transmission sprocket

Abstract

A transmission sprocket comprising: a chainring body made of a first non-metallic material and having a plurality of teeth and at least one mounting hole on its radial outer circumference; a chain guard made of a second non-metallic material and covering one side of the chainring body and enclosing an interior space with the chainring body, the interior space surrounding the axis of the chainring body; and a climbing aid arranged in the at least one mounting hole of the chainring body; wherein a rib is provided in the interior of one of the two components - chainring body and chain guard disc - and extends radially from the axis in the direction of the climbing aid and rests against the other of the two components - chainring body and chain guard disc.

Description

Field of the invention

[0001] The present invention relates to a sprocket and, more particularly, to a transmission sprocket combined with the chain in a bicycle and used for power transmission. State of the art

[0002] Since the invention of the bicycle, there have been many changes in bicycle design and the development of gearshift mechanisms. Because the weight of the bicycle places an additional burden on the rider in terms of energy consumption, the question of how to reduce the weight of the bicycle without increasing the risk of damage to the gearshift mechanism has become an important issue in bicycles.

[0003] To reduce the weight of a bicycle, not only can the frame materials be modified, but the frame structure can also be optimized. However, due to different material properties, the original vehicle body structure may no longer be sufficiently strong after a change in the vehicle body material. Therefore, when adapting the frame to the changed material, the design of the gearshift mechanism should also be modified accordingly. Object of the invention

[0004] The present invention provides a transmission sprocket having the advantages of light weight and high structural strength.

[0005] To achieve the above-mentioned advantages, an embodiment of the present invention provides a transmission sprocket comprising: a chainring body made of a first non-metallic material and having a plurality of teeth and at least one mounting hole on its radial outer circumference; a chainguard disc made of a second non-metallic material and covering one side of the chainring body and enclosing an inner space with the chainring body, the inner space surrounding the axis of the chainring body; and a climbing aid arranged in the at least one mounting hole of the chainring body, wherein a rib is provided in the inner space on one of the two components - chainring body and chainguard disc - and extends radially from the axis towards the climbing aid and bears against the other of the two components - chainring body and chainguard disc.

[0006] In one embodiment, the chain guard disc has a second disc wall opposite the chainring body, the second disc wall extending obliquely from the side near the axis to the direction away from the axis and gradually approaching the chainring body.

[0007] In one embodiment, the second disc wall has a stepped structure and a plurality of first ring portions, each first ring portion extending obliquely from the side near the axis to the side far from the axis and gradually approaching the chainring body.

[0008] In one embodiment, the second disc wall further comprises a second ring section, wherein the second ring section is connected to two adjacent first ring sections and does not run parallel to the first ring sections.

[0009] In one embodiment, one of the first ring sections is located on the outer circumference of the chain guard disc.

[0010] In one embodiment, the outer circumference of the chain guard disc is provided with a gap, with the climbing aid being pushed through the gap.

[0011] In one embodiment, the ribs each extend from the chainring body and the chainguard disc and abut each other.

[0012] In one embodiment, the first non-metallic material and the second non-metallic material are the same material.

[0013] In one embodiment, the first non-metallic material and the second non-metallic material are different materials.

[0014] In one embodiment, the climbing aid is made of a non-metallic material.

[0015] As described above, in the transmission sprocket according to the invention, according to one embodiment, the weight is reduced by providing an internal space between the chainring body and the chainguard. Since the ribs in this space extend radially toward the corresponding risers and the chain rests against the risers during shifting, deformation of the transmission sprocket can be avoided, thus providing the bicycle sprocket with the advantages of light weight and high structural strength.

[0016] Further features, objects and advantages of the present invention will be explained in detail with reference to the following embodiment in conjunction with the accompanying drawings. Brief description of the drawings Fig. 1 shows a schematic exploded view of an embodiment of the transmission sprocket according to the invention; Fig. 2 shows a schematic perspective view of the transmission sprocket according to the invention according to Fig. 1; Fig. 3 shows a schematic sectional view along the section line AA according to Fig. 1; Fig. 4 shows a schematic sectional view along the section line BB according to Fig. 1; Fig. 5 shows a schematic rear view of the chain guard disc according to Fig. 1. Detailed description of the embodiment

[0017] Hereinafter, the orientation words such as "top," "bottom," etc. used in the description of the embodiment according to the present invention are based on the orientation or positional relationship shown in the figures and are used only to simplify the description of the present invention. These orientation words do not indicate or imply that the referenced elements must have a particular orientation or be constructed in a particular orientation. Furthermore, the terms "first" and "second" mentioned in this description or in the claims are used only to name elements or to distinguish different embodiments or ranges and do not serve to limit the upper or lower limit of the number of elements.

