An electric vehicle in-wheel drive module system assembly

Abstract

The application relates to an in-wheel drive module system assembly of an electric vehicle, and relates to the field of electric vehicle drive technology, which comprises a disc hub type drive motor arranged in the inside of a rim, a built-in gear reduction mechanism of a disc hub type drive motor hub load end cover, an external brake caliper, a built-in motor stator, a motor rotor and a motor rotor shaft in a hub shell, a built-in motor controller in a hub load suspension end cover, and a gear reduction mechanism output main shaft main drive output main shaft; one end of the disc hub type drive motor rotor shaft is provided with a gear drive to drive the gear reduction mechanism to rotate, the gear reduction mechanism is built in a front cavity, the motor is built in a middle cavity, and the motor controller is built in a rear cavity. The application has the effects of improving the utilization rate of the in-vehicle space, improving the structural rigidity and strength, improving the reliability, and realizing the separate control of each wheel.

Description

Technical Field

[0001] This application relates to the field of electric vehicle drive technology, and in particular to an in-wheel drive module system assembly for an electric vehicle. Background Technology

[0002] The electric drive system is a key component of electric and hybrid vehicles, primarily responsible for converting electrical energy into mechanical energy to drive the vehicle's tires.

[0003] Existing electric vehicle wheel drive systems include a disc-wheel hub drive motor, a transmission mounted on the disc-wheel hub drive motor and connected to its output shaft, a brake disc mounted on the output end of the transmission, and a wheel hub mounted on the brake disc. To improve the interior space of existing electric vehicles, it is necessary to reduce the space occupied by the disc-wheel hub drive motor and transmission on the frame. Currently, it is necessary to reduce the axial length of the electric vehicle wheel drive system.

[0004] Therefore, the inventors believed there was a need to provide a wheel drive device for an electric vehicle with ideal compactness in the axial direction. Utility Model Content

[0005] To improve compactness, this application provides an in-wheel drive module system assembly for electric vehicles.

[0006] The electric vehicle in-wheel drive module system assembly provided in this application adopts the following technical solution:

[0007] An in-wheel drive module system assembly for an electric vehicle includes a wheel rim and a disc hub type drive motor disposed inside the wheel rim. The disc hub type drive motor includes a hub disc hub type drive motor, a gear reduction mechanism, an output main shaft, a front disc hub load end cover, a disc hub motor housing, a rear disc hub suspension end cover, a motor controller, a hub drive flange, a brake disc, and a brake caliper.

[0008] The front disc hub load end cover and the disc hub motor housing form a front cavity; the disc hub motor housing is provided with a middle cavity; the disc hub motor housing and the rear disc hub suspension end cover form a rear cavity; the gear reduction mechanism is built into the front cavity; the disc hub type drive motor is built into the middle cavity; and the motor controller is built into the rear cavity.

[0009] The hub-type drive motor includes a motor stator, a motor rotor, and a motor rotor shaft. The motor rotor shaft is a hollow shaft structure. A gear is provided at one end of the motor rotor shaft near the gear reduction mechanism. The motor rotor shaft drives the gear reduction mechanism to rotate through the gear. The gear reduction mechanism drives the output main shaft to rotate. The output main shaft passes through the motor rotor shaft and forms a sleeve-shaped composite structure with the motor rotor shaft.

[0010] The brake disc and the brake caliper form a braking system. The brake disc and the output spindle are fixedly connected, and the brake caliper is fixed on the front disc hub load end cover.

[0011] The output spindle is connected to the front disc hub load end cover and the rear hub suspension end cover via bearings.

[0012] By adopting the above technical solutions, the in-wheel drive module system assembly of electric vehicles achieves compactness and performance optimization of the drive unit through axial space integration design, sleeve-type transmission structure, and modular layout. The front cavity houses the gear reduction mechanism, the middle cavity contains the hub-type drive motor, and the rear cavity houses the motor controller. The three are connected in series along the axial direction within the hub motor housing, forming a compact modular structure of motor-reduction-control. Compared with the traditional drive unit where the motor and reduction device are arranged independently, this shortens the axial length and frees up space inside the vehicle frame.

