Shaft stick structure matched with five-way pipe and spline tooth connector of bicycle center shaft line mark

Abstract

The utility model provides a shaft stick structure matched with a five-way pipe and a spline tooth interface of a bicycle center shaft line mark. The shaft stick structure comprises a left shaft bowl, a right shaft bowl and a torque sensor. A first shaft rod, a second shaft rod and an axial bolt; spline teeth embedded with the spline teeth of the crank interface of the pedal are arranged on the outer edges of one ends of the first shaft roller and the second shaft roller; the second shaft roller is of a hollow columnar structure; the axial bolt is provided with an axial inner threaded hole which is matched and fixed with the end part of the first shaft roller; and the axial bolt penetrates through the axial middle hole of the second shaft roller and is combined and fixed with the inner threaded hole of the first shaft roller. By adopting the shaft roller structure, the shaft roller is divided into two sections which are respectively connected and fixed with the spline teeth on the torque sensor through the spline teeth, the structure is stable, the assembly is simple, and meanwhile, the technical problem that a standard interface of the spline teeth cannot be realized on a five-way pipe of an axle line mark in a bicycle is solved.

Description

Technical Field

[0001] This utility model relates to the shaft structure of electric bicycles or electric-assisted bicycles, and in particular, to a shaft structure that can be adapted to the bottom bracket and spline tooth interface of the "Bicycle Bogie" standard. Background Technology

[0002] Electric bicycles, or electric-assisted bicycles (hereinafter collectively referred to as "electric bicycles"), are a type of bicycle based on a bicycle structure, equipped with a pedaling torque sensing device and an electric drive assist device. Due to their combined functions as a recreational and fitness activity and a means of transportation, they have gained widespread popularity in the global market.

[0003] Typically, a torque sensor is mounted on the bottom bracket axle inside the bottom bracket of an electric bicycle, with the cranks of the left and right pedals connected to opposite ends of the axle. The torque sensor detects the magnitude of the torque transmitted from the pedals via the cranks, converts the torque into an electrical signal, and transmits it to the drive control device. This signal then adjusts the output drive force of the electric drive unit, thus enabling the electric assist function.

[0004] In electric bicycles, the bottom bracket of the bicycle bottom bracket (hereinafter referred to as "bicycle bottom bracket standard") conforming to the People's Republic of China Light Industry Standard QB / T1884-2018 has been widely used and formed a broad industry standard. Most other accessories on electric bicycles are configured according to the dimensions of the bottom bracket of the bicycle bottom bracket standard and cannot be changed. For example... Figure 5A , 5B As shown in Figure 5C, most axle rollers 11 that are compatible with the bottom bracket tube 100 of bicycles have a generally square-shaped end 111. The middle section of the axle roller is fitted into the central hole of the torque sensor 20. The middle section of the axle roller 11 and the torque sensor are fitted into the bottom bracket tube 100. A left axle cup 5 and a right axle cup 6 are installed at the left and right ends of the bottom bracket tube 100. The two ends 111 of the axle roller extend out of the bottom bracket tube 100 and are fitted into the square interface of the crank for connection and fixation. Since the connection interface between the crank and the end 111 of the axle roller is a core force-bearing part of the bicycle, it is prone to wear and loosening during use, affecting the performance of the electric bicycle.

[0005] like Figure 6A and Figure 6BAs shown, a new type of splined interface shaft 12 has been developed in the high-end electric bicycle market, such as the European standard D / 26-Mar-01 (the full English name is "The International Spline Interface Standard", hereinafter referred to as "European ISIS Splined Interface") or the Shimano (Japan Shimano Corporation) crank splined interface (hereinafter referred to as Shimano Splined Interface). For the sake of simplicity, this article refers to the above two standards together as "splined interface standard". In this structure, a splined interface structure is set along the periphery of the end of the shaft 12, including multiple racks that are generally parallel to the length direction of the shaft. Correspondingly, a strip-shaped groove matching the tooth shape is set on the inner periphery of the crank end interface. The racks and grooves cooperate to tightly lock and fix the end of the crank and the end of the shaft. However, the splined interface standard requires the end of the shaft 12 to meet a specific radial dimension, and a shaft that meets this radial dimension cannot pass through the center hole of the torque sensor 20 of the bottom bracket 100 that is adapted to the bicycle bottom bracket. Therefore, there are significant obstacles to implementing a splined interface on the shaft of the bottom bracket 100 that is adapted to the bicycle bottom bracket.

