Bicycle hub motor with housing positioning structure

Abstract

A bicycle hub motor with a housing positioning structure includes a spindle assembly, a hub, a motor, a rotor seat, and a ratchet seat. The hub has a body, an annular connector, and a side cover. The body has an accommodating space and an opening, the accommodating space for accommodating the motor and the rotor seat. The annular connector is attached to the body and adjacent to the opening. The side cover is attached to the body to cover the opening and abuts against the annular connector. The side cover has a first protruding ring, the inner surface of the side cover forms abutting surface, and the inner circumferential surface of the first protruding ring forms a limiting surface. The ratchet seat has a disc portion, which is attached to the abutting surface and contacts the limiting surface. The annular connector improves the concentricity between the body and the side cover, and the first protruding ring achieves the effect of positioning the ratchet seat, providing a spindle assembly alignment mechanism and avoiding problems such as misalignment of the spindle assembly leading to assembly difficulties.

Description

Technical Field

[0001] This invention relates to a bicycle hub motor; in particular, it refers to a bicycle hub motor with a housing positioning structure. Prior Technology

[0002] A hub motor is known to rotate its housing through an internal drive mechanism. When used in bicycles, it is typically mounted on the axle of the front or rear wheel, with the hub motor's housing structure fixed to the wheel. Thus, when the hub motor is activated, the internal drive mechanism rotates the housing, which in turn drives the wheel connected to the hub motor's housing to rotate, achieving an assisted riding effect.

[0003] However, existing hub motors generally lack a good concentric positioning design between the drive mechanism and the housing, and the housing itself also lacks a positioning structure to improve concentricity. This leads to problems such as spindle misalignment or structural eccentricity during assembly. Although some products improve the above situation by increasing the tolerance accuracy of components, they still lack an effective geometric positioning structure, which can easily cause assembly problems and positioning misalignment. These problems not only reduce assembly efficiency but may also shorten the life of the hub motor. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a bicycle hub motor with a housing positioning structure, which can improve the concentricity between the drive mechanism and the housing and improve the problems of spindle misalignment and eccentricity.

[0005] To achieve the above objectives, the present invention provides a bicycle hub motor with a housing positioning structure, comprising a spindle assembly, a hub, a motor, a rotor seat, and a ratchet seat. The spindle assembly includes a spindle and a stator seat, with a rotation axis defined by the centerline of the spindle. The stator seat is connected to the outer peripheral surface of the spindle. The hub includes a body, an annular connector, and a side cover. The body has an accommodating space with an opening. The outer peripheral surface of the body forms a plurality of spoke seats. The center of the body has a first through hole, and the stator seat is accommodated in the accommodating space. The annular connector is coupled to the inner peripheral surface of the body and adjacent to the opening. The periphery of the side cover is coupled to the body to cover the opening and abut against the annular connector. The center of the side cover has an opening, and a first protruding ring is connected to the inner surface of the side cover around the opening. The inner surface of the side cover, between the opening and the first convex ring, forms a contact surface. The inner circumferential surface of the first convex ring forms a limiting surface, and the contact surface and the limiting surface are not parallel. The motor is disposed in the accommodating space and includes a stator and a rotor. The stator is fixed around the stator seat, and the rotor surrounds the outer circumferential surface of the stator and can rotate relative to the stator. The rotor seat is coupled to the rotor and is sleeved on the spindle in a manner that allows it to rotate along the axis of rotation. The ratchet seat includes a hub connecting part and a sprocket connecting part. The hub connecting part includes a disc part, and the disc part is coupled to the contact surface. The outer circumferential surface of the disc part contacts the limiting surface. The sprocket connecting part is rotatably sleeved around the spindle. A one-way drive structure is provided between the sprocket connecting part and the hub connecting part. The radial outer circumferential surface of the sprocket connecting part is provided with multiple grooves.

