Torque sensor device and power-assisted bicycle

Abstract

The utility model relates to a torque sensor device and a power-assisted bicycle, and the torque sensor device comprises a five-way assembly which comprises a bearing sleeve which is provided with a first sleeving part; the first bearing is arranged in the first sleeving part in a sleeving mode, the middle shaft is arranged in an inner ring of the first bearing in a penetrating mode, and the middle shaft can rotate around an axis relative to the first sleeving part through the first bearing; the strain gauge is arranged in the radial direction of the middle shaft, a part of the peripheral surface of the first sleeving part is cut to form a cutting surface, and the strain gauge is arranged on the cutting surface; when the center shaft rotates around the axis, radial pressure can be applied to the cutting portion, with the cutting face, of the first sleeving portion through the first bearing, the cutting portion can deform in the tangential direction perpendicular to the radial direction, and the strain gauge can deform along with deformation of the cutting portion.

Description

Technical Field

[0001] This utility model relates to the field of bicycle technology, and in particular to a torque sensor device and an electric bicycle. Background Technology

[0002] An electric bicycle is a new type of vehicle that uses batteries as an auxiliary power source, is equipped with a motor, and has a power assistance system, enabling both human-powered riding and motor-assisted riding to be integrated.

[0003] As a core component of electric bicycles, the torque sensor can sense the pedaling torque and cadence of the bicycle in real time, and use this as the input signal for the electric assist system. This allows the system to output electric assist power that is strictly proportional to the rider's pedaling power at high speed, achieving an easy and effortless riding experience where the bike moves as you wish.

[0004] In traditional technology, torque sensors require the sensing device to be mounted on the central shaft. Since the central shaft is a rotating component, the sensing device needs to be connected to the main control circuit wirelessly, resulting in a complex structure and high cost. Utility Model Content

[0005] Therefore, it is necessary to provide a torque sensor device and an electric bicycle that can improve upon the above problems.

[0006] A torque sensor device, comprising:

[0007] The five-way connector assembly includes a bearing sleeve, the bearing sleeve having a first fitting portion;

[0008] A first bearing and a central shaft, wherein the first bearing is sleeved in the first sleeve portion, and the central shaft passes through the inner ring of the first bearing, and the central shaft can rotate relative to the first sleeve portion about an axis via the first bearing;

[0009] The strain gauge is mounted on the cut surface formed by cutting a portion of the outer peripheral surface of the first sleeve portion in the radial direction of the central axis.

[0010] When the central shaft rotates around the axis, it can apply radial pressure to the cut portion with the cut surface of the first sleeve through the first bearing. The cut portion can deform in the tangential direction perpendicular to the radial direction, and the strain gauge can deform along with the cut portion.

[0011] In one embodiment, the shape of the cut surface is adapted to the shape of the strain gauge.

[0012] In one embodiment, the torque sensor device further includes an adhesive element through which the strain gauge is bonded to the cut surface.

[0013] In one embodiment, the bearing sleeve further includes a second sleeve portion that is axially connected to the first sleeve portion on the central shaft, and the central shaft is sleeved within the second sleeve portion;

[0014] The torque sensor device also includes a circuit board, which is mounted on the outer peripheral surface of the second sleeve, and the strain gauge is electrically connected to the circuit board via a wire.

[0015] In one embodiment, the strain gauge has a welded protrusion, and the wire is welded to the welded protrusion.

[0016] In one embodiment, the bearing sleeve further includes a third sleeve portion, which is axially disposed between the first sleeve portion and the second sleeve portion on the central shaft, and the outer diameter of the third sleeve portion is smaller than the outer diameters of the first sleeve portion and the second sleeve portion.

[0017] The first sleeve, the third sleeve, and the second sleeve together form a receiving groove, and the wire is received in the receiving groove.

[0018] In one embodiment, the torque sensor further includes a Hall effect device and a magnetic ring. The Hall effect device is mounted on the circuit board, and the magnetic ring is sleeved on the central axis. The Hall effect device and the magnetic ring cooperate to detect the pedaling frequency of the central axis.

