Three-phase three-layer multi-rotor electric motor structure and wheel hub electric motor using same

Abstract

Disclosed in the present invention is a three-phase three-layer multi-rotor electric motor structure, comprising three single-phase multi-rotor electric motor units axially mounted along a main shaft, each of which is of a 360-degree closed-loop structure composed of several small electric motors and has rotors and stators alternately arranged therein, wherein each stator is provided with semi-circular magnetic poles at two sides centered on a winding groove, and a permanent magnet rotor is coupled to the semi-circular magnetic poles of the adjacent stators at two sides to form a small electric motor; and the rotors of the three electric motor units are arranged in one-to-one correspondence in the axial direction of the electric motor and are coaxially connected in series by means of a rotor through shaft, and the directions of the magnetic field thereof are staggered by 120 degrees in sequence. The electric motor structure further comprises a main shaft gear disc fixed to the main shaft, and the main shaft gear disc not only acts as a timing gear to mesh with pinions arranged on rotor through shafts to drive the three electric motor units to operate continuously, but also acts as a thrust gear to output the electric motor torque. Also provided in the present invention is a wheel hub electric motor using the three-phase three-layer multi-rotor electric motor structure described above, which also has the advantages of higher rotational speed, higher efficiency, smaller size and lighter weight.

Description

A three-phase three-layer multi-rotor motor structure and a hub motor using the same Technical Field

[0001] The invention relates to a three-phase three-layer multi-rotor motor structure and a hub motor using the same. Background Art

[0002] Motors have been used as an existing technology for more than 100 years. However, the number of applications for motors is increasing, and higher requirements are being placed on them. Currently, the scientific research field is generally concerned with how to improve the performance of existing motors. The main research direction is to develop new motors that are small in size, light in weight, highly efficient, simple in structure, and adaptable to more different applications.

[0003] For existing high-power motors, increasing the motor's design speed is a simple way to reduce size, weight, and improve efficiency. However, due to the large rotor diameter and heavy weight of high-power motors, increasing the speed exponentially increases the centrifugal force within the rotor. For example, the maximum speed of an existing 200kW automotive motor is already 20,000 rpm, approaching the physical limit of the material. Therefore, achieving performance improvements at higher speeds is impossible.

[0004] In recent years, electric vehicles have experienced rapid development, and replacing fuel vehicles has become a major trend. Common in-wheel motors for electric vehicles include three-phase synchronous motors, three-phase asynchronous motors, electromagnetic motors, and switched reluctance motors. Their basic structure consists of a stator and a rotor, connected to the wheels via a drive shaft through a reduction gearbox and differential. The motor is typically mounted between the front and rear axles. For electric vehicles, reducing the weight of the drive unit translates to a higher thrust-to-weight ratio and less space in the passenger compartment. To maximize mileage using limited battery power, the motor must be lightweight, compact, and highly efficient. Therefore, increasing the motor speed is crucial. However, as previously analyzed, the maximum speed of in-wheel motors currently used in electric vehicles has reached 20,000 rpm, approaching the physical limits of the material, making it impossible to achieve performance improvements at higher speeds.

[0005] Of course, for electric motors, the smaller the rotor, the lower the centrifugal force, which allows for higher speeds. Therefore, the industry has designed multi-rotor motors to address this issue. While several patents exist for multi-rotor motors, all existing solutions suffer from various issues, making them impractical for practical application. Furthermore, for automobiles, especially small cars, unsprung mass is a significant factor affecting vehicle handling, stability, comfort, and energy consumption. Consequently, all current solutions involving in-wheel motors suffer from various issues, and a viable and effective solution has yet to be found. The primary reason is that at a speed of 100 kilometers per hour, the wheel speed is only a little over 1,000 revolutions per minute. In-wheel motors typically rotate synchronously with the wheels, making it unrealistic to produce a synchronous motor capable of delivering the torque required by typical vehicles at such low speeds. Even if in-wheel motors were employed, they would inevitably increase unsprung mass significantly, resulting in a reduction in various vehicle performance issues. In-wheel motors that avoid unsprung mass require a complex connection mechanism, resulting in high costs and low commercial value. Consequently, existing in-wheel motors and wheel-mounted motors are rarely used. Summary of the Invention

[0006] The purpose of the present invention is: on the one hand, the present invention is to address the shortcomings of the existing high-power motors mentioned in the background technology and provide a three-phase three-layer multi-rotor motor structure that can achieve higher speeds and higher working efficiency while being small in size, light in weight, and simple in structure, especially a single rotor with a short magnetic pole magnetic circuit, small magnetic resistance, and lower magnetic heat loss.

[0007] The technical solution of the present invention is: a three-phase, three-layer multi-rotor motor structure, including three single-phase multi-rotor motor groups installed axially along the main shaft of the motor and a main shaft gear plate fixed to the main shaft for outputting the motor torque; the characteristic is that each single-phase multi-rotor motor group is composed of corresponding rotors and stators installed in series in an alternating circumferential direction, wherein each stator is provided with a winding slot at the center for winding the stator coil, and corresponding semicircular magnetic poles are provided on both sides of the winding slot, respectively coupling two adjacent permanent magnet rotors, and each permanent magnet rotor is simultaneously coupled to the semicircular magnetic poles of the stators on both sides to form a small motor; the stator coils of the three single-phase multi-rotor motor groups are connected in a delta connection or a star connection;

[0008] The rotors of the three single-phase multi-rotor motor groups are arranged one by one along the axial direction of the motor, and the rotors of the three single-phase multi-rotor motor groups corresponding to each other in the axial direction are coaxially connected in series through the same rotor through-shaft, and their magnetic field directions are staggered by 120 degrees in sequence;

[0009] The main shaft gear disc is meshed with the pinion gear fixed on each rotor shaft, and when meshed, the magnetic field direction of the rotor in each single-phase multi-rotor motor group is consistent, so that the main shaft gear disc serves as the timing gear of the rotors of the three single-phase multi-rotor motor groups to limit the angular relationship corresponding to all rotor magnetic fields to drive the rotors of each single-phase multi-rotor motor group to operate continuously, and serves as the thrust gear of the rotors of the three single-phase multi-rotor motor groups to output motor torque.

[0010] Furthermore, in the present invention, at least one of the rotor shafts is equipped with an angular displacement sensor for detecting the magnetic field angle and angular velocity of the rotor in any single-phase multi-rotor motor group to control the speed of the entire motor, and the angular displacement sensor is one of a rotary transformer, an electromagnetic coil sensor and a Hall sensor.

