CN220122718U - Hub motor - Google Patents

Abstract

The utility model provides a hub motor, which is suitable for being mounted on a bicycle, comprising: spindle, stator, rotor, housing, sleeve and torque sensor. The hub motor is secured to a frame of the bicycle by a spindle, and the stator is secured to the spindle and includes an electromagnet. The rotor is rotatably sleeved on the mandrel and is suitable for rotating around the stator. The shell is rotatably sleeved on the mandrel and is suitable for rotating around the rotor and the mandrel, the shell is provided with a containing space, a first perforation, an opening and a side cover, the side cover is provided with a second perforation, and the mandrel is respectively penetrated through the shell and the side cover through the first perforation and the second perforation. The sleeve is sleeved on the mandrel and connected to the side cover. The sleeve has a setting portion located on a side surface of the sleeve remote from the spindle. The torque sensor is connected with the sleeve and provided with a sensing unit, and the sensing unit is arranged at the setting part.

Description

Hub motor

Technical Field

The present utility model relates to a motor, and more particularly to a hub motor for a bicycle.

Background

A bicycle is a manually driven vehicle with a history of more than a hundred years. Recently, in order to assist a rider, a part of bicycles are equipped with a hub motor as an auxiliary power for propulsion. A Hub motor (Hub motor) is a motor that drives a housing to rotate through an internal mechanism, and can be mounted on a front wheel or a rear wheel of a bicycle to drive the front wheel or the rear wheel of the bicycle as auxiliary power of the bicycle.

As auxiliary power, many hub motors of bicycles are used with torque sensors coupled to a transmission assembly of the bicycle, and once the torque sensor senses that the torque input by the rider is greater than a certain value, the hub motor is started. Among them, how to accurately sense the torque input by the rider is a challenge because of the complex use environment.

Disclosure of Invention

The utility model aims to provide a hub motor with good sensing performance.

To achieve the above advantages, one embodiment of the present utility model provides a hub motor adapted to be mounted on a bicycle, comprising: spindle, stator, rotor, housing, sleeve and torque sensor. The spindle is secured to a frame of the bicycle and has a first end and an opposite second end. A stator is secured to the mandrel proximate the first end, the stator including an electromagnet. The rotor is rotatably sleeved on the mandrel and is suitable for rotating around the stator. The shell is rotatably sleeved on the mandrel and is suitable for rotating around the rotor and the mandrel, the shell is provided with a containing space, a first perforation, an opening and a side cover, the side cover is used for closing the opening and is provided with a second perforation, the containing space contains the stator and the rotor, the opening faces the second end, and the mandrel is respectively penetrated through the shell and the side cover through the first perforation and the second perforation. The sleeve is sleeved at the second end of the mandrel and connected to the side cover, and is provided with a setting part, and the setting part is positioned on one side surface of the sleeve away from the mandrel. The torque sensor is connected with the sleeve and provided with a sensing unit, and the sensing unit is arranged at the setting part.

In an embodiment, the sensing unit is spaced from the axis of the spindle by 8.15 mm-12.6 mm.

In an embodiment, the hub motor further includes an outer cylinder sleeved on the sleeve and covering the setting portion and the torque sensor.

In one embodiment, the sleeve and the outer cylinder together form an internal ratchet mechanism.

In one embodiment, the outer cylinder is adapted to engage a gear set of a bicycle.

In an embodiment, the sensing unit is a strain gauge, and a sensing direction of the strain gauge is along a circumferential direction of the sleeve.

In an embodiment, the hub motor further includes a power supply mechanism electrically connected to the torque sensor and including a first coil and a second coil, wherein the first coil is electrically connected to the power supply and fixed on the spindle, the second coil is fixed on the sleeve and parallel to the first coil and is adapted to rotate relative to the first coil, and the torque sensor is electrically connected to the second coil and is electrically connected to the power supply through the first coil and the second coil.

As described above, the hub motor of the present utility model has a good sensing performance because the sensing unit of the torque sensor is mounted on the side surface of the sleeve away from the spindle, and thus water or dirt entering the gap between the spindle and the sleeve can be shielded by the sleeve, preventing the sensing unit of the torque sensor from being affected.

