TWM605183U - Rear sprocket wheel of manpower-driven vehicle - Google Patents

Abstract

[Question] To provide a lightweight rear sprocket for human-powered vehicles. [Solution] The rear sprocket for a human-powered vehicle is provided with: a titanium sprocket base with a rotation center axis; and from the outer periphery of the sprocket base toward a radial direction related to the rotation center axis For the plural number of sprocket teeth made of titanium extending outside, the total number of the aforementioned plural number of sprocket teeth is 16 or less, and the maximum outer diameter is 66mm or less.

Description

Rear sprocket for human drive vehicle

This model relates to a rear sprocket for a human-powered vehicle.

From the previous, the rear sprocket system for human-powered vehicles has been well known.

[Problems to be solved by the new model]

One of the objectives of the present invention is to provide a lightweight rear sprocket for human-powered vehicles. [Means to solve the problem]

The rear sprocket for a human-powered vehicle that follows the first side of the present invention is provided with: a titanium sprocket base with a rotation center axis; and from the outer periphery of the sprocket base and connected to the center of rotation The number of titanium sprocket teeth extending outward in the radial direction of the shaft, the total number of the aforementioned plural sprocket teeth, is 16 or less, and the maximum outer diameter is 66mm or less. If the rear sprocket for a human-powered vehicle is based on the first side surface, the sprocket base and the plural sprocket teeth are made of titanium, so the total number of the plural sprocket teeth can be 16 or less and the maximum outer diameter is Lightweight rear sprocket for human-powered vehicles under 66mm.

In the rear sprocket for a human-powered vehicle following the second side of the first side surface, the inner periphery of the sprocket base is provided with a torque that transmits torque to the human-powered vehicle hub assembly Conduction structure. If the rear sprocket for a human-powered vehicle according to the second side surface is described, the torque transmission structure can appropriately transmit torque to the human-powered vehicle hub assembly.

In the rear sprocket for a human-powered vehicle that follows the third side of the first or second side, the torque transmission structure includes a plurality of bolt grooves. According to the rear sprocket for a human-powered vehicle according to the third side surface, it is possible to appropriately transmit torque to the hub assembly for a human-powered vehicle by means of a plurality of bolt grooves.

In the rear sprocket for a human-powered vehicle following the fourth side of the third side, the plurality of bolt grooves include: a first bolt groove; and a second bolt groove, which are connected to the rotation center axis In the circumferential direction of the heart, there is no intervening bolt groove between itself and the first bolt groove but adjacent to the first bolt groove; and the third bolt groove is tied in the circumferential direction, and is connected to itself and The second bolt groove is adjacent to the second bolt groove without intervening other bolt grooves; and the fourth bolt groove is tied in the circumferential direction and is not between itself and the third bolt groove. There are other bolt grooves interposed and adjacent to the third bolt groove, and the first pitch angle between the driving surface of the first bolt groove and the driving surface of the second bolt groove defined in the circumferential direction, Is different from the second pitch angle between the driving surface of the second groove and the driving surface of the third groove defined in the circumferential direction. The first pitch angle is the same as that defined in the circumferential direction. The third pitch angle between the driving surface of the third groove and the driving surface of the fourth groove defined in the direction is equal. According to the rear sprocket for a human-powered vehicle on the fourth side, the first pitch angle and the second pitch angle system are different, and the first pitch angle and the third pitch angle system are equal. Therefore, it is for a human-powered vehicle hub assembly with a key groove corresponding to the first and third pitch angles, and a human-powered vehicle with a key groove corresponding to the second pitch angle Both sides of the vehicle hub assembly can be installed.

In the rear sprocket for a human-powered vehicle that follows the fifth side of the fourth side, the plurality of bolt grooves include: the fifth bolt groove is connected in the circumferential direction of the rotation center axis, There is no other bolt groove intervening between itself and the aforementioned fourth bolt groove, but is adjacent to the aforementioned fourth bolt groove; and the sixth bolt groove is tied in the aforementioned circumferential direction between itself and the aforementioned fifth bolt groove. There is no intervening bolt groove but adjacent to the fifth bolt groove. The second pitch angle is related to the driving surface of the fourth bolt groove and the fifth bolt groove defined in the circumferential direction. The fourth pitch angle between the driving surfaces is equal, and the first pitch angle and the third pitch angle are related to the driving surface and the sixth bolt of the fifth slot defined in the circumferential direction. The fifth pitch angle between the driving surfaces of the grooves is equal. According to the rear sprocket for a human-powered vehicle on the fifth side, the second pitch angle is equal to the fourth pitch angle, and the first and third pitch angles are equal to the fifth pitch angle. equal. Therefore, regardless of whether it is a human-powered vehicle hub assembly with a spline groove corresponding to the first pitch angle, the third pitch angle, and the fourth pitch angle, or the hub assembly with the second pitch angle and Any of the wheel hub assemblies for human-powered vehicles with bolt grooves corresponding to the 4th pitch angle can transmit torque through plural driving surfaces.