[0011] Furthermore, the stator coils in the winding slots of the stator in the present invention are wound using flat wire windings.

[0012] Furthermore, the number of teeth of the pinion in the present invention is divisible by 3, and the number of teeth of the main shaft gear plate is divisible by X, where X=360 degrees / y, and y is the angle between two adjacent rotors on the circumference.

[0013] Another object of the present invention is to provide a hub motor using the above-mentioned three-phase three-layer multi-rotor motor structure, which can be used in electric vehicles as a power output component and has an advantage in speed.

[0014] As a practical application of the above-mentioned hub motor, we further designed its specific structure as follows:

[0015] On the basis of the three-phase three-layer multi-rotor motor structure, the hub motor also includes a motor housing for fixing the three single-phase multi-rotor motor groups and a motor end cover and a sprocket end cover respectively fastened to the motor housing from both sides. A sprocket oil chamber for sealing the main shaft sprocket is formed between the motor housing and the sprocket end cover. A main shaft is fixed at the center of the main shaft sprocket. One end of the main shaft is led out through a central shaft hole provided on the sprocket end cover to fix the hub fixing flange, and then the hub is fixed to the inner side of the automobile tire by the hub fixing flange, and the other end of the main shaft is supported in the motor housing by a bearing. The bearing includes a bearing inner ring and a bearing outer ring. The bearing inner ring is fixed on the main shaft, and the bearing outer ring is fixed to the motor housing, and the motor housing is fixed to the wheel fixing frame of the automobile. In the structural design of this hub motor, the vehicle body load-bearing force is directly transferred from the tire to the outer ring of the bearing and then acts on the wheel mounting frame. The motor housing, the outer ring of the bearing and the wheel mounting frame are fixed together. The motor housing only needs to provide the support force of the motor itself and does not bear the weight of the vehicle body. Therefore, the strength requirements of the motor housing are greatly reduced, the weight is reduced, and the structure is extremely simple.

[0016] Furthermore, in the above-mentioned hub motor of the present invention, the motor housing includes a supporting end wall for being fastened and fixed with the gear disc end cover to form the gear disc oil chamber, and an outer annular wall formed on the supporting end wall and an inner annular wall located on the inner side of the outer annular wall, an annular groove for embedding the three single-phase multi-rotor motor groups is formed between the inner annular wall and the outer annular wall; and an outer annular cooling water channel surrounding the annular groove is provided in the outer annular wall, and an inner annular cooling water channel surrounding the annular groove is provided on the inner annular wall, and the motor end cover is fastened to the motor housing to close the outer annular cooling water channel and the inner annular cooling water channel; and a water inlet is provided at the head end of the outer annular cooling water channel, and its end is connected to the head end of the inner annular cooling water channel, and a water outlet is provided at the end of the inner annular cooling water channel; or, a water inlet is provided at the head end of the inner annular cooling water channel, and its end is connected to the head end of the outer annular cooling water channel, and a water outlet is provided at the end of the outer annular cooling water channel; the bearing outer ring is fixed to the supporting end wall, and the wheel fixing frame is fixed to the inner annular wall.

[0017] In actual implementation, the outer circumference of the bearing outer ring can be formed with a plurality of positioning ears, each with corresponding positioning holes on the support end wall for receiving screws to secure the two. Furthermore, the outer circumference of the wheel mount, the inner circumference of the inner ring wall, and the inner circumference of the motor end cover can all be formed with a plurality of positioning ears corresponding to the positioning holes for receiving screws to secure the three.

[0018] Furthermore, in the above-mentioned hub motor of the present invention, the outer annular cooling water channel and the inner annular cooling water channel are both provided with a water inlet and a water outlet separated by a partition, wherein:

[0019] The water outlet of the outer annular cooling water channel is connected to the water inlet of the inner annular cooling water channel via a connecting water channel provided in the motor end cover, and the motor end cover is provided with an end cover water inlet hole connected to the water inlet of the outer annular cooling water channel and an end cover water outlet hole connected to the water outlet of the inner annular cooling water channel; or the water outlet of the inner annular cooling water channel is connected to the water inlet of the outer annular cooling water channel via a connecting water channel provided in the motor end cover, and the motor end cover is provided with an end cover water inlet hole connected to the water inlet of the inner annular cooling water channel and an end cover water outlet hole connected to the water outlet of the outer annular cooling water channel;

[0020] A cooling water cover is also fixed on the motor end cover, and the cooling water cover is provided with a water inlet interface connected to the water inlet hole of the end cover and a drainage interface connected to the water outlet hole of the end cover.

[0021] In the above-mentioned hub motor structural design of the present invention, cooling water channels are provided on both the inner and outer ring walls of the motor housing, so that both sides of the stator can obtain a larger heat dissipation area, achieving a good heat dissipation effect.

[0022] Furthermore, in the aforementioned in-wheel motor of the present invention, a hollow brake mounting post is provided at the center of the support end wall, the bearing is located inside the brake mounting post, and a brake chamber is formed between the support end wall, the inner annular wall of the motor housing, and the outer ring of the bearing. A drum brake is housed within the chamber, comprising a brake shoe and a brake drum. The brake shoe is secured to the brake mounting post, while the brake drum is secured to the main shaft and positioned around the brake shoe. The wheel mount serves as a brake chamber cover, secured to the motor housing to enclose the brake chamber. Clearly, the motor housing serves as both a motor mounting shell and a brake chamber, while the inner annular wall also serves as a load-bearing connection between the in-wheel motor and the vehicle frame or the frame's shock-absorbing connection device. The wheel mount serves as a brake chamber cover, secured to the motor housing to enclose the brake chamber.

[0023] Furthermore, in the aforementioned in-wheel motor of the present invention, the rotor shaft, on which the angular displacement sensor is mounted, is guided through an opening in the motor end cap. This provides an extremely simple structure and facilitates installation. Compared to the rotary transformer in existing magnetic induction motors, it is much easier to adjust the corresponding rotor angle.

[0024] Furthermore, in the aforementioned in-wheel motor of the present invention, the stator is provided with positioning protrusions at the top and bottom, while the outer surface of the inner annular wall is provided with positioning grooves that mate with the positioning protrusions at the bottom of the stator, and the inner surface of the outer annular wall is provided with positioning grooves that mate with the positioning protrusions at the top of the stator. This simplifies the manufacturing process for the motor housing, and the stator can be precisely positioned when embedded in the motor housing, providing excellent heat dissipation.

