Hub motor

Abstract

The invention provides a wheel hub motor which comprises a main shaft serving as a mounting carrier and used for being connected with a vehicle frame; the hub shell serves as an output end and is used for being connected with a wheel, and the hub shell is rotationally installed on the main shaft; the stator is positioned in the hub shell and is fixed on the main shaft; the rotor is located in the hub shell and can rotate around the stator; the speed reduction assembly is arranged between the rotor and the hub shell and used for transmitting power of the rotor to the hub shell and driving the hub shell to rotate; and the iron core of the stator and / or the rotor is made of an amorphous material. The novel hub motor is compact in structure, small in size, high in motor efficiency, large in efficiency platform interval and good in using effect.

Description

Technical Field

[0001] The invention relates to a motor, in particular to a hub motor. Background Art

[0002] An electric power-assisted bicycle is composed of an ordinary bicycle with a drive motor added. The drive motor is powered by a battery installed on the frame. The drive motor rotates to drive the electric power-assisted bicycle. The drive motor is generally installed in the front wheel hub or the rear wheel hub, so it is also called a hub motor. As the core power component of an electric power-assisted bicycle, the development of hub motors in the industry is currently dominated by miniaturization, high power, and high output torque.

[0003] The stator of the existing hub motor is a silicon steel core, which is stamped from a steel strip and bonded together through laminations and heat-cured. The manufacturing process is complicated and the production line is long. The silicon steel core will have large losses during use, which mainly include hysteresis loss and eddy current loss. The hysteresis loss is the loss caused by the non-smooth arrangement of the molecular magnetic moments when the iron core is magnetized reversed, while the eddy current loss is the energy loss caused by the heat generated by the eddy current induced in the iron core in the alternating magnetic field.

[0004] The existing iron core has the problems of complex manufacturing process, high cost, serious loss and low efficiency. Therefore, it is urgent to develop a new type of iron core and motor to overcome the above problems and meet the requirements of lightweight and high efficiency. Summary of the invention

[0005] Technical issues to be solved The technical problem to be solved by the present invention is to provide a hub motor with compact structure, small volume, simple manufacturing process, low loss and high efficiency.

[0006] Technical solutions to the problem The present invention provides a hub motor, comprising: The main shaft 1 is used as a mounting carrier and is used to connect with the frame; A wheel hub shell 2, serving as an output end and used to connect with a wheel, wherein the wheel hub shell 2 is rotatably mounted on the main shaft 1; The stator 3 is located in the wheel hub shell 2 and fixed on the main shaft 1; A rotor 4, located in the hub shell 2 and capable of rotating around the stator 3; A reduction assembly, disposed between the rotor 4 and the wheel hub shell 2, for transmitting the power of the rotor to the wheel hub shell 2 and driving the wheel hub shell 2 to rotate; The iron core of the stator 3 and / or the rotor 4 is made of amorphous material; The rated speed of the hub shell 2 is 180RPM-420RPM, and the transmission ratio of the reduction assembly is greater than or equal to 6 and less than or equal to 14.

[0007] Furthermore, the transmission ratio of the planetary reduction assembly is greater than or equal to 9 and less than or equal to 12.5.

[0008] Furthermore, the transmission ratio of the planetary reduction assembly is greater than or equal to 9 and less than or equal to 12.

[0009] Furthermore, the transmission ratio of the planetary reduction assembly is 115 / 12.

[0010] Furthermore, the rated torque of the wheel hub shell 2 is 8NM-16NM.

[0011] Furthermore, the planetary reduction assembly is a two-stage or three-stage reduction assembly.

[0012] Furthermore, the planetary reduction assembly includes a central gear fixed to the rotor, a ring gear fixed to the inner wall of the hub shell, a planetary carrier fixed to the main shaft, and a plurality of planetary gears arranged on the planetary carrier. The planetary gears are double gears and have a large gear end meshing with the central gear and a small gear end meshing with the ring gear, thereby forming a secondary reduction.

[0013] Furthermore, the number of teeth of the central gear is 18, the number of teeth of the large gear end of the planetary gear is 45, the number of teeth of the small gear end is 18, and the number of teeth of the ring gear is 69.

[0014] Furthermore, the 80% efficiency platform of the hub motor accounts for: ; Among them, N1 is the torque range when the motor efficiency is greater than or equal to 80%, and N2 is the entire torque range of the motor.