[0006] To address the aforementioned issues, there is an urgent need to provide a shaft structure that can be used with both spline standard interfaces and bicycle bottom bracket bottom brackets. Utility Model Content

[0007] One of the purposes of this utility model is to provide an axle structure for electric bicycles that can use a standard spline interface and is compatible with the bottom bracket of a bicycle.

[0008] One of the objectives of this utility model is to provide an axle structure for electric bicycles that can meet the above requirements and ensure the concentricity of the axle rollers.

[0009] One of the objectives of this utility model is to provide an axle structure for an electric bicycle that can meet the above requirements and ensure that the two cranks are connected at a 180-degree angle.

[0010] This utility model discloses a shaft structure adapted to a standard bottom bracket torque sensor and a splined interface, comprising a left shaft cup, a right shaft cup, and a torque sensor; the torque sensor is a hollow cylindrical structure; the left and right shaft cups are respectively provided with threads that mate with the inner wall of the bottom bracket; it also includes a first shaft, a second shaft, and an axial bolt; the outer edge of the end of the first shaft near the left shaft cup and the outer edge of the end of the second shaft near the right shaft cup are provided with first splined teeth that engage with the splined teeth of the crank interface of the pedal; the outer edge of the middle part of the first shaft is provided with second splined teeth; the outer edge of the end of the first shaft away from the left shaft cup is provided with third splined teeth, and the end is provided with an internally threaded hole along the axial direction; the inner wall of the end of the torque sensor near the left shaft cup is provided with fourth splined teeth that mate with the second splined teeth;

[0011] The second shaft is a hollow columnar structure; the inner wall of the end of the second shaft near the left shaft cup is provided with a fifth spline tooth that mates with the third spline tooth, and the inner wall of the end of the second shaft near the right shaft cup is provided with a boss.

[0012] The axial bolt is provided with an external thread that mates with the internal threaded hole; the axial bolt passes through the axial central hole of the second shaft and engages with the first shaft, and the nut of the axial bolt abuts against the boss.

[0013] Preferably, the shape and size of the first spline tooth are the same as or similar to the shape and size of the standard spline tooth interface.

[0014] Preferably, the end of the first shaft away from the left shaft cup is provided with an annular boss; the interior of the second shaft is provided with an annular groove that engages with the annular boss near the fifth spline tooth.

[0015] Preferably, the third spline tooth is provided with a first limiting part, and the fifth spline tooth is provided with a second limiting part, wherein the first limiting part and the second limiting part are engaged.

[0016] Preferably, the axis of the first shaft includes a hollow space.

[0017] Preferably, an elastic pad is provided at the spline interface between the first shaft and the torque sensor, or at the interface between the second shaft and the torque sensor, or at the interface between the inner diameter of the torque sensor and the outer diameter of the second shaft.

[0018] Preferably, the outer radius of the left side portion of the first spline tooth on the first shaft is greater than the inner diameter of the left end of the torque sensor; the edge diameter of the right end of the second shaft is greater than the inner diameter of the right end of the torque sensor.

[0019] Preferably, the outer edge of the end of the torque sensor away from the left axle cup is provided with a sixth spline tooth that engages with the axial spline tooth of the inner wall of the central hole of the bottom bracket of the electric bicycle, and a thread that engages with the thread of the locking nut, the sixth spline tooth extending out of the bottom bracket tube.

[0020] Preferably, it also includes a locking nut; the locking nut is fixed by an internal thread to an external thread at the end of the torque sensor away from the left axle cup.

[0021] The axle structure of this utility model divides the axle into two sections, which are connected and fixed by spline teeth. These sections are also connected and fixed to the spline teeth on the torque sensor. The structure is stable and easy to assemble. At the same time, it solves the technical problem that a standard spline tooth interface structure cannot be realized on the bottom bracket of a bicycle. This greatly improves the market versatility and manufacturing cost of the axle and torque sensor that are compatible with the bottom bracket of a bicycle, and has great commercial and industrial value. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the assembly structure of the electric bicycle axle, torque sensor, and axle cup according to the present invention.

[0023] Figure 2 This is a cross-sectional schematic diagram of the assembly structure of the axle, torque sensor, and axle cup of the electric bicycle according to this utility model.