[0019] In one embodiment, the bottom bracket assembly further includes a first bowl assembly and a bottom bracket pipe, wherein the first bowl assembly is disposed inside the bottom bracket pipe;

[0020] The first sleeve is supported inside the first bowl assembly, and the strain gauge is located inside the first bowl assembly and has a gap with the inner wall of the first bowl assembly.

[0021] In one embodiment, the bottom bracket assembly further includes a second cup assembly and a second bearing. The second cup assembly is disposed inside the bottom bracket tube and is spaced apart from the first cup assembly in the axial direction of the central shaft. The second bearing is supported inside the second cup assembly, and the central shaft passes through the inner ring of the second bearing.

[0022] The end of the bearing sleeve away from the first bearing extends into the second cup assembly.

[0023] An electric bicycle includes a chainring, cranks, a freewheel, a chain, and a torque sensor device as described above, wherein the chainring and the cranks are both connected to the bottom bracket, and the chain is disposed on the chainring and the freewheel.

[0024] In the aforementioned torque sensor device and power-assisted bicycle, the strain gauge is located on the cut surface of the bearing sleeve, rather than being directly attached to the bottom bracket. The movement of the bottom bracket is transmitted to the strain gauge through the first bearing and the cut surface. In this way, the torque sensor device can be connected to the main control circuit in a wired manner. While ensuring the simplicity of the torque sensor device structure, it also reduces production costs compared to the wireless method. Attached Figure Description

[0025] Figure 1 An isometric view of a torque sensor device provided in an embodiment of this application;

[0026] Figure 2 for Figure 1 Axonometric view of a portion of the torque sensor device shown;

[0027] Figure 3 for Figure 1 Side view of the torque sensor device shown;

[0028] Figure 4 for Figure 3 A cross-sectional view of the torque sensor device shown in section AA;

[0029] Figure 5 for Figure 4 A BB-plane cross-sectional view of the torque sensor device shown;

[0030] Figure 6 for Figure 1 Axonometric view of a portion of the torque sensor device shown;

[0031] Figure 7 for Figure 4 The torque sensor device shown is a cross-sectional view of the C-plane.

[0032] Explanation of reference numerals in the attached figures:

[0033] 100. Torque sensor device; 10. Five-way assembly; 11. Bearing sleeve; 111. First fitting part; 112. Cutting surface; 113. Cutting part; 114. Second fitting part; 115. Third fitting part; 116. Receiving groove; 117. Fourth fitting part; 12. First cup assembly; 13. Five-way pipe; 14. Second cup assembly; 20. First bearing; 30. Central shaft; 40. Strain gauge; 41. Welded protrusion; 50. Circuit board; 60. Hall effect device; 70. Magnetic ring; 80. Second bearing; 90. Wire. Detailed Implementation

[0034] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0035] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0036] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0037] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0038] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0039] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0040] See Figure 1 and Figure 2 This application provides an embodiment of an electric bicycle, including a torque sensor device 100, a chainring, cranks, a freewheel, and a chain. The torque sensor device 100 includes a bottom bracket assembly 10, a first bearing 20, and a bottom bracket 30. The bottom bracket assembly 10 includes a bearing sleeve 11, which has a first fitting portion 111. The first bearing 20 is fitted inside the first fitting portion 111, and the bottom bracket 30 passes through the inner ring of the first bearing 20. The bottom bracket 30 is rotatable relative to the first fitting portion 111 via a first axis. The chainring and cranks are both connected to the bottom bracket 30, and the chain is mounted on the chainring and freewheel.

[0041] With the above setup, the rider's pedaling torque tensions the chain between the chainring and the freewheel via the crank, and enables the bottom bracket 30 to generate a force component and displacement in the first direction (one of the radial directions of the bottom bracket 30, approximately parallel to the line connecting the bottom bracket and the rear axle). The torque detection component of the electric-assisted bicycle (described below) detects the pedaling frequency and cadence, which serve as input signals for the electric-assisted system, enabling the system to output electric-assisted power that is strictly proportional to the rider's pedaling power at high speed, achieving the goal of easy and effortless pedaling.