[0018] Fig. 1 shows a schematic exploded view of an embodiment of the transmission sprocket according to the invention; Fig. 2 shows a schematic perspective view of the transmission sprocket according to the invention according to Fig. 1; Fig. 3 shows a schematic sectional view along the section line AA according to Fig. 1; Fig. 4 shows a schematic sectional view along the section line BB according to Fig. 1; Fig. 5 shows a schematic rear view of the chain guard disc according to Fig. 1.

[0019] It is based on the Fig. 1 to 5. The transmission sprocket 100 according to an embodiment of the present invention comprises a chainring body 1, a chain guard 2, and climbing aids 3. The chainring body 1 is made of a first non-metallic material and has a plurality of teeth 1a and mounting holes 113 on its radial outer circumference. The chain guard 2 is made of a second non-metallic material and covers one side of the chainring body 1 and, together with the chainring body 1, encloses an interior space S. The interior space S surrounds the axis A of the chainring body 1. The climbing aids 3 are arranged in the corresponding mounting holes 113. Ribs (see the rib 112 and the rib 211 in Fig. 3) are provided in the interior S of one of the two components – chainring body 1 and chainguard disc 2. The ribs 112, 211 extend radially from the axis A in the direction of the corresponding climbing aids 3 and rest against the other of the two components – chainring body 1 and chainguard disc 2.

[0020] In the present embodiment, the axis of the transmission sprocket 100 and the axis of the chain guard disc 2 coincide, for example, with the axis A.

[0021] In the present embodiment, the step-up elements 3 are, for example, pins that are inserted into the chainring body 1 and can be detached therefrom. There are no particular restrictions regarding the shape and material of the step-up elements 3. In particular, the main function of the step-up elements 3 is to provide additional attachment points between the initial chainring and the target chainring when the chain is moved between the chainrings, in order to facilitate the chain ascent. Therefore, it is sufficient as long as the step-up elements protrude from the chainring surface and have a sufficient axial length. The material of the step-up elements 3 is, for example, metal, but is not limited thereto. The material of the step-up elements can also be a non-metallic material, such as a fiber composite material, a polymer material, etc.which is wear-resistant and has the strength required. In the . Fig. 1, in which several climbing aids 3 are present, the shapes of the different climbing aids 3 can be different.

[0022] In the present embodiment, the transmission sprocket 100 further comprises, for example, a spider 4, which is designed, for example, to be connected to a bicycle crank (not shown) and a secondary chainring 5 (see Fig. 2). The spider 4 is, for example, cross-shaped, but the present invention is not subject to any restrictions in this regard. The center of the spider 4 is located on axis A and is provided with a connecting hole 41 suitable for connection to a bicycle crank. The material of the spider 4 is not subject to any particular restrictions. Common materials include steel, iron, fiber composites, polymer composites, aluminum alloys, titanium alloys, etc. Suitable materials can be selected according to the requirements of the application environment.

[0023] As in Fig. 2, the secondary chainring 5 is, for example, a chainring with a smaller diameter than the transmission sprocket 100. When assembling the secondary chainring 5 and the transmission sprocket 100, the secondary chainring 5 is mounted, for example, on the side of the transmission sprocket 100 facing the frame (not shown). The material of the secondary chainring 5 can be selected depending on requirements. In an embodiment not shown, the structure of the secondary chainring 5 can be similar to that of the transmission sprocket 100.

[0024] As in the Fig. 1 to 3, the chainring body 1 consists of a first non-metallic material. The first non-metallic material can be, but is not limited to, a one-piece molded carbon fiber material. A material such as a fiber composite material, a polymer material, etc., that has sufficient strength to meet the requirements can also be used as the material of the first non-metallic material. When the transmission sprocket 100 is combined with a frame, the chainring body 1 is located, for example, on a side of the transmission sprocket 100 facing away from the frame. The chainring body 1 is, for example, annular and has a first disc wall 11, a first ring wall 12, and a plurality of fastening sections 13.