The rear sprocket for a human-powered vehicle on the sixth side that follows any one of the first to fifth side surfaces is equipped with an inward shifting promotion structure that promotes the chain for a human-powered vehicle from being connected to the aforementioned There is no other sprocket interposed in the axis direction of the central axis of rotation, but the small sprocket adjacent to the rear sprocket for the human-powered vehicle moves toward the rear sprocket for the human-powered vehicle. According to the rear sprocket for human-powered vehicles on the sixth side, the chain for human-powered vehicles can move smoothly from the small sprocket adjacent to the rear sprocket for human-powered vehicles by the inward shifting promotion structure. Rear sprocket for human-powered vehicles.

The rear sprocket for human-powered vehicles on the seventh side, which follows any one of the first to sixth sides mentioned above, is equipped with: an outward shifting promotion structure, which promotes the chain for human-powered vehicles from being used for human-powered vehicles. The rear sprocket moves toward a speed change operation in which a small sprocket that is adjacent to the rear sprocket for a human-powered vehicle moves in the direction of the axis related to the aforementioned rotation center axis without intervening other sprocket. According to the rear sprocket for human-powered vehicles on the seventh side, the chain system for human-powered vehicles can smoothly move from the rear sprocket for human-powered vehicles to the rear sprocket for human-powered vehicles through the outward shifting promotion structure. The adjacent small sprocket moves. [New type effect]

The new rear sprocket for a human-powered vehicle can be lightweight.

<Implementation form>

The rear sprocket 30 for a human-powered vehicle of the embodiment will be described with reference to FIGS. 1 to 13. A human-powered vehicle is a vehicle that has at least one wheel and can at least be driven by human power. Human-powered bicycles include, for example, various types of bicycles including mountain bikes, road bicycles, city bicycles, cargo bicycles, hand bicycles, kick scooters, and the like. The number of wheels of a human-powered vehicle is not limited. Human-powered vehicles, for example, also include 1-wheel vehicles and vehicles with more than three wheels. Human-powered vehicles are not limited to vehicles that can be driven by human power alone. Human-powered bicycles are not only driven by human power, but also include electric bicycles (E-bike) that use the driving power of an electric motor for propulsion. Electric bicycles include electric assisted bicycles that are assisted in propulsion by an electric motor. Hereinafter, in the embodiment, a human-powered vehicle is described as a bicycle.

The sprocket assembly 10 for a human-powered vehicle shown in FIG. 1 is installed at the rear wheel of the human-powered vehicle. The sprocket assembly 10 for a human-powered vehicle includes a plurality of rear sprockets 12 and is installed at the hub assembly 20 for a human-powered vehicle. After the plural number of sprockets 12, at least one rear sprocket 30 for a human-powered vehicle is included.

The rear sprocket 30 for a human-powered vehicle shown in FIGS. 2 and 3 is provided with: a sprocket base 32 made of titanium with a rotation center axis C1; and a sprocket base 32 from the outer periphery 32A of the sprocket base 32 Plural sprocket teeth 34 made of titanium extending toward the outer side X1 in the radial direction connected to the rotation center axis C1. The total number of plural sprocket teeth 34 is 16 or less, and the maximum outer diameter L1 is 66mm or less. Preferably, the total number of the plural sprocket teeth 34 is 9 or more. Ideally, the maximum outer diameter L1 is 30mm or more.

The total number of the plural sprocket teeth 34 in the sprocket 12 contained in the sprocket assembly 10 for a human-powered vehicle is 16 or less, and the maximum outer diameter L1 is 66mm or less. All of the sprocket 12 can be This is a rear sprocket 30 for a new type of human-powered vehicle. The total number of the plural sprocket teeth 34 in the sprocket 12 included in the sprocket assembly 10 for human-powered vehicles is 16 or less, and the maximum outer diameter L1 is 66mm or less. The sprocket 12 may be only part of it. After that, the sprocket 12 is a rear sprocket 30 for a human-powered vehicle of the new type.

Preferably, the inner peripheral edge 32B of the sprocket base 32 is provided with a torque transmission structure 36 that transmits torque to the human-powered vehicle hub assembly 20. The torque transmission structure 36 includes a plurality of bolt grooves 38. Preferably, the plurality of bolt grooves 38 include a first bolt groove 40, a second bolt groove 42, a third bolt groove 44, and a fourth bolt groove 46. The second bolt groove 42 is located in the circumferential direction R related to the rotation center axis C1 and is adjacent to the first bolt groove 40 without interposing another bolt groove 38 between itself and the first bolt groove 40. The third bolt groove 44 is in the circumferential direction R, and is adjacent to the second bolt groove 42 without interposing another bolt groove 38 between itself and the second bolt groove 42. The fourth bolt groove 46 is in the circumferential direction R, and is adjacent to the third bolt groove 44 without interposing another bolt groove 38 between itself and the third bolt groove 44. The first pitch angle D1 between the driving surface 40A of the first groove 40 and the driving surface 42A of the second groove 42 defined in the circumferential direction R is the same as the first pitch angle D1 defined in the circumferential direction R The second pitch angle D2 between the driving surface 42A of the second bolt groove 42 and the driving surface 44A of the third bolt groove 44 is different. The first pitch angle D1 is equal to the third pitch angle D3 between the driving surface 44A of the third groove 44 and the driving surface 46A of the fourth groove 46 defined in the circumferential direction R.