[0006] The effect of this invention is that the side cover, through the abutment surface and the limiting surface formed by the first convex ring, achieves the effect of well positioning and engaging the disc portion of the ratchet seat at the center of the side cover, ensuring that the ratchet seat also rotates around the rotation axis as the center of rotation. During assembly, it can provide a good alignment mechanism for the spindle assembly, avoiding problems such as misalignment of the spindle assembly and assembly difficulties. Simple Explanation of the Diagram

[0007] Figure 1 is a perspective view of a bicycle hub motor with a housing positioning structure according to a preferred embodiment of the present invention. Figure 2 is a partial exploded view of the bicycle hub motor with a housing positioning structure according to the above preferred embodiment. Figure 3 is a partial exploded view of Figure 2 from another perspective. Figure 4 is an exploded view of the mandrel assembly. Figure 5 is a front view of the bicycle hub motor with a housing positioning structure according to the above preferred embodiment. Figure 6 is a cross-sectional view along direction 6-6 of Figure 5. Figure 6A is a cross-sectional view similar to Figure 6, revealing the connection method of the deceleration mechanism. Figure 7 is a cross-sectional view along direction 7-7 of Figure 5. Implementation

[0008] To more clearly illustrate the present invention, preferred embodiments are described in detail below with reference to the accompanying drawings. Referring to Figures 1 to 3 and Figure 6, a preferred embodiment of the present invention is a bicycle hub motor 100 with a housing positioning structure, comprising a spindle assembly 10, a hub 20, a motor 30, a rotor seat 40, a reduction mechanism 50, and a ratchet seat 60. The following description of the bicycle hub motor 100 will focus on the front-back and up-down directions of each part of the bicycle hub motor 100 in its operational state.

[0009] As shown in Figures 4 to 6, the spindle assembly 10 includes a spindle 12 and a stator seat 14. The spindle 12 has a first shaft portion 121 and a second shaft portion 122. A rotation axis L is defined by the center line of the first shaft portion 121 and the second shaft portion 122, and the rotation axis L serves as the rotation center of the bicycle hub motor 100. The first shaft portion 121 has a hollow tube 1211, and a sleeve hole 1212 is formed at one end of the hollow tube 1211. The sleeve hole 1212 is a non-circular hole, and the inner circumferential surface of the non-circular hole... The second shaft 122 is roughly circular with parallel surfaces on opposite sides. The outer peripheral surface of the end of the second shaft 122 facing the first shaft 121 is a non-circular outer peripheral surface 1221 that mates with a non-circular hole. The end of the second shaft 122 with the non-circular outer peripheral surface 1221 is embedded in the sleeve hole 1212. In this way, the second shaft 122 is connected to the first shaft 121 and will not rotate relative to the first shaft 121. The stator seat 14 is a circular disc and the inner peripheral surface of the stator seat 14 is connected to the outer peripheral surface of the hollow tube 1211.

[0010] As shown in Figures 2, 5, and 6, the hub 20 includes a body 22, an annular connector 24, and a side cover 25. The body 22 is a transversely arranged groove, with an opening 221 formed on the right side. The body 22 has a plurality of spoke seats 222, a first through hole 223, and an accommodating space S. The spoke seats 222 are disposed on the outer peripheral surface of the body 22. The two ends of the bicycle spokes are respectively connected to the spoke seats 222 and the bicycle rim. When the body 22 rotates, the bicycle rim can be rotated through the bicycle spokes. The first through hole 223 is located at the center of the left side of the body 22. The first perforation 223 has a main bearing seat 2231, and a first bearing 26 is embedded in the main bearing seat 2231. The hollow tube 1211 of the first shaft portion 121 is pivotally inserted through the first bearing 26. The main body 22 is rotatably fitted onto the first shaft portion 121 by means of the first bearing 26. In this way, when the first shaft portion 121 is fixed, the main body 22 can rotate relative to the first shaft portion 121 about the rotation axis L. The accommodating space S is formed inside the main body 22, and the opening 221 is formed on the right side of the accommodating space S. The accommodating space S is used to accommodate the stator seat 14, the motor 30, the rotor seat 40 and the reduction mechanism 50.

[0011] As shown in Figures 2 to 3 and Figures 5 to 6, the annular connector 24 is a circular ring and is screwed onto the inner circumferential surface of the body 22. The annular connector 24 is adjacent to the opening 221 and has an annular positioning groove 241 on its outer surface facing the opening 221. The side cover 25 is a circular cover and is screwed onto the body 22, so that the side cover 25 covers the opening 221 and abuts against the annular connector 24. The side cover 25 has an opening 251, a first protruding ring 252, and a second protruding ring 253. The opening 251 is located at the center of the side cover 25. A protruding ring 252 is disposed on the inner side of the side cover 25 around the opening 251. The portion of the inner side of the side cover 25 between the first protruding ring 252 and the opening 251 forms an abutment surface 254. The inner circumferential surface of the first protruding ring 252 forms a limiting surface 255. The abutment surface 254 and the limiting surface 255 are not parallel. In this preferred embodiment, the limiting surface 255 is perpendicular to the abutment surface 254. A second protruding ring 253 is disposed on the periphery of the inner side of the side cover 25. The second protruding ring 253 is engaged in the positioning groove 241, thereby increasing the concentricity of the side cover 25 and the body 22 during assembly.