Other features and embodiments of the present utility model are described in detail below with reference to the following drawings.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present utility model, and other drawings may be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1A is an exploded view of a hub motor according to an embodiment of the present utility model;

FIG. 1B is an exploded view of the hub motor of FIG. 1A at another angle;

FIG. 2 is a schematic cross-sectional view of the hub motor of FIG. 1A;

FIG. 3 is a schematic perspective view of the sleeve of FIG. 2;

FIG. 4 is a schematic cross-sectional view of the torque sensor of FIG. 2 at the location of its installation;

fig. 5 is a schematic cross-sectional view of the sleeve of fig. 2 at the location of the inscribed ratchet mechanism.

Symbol description

1: hub motor 2: mandrel

21: center shaft member 22: connecting piece

221: center post 221a: channel(s)

222: positioning disk 2A: first end

2B: second end 3: stator

31: electromagnet 32: control unit

4: rotor 5: outer casing

501: hole 5A: body

502: opening 503: first perforation

5B: side cover 504: second perforation

505: fourth perforation 6: ratchet seat

51a, 51b, 51c, 51d: rolling bearing

61: sleeve 61A: first section

61B: second section 61C: third section

61D: fourth section 61E: fifth section

611: slide cover 611a: first substrate

611b: power supply line 611c: second substrate

612a: first disk 612b: second tray body

612c: third disk 613: third perforation

614: first receiving groove 615: setting part

616: second receiving groove 616a: an opening

616b: collar 617: third storage groove

617a: groove 618: pulling piece

618a: positioning end 618b: pushing end

619: fourth receiving groove 62: outer cylinder

621: rib 622: internal ratchet wheel

7: torque sensor 71: sensing unit

72: the third substrate 73: fourth substrate

8: power cord 9: planetary gear set

91: sun gear 92: transmission assembly

93: toothed ring S1: accommodating space

S2: cavity D1: direction of extension

D2: radial direction D3: in the circumferential direction

D4: gravity direction d: spacing of

A: the axis P: power supply mechanism

Detailed Description

In the following articles, for the terms used in the description of the embodiments according to the present utility model, for example: the description of the orientation or positional relationship indicated by the terms "upper" and "lower" are based on the orientation or positional relationship shown in the drawings used, and the terms are merely for convenience of description of the present utility model, and are not meant to limit the present utility model, i.e., the components mentioned are not necessarily oriented or implied to have a particular orientation or configuration. In addition, the terms "first," "second," and the like in the description and in the claims are used for naming components (elements) or distinguishing between different embodiments or ranges, and are not used for limiting the upper or lower limit of the number of components.

Fig. 1A is an exploded view of a hub motor according to an embodiment of the present utility model. FIG. 1B is an exploded view of the hub motor of FIG. 1A at another angle. FIG. 2 is a schematic cross-sectional view of the hub motor of FIG. 1A. As shown in fig. 1A to 2, the hub motor 1 of the present embodiment is adapted to be mounted on a bicycle (not shown). The hub motor 1 includes: spindle 2, stator 3, rotor 4, housing 5, sleeve 61 and torque sensor 7. The spindle 2 is fixed to a frame (not shown) of a bicycle and has a first end 2A and an opposite second end 2B (see the figure) in an extension direction D1. A stator 3 is fixed to the spindle 2, close to the first end 2A, the stator 3 comprising an electromagnet 31. The rotor 4 is rotatably fitted over the spindle 2 and is adapted to rotate about the stator 3. The housing 5 is rotatably sleeved on the spindle 2 and is adapted to rotate around the rotor 4 and the spindle 2. The housing 5 is formed with a receiving space S1, an opening 502, a first perforation 503, and a side cover 5B. The side cover 5B is used for closing the opening 502 and is provided with a second through hole 504. The accommodating space S1 accommodates the stator 3 and the rotor 4, the opening 502 faces the second end 2B, and the spindle 2 is respectively inserted into the housing 5 and the side cover 5B through the first through hole 503 and the second through hole 504. The sleeve 61 is fitted over the second end 2B of the spindle 2 and connected to the side cover 5B, and the sleeve 61 has a setting portion 615, the setting portion 615 being located on a side surface of the sleeve 61 remote from the spindle 2. The torque sensor 7 is connected to the sleeve 61. The torque sensor 7 has a sensing unit 71. The sensing unit 71 is disposed at the setting portion 615. The hub motor 1 is started, for example, after the torque sensed by the torque sensor 7 is greater than a preset value, so as to be used as auxiliary power of the bicycle.