Preferably, the plurality of bolt grooves 38 includes a fifth bolt groove 48 and a sixth bolt groove 50. The fifth bolt groove 48 is located in the circumferential direction R related to the rotation center axis C1 and is adjacent to the fourth bolt groove 46 without interposing another bolt groove 38 between itself and the fourth bolt groove 46. The sixth bolt groove 50 is in the circumferential direction R, and is adjacent to the fifth bolt groove 48 without interposing another bolt groove 38 between itself and the fifth bolt groove 48. The second pitch angle D2 is equal to the fourth pitch angle D4 between the driving surface 46A of the fourth bolt groove 46 and the driving surface 48A of the fifth bolt groove 48 defined in the circumferential direction R. The first pitch angle D1 and the third pitch angle D3 are the fifth section between the driving surface 48A of the fifth groove 48 and the driving surface 50A of the sixth groove 50 defined in the circumferential direction R The distance angle D5 is equal. In this embodiment, the first pitch angle D1, the third pitch angle D3, and the fifth pitch angle D5 are smaller than the second pitch angle D2 and the fourth pitch angle D4.

Each of the plurality of bolt grooves 38 is each of the plurality of convex portions provided at the inner peripheral edge 32B. In this embodiment, the plural number of bolt grooves 38 are even numbers. The number of the plurality of bolt grooves 38 is 18, for example. The plurality of bolt grooves 38 may also include positioning bolt grooves 52. The positioning bolt groove 52 may be one of the first bolt groove 40, the second bolt groove 42, the third bolt groove 44, the fourth bolt groove 46, the fifth bolt groove 48, and the sixth bolt groove 50. The positioning bolt groove 52 is, for example, a bolt groove 38 whose length in the circumferential direction R is greater than that of other bolt grooves 38. In the configuration in which the rear sprocket 30 for the human-powered vehicle is installed at the hub assembly 20 for the human-powered vehicle, the rear sprocket 30 for the human-powered vehicle is assembled with respect to the hub assembly for the human-powered vehicle by the positioning bolt groove 52 The phase of the body 20 in the circumferential direction R is positioned.

The plurality of bolt grooves 38 make the pitch angle D between the driving surfaces of the two adjacent bolt grooves 38 so that the pitch angle DX and the pitch angle DY are relative to each other in the circumferential direction R It is arranged at the inner periphery 32B in an interactive manner. The pitch angle DX is equal to the first pitch angle D1, the third pitch angle D3, and the fifth pitch angle D5. The pitch angle DY is equal to the second pitch angle D2 and the fourth pitch angle D4. In this embodiment, the pitch angle DX is smaller than the pitch angle DY.

As shown in FIGS. 4 and 5, the rear sprocket 30 for a human-powered vehicle is configured to be able to be attached to a different hub assembly 20 for a human-powered vehicle. The first human-powered vehicle hub assembly 20A shown in FIG. 4 includes a plurality of bolt grooves 22. The number of the plurality of bolt grooves 22 is less than the number of the plurality of bolt grooves 38. There are 9 peg grooves 22 in FIG. 4. One bolt groove 22 has a size that can be engaged with two bolt grooves 38. The first human-powered vehicle hub assembly 20A is secured at a portion 23 between two adjacent bolt grooves 22, and is provided with a recess 23A that is recessed from the outer periphery of the hub assembly 20 toward the inside. With the recess 23A, the weight reduction of the hub assembly 20 is achieved. Preferably, the plurality of bolt grooves 22 include positioning grooves 24. The positioning groove 24 has a size capable of engaging with the positioning bolt groove 52. The length of the positioning groove 24 in the circumferential direction R is different from that of other bolt groove grooves 22. Preferably, the positioning groove 24 is provided with a positioning bolt groove 52 and one of the other bolt grooves 38.