[0012] As shown in Figures 5 and 6, the motor 30 includes a stator 32 and a rotor 34. The stator 32 is fixed to the outer circumferential surface of the stator seat 14. A third convex ring 341 is attached to the outer surface of the rotor 34. The rotor 34 is spaced apart from the stator 32 and surrounds the stator 32. The rotor seat 40 has a rotor seat positioning groove 41 and a rotor bearing seat 42. The third convex ring 341 is engaged in the rotor seat positioning groove 41. When the rotor 34 rotates, it can drive the rotor seat 40 to rotate. The rotor bearing seat 42 is located at the center of the rotor seat 40. Two third bearings 43 are embedded in the rotor bearing seat 42. A part of the second shaft portion 122 pivotally passes through the two third bearings 43. The rotor 34 and the rotor seat 40 are rotatably fitted onto the second shaft portion 122 by means of the two third bearings 43.

[0013] As shown in Figures 5 and 6, a power cable 70 is externally connected to the bicycle hub motor 100. The power cable 70 is electrically connected to the stator 32, so current can be passed into the stator 32 to generate an electromagnetic field, which in turn generates a driving force to rotate the rotor 34, thereby causing the rotor base 40 to rotate relative to the stator 32 around the rotation axis L. The rotational speed of the rotor 34 relative to the stator 32 can be controlled by changing the input voltage or frequency.

[0014] As shown in Figure 6A, the reduction mechanism 50 includes an input end 51, an output end 52, a planetary gear carrier 53, a plurality of first planetary gears 54, and a plurality of second planetary gears 55. The input end 51 is a ring-shaped sun gear concentrically coupled to the central portion of the rotor seat 40. A second shaft portion 122 passes through the middle of the input end 51, allowing the input end 51 to be rotatably disposed around the second shaft portion 122. The output end 52 is a circular gear ring coupled to an annular connector 24. The planetary gear carrier 53 is an annular body with a plurality of annularly arranged shaft holes 531. The planetary gear carrier 53 surrounds the second shaft portion 122 and can rotate relative to the second shaft portion 122 about the rotation axis L. A pin 56 is pivotally inserted through each of the shaft holes 531. The first planetary gears 54 are arranged in a ring around the input end 51 and mesh with the input end 51. The center of each of the first planetary gears 54 is rotatably connected to one end of each pin 56. The second planetary gears 55 are arranged in a ring and mesh with the output end 52. The center of each of the second planetary gears 55 is rotatably connected to the other end of each pin 56.

[0015] During operation, the rotor base 40 drives the input end 51 to rotate, the input end 51 drives the first planetary gears 54 to rotate, the first planetary gears 54 in turn drive the planetary gear carrier 53 and the second planetary gears 55 to rotate, the second planetary gears 55 mesh with the output end 52, and finally make the annular connector 24 rotate at a lower speed relative to the input end 51, so as to achieve the effect of deceleration.

[0016] As shown in Figures 2, 3 and 7, the ratchet seat 60 includes a hub connecting part 62 and a sprocket connecting part 64. The hub connecting part 62 includes a cylindrical body 621 and a disc part 622. The cylindrical body 621 is a cylindrical tube. The cylindrical body 621 is slightly larger than the second shaft part 122, and the cylindrical body 621 is rotatably fitted onto the second shaft part 122. The outer circumferential surface of the cylinder body 621 is provided with three ratchet grooves 623, and a ratchet 624 is provided in each ratchet groove 623. The inner circumferential surface of the disc part 622 is connected to the inner end of the cylinder body 621. The disc part 622 has a plurality of first fastener holes 625 and a second through hole 626. During installation, the cylinder body 621 passes through the opening 251, so that the disc part 622 abuts against the abutment surface 254. The abutment surface 254 forms a plurality of second fastener holes 256 corresponding to the positions of the first fastener holes 625. A fastener 27 is inserted into each second fastener hole 256. Each fastener 27 passes through each first fastener hole 625, so that the disc part 622 is engaged with the abutment surface 254, and the outer circumferential surface of the disc part 622 contacts the limiting surface 255, thereby increasing the concentricity of the hub connection part 62 and the side cover 25.