In the present embodiment, the hub motor 1 is, for example, mounted to a rear wheel (not shown) of a bicycle, and the spindle 2 is, for example, fixed to a frame of the bicycle. The housing 5 includes, for example, a body 5A and a side cover 5B, the accommodating space S1 is located in the body 5A, and the first through hole 503 and the opening 502 are located at a side of the body 5A near the first end 2A and a side near the second end 2B, respectively. The outer surface of the body 5A has a plurality of holes 501, and the holes 501 are adapted to connect with a plurality of spokes (spokes) to indirectly connect with a rim (not shown) of a rear wheel of the bicycle, so as to rotate the rear wheel when the body 5 rotates. The mounting position of the hub motor 1 is not limited to the rear wheel.

As shown in fig. 1A to 2, in the present embodiment, the stator 3 includes, for example, an electromagnet assembly 31 (a combination of a plurality of electromagnets). The electromagnet assembly 31 is fixed on the spindle 2 and generates a magnetic field by means of the current supplied from the power line 8, so that the rotor 4, for example comprising magnets, rotates with respect to the stator 3, and then the whole housing 5 is rotated by means of the rotor 4 and the planetary gear set 9.

The hub motor 1 controls the magnitude of the current entering the electromagnet assembly 31 via the power cord 8, for example, by means of the control unit 32, to control the rotational speed of the housing 5 by varying the magnitude of the magnetic field generated by the electromagnet assembly 31. The position of the control unit 32 is not limited, for example, in the present embodiment, the control unit 32 is disposed at one side of the electromagnet assembly 31 as shown in fig. 1A and 2, and in another embodiment, the control unit 32 is disposed outside the hub motor 1.

As shown in fig. 1A to 2, in the present embodiment, the planetary gear set 9 includes, for example, a sun gear 91, a transmission assembly 92, and a ring gear 93. The sun gear 91 is for example connected to the rotor 4 and is adapted to rotate around the spindle 2 as the rotor 4 rotates. The transmission assembly 92 is connected between the sun gear 91 and the ring gear 93. The toothed ring 93 is tightly engaged with the body 5A, and is located at one side of the accommodating space S1 and close to the opening 502 (and the side cover 5B). When the rotor 4 rotates, the housing 5 can be rotated by the planetary gear set 9.

As shown in fig. 1A to 2, in the present embodiment, the mandrel 2 includes, for example, a central shaft 21 and a connecting member 22, and the connecting member 22 is near the first end 2A. The connecting piece 22 has a central post 221 (see fig. 1A and 2) and a positioning plate 222 (see fig. 2), the positioning plate 222 is located at one end of the central post 221 near the second end 2B of the mandrel 2, and is suitable for being connected with the stator 3, the central post 221 is suitable for being fixed on the mandrel 2, one end of the central post 221 away from the positioning plate 222 penetrates out of the body 5A from the first through hole 503 to be connected with the frame when being assembled, and a channel 221A for the power wire 8 to enter the accommodating space S1 from the first through hole 503 is formed. The central shaft 221 is sleeved with a rolling bearing 51a, and the rolling bearing 51a is suitable for contacting with the hole wall surface of the first through hole 503, so that the body 5A is rotatably sleeved on the central shaft 221 (mandrel 2). The detailed construction of the spindle 2 is not limited thereto.

As shown in fig. 1A to 2, in the present embodiment, the hub motor 1 further includes, for example, an outer cylinder 62. The outer tube 62 and the sleeve 61 together constitute the ratchet seat 6 of the hub motor 1. The outer cylinder 62 is rotatably fitted over the sleeve 61 and covers the outer diameter surface of the sleeve 61. The outer diameter of the outer barrel 62 is formed with a plurality of ribs 621 adapted to engage a chainring (not shown) of a gear change set of a bicycle. The inner diameter surface of the outer barrel 62 has an inner ratchet 622 (see fig. 1A). The outer tube 62 is adapted to constitute an internal ratchet mechanism (described in detail below) together with the dial 618 provided between the sleeve 61 and the outer tube 62 and the sleeve 61.

Fig. 3 is a perspective view of the sleeve of fig. 2. Fig. 4 is a schematic cross-sectional view of the torque sensor of fig. 2 at the location of installation. As shown in fig. 4, the sleeve 61 includes a first section 61A, a second section 61B, a third section 61C, a fourth section 61D, and a fifth section 61E in this order from the first end 2A to the second end 2B along the extending direction D1, for example.

As shown in fig. 1A, 3 and 4, the first section 61A of the sleeve 61 is rotatably coupled to the sliding cover 611. The slide cover 611 is fixed to the spindle 2 and rotatable relative to the sleeve 61 about the circumferential direction D3 of the sleeve 61, in other words, the slide cover 611 does not rotate together with the sleeve 61 when the housing 5 rotates. A cavity S2 is formed between the sliding cover 611 and the sleeve 61. A power supply mechanism P is arranged in the cavity S2. The power supply means is electrically connected to the torque sensor 7 and adapted to provide the current required by the torque sensor 7.