The second hub assembly 20B for a human-powered vehicle shown in FIG. 5 includes a plurality of bolt grooves 26. The number of the plurality of bolt grooves 26 is equal to the number of the plurality of bolt grooves 38. There are 18 bolt grooves 26 in Figure 5. The plurality of spline grooves 26 includes a plurality of first spline grooves 26A and one positioning groove 26B. The first bolt groove 26A is provided with the first bolt groove 40, the second bolt groove 42, the third bolt groove 44, the fourth bolt groove 46, the fifth bolt groove 48, or the sixth bolt groove 50. Fit the size. The positioning groove 26B has a size capable of engaging with the positioning bolt groove 52. At the plurality of first bolt grooves 26A, the first bolt groove 40, the second bolt groove 42, the third bolt groove 44, the fourth bolt groove 46, the fifth bolt groove 48, or the sixth bolt are respectively arranged The groove 50 is provided with a positioning bolt groove 52 at the positioning groove 26B. The part 27 between the second bolt groove 42 and the third bolt groove 44 among the part 27 between the two adjacent first bolt grooves 26A, and the fourth bolt groove 46 and the fifth bolt groove 48 In the middle portion 27, a first convex portion 27A and a second convex portion 27B are provided. The first protrusion 27A is in contact with the driving surface of the bolt groove 38. The second convex portion 27B has a smaller protrusion height toward the radially outer side of the second human-powered vehicle hub assembly 20B than the first convex portion 27A. The second convex portion 27B is located in the circumferential direction R and faces the non-driving surface on the opposite side to the driving surface of the key groove 38. The second convex portion 27B may be in contact with the non-driving surface on the opposite side to the driving surface of the bolt groove 38 in the circumferential direction R.

As shown in FIGS. 6 and 7, the shapes of the grooves 38 can also be different. For example, the shape of the bolt groove 39X corresponding to the first bolt groove 40, the third bolt groove 44, and the fifth bolt groove 48 among the plurality of bolt grooves 38, and the shape of the second bolt groove 42 and the fourth bolt groove 46 And the shape of the bolt groove 39Y corresponding to the sixth bolt groove 50 may be different. The upright portion of the key groove 39X from the inner peripheral edge 32B on the driving surface side is provided with the first R corner portion 39A. Among the bolt grooves 39X, the "upright portion from the inner peripheral edge 32B on the non-driving surface side opposite to the driving surface in the circumferential direction R" is provided with a second R corner portion 39B. The vertical portion of the key groove 39Y from the inner peripheral edge 32B on the driving surface side is provided with a third R corner portion 39C. Among the key grooves 39Y, the "upright portion from the inner peripheral edge 32B on the non-driving surface side opposite to the driving surface in the circumferential direction R" is provided with a 4th R corner portion 39D. The curvature radius of one of the first R corner portion 39A, the second R corner portion 39B, the 3R corner portion 39C, and the 4R corner portion may be different from the curvature radius of at least one of the other corner portions.

In the present invention, the radius of curvature r3 of the third R corner 39C is, for example, 0.3. In the present invention, the radius of curvature r1 of the first R corner portion 39A is larger than the radius of curvature r3 of the third R corner portion 39C. In the present invention, the radius of curvature r1 of the first R corner 39A is, for example, 0.5. In the present invention, the radius of curvature r2 of the second R corner portion 39B is larger than the radius of curvature r3 of the third R corner portion 39C. In the present invention, the radius of curvature r2 of the second R corner portion 39B is larger than the radius of curvature r1 of the first R corner portion 39A. In this invention, the curvature radius r2 of the 2nd R corner part 39B is 1.0, for example. In the present invention, the radius of curvature r4 of the 4th R corner 39D is larger than the radius of curvature r3 of the 3rd R corner 39C. In the present invention, the radius of curvature r4 of the fourth R corner portion 39D is equal to the radius of curvature r1 of the first R corner portion 39A. In the present invention, the radius of curvature r4 of the 4th R corner 39D is, for example, 0.5. In the present invention, each radius of curvature has a relationship of r2>r4=r1>r3. Each radius of curvature may have a relationship other than r2>r4=r1>r3.

Since the radius of curvature r3 of the third R corner 39C is the smallest, for example, as shown in FIG. 7, the driving surface of the groove 39Y and the first groove can be connected with respect to the second human-powered vehicle hub assembly 20B. The contact area between the driving surfaces of the groove 26A is increased.

Since the radius of curvature r1 of the first R corner portion 39A is larger than the radius of curvature r3 of the third R corner portion 39C, it is possible to set the area of the bolt groove 39X in the shearing direction to be larger than that of the bolt groove 39Y. Big. Therefore, it is possible to increase the strength of the bolt groove 39X for engagement with the driving surface of the bolt groove 22 of the first human-powered vehicle hub assembly 20A as shown in FIG. 6. Since the radius of curvature r1 of the first R corner portion 39A is smaller than the radius of curvature r2 of the second R corner portion 39B, for example, as shown in FIG. 6, the bolt groove 39X and the first sprocket 12 1 Interference between the bolt grooves of the wheel hub assembly 20A for human-powered vehicles is suppressed.

