[0049] The second outer pitch angle PA12 ranges from 5 degrees to 30 degrees. In this embodiment, the second outer pitch angle PA12 is 26 degrees. However, the second outer pitch angle PA12 is not limited to this embodiment and the above range.

[0050] The external spline teeth 40 have substantially the same shape. The external spline teeth 40 have substantially the same spline size. The external spline teeth 40 have substantially the same profile when viewed along the rotational center axis A1. As shown in Fig. 10, however, at least one of the at least ten external splines 40 may have a first spline shape that differs from a second spline shape of another of the at least ten external splines 40. At least one of the at least ten external splines 40 may have a first spline size that differs from a second spline size of another of the at least ten external splines 40. At least one of the at least ten external splines 40 may have a profile that differs from a profile of another of the at least ten external splines 40 when viewed along the rotational center axis A1. In Fig. 10, one of the external spline teeth 40 has a spline shape that differs from a spline shape of the other teeth of the external spline teeth 40. One of the external spline teeth 40 has a spline size that differs from a spline size of the other teeth of the external spline teeth 40. One of the external spline teeth 40 has a profile that differs from a profile of the other teeth of the external spline teeth 40 when viewed along the rotational center axis A1.

[0051] As in Fig. 11, each of the at least 40 external spline teeth has an external spline drive surface 48 and an external spline non-drive surface 50. The plurality of external spline teeth 40 includes a plurality of external spline drive surfaces 48 for transmitting the rotational drive force F1 from the rear bicycle sprocket assembly 14 ( Fig. 6) during pedaling. The plurality of external spline teeth 40 include a plurality of external spline non-drive surfaces 50. The external spline drive surface 48 is contactable with the rear bicycle sprocket assembly 14 to receive the drive torque F1 from the rear bicycle sprocket assembly 14 ( Fig. 6) during pedaling. The external spline drive surface 48 faces the reverse rotation direction D12. The external spline non-drive surface 50 is provided on a rear side of the external spline drive surface 48 in the circumferential direction D1. The external spline non-drive surface 50 faces the drive rotation direction D11 so as not to receive the drive rotational force F1 from the rear bicycle sprocket assembly 14 during pedaling.

[0052] The at least 40 external splines each have a maximum circumferential width MW1. The external splines 40 each have a maximum circumferential width MW1. The maximum circumferential width MW1 is defined as a maximum width to accommodate a compressive force F2 applied to the external spline 40. The maximum circumferential width MW1 is defined as a straight distance based on the spline drive surface 48.

[0053] The plurality of splined drive surfaces 48 each have a radially outermost edge 48A and a radially innermost edge 48B. The external splined drive surface 48 extends from the radially outermost edge 48A to the radially innermost edge 48B. A first reference circle is defined at the radially innermost edge 48B and is centered on the rotational center axis A1. The first reference circle RC11 intersects the external splined non-drive surface 50 at a reference point 50R. The maximum circumferential width MW1 extends from the radially innermost edge 48B to the reference point 50R in the circumferential direction D1.

[0054] The plurality of external spline non-drive surfaces 50 each have a radially outermost edge 50A and a radially innermost edge 50B. The spline non-drive surface 50 extends from the radially outermost edge 50A to the radially innermost edge 50B. The reference point 50R is provided between the radially outermost edge 50A and the radially innermost edge 50B. However, the reference point 50R may coincide with the radially innermost edge 50B.

[0055] A total of the maximum circumferential widths MW1 is equal to or greater than 55 mm. The total of the maximum circumferential widths MW1 is equal to or greater than 60 mm. The total of the maximum circumferential widths MW1 is equal to or greater than 65 mm. In this embodiment, the total of the maximum circumferential widths MW1 is 68 mm. However, the total of the maximum circumferential widths MW1 is not limited to this embodiment and the above ranges.

[0056] As in Fig. As can be seen in Figure 12, the at least one external spline 40 has an external spline major diameter DM11. The external spline major diameter DM11 is equal to or greater than 25 mm. The external spline major diameter DM11 is equal to or greater than 29 mm. The external spline major diameter DM11 is equal to or less than 30 mm. In this embodiment, the external spline major diameter DM11 is 29.6 mm. However, the external spline major diameter DM11 is not limited to this embodiment and the above ranges.