[0025] More preferably, the present invention further designs the following two air-cooling structure solutions for the hub motor:

[0026] One air-cooling structure solution is as follows: the wheel hub includes a wheel hub inner ring fixed to the wheel hub fixing flange and a wheel hub outer ring connected to the wheel hub inner ring by a plurality of connecting ribs; the wheel hub outer ring is located outside the outer ring wall, and a cooling air duct for cooling the stator is formed between the wheel hub outer ring and the outer ring wall; the cooling air duct inlet is located at the end of the wheel hub facing away from the wheel fixing frame, and the cooling air duct outlet is located at the end of the wheel hub where the wheel fixing frame is located; and a plurality of wheel hub fan blades are formed on the inner wall of the wheel hub outer ring, and a plurality of external heat dissipation blades are also formed on the outer peripheral surface of the outer ring wall;

[0027] An inner chamber of the brake chamber is formed between the inner periphery of the brake drum and the outer periphery of the brake mounting column, while an outer chamber of the brake chamber is formed between the outer periphery of the brake drum and the inner periphery of the inner annular wall. When the wheel fixing frame serves as a brake chamber cover, it is provided with a plurality of brake chamber air inlets communicating with the inner chamber, and a plurality of brake chamber air outlets communicating with the outer chamber; and the outer peripheral surface of the brake drum is provided with brake drum heat dissipation blades, and the inner peripheral surface of the inner annular wall is formed with a plurality of inner heat dissipation blades.

[0028] Another air-cooling structure solution is: the wheel hub includes a wheel hub inner ring fixed to the wheel hub fixing flange and a wheel hub outer ring connected to the wheel hub inner ring by a plurality of connecting ribs; the wheel hub outer ring is located outside the outer ring wall, and a cooling air duct is formed between the wheel hub outer ring and the outer ring wall for cooling the wheel hub outer ring and the outer ring wall; the cooling air duct inlet is located at the end of the wheel hub facing away from the wheel fixing frame, and the cooling air duct outlet is located at the end of the wheel hub where the wheel fixing frame is located; and a plurality of hub fan blades are formed on the inner wall of the wheel hub outer ring, and a plurality of external heat dissipation blades are also formed on the outer peripheral surface of the outer ring wall;

[0029] A brake chamber air inlet cover is sandwiched and fixed between the gear disc end cover and the supporting end wall, and an air inlet gap is left between the brake chamber air inlet cover and the supporting end wall. At the same time, a plurality of ventilation holes connecting the cooling air duct and the air inlet gap are provided on the outer periphery of the brake chamber air inlet cover. A brake chamber air inlet connecting the brake chamber and the air inlet gap is provided on the supporting end wall. When the wheel fixing frame serves as a brake chamber cover, a brake chamber air outlet connected to the brake chamber is provided thereon, and a brake drum heat dissipation blade is provided on the outer peripheral surface of the brake drum, and a plurality of inner heat dissipation blades are formed on the inner peripheral surface of the inner ring wall.

[0030] The advantages of the present invention are:

[0031] 1. The three-phase three-layer multi-rotor motor provided by the present invention has an advantage in that each single-phase multi-rotor motor group is a 360-degree closed loop structure composed of several small motors. The magnetic circuits of all individual small motors in the closed loop are completely closed without any magnetic field loss. The connection between adjacent stator coils in each single-phase multi-rotor motor group is extremely short, which reduces line loss, saves manufacturing materials for the entire motor, and simplifies the production process.

[0032] Specifically, because each stator in each single-phase multi-rotor motor serves as the magnetic pole for two adjacent rotors, the magnetic field generated by the motor acts simultaneously on both rotors when energized. This significantly shortens the magnetic field path compared to all existing motors, resulting in an extremely short magnetic circuit and minimal magnetic resistance, reducing magneto-thermal losses. Furthermore, the stator's open winding slot design allows the coils to be wound with thin copper flat wire, resulting in a higher slot fill factor than any other existing motor, reducing copper heat loss and thus improving motor efficiency. Compared to the most efficient motors of the same power rating, this motor saves over 50% in silicon steel and copper, and over 95% in silicon steel and copper compared to conventional motors. Furthermore, the stator coil winding process is simpler than any existing motor. The upper and lower sides of each stator pole contact the inner and outer walls of the motor housing, creating a large contact area that effectively improves heat dissipation and enhances the motor's heat dissipation. Other materials also save to varying degrees compared to conventional motors.

[0033] 2. The overall design of this invention significantly increases rotor speed, enabling the rated operating speed of the rotors comprising each single-phase multi-rotor motor to reach many times that of a high-power motor. All rotors are coupled to a single main shaft gear, ensuring the timing relationship between all rotor angles while simultaneously reducing speed and increasing torque, while also simplifying the overall motor structure.

[0034] 3. The overall design of the present invention is small in size and light in weight. Depending on the motor speed, power and torque requirements, the volume and weight of the present high-speed motor can be half, or even smaller and lighter, with a weight of only a few tenths of that of the conventional motor.

[0035] 4. The output speed and torque of the overall design of the present invention can be flexibly designed and configured with different small motors and spindle gear plates of different sizes according to needs, thereby achieving more flexible power and speed configuration. Compared with ordinary motors, it has a wide range of speeds and does not require a gearbox, which saves the cost of gearboxes and provides more customized options.

[0036] 5. The overall structural design of the present invention is compact and axially shorter than that of traditional motors. It is particularly suitable for special motor applications that have requirements for axial length, improving the flexibility of the motor in various applications and showing significant superiority in high-power motor applications. It is extremely suitable for various high-power motors and special scenarios, and also provides a wider range of choices for innovative products in electric vehicle hub motors and other fields.

[0037] 6. The most complicated process in the traditional motor manufacturing process is winding, especially for high-power motors, in which winding, wire embedding, and wire tying basically require manual operations. Even if small and medium-power motors can be produced with automatic winding equipment, the equipment is extremely expensive. Taking a 10-kilowatt winding production line as an example, it costs at least 10 million yuan, which is a huge investment. Moreover, a complete set of equipment can only produce one product, has no versatility, and still requires a lot of manpower. The winding process of the three-phase three-layer multi-rotor motor solution of the present invention is extremely simple. A winding equipment can be suitable for use with motors with power of tens to hundreds of kilowatts by replacing simple tooling. It has strong versatility and is very easy to achieve fully automatic production. The investment in a fully automatic production line will not exceed one-tenth of the traditional motor equipment, and unmanned production can be achieved.