Since the radius of curvature r2 of the second R corner portion 39B is larger than the radius of curvature r3 of the third R corner portion 39C, it is possible to set the area of the bolt groove 39X in the shearing direction to be larger than that of the bolt groove 39Y. Big. Therefore, it is possible to increase the strength of the bolt groove 39X for engagement with the driving surface of the bolt groove 22 of the first human-powered vehicle hub assembly 20A as shown in FIG. 6.

The radius of curvature r4 of the 4th R corner portion 39D is larger than the radius of curvature r3 of the 3rd R corner portion 39C. Therefore, the area in the shearing direction of the bolt groove 39X can be set larger than that of the bolt groove 39Y. Big. Therefore, it is possible to increase the strength of the bolt groove 39Y for engagement with the driving surface of the bolt groove 22 of the first human-powered vehicle hub assembly 20A as shown in FIG. 6.

As shown in FIGS. 2 and 3, it is preferable that the rear sprocket 30 for a human-powered vehicle is provided with an inward speed change promotion structure 54. The inward shifting promotion structure 54 promotes the chain for the human-powered vehicle from being adjacent to the rear sprocket 30 for the human-powered vehicle in the axial direction Y connected to the central axis of rotation C1 without intervening the other sprocket 12 The small sprocket moves toward the rear sprocket 30 for a human-powered vehicle for a speed change operation. The inward speed change promotion structure 54 is used to move the chain for a human-powered vehicle from a small sprocket adjacent to the rear sprocket 30 for a human-powered vehicle toward the rear sprocket 30 for a human-powered vehicle by a rear speed changer. In this case, the chain for the human-powered vehicle is engaged with the sprocket 34 of the rear sprocket 30 for the human-powered vehicle, and is arranged in a part of the plurality of sprocket teeth 34 and a part of the sprocket base 32 Place. Therefore, the inward shifting promotion structure 54 is designed to promote the inward shifting operation of the chain for the human-powered vehicle from the small sprocket adjacent to the rear sprocket 30 for the human-powered vehicle to the rear sprocket 30 for the human-powered vehicle. The way and intentionally made the design structure. The inward speed change promotion mechanism 54 includes, for example, at least one inward speed change promotion tooth 54B formed with a recess 54A provided on the surface of the rear sprocket 12 opposite to the small sprocket, and related to the human drive The driving rotation direction R1 of the rear sprocket 30 for a vehicle is arranged at least one inward gearshift tooth 54C on the upstream side of the inward gearshift promotion tooth 54B. In the inward shifting operation, if the chain for a human-powered vehicle, which has been separated from the small sprocket adjacent to the rear sprocket 30 for a human-powered vehicle, comes into contact with the concave portion 54A of the inward shift accelerating tooth 54B, the concave portion 54A The step portion is guided by the chain for the human-powered vehicle by engaging with the inward gear shifting acceleration tooth 54B of the rear sprocket 30 for the human-powered vehicle.

Preferably, the rear sprocket 30 for a human-powered vehicle is provided with an outward shifting acceleration structure 56. The outward shifting promotion structure 56 promotes the chain for the human-powered vehicle to move from the rear sprocket 30 for the human-powered vehicle toward the axis direction Y related to the rotation center axis C1 without intervening the other sprocket 12 but with the human power A speed change action for driving the small sprocket adjacent to the rear sprocket 30 for the vehicle to move. The outward speed change promotion structure 56 is used to move the chain for a human-powered vehicle from the rear sprocket 30 for a human-powered vehicle to a small sprocket adjacent to the rear sprocket 30 for a human-powered vehicle by a rear speed changer. In this case, the chain for the human-powered vehicle is detached from the sprocket 34 of the rear sprocket 30 for the human-powered vehicle, and is set at a part of the plurality of sprocket teeth 34. Therefore, the outward shifting promotion structure 56 is designed to promote the outward shifting action of the chain for the human-powered vehicle from the rear sprocket 30 for the human-powered vehicle to the small sprocket adjacent to the rear sprocket 30 for the human-powered vehicle. The way and intentionally made the design structure. The outward speed change promotion mechanism 56 includes, for example, at least one outward speed change tooth 56B formed with a recessed portion 56A provided on the surface of the rear sprocket 12 opposite to the small sprocket, and connected to a human-powered vehicle At least one outward speed change accelerating tooth 56C is arranged on the downstream side of the outward speed change tooth 56B in the driving rotation direction R1 of the rear sprocket 30. In the outward shifting operation, the outward shifting acceleration tooth 56C is provided with the chain for the human-powered vehicle when the chain for the human-powered vehicle is engaged with the outward shifting acceleration tooth 56C to make the chain for the human-powered vehicle face the rear sprocket 30 The shape of the adjacent small sprocket side displacement is general. In the state where the chain for the human-powered vehicle is engaged with the outward shifting acceleration tooth 56C, the chain for the human-powered vehicle is driven from the rear sprocket for the human-powered vehicle by the presence of the recess 56A formed at the outward shifting tooth 56B The outer gear shifting tooth 56B is disengaged from the outer side 30 and moves toward the small sprocket adjacent to the rear sprocket 30 for the human-powered vehicle, and the outer gear shifting operation system ends. The plurality of outer gears 56B may also be provided at the rear sprocket 30 for a human-powered vehicle. The plurality of outer gear shifting acceleration teeth 56C may also be provided at the rear sprocket 30 for a human-powered vehicle.