[0057] The at least one external spline tooth 40 has an external spline minor diameter DM12. The at least one external spline tooth 40 has an external spline root circle RC12 with the external spline minor diameter DM12. However, the external spline root circle RC12 can have a different diameter than the external spline minor diameter DM12. The external spline minor diameter DM12 is equal to or less than 28 mm. The external spline minor diameter DM12 is equal to or greater than 25 mm. The external spline minor diameter DM12 is equal to or greater than 27 mm. In this embodiment, the external spline minor diameter DM12 is 27.2 mm. However, the external spline minor diameter DM12 is not limited to this embodiment and the above ranges.

[0058] The larger diameter portion 42 has an outer diameter DM13 that is larger than the outer diameter of the external spline main diameter DM11. The outer diameter DM13 ranges between 32 mm and 40 mm. In this embodiment, the outer diameter DM13 is 35 mm. However, the outer diameter DM13 is not limited to this embodiment.

[0059] As in Fig. 11, the plurality of external spline drive surfaces 48 each include a radial length RL11 defined from the radially outermost edge 48A to the radially innermost edge 48B. The total of the radial lengths RL11 of the plurality of external spline drive surfaces 48 is equal to or greater than 7 mm. The total of the radial lengths RL11 is equal to or greater than 10 mm. The total of the radial lengths RL11 is equal to or greater than 15 mm. In this embodiment, the total of the radial lengths RL11 is 19.5 mm. However, the total of the radial lengths RL11 is not limited to this embodiment.

[0060] The plurality of external splines 40 have an additional radial length RL12. The additional radial lengths RL12 are each defined from the external spline root circle RC12 to the radially outermost ends 40A of the plurality of external splines 40. The total of the additional radial lengths RL12 is equal to or greater than 12 mm. In this embodiment, the total of the additional radial lengths RL12 is 31.85 mm. However, the total of the additional radial lengths RL12 is not limited to this embodiment.

[0061] At least one of the at least nine external splines 40 has an asymmetric shape with respect to a circumferential tooth tip centerline CL1. The circumferential tooth tip centerline CL1 is a line connecting the rotational center axis A1 and a circumferential center point CP1 of the radially outermost end 40A of the external spline 40. However, at least one of the external splines 40 may have a symmetric shape with respect to the circumferential tooth tip centerline CL1. The at least one of the at least nine external splines 40 includes the external spline drive surface 48 and the external spline non-drive surface 50.

[0062] The external spline drive surface 48 has a first external spline face angle AG11. The first external spline face angle AG11 is defined between the external spline drive surface 48 and a first radial line L11. The first radial line L11 extends from the rotational center axis A1 of the bicycle hub assembly 12 to the radially outermost edge 48A of the external spline drive surface 48. The first outer pitch angle PA11 or the second outer pitch angle PA12 is defined between the adjacent first radial lines L11 (see, for example, Fig. 9).

[0063] The external spline non-drive surface 50 has a second external spline surface angle AG12. The second external spline surface angle AG12 is defined between the external spline non-drive surface 50 and a second radial line L12. The second radial line L12 extends from the rotational center axis A1 of the bicycle hub assembly 12 to the radially outermost edge 50A of the external spline non-drive surface 50.

[0064] In this embodiment, the second external spline face angle AG12 differs from the first external spline face angle AG11. The first external spline face angle AG11 is smaller than the second external spline face angle AG12. However, the first external spline face angle AG11 may be equal to or greater than the second external spline face angle AG12.

[0065] The first external spline angle AG11 is in the range of 0 degrees to 10 degrees. The second external spline face angle AG12 is in the range of 0 degrees to 60 degrees. In this embodiment, the first external spline face angle AG11 is 5 degrees. The second external spline face angle AG12 is 45 degrees. However, the first external spline face angle AG11 and the second external spline face angle AG12 are not limited to this embodiment and the above ranges.

[0066] As in the Fig. 13 and Fig. 14, the brake rotor support body 34 has at least one additional external spline tooth 52 which is adapted to engage with the bicycle brake rotor 16 ( Fig. 4). In this embodiment, the brake rotor support body 34 includes an additional base support 54 and a plurality of additional external splines 52. The additional base support 54 has a tubular shape and extends from the hub body 36 along the rotational center axis A1. The additional external spline 52 extends radially outward from the additional base support 54. A total number of the additional external spline teeth 52 is 52. However, the total number of the additional external spline teeth 52 is not limited to this embodiment.

[0067] As in Fig. 14, the at least one additional external spline tooth has an additional external spline main diameter DM14. As shown in Fig. As can be seen in Figure 15, the additional external spline major diameter DM14 is larger than the external spline major diameter DM11. The additional external spline major diameter DM14 is substantially equal to the outer diameter DM13 of the larger-diameter part 42. However, the additional external spline major diameter DM14 may be equal to or smaller than the external spline major diameter DM11. The additional external spline major diameter DM14 may be different from the outer diameter DM13 of the larger-diameter part 42.