[0013] The motor rotor shaft adopts a hollow design, with the output spindle passing through it, forming a rotor shaft-output spindle-coaxial sleeve structure. In traditional solutions, the motor rotor shaft and the input shaft of the reduction gear need to be axially aligned. This solution eliminates the axial overlap length through coaxial transmission, further reducing the axial dimension.

[0014] The motor rotor shaft directly drives the gear reduction mechanism via gears. The output end of the gear reduction mechanism is rigidly connected to the output main shaft, eliminating redundant links in the transmission chain and reducing energy loss during transmission. The output main shaft is connected to the front and rear end covers via bearings, forming a stable axial support system to prevent transmission noise or efficiency reduction caused by shaft misalignment.

[0015] Furthermore, the motor stator is installed inside the disc hub motor housing; the disc hub motor housing houses the motor rotor, which includes a rotor core and a motor rotor support. The rotor core is fixed to the motor rotor support, and the motor rotor shaft is fixedly connected to the motor rotor support. A rotary encoder is provided on the end of the motor rotor shaft away from the gear.

[0016] By adopting the above technical solution, the rotary encoder is installed on the motor rotor shaft away from the gear end, directly measuring the rotation angle and speed of the rotor core, avoiding interference from transmission errors in the gear reduction mechanism on the feedback signal. This improves the accuracy of motor position control, reduces the speed fluctuation range, and meets the needs of high-precision vector control and field weakening speed regulation scenarios such as dynamic torque matching during rapid acceleration of electric vehicles. The encoder signal is directly fed back to the motor controller, forming a short-path closed-loop system of rotor motion-signal acquisition-control adjustment. This shortens the motor response delay time, and under energy recovery conditions, it allows for more precise control of regenerative braking torque, improving the energy recovery rate.

[0017] Furthermore, the motor controller includes a filter device and a power module.

[0018] By adopting the above technical solutions, the filtering device can filter out high-frequency harmonics from the power input side, such as ripple current from the battery pack output or grid interference, avoiding problems such as motor torque fluctuations and increased heat generation caused by harmonics. It reduces the total harmonic distortion rate of the motor current, lowers stator winding losses, and extends the motor's service life. In conjunction with the power module's voltage regulation function, the filtering device can maintain stable motor input voltage during battery voltage fluctuations (such as fast charging) or sudden load changes (such as rapid acceleration).

[0019] Furthermore, the rear disc hub suspension end cap is provided with screw holes for docking with the vehicle suspension.

[0020] By adopting the above technical solution, compared to the traditional solution where the connection between the disc hub drive motor and the suspension requires 2-3 intermediate components, the screw holes in this solution can be directly bolted to components such as the lower control arm and shock absorber, avoiding the need for additional brackets or adapter plates required in traditional drive systems. This shortens the chassis assembly time of the single-wheel drive module, increases the cycle time of the vehicle production line, and reduces manufacturing energy consumption and costs.

[0021] Furthermore, the rotor core is composed of multiple rotor laminations stacked together, and slots are provided inside the rotor core for assembling magnets. The rotor core is also composed of multiple segments of rotor laminations stacked with oblique magnetic poles.

[0022] By adopting the above technical solution, the rotor laminations are configured with skewed magnetic poles. The magnetic pole axis of each lamination is offset circumferentially by a certain angle, causing a gradient change in the relative position of the rotor magnetic field and the stator slots, thus disrupting the periodicity of the cogging effect. The skewed magnetic poles and the superposition of multiple segments make the air gap magnetic field distribution closer to a sine wave, reducing the total harmonic distortion rate of the back electromotive force waveform and approaching an ideal sine wave. This reduces the harmonic losses of the stator windings, maintains the efficiency of the motor over a wide speed range, and especially improves efficiency in the high-speed, weak-field region.