Preferably, the inward speed change promotion structure 54 and the outward speed change promotion structure 56 are provided at different sprocket teeth 34 among the plurality of sprocket teeth 34. Alternatively, the inward speed change promotion structure 54 and the outward speed change promotion structure 56 may be partially overlapped in the circumferential direction related to the rotation center axis C1 of the rear sprocket 30 for the human-powered vehicle. When the rear sprocket 30 for a human-powered vehicle is the smallest sprocket 12 of the rear sprocket 12 assembled at the hub assembly 20 for a human-powered vehicle, it is ideal. 30. The system does not have any one of the inward shifting promotion structure 54 and the outward shifting promotion structure 56.

The sprocket support member 28 attached to the hub assembly 20 for a human-powered vehicle will be described with reference to FIGS. 8 to 12. In this embodiment, the sprocket support member 28 connects two adjacent rear sprockets 12 at the sprocket assembly 10 for a human-powered vehicle. The sprocket support member 28 can also support more than three rear sprockets 12.

Each of the two rear sprockets 12 connected by the sprocket support member 28 is provided with an annular base 12A and a plurality of chains extending from the outer periphery of the base 12A toward the outside in the radial direction Gear teeth 12B.

The sprocket support member 28 contains, for example, a resin material. The sprocket supporting member 28 may also include metal materials. The sprocket support member 28 is provided with a cylindrical portion 28A arranged at the inner periphery of the two rear sprockets 12, and a cylindrical portion 28A extending from the outer periphery of the cylindrical portion 28A toward the radially outer side and is connected to the rotation The protrusion 28B between the two rear sprockets 12 in the axial direction Y of the central axis C1 is arranged.

As shown in FIG. 8, the protrusion 28B is provided with a plurality of protrusions 28B. In this embodiment, the number of protrusions 28B is six. A mounting portion 28C is provided at each of the plural protruding portions 28B.

As shown in FIG. 9, the thickness H1 of the mounting portion 28C is greater than the thickness H2 of the portion of the protruding portion 28B outside the mounting portion 28C. The difference between the thickness H1 and the thickness H2 is, for example, 0.1 mm. The thickness H2 is, for example, 1.5 mm or more and 2.5 mm or less.

As shown in FIG. 10, the mounting portion 28C has a circular shape when viewed from the axial direction Y of the sprocket 12. Preferably, the mounting portion 28C has a substantially elliptical shape when viewed from the axis direction Y of the sprocket 12. The mounting portion 28C, for example, the direction along the radial direction of the sprocket support member 28 is the short axis 28X, and the direction orthogonal to the short axis 28X is the long axis 28Y. A hole 28D is provided at the mounting portion 28C. When viewed from the axis direction Y of the sprocket 12, the center point A1 of the mounting portion 28C and the center point A2 of the hole 28D are different. The center point A2 of the hole 28D, for example, is attached to the short axis 28X, and is arranged on the inner side of the center point A1 of the mounting portion 28C in the radial direction. By setting the mounting portion 28C in such a shape, the strength of the mounting portion 28C can be improved without excessively increasing the weight.

As shown in FIG. 8, at the hole 28D, for example, a rivet 28E is provided. The rivet 28E penetrates each of the holes 12C and the holes 28D provided at the base 12A of the two sprockets 12 connected by the sprocket support member 28. With the rivet 28E, the two sprockets 12 are installed at the sprocket support member 28.

As shown in FIG. 9, a plurality of bolt grooves 28F are provided at the inner periphery of the sprocket supporting member 28. Preferably, the plurality of bolt grooves 28F have the same structure as the plurality of bolt grooves 38 of the rear sprocket 30 for human-powered vehicles.

Since the mounting portion 28C has an elliptical shape, for example, the area and volume of the mounting portion 28C can be increased compared to the case where it is formed in a circular shape with a diameter equal to the minor axis 28X. Therefore, the strength of the mounting portion 28C can be improved.

The manufacturing method of the plural sprocket 12 will be described with reference to FIGS. 12 and 13. Fig. 12 and Fig. 13 respectively show an example of the method of manufacturing the plural rear sprocket 12 of different types.

At least one of the plurality of sprockets 12 may be a rear sprocket 30 for a human-powered vehicle, or a rear sprocket 12 different from the rear sprocket 30 for a human-powered vehicle. Preferably, the plural number of sprockets are used in the same type of sprocket assembly 10 for human-powered vehicles. After the plural number of sprockets 12 are used, for example, one sprocket assembly 10 for a human-powered vehicle or the same type of sprocket assembly 10 for a human-powered vehicle are used.