[0068] As in Fig. As shown in Figure 16, the hub axle 30 includes an axial contact surface 30B1 for contacting the bicycle frame BF. In this embodiment, the axial contact surface 30B1 is contactable with the first frame BF1 of the bicycle frame BF. The first frame BF1 has a frame contact surface BF12. The axial contact surface 30B1 is in contact with the frame contact surface BF12 in a state in which the bicycle hub assembly 12 is attached to the bicycle frame BF with the wheel attachment structure WS.

[0069] A first axial length AL11 is defined from the axial contact surface 30B1 to the larger diameter part 42 in the axial direction D2 with respect to the rotational center axis A1. The first axial length AL11 ranges from 35 mm to 41 mm. The first axial length AL11 may be equal to or greater than 39 mm. The first axial length AL11 may also be in the range of 35 mm to 37 mm. In this embodiment, the first axial length AL11 is 36.2 mm. However, the first axial length AL11 is not limited to this embodiment and the above ranges.

[0070] The larger diameter portion 42 has an axial end 42A that is farthest from the axial contact surface 30B1 in the axial direction D2. A second axial length AL12 is defined from the axial contact surface 30B1 to the axial end 42A in the axial direction D2. The second axial length AL12 ranges from 38 mm to 47 mm. The second axial length AL12 may range from 44 mm to 45 mm. The second axial length AL12 may also range from 40 mm to 41 mm. In this embodiment, the second axial length AL12 is 40.75 mm. However, the second axial length AL12 is not limited to this embodiment and the above ranges.

[0071] An axial length AL13 of the larger diameter part 42 is in the range of 3 mm to 6 mm. In this embodiment, the axial length AL13 is 4.55 mm. However, the axial length AL13 is not limited to this embodiment and the above ranges.

[0072] As in Fig. As seen in Figure 17, the rear bicycle sprocket assembly 14 includes at least one sprocket. The at least one sprocket includes a smallest sprocket SP1 and a largest sprocket SP12. The smallest sprocket SP1 may also be referred to as sprocket SP1. The largest sprocket SP12 may also be referred to as sprocket SP12. In this embodiment, the at least one sprocket further includes sprockets SP2 to SP11. The sprocket SP1 corresponds to the highest gear. The sprocket SP12 corresponds to a low gear. A total number of sprockets of the rear bicycle sprocket assembly 14 is not limited to this embodiment.

[0073] The smallest sprocket SP1 includes at least one sprocket tooth SP1B. A total number of the at least one sprocket tooth SP1B of the smallest sprocket SP1 is equal to or less than 10. In this embodiment, the total number of the at least one sprocket tooth SP1B of the smallest sprocket SP1 is 10. However, the total number of the at least one sprocket tooth SP1B of the smallest sprocket SP1 is not limited to this embodiment and the above range.

[0074] The largest sprocket SP12 includes at least one sprocket tooth SP12B. A total number of the at least one sprocket tooth SP12B of the largest sprocket SP12 is equal to or greater than 46. The total number of the at least one sprocket tooth SP12B of the largest sprocket SP12 is equal to or greater than 50. In this embodiment, the total number of the at least one sprocket tooth SP12B of the largest sprocket SP12 is 51. However, the total number of the at least one sprocket tooth SP12B of the largest sprocket SP12 is not limited to this embodiment and the above ranges.

[0075] The sprocket SP2 comprises at least one sprocket tooth SP2B. The sprocket SP3 comprises at least one sprocket tooth SP3B. The sprocket SP4 comprises at least one sprocket tooth SP4B. The sprocket SP5 comprises at least one sprocket tooth SP5B. The sprocket SP6 comprises at least one sprocket tooth SP6B. The sprocket SP7 comprises at least one sprocket tooth SP7B. The sprocket SP8 comprises at least one sprocket tooth SP8B. The sprocket SP9 comprises at least one sprocket tooth SP9B. The sprocket SP10 comprises at least one sprocket tooth SP10B. The sprocket SP11 comprises at least one sprocket tooth SP11B.

[0076] A total number of the at least one sprocket tooth SP2B is 12. A total number of the at least one sprocket tooth SP3B is 14. A total number of the at least one sprocket tooth SP4B is 16. A total number of the at least one sprocket tooth SP5B is 18. A total number of the at least one sprocket tooth SP6B is 21. A total number of the at least one sprocket tooth SP7B is 24. A total number of the at least one sprocket tooth SP8B is 28. A total number of the at least one sprocket tooth SP9B is 33. A total number of the at least one sprocket tooth SP10B is 39. A total number of the at least one sprocket tooth SP11B is 45. The total number of the sprocket teeth SP2 to SP11 is not limited to this embodiment.