[0038] 7. Based on the above three-phase three-layer multi-rotor motor structure, the present invention further designs a hub motor for electric vehicles, which effectively solves the following problems existing in the current hub motor solution:

[0039] A. First, due to the multi-rotor structure, the relative coupling area between the stator and rotor is large, resulting in high torque. Using an extremely small rotor, the speed can be increased to 50,000 to 100,000 rpm. This high-speed design enables the motor to convert electrical energy more efficiently, meeting the high energy efficiency requirements of high-power motors, thereby improving the energy efficiency of the entire vehicle. The motor itself is extremely lightweight, and the reduction ratio between the small rotor and the main shaft is approximately 20 times, greatly increasing the torque transmitted to the main shaft. Conversely, the simultaneous force applied by multiple rotors allows a large amount of stored energy to be recovered during deceleration, significantly reducing the need for brake mechanisms. Therefore, the bulky caliper brake discs used in existing vehicles are no longer required. The use of drum brakes reduces weight and makes the in-wheel motor structure extremely compact.

[0040] B. The in-wheel motor provided in this application, for example, a 50kW motor, can be controlled to weigh approximately 20 kg. The brake caliper and disc of a current B-class sedan typically weigh over 20 kg. Therefore, the in-wheel motor, drum brake mechanism, and caliper mechanism combined in this application have comparable unsprung mass. This lightweight design helps reduce overall vehicle mass, thereby improving energy efficiency and handling performance.

[0041] C. At the same time, this case also eliminates a large number of transmission system components in existing electric vehicles, reduces weight, and can save a lot of materials compared to traditional motors. This not only helps to reduce manufacturing costs, but also has a positive impact on sustainability and environmental protection, and is in line with the sustainable development trend of modern automobile manufacturing.

[0042] D. The motor's short axial length and large diameter make it very suitable for installation in existing car wheel hubs, freeing up valuable space in the passenger compartment and improving the space utilization rate of the vehicle.

[0043] By increasing the rotor speed, designing a large diameter and short axis, and achieving lightweight features, the hub motor in this case has demonstrated significant superiority in energy efficiency, space utilization, quality, and material usage, providing strong support for technological innovation in the field of electric vehicles.

[0044] In summary, this patented automotive hub motor is the only solution that can be widely promoted and applied. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0046] FIG1 is a schematic diagram of a three-dimensional structure of a universal motor using a three-phase three-layer multi-rotor motor structure of the present invention;

[0047] FIG2 is a schematic diagram of the three-dimensional assembly structure of FIG1 ;

[0048] FIG3 is a main cross-sectional view of FIG1 ;

[0049] FIG4 is a schematic diagram of the structure of a single-phase multi-rotor motor; ...

[0050] FIG5 is a schematic diagram of a separate three-dimensional structure of a stator in a small motor;

[0051] FIG6 is a schematic diagram showing the corresponding rotors of three single-phase multi-rotor motor groups connected in series via a single rotor through-shaft;

[0052] FIG7 is a schematic diagram of the magnetic field direction of the rotor magnet of the A-phase multi-rotor motor set on the leftmost side of FIG6 ;

[0053] FIG8 is a schematic diagram of the magnetic field direction of the rotor magnet of the B-phase multi-rotor motor group located in the middle of FIG6;

[0054] FIG9 is a schematic diagram of the magnetic field direction of the rotor magnet of the rightmost C-phase multi-rotor motor set in FIG6 ;

[0055] FIG10 is a schematic diagram of the assembly structure of the three single-phase multi-rotor motor groups in FIG1;

[0056] FIG11 is a cross-sectional view taken along line AA in FIG10 ;

[0057] FIG12 is a cross-sectional view taken along line BB in FIG10 ;

[0058] FIG13 is a cross-sectional view taken along the CC line in FIG10 ;

[0059] FIG14 is a schematic diagram of the positioning structure of a single-phase multi-rotor motor group within a motor housing;

[0060] FIG15 is a schematic diagram of the magnetic circuit of a conventional single-phase AC motor;

[0061] FIG16 is a schematic diagram of the magnetic circuit of a conventional three-phase AC motor;

[0062] Figure 17 is a schematic diagram of the magnetic circuit of the small motor in this case;

[0063] FIG18 is a schematic diagram of the three-dimensional structure of a hub motor using a three-phase three-layer multi-rotor motor structure;

[0064] FIG19 is a schematic diagram of the three-dimensional assembly structure of FIG18;

[0065] FIG20 is a main cross-sectional view of FIG18;

[0066] FIG21 is a schematic structural diagram of the cooling water channel inside the motor housing of the hub motor in FIG18 ;

[0067] FIG22 is a schematic diagram of the three-dimensional structure of a hub motor with an air-cooling structure;

[0068] FIG23 is a schematic diagram of the three-dimensional assembly structure of FIG22;

[0069] FIG24 is a main cross-sectional view of FIG22;

[0070] FIG25 is a schematic diagram of a three-dimensional assembly structure of another wheel hub motor with an air cooling structure;

[0071] FIG26 is a main cross-sectional view of FIG25.

[0072] In the figure: 1, main shaft; A, A-phase multi-rotor motor group; B, B-phase multi-rotor motor group; C, C-phase multi-rotor motor group; 2, main shaft gear disc; 3, rotor; 4, stator; 4a, winding groove; 4b, magnetic pole; 4c, positioning protrusion; 5, stator coil; H, magnetic circuit; 6, rotor through-shaft; 6a, pinion; 7, rotary transformer; 8, motor housing; 8a, supporting end wall; 8b, outer ring wall; 8c, inner ring wall; 8d, positioning groove; 9, motor end cover; 9a, connecting water channel; 9b, end cover water inlet hole; 9c, end cover water outlet hole; 10, gear disc end cover; 11, wheel hub fixing flange; 12, automobile tire; 13, wheel hub; 13a, wheel hub inner ring; 13b, wheel hub outer ring; 14, bearing; 14 a. Bearing inner ring; 14b. Bearing outer ring; 15. Wheel fixing frame; 16. Outer annular cooling water channel; 17. Inner annular cooling water channel; 18. Partition; 19. Cooling water cover; 19a. Water inlet interface; 19b. Drain interface; 20. Brake mounting column; 21. Brake chamber; 22. Brake shoe; 23. Brake drum; 24. Cooling air duct; 24a. Cooling air duct air inlet; 24b. Cooling air duct air outlet; 25. Hub fan blade; 26. External cooling blade; 27. Brake chamber air inlet; 28. Brake chamber air outlet; 29. ​​Internal cooling blade; 30. Brake chamber air inlet cover; 31. Air inlet gap; 32. Ventilation port; 33. Rotary transformer cover; 34. Brake drum cooling blade. DETAILED DESCRIPTION