[0025] It is based on the Fig. 1 and Fig. 3. Continuing with the above, in the present embodiment, the first disc wall 11 has a first disc surface 110 on the side facing the chain guard disc 2 (in the present embodiment, also the side of the chainring body 1 facing the frame). The normal direction of the first disc surface 110 runs, for example, parallel to the axis A.

[0026] In the present embodiment, the first disk wall 11 has a plurality of recesses 111, the openings of which are provided on the first disk surface 110. A rib 112 is provided between each two recesses 111. The first disk surface 110 represents, for example, the bottom surface of the recesses 111.

[0027] Continuing with the above, the first disc wall 11 further comprises mounting holes 113 suitable for mounting with the corresponding climbing aids 3. A respective mounting hole 113 is located, for example, on the extension line of the corresponding rib 112, adjacent to the corresponding recess 111, and closer to the axis A than the teeth 1a. The teeth 1a of the chainring body 1 are located, for example, on the outer circumference of the first disc wall 11.

[0028] In the present embodiment, the first annular wall 12 is located on the inner circumference of the first disc wall 11. The first annular wall 12 protrudes, for example, from the surface of the first disc surface 110 along the extension direction parallel to the axis A of the transmission sprocket 100 in the direction of the chain guard disc 2. The outer wall of the first annular wall 12 (the wall surface of the first annular wall 12 facing away from the axis A) is perpendicular to the first disc surface 110, for example, but is not limited thereto.

[0029] Continuing with the above, the fastening sections 13 are, for example, a plurality of blocks that protrude from the inner wall of the first annular wall 12 (the wall surface of the first annular wall 12 facing the axis A) in the direction of the axis A of the transmission sprocket 100. The number of fastening sections 13 corresponds, for example, to the number of plates of the spider 4, and the shape of the fastening sections 13 corresponds, for example, to the shape of the plates of the spider 4.

[0030] When assembling the chainring body 1 and the spider 4, the tabs of the spider 4 are connected to the fastening sections 13 of the chainring body 1. The type of connection between the fastening sections 13 and the spider 4 is not subject to any restrictions and can, for example, be achieved by screw connections using a fastening element or by bonding using an adhesive, as required. The shape of the chainring body 1 can be designed as required. In an embodiment not shown, the chainring body 1 and the spider 4 can be formed as a single piece.

[0031] It is based on the Fig. 1 to 5. Specifically, the chain guard 2 is made of a second non-metallic material. The second non-metallic material may be, but is not limited to, an integrally molded carbon fiber material. A material such as a fiber composite material, a polymer material, etc., that has sufficient strength to meet the requirements can also be used as the material of the second non-metallic material. Furthermore, depending on the application environment, the first non-metallic material and the second non-metallic material may be made of the same material or different materials depending on the specific strength requirements. In the present embodiment, for example, the outer diameter and inner diameter of the chain guard 2 are smaller than the outer diameter and inner diameter, respectively, of the chainring body 1.During assembly, the chain guard disc 2 is located, for example, relative to the chainring body 1 on the side of the transmission sprocket 100 facing the frame. The chain guard disc 2 is, for example, annular and has an annular second disc wall 21 and a second annular wall 22 located on the inner circumference of the chain guard disc 2.

[0032] It is based on the Fig. 1 to 5. In the present exemplary embodiment, the second disc wall 21 has a second disc surface 210 on the side facing the chainring body 1. The second disc wall 21 extends, for example, obliquely from the side near the axis A to the direction remote from the axis A and gradually approaches the chainring body 1. The dimensions of the second disc wall 21 are selected, for example, such that they completely cover the recesses 111 of the chainring body 1 when the chainring body 1 and the chain guard disc 2 are assembled.

[0033] It is based on the Fig. 2 and Fig. 3. In the present embodiment, the second disk wall 21 has a stepped structure, for example, on the surface opposite the second disk surface 210, wherein the second disk wall 21 having the stepped structure has a plurality of first ring portions 212 and a plurality of second ring portions 213. For example, there are three first ring portions 212, and one of the first ring portions 212 is located on the outer circumference of the chain guard disk 2. Each first ring portion 212 extends obliquely from the side near the axis A to the side far from the axis A and gradually approaches the side of the chain guard disk 2 near the chainring body 1. The inclination angles of different first ring portions 212 may be different.For example, in the present embodiment, the angle of inclination of the first ring section 212 located on the outer circumference of the chain guard disc 2 is greater than the angle of inclination of the other two first ring sections 212.