[0024] Figure 3A This is a schematic diagram of the second axle structure of the electric bicycle according to the present invention.

[0025] Figure 3B This is a schematic diagram of the torque sensor structure of the axle roller of the electric bicycle according to this utility model.

[0026] Figure 4 This is a three-dimensional schematic diagram of the assembly structure of the axle, torque sensor, and axle cup of the electric bicycle of this utility model.

[0027] Figure 5A This is a schematic diagram of the bottom bracket structure of a bicycle's center column in the prior art.

[0028] Figure 5B This is a schematic diagram of the shaft structure for adapting the bottom bracket of a bicycle to the existing technology.

[0029] Figure 5C This is a schematic diagram of the axle assembly structure for the bottom bracket of a bicycle in the prior art.

[0030] Figure 6A This is a schematic diagram of the assembly structure of a standard splined interface shaft in the prior art.

[0031] Figure 6B This is a schematic diagram of the shaft structure of the standard spline interface in the prior art.

[0032] Symbol explanation:

[0033] 1. First shaft; 101. Second spline tooth; 102. Third spline tooth; 103. Internal thread; 104. Annular boss; 105. First limiting part; 2. Torque sensor; 201. Fourth spline tooth; 3. Second shaft; 301. Fifth spline tooth; 302. Annular groove; 303. O-ring groove; 304. Boss; 305. Second limiting part; 4. Axial bolt; 5. Left shaft cup; 6. Right shaft cup; 7. Elastic pad; 8. Elastic pad; 9. Locking nut; 100. Five-way tube; 11. Shaft; 111. Shaft end; 21. Spline tooth standard interface torque sensor; 12. Spline tooth standard interface shaft; Detailed Implementation

[0034] The following is a detailed description of a preferred embodiment of the present invention:

[0035] like Figures 1 to 4 The embodiment shown in this utility model provides a shaft structure adapted to the torque sensor and spline interface of the bottom bracket of a bicycle, including a left shaft cup 5, a right shaft cup 6, and a torque sensor 2; the torque sensor 2 is generally a hollow columnar structure; the left shaft cup 5 and the right shaft cup 6 are respectively provided with threads that mate with the threads of the inner wall of the bottom bracket; it also includes: a first shaft 1, a second shaft 3, and an axial bolt 4, the outer edge of the end of the first shaft 1 near the left shaft cup 5 and the outer edge of the end of the second shaft 3 near the right shaft cup 6 are provided with first spline teeth that engage with the spline teeth of the crank interface of the pedal;

[0036] The outer edge of the middle part of the first shaft roller 1 is provided with a second spline tooth 101; the outer edge of the end of the first shaft roller 1 away from the left shaft cup 5 is provided with a third spline tooth 102, and the end is provided with an internal thread hole along the axial direction; the inner wall of the end of the torque sensor 2 near the left shaft cup 5 is provided with a fourth spline tooth 201 that cooperates with the second spline tooth.

[0037] The second shaft roller 3 is a hollow columnar structure; the inner wall of the end of the second shaft roller 3 near the left shaft cup 5 is provided with a fifth spline tooth 301 that mates with the third spline tooth 102, and the inner wall of the end of the second shaft roller 3 near the right shaft cup 6 is provided with a boss 304; the axial bolt 4 is provided with an external thread that mates with the internal thread hole; the axial bolt 4 passes through the axial central hole of the second shaft roller 3 and is connected to the first shaft roller 1, and the nut of the axial bolt 4 abuts against the boss 304.

[0038] In addition, the outer radius of the left side of the first spline tooth 101 of the first shaft 1 is greater than the inner diameter of the left end of the torque sensor 2; the edge diameter of the right end of the second shaft 3 is greater than the inner diameter of the right end of the torque sensor 2, so that the axial bolt 4 can more firmly lock the first shaft 1, the torque sensor 2 and the second shaft 3 in the length direction of the shaft.