[0042] Continue reading Figure 2 The torque sensor device 100 also includes a strain gauge 40. In the radial direction of the central axis 30, a portion of the outer peripheral surface of the first housing 111 is cut to form a cut surface 112, and the strain gauge 40 is mounted on the cut surface 112. (See reference...) Figures 3-5When the central shaft 30 rotates around its axis, due to the force component and displacement in the first direction, the central shaft 30 can apply radial pressure to the cut portion 113 with the cut surface 112 of the first sleeve portion 111 through the first bearing 20. The cut portion 113 can deform in the tangential direction perpendicular to the radial direction, and the strain gauge 40 can deform along with the cut portion 113. Optionally, the strain gauge 40 is a bridge strain gauge. The bridge strain gauge utilizes the small deformation of the metal sheet under external force to change the resistance value, which is converted into a voltage change through a bridging circuit to measure strain. It is understood that in some other embodiments, the type of strain gauge 40 is not limited, as long as it can generate deformation and transmit signals to the circuit board 50 to measure the pedaling frequency and cadence.

[0043] It should be noted that the portion of the first set 111 with the cutting surface 112 forms the cutting portion 113. It should also be noted that radial pressure is the same as normal pressure (radial pressure along...). Figure 5 (in the direction of the left arrow), when the cut portion 113 is subjected to radial pressure, because the cut portion 113 is relatively thin, it can extend and deform to both sides in the circumferential direction of the bearing sleeve 11 (the cut portion 113 along...). Figure 5 (Deformation extending in the direction of the up and down arrows). Since the strain gauge 40 is mounted on the cutting surface 112, the strain gauge 40 can deform in accordance with the deformation of the cutting part 113.

[0044] The torque sensor device 100 provided in this application embodiment has a strain gauge 40 disposed on the cut surface 112 of the bearing sleeve 11, rather than being directly attached to the central shaft 30. The movement of the central shaft 30 is transmitted to the strain gauge 40 through the first bearing 20 and the cut part 113. In this way, the torque sensor device 100 can be connected to the main control circuit in a wired manner. While ensuring the simplicity of the structure of the torque sensor device 100, it also reduces the production cost compared to the wireless method.

[0045] In some embodiments, the shape of the cut surface 112 is adapted to the shape of the strain gauge 40. When the cut portion 113 is subjected to radial pressure, it can extend and deform to both sides in the circumferential direction of the bearing sleeve 11. Since the shape of the cut surface 112 is adapted to the shape of the strain gauge 40, the deformation of the cut portion 113 can be fully transmitted to the strain gauge 40 through the cut surface 112, so that the strain gauge 40 can deform along with the deformation of the cut portion 113.

[0046] In some embodiments, the strain gauge 40 has a flat plate structure, in which case the cutting surface 112 is a plane. In other embodiments, the strain gauge 40 has an arc-shaped curved structure, in which case the cutting surface 112 is a curved surface adapted to the shape of the strain gauge 40.

[0047] Furthermore, the torque sensor device 100 also includes an adhesive, through which the strain gauge 40 is bonded to the cut surface 112. Bonding the strain gauge 40 to the cut surface 112 using the adhesive is flexible, convenient, and secure. Of course, in other embodiments, the strain gauge 40 may also be fixed to the cut surface 112 in other ways, which are not limited here.

[0048] In some embodiments, see Figure 6 The bearing sleeve 11 also includes a second sleeve portion 114, which is axially disposed at one end of the first sleeve portion 111 on the central shaft 30, and is connected to the first sleeve portion 111. The central shaft 30 is sleeved within the second sleeve portion 114. (Continue reading) Figure 2 The torque sensor device 100 also includes a circuit board 50, which is mounted on the outer peripheral surface of the second sleeve 114. A strain gauge 40 is electrically connected to the circuit board 50 via a wire 90. The strain gauge 40 deforms, causing a change in its resistance value, and sends a signal to the circuit board 50 via the wire 90. The circuit board 50 processes and converts this signal into a voltage signal for the controller, which then powers the bicycle motor to output corresponding power, providing assistance proportional to the pedaling torque. The second sleeve 114 facilitates the installation and fixation of the circuit board 50.

