Rear fork mechanism

Abstract

The utility model discloses a rear fork mechanism which comprises a left rear fork seat and a right rear fork seat which are arranged on a motorcycle engine. The left rear fork seat and the right rear fork seat are respectively provided with a front shaft hole and a rear shaft hole, the middle of the left rear fork seat and the middle of the right rear fork seat are connected in a bilateral symmetry mode through a positioning piece so that the axes of the two front shaft holes in the left rear fork seat and the right rear fork seat can coincide, and the two rear shaft holes are used for being connected with a rear wheel assembly. The front shaft hole of the right rear fork seat is rotationally connected to an engine, the front shaft hole of the left rear fork seat is rotationally connected with an engine driving shaft, and a main chain wheel is arranged on the engine driving shaft and connected with a driven chain wheel through a chain. The main chain wheel, the left rear fork seat and the right rear fork seat form the same rotating center, so that the chain on the main chain wheel, the left rear fork seat and the right rear fork seat can synchronously move around the engine driving shaft, the chain on the main chain wheel and the chain on the driven chain wheel are prevented from being loosened due to bumping in the driving process, and the driving safety is improved.

Description

Technical Field

[0001] This utility model relates to the field of motorcycle component technology, and in particular to a rear fork mechanism. Background Technology

[0002] The motorcycle rear fork, also known as the swingarm or swingarm, is an important component of the motorcycle's suspension system. It primarily connects the rear wheel to the motorcycle's frame, chassis, and shock absorbers. It plays a crucial role in bearing the weight of the motorcycle, securing the rear wheel, and maintaining overall stability. During riding, the rear fork absorbs and cushions vibrations from the road surface, improving riding comfort and stability.

[0003] like Figure 1 As shown, a traditional rear fork 10' is made by welding metal parts 20' together, with a plastic part 30' placed on the metal parts 20' as decoration. Because the rear fork 10' uses multiple metal parts 20' welded together, internal stress exists during the cooling process after welding, which can easily affect the manufacturing precision of the rear fork 10'.

[0004] In addition, such as Figure 2 As shown, the conventional rear fork 10' relies on a dedicated rear fork fixing axle 11' on the frame 40', allowing the rear fork 10' to rotate slightly around the rear fork fixing axle 11' during riding. In contrast, the engine axle 51' on the engine 50', which drives the rear wheel, is independently mounted. The engine axle 51' is equipped with a master sprocket 61', which drives the driven sprocket 63' on the rear fork 10' via a chain 62'. However, although the chain 62' moves parallel to the rear fork 10' during riding, when encountering bumps or other obstacles, because the axis of the engine shaft 51' does not coincide with the axis of the rear fork fixed shaft 11', the rear fork 10' will rotate slightly around the rear fork fixed shaft 11', while the chain 62' will rotate slightly around the engine drive shaft 51'. The two cannot move synchronously, resulting in the chain being sometimes loose and sometimes tight, causing abnormal noise and affecting transmission efficiency, posing a certain safety hazard. Furthermore, the added rear fork fixed shaft 11' not only occupies a large amount of space but also increases the assembly complexity of the rear fork 10'. Utility Model Content

[0005] The purpose of this invention is to provide a rear fork mechanism that ensures the synchronous movement of the rear fork and chain during riding, thereby guaranteeing riding safety.

[0006] To achieve the above objectives, the solution of this utility model is as follows: a rear fork mechanism, including a left rear fork mount and a right rear fork mount mounted on a motorcycle engine; both the left and right rear fork mounts are provided with a front axle hole and a rear axle hole, and the middle parts of the left and right rear fork mounts are symmetrically connected by a positioning member so that the axes of the two front axle holes on the left and right rear fork mounts coincide, the two rear axle holes are used to connect to the rear wheel assembly, the rear wheel assembly is provided with a driven sprocket, the front axle hole of the right rear fork mount is rotatably connected to the engine, the front axle hole of the left rear fork mount is rotatably connected to the engine drive shaft, the engine drive shaft is provided with a master sprocket, and the master sprocket is connected to the driven sprocket through a chain.