[0039] like Figure 5A , 5B Figure 5C shows a schematic diagram of the bottom bracket tube 100 and axle of a bicycle bottom bracket. This standard is used in most electric bicycles and bicycles in the Chinese market, resulting in a high market share. The bicycle bottom bracket standard specifies clear requirements for the diameter, length, wall thickness, and threads of the bottom bracket tube 100. The geometric dimensions of the electric bicycle frame, pedals, cranks, the bottom bracket axle 11 passing through the bottom bracket tube, and the torque sensor 2 mounted on the bottom bracket axle are all limited by the dimensions of the bottom bracket tube 100. Currently, the ends 111 of the axle 11, which are adapted to the bottom bracket tube of bicycle bottom brackets, mostly adopt a square structure, fitting into the square interface on the crank. While the assembly structure is simple, wear and wobble can easily occur between the axle and the crank, affecting the performance of the electric bicycle.

[0040] like Figure 6A , 6BAs shown, the standard spline interface is a common interface structure used in high-end electric bicycles. It should be noted that the standard spline interface referred to in this invention refers to the shape and size of the first spline tooth. The shapes and sizes of the second, third, fourth, fifth, and sixth spline teeth can be set as needed. In addition, besides being compatible with the standard spline interface, the shaft structure of this invention can also have the first spline tooth set to a shape and size that differs from, but is similar to, the central shaft interface structure. The middle section of the shaft 12 is fitted into the central hole of the torque sensor 21. The interface structure between the shaft and the crank generally consists of toothed structures on the outer edges of both ends of the shaft 12. These toothed structures include multiple racks generally parallel to the length of the shaft, with adjacent racks spaced by strip-shaped grooves. The shape of this toothed structure resembles the keys of a piano, hence it is referred to as a spline by those skilled in the art. The inner walls of the pedal crank interfaces corresponding to both ends of the axle 12 also adopt a similar toothed structure; during assembly, the rack and groove on the crank interface engage and fix with the groove and rack on the axle, thereby tightly fixing the crank to the axle. In the above description of the technical solution of this utility model, the first spline tooth, the second spline tooth 101, the third spline tooth 102, the fourth spline tooth 201, and the fifth spline tooth 301 all adopt similar spline tooth structures. The crank and bottom bracket axle connection interface structure commonly used in electric bicycles with spline tooth standard interfaces has special requirements for the radial dimensions of the axle 12, the radial dimensions of the torque sensor 21, and the radial dimensions of the bottom bracket tube, which are significantly different from the bottom bracket tube of the bicycle bottom bracket.

[0041] The standard spline interface has certain requirements for the radial dimension of the shaft, which is usually greater than 20mm in diameter. The radial dimension of this shaft is larger than that of the shaft of the bottom bracket of a bicycle, which is also equipped with a torque sensor. Therefore, it is not possible to directly implement a spline interface on the shaft of the bottom bracket and the crank of a bicycle.

[0042] The axle structure of this utility model divides the axle into two sections, which are connected and fixed by spline teeth. These sections are also connected and fixed to the spline teeth on the torque sensor. The structure is stable and easy to assemble. At the same time, it solves the technical problem of the spline tooth standard interface that cannot be realized on the bottom bracket of bicycles. This greatly improves the market versatility and manufacturing cost of the axle and torque sensor that are compatible with the bottom bracket of bicycles, and has great commercial and industrial value.

[0043] In addition, as disclosed in the above embodiments, the shaft structure for adapting the bicycle bottom bracket torque sensor and spline interface can preferably have the shape and size of the first axial spline tooth set to be the same as the shape and size of the standard spline interface, further improving the compatibility of electric bicycle parts and reducing manufacturing and assembly costs.

[0044] In addition, such as Figure 1 As shown in Figure 3, an annular boss 104 is provided at the end of the first shaft 1 away from the left shaft cup 5; correspondingly, an annular groove 302 is provided inside the second shaft 3 near the fifth spline tooth 301 to engage with the annular boss 104. After assembly, the annular boss 104 is embedded in the annular groove 302. The engagement of the boss and the annular groove ensures the concentricity of the first shaft 1 and the second shaft 3, which is beneficial to improving the stability of the sensor's torque signal and the service life of the shafts and related accessories.

[0045] For example Figure 1 As shown in Figure 3, a first limiting part 105 is provided inside the third spline tooth 102, and a second limiting part 305 is provided inside the fifth spline tooth 301. The first limiting part 105 and the second limiting part 305 are engaged. The beneficial technical effect of this structure is that the first limiting part 105 determines the relative angle of the first shaft 1, and the second limiting part determines the relative angle of the second shaft 3, thereby ensuring that the spline tooth profile of the first shaft 1 and the second shaft 3 is radially aligned after assembly, ultimately ensuring that the left and right cranks are aligned 180 degrees after being assembled onto the first and second shafts. Additionally, it can prevent misalignment between the third spline tooth 102 and the fifth spline tooth 301, reducing assembly difficulty and manufacturing costs.