[0073] Example 1: The following first describes a three-phase three-layer multi-rotor motor structure provided in this case with reference to FIG1 to FIG13 as follows:

[0074] As shown in Figure 1, a schematic diagram of the three-dimensional structure of a universal motor using a three-phase three-layer multi-rotor motor structure is shown. The motor has three single-phase multi-rotor motor groups, namely, A-phase multi-rotor motor group A, B-phase multi-rotor motor group B, and C-phase multi-rotor motor group C, which are axially mounted along the main shaft 1 of the motor, and a main shaft gear disc 2 fixed to the main shaft 1 for outputting the motor torque. As shown in Figures 2 and 3, as a universal motor, the three single-phase multi-rotor motor groups are all accommodated in a motor housing 8, and the two sides of the motor housing are respectively engaged with the motor end cover 9 and the gear disc end cover 10, wherein a gear disc oil chamber is formed between the motor housing 8 and the gear disc end cover 10 to seal the main shaft gear disc 2. The main shaft 1 is fixed to the center of the main shaft gear disc 2, and one end of the main shaft 1 extends through the central axis hole provided in the gear disc end cover 10.

[0075] Further in conjunction with Figures 4 and 5, each single-phase multi-rotor motor group is composed of corresponding rotors 3 and stators 4 installed in series in an alternating circumferential direction, wherein each stator 4 is provided with a winding slot 4a in the center for winding the stator coil 5, and corresponding semicircular magnetic poles 4b are provided on both sides of the winding slot 4a as the center, respectively coupling two adjacent permanent magnet rotors 3, and each permanent magnet rotor 3 is simultaneously coupled to the semicircular magnetic poles 4b of the stators 4 on both sides to form a small motor; the stator coils 5 of the three single-phase multi-rotor motor groups are connected in a triangle or star shape.

[0076] 6-9, the rotors 3 of the A-phase multi-rotor motor group A, the B-phase multi-rotor motor group B, and the C-phase multi-rotor motor group C are all arranged in a one-to-one correspondence along the axial direction of the motor, and the rotors 3 of the three corresponding single-phase multi-rotor motor groups in the axial direction are coaxially connected in series through the same rotor shaft 6, and their magnetic field directions are staggered by 120 degrees in sequence. In addition, in conjunction with Figures 2 and 3, in this embodiment, two rotor shafts 6 arranged at intervals on the circumference of the single-phase multi-rotor motor group are each installed with an angular displacement sensor for detecting the magnetic field angle of the rotor 3 to control the speed of the entire motor. The rotor shaft 6 on which the angular displacement sensor is installed is led out through the opening on the motor end cover 9 to install the angular displacement sensor, and the angular displacement sensor is an existing rotary transformer 7. After the rotary transformer 7 is installed, the rotary transformer cover 33 fixed to the motor end cover 9 is used to cover and protect the two rotary transformers 7.

[0077] As shown in Figures 2 and 3 , the main shaft gear 2 is drivingly coupled to each rotor shaft 6. Specifically, a pinion 6a is fixed to the rotor shaft 6 and meshes with the main shaft gear 2. When meshed, the magnetic field directions of the rotors 3 in each single-phase multi-rotor motor group remain consistent, as shown in Figures 11-13 . This allows the main shaft gear 2 to serve as both a timing gear for the rotors 3 of the three single-phase multi-rotor motor groups, defining the angular relationship between the magnetic fields of all the rotors 3 to drive the rotors 3 of each single-phase multi-rotor motor group to operate continuously, and a thrust gear for the rotors 3 of the three single-phase multi-rotor motor groups to output motor torque.

[0078] In this embodiment, the number of teeth of the pinion 6a is divisible by 3, and the number of teeth of the main shaft gear plate 2 is divisible by X, where X=360 degrees / y, and y is the angle between two adjacent rotors 3 on the circumference.

[0079] In this embodiment, the stator coils 5 within the winding slots 4a of the stator 4 are wound using rectangular wire. If thin copper rectangular wire is used, the slot fill factor is higher than any existing motor, reducing copper heat loss and thus improving motor efficiency. Compared to the most efficient existing motors of the same power, this motor uses over 50% less silicon steel and copper, and over 95% less silicon steel and copper than conventional motors.

[0080] As shown in FIG14 , the motor housing 8 includes a supporting end wall 8a for fastening with the gear disc end cover 10 to form the gear disc oil chamber, an outer annular wall 8b formed on the supporting end wall 8a, and an inner annular wall 8c located inwardly of the outer annular wall 8b. An annular groove for the three single-phase multi-rotor motor units is formed between the inner and outer annular walls 8c and 8b. For each single-phase multi-rotor motor unit, each stator 4 is provided with an arc-shaped positioning protrusion 4c at the top and bottom. The outer surface of the inner annular wall 8c is provided with an arc-shaped positioning groove 8d that matches the arc-shaped positioning protrusion 4c at the bottom of the stator. The inner surface of the outer annular wall 8b is provided with an arc-shaped positioning groove 8d that matches the arc-shaped positioning protrusion 4c at the top of the stator 4. This facilitates accurate and stable installation and positioning of the stator 4 and the motor unit within the motor housing 8.

[0081] As shown in Figures 15 to 17, since the two sides of the stator 4 in the small motor of each single-phase multi-rotor motor group in this embodiment serve as the magnetic poles of two adjacent rotors 3, after power is turned on, the force generating the magnetic field acts on the rotors 3 on both sides at the same time. Compared with all existing types of motors, the path of the magnetic field is greatly shortened, the magnetic circuit H is extremely short, the magnetic resistance is extremely small, and the magnetic heat loss is reduced. In comparison, the magnetic circuit H of the existing three-phase AC motor is longer, and the magnetic circuit H of the single-phase AC motor is the longest, both of which are longer than the magnetic circuit H of the small motor in this case.