[0023] Furthermore, the gear reduction mechanism includes a first gear section disposed at the tail end of the output spindle and a gear set that is drively connected to the first gear section and the gear end of the motor rotor shaft; the gear set includes a first transmission shaft rotatably mounted on the front cavity and parallel to the motor rotor shaft, a second gear mounted on the first transmission shaft and cooperating with the gear end of the motor rotor shaft, and a third gear mounted on the first transmission shaft and cooperating with the first gear section, wherein the second gear and the third gear are both axially locked to the first transmission shaft.

[0024] By adopting the above technical solution, the motor rotor shaft gear meshes with the second gear, and the third gear meshes with the first gear of the output main shaft, forming a two-stage parallel shaft reduction. By adjusting the gear ratio, the motor can operate in the high-efficiency range, adapting to the high torque requirements of electric vehicles at start-up and high-speed cruising. The two-stage gear transmission disperses the load of a single-stage reduction, and in conjunction with the rotor skew poles, reduces the torque fluctuation of the output main shaft, weakens the jerkiness during acceleration of the electric vehicle, and makes the drag torque during energy recovery smoother, improving driving comfort. The first drive shaft is arranged parallel to the motor rotor shaft, and the gear set is arranged radially in the front cavity. The second and third gears are pre-assembled with the first drive shaft as an independent gear set module, which can be installed as a whole in the front cavity, avoiding the axial space waste caused by the traditional multi-stage gear dispersed assembly.

[0025] Furthermore, the brake caliper employs a multi-cylinder piston hydraulic system.

[0026] By adopting the above technical solution, the multi-cylinder pistons are evenly distributed radially along the brake disc, resulting in a more balanced distribution of the clamping force between the brake pads and the brake disc. This avoids the brake pull problem caused by uneven pressure in traditional single-cylinder systems, improving vehicle stability during braking. The multi-cylinder pistons are synchronously driven through independent hydraulic channels, reducing hydraulic transmission delay and making the braking system respond more quickly to pedal actions. The heat dissipation structure design between the caliper cylinders expands the heat dissipation area, and combined with the balanced flow control of hydraulic oil, effectively reduces temperature accumulation during continuous braking, minimizing brake performance degradation due to high temperatures, making it more suitable for conditions requiring continuous braking, such as long downhill slopes.

[0027] Furthermore, the hub drive flange is fixedly connected to the output spindle, and the brake disc and the wheel rim are fixed to the hub drive flange by bolts.

[0028] By adopting the above technical solution, the hub drive flange is directly and rigidly connected to the output spindle, eliminating the flexible links in traditional multi-component transmissions and allowing the torque output by the motor to be transmitted to the wheel rim without loss. This avoids the risk of power interruption due to loose connections, and maintains stable driving force transmission, especially under complex road conditions such as bumpy roads, thus improving vehicle reliability. The brake disc and wheel rim are coaxially fixed to the flange with bolts, forming a compact integrated structure of the drive system and braking system in the axial direction. This eliminates the need for additional axial space to install independent brackets, effectively compressing the overall length of the drive module and meeting the space-constrained requirements of in-wheel drive systems.

[0029] Furthermore, one end of the output spindle is mounted on the front disc hub load end cover via a bearing, and the other end of the output spindle is mounted on the rear disc hub suspension end cover via a bearing.

[0030] By adopting the above technical solution, the bearings at both ends of the output spindle are anchored to the front and rear end covers respectively, forming a bridge-like double-support structure. This effectively resists radial loads caused by road bumps and axial loads caused by reaction forces during acceleration / braking, preventing the spindle from bending or shifting during high torque transmission and ensuring the accuracy and reliability of power transmission.