[0046] like Figure 2 As shown, the axis of the first axle 1 includes a hollow space 109. High-end electric-assist bicycles have high requirements for overall lightness, and by setting the hollow space 109, the weight of the axle is reduced.

[0047] like Figure 1 , Figure 2As shown, an elastic pad is provided at the splined interface between the first shaft 1 and the torque sensor 3, or at the interface between the second shaft 2 and the torque sensor 3, or at the interface between the inner diameter of the torque sensor 3 and the outer diameter of the second shaft 2. In this example, an elastic pad 7 is provided at the interface between the first shaft 1 and the torque sensor 3, mainly to adjust the axial wobble caused by gaps in the production assembly or excessive axial tightness that affects the sensing of small torque signals of the sensor. An elastic pad 8, specifically an O-ring, is provided between the outer diameter of the second shaft 2 and the inner diameter of the right end of the torque sensor 3 to adjust the concentricity of the outer diameter of the second shaft 2 and the torque sensor 3, so as to meet the sensor's finer signal sensing requirements. The elastic pads 7 and 8 can be annular washers or O-rings with a circular cross-section, and the material can be rubber rings or polymer elastic materials. The provision of elastic pads 7 and 8 helps to improve the tightness and firmness of the shaft structure assembly and the sensing of sensor signals. More importantly, elastic pads 7 are provided at the interface between the first roller 1 and the torque sensor 3, and at the interface between the second roller 2 and the torque sensor 3. An elastic pad 8 is provided between the outer diameter of the second roller 2 and the inner diameter of the right end of the torque sensor 3. The elastic pad 8 can enable the torque sensor 3 to sense smaller and more subtle pedaling torque signals, thereby enabling the power controller to provide more accurate power assist control. The structural principle is as follows: the first shaft 1, the second shaft 3, and the torque sensor 3 are connected axially by the axial bolt 4 and the internal threaded hole to provide axial pressure and mutual resistance. The left crank twists the first shaft 1 through the first spline tooth at the left end of the shaft, and transmits the torque signal to the torque sensor 3 through the second spline tooth 101 and the fourth spline tooth 201. The right crank twists the second shaft 3 through the first spline tooth at the right end of the shaft. The second shaft 3 twists the first shaft 1 through the cooperation of the third spline tooth 102 and the fifth spline tooth 301. The first shaft 1 transmits the torque signal to the torque sensor 3 through the second spline tooth 101 and the fourth spline tooth 201, thereby realizing the torque sensor 3 sensing the torque of the left and right cranks. Without the elastic pads 7 and 8, at the interface between the first shaft 1 and the torque sensor 3 or the interface between the second shaft 2 and the torque sensor 3, because they are rigidly connected in the axial direction or the outer diameter of the second shaft 2 and the inner diameter of the right end of the torque sensor 3 are tightly fitted in the axial direction, there is a huge instantaneous frictional force between the interface between the first shaft 1 and the torque sensor 3 or the interface between the second shaft 2 and the torque sensor 3, and the outer diameter of the second shaft 2 and the inner diameter of the right end of the torque sensor 3. The torque transmitted from the left and right cranks must first overcome this instantaneous frictional force before it can be sensed by the torque sensor 3. Therefore, slight pedaling torque will not be sensed by the torque sensor 3.After adding the elastic pad at the above interface, since the elastic pad isolates the direct rigid contact in the axial direction, and the elastic pad has elastic deformation in the circumferential direction and end face of the shaft, the torque transmitted from the left and right cranks can be sensed more directly by the torque sensor 3.

[0048] In addition, the torque sensor 2 of this invention has, from left to right, a sixth spline tooth that engages with the axial spline teeth on the inner wall of the center hole of the bottom bracket of an electric bicycle, and a thread that engages with the locking nut thread, the sixth spline tooth extending out of the bottom bracket tube. It also includes a locking nut 9; the locking nut 9 is fixed to the external thread of the end of the torque sensor 2 furthest from the left axle cup 5 via its inner wall thread. This structure improves the stability of the axle assembly structure and makes it more compatible with the torque sensor in the bottom bracket tube of a bicycle, further enhancing the versatility of the parts.