[0049] Furthermore, the strain gauge 40 has a weld protrusion 41, and the wire 90 is welded to the weld protrusion 41 to facilitate the electrical connection between the wire 90 and the strain gauge 40.

[0050] Further reading Figure 6 The bearing sleeve 11 also includes a third sleeve portion 115, which is axially positioned between the first sleeve portion 111 and the second sleeve portion 114 along the central shaft 30. The outer diameter of the third sleeve portion 115 is smaller than the outer diameters of the first sleeve portion 111 and the second sleeve portion 114. The first sleeve portion 111, the second sleeve portion 114, and the third sleeve portion 115 together form a receiving groove 116, into which the wire 90 is received. Specifically, the wire 90 has a first connecting portion, a middle portion, and a second connecting portion. The first connecting portion is connected to the circuit board 50, the second connecting portion is connected to the strain gauge 40, and the middle portion is received in the receiving groove 116. This arrangement ensures that the wire 90 is neatly arranged.

[0051] See Figure 7The torque sensor device 100 also includes a Hall effect device 60 and a magnetic ring 70. The Hall effect device 60 is mounted on the circuit board 50, and the magnetic ring 70 is sleeved on the central axle 30. The Hall effect device 60 and the magnetic ring 70 cooperate to detect the pedaling frequency of the central axle 30. Specifically, the second sleeve portion 114 has a through hole, through which the Hall effect device 60 passes into the interior of the bearing sleeve 11 to cooperate with the magnetic ring 70 in detecting the pedaling frequency of the central axle 30. The Hall effect device 60 is a magnetic sensor based on the Hall effect. It can detect changes in the magnetic field of the magnetic ring 70 and convert them into electrical signals to detect the pedaling frequency of the central axle 30. The signal is then sent to the circuit board 50, processed by the circuit board 50, and sent to the controller. The motor of the electric bicycle can then output a corresponding frequency, providing assistance proportional to the pedaling frequency.

[0052] Continue reading Figure 4 The five-way assembly 10 also includes a first cup group 12 and a five-way pipe 13, with the first cup group 12 disposed within the five-way pipe 13. A first sleeve part 111 is supported within the first cup group 12, and the strain gauge 40 is located within the first cup group 12, with a gap between it and the inner wall of the first cup group 12. In this way, the first cup group 12 serves to support the bearing sleeve 11, and the arrangement of the first cup group 12 does not hinder the strain gauge 40 from generating strain.

[0053] Furthermore, the bottom bracket assembly 10 also includes a second cup arm 14 and a second bearing 80. The second cup arm 14 is disposed within the bottom bracket tube 13 and is spaced apart from the first cup arm 12 axially from the central shaft 30. The second bearing 80 is supported within the second cup arm 14, and the central shaft 30 passes through the inner ring of the second bearing 80. The end of the bearing sleeve 11 away from the first bearing 20 extends into the second cup arm 14. Specifically, the bearing sleeve 11 includes a fourth fitting portion 117, which is connected to the end of the second fitting portion 114 away from the third fitting portion 115. A portion of the fourth fitting portion 117 extends into the second cup arm 14. In this way, the central shaft 30 rotates relative to the bottom bracket assembly 10 via the first bearing 20 and the second bearing 80. The first bearing 20 and the second bearing 80 jointly support the central shaft 30, ensuring the smooth rotation of the central shaft 30. At the same time, since part of the fourth assembly 117 extends into the second bowl assembly 14, the probability of dust entering the second bearing 80 through the second bowl assembly 14 is reduced.