[0031] In summary, this application includes at least one of the following beneficial technical effects:

[0032] By employing a partitioned cavity layout, the gear reduction mechanism, hub-type drive motor, and motor controller are placed in the front, middle, and rear cavities respectively, forming a compact, modular structure connected in axial series. This significantly shortens the axial length compared to traditional independent arrangements, freeing up internal space within the vehicle frame. Simultaneously, the motor rotor shaft adopts a hollow design, forming a sleeve-like composite structure with the output main shaft. This eliminates the axial overlap of shaft connections in traditional transmissions, further optimizing space utilization and enhancing the adaptability of the drive module, meeting the compact layout requirements of electric vehicles.

[0033] The motor rotor shaft directly drives the gear reduction mechanism, combined with a two-stage parallel shaft gear set design, reducing transmission redundancy and optimizing torque output characteristics. This allows the motor to efficiently adapt to high starting torque and high-speed cruising conditions, reducing energy loss. The rotor core uses multi-segment slanted magnetic pole laminations to effectively suppress cogging torque pulsation, optimize back EMF waveform, and improve motor efficiency and power density. Multi-cylinder piston hydraulic brake calipers ensure uniform braking torque, rapid response, and strong resistance to thermal decay, comprehensively improving vehicle power and braking performance.

[0034] The screw holes on the rear disc wheel hub suspension end caps can directly connect to the vehicle suspension, reducing intermediate transition parts, simplifying the chassis assembly process, and improving production efficiency. The wheel hub drive flange, as a standardized interface, achieves rigid integration of the drive and braking systems, facilitating independent component replacement; the fit between the bearings at both ends of the output spindle and the end caps provides stable support while facilitating disassembly and assembly. Furthermore, the modular design of various components (such as gear sets and brake calipers) reduces R&D, production, and after-sales maintenance costs, enhancing product market competitiveness. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the overall structure of an in-wheel drive module system assembly for an electric vehicle according to an embodiment of this application.

[0036] Figure 2 This is a cross-sectional view of an in-wheel drive module system assembly for an electric vehicle according to an embodiment of this application. Figure 1 .

[0037] Figure 3 This is an exploded structural diagram of the front disc hub load end cover, disc hub motor housing, front cavity, and middle cavity of an embodiment of this application.

[0038] Figure 4 This is a schematic diagram of the overall structure of the gear reduction mechanism in the embodiments of this application.

[0039] Figure 5 This is an exploded view of the rotor core and rotor support of the motor rotor in the embodiments of this application.

[0040] Figure 6 This is a schematic diagram of the overall structure of the brake disc and brake caliper in the embodiments of this application.

[0041] Figure 7 This is a partial structural schematic diagram of the brake caliper in an embodiment of this application.

[0042] Figure 8 This is a cross-sectional view of an in-wheel drive module system assembly for an electric vehicle according to an embodiment of this application. Figure 2 .

[0043] Figure 9 This is an exploded structural diagram of the disc hub motor housing, the rear disc hub suspension end cover, and the rear cavity according to an embodiment of this application.

[0044] Explanation of reference numerals in the attached drawings: 0. Rim; 1. Hub disc, hub-type drive motor; 101. Motor stator; 102. Motor rotor; 1021. Rotor core; 10211. Slot; 1022. Motor rotor support; 103. Motor rotor shaft; 1031. Gear end; 104. Rotary encoder; 2. Gear reduction mechanism; 201. First gear section; 202. Gear set; 2021. First transmission shaft; 2022. Second... Gear; 2023, Third Gear; 3, Output Main Shaft; 31, Bearing; 4, Front Disc Hub Load End Cover; 401, Front Cavity; 5, Disc Hub Motor Housing; 501, Middle Cavity; 6, Rear Disc Hub Suspension End Cover; 61, Screw Hole; 62, Rear Cavity; 7, Motor Controller; 701, Filter Device; 702, Power Module; 8, Hub Drive Flange; 9, Brake Disc; 901, Cylinder Piston Hydraulic System; 10, Brake Caliper. Detailed Implementation

[0045] The following is in conjunction with the appendix Figure 1-9 This application will be described in further detail below.