Specifically, as shown in fig. 3 and 4, the power feeding mechanism P in the present embodiment includes, for example: the first substrate 611a and the second substrate 611c. The first substrate 611a is fixed on the sliding cover 611, and has a first coil (not shown) and a power supply line 611b (see fig. 3) electrically connected to the first coil. The power supply line 611b is provided to penetrate the sliding cover 611 and is adapted to be connected to an external power source (not shown). The second base plate 611c is fixed to the sleeve 61 to be rotatable with respect to the first base plate 611a, and is spaced apart from the first base plate 611 a. The second substrate 611c has a second coil (not shown). When an external power source supplies current, the power supply mechanism P can generate an induced current through the first coil and the second wire section to be supplied to the torque sensor 7. The above description is merely an example, and the specific design of the power supply mechanism P is not limited to the above description.

As shown in fig. 2, 3 and 4, the second section 61B is adapted to be connected to the side cover 5B, and the first disk 612a, the second disk 612B and the third disk 612c protrude from the outer diameter surface of the second section 61B of the sleeve 61. Specifically, the first disc 612a, the second disc 612b and the third disc 612c extend from the outer diameter surface of the sleeve 61 along the radial direction D2, and the outer diameters of the first disc 612a, the second disc 612b and the third disc 612c are sequentially reduced. Wherein the outer diameter of the first disk 612a is larger than the diameter of the second perforation 504 on the side cover 5B. The outer diameter of the second disk 612b corresponds to the diameter of the second perforation 504. The outer diameter of the third disk 612c corresponds to the inner diameter of the outer cylinder 62 on the side near the first end 2A (see fig. 2).

As shown in fig. 2 and 3, the disk surface of the first disk 612a is provided with a plurality of third through holes 613 extending toward the extending direction D1, for example, the side cover 5B is provided with a plurality of fourth through holes 505, the fourth through holes 505 surround the second through holes 504, and the number and positions of the fourth through holes 505 correspond to those of the third through holes 613. In combination, the third through hole 613 and the fourth through hole 505 are aligned with each other by a plurality of screws, not shown, and the sleeve 61 is fixed to the side cover 5B. As shown in fig. 2 and 4, when the sleeve 61 is connected to the side cover 5B, the first disc 612a is located in the accommodating space S1. The second disk 612b, when assembled, covers the second perforation 504. The outer cylinder 62 is sleeved on the third disk 612c. In the present embodiment, the outer tube 62 is supported by the rolling bearing 51c and the rolling bearing 51d (described in detail later), for example, and therefore the sleeve 62 does not contact the third disk 612c, but the detailed connection relationship is not limited thereto.

As shown in fig. 2 and 4, the sleeve 61 has a first receiving groove 614 formed on an inner diameter surface of the second section 61B, and the first receiving groove 614 is used for receiving the rolling bearing 51B, and the rolling bearing 51B is, for example, a radial bearing, but not limited thereto. The sleeve 61 is supported on the spindle 2 by a rolling bearing 51 b. As can be seen from fig. 2, the position of the rolling bearing 51B in the extending direction D1 corresponds to the position of the side cover 5B. In other words, the rolling bearing 51B supports not only the sleeve 61 but also the side cover 5B (or the housing 5) indirectly on the spindle 2.

As shown in fig. 3 and 4, in the present embodiment, the installation portion 615 of the sleeve 61 is, for example, a ring groove that is located on the outer diameter surface of the third section 61C and is recessed along the radial direction D2 of the sleeve 61. The setting portion 615 is adapted to accommodate the sensing unit 71 of the torque sensor 7 and the third substrate 72 electrically connected to the sensing unit 71. As shown in fig. 4, when the sleeve 61 is combined with the outer tube 62, the outer tube 62 covers the setting portion 615, and the distance between the outer diameter surfaces of the second and fourth sections 61B and 61D and the spindle 2 is greater than the distance between the outer diameter surface of the third section 61C and the spindle 2. In other words, the sensing unit 71 is surrounded by the sleeve 61 and the outer cylinder 62, which is not easily disturbed by the external environment, so as to improve the measurement accuracy of the torque sensor 7.

