Mid-motor structure for two-wheeled vehicle and two-wheeled vehicle

Abstract

The utility model provides a kind of for two-wheeled vehicle's middle motor structure and two-wheeled vehicle, including stator core fixed installation on the inner wall of shell one side, the stator tooth of stator core is arranged around axis direction, winding is wound on stator core;The one end of motor shaft is rotatably installed on the inner wall of shell fixed installation stator core by bearing, the other end of motor shaft extends outward from the other side of shell, and the middle section of motor shaft is rotatably cooperated with the side wall of the other side of shell by bearing, rotor support is coaxially fixed installation on the shaft section of motor shaft that extends into shell, magnetic steel is fixed installation on the side wall opposite to rotor and stator core, the axis of motor shaft and the axis of stator core are collinear. By winding winding on the stator tooth of stator core arranged around axis direction, axial flux path is formed, cooperate disc type rotor, torque density is greater than the same volume radial flux motor, significantly improve the power density and torque density of motor, facilitate the miniaturization and lightweight design of middle motor.

Description

Technical Field

[0001] This utility model relates to the field of motor structure technology, specifically to a mid-mounted motor structure for a two-wheeled vehicle and the two-wheeled vehicle itself. Background Technology

[0002] Currently, mid-drive motors are mostly used in electric power assist systems for two-wheeled vehicles. As market demands increase, mid-drive motors in electric power assist systems for two-wheeled vehicles are developing towards miniaturization and lightweighting.

[0003] Chinese patent application CN120462569A discloses a mid-drive motor system and an electric-assisted bicycle, comprising: a torque sensor assembly, an output shaft assembly, a magnetic bracing assembly, a motor, and a controller; the motor gear shaft of the motor is connected to the output shaft assembly in pairs via double gears, and deceleration is performed on the output shaft assembly side; the output shaft assembly includes: a large gear, a one-way needle roller bearing, an output shaft, a third bearing, a ratchet, a pawl, a ratchet ring, and a tensioner; the torque sensor assembly is used to detect the torque of the mid-drive shaft, the magnetic bracing assembly is used to detect the rotational speed of the motor gear shaft, and the controller controls the output torque and rotational speed of the motor based on the detected torque and rotational speed.

[0004] Existing mid-drive motors employ a radial flux structure, where the flux path is distributed radially. This type of motor has the following limitations: 1. Torque density and power density are limited by rotor diameter, requiring increased volume to improve output, which makes it difficult to meet the requirements of lightweight design; 2. The cylindrical structure results in a space utilization rate of less than 60%, with the winding ends occupying ineffective space. Utility Model Content

[0005] In view of the deficiencies in the prior art, the purpose of this utility model is to provide a mid-mounted motor structure for a two-wheeled vehicle and a two-wheeled vehicle.

[0006] According to the present invention, a mid-mounted motor structure for a two-wheeled vehicle includes a housing, a stator core, windings, magnets, a rotor support, and a motor shaft. The stator core is fixedly installed on the inner wall of one side of the housing, the stator teeth of the stator core are arranged axially, and the windings are wound on the stator core. One end of the motor shaft is rotatably mounted on the inner wall of the housing where the stator core is fixedly mounted via a bearing. The other end of the motor shaft extends outward from the other side of the housing, and the middle section of the motor shaft is rotatably engaged with the side wall of the other side of the housing via a bearing. The rotor support is coaxially fixedly mounted on the shaft section of the motor shaft that extends into the housing. The magnet is fixedly mounted on the side wall opposite to the rotor and the stator core. The axis of the motor shaft is collinear with the axis of the stator core.

[0007] Preferably, the housing includes a left housing and a housing partition, wherein a cavity is formed inside the left housing to accommodate the stator core, windings, magnets and rotor support, and the housing partition is fixedly installed at the cavity opening of the left housing.

[0008] Preferably, a mounting groove is formed on the inner wall of the left housing opposite to the housing partition, and the stator core is fixedly mounted on the inner wall of the left housing by interference fit with the mounting groove through the inner diameter and / or outer diameter.

[0009] Preferably, multiple magnets are fixedly installed on the side wall of the rotor support opposite to the stator core by adhesive, and the multiple stator cores are arranged circumferentially along the rotor support.