[0015] Furthermore, the maximum efficiency of the hub motor is greater than or equal to 85%.

[0016] Furthermore, the diameter of the wheel hub shell is 110 mm-145 mm, and the axial width of the wheel hub shell is 80 mm-120 mm.

[0017] Beneficial Effects The hub motor of the present invention has an iron core made of amorphous material and optimizes the transmission ratio, which improves the efficiency of the motor and widens the efficiency platform range, so that the motor can maintain a high working efficiency under different working conditions, which not only reduces energy consumption and brings longer cruising range, but also improves the stability and reliability of the motor in the full range of working conditions, making the driving control of the whole vehicle smoother; at the same time, under the premise of meeting the design requirements, the volume of the product is greatly reduced, the installation space is reduced, which is conducive to the installation and layout on the vehicle, reduces the production cost, and enhances the market competitiveness, which makes the motor show excellent performance in a variety of application scenarios and meets the urgent needs of modern transportation for high efficiency and low energy consumption; in addition, the use of amorphous materials also brings good thermal stability and corrosion resistance, small iron core loss, further extends the service life of the motor, reduces maintenance costs, and brings users a better experience; the hub motor of the present invention has a compact structure, small size, high working efficiency, a large efficiency platform range, and a good use effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the hub motor of the present invention; Figure 2 It is the efficiency curve diagram of the new and old motors at the first speed and the first transmission ratio; Figure 3 The efficiency curves of the new and old motors at the second speed and the first transmission ratio; Figure 4 This is the efficiency curve of the new and old motors at the third speed and the first transmission ratio; Figure 5 The efficiency curves of the new and old motors at the fourth speed and the second transmission ratio; Figure 6 This is the efficiency curve of the new and old motors at the fifth speed and the second transmission ratio; Figure 7 The efficiency curves of the new and old motors at the sixth speed and the second transmission ratio; Figure 8 This is the efficiency curve of the new and old motors at the seventh speed and different transmission ratios; In the figure: 1, main shaft, 11, rotor bracket, 2, hub shell, 3, stator, 31, stator bracket, 4, rotor, 41, planet carrier, 42, central gear, 43, planetary gear, 44, ring gear. DETAILED DESCRIPTION

[0019] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0020] See also Figure 1The present invention provides a hub motor, which includes a main shaft 1, a hub shell 2, a stator 3, a rotor 4 and a planetary reduction assembly. The cross section of the hub shell 2 is circular, forming a cylindrical structure as a whole. The interior of the hub shell 2 is hollow, forming an installation cavity for installing the stator 3, the rotor 4 and the planetary reduction assembly. The main shaft 1 is coaxially arranged with the hub shell 2. The main shaft 1 is rotatably mounted on the hub shell 2 through a plurality of bearings. Both ends of the main shaft 1 extend to the outside of the hub shell 2 and serve as installation ends for fixing on a vehicle frame. That is, when in use, the main shaft 1 is in a fixed state and the hub shell 2 is in a rotating state. Therefore, it can be understood that the hub shell 2 is rotatably mounted on the main shaft 1. The hub shell 2 is connected to the tire through a steel ring, which is used to drive the tire to rotate and realize power-assisted driving. A stator bracket 31 is arranged in the hub shell 2. The stator bracket 31 is cylindrical as a whole, coaxial with the main shaft 1, and one end of the stator bracket 31 extends radially inward and is connected to the main shaft 1. The shaft 1 is fixedly connected, and the outer wall of the stator bracket 31 forms a cylindrical mounting portion, and an annular protrusion is provided at one end of the mounting portion to form a leaning surface for axial limitation; a stator 3, that is, an iron core, is provided on the outer sleeve of the stator bracket 31. The stator is cylindrical as a whole, and a mounting hole is opened in the center of the stator. It is sleeved on the cylindrical mounting portion of the stator bracket 31, and one end of the stator contacts with the annular protrusion to achieve axial limitation, thereby achieving accurate installation of the stator; at the same time, a rotor bracket 11 is rotatably installed on the main shaft 1 through a bearing, and the edge of the rotor bracket 11 is bent 90 degrees toward the stator direction to form a rotor mounting portion. The rotor mounting portion is cylindrical, coaxial with the stator, and located outside the stator 3. A rotor 4 is fixed on the inner wall of the cylindrical rotor mounting portion. The rotor is cylindrical, a magnet, coaxial with the stator, and located outside the stator. When the stator 3 is energized, it can generate electromagnetic force and drive the rotor 4 to rotate;The planetary reduction assembly is arranged between the rotor 4 and the hub shell 2, and the planetary reduction assembly includes a central gear 42, planetary gears 43 and a ring gear 44. The central gear 42 is a sun gear, which is rigidly fixed to the end of the rotor 4 and is coaxial with the rotor 4. Both ends of the central gear 42 are penetrated with central holes, which can allow the main shaft 1 to pass through. At the same time, a planet carrier 41 is arranged in the hub shell 2. There are multiple planetary gears 43 and they are evenly distributed on the planet carrier 41 in the circumferential direction. Specifically, the axis of the planet carrier 41 is coaxial with the main shaft 1, and a through hole is opened in the center thereof for allowing the main shaft 1 to pass through. A key is arranged between the through hole and the main shaft 1 for connecting with the main shaft 1, that is, the planet carrier 41 and the main shaft 1. Fixedly connected, and can rotate or be fixed synchronously with the main shaft, a planetary shaft is arranged at one end of the planetary carrier 41, the axis of the planetary shaft is parallel to the rotation axis of the stator 3, and the planetary gear 43 is rotatably mounted on the planetary shaft through a bearing. In this embodiment, the planetary gear 43 is a double gear, that is, it includes a coaxial large gear and a small gear, wherein the large gear of the planetary gear 43 is meshed with the central gear 42, and the number of teeth of the large gear of the planetary gear 43 is greater than the number of teeth of the central gear 42, forming a primary reduction, and the small gear of the planetary gear 43 is meshed with the ring gear 44 fixed to the inner wall of the hub shell 2, and the number of teeth of the small gear of the planetary gear 43 is less than the number of teeth of the ring gear 44, forming a secondary reduction. ;