[0077] As in Fig. 18, the sprockets SP1 through SP12 are separate elements. However, at least one of the sprockets SP1 through SP12 may be provided at least partially integrally with another of the sprockets SP1 through SP12. The rear bicycle sprocket assembly 14 includes a sprocket mount 56, a plurality of spacers 58, a first ring 59A, and a second ring 59B. The sprockets SP1 through SP12 are mounted to the sprocket mount 56 in the illustrated embodiment.

[0078] As in Fig. 19, the sprocket SP1 includes a sprocket body SP1A and the plurality of sprocket teeth SP1B. The plurality of sprocket teeth SP1B extend radially outward from the sprocket body SP1A. The sprocket SP2 includes a sprocket body SP2A and the plurality of sprocket teeth SP2B. The plurality of sprocket teeth SP2B extend radially outward from the sprocket body SP2A. The sprocket SP3 includes a sprocket body SP3A and the plurality of sprocket teeth SP3B. The plurality of sprocket teeth SP3B extend radially outward from the sprocket body SP3A. The sprocket SP4 includes a sprocket body SP4A and the plurality of sprocket teeth SP4B. The plurality of sprocket teeth SP4B extend radially outward from the sprocket body SP4A. The sprocket SP5 includes a sprocket body SP5A and the plurality of sprocket teeth SP5B. The plurality of sprocket teeth SP5B extend radially outward from the sprocket body SP5A.The first ring 59A is provided between the sprockets SP3 and SP4. The second ring 59B is provided between the sprockets SP4 and SP5.

[0079] As in Fig. As seen in Figure 20, the sprocket SP6 includes a sprocket body SP6A and the plurality of sprocket teeth SP6B. The plurality of sprocket teeth SP6B extend radially outward from the sprocket body SP6A. The sprocket SP7 includes a sprocket body SP7A and the plurality of sprocket teeth SP7B. The plurality of sprocket teeth SP7B extend radially outward from the sprocket body SP7A. The sprocket SP8 includes a sprocket body SP8A and the plurality of sprocket teeth SP8B. The plurality of sprocket teeth SP8B extend radially outward from the sprocket body SP8A.

[0080] As in Fig. 21, the sprocket SP9 includes a sprocket body SP9A and the plurality of sprocket teeth SP9B. The plurality of sprocket teeth SP9B extend radially outward from the sprocket body SP9A. The sprocket SP10 includes a sprocket body SP10A and the plurality of sprocket teeth SP10B. The plurality of sprocket teeth SP10B extend radially outward from the sprocket body SP10A. The sprocket SP11 includes a sprocket body SP11A and the plurality of sprocket teeth SP11B. The plurality of sprocket teeth SP11B extend radially outward from the sprocket body SP11A. The sprocket SP12 includes a sprocket body SP12A and the plurality of sprocket teeth SP12B. The plurality of sprocket teeth SP12B extend radially outward from the sprocket body SP12A.

[0081] As in Fig. As seen in Figure 22, the sprocket mount 56 includes a hub engaging portion 60 and a plurality of support arms 62. The plurality of support arms 62 extend radially outward from the hub engaging portion 60. The support arm 62 includes first through eighth attachment portions 62A through 62H. The plurality of spacers 58 includes a plurality of first spacers 58A, a plurality of second spacers 58B, a plurality of third spacers 58C, a plurality of fourth spacers 58D, a plurality of fifth spacers 58E, a plurality of sixth spacers 58F, and a plurality of seventh spacers 58G.

[0082] As in Fig. As shown in Figure 23, the first spacers 58A are provided between the sprockets SP5 and SP6. The second spacers 58B are provided between the sprockets SP6 and SP7. The third spacers 58C are provided between the sprockets SP7 and SP8. The fourth spacers 58D are provided between the sprockets SP8 and SP9. The fifth spacers 58E are provided between the sprockets SP9 and SP10. The sixth spacers 58F are provided between the sprockets SP10 and SP11. The seventh spacers 58G are provided between the sprockets SP11 and SP12.