The manufacturing method of the sprocket 12 after the plural number is, for example, a process including the stamping process of the sheet metal 70. The sheet metal 70 contains a titanium alloy. In the process of pressing the sheet metal 70, the sprocket material 60 of each of the sprocket wheels 12 after the plural number is obtained from one sheet metal 70. Therefore, the yield rate due to the manufacturing method of the sprocket 12 after the plural number is improved.

The plural sprocket 12 includes, for example, a first sprocket 62 and a second sprocket 64 having a smaller number of teeth and an outer diameter than the first sprocket 62. Preferably, the maximum outer diameter of the second sprocket 64 is less than 80 mm in diameter. Preferably, the maximum outer diameter of the second sprocket 64 is 30 mm or more in diameter. Preferably, the maximum outer diameter of the first sprocket 62 is 250 mm or less in diameter. Preferably, the maximum outer diameter of the first sprocket 62 is 65 mm or more in diameter.

In the process of press processing of the sheet metal 70, the material corresponding to the second sprocket 64 is arranged at the inner periphery of the material corresponding to the first sprocket 62. Preferably, in the sheet metal 70, the material corresponding to the first sprocket 62 and the material corresponding to the second sprocket 64 are such that the rotation center axis C2 of the first sprocket 62 and the second sprocket 64 The rotation center axes C3 are taken out from the sheet metal 70 so that they coincide with each other.

The number of the sprocket material 60 of the plural sprocket 12 formed by the stamping process of the sheet metal 70 may be 3 or more.

The sprocket material 60 of each of the plural rear sprocket wheels for human-powered vehicles can be taken out at the same time, or can be configured to be taken out sequentially. Preferably, after the sprocket material 60 of each is taken out from the sheet metal 70, it is processed by cutting or the like, and the rear sprocket 12 is formed.

<Modifications> The description related to the embodiment is an example of the form that the rear sprocket for a human-powered vehicle can take according to the present disclosure, and does not represent a restriction on its form. The rear sprocket for a human-powered vehicle according to the present disclosure can take, for example, a modified example of the embodiment shown below and a combination of at least two modified examples that are not inconsistent with each other. In the following modification examples, the same reference numerals as in the embodiment are attached to the parts that are common to the embodiment, and the description is omitted.

・The plurality of bolt grooves 38 of the rear sprocket 30 for human-powered vehicles can also be configured as one of the first human-powered vehicle hub assembly 20A and the second human-powered vehicle hub assembly 20B The grooves 22 and 26 are arranged at the inner peripheral edge 32B in a manner corresponding to the shapes.

・The sprocket assembly 10 for a human-powered vehicle may not have the sprocket support member 28. In this case, for example, a torque transmission structure 36 or a torque transmission structure similar to the torque transmission structure 36 is provided at the inner periphery of all the rear sprockets 12.

The expression of "at least one" used in this manual means "more than one" of the desired option. As an example, the expression of "at least one" used in this manual, if the number of options is two, it means "only one option" or "both of two options". As another example, the expression of "at least one" used in this manual, if the number of options is 3 or more, it means "only one option" or "two or more options". combination".

20: Wheel hub assembly for human drive vehicles 30: Rear sprocket for human drive vehicles 32: Sprocket base 32A: Outer periphery 32B: inner periphery 34: Sprocket 36: Torque transmission structure 38: bolt groove 40: No. 1 bolt groove 40A: Drive surface 42: 2nd bolt groove 42A: Drive surface 44: 3rd bolt groove 44A: Drive surface 46: No. 4 bolt groove 46A: Drive surface 48: No. 5 bolt groove 48A: Drive surface 50: 6th bolt groove 50A: Drive surface 54: Inward speed change promotion structure 56: Outward shifting promotion structure

Fig. 1 is a side view of a sprocket assembly for a human-powered vehicle including a rear sprocket for a human-powered vehicle of the embodiment. [Figure 2] is a front view of a rear sprocket for a human-powered vehicle of the embodiment. [Figure 3] is a rear view of the rear sprocket for a human-powered vehicle of the embodiment. Fig. 4 is a front view showing a state where the first human-powered vehicle hub assembly is attached to the rear sprocket for the human-powered vehicle of the embodiment. Fig. 5 is a front view showing a state where a second hub assembly for a human-powered vehicle is attached to a rear sprocket for a human-powered vehicle of the embodiment. [Fig. 6] is a front view showing an enlarged part of Fig. 4. [Fig. 7] is a front view showing an enlarged part of Fig. 5. [Fig. 8] is a cross-sectional view showing the two rear sprocket and sprocket support member of Fig. 1. [Figure 9] is a front view showing the sprocket support member of Figure 8. [Fig. 10] is a side view showing the peripheral structure of the convex portion of the sprocket support member of Fig. 9. [Figure 11] is a front view showing the peripheral structure of the convex portion of the sprocket support member of Figure 9; [Fig. 12] is a schematic diagram showing the first example of the manufacturing method of the rear sprocket for the human-powered vehicle in Fig. 1. [Fig. [Fig. 13] is a schematic diagram showing the second example of the manufacturing method of the rear sprocket for the human-powered vehicle of Fig. 1. [Fig.