[0034] It is based on the Fig. 2 and Fig. 3. For example, there are two second ring portions 213. Each second ring portion 213 is connected to and located between two adjacent first ring portions 212 and is not parallel to the first ring portions 212. In the present embodiment, on the side opposite the second disc surface 210, the surfaces of the various second ring portions 213 are, for example, parallel to each other and extend in the direction of the axis A, but the present invention is not limited in this regard. With this construction, when changing gears of a bicycle equipped with the transmission sprocket 100, the chain (not shown) can be gradually moved in the direction of the axis A along the surface on the side of the second disc wall 21 facing away from the chainring body 1.

[0035] Since the shape of the second pulley wall 21 is not limited in the present invention, in other embodiments, the stepped structure may be replaced by a continuous curved structure or an inclined structure. In this way, the chain (not shown) can be gradually moved along the second pulley wall 21 in the direction of the axis A.

[0036] As in Fig. 3, the second annular wall 22 extends, for example, along the direction parallel to the axis A of the transmission sprocket 100 from the inner circumference of the second disc surface 210 toward the side on which the chainring body 1 is located, and is designed to be brought into contact with the first annular wall 12 when the chain guard disc 2 and the chainring body 1 are assembled.

[0037] It will be Fig. 3. During assembly, the first annular wall 12 and the second annular wall 22 are in contact with each other, and the portion of the first disk wall 11 near the outer periphery and the outer periphery of the second disk wall 21 are also in contact with each other. In the present embodiment, the inner wall of the second annular wall 22 (the wall surface of the second annular wall 22 near the axis A) abuts the outer wall of the first annular wall 12, so that the interior space S is formed by the first disk surface 110, the second disk surface 210, and the second annular wall 22, but can be configured as needed. Fig. 3 it can be seen that the distance between the first disc surface 110 and the second disc surface 210 gradually decreases along a radial direction from the first annular wall 12 towards the direction away from the axis A.

[0038] As in Fig. As shown in Figure 3, the exact manner in which the chainring body 1 and the chainguard disc 2 are bonded together can be designed as needed, for example, by heating so that the contact points between the chainring body 1 and the chainguard disc 2 melt and bond together. Alternatively, an adhesive can be used between the two.

[0039] Since there are no special restrictions on the size ratios between the chain guard disc 2 and the chainring body 1, the interior space S can be formed by the first disc surface 110, the second disc surface 210 and the first ring wall 12 in an embodiment not shown, according to the relative size ratio between the first ring wall 12 and the second ring wall 22.

[0040] It is based on the Fig. 2, Fig. 4 and Fig. 5. In the present embodiment, the outer circumference of the chain guard 2 has gaps 211a that pass through the chain guard 2 along the direction parallel to the axis A. During assembly of the components, the step-up members 3 are passed through the corresponding gaps 211a and removably inserted into the corresponding mounting holes 113 of the chainring body 1. Due to this construction, the step-up members 3 protrude from the surface of the outermost circumferential ring portion 212 after assembly and are suitable for assisting the engagement of the chain with the teeth 1a during gear shifting.

[0041] The size of each climbing aid 3 can be selected according to requirements. As shown in the Fig. 2 and Fig. 4, for example, the climbing aids 3 protrude not only from the surface of the first ring section 212 located on the outer circumference of the chain guard disc 2, but also from the surface of the second ring section 213 located near the outer circumference of the chain guard disc 2 when the climbing aids 3 are arranged on the chainring body 1 in the direction parallel to the axis A.

[0042] It is based on the Fig. 2 and Fig. 4. In the present embodiment, the climbing aids 3 cover not only a part of the surface of the first ring portion 212 located at the outermost edge of the chain guard disc 2 in the radial direction of the transmission sprocket 100, but also cover the surface adjacent to the second ring portion 213 and do not cover the surfaces of the other first ring portions 212, since each climbing aid 3 has a mushroom-shaped form.

[0043] It is based on the Fig. 2 and Fig. 4. In the present embodiment, the ribs 112 and the ribs 211 are provided on the side of the chainring body 1 and the chain guard plate 2 facing the interior space S, respectively. These ribs (the ribs 112 and the ribs 211) extend along the radial direction of the transmission sprocket 100 and abut one another at the connection point of the chainring body 1 and the chain guard plate 2. The interior space S is divided into several sub-chambers by these ribs (the ribs 112 and the ribs 211).