[0083] The sprocket SP6 and the first spacer 58A are attached to the first attachment portion 62A with a bonding structure such as an adhesive. The sprocket SP7 and the second spacer 58B are attached to the second attachment portion 62B with a bonding structure such as an adhesive. The sprocket SP8 and the third spacer 58C are attached to the third attachment portion 62C with a bonding structure such as an adhesive. The sprocket SP9 and the spacer 58D are attached to the fourth attachment portion 62D with a bonding structure such as an adhesive. The sprocket SP10 and the fifth spacer 58E are attached to the fifth attachment portion 62E with a bonding structure such as an adhesive. The sprocket SP11 and the sixth spacer 58F are attached to the sixth attachment portion 62F with a bonding structure such as an adhesive.The sprocket SP12 and the seventh spacer 58G are fixed to the seventh fixing portion 62G with a bonding structure such as an adhesive. The sprocket SP5 and the second ring 59B are fixed to the eighth fixing portion 62H with a bonding structure such as an adhesive. The hub engaging portion 60, the sprockets SP1 to SP4, the first ring 59A, and the second ring 59B are held in the axial direction D2 between the larger diameter portion 42 and the locking flange 32B of the locking ring 32.

[0084] In this embodiment, each of the springs SP1 to SP12 is made of a metallic material such as aluminum, iron, or titanium. Each of the sprocket supports 56, the first to seventh spacers 58A to 58G, the first ring 59A, and the second ring 59B is made of a non-metallic material such as a resin material. However, at least one of the springs SP1 to SP12 may be made at least partially of a non-metallic material. At least one of the sprocket supports 56, the first to seventh spacers 58A to 58G, the first ring 59A, and the second ring 59B may be made at least partially of a metallic material such as aluminum, iron, or titanium.

[0085] The at least one sprocket has at least one internal spline tooth configured to engage the bicycle hub assembly 12. As shown in Fig. 24 and Fig. 25, the at least one sprocket has at least ten internal spline teeth configured to engage the bicycle hub assembly 12. The at least one internal spline tooth has a plurality of internal spline teeth. Thus, the at least one sprocket has a plurality of internal spline teeth configured to engage the bicycle hub assembly 12. In this embodiment, the sprocket SP1 has at least ten internal spline teeth 64 configured to engage the bicycle hub assembly 12. In this embodiment, the sprocket SP1 has the internal spline teeth 64 configured to mesh with the external spline teeth 40 of the sprocket support body 28 of the bicycle hub assembly 12. The sprocket body SP1A has an annular shape. The internal spline teeth 64 extend radially inward from the sprocket body SP1A.

[0086] As in Fig. 26, the total number of internal spline teeth is equal to or greater than 20. The total number of internal spline teeth is equal to or greater than 25. In this embodiment, the total number of internal spline teeth 64 is 26. However, the total number of internal spline teeth is not limited to these embodiments and the above ranges.

[0087] The at least ten internal spline teeth 64 have a first inner pitch angle PA21 and a second inner pitch angle PA22. At least two internal spline teeth of the plurality of internal spline teeth 64 are arranged in the circumferential direction at a first inner pitch angle PA21 with respect to the rotational center axis A1 of the rear bicycle sprocket assembly 14. At least two internal spline teeth of the plurality of internal spline teeth 64 are arranged in the circumferential direction at a second inner pitch angle PA22 with respect to the rotational center axis A1. In this embodiment, the second inner pitch angle PA22 is different from the first inner pitch angle PA21. However, the second inner pitch angle PA22 may be substantially equal to the first inner pitch angle PA21.

[0088] In this embodiment, the inner spline teeth 64 are arranged circumferentially at the first inner pitch angle PA21 in the circumferential direction D1. Two inner spline teeth of the inner spline teeth 64 are arranged at the second inner pitch angle PA22 in the circumferential direction D1. However, at least two inner spline teeth of the inner spline teeth 64 may be arranged at a different inner pitch angle in the circumferential direction D1.

[0089] The first inner pitch angle PA21 ranges from 10 degrees to 20 degrees. The first inner pitch angle PA21 ranges from 12 degrees to 15 degrees. The first inner pitch angle PA21 ranges from 13 degrees to 14 degrees. In this embodiment, the first inner pitch angle PA21 is 13.3 degrees. However, the first inner pitch angle PA21 is not limited to this embodiment and the above ranges.

[0090] The second inner pitch angle PA22 is in the range of 5 degrees to 30 degrees. In this embodiment, the second inner pitch angle PA22 is 26 degrees. However, the second inner pitch angle PA22 is not limited to this embodiment and the above range.