[0046] This application discloses an in-wheel drive module system assembly for an electric vehicle. (Refer to...) Figure 1 and Figure 2 The electric vehicle in-wheel drive module system assembly includes a hub disc hub type drive motor 1, a gear reduction mechanism 2, an output main shaft 3, a front disc hub load end cover 4, a disc hub motor housing 5, a rear disc hub suspension end cover 6, a motor controller 7, a hub drive flange 8, a brake disc 9, and a brake caliper 10.

[0047] Reference Figure 2 and Figure 3 The front disc hub load end cover 4 and the disc hub motor housing 5 form a front cavity 401, and the gear reduction mechanism 2 is installed in the front cavity 401. The gear reduction mechanism 2 includes a first gear part 201 and a gear set 202. The first gear part 201 is located at the tail end of the output main shaft 3, and the gear set 202 is drively connected to the first gear part 201 and the gear end 1031 of the motor rotor shaft 103.

[0048] Reference Figure 3 and Figure 4 In this embodiment, the number of gear sets is preferably four. The gear set 202 includes a first drive shaft 2021, a second gear 2022, and a third gear 2023. The first drive shaft 2021 is rotatably mounted on the front cavity 401 and parallel to the motor rotor shaft 103. The second gear 2022 is mounted on the first drive shaft 2021 and engages with the gear end 1031 of the motor rotor shaft 103. The third gear 2023 is mounted on the first drive shaft 2021 and engages with the first gear section 201. Both the second gear 2022 and the third gear 2023 are axially locked to the first drive shaft 2021.

[0049] Reference Figure 2 and Figure 3 The disc hub motor housing 5 has a central cavity 501, and the disc hub type drive motor 1 is installed inside the central cavity 501. The disc hub type drive motor 1 includes a motor stator 101, a motor rotor 102, and a motor rotor shaft 103. The motor stator 101 is installed inside the disc hub motor housing 5, and the motor rotor 102 is disposed inside the disc hub motor housing 5. The motor rotor shaft 103 is a hollow shaft structure, and a rotary encoder 104 is provided on the motor rotor shaft 103 away from the gear end 1031.

[0050] Reference Figure 5 The motor rotor 102 includes a rotor core 1021 and a motor rotor 102 support. The rotor core 1021 is fixed on the motor rotor 102 support, and the motor rotor 102 support is fixedly connected to the motor rotor shaft 103. The rotor core 1021 is composed of multiple multi-segment rotor laminations with oblique magnetic poles stacked on top of each other. The rotor core 1021 has slots 10211 for assembling magnets.

[0051] A gear is provided at one end of the motor rotor shaft 103 near the gear reduction mechanism 2. The motor rotor shaft 103 drives the gear reduction mechanism 2 to rotate through the gear. The gear reduction mechanism 2 drives the output main shaft 3 to rotate. The output main shaft 3 passes through the motor rotor shaft 103, thus forming a sleeve-shaped composite structure with the motor rotor shaft 103.

[0052] Reference Figure 6 and Figure 7 The brake disc 9 and brake caliper 10 form the braking system. The brake disc 9 and output spindle 3 are fixedly connected. The output spindle 3 is connected to the front disc hub load end cover 4 and the rear hub suspension end cover via bearing 31. The brake caliper 10 adopts a multi-cylinder piston hydraulic system 901 and is fixed on the front disc hub load end cover 4. In this embodiment, there are four cylinder piston hydraulic systems 901.

[0053] Reference Figure 8 The hub drive flange 8 is fixedly connected to the output spindle 3, and the brake disc 9 and wheel rim 0 are fixed to the hub drive flange 8 by bolts. One end of the output spindle 3 is mounted on the front disc hub load end cover 4 via a bearing 31, and the other end of the output spindle 3 is mounted on the rear disc hub suspension end cover 6 via a bearing 31.