[0007] In a preferred embodiment, the positioning components are a first positioning bushing and a positioning bolt. The left rear fork seat is provided with a left threaded through hole, and the right rear fork seat is provided with a right threaded through hole. The left and right threaded through holes are symmetrically arranged. The first positioning bushing is disposed in the left and right threaded through holes. The positioning bolt passes through the positioning bushing and the two threaded through holes and is threadedly engaged with the two threaded through holes to achieve locking and positioning of the left and right rear fork seats.

[0008] In a preferred embodiment, the left threaded through hole has a concave first stepped surface, the right threaded through hole has a concave second stepped surface, one end of the first positioning bushing is embedded in the left threaded through hole and abuts against the first stepped surface, and the other end of the first positioning bushing is embedded in the right threaded through hole and abuts against the second stepped surface.

[0009] In a preferred embodiment, the length of one end of the first positioning bushing embedded in the left threaded through hole and abutting against the first stepped surface is equal to the length of the other end of the first positioning bushing embedded in the right threaded through hole and abutting against the second stepped surface.

[0010] In a preferred embodiment, the engine also includes a first bearing and a second bearing. A third stepped surface is provided on the engine drive shaft on the left side of the engine. The first bearing is fixedly sleeved on the third stepped surface. The front axle hole of the left rear fork is fixedly installed on the first bearing. A mounting groove is provided in the recess on the right side of the engine. The second bearing is fixedly installed at the bottom of the mounting groove. The front axle hole of the right rear fork is installed on the second bearing by fasteners.

[0011] In a preferred embodiment, the fastener includes a first fastening bolt, a nut, and a washer. The front axle hole of the right rear fork is provided with a fastening thread. One end of the first fastening bolt is fixedly connected to the second bearing. The middle part of the first fastening bolt is fixedly connected to the front axle hole of the right rear fork through a threaded engagement. The washer is sleeved on the other end of the first fastening bolt and abuts against the front axle hole of the right rear fork. The nut is fixedly sleeved on the other end of the first fastening bolt. The axis of the first fastening bolt coincides with the axis of the engine drive shaft.

[0012] In a preferred embodiment, the device further includes a second positioning bushing and a seal. The second positioning bushing is fitted onto one end of the first fastening bolt and abuts against the second bearing. The seal is disposed between the second positioning bushing and the side wall of the mounting groove.

[0013] In a preferred embodiment, the first bearing is a needle roller bearing and the second bearing is a deep groove ball bearing.

[0014] In a preferred embodiment, a fixing cover is also included, wherein the fixing cover and the main sprocket are fixedly sleeved on the left end of the engine drive shaft, and the fixing cover is used to cover the main sprocket.

[0015] In a preferred embodiment, a second fastening bolt is also included. A threaded blind hole is provided on the left side of the engine. The fixing cover and the left rear fork seat are provided with fastening through holes at positions that match the threaded blind hole. The second fastening bolt passes through the fastening through holes and cooperates with the threaded blind hole to lock and fix the fixing cover and the left rear fork seat to the engine.

[0016] The beneficial effects of this utility model after adopting the above solution are as follows: The middle parts of the left and right rear fork seats are symmetrically connected by positioning components, so that the axes of the two front axle holes on the left and right rear fork seats coincide. The two rear axle holes are used to connect the rear wheel assembly, and the rear wheel assembly is provided with a driven sprocket. The front axle hole of the right rear fork seat is rotatably connected to the engine, and the front axle hole of the left rear fork seat is rotatably connected to the engine drive shaft. The engine drive shaft is provided with a master sprocket, which is connected to the driven sprocket through a chain. The structure is simple, easy to install and remove, and effectively improves space utilization. The master sprocket forms the same rotation center with the left and right rear fork seats, so that the chain on the master sprocket can move synchronously with the left and right rear fork seats around the engine drive shaft, avoiding the chain on the master sprocket and driven sprocket from being sometimes tight and sometimes loose due to bumps during driving, thus improving driving safety. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the existing rear fork structure;

[0018] Figure 2 This is a side view of the existing rear fork mounted on the frame;

[0019] Figure 3 This is an assembly diagram showing the left and right rear fork seats symmetrically connected by positioning components.