[0021] During operation, both ends of the main shaft 1 are fixed on a vehicle frame (not shown in the figure), the outer side of the wheel hub shell 2 is connected to a rim through spokes, a tire is installed on the rim, the stator 3 is energized, and the rotor 4 is driven to rotate, the rotor 4 drives the rotor bracket 31 to rotate, so that the central gear 42 on the rotor bracket 31 rotates, the central gear 42 rotates to drive the planetary gear 43 to rotate, the planetary gear 43 drives the ring gear 44 to rotate, and since the ring gear 44 is rigidly fixed to the inner wall of the wheel hub shell 2, the rotation of the wheel hub shell 2 is realized; the above-mentioned planetary gear 43 is a double gear, and therefore, two-stage reduction can be achieved, the transmission ratio is large, the output torque is high and the output is stable.

[0022] In the present application, the stator 3 is made of amorphous material. Amorphous alloy is also called metallic glass, which is a green engineering material with excellent soft magnetic properties. It adopts plane flow casting technology, has a short metallurgical process, and saves 80% energy compared with ordinary steel manufacturing process. It has good physical properties, mechanical properties and chemical properties. For physical properties, it has a low melting point, low electrical conductivity and low thermal conductivity; for mechanical properties, it has high strength, good hardness, scratch resistance, no plastic deformation, and a high elastic limit; for chemical properties, it has high corrosion resistance.

[0023] The output speed of the hub motor of the present application, that is, the output speed of the hub shell 2 is 180RPM-420RPM, wherein the transmission ratio of the planetary reduction assembly is greater than or equal to 6 and less than or equal to 14. In this embodiment, the transmission ratio of the planetary reduction assembly is greater than or equal to 9 and less than or equal to 12.5, preferably, 9.5-10, and the optimal transmission ratio is 115 / 12≈9.58, and its highest output efficiency η is greater than or equal to 85%; ; Where ηout is the output efficiency, Sout is the output speed, Nout is the output torque, Uin is the input voltage, and Iin is the input current; At the same time, the 80% efficiency platform of the hub motor accounts for: ; Among them, N1 is the torque range where the motor efficiency is greater than or equal to 80%, N2 is the entire torque range of the motor, that is, the range from 0 to stall torque (maximum torque), the torque range of the 80% efficiency platform, that is, the span from the starting point to the end point of the torque range when the efficiency is greater than 80%. The larger the span, the higher the efficiency, which can enable the motor to maintain a high working efficiency under different working conditions. In this application, the efficiency above 80% accounts for more than 23%, that is, from the lowest speed (0RPM) to the highest speed, 23% and above of the output efficiency is greater than 80%.