[0044] It will be Fig. 1. With regard to the ribs in the interior space S, a respective rib 112 of the chainring body 1 is provided, for example, between two recesses 111 of the first disk wall 11, wherein the upper sides of the ribs 112 are aligned with the first disk surface 110. As shown in Fig.5, the ribs 211 of the chain guard disc 2 are provided, for example, between the second disc surface 210 and the second ring wall and are located, for example, opposite the ribs 112 of the chainring body 1.

[0045] It should be understood that the exact shape of the ribs 112 and the ribs 211 can be adapted as needed. For example, in one embodiment not shown, the chainring body 1 can be designed without recesses 111 and thus without ribs 112, so that the ribs 211 of the chainguard disc 2 bear directly against the first disc surface 110. In another embodiment, the chainguard disc 2 can be designed without ribs 211, and the ribs 112 of the chainring body 1 can protrude from the first disc surface 110 and bear against the second disc surface 210 at the connection point of the chainring body 1 and the chainguard disc 2.

[0046] As described above, the transmission sprocket according to the invention reduces weight by providing an internal space between the chainring body and the chainguard. Since the ribs in this space extend radially toward the corresponding risers and the chain rests against the risers during shifting, deformation of the transmission sprocket can be avoided, thus providing the bicycle sprocket with the advantages of light weight and high structural strength.

[0047] Since the chain guard has a stepped structure, the chain can be gradually moved along the surface of the chain guard when changing gears and can be smoothly engaged with the teeth of the chainring body after passing the step-up bars.

[0048] The above description represents only a preferred embodiment of the invention and is not intended to limit the claims. All equivalent changes and modifications that can be made by one skilled in the art in accordance with the description and drawings of the invention are within the scope of the present invention. The scope of the invention is defined by the appended claims. List of reference symbols 100 transmission sprocket 1 chainring body 1a tooth 11 first disc wall 110 first disc surface 111 Deepening 112 Rib 113 Mounting hole 12 first ring wall 13 Fastening section 2 chain guard disc 21 second disc wall 210 second disc surface 211 Rib 211a gap 212 first ring section 213 second ring section 22 second ring wall 3 Climbing aid 4 Spider 41 connecting hole 5 side chainring S interior A axis

Claims

[1] A transmission sprocket comprising: a chainring body made of a first non-metallic material and having a plurality of teeth and at least one mounting hole on its radial outer circumference; a chain guard made of a second non-metallic material and covering one side of the chainring body and enclosing an interior space with the chainring body, the interior space surrounding the axis of the chainring body; and a climbing aid arranged in the at least one mounting hole of the chainring body; wherein a rib is provided in the interior of one of the two components - chainring body and chain guard disc - and extends radially from the axis in the direction of the climbing aid and rests against the other of the two components - chainring body and chain guard disc. [2] A transmission sprocket according to claim 1, wherein the chain guard disc has a second disc wall opposite to the chainring body, the second disc wall extending obliquely from the side near the axis to the direction away from the axis and gradually approaching the chainring body. [3] A transmission sprocket according to claim 2, wherein the second disc wall has a stepped structure and a plurality of first ring portions, each first ring portion extending obliquely from the side near the axis to the side far from the axis and gradually approaching the sprocket body. [4] A transmission sprocket according to claim 3, wherein the second disc wall further comprises at least one second ring portion, the at least second ring portion being connected to two adjacent first ring portions and not extending parallel to the first ring portions. [5] A transmission sprocket according to claim 3, wherein one of the first ring portions is located on the outer circumference of the chain guard disc. [6] Transmission sprocket according to claim 1, wherein the outer circumference of the chain guard disc is provided with at least one gap, wherein the climbing aid is inserted through the at least one gap. [7] A transmission sprocket according to claim 1, wherein the ribs each extend from the chainring body and the chain guard disc and abut each other. [8] A transmission sprocket according to claim 1, wherein the first non-metallic material and the second non-metallic material are the same material. [9] A transmission sprocket according to claim 1, wherein the first non-metallic material and the second non-metallic material are different materials. [10] Transmission sprocket according to claim 1, wherein the climbing aid consists of a non-metallic material.

Images