[0091] At least one of the at least ten internal splines 64 has a first spline shape that differs from a second spline shape of another of the at least ten internal splines 64. At least one of the at least ten internal splines 64 has a first spline size that differs from a second spline size of another of the at least ten internal splines 64. At least one of the at least ten internal splines 64 has a cross-sectional shape that differs from a cross-sectional shape of another of the at least ten internal splines 64. As in Fig. However, as can be seen in Figure 27, the internal spline teeth 64 may have the same shape. The internal spline teeth 64 may have the same size. The internal spline teeth 64 may have the same cross-sectional shape.

[0092] As in Fig. 28, the at least one internal spline tooth 64 includes an internal spline or spline drive surface 66 and an internal spline non-drive surface 68. The at least one internal spline tooth 64 includes a plurality of internal spline teeth 64. The plurality of internal spline teeth 64 include a plurality of internal spline drive surfaces 66 for transmitting the drive torque F1 from the bicycle hub assembly 12 ( Fig. 6). The plurality of internal splines 64 include a plurality of internal spline non-drive surfaces 68. The internal spline drive surface 66 is contactable with the sprocket support body 28 to transmit the driving rotational force F1 from the sprocket SP1 to the sprocket support body 28 during pedaling. The internal spline drive surface 66 faces the driving rotational direction D11. The internal spline non-drive surface 68 is provided on a reverse side of the internal spline drive surface 66 in the circumferential direction D1. The internal spline non-drive surface 68 faces the reverse rotational direction D12 so as not to transmit the driving rotational force F1 from the sprocket SP1 to the sprocket support body 28 during pedaling.

[0093] The at least ten internal spline teeth 64 each have maximum circumferential widths MW2. The internal spline teeth 64 have maximum circumferential widths MW2. The maximum circumferential width MW2 is defined as a maximum width to accommodate a compressive force F3 applied to the internal spline tooth 64. The maximum circumferential width MW2 is defined as a straight distance based on the spline drive surface 66.

[0094] The internal spline drive surface 66 has a radially outermost edge 66A and a radially innermost edge 66B. The internal spline drive surface 66 extends from the radially outermost edge 66A to the radially innermost edge 66B. A second reference circle RC21 is defined at the radially outermost edge 66A and is centered on the rotational center axis A1. The second reference circle RC21 intersects the internal spline non-drive surface 68 at a reference point 68R. The maximum circumferential width MW2 extends in the circumferential direction D1 from the radially innermost edge 66B to the reference point 68R.

[0095] The external spline non-drive surface 68 has a radially outermost edge 68A and a radially innermost edge 68B. The external spline non-drive surface 68 extends from the radially outermost edge 68A to the radially innermost edge 68B. The reference point 68R is provided between the radially outermost edge 68A and the radially innermost edge 68B.

[0096] A total of the maximum circumferential widths MW2 is equal to or greater than 40 mm. The total of the maximum circumferential widths MW2 is equal to or greater than 45 mm. The total of the maximum circumferential widths MW2 is equal to or greater than 50 mm. In this embodiment, the total of the maximum circumferential widths MW2 is 50.8 mm. However, the total of the maximum circumferential widths MW2 is not limited to this embodiment.

[0097] As in Fig. 29, the at least one internal spline 64 has an internal spline major diameter DM21. The at least one internal spline has an internal spline root circle RC22 with the internal spline major diameter DM21. However, the internal spline root circle RC22 may have a diameter different from the internal spline major diameter DM21. The internal spline major diameter DM21 is equal to or less than 30 mm. The internal spline major diameter DM21 is equal to or greater than 25 mm. The internal spline major diameter DM21 is equal to or greater than 29 mm. In this embodiment, the internal spline major diameter DM21 is 29.8 mm. However, the internal spline major diameter DM21 is not limited to this embodiment and the above ranges.

[0098] The at least one internal spline 64 has an internal spline pitch diameter DM22 equal to or less than 28 mm. The internal spline pitch diameter DM22 is equal to or greater than 25 mm. The internal spline pitch diameter DM22 is equal to or greater than 27 mm. In this embodiment, the internal spline pitch diameter DM22 is 27.7 mm. However, the internal spline pitch diameter DM22 is not limited to this embodiment and the above ranges.

[0099] As in Fig. 28, the plurality of internal spline drive surfaces 66 include the radially outermost edge 66A and the radially innermost edge 66B. The plurality of internal spline drive surfaces 66 each include a radial length RL21 defined from the radially outermost edge 66A to the radially innermost edge 66B. A total of the radial lengths RL21 of the plurality of internal spline drive surfaces 66 is equal to or greater than 7 mm. The total of the radial lengths RL21 is equal to or greater than 10 mm. The total of the radial lengths RL21 is equal to or greater than 15 mm. In this embodiment, the total of the radial lengths RL21 is 19.5 mm. However, the total of the radial lengths RL21 is not limited to this embodiment and the above ranges.