[0017] As shown in Figures 2, 3 and 6, the second perforation 626 is located at the center of the disc portion 622. The second perforation 626 has a disc bearing seat 6261, and a second bearing 66 is embedded in the disc bearing seat 6261. The other end of the second shaft portion 122 is pivotally connected to the second bearing 66 and the cylinder body 621 in sequence. The hub connecting portion 62 is rotatably fitted onto the second shaft portion 122 by means of the second bearing 66. The hub connecting portion 62 can rotate relative to the second shaft portion 122 around the rotation axis L.

[0018] As shown in Figures 2, 3, and 7, the sprocket connection part 64 is a cylindrical body and rotatably fits around the hub connection part 62. The sprocket connection part 64 has multiple ratchet teeth 641 and multiple slots 642. Each ratchet tooth 641 is arranged in a circular manner on the inner circumferential surface of the sprocket connection part 64. Each pawl 624 engages with each ratchet tooth 641 in a unidirectional engagement manner. A unidirectional drive structure X is formed between the hub connection part 62 and the sprocket connection part 64, meaning that the sprocket connection part 64 can only drive the hub connection part 62 forward. When the sprocket connection 64 rotates backward, the sprocket connection 64 cannot drive the hub connection 62 to rotate backward together. Each groove 642 is provided on the radial outer circumferential surface of the sprocket connection 64. The sprocket connection 64 is connected to a freewheel (not shown in the figure) through each groove 642. The bicycle chain is wrapped around the freewheel. When the user steps forward on the bicycle pedal, the bicycle chain drives the freewheel to rotate, and then drives the hub 20 of the bicycle hub motor 100 to rotate through the one-way drive structure X.

[0019] In summary, the advantages of this invention are that the side cover 25 is engaged with the positioning groove 241 of the annular connector 24 by the second protruding ring 253, and the side cover 25 is screwed onto the body 22, which can increase the concentricity between the body 22 and the side cover 25, ensuring that the first through hole 223 of the body 22 and the opening 251 of the side cover 25 are both centered on the rotation axis L; and the side cover 25 achieves good positioning of the ratchet seat 60 disc 622 at the center of the side cover 25 by the abutment surface 254 and the limiting surface 255 formed by the first protruding ring 252, ensuring that the ratchet seat 60 is also centered on the rotation axis L. During assembly, this provides a good alignment mechanism for the spindle assembly 10, avoiding problems such as misalignment of the spindle assembly 10.

[0020] The above description is only a preferred embodiment of the present invention. Any equivalent changes made by applying the present invention specification and the claims should be included within the patent scope of the present invention.

[0021] 100: Bicycle hub motor 10: Spindle assembly 12: Mandrel 121: First shaft section 1211: Hollow tube 1212: Sleeve 122: Second shaft section 1221: Non-circular outer circumference 14: Stator 20: Wheel hub 22:Ontology 221: Opening 222: Spoke seat 223: First perforation 2231: Body bearing housing 24: Ring connector 241: Positioning groove 25: Side Cover 251: Opening 252: First convex ring 253: Second convex ring 254: Supporting surface 255: Restricted Surface 256: Second fastener hole 26: First Bearing 27: Fasteners 30: Motor 32: Stator 34: Rotor 341: Third convex ring 40: Rotor base 41: Rotor seat positioning groove 42: Rotor bearing housing 43: Third bearing 50: Reduction Mechanism 51: Input terminal 52: Output terminal 53: Planetary Gear Carrier 531: Shaft Hole 54: First Planetary Gear 55: Second Planetary Gear 56: Pin 60: Ratchet 62: Wheel hub connection 621: Tube Body 622: Plate 623: Ratchet Groove 624: Spiked Claw 625: First fastener hole 626: Second perforation 6261: Disc bearing housing 64: Sprocket connection part 641: Ratchet 642: Groove 66: Second bearing 70: Power cord L: Axis of rotation S: Storage space X: Unidirectional drive structure