As shown in fig. 3 and 4, in the present embodiment, the sensing unit 71 is, for example, two rectangular strain gauges (only one strain gauge is drawn due to the view angle), the strain gauges are connected to the surface of the installation portion 615, and the sensing direction of the strain gauges is, when the strain gauges are installed, the sensing direction of the strain gauges is, for example, the change of the sensing sleeve 61 along the circumferential direction D3, wherein, in the circumferential direction D3 of the sleeve 61, the two strain gauges are, for example, arranged symmetrically to the axis a of the sleeve 61, and, as shown in fig. 3, the two strain gauges are, for example, arranged at positions of 135 degrees and 315 degrees obliquely with respect to the gravitational direction D4, but the present utility model is not limited thereto. The third substrate 72 is, for example, semi-annular in shape corresponding to the shape of the installation portion 615, and two strain gauges (indicated by the sensing unit 71) are respectively connected along two ends of the sleeve 61 in the circumferential direction D3, and the detailed shape of the third substrate 72 can be changed according to the requirement. As shown in fig. 4, the sensing unit 71 has a distance d from the axis a of the spindle 2, and the distance d is, for example, between 8.15mm and 12.6mm, but not limited thereto.

Referring to fig. 4, the sleeve 61 has a second receiving groove 616 formed in an inner diameter surface of the third section 61C. The second receiving groove 616 is communicated with the cavity S2 from the inside of the sleeve 61, and the second receiving groove 616 is adapted to receive the fourth substrate 73 electrically connected to the third substrate 72. Specifically, the sleeve 61 has a passage (not shown) formed in the third section 61C, which communicates with the installation portion 615 and the second receiving groove 616 in the radial direction D2. The third substrate 72 of the torque sensor 7 may be connected to the fourth substrate 73 in the second receiving groove 616 through a passage, in other words, the size of the substrate of the torque sensor 7 (the sum of the third substrate 72 and the fourth plate 73 in the present embodiment) is increased. In addition, in the present embodiment, the sleeve 61 further has a collar 616b, the collar 616b is adapted to cover the opening 616a of the second receiving groove 616 near the mandrel 2, the collar 616b has an inner diameter corresponding to the inner diameters of the fourth segment 61D and the fifth segment 61E, and the collar 616b is used for protecting the fourth substrate 73.

Fig. 5 is a schematic cross-sectional view of the sleeve of fig. 2 at the location of the inscribed ratchet mechanism. As shown in fig. 3 and 5, the fourth section 61D of the sleeve 61 has, for example, three third receiving grooves 617 around the outer diameter surface of the sleeve 61 in the radial direction D2. Each of the third receiving grooves 617 is configured to receive one of the paddles 618, the paddles 618 has a positioning end 618a and a pushing end 618b, the positioning end 618a is swingably disposed in the third receiving groove 617, the pushing end 618b protrudes from the third receiving groove 617 along a radial direction D2 of the sleeve 61, for example, by an elastic member not shown, and is capable of contacting the inner ratchet 622 on an inner diameter surface of the outer cylinder 62, and the fourth segment 61D of the sleeve 61 is further provided with grooves 617a extending along a circumferential direction D3 of the sleeve 61 and passing through the third receiving grooves 617, but the detailed configuration of each component of the fourth segment 61D is not limited thereto.

The sleeve 61, the pulling piece 618 and the outer cylinder 62 are combined together to form an inscribed ratchet structure. The sleeve 61 is allowed to rotate relative to the outer tube 62 in one direction along the circumferential direction D3 of the spindle 2 and in the opposite direction by the action between the dial 618 and the inner ratchet 622 on the outer tube 62. The user of the bicycle can drive the sleeve 61 to rotate in one direction indirectly through a chain (not shown) and a fluted disc by stepping on pedals (not shown) of the bicycle, so as to drive the shell 5 of the hub motor 1 to rotate. And when the stator 3 inside the hub motor 1 is electrified and the rotating speed of the shell 5 exceeds the rotating speed of the shell 5 driven by the user, the sleeve 61 can independently rotate between the outer cylinder 62 and the sleeve 61 through the action of the inscribed ratchet 622 and the poking piece 618.

As can be seen from the above, the third section 61C provided with the sensing unit 71 is located between the second section 61B connected to the housing 5 and the fourth section 61D connected to the outer tube 62, so that when both ends of the sleeve 61 along the extending direction D1 are respectively affected by external forces from the second section 61B and the fourth section 61D, the sensing unit 71 (strain gauge) can change shape along the circumferential direction D3 to sense the torque input by the user.