[0054] Another embodiment of this application also provides a torque sensor device 100 included in the above-described power-assisted bicycle. Since the power-assisted bicycle has beneficial effects, the torque sensor device 100 has the same beneficial effects, and will not be described in detail here.

[0055] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0056] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A torque sensor device, characterized in that, include: The five-way assembly (10) includes a bearing sleeve (11) having a first fitting portion (111); The first bearing (20) and the central shaft (30) are fitted inside the first sleeve part (111). The central shaft (30) passes through the inner ring of the first bearing (20). The central shaft (30) can rotate relative to the first sleeve part (111) about an axis through the first bearing (20). The strain gauge (40) is mounted on the cut surface (112) formed by cutting a portion of the outer peripheral surface of the first sleeve part (111) in the radial direction of the central axis (30). When the central shaft (30) rotates around the axis, it can apply radial pressure to the cutting part (113) with the cutting surface (112) of the first sleeve (111) through the first bearing (20). The cutting part (113) can deform in the tangential direction perpendicular to the radial direction, and the strain gauge (40) can deform along with the cutting part (113).

2. The torque sensor device according to claim 1, characterized in that, The shape of the cut surface (112) is adapted to the shape of the strain gauge (40).

3. The torque sensor device according to claim 1, characterized in that, The torque sensor device also includes an adhesive, through which the strain gauge (40) is bonded to the cut surface (112).

4. The torque sensor device according to claim 1, characterized in that, The bearing sleeve (11) further includes a second sleeve (114) that is axially connected to the first sleeve (111) on the central shaft (30), and the central shaft (30) is sleeved in the second sleeve (114); The torque sensor device also includes a circuit board (50), which is mounted on the outer peripheral surface of the second sleeve (114), and the strain gauge (40) is electrically connected to the circuit board (50) via a wire (90).

5. The torque sensor device according to claim 4, characterized in that, The strain gauge (40) has a welded protrusion (41), and the wire (90) is welded to the welded protrusion (41).

6. The torque sensor device according to claim 4, characterized in that, The bearing sleeve (11) further includes a third sleeve portion (115), which is axially disposed between the first sleeve portion (111) and the second sleeve portion (114) on the central shaft (30). The outer diameter of the third sleeve portion (115) is smaller than the outer diameters of the first sleeve portion (111) and the second sleeve portion (114). The first sleeve (111), the third sleeve (115) and the second sleeve (114) together form a receiving groove (116), and the wire (90) is received in the receiving groove (116).

7. The torque sensor device according to claim 4, characterized in that, The torque sensor also includes a Hall effect device (60) and a magnetic ring (70). The Hall effect device (60) is mounted on the circuit board (50), and the magnetic ring (70) is sleeved on the central shaft (30). The Hall effect device (60) and the magnetic ring (70) cooperate to detect the pedaling frequency of the central shaft (30).

8. The torque sensor device according to claim 1, characterized in that, The five-way assembly (10) further includes a first bowl assembly (12) and a five-way pipe (13), wherein the first bowl assembly (12) is disposed inside the five-way pipe (13); The first sleeve (111) is supported inside the first bowl assembly (12), and the strain gauge (40) is located inside the first bowl assembly (12) and has a gap with the inner wall of the first bowl assembly (12).

9. The torque sensor device according to claim 8, characterized in that, The five-way assembly (10) further includes a second cup group (14) and a second bearing (80). The second cup group (14) is disposed inside the five-way tube (13) and is spaced apart from the first cup group (12) in the axial direction of the central shaft (30). The second bearing (80) is supported inside the second cup group (14), and the central shaft (30) passes through the inner ring of the second bearing (80). The end of the bearing sleeve (11) away from the first bearing (20) extends into the second cup assembly (14).

10. A power-assisted bicycle, characterized in that, It includes a chainring, a crank, a freewheel, a chain, and a torque sensor device as described in any one of claims 1-9, wherein the chainring and the crank are both connected to the central shaft (30), and the chain is disposed on the chainring and the freewheel.

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