[0049] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications or equivalent substitutions made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A shaft stick structure adapting the interface of five-way pipe and spline tooth of the middle shaft of bicycle, comprising left shaft bowl (5), right shaft bowl (6), torque sensor (2); the torque sensor (2) is hollow cylindrical structure; the left shaft bowl (5) and right shaft bowl (6) are respectively provided with threads matched with the inner wall threads of five-way pipe; characterized in that, Also include: The first shaft stick (1), the second shaft stick (3) and the axial bolt (4); The first shaft stick (1) is close to the outer edge of the end of the left shaft bowl (5) and the outer edge of the end of the second shaft stick (3) close to the right shaft bowl (6) is provided with the first spline tooth which is embedded with the crank interface spline tooth of the pedal; The outer edge of the middle of the first shaft stick (1) is provided with the second spline tooth (101); The outer edge of the end of the first shaft stick (1) away from the left shaft bowl (5) is provided with the third spline tooth (102), and the end is provided with an internal thread hole along the axial direction; The end of the torque sensor (2) close to the left shaft bowl (5) is provided with the fourth spline tooth (201) matched with the second spline tooth; The second shaft stick (3) is a hollow column structure; The end of the second shaft stick (3) close to the left shaft bowl (5) is provided with the fifth spline tooth (301) matched with the third spline tooth (102), and the inner wall of the end of the second shaft stick (3) close to the right shaft bowl (6) is provided with the boss (304); The axial bolt (4) is provided with an external thread matched with the internal thread hole; The axial bolt (4) passes through the axial hole of the second shaft stick (3) and is combined with the first shaft stick (1), and the nut of the axial bolt (4) abuts against the boss (304).

2. A hub collar structure for adapting a five- way tube to a sprocket tooth interface of a bicycle chain, according to claim 1, wherein, The shape and size of the first spline tooth are the same as those of the spline tooth standard interface.

3. A hub collar structure for adapting a five- way tube to a sprocket tooth interface of a bicycle chain, according to claim 1, wherein, The end of the first shaft stick (1) away from the left shaft bowl (5) is provided with an annular boss (104); The inside of the second shaft stick (3) is provided with an annular groove (302) embedded with the annular boss (104) adjacent to the fifth spline tooth (301).

4. A hub collar structure for adapting a five- way tube to a sprocket tooth interface of a bicycle chain, according to claim 1, wherein, The third spline tooth (102) is provided with a first limiting part (105), and the fifth spline tooth (301) is provided with a second limiting part (305), and the first limiting part (105) is embedded with the second limiting part (305).

5. A hub collar structure for adapting a five- way tube to spline tooth interface of a bicycle chainring according to claim 1, wherein, The axis of the first shaft stick (1) includes a hollow space.

6. A hub collar structure for adapting a five- way tube to spline tooth interface of a bicycle chainring, according to claim 1, wherein, An elastic pad (8) is arranged at the spline tooth interface of the first shaft stick (1) and the torque sensor (2), or the interface of the second shaft stick (3) and the torque sensor (2), or the interface of the inner diameter of the torque sensor (2) and the outer diameter of the second shaft stick (3).

7. A hub collar structure for adapting a five- way tube to spline tooth interface of a bicycle chainring, according to claim 1, wherein, The outer edge radius of the left part of the first spline tooth of the first shaft stick (1) is greater than the inner diameter of the left end of the torque sensor (2); The outer diameter of the right end of the second shaft stick (3) is greater than the inner diameter of the right end of the torque sensor (2).

8. A hub collar structure for adapting a five- way tube to spline tooth interface of a bicycle chainring, according to claim 1, wherein, The torque sensor (2) is provided with a sixth spline tooth embedded with the axial spline tooth of the central hole inner wall of the central shaft tooth disc of the electric bicycle from left to right at the outer edge of the end of the torque sensor (2) away from the left shaft bowl (5), and an external thread matched with the locking nut thread, and the sixth spline tooth protrudes out of the five-way pipe.

9. A hub collar structure for adapting a five- way tube to spline tooth interface of a bicycle chainring, according to claim 8, wherein, It also includes a locking nut (9); The locking nut (9) is connected and fixed with the external thread of the end of the torque sensor (2) away from the left shaft bowl (5) through the inner wall thread.

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