[0010] Preferably, the magnet is fan-shaped, and the outer arc of the magnet coincides with the outer arc of the rotor support.

[0011] Preferably, the rotor support comprises an integral structure or a split structure.

[0012] Preferably, the integral structure of the rotor support is made entirely of magnetically conductive material.

[0013] Preferably, the split structure of the rotor support includes a rotor yoke and a rotor fixing bracket, wherein the rotor yoke is coaxially fixedly installed on the outer circle of the rotor fixing bracket; The rotor yoke and the stator core have opposite end faces and the same area. The magnets are fixedly installed on the side walls of the rotor yoke and the stator core.

[0014] Preferably, the shaft segment extending out of the housing from the motor shaft includes a gear shaft structure.

[0015] The present invention provides a two-wheeled vehicle with a mid-mounted motor structure.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. This utility model forms an axial magnetic flux path by winding the windings on the stator teeth arranged axially around the stator core. Combined with a disc rotor, the torque density is greater than that of a radial flux motor of the same volume, which significantly improves the power density and torque density of the motor and facilitates the miniaturization and lightweight design of the mid-drive motor.

[0017] 2. Through the axial magnetic flux layout, the overall structure of the motor is flat, and the internal space utilization rate of the motor exceeds 75%, which significantly shortens the axial space of the motor. Attached Figure Description

[0018] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a cross-sectional view that mainly illustrates the overall structure of the motor in this utility model; Figure 2 This is an exploded view showing the overall structure of the motor, which is the main feature of this utility model. Figure 3 This is a cross-sectional view that mainly illustrates the overall structure of the mid-drive motor in this utility model.

[0019] Reference numerals: 1. Right housing; 2. Left housing; 3. Stator core; 4. Winding; 5. Magnet; 6. Rotor support; 61. Rotor yoke; 62. Rotor fixing support; 7. Housing partition; 8. Central shaft body; 9. Motor shaft; 10. Transmission shaft; 11. Mounting point; 12. First gear; 13. Gear output shaft; 14. Clutch; 15. Sensor assembly; 16. Positioning bushing. Detailed Implementation

[0020] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0021] Example 1 like Figures 1 to 3 As shown, the present invention provides a mid-drive motor structure for a two-wheeled vehicle, comprising a housing, a stator core 3, windings 4, magnets 5, a rotor support 6, and a motor shaft 9. The stator core 3 is fixedly mounted on the inner wall of one side of the housing, and the stator teeth of the stator core 3 are arranged axially. The windings 4 are wound around the stator core 3. One end of the motor shaft 9 is rotatably mounted on the inner wall of the housing where the stator core 3 is fixedly mounted via a bearing. The other end of the motor shaft 9 extends outward from the other side of the housing, and the middle section of the motor shaft 9 is rotatably engaged with the side wall of the other side of the housing via a bearing. The rotor support 6 is coaxially fixedly mounted on the shaft section of the motor shaft 9 that extends into the housing. The magnets 5 are fixedly mounted on the side walls of the rotor opposite to the stator core 3. The axis of the motor shaft 9 is collinear with the axis of the stator core 3.

[0022] The technical solution of this application forms an axial magnetic flux path by winding the winding 4 around the stator teeth arranged axially around the stator core 3. Combined with a disc-type rotor, the torque density is greater than that of a radial flux motor of the same volume, significantly improving the power density and torque density of the motor, and facilitating the miniaturization and lightweight design of mid-drive motors. Furthermore, the axial magnetic flux layout of this application results in a flat overall structure for the motor, with an internal space utilization rate exceeding 75%, significantly shortening the axial space of the motor.

[0023] Specifically, the housing includes a left housing 2 and a housing partition 7. The left housing 2 has a cavity forming to accommodate the stator core 3, windings 4, magnets 5, and rotor support 6. The housing partition 7 is fixedly installed at the opening of the cavity in the left housing 2. In one feasible embodiment, the connection structure between the housing partition 7 and the left housing 2 can be as follows: the left housing 2 has a mounting position at the opening of the cavity, and the housing partition 7 is fixedly installed at the mounting position using fasteners such as screws and bolts. The housing partition 7 closes the opening of the cavity in the left housing 2 to form the motor structure.