Referring to fig. 2 to 4, in the fifth section 61E, a fourth receiving groove 619 is formed on an outer diameter surface of the sleeve 61, the opening direction of the fourth receiving groove 619 faces the outer cylinder 62, and the fourth receiving groove 619 is adapted to receive the rolling bearing 51c. When combined, this rolling bearing 51c contacts the inner wall surface of the outer tube 62, in other words, the sleeve 61 indirectly supports the outer tube 62 through the fifth segment 61E.

As shown in fig. 4, in the present embodiment, the outer tube 62 is supported by the rolling bearing 51d (described in detail below) installed between the outer tube 62 and the spindle 2 in addition to the rolling bearing 51c described in the preceding paragraph, and the rolling bearing 51c and the rolling bearing 51d are radial bearings, for example, but not limited thereto.

As shown in fig. 2 and 4, in the present embodiment, since the sensing unit 71 is attached to the outer diameter surface of the sleeve 61 and covered by the outer cylinder 62, the sensing unit 71 of the present embodiment has a larger radius distance (see the interval d in fig. 4 in detail) from the rotation axis of the spindle 2 than the sensing unit 71 is disposed in the second receiving groove 616, and has a higher sensing accuracy, and the periphery is protected by the outer cylinder 62 and the wall surface of the sleeve 61, so that the environmental impact can be avoided. In more detail, if fine dust runs into the gap between the spindle 2 and the sleeve 61 during operation, the sensing unit 71 is located on the outer diameter surface of the sleeve 61, so that the sensing unit 71 is protected by the wall surface of the sleeve 61 from the dust. Further, as is clear from fig. 4, since the rolling bearings 51c and 51D are provided so as to cover the gap between the outer diameter surface of the sleeve 61 and the inner diameter surface of the outer tube 62 in the extending direction D1, it is possible to prevent dust from entering from the gap and affecting the sensing unit 71.

As described above, the hub motor of the present utility model has a good sensing performance because the sensing unit of the torque sensor is mounted on the side surface of the sleeve away from the spindle, and thus water or dirt entering the gap between the spindle and the sleeve can be shielded by the sleeve, preventing the sensing unit of the torque sensor from being affected.

The above examples and/or embodiments are merely illustrative of preferred examples and/or embodiments for implementing the technology of the present utility model, and are not intended to limit the implementation of the technology of the present utility model in any way, and any person skilled in the art should consider that the technology or examples substantially identical to the technology or embodiments of the present utility model can be modified or altered slightly without departing from the scope of the technical means disclosed in the present disclosure.

Claims (7)

1. A hub motor adapted to be mounted to a bicycle, the hub motor comprising:

a spindle fixed on a frame of the bicycle and having a first end and an opposite second end;

a stator fixed on the mandrel and close to the first end, the stator comprising an electromagnet;

a rotor rotatably sleeved on the mandrel and adapted to rotate around the stator;

the shell is rotatably sleeved on the mandrel and is suitable for rotating around the rotor and the mandrel, the shell is provided with a containing space, a first perforation, an opening and a side cover, the side cover is used for closing the opening and is provided with a second perforation, the containing space contains the stator and the rotor, the opening faces the second end, and the mandrel is respectively penetrated through the shell and the side cover through the first perforation and the second perforation;

the sleeve is sleeved at the second end of the mandrel and connected to the side cover, and is provided with a setting part which is positioned on the surface of one side of the sleeve away from the mandrel; and

the torque sensor is connected with the sleeve and provided with a sensing unit, and the sensing unit is arranged on the setting part.

2. The hub motor according to claim 1, wherein the sensing unit is spaced from the axis of the spindle by a distance of between 8.15mm and 12.6 mm.

3. The hub motor according to claim 1, further comprising an outer tube sleeved on the sleeve and covering the mounting portion and the torque sensor.

4. A hub motor according to claim 3, wherein the sleeve and the outer barrel together form an internal ratchet mechanism.

5. The hub motor of claim 4, wherein the outer tube is adapted to engage a gear set of the bicycle.

6. The hub motor according to claim 1, wherein the sensing unit is a strain gauge, the sensing direction of the strain gauge being arranged along the circumferential direction of the sleeve.

7. The hub motor according to claim 1, further comprising a power supply mechanism electrically connected to the torque sensor and including a first coil electrically connected to a power source and fixed to the spindle and a second coil fixed to the sleeve and parallel to the first coil and adapted to rotate relative to the first coil, the torque sensor being electrically connected to the second coil and electrically connected to the power source through the first coil and the second coil.