[0082] Example 2: Further combined with Figures 18 to 20, a specific implementation method of a hub motor using the three-phase three-layer multi-rotor motor structure as mentioned above is shown. The three-phase three-layer multi-rotor motor structure can be referred to the description of Example 1. It also accommodates three single-phase multi-rotor motor groups, namely, the A-phase multi-rotor motor group A, the B-phase multi-rotor motor group B, and the C-phase multi-rotor motor group C, in the motor housing 8, and the motor end cover 9 and the gear disc end cover 10 are respectively fastened and fixed on both sides of the motor housing 8. A gear disc oil chamber for sealing the main shaft gear disc 2 is formed between the motor housing 8 and the gear disc end cover 10, and the center of the main shaft gear disc 2 is fixed to the main shaft 1. The characteristics of this hub motor are: one end of the main shaft 1 is led out through the central shaft hole provided on the gear plate end cover 10 to fix the hub fixing flange 11, and then the hub fixing flange 11 is fixed to the wheel hub 13 inside the automobile tire 12, while the other end of the main shaft 1 is supported by a bearing 14 and is arranged in the motor housing 8. The bearing 14 includes a bearing inner ring 14a and a bearing outer ring 14b. The bearing inner ring 14a is fixed on the main shaft 1, and the bearing outer ring 14b is fixed to the motor housing 8, and the motor housing 8 is further fixed to the wheel fixing frame 15 of the automobile.

[0083] In the structural design of this in-wheel motor, the vehicle body load-bearing force is directly transmitted from the vehicle tire 12 to the bearing outer ring 14b and then acts on the wheel fixing frame 15. The motor housing 8, the bearing outer ring 14b and the wheel fixing frame 15 are fixed together. The motor housing 8 only needs to provide the support force of the motor itself and does not bear the weight of the vehicle body. Therefore, the strength requirement of the motor housing 8 is greatly reduced, the weight is reduced, and the structure is extremely simple.

[0084] As further shown in Figures 18 to 21, the motor housing 8 in this embodiment includes a supporting end wall 8a for fastening and fixing with the gear disc end cover 10 to form the gear disc oil chamber, and an outer ring wall 8b formed on the supporting end wall 8a and an inner ring wall 8c located on the inner side of the outer ring wall 8b, and an annular groove for embedding three single-phase multi-rotor motor groups of phase A, phase B and phase C is formed between the inner ring wall 8c and the outer ring wall 8b; and an outer annular cooling water channel 16 surrounding the annular groove is provided in the outer ring wall 8b, and an inner annular cooling water channel 17 surrounding the annular groove is provided on the inner ring wall 8c, and the motor end cover 9 is fastened with the motor housing 8 to close the outer annular cooling water channel 16 and the inner annular cooling water channel 17; and a water inlet is provided at the head end of the outer annular cooling water channel 16, and its end is connected to the head end of the inner annular cooling water channel 17, and a water outlet is provided at the end of the inner annular cooling water channel 17.

[0085] In actual implementation, a plurality of positioning ears may be formed on the outer circumference of the bearing outer ring 14b, and corresponding positioning holes are provided on the positioning ears and the supporting end wall 8a for passing screws to fix the two.

[0086] Further referring to FIG19 and FIG21 , the outer annular cooling water channel 16 and the inner annular cooling water channel 17 are both provided with a water inlet and a water outlet separated by a partition 18 , wherein:

[0087] The outlet of outer annular cooling water channel 16 communicates with the inlet of inner annular cooling water channel 17 via a connecting water channel 9a disposed within motor end cover 9. Motor end cover 9 also includes an end cover water inlet 9b connected to the inlet of outer annular cooling water channel 16 and an end cover water outlet 9c connected to the outlet of inner annular cooling water channel 17. Furthermore, a cooling water cover 19 is secured to motor end cover 9 and includes an inlet port 19a connected to end cover water inlet 9b and a drain port 19b connected to end cover water outlet 9c. In the aforementioned hub motor design of the present invention, cooling water channels are provided on both the outer annular wall 8b and the inner annular wall 8c of the motor housing 8, providing a larger heat dissipation area on both sides of the stator 4 and achieving excellent heat dissipation.

[0088] As shown in Figures 19 and 20 , a hollow brake mounting post 20 is centrally located on the support end wall 8a of the in-wheel hub motor of this embodiment. The bearing 14 is located inside the brake mounting post 20. A brake chamber 21 is defined between the support end wall 8a, the inner annular wall 8c of the motor housing 8, and the outer race 14b of the bearing 14. Within this chamber is a drum brake comprising a brake shoe 22 and a brake drum 23. The brake shoe 22 is secured to the brake mounting post 20, while the brake drum 23 is secured to the spindle 1 and positioned around the brake shoe 22. The wheel mount 15 serves as a brake chamber cover, secured to the motor housing 8 to enclose the brake chamber 21. During actual mounting, the outer periphery of the wheel mount 15, the inner periphery of the inner annular wall 8c, and the inner periphery of the motor end cap 9 may be formed with a plurality of positioning ears corresponding to the positioning holes, for receiving screws to secure the three components.

[0089] Example 3: Combined with Figures 22 to 24, the cooling water channels (outer annular cooling water channel 16 and inner annular cooling water channel 17) in the motor housing 8 are eliminated on the basis of the hub motor of Example 2, and an air cooling structure is provided instead. The other overall structures can still refer to the description of Example 2.

[0090] The design features of this hub motor are as follows: the hub 13 includes a hub inner ring 13a fixed to the hub fixing flange 11 and a hub outer ring 13b connected to the hub inner ring 13a by a plurality of connecting ribs. The hub outer ring 13b is located outside the outer annular wall 8b, and a cooling air duct 24 for cooling the stator 4 is formed between the hub outer ring 13b and the outer annular wall 8b. The cooling air duct inlet 24a of the cooling air duct 24 is located at the end of the hub 13 facing away from the wheel fixing frame 15, while the cooling air duct outlet 24b is located at the end of the hub 13 where the wheel fixing frame 15 is located. In addition, a plurality of hub fan blades 25 are formed on the inner wall of the hub outer ring 13b, and a plurality of external heat dissipation blades 26 are also formed on the outer peripheral surface of the outer annular wall 8b.

[0091] The inner chamber of the brake chamber 21 is formed between the inner periphery of the brake drum 23 and the outer periphery of the brake mounting column 20, while the outer chamber of the brake chamber 21 is formed between the outer periphery of the brake drum 23 and the inner periphery of the inner annular wall 8c. When the wheel fixing frame 15 serves as a brake chamber cover, it is provided with a plurality of brake chamber air inlets 27 communicating with the inner chamber, and a plurality of brake chamber air outlets 28 communicating with the outer chamber; and the outer peripheral surface of the brake drum 23 is provided with brake drum heat dissipation blades 34, and the inner peripheral surface of the inner annular wall 8c is formed with a plurality of inner heat dissipation blades 29.

[0092] Obviously, this embodiment adds an air cooling structure to ensure effective heat dissipation for the three single-phase multi-rotor motor groups in the motor housing 8 and the brake in the brake chamber.