[0024] More specifically, a mounting groove is formed on the inner wall of the left housing 2 opposite to the housing partition 7. The stator core 3 is fixedly mounted on the inner wall of the left housing 2 by interference fit with the mounting groove through its inner diameter and / or outer diameter. The stator core 3 is embedded and fixed in the inner wall of the left housing 2 by its dimensional design, without the need for other fixing structures and fasteners, which improves the utilization rate of the internal space of the motor and meets the development requirements of motor miniaturization and lightweighting. More specifically, the stator core 3 can be made of integral SMC composite material or amorphous alloy powder sintering. The stator teeth of the stator core 3 are located on the side of the stator core 3 close to the rotor support 6, and the end of the stator core 3 away from the rotor support 6 is the mating part between the stator core 3 and the mounting groove. The stator assembly consists of the stator core 3 and the winding 4. After the stator assembly is installed in the left housing 2, it adopts an integral potting process to improve the heat dissipation of the motor.

[0025] Furthermore, multiple magnets 5 are fixedly installed on the sidewalls of the rotor support 6 opposite to the stator core 3 using adhesive, and the multiple stator cores 3 are arranged circumferentially along the rotor support 6. The magnets 5 are fan-shaped, and the outer arc of the magnets 5 coincides with the outer arc of the rotor support 6, which significantly improves the magnetic field strength of the motor rotor.

[0026] The rotor support 6 can be either an integral structure or a split structure. In one feasible embodiment, the integral structure of the rotor support 6 is made entirely of magnetically conductive material. In another feasible embodiment, the split structure of the rotor support 6 includes a rotor yoke 61 and a rotor fixing bracket 62, with the rotor yoke 61 coaxially fixedly mounted on the outer circumference of the rotor fixing bracket 62. The rotor yoke 61 and the stator core 3 are positioned opposite each other and have the same area, and magnets 5 are fixedly mounted on the sidewalls of the rotor yoke 61 opposite to the stator core 3.

[0027] The section of the motor shaft 9 extending out of the housing includes a gear shaft structure, which is formed by hobbing the shaft end and is used to output power.

[0028] The present invention provides a two-wheeled vehicle with a mid-mounted motor structure.

[0029] Example 2 like Figures 1 to 3 As shown in Embodiment 1, a modular mid-mounted motor structure for a two-wheeled vehicle provided by this utility model includes a left housing 2, a right housing 1, a motor module, a transmission module, and a central shaft module. The motor module is integrated and installed on the left housing 2, the central shaft module is integrated and installed on the right housing 1, and the transmission module is integrated and installed in the space formed by the left housing 2 and the right housing 1.

[0030] The motor module includes a stator core 3, windings 4, magnets 5, a rotor support 6, a motor shaft 9, and a housing partition 7. The housing partition 7 is fixedly connected to the left housing 2 and forms a cavity to accommodate the stator core 3, windings 4, magnets 5, and rotor support 6. The stator core 3 is fixedly installed on the inner wall of the left housing 2. The stator teeth of the stator core 3 are arranged axially. The windings 4 are wound on the stator core 3. One end of the motor shaft 9 is rotatably installed on the left housing 2. The rotor support 6 is fixedly installed on the motor shaft 9. The magnets 5 are installed on the side wall of the rotor support 6 opposite to the stator core 3. The other end of the motor shaft 9 extends out of the housing partition 7.

[0031] The central shaft module includes a central shaft body 8, which is rotatably mounted on the right housing 1. The left housing 2 has mounting points 11 for rotatably mounting the central shaft body 8. The transmission module includes a transmission shaft 10 and a transmission gear set. The transmission shaft 10 and the transmission gear set cooperate to drive the output end of the motor shaft 9 to the central shaft body 8. Mounting points 11 for rotatably mounting the transmission shaft 10 are provided on both the right housing 1 and the housing partition 7.

[0032] The technical solution of this application integrates the motor module on the left housing 2 and the central shaft module on the right housing 1 through modular design. This allows for separate processing followed by unified assembly. The mounting points 11 on the left housing 2 for rotating the central shaft body 8, the mounting points 11 on the housing partition 7 for rotating the drive shaft 10, and the mounting points 11 on the right housing 1 for rotating the drive shaft 10 are used as positioning points for assembly, which improves the accuracy of assembly and makes assembly, maintenance, and replacement convenient.