[0100] The plurality of internal splines 64 have an additional radial length RL22. The additional radial lengths RL22 are each defined from the internal spline root circle RC22 to the radially innermost ends 64A of the plurality of internal splines 64. A total of the additional radial lengths RL22 is equal to or greater than 12 mm. In this embodiment, the total of the additional radial lengths RL22 is 27.95 mm. However, the total of the additional radial lengths RL22 is not limited to this embodiment and the above ranges.

[0101] At least one of the internal splines 64 has an asymmetric shape with respect to a circumferential tooth tip center line CL2. The circumferential tooth tip center line CL2 is a line connecting the rotational center axis A1 and a circumferential center point CP2 of the radially innermost end 64A of the internal spline 64. However, at least one of the internal splines 64 may have a symmetric shape with respect to the circumferential tooth tip center line CL2. The at least one of the internal splines 64 includes the internal spline drive surface 66 and the internal spline non-drive surface 68.

[0102] The internal spline drive surface 66 has a first internal spline face angle AG21. The first internal spline face angle AG21 is defined between the internal spline drive surface 66 and a first radial line L21. The first radial line L21 extends from the rotational center axis A1 of the rear bicycle sprocket assembly 14 to the radially outermost edge 66A of the internal spline drive surface 66. The first inner pitch angle PA21 or the second inner pitch angle PA22 is defined between adjacent first radial lines L21 (see, e.g., Fig. 26).

[0103] The internal spline non-drive surface 68 has a second internal spline surface angle AG22. The second internal spline surface angle AG22 is defined between the internal spline non-drive surface 68 and a second radial line L22. The second radial line L22 extends from the rotational center axis A1 of the rear bicycle sprocket assembly 14 to the radially outermost edge 68A of the internal spline non-drive surface 68.

[0104] In this embodiment, the second internal spline face angle AG22 differs from the first internal spline face angle AG21. The first internal spline face angle AG21 is smaller than the second internal spline face angle AG22. However, the first internal spline face angle AG21 may be equal to or greater than the second internal spline face angle AG22.

[0105] The first internal spline face angle AG21 is in the range of 0 degrees to 10 degrees. The second internal spline face angle AG22 is in the range of 0 degrees to 60 degrees. In this embodiment, the first internal spline face angle AG21 is 5 degrees. The second internal spline face angle AG22 is 45 degrees. However, the first internal spline face angle AG21 and the second internal spline face angle AG22 are not limited to this embodiment and the above ranges.

[0106] As in Fig. As seen in Figure 30, the internal spline teeth 64 mesh with the external spline teeth 40 to transmit the rotational drive force F1 from the sprocket SP1 to the sprocket support body 28. The internal spline drive surface 66 can be brought into contact with the spline drive surface 48 to transmit the rotational drive force F1 from the sprocket SP1 to the sprocket support body 28. The internal spline non-drive surface 68 is spaced from the external spline non-drive surface 50 in a state where the internal spline drive surface 66 is in contact with the external spline drive surface 48.

[0107] As in Fig. 31, the sprocket SP2 has a plurality of internal splines 70. The sprocket SP3 has a plurality of internal splines 72. The sprocket SP4 has a plurality of internal splines 74. The first ring 59A has a plurality of internal splines 76. As shown in Fig.32, the hub engaging portion 60 of the sprocket retainer 56 includes a plurality of internal spline teeth 78. The plurality of internal spline teeth 70 have substantially the same structure as the plurality of internal spline teeth 64. The plurality of internal spline teeth 72 have substantially the same structure as the plurality of internal spline teeth 64. The plurality of internal spline teeth 74 have substantially the same structure as the plurality of internal spline teeth 64. The plurality of internal spline teeth 76 have substantially the same structure as the plurality of internal spline teeth 64. The plurality of internal spline teeth 78 have substantially the same structure as the internal internal spline teeth 64. Therefore, they will not be described in detail here for the sake of brevity.

[0108] The term "comprising" and its derivatives, as used herein, are to be understood as open-ended terms that specify the presence of the stated features, elements, components, groups, integers, and / or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers, and / or steps. This concept also applies to words with similar meanings, such as the terms "having," "including," and their derivatives.

[0109] The terms “member”, “section”, “portion”, “part”, “element”, “body” and “structure”, when used in the singular, can have the dual meaning of a single part or of multiple parts.