[0093] Example 4: As shown in Figures 25 and 26, the cooling water channels (outer annular cooling water channel 16 and inner annular cooling water channel 17) in the motor housing 8 are eliminated based on the hub motor of Example 2, and another hub motor with an air-cooling structure is provided. The other overall structures can still refer to the description of Example 2.

[0094] The wheel hub 13 includes a wheel hub inner ring 13a fixed to the wheel hub fixing flange 11 and a wheel hub outer ring 13b connected to the wheel hub inner ring 13a via a plurality of connecting ribs. The wheel hub outer ring 13b is located outside the outer annular wall 8b, and a cooling air duct 24 for cooling the stator 4 is formed between the wheel hub outer ring 13b and the outer annular wall 8b. The cooling air duct inlet 24a of the cooling air duct 24 is located at the end of the wheel hub 13 facing away from the wheel fixing frame 15, and the cooling air duct outlet 24b is located at the end of the wheel hub 13 where the wheel fixing frame 15 is located. In addition, a plurality of hub fan blades 25 are formed on the inner wall of the wheel hub outer ring 13b, and a plurality of external heat dissipation blades 26 are also formed on the outer peripheral surface of the outer annular wall 8b.

[0095] A brake chamber air inlet cover 30 is sandwiched and fixed between the sprocket end cover 10 and the support end wall 8a, and an air inlet gap 31 is left between the brake chamber air inlet cover 30 and the support end wall 8a. At the same time, a plurality of vents 32 connecting the cooling air duct 24 and the air inlet gap 31 are provided on the outer periphery of the brake chamber air inlet cover 30. A brake chamber air inlet 27 connecting the brake chamber 21 and the air inlet gap 31 is opened on the support end wall 8a. When the wheel fixing frame 15 serves as a brake chamber cover, it is provided with a brake chamber air outlet 28 connected to the brake chamber 21, and the outer peripheral surface of the brake drum 23 is provided with brake drum heat dissipation blades 34, and the inner peripheral surface of the inner ring wall 8c is formed with a plurality of inner heat dissipation blades 29.

[0096] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the present invention and implement it accordingly. They are not intended to limit the scope of protection of the present invention. Any modifications made within the spirit of the main technical solution of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A three-phase three-layer multi-rotor motor structure, characterized in that The invention comprises three single-phase multi-rotor motor groups axially mounted along the main shaft (1) of the motor and a main shaft gear disc (2) fixed to the main shaft (1) for outputting the motor torque; each single-phase multi-rotor motor group is formed by corresponding rotors (3) and stators (4) being alternately mounted in series in the circumferential direction, wherein a winding slot (4a) is provided at the center of each stator (4) for winding a stator coil (5); corresponding semicircular magnetic poles (4b) are provided on both sides of the winding slot (4a) as the center, respectively coupling two adjacent permanent magnet rotors (3); each permanent magnet rotor (3) is simultaneously coupled to the semicircular magnetic poles (4b) of the stators (4) on both sides to form a small motor; the stator coils (5) of the three single-phase multi-rotor motor groups are connected in a triangle or star shape; The rotors (3) of the three single-phase multi-rotor motor groups are all arranged in a one-to-one correspondence along the motor axial direction, and the rotors (3) of the three single-phase multi-rotor motor groups corresponding in the axial direction are coaxially connected in series via the same rotor through-shaft (6), and their magnetic field directions are staggered by 120 degrees in sequence; The main shaft gear disc (2) is meshed with the pinion gear (6a) fixed on each rotor shaft (6), and when meshed, the magnetic field directions of the rotors (3) in each single-phase multi-rotor motor group are all kept consistent, so that the main shaft gear disc (2) serves as a timing gear for the rotors (3) of the three single-phase multi-rotor motor groups to limit the angular relationship that the magnetic fields of all the rotors (3) need to correspond to, so as to drive the rotors (3) of each single-phase multi-rotor motor group to operate continuously, and also serves as a thrust gear for the rotors (3) of the three single-phase multi-rotor motor groups to output motor torque.

2. A three-phase three-layer multi-rotor motor structure according to claim 1, characterized in that An angular displacement sensor for detecting the magnetic field angle and angular velocity of the rotor (3) in any single-phase multi-rotor motor group is installed on at least one of the rotor shafts (6) to control the rotation speed of the entire motor, and the angular displacement sensor is one of a rotary transformer (7), an electromagnetic coil sensor, and a Hall sensor.

3. The three-phase three-layer multi-rotor motor structure according to claim 1 is characterized in that The stator coil (5) in the winding slot (4a) of the stator (4) is wound using a flat wire winding.

4. The three-phase three-layer multi-rotor motor structure according to claim 1 is characterized in that The number of teeth of the pinion (6a) is divisible by 3, and the number of teeth of the main shaft gear disc (2) is divisible by X, where X=360 degrees / y, and y is the angle between two adjacent rotors (3) on the circumference.

5. A hub motor using the three-phase three-layer multi-rotor motor structure according to any one of claims 1 to 4.

6. The hub motor according to claim 5, characterized in that The motor housing (8) is used to fix the three single-phase multi-rotor motor groups, and a motor end cover (9) and a gear end cover (10) are respectively fastened and fixed to the motor housing (8) from both sides. A gear oil chamber for sealing the main shaft gear (2) is formed between the motor housing (8) and the gear end cover (10). The main shaft (1) is fixed at the center of the main shaft gear (2). One end of the main shaft (1) is led out through a central shaft hole provided on the gear end cover (10) to fix the hub fixing flange (11). The wheel hub fixing flange (11) is then fixed to the wheel hub (13) on the inner side of the automobile tire (12), and the other end of the main shaft (1) is supported by a bearing (14) and is arranged in the motor housing (8). The bearing (14) includes a bearing inner ring (14a) and a bearing outer ring (14b). The bearing inner ring (14a) is fixed to the main shaft (1), and the bearing outer ring (14b) is fixed to the motor housing (8). The motor housing (8) is further fixed to the wheel fixing frame (15) of the automobile.