[0033] Specifically, the motor module of this application forms an axial magnetic flux path by winding the winding 4 around the stator teeth arranged axially around the stator core 3. Combined with a disc-type rotor, the torque density is greater than that of a radial flux motor of the same volume, significantly improving the power density and torque density of the motor, facilitating the miniaturization and lightweight design of mid-drive motors. Furthermore, the axial magnetic flux layout of this application results in a flat overall structure for the motor, with an internal space utilization rate exceeding 75%, significantly shortening the axial space of the motor.

[0034] One end of the motor shaft 9 is rotatably mounted on the inner wall of the left housing 2 via a bearing, and the middle section of the motor shaft 9 is rotatably engaged with the housing partition 7 via a bearing. The shaft section of the motor shaft 9 extending out of the housing includes a gear shaft structure, which is formed by hobbing the shaft end and is used for power output.

[0035] The left housing 2 forms a cavity to accommodate the stator core 3, winding 4, magnet 5, and rotor support 6. A housing partition 7 is fixedly installed at the opening of this cavity in the left housing 2. In one feasible embodiment, the connection structure between the housing partition 7 and the left housing 2 can be as follows: the left housing 2 has a mounting position at the opening of the cavity, and the housing partition 7 is fixedly installed at this mounting position using screws, bolts, or other fasteners. The housing partition 7 closes the opening of the cavity in the left housing 2 to form a motor structure.

[0036] More specifically, a mounting groove is formed on the inner wall of the left housing 2 opposite to the housing partition 7. The stator core 3 is fixedly mounted on the inner wall of the left housing 2 by interference fit with the mounting groove through its inner diameter and / or outer diameter. The stator core 3 is embedded and fixed in the inner wall of the left housing 2 by its dimensional design, without the need for other fixing structures and fasteners, which improves the utilization rate of the internal space of the motor and meets the development requirements of motor miniaturization and lightweighting. More specifically, the stator core 3 is made of integral SMC composite material or amorphous alloy powder sintering. The stator teeth of the stator core 3 are located on the side of the stator core 3 close to the rotor support 6, and the end of the stator core 3 away from the rotor support 6 is the mating part between the stator core 3 and the mounting groove. The stator assembly consists of the stator core 3 and the winding 4. After the stator assembly is installed in the left housing 2, it adopts an integral potting process to improve the heat dissipation of the motor.

[0037] Furthermore, multiple magnets 5 are fixedly installed on the sidewalls of the rotor support 6 opposite to the stator core 3 using adhesive, and the multiple stator cores 3 are arranged circumferentially along the rotor support 6. The magnets 5 are fan-shaped, and the outer arc of the fan-shaped magnets 5 coincides with the outer arc of the rotor support 6, which significantly improves the magnetic field strength of the motor rotor.

[0038] The rotor support 6 can be either an integral structure or a split structure. In one feasible embodiment, the integral structure of the rotor support 6 is made entirely of magnetically conductive material. In another feasible embodiment, the split structure of the rotor support 6 includes a rotor yoke 61 and a rotor fixing bracket 62, with the rotor yoke 61 coaxially fixedly mounted on the outer circumference of the rotor fixing bracket 62. The rotor yoke 61 and the stator core 3 are positioned opposite each other and have the same area, and magnets 5 are fixedly mounted on the sidewalls of the rotor yoke 61 opposite to the stator core 3.

[0039] In one feasible implementation, the transmission gear set includes a first gear 12 and a gear output shaft 13. The first gear 12 is coaxially fixedly mounted on the transmission shaft 10, and meshes with one end of the motor shaft 9 extending out of the housing partition 7. The gear output shaft 13 is rotatably mounted on the right housing 1 via bearings. The gear output shaft 13 has a stepped surface inside for mounting the bearings. The central shaft body 8 is coaxially assembled with the gear output shaft 13 via bearings, and the central shaft body 8 is fixedly or rotatably connected to the gear output shaft 13. The transmission shaft 10 also includes a gear shaft section, and the gear output shaft 13 meshes with the gear shaft section of the transmission shaft 10.