12: Rear sprocket

30: Rear sprocket for human drive vehicles

32: Sprocket base

32A: Outer periphery

32B: inner periphery

34: Sprocket

36: Torque transmission structure

38: bolt groove

40: No. 1 bolt groove

40A: Drive surface

42: 2nd bolt groove

42A: Drive surface

44: 3rd bolt groove

44A: Drive surface

46: No. 4 bolt groove

46A: Drive surface

48: No. 5 bolt groove

48A: Drive surface

50: 6th bolt groove

50A: Drive surface

52: positioning bolt groove

54: Inward speed change promotion structure

54A: recess

54B: Inward shifting promotion gear

54C: Inward gear

56: Outward shifting promotion structure

56A: recess

56B: Outward gear

56C: Outward shifting promotion gear

C1: Rotation center axis

D: Pitch angle

D1: 1st pitch angle

D2: 2nd pitch angle

D3: 3rd pitch angle

D4: 4th pitch angle

D5: 5th pitch angle

DX: Pitch angle

DY: pitch angle

L1: Maximum outer diameter

R: circumferential direction

R1: Drive rotation direction

X1: radially outside

Claims (7)

A rear sprocket for a human-powered vehicle is provided with: a sprocket base made of titanium with a rotation center axis; and a sprocket base extending from the outer periphery of the sprocket base toward the outside in the radial direction related to the rotation center axis For titanium-made plural sprocket teeth, the total number of the aforementioned plural sprocket teeth is 16 or less, and the maximum outer diameter is 66mm or less. The rear sprocket for a human-powered vehicle according to claim 1, wherein the inner peripheral edge of the sprocket base is provided with a torque transmission structure that transmits torque to the human-powered vehicle hub assembly. The rear sprocket for a human-powered vehicle according to claim 2, wherein the torque transmission structure includes a plurality of bolt grooves. The rear sprocket for a human-powered vehicle according to claim 3, wherein the plurality of bolt grooves include: a first bolt groove; and a second bolt groove, which are connected in the circumferential direction of the rotation center axis Above, there is no other bolt groove intervening between itself and the first bolt groove, but is adjacent to the first bolt groove; and the third bolt groove is tied in the circumferential direction and is in contact with the second bolt The grooves do not intervene with other bolt grooves but are adjacent to the aforementioned second bolt groove; and the fourth bolt groove, which is tied in the aforementioned circumferential direction, between itself and the aforementioned third bolt groove It is adjacent to the third groove without intervening other grooves. The first groove between the driving surface of the first groove and the driving surface of the second groove defined in the circumferential direction The pitch angle is different from the second pitch angle between the driving surface of the second groove and the driving surface of the third groove defined in the circumferential direction. The first pitch angle is It is equal to the third pitch angle between the driving surface of the third groove and the driving surface of the fourth groove defined in the circumferential direction. The rear sprocket for a human-powered vehicle according to claim 4, wherein the plurality of bolt grooves include: a fifth bolt groove, which is connected in the circumferential direction of the rotation center axis, between itself and the aforementioned The fourth bolt groove is adjacent to the aforementioned fourth bolt groove without intervening other bolt grooves; and the sixth bolt groove is tied in the aforementioned circumferential direction and does not intervene between itself and the aforementioned fifth bolt groove There are other grooves adjacent to the fifth groove, and the second pitch angle is related to the driving surface of the fourth groove and the driving surface of the fifth groove defined in the circumferential direction. The fourth pitch angle is equal to each other, and the first pitch angle and the third pitch angle are defined in the circumferential direction of the driving surface of the fifth groove and the driving surface of the sixth groove. The fifth pitch angle between them is equal. The rear sprocket for a human-powered vehicle as described in claim 1 or 2, wherein: The inward shifting promotion structure promotes the chain for a human-powered vehicle from a small sprocket adjacent to the rear sprocket of the human-powered vehicle without intervening other sprocket in the direction of the axis connected to the aforementioned central axis of rotation. A shifting action that moves toward the rear sprocket for a human-powered vehicle. The rear sprocket for a human-powered vehicle according to claim 1 or 2, wherein the rear sprocket for a human-powered vehicle is provided with: an outward shifting promotion structure that facilitates the chain for the human-powered vehicle to move from the rear sprocket of the human-powered vehicle to the front A speed change action in which a small sprocket adjacent to the rear sprocket for a human-powered vehicle is moved without intervening other sprocket in the axis direction of the rotation center axis.

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