[0020] Figure 4 This is a schematic diagram of the present invention, showing the installation of a first bearing on the engine drive shaft;

[0021] Figure 5 This is an assembly diagram of the left and right rear fork mounts of this utility model mounted on the engine;

[0022] Figure 6This is a partial cross-sectional view of the right rear fork mount of this utility model installed on the right side of the engine;

[0023] Figure 7 This is a structural schematic diagram of the first fastening bolt of this utility model.

[0024] Label Explanation:

[0025] 11. Left rear fork mount; 12. Right rear fork mount; 120. Right threaded through hole; 13. Front axle hole; 21. First locating bushing; 22. Locating bolt; 31. Engine; 32. Engine drive shaft; 33. Third stepped surface; 34. Mounting slot; 41. Main sprocket; 42. Drive sprocket; 43. Chain; 51. First bearing; 52. Second bearing; 6. Fastener; 61. First fastening bolt; 62. Nut; 63. Washer; 64. Second locating bushing; 65. Seal; 71. Retaining cap; 72. Second fastening bolt; 8. Rear wheel assembly. Detailed Implementation

[0026] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0027] This embodiment provides a rear fork mechanism, such as Figures 3 to 7 As shown, the motorcycle includes a left rear fork mount 11 and a right rear fork mount 12 mounted on the motorcycle engine 31. Both the left rear fork mount 11 and the right rear fork mount 12 are provided with a front axle hole 13 and a rear axle hole. The middle parts of the left rear fork mount 11 and the middle parts of the right rear fork mount 12 are symmetrically connected by a positioning member so that the axes of the two front axle holes 13 on the left rear fork mount 11 and the right rear fork mount 12 coincide. The two rear axle holes are used to connect to the rear wheel assembly 8. The rear wheel assembly 8 is provided with a driven sprocket 42. The front axle hole 13 of the right rear fork mount 12 is rotatably connected to the engine 31. The front axle hole 13 of the left rear fork mount 11 is rotatably connected to the engine drive shaft 32. The engine drive shaft 32 is provided with a master sprocket 41. The master sprocket 41 is connected to the driven sprocket 42 through a chain 43.

[0028] In this embodiment, the middle parts of the left rear fork mount 11 and the right rear fork mount 12 are symmetrically connected by positioning components, enabling precise positioning during installation and improving ease of installation. This also ensures that the axes of the front axle holes 13 on both sides coincide, enhancing the stability of the rear fork structure. Furthermore, both the left rear fork mount 11 and the right rear fork mount 12 in this embodiment are made of aluminum and integrally molded, allowing them to function as both functional and aesthetic components. The simple structure and ingenious design make them suitable for applications in vehicles such as motorcycles or electric vehicles.

[0029] In this embodiment, the front axle hole 13 of the left rear fork 11 is rotatably connected to the engine drive shaft 32 on the left side of the engine 31, and the front axle hole 13 of the right rear fork 12 is rotatably connected to the right side of the engine 31. Since the axes of the two front axle holes 13 on the left and right rear forks 11 and 12 coincide, the left and right rear forks 11 and 12 are installed behind the engine 31, and their axes also coincide with the axis of the engine drive shaft 32, thus forming the same rotation center. The engine drive shaft 32 is provided with a master sprocket 41, which is connected to the driven sprocket 42 on the rear wheel assembly 8 via a chain 43. This arrangement allows the chain 43 on the master sprocket 41 to move synchronously with the left and right rear forks 11 and 12 around the engine drive shaft 32, preventing the chain 43 on the master sprocket 41 and driven sprocket 42 from becoming tense and loose due to bumps during driving, thus improving driving safety and simplifying the structure.