[0040] In one feasible embodiment, the gear output shaft 13 is rotatably mounted on the right housing 1 via a bearing, and a clutch 14 is provided between the gear output shaft 13 and the central shaft body 8. The clutch 14 enables a fixed connection or a rotatable connection between the central shaft body 8 and the gear output shaft 13.

[0041] The central axis module also includes a sensor assembly 15 and a positioning bushing 16. The sensor assembly 15 is mounted on the central axis body 8, and the positioning bushing 16 is coaxially sleeved on the outside of the sensor assembly 15, and the positioning bushing 16 is positioned and assembled with the shaft segment of the central axis body 8. It should be noted that the positioning bushing 16 can cooperate with the stepped structure provided on the central axis body 8 to realize the positioning and assembly of the central axis module on the right housing 1.

[0042] The mounting points 11 on the right housing 1 and the housing partition 7 allow the drive shaft 10 to be positioned and assembled via bearings. It should be noted that the assembly of the shaft and bearings in this application can both be achieved by press-fitting.

[0043] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0044] The specific embodiments of this utility model have been described above. It should be understood that this utility model is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the substantive content of this utility model. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A mid-mounted motor structure for a two-wheeled vehicle, characterized in that, The motor includes a housing, a stator core (3), a winding (4), a magnet (5), a rotor support (6), and a motor shaft (9). The stator core (3) is fixedly installed on the inner wall of one side of the housing. The stator teeth of the stator core (3) are arranged axially. The winding (4) is wound on the stator core (3). One end of the motor shaft (9) is rotatably mounted on the inner wall of the housing where the stator core (3) is fixedly mounted. The other end of the motor shaft (9) extends outward from the other side of the housing. The middle section of the motor shaft (9) is rotatably engaged with the side wall of the other side of the housing through the bearing. The rotor bracket (6) is coaxially fixedly mounted on the shaft section of the motor shaft (9) that extends into the housing. The magnet (5) is fixedly mounted on the side wall opposite to the rotor and the stator core (3). The axis of the motor shaft (9) is collinear with the axis of the stator core (3).

2. The mid-mounted motor structure for a two-wheeled vehicle as described in claim 1, characterized in that, The housing includes a left housing (2) and a housing partition (7). The left housing (2) forms a cavity that accommodates the stator core (3), winding (4), magnet (5) and rotor support (6). The housing partition (7) is fixedly installed at the cavity opening of the left housing (2).

3. The mid-mounted motor structure for a two-wheeled vehicle as described in claim 2, characterized in that, The left housing (2) has an installation groove on its inner wall opposite to the housing partition (7). The stator core (3) is fixedly installed on the inner wall of the left housing (2) by interference fit with the installation groove through its inner diameter and / or outer diameter.

4. The mid-mounted motor structure for a two-wheeled vehicle as described in claim 1, characterized in that, Multiple magnets (5) are fixedly installed on the side wall opposite to the stator core (3) of the rotor bracket (6) by glue, and the multiple stator cores (3) are arranged circumferentially along the rotor bracket (6).

5. The mid-mounted motor structure for a two-wheeled vehicle as described in claim 1, characterized in that, The magnet (5) is fan-shaped, and the outer arc of the magnet (5) coincides with the outer arc of the rotor support (6).

6. The mid-mounted motor structure for a two-wheeled vehicle as described in claim 1, characterized in that, The rotor support (6) includes an integral structure or a split structure.

7. The mid-mounted motor structure for a two-wheeled vehicle as described in claim 6, characterized in that, The rotor support (6) has an integral structure made of magnetically conductive material.

8. The mid-mounted motor structure for a two-wheeled vehicle as described in claim 6, characterized in that, The split structure of the rotor support (6) includes a rotor yoke (61) and a rotor fixing bracket (62), and the rotor yoke (61) is coaxially fixedly installed on the outer circle of the rotor fixing bracket (62). The rotor yoke (61) and the stator core (3) are arranged opposite to each other and have the same area. The magnet (5) is fixedly installed on the side wall opposite to the rotor yoke (61) and the stator core (3).

9. The mid-mounted motor structure for a two-wheeled vehicle as described in claim 1, characterized in that, The section of the motor shaft (9) extending out of the housing includes a gear shaft structure.

10. A two-wheeled vehicle, characterized in that, The mid-mounted motor structure for a two-wheeled vehicle as described in any one of claims 1 to 9 is adopted.

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