[0110] The ordinal numbers such as "first" and "second" as used in the present application are merely identifiers and have no other meaning, such as a specific order or the like. Furthermore, for example, the term "first element" itself does not imply the existence of a "second element," and the term "second element" itself does not imply the existence of a "first element."

[0111] The term “pair of” as used herein may include the configuration in which the pair of elements have different shapes or structures from each other in addition to the configuration in which the pair of elements have the same shapes or structures.

[0112] The terms “a” (or “an”), “one or more” and “at least one” may be used interchangeably herein.

[0113] Finally, the extent terms such as "substantially," "by," and "approximately," as used herein, mean a reasonable amount of variation from the modified term such that the final result is not significantly altered. All numerical values ​​described in this application can be interpreted to include "substantially," "by," and "approximately."

[0114] Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.

Claims

[1] A bicycle hub assembly (12) comprising: a sprocket support body (28) having at least ten external spline teeth (40) configured to engage a rear bicycle sprocket assembly (14), each of the at least ten external spline teeth (40) having an external spline drive surface (48) and an external spline non-drive surface (50), each of the at least ten external spline teeth (40) having the external spline drive surface (48) to receive a driving rotational force from the rear bicycle sprocket assembly (14) upon pedaling, the plurality of external spline drive surfaces (48) each comprising a radially outermost edge (48A), a radially innermost edge (48B), and a radial length (RL11) defined from the radially outermost edge (48A) to the radially innermost edge (48B), and a total sum of the radial lengths (RL11) of the external spline drive surfaces (48) is equal to or greater than 7 mm; and at least one external spline drive surface (48) of the at least ten external spline drive surfaces (48) having a first external spline surface angle (AG11) defined between the at least one external spline drive surface (48) and a first radial line (L11) extending from a rotational center axis (A1) of the bicycle hub assembly (12) to the radially outermost edge (48A) of the at least one external spline drive surface (48), the first external spline surface angle (AG11) being in the range of 0 degrees to 10 degrees. [2] Bicycle hub assembly (12) according to claim 1, wherein a total number of the at least ten external splines (40) is equal to or greater than 20, preferably equal to or greater than 25. [3] The bicycle hub assembly (12) of claim 1 or 2, wherein the at least ten external splines (40) have a first outer pitch angle (PA11) and a second outer pitch angle (PA12) different from the first outer pitch angle (PA11). [4] The bicycle hub assembly (12) of any one of claims 1 to 3, wherein at least one of the at least ten external splines (40) has a first spline shape that is different from a second spline shape of another of the at least ten external splines (40). [5] The bicycle hub assembly (12) of any one of claims 1 to 4, wherein at least one of the at least ten external splines (40) has a first spline size that is different from a second spline size of another of the at least ten external splines (40). [6] Bicycle hub assembly (12) according to one of claims 1 to 5, wherein the at least ten external splines (40) each have maximum circumferential widths (MW1) and the total sum of the maximum circumferential widths (MW1) is equal to or greater than 55 mm, preferably equal to or greater than 60 mm, preferably equal to or greater than 65 mm. [7] A bicycle hub assembly (12) comprising: A sprocket support body (28) having a plurality of external spline teeth (40) configured to engage a rear bicycle sprocket assembly (14), wherein at least two external spline teeth (40) of the plurality of external spline teeth (40) are circumferentially arranged at a first helix angle with respect to a rotational center axis of the bicycle hub assembly (14), wherein the first external helix angle ranges from 10 degrees to 20 degrees, wherein each of the plurality of external spline teeth (40) has an external spline drive surface (48) and an external spline non-drive surface, wherein each of the plurality of external spline teeth (40) has the external spline drive surface (48) for receiving a driving rotational force from the rear bicycle sprocket assembly (14) upon pedaling, wherein the plurality of external spline drive surfaces (48) each have a radially outermost edge (48A), a radially innermost edge (48B) and a radial length (RL11),which is defined from the radially outermost edge (48A) to the radially innermost edge (48B), and wherein a total sum of the radial lengths (RL11) of the external spline drive surfaces (48) is equal to or greater than 7 mm., [8] The bicycle hub assembly (12) of claim 7, wherein the first outer pitch angle ranges from 12 degrees to 15 degrees. [9] Bicycle hub assembly (12) according to claim 7 or 8, wherein at least two external spline teeth (40) of the plurality of external spline teeth (40) are arranged circumferentially at a second outer pitch angle with respect to the rotational center axis of the bicycle hub assembly, and the second outer pitch angle differs from the first outer pitch angle.

Images