Claims

1. A bicycle hub motor with a housing positioning structure, comprising: a spindle assembly including a spindle and a stator seat, wherein a rotation axis is defined by the center line of the spindle, and the stator seat is connected to the outer peripheral surface of the spindle; A wheel hub includes a body, an annular connector, and a side cover. The body has an accommodating space with an opening. The outer peripheral surface of the body forms a plurality of spoke seats. The center of the body has a first through hole, and the stator seat is accommodated in the accommodating space. The annular connector is attached to the inner peripheral surface of the body and adjacent to the opening. The outer side of the annular connector facing the opening has an annular positioning groove. The periphery of the side cover is attached to the body to cover the opening and abut against the annular connector. The center of the side cover has an opening. A first protruding ring is connected to the inner side of the side cover around the opening. The portion of the inner side of the side cover between the opening and the first protruding ring forms a bearing surface. The inner peripheral surface of the first protruding ring forms a limiting surface, and the bearing surface is not parallel to the limiting surface. A second protruding ring is connected to the periphery of the inner side of the side cover, and the second protruding ring engages in the positioning groove. A motor, disposed in the accommodating space, includes a stator and a rotor. The stator is fixed to the outer peripheral surface of the stator seat, and the rotor surrounds the stator and is rotatable relative to the stator. A rotor seat is coupled to the rotor and is fitted onto the spindle in a manner rotatable along the axis of rotation. A ratchet seat includes a hub connection portion and a sprocket connection portion. The hub connection portion includes a disc portion, which is coupled to the abutment surface, and the outer peripheral surface of the disc portion contacts the limiting surface. The sprocket connection portion is rotatably surrounded by the spindle, and a one-way drive structure is provided between the sprocket connection portion and the hub connection portion. The radial outer peripheral surface of the sprocket connection portion is provided with a plurality of slots.

2. A bicycle hub motor with a housing positioning structure as described in claim 1, wherein the disc portion has a plurality of first fastener holes, the abutment surface forms a plurality of second fastener holes corresponding to the positions of the first fastener holes, a fastener is inserted into each of the second fastener holes, and each fastener passes through each of the first fastener holes.

3. A bicycle hub motor with a housing positioning structure as described in claim 1, wherein the first through hole of the body has a body bearing seat, and a first bearing is embedded in the body bearing seat; wherein the center of the disc portion has a second through hole, the second through hole has a disc portion bearing seat, and a second bearing is embedded in the disc portion bearing seat; one end of the spindle passes through the first bearing, and the other end of the spindle passes through the second bearing.

4. The bicycle hub motor with a housing positioning structure as described in claim 3, wherein the spindle includes a first shaft portion and a second shaft portion, the first shaft portion having a hollow tube pivotally inserted through the first bearing, and a sleeve hole being formed at one end of the hollow tube facing the opening, the sleeve hole being a non-circular hole, one end of the second shaft portion being fitted into the sleeve hole, and the other end of the second shaft portion pivotally inserted through the second bearing.

5. A bicycle hub motor with a housing positioning structure as described in claim 4, wherein the inner circumferential surface of the stator housing is connected to the outer circumferential surface of the hollow tube.

6. The bicycle hub motor with a housing positioning structure as described in claim 1, wherein the sprocket connection portion is provided with a plurality of ratchet teeth, the hub connection portion is provided with a plurality of pawl grooves, each pawl groove is provided with a pawl, and each pawl is engaged with each ratchet tooth in a one-way engagement manner.

7. The bicycle hub motor with housing positioning structure as described in claim 1, further comprising a reduction mechanism disposed within the accommodating space and including an input end and an output end, the input end being a sun gear coupled to the center of the rotor seat, the input end being rotatably disposed around the spindle, and the output end being a gear ring coupled to the annular connector.

8. A bicycle hub motor with a housing positioning structure as described in claim 7, wherein the reduction mechanism further comprises a planetary gear carrier, a plurality of first planetary gears and a plurality of second planetary gears, the planetary gear carrier surrounding the spindle, the first planetary gears being rotatably coupled to one side of the planetary gear carrier and arranged in a ring around the input end, the first planetary gears meshing with the input end; the second planetary gears being rotatably coupled to the other side of the planetary gear carrier and arranged in a ring meshing with the output end.

9. A bicycle hub motor with a housing positioning structure as described in claim 8, wherein the planetary gear carrier has a plurality of shaft holes arranged in an annular pattern, through which a pin is pivotally inserted, the centers of the first planetary gears are rotatably coupled to one end of the pin, and the centers of the second planetary gears are rotatably coupled to the other end of the pin.

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