7. The hub motor according to claim 6, characterized in that The motor housing (8) includes a supporting end wall (8a) for fastening and fixing with a gear disc end cover (10) to form the gear disc oil chamber, an outer ring wall (8b) formed on the supporting end wall (8a), and an inner ring wall (8c) located on the inner side of the outer ring wall (8b), wherein an annular groove for embedding the three single-phase multi-rotor motor groups is formed between the inner ring wall (8c) and the outer ring wall (8b); and an outer annular cooling water channel (16) surrounding the annular groove is provided in the outer ring wall (8b), and an inner annular cooling water channel (17) surrounding the annular groove is provided on the inner ring wall (8c). The motor end cover (9) is connected to the motor housing (8). The outer annular cooling water channel (16) and the inner annular cooling water channel (17) are fastened together to close the outer annular cooling water channel (16); and the outer annular cooling water channel (16) is provided with a water inlet at its head end, and its tail end is connected to the head end of the inner annular cooling water channel (17), while the tail end of the inner annular cooling water channel (17) is provided with a water outlet; or, the inner annular cooling water channel (17) is provided with a water inlet at its head end, and its tail end is connected to the head end of the outer annular cooling water channel (16), while the tail end of the outer annular cooling water channel (16) is provided with a water outlet; the bearing outer ring (14b) is fixed to the support end wall (8a), and the wheel fixing frame (15) is fixed to the inner annular wall (8c).

8. The hub motor according to claim 7, characterized in that The outer annular cooling water channel (16) and the inner annular cooling water channel (17) are both provided with a water inlet and a water outlet separated by a partition (18), wherein: The water outlet of the outer annular cooling water channel (16) is connected to the water inlet of the inner annular cooling water channel (17) through a connecting water channel (9a) provided in the motor end cover (9), and the motor end cover (9) is provided with an end cover water inlet hole (9b) connected to the water inlet of the outer annular cooling water channel (16) and an end cover water outlet hole (9c) connected to the water outlet of the inner annular cooling water channel (17); or the water outlet of the inner annular cooling water channel (17) is connected to the water inlet of the outer annular cooling water channel (16) through a connecting water channel provided in the motor end cover (9), and the motor end cover (9) is provided with an end cover water inlet hole connected to the water inlet of the inner annular cooling water channel (17) and an end cover water outlet hole connected to the water outlet of the outer annular cooling water channel (16); A cooling water cover (19) is also fixed on the motor end cover (9), and the cooling water cover (19) is provided with a water inlet interface (19a) connected to the end cover water inlet hole (9b) and a drainage interface (19b) connected to the end cover water outlet hole (9c).

9. The hub motor according to claim 7, characterized in that A hollow brake mounting column (20) is provided at the center of the support end wall (8a), and the bearing (14) is located inside the brake mounting column (20). A brake chamber (21) is formed between the support end wall (8a), the inner ring wall (8c) and the bearing outer ring (14b) of the bearing (14) of the motor housing (8), and a drum brake is provided therein, which includes a brake shoe (22) and a brake drum (23). The brake shoe (22) is fixed on the brake mounting column (20), and the brake drum (23) is fixed to the main shaft (1) and is located outside the brake shoe (22); the wheel fixing frame (15) is fixed to the motor housing (8) as a brake chamber cover to close the brake chamber (21).

10. The hub motor according to claim 6, characterized in that The top and bottom of the stator (4) are provided with positioning protrusions (4c), the outer wall surface of the inner ring wall (8c) is provided with a positioning groove (8d) matching the positioning protrusion (4c) at the bottom of the stator (4), and the inner wall surface of the outer ring wall (8b) is provided with a positioning groove (8d) matching the positioning protrusion (4c) at the top of the stator (4).

11. The hub motor according to claim 9, characterized in that The wheel hub (13) includes a wheel hub inner ring (13a) fixed to the wheel hub fixing flange (11) and a wheel hub outer ring (13b) connected to the wheel hub inner ring (13a) via a plurality of connecting ribs. The wheel hub outer ring (13b) is located outside the outer ring wall (8b), and a cooling air duct (24) for cooling the stator (4) is formed between the wheel hub outer ring (13b) and the outer ring wall (8b). The cooling air duct inlet (24a) of the cooling air duct (24) is located at the end of the wheel hub (13) facing away from the wheel fixing frame (15), and the cooling air duct outlet (24b) is located at the end of the wheel hub (13) where the wheel fixing frame (15) is located. In addition, a plurality of wheel hub fan blades (25) are formed on the inner wall of the wheel hub outer ring (13b), and a plurality of external heat dissipation blades (26) are also formed on the outer peripheral surface of the outer ring wall (8b). The inner periphery of the brake drum (23) and the outer periphery of the brake mounting column (20) form an inner chamber of the brake chamber (21), while the outer periphery of the brake drum (23) and the inner periphery of the inner annular wall (8c) form an outer chamber of the brake chamber (21). When the wheel fixing frame (15) serves as a brake chamber cover, it is provided with a plurality of brake chamber air inlets (27) communicating with the inner chamber, and a plurality of brake chamber air outlets (28) communicating with the outer chamber; and the outer peripheral surface of the brake drum (23) is provided with brake drum heat dissipation blades (34), while the inner peripheral surface of the inner annular wall (8c) is formed with a plurality of inner heat dissipation blades (29).

12. The hub motor according to claim 9, characterized in that The wheel hub (13) includes a wheel hub inner ring (13a) fixed to the wheel hub fixing flange (11) and a wheel hub outer ring (13b) connected to the wheel hub inner ring (13a) via a plurality of connecting ribs. The wheel hub outer ring (13b) is located outside the outer ring wall (8b), and a cooling air duct (24) for cooling the stator (4) is formed between the wheel hub outer ring (13b) and the outer ring wall (8b). The cooling air duct inlet (24a) of the cooling air duct (24) is located at the end of the wheel hub (13) facing away from the wheel fixing frame (15), and the cooling air duct outlet (24b) is located at the end of the wheel hub (13) where the wheel fixing frame (15) is located. In addition, a plurality of wheel hub fan blades (25) are formed on the inner wall of the wheel hub outer ring (13b), and a plurality of external heat dissipation blades (26) are also formed on the outer peripheral surface of the outer ring wall (8b). A brake chamber air inlet cover (30) is fixed between the toothed disc end cover (10) and the support end wall (8a), and an air inlet gap (31) is left between the brake chamber air inlet cover (30) and the support end wall (8a). At the same time, a plurality of ventilation holes (32) are provided on the outer periphery of the brake chamber air inlet cover (30) for connecting the cooling air duct (24) and the air inlet gap (31). A brake chamber air inlet (27) for connecting the brake chamber (21) and the air inlet gap (31) is provided on the support end wall (8a). When the wheel fixing frame (15) serves as a brake chamber cover, a brake chamber air outlet (28) is provided on it for connecting with the brake chamber (21), and a brake drum heat dissipation blade (34) is provided on the outer peripheral surface of the brake drum (23), and a plurality of inner heat dissipation blades (29) are formed on the inner peripheral surface of the inner ring wall (8c).

Images