[0030] like Figure 3 As shown, the positioning components are a first positioning bushing 21 and a positioning bolt 22. The left rear fork 11 is provided with a left threaded through hole, and the right rear fork 12 is provided with a right threaded through hole 120. The left threaded through hole and the right threaded through hole 120 are symmetrically arranged. The first positioning bushing 21 is disposed in the left threaded through hole and the right threaded through hole 120. The positioning bolt 22 passes through the positioning bushing and the two threaded through holes and is threadedly engaged with the two threaded through holes to achieve locking and positioning of the left rear fork 11 and the right rear fork 12.

[0031] In this embodiment, the positioning bolt 22 passes through the positioning bushing and is threadedly connected to the left and right threaded through holes, achieving a tight connection between the left rear fork 11 and the right rear fork 12. This ensures connection strength and stability, and improves reliability and safety in use. The first positioning bushing 21 is set in the left threaded through hole and the right threaded through hole 120, with a simple structure that makes the connection between the left rear fork 11 and the right rear fork 12 more convenient, easy to install and remove, and beneficial for later maintenance.

[0032] Furthermore, the left threaded through hole is provided with a concave first step surface, and the right threaded through hole 120 is provided with a concave second step surface. One end of the first positioning bushing 21 is embedded in the left threaded through hole and abuts against the first step surface, and the other end of the first positioning bushing 21 is embedded in the right threaded through hole 120 and abuts against the second step surface.

[0033] In this embodiment, the first positioning bushing 21 is directly set in the first step surface of the left threaded through hole and the second step surface of the right threaded through hole 120, which simplifies the installation and positioning process and improves convenience.

[0034] Furthermore, in this embodiment, the length of one end of the first positioning bushing 21 embedded in the left threaded through hole and abutting against the first step surface is equal to the length of the other end of the first positioning bushing 21 embedded in the right threaded through hole 120 and abutting against the second step surface. However, it is not limited to this. This can ensure that the first positioning bushing 21 is evenly stressed in the left rear fork seat 11 and the right rear fork seat 12, making the positioning of the left rear fork seat 11 and the right rear fork seat 12 more accurate and convenient during connection.

[0035] like Figures 4 to 6 As shown, it also includes a first bearing 51 and a second bearing 52. A third step surface 33 is provided on the engine drive shaft 32 on the left side of the engine 31. The first bearing 51 is fixedly sleeved on the third step surface 33. The front axle hole 13 of the left rear fork 11 is fixedly installed on the first bearing 51. A mounting groove 34 is provided inward on the right side of the engine 31. The second bearing 52 is fixedly installed at the bottom of the mounting groove 34. The front axle hole 13 of the right rear fork 12 is installed on the second bearing 52 by fasteners 6.

[0036] This embodiment sets up a first bearing 51 and a second bearing 52, with the axes of the first bearing 51 and the second bearing 52 coinciding with the axis of the engine drive shaft 32. The front axle hole 13 of the left rear fork 11 is installed on the first bearing 51, and the front axle hole 13 of the right rear fork 12 is installed on the second bearing 52. This ensures that when encountering bumps during driving, the left rear fork 11 and the right rear fork 12 can rotate slightly around the axis of the engine drive shaft 32 through the first bearing 51 and the second bearing 52. That is, the left rear fork 11 and the right rear fork 12 have the same rotation center as the engine drive shaft 32, thus ensuring driving safety.

[0037] like Figures 5 to 7 As shown, the fastener 6 includes a first fastening bolt 61, a nut 62, and a washer 63. The front axle hole 13 of the right rear fork 12 is provided with a fastening thread. One end of the first fastening bolt 61 is fixedly connected to the second bearing 52. The middle part of the first fastening bolt 61 is fixedly connected to the front axle hole 13 of the right rear fork 12 through a threaded engagement. The washer 63 is sleeved on the other end of the first fastening bolt 61 and abuts against the front axle hole 13 of the right rear fork 12. The nut 62 is fixedly sleeved on the other end of the first fastening bolt 61. The axis of the first fastening bolt 61 coincides with the axis of the engine drive shaft 32.