[0054] Reference Figure 3 and Figure 9 The rear disc hub suspension end cover 6 is provided with screw holes 61 for docking with the vehicle suspension. The disc hub motor housing 5 and the rear disc hub suspension end cover 6 form a rear cavity 62. The motor controller 7 is installed in the rear cavity 62. The motor controller 7 includes a filter device 701 and a power module 702.

[0055] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An in-wheel drive module system assembly for an electric vehicle, comprising a wheel rim and a disc-hub type drive motor disposed inside the wheel rim, characterized in that: The disc hub type drive motor includes a hub disc hub type drive motor, a gear reduction mechanism, an output main shaft, a front disc hub load end cover, a disc hub motor housing, a rear disc hub suspension end cover, a motor controller, a hub drive flange, a brake disc, and a brake caliper. The front disc hub load end cover and the disc hub motor housing form a front cavity, the disc hub motor housing is provided with a middle cavity, the disc hub motor housing and the rear disc hub suspension end cover form a rear cavity, the gear reduction mechanism is built into the front cavity, the disc hub type drive motor is built into the middle cavity, and the motor controller is built into the rear cavity; The hub-type drive motor includes a motor stator, a motor rotor, and a motor rotor shaft. The motor rotor shaft is a hollow shaft structure. A gear is provided at one end of the motor rotor shaft near the gear reduction mechanism. The motor rotor shaft drives the gear reduction mechanism to rotate through the gear. The gear reduction mechanism drives the output main shaft to rotate. The output main shaft passes through the motor rotor shaft and forms a sleeve-shaped composite structure with the motor rotor shaft. The brake disc and the brake caliper form a braking system. The brake disc and the output spindle are fixedly connected, and the brake caliper is fixed on the front disc hub load end cover. The output spindle is connected to the front disc hub load end cover and the rear disc hub suspension end cover via bearings.

2. An in-wheel drive module system assembly for an electric vehicle as set forth in claim 1, wherein, The motor stator is installed inside the disc hub motor housing; the disc hub motor housing contains a motor rotor, the motor rotor includes a rotor core and a motor rotor support, the rotor core is fixed on the motor rotor support, the motor rotor shaft is fixedly connected to the motor rotor support, and a rotary encoder is provided on the end of the motor rotor shaft away from the gear.

3. The electric vehicle in-wheel drive module system assembly according to claim 1, characterized in that, The motor controller includes a filter and a power module.

4. The electric vehicle in-wheel drive module system assembly of claim 1, wherein, The rear disc hub suspension end cap is provided with screw holes for docking with the vehicle suspension.

5. An in-wheel drive module system assembly for an electric vehicle as set forth in claim 2, wherein, The rotor core is composed of multiple rotor laminations stacked together. The rotor core has slots for assembling magnets. The rotor core is composed of multiple segments of rotor laminations stacked with oblique magnetic poles.

6. An electric vehicle in-wheel drive module system assembly according to claim 1, wherein, The gear reduction mechanism includes a first gear section disposed at the tail end of the output spindle and a gear set that is drively connected to the first gear section and the gear end of the motor rotor shaft; the gear set includes a first transmission shaft rotatably mounted on the front cavity and parallel to the motor rotor shaft, a second gear mounted on the first transmission shaft and cooperating with the gear end of the motor rotor shaft, and a third gear mounted on the first transmission shaft and cooperating with the first gear section, wherein the second gear and the third gear are both axially locked to the first transmission shaft.

7. An electric vehicle in-wheel drive module system assembly according to claim 1, wherein, The brake caliper uses a multi-cylinder piston hydraulic system.

8. An electric vehicle in-wheel drive module system assembly according to claim 1, wherein, The hub drive flange is fixedly connected to the output spindle, and the brake disc and the wheel rim are fixed to the hub drive flange by bolts.

9. The electric vehicle in-wheel drive module system assembly of claim 1, wherein, One end of the output spindle is mounted on the front disc hub load end cover via a bearing, and the other end of the output spindle is mounted on the rear disc hub suspension end cover via a bearing.

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