[0038] In this embodiment, the first fastening bolt 61 engages with the threaded connection of the front axle hole 13 of the right rear fork 12, and the nut 62 and washer 63 work together to form a robust mechanical connection structure capable of withstanding large axial and radial loads, ensuring a stable connection between the right rear fork 12 and the engine 31. This design also facilitates the loading and unloading process and is beneficial for later maintenance.

[0039] like Figure 6As shown, it also includes a second positioning bushing 64 and a seal 65. The second positioning bushing 64 is fitted through one end of the first fastening bolt 61 and abuts against the second bearing 52. The seal 65 is sealed between the second positioning bushing 64 and the side wall of the mounting groove 34.

[0040] In this embodiment, the first fastening bolt 61 is in the shape of a coaxial cylinder, such as... Figure 6 and Figure 7 As shown, the diameter of one end of the first fastening bolt 61 is smaller than the diameter of the other end of the first fastening bolt 61, and a stepped surface is formed in the middle of the first fastening bolt 61. One end of the second positioning bushing 64 abuts against the second bearing 52, and the other end of the second positioning bushing 64 abuts against the stepped surface in the middle of the first fastening bolt 61. In this embodiment, the second positioning bushing 64 can improve the stability between the first fastening bolt 61 and the second bearing 52, and the seal 65 provided between the second positioning bushing 64 and the side wall of the mounting groove 34 effectively prevents external dust, moisture and other impurities from entering the bearing, thereby protecting the cleanliness and lubrication performance of the bearing and improving its service life. The seal 65 in this embodiment can be an oil seal, but is not limited to it; other structures of seal 65 can also be used in other embodiments.

[0041] like Figures 4 to 6 As shown, the first bearing 51 is a needle roller bearing, and the second bearing 52 is a deep groove ball bearing. Since the front axle hole 13 of the left rear fork 11 is rotatably connected to the engine drive shaft 32, the first bearing 51 in this embodiment is a needle roller bearing. Needle roller bearings can withstand a larger load per unit area, ensuring driving safety. The right rear fork 12 is rotatably located on the right side of the engine 31, and the second bearing 52 needs to be installed in the recessed mounting groove 34 on the right side of the engine 31. Therefore, in this embodiment, the second bearing 52 is a deep groove ball bearing, which is smaller in size, has a certain load-bearing capacity, and has a simple structure. Of course, different bearings can be selected in other embodiments depending on the actual situation.

[0042] like Figure 4 As shown, it also includes a fixing cover 71, which and the main sprocket 41 are fixedly sleeved on the left end of the engine drive shaft 32. The fixing cover 71 is used to cover the main sprocket 41.

[0043] The fixing cover 71 in this embodiment can effectively cover and protect the main sprocket 41, preventing it from being directly corroded by the external environment, improving its service life, and ensuring driving safety. At the same time, the fixing cover 71 can also improve the overall appearance and aesthetics.

[0044] like Figure 4As shown, it also includes a second fastening bolt 72. A threaded blind hole is provided on the left side of the engine 31. The fixing cover 71 and the left rear fork seat 11 are provided with fastening through holes at positions that match the threaded blind hole. The second fastening bolt 72 passes through the fastening through hole and cooperates with the threaded blind hole to lock and fix the fixing cover 71 and the left rear fork seat 11 onto the engine 31.

[0045] In this embodiment, the second fastening bolt 72 passes through the fastening through hole and matches the threaded blind hole, realizing a firm connection between the fixed cover 71 and the left rear fork seat 11 and the engine 31. The structure is simple, easy to install and remove, has high strength and stability, can withstand large loads and vibrations, and ensures the stability and safety of the motorcycle during driving.

[0046] The directional terms used in this specification are defined relative to the structures shown in the accompanying drawings. They are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive.

[0047] The above description is only a preferred embodiment of this utility model and is not intended to limit the design of this case. All equivalent changes made based on the key design of this case shall fall within the protection scope of this case.

Claims

1. A rear fork mechanism, characterized in that: This includes the left and right rear fork mounts mounted on the motorcycle engine; Both the left and right rear fork mounts have front and rear axle holes. The middle parts of the left and right rear fork mounts are symmetrically connected by positioning components, so that the axes of the two front axle holes on the left and right rear fork mounts coincide. The two rear axle holes are used to connect to the rear wheel assembly. The rear wheel assembly is equipped with a driven sprocket. The front axle hole of the right rear fork mount is rotatably connected to the engine. The front axle hole of the left rear fork mount is rotatably connected to the engine drive shaft. The engine drive shaft is equipped with a master sprocket, which is connected to the driven sprocket via a chain.

2. The rear fork mechanism as described in claim 1, characterized in that: The positioning components are a first positioning bushing and a positioning bolt. The left rear fork seat is provided with a left threaded through hole, and the right rear fork seat is provided with a right threaded through hole. The left threaded through holes and the right threaded through holes are symmetrically arranged. The first positioning bushing is set in the left threaded through hole and the right threaded through hole. The positioning bolt passes through the positioning bushing and the two threaded through holes and is threadedly engaged with the two threaded through holes to achieve locking and positioning of the left rear fork seat and the right rear fork seat.

3. A rear fork mechanism as described in claim 2, characterized in that: The left threaded through hole has a concave first step surface, and the right threaded through hole has a concave second step surface. One end of the first positioning bushing is embedded in the left threaded through hole and abuts against the first step surface, and the other end of the first positioning bushing is embedded in the right threaded through hole and abuts against the second step surface.

4. A rear fork mechanism as described in claim 3, characterized in that: The length of one end of the first positioning bushing embedded in the left threaded through hole and abutting against the first step surface is equal to the length of the other end of the first positioning bushing embedded in the right threaded through hole and abutting against the second step surface.

5. A rear fork mechanism as described in claim 1, characterized in that: It also includes a first bearing and a second bearing. A third step surface is provided on the engine drive shaft on the left side of the engine. The first bearing is fixedly sleeved on the third step surface. The front axle hole of the left rear fork is fixedly installed on the first bearing. A mounting groove is provided in the recess on the right side of the engine. The second bearing is fixedly installed at the bottom of the mounting groove. The front axle hole of the right rear fork is installed on the second bearing by fasteners.

6. A rear fork mechanism as described in claim 5, characterized in that: The fasteners include a first fastening bolt, a nut, and a washer. The front axle hole of the right rear fork is provided with a fastening thread. One end of the first fastening bolt is fixedly connected to the second bearing. The middle part of the first fastening bolt is fixedly connected to the front axle hole of the right rear fork through a threaded engagement. The washer is sleeved on the other end of the first fastening bolt and abuts against the front axle hole of the right rear fork. The nut is fixedly sleeved on the other end of the first fastening bolt. The axis of the first fastening bolt coincides with the axis of the engine drive shaft.

7. A rear fork mechanism as described in claim 6, characterized in that: It also includes a second positioning bushing and a seal. The second positioning bushing is fitted onto one end of the first fastening bolt and abuts against the second bearing. The seal is disposed between the second positioning bushing and the side wall of the mounting groove.

8. A rear fork mechanism as described in claim 5, characterized in that: The first bearing is a needle roller bearing, and the second bearing is a deep groove ball bearing.

9. A rear fork mechanism as described in claim 1, characterized in that: It also includes a fixing cover, which is fixedly sleeved on the left end of the engine drive shaft along with the main sprocket. The fixing cover is used to cover the main sprocket.

10. A rear fork mechanism as described in claim 9, characterized in that: It also includes a second fastening bolt. A threaded blind hole is provided on the left side of the engine. The fixing cover and the left rear fork seat are provided with fastening through holes at positions that match the threaded blind hole. The second fastening bolt passes through the fastening through hole and cooperates with the threaded blind hole to lock and fix the fixing cover and the left rear fork seat to the engine.

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