[0024] The motor stator of the present application has excellent soft magnetic properties, low iron loss, high efficiency and energy saving. In this embodiment, the stator is made of iron-based amorphous material and is made of iron-based amorphous strip. The performance comparison between the stator and cold-rolled silicon steel is shown in the following table: Table 1:

[0025] The iron core made of amorphous materials can improve the efficiency of the motor. Amorphous materials can reduce the motor core loss by 80%-93%.

[0026] After adopting amorphous materials, the reduction mechanism needs to be redesigned so that it can match the motor body, so that the motor as a whole has the optimal output efficiency and efficiency platform.

[0027] The driving capability of the wheel hub motor should meet the following performance indicators of the vehicle: maximum speed, acceleration time, and maximum climbing grade of the vehicle.

[0028] The driving equation of the vehicle is: ; Among them, Ft is the total driving force of the vehicle, G is gravity, f is the friction between the wheel and the road, Ir is the road slope, Cd is the drag coefficient, A is the frontal area, u is the vehicle speed, is the mass conversion coefficient and m is the vehicle weight.

[0029] The driving equation of the vehicle is: ; Among them, Pw is the total output power of the hub motor, Ft is the total driving force of the vehicle, G is gravity, f is the friction between the wheel and the road, Ir is the road slope, Cd is the drag coefficient, A is the frontal area, u is the vehicle speed, is the mass conversion coefficient, m is the vehicle weight, is the transmission efficiency of the hub motor; When the vehicle is in an ideal state, that is, traveling at a constant speed at the highest speed on a road with no slope, the driving power of a single wheel hub motor is: ; Among them, Pu is the wheel hub motor driving power at the highest vehicle speed, umax is the maximum vehicle speed, G is gravity, f is the friction between the wheel and the road surface, Cd is the wind resistance coefficient, A is the windward area, is the transmission efficiency of the hub motor; When the vehicle is traveling at the maximum slope, the driving power of a single wheel hub motor is: ; Among them, Pi is the driving power of the hub motor at the maximum climbing slope, ut is the climbing speed, G is gravity, f is the friction between the wheel and the road surface, Cd is the wind resistance coefficient, A is the frontal area, is the transmission efficiency of the hub motor, Imax is the maximum slope; When the vehicle accelerates from 0 to Ut, the driving power of a single wheel hub motor is: ; Among them, Pt is the driving power required to accelerate from 0 to ut; G is gravity, f is the friction between the wheel and the road, Cd is the drag coefficient, A is the frontal area, ut is the vehicle speed, is the mass conversion coefficient, m is the vehicle weight, is the transmission efficiency of the hub motor; Therefore, the peak power Pp of the hub motor needs to meet the following conditions: ; Among them, Pu is the driving power of the hub motor at the highest vehicle speed, Pi is the driving power of the hub motor at the maximum climbing slope, and Pt is the driving power required to accelerate from 0 to ut; The maximum speed np is determined by the maximum vehicle speed umax, wheel radius Rw and the reduction ratio iq of the hub motor, and its calculation formula is: ; Among them, np is the maximum speed, umax is the maximum vehicle speed, Rw is the wheel radius, and iq is the reduction ratio; The reduction ratio is obtained as; ; The maximum torque Tp of the wheel hub is: ; Among them, Tp is the maximum torque, Pp is the peak power of the motor, and np is the maximum speed; Rated power Pm is: ; Among them, Pm is the rated power, Pp is the peak power, is the overload factor; In the present application, the wheel size of the load is 16 inches-28 inches, and the required output speed is 180RPM-420RPM, and the output linear speed of the wheel can be calculated; at the same time, according to the installation requirements of the load, the thickness of the hub shell is 80mm-120mm, and the diameter is 110mm-145mm. Therefore, the internal installation space, that is, the size of the stator and the rotor has certain limitations. According to the formula, the calculation is combined with the calculation results and the installation space to obtain a transmission ratio of 6-14 in the space, preferably 9-12 or 9-12.5. Due to the use of new materials, the efficiency platform changes. Therefore, motor samples are made and data analysis is performed on different transmission ratios. After years of research and development by our R&D personnel, it is found that when 18 / 45 and 18 / 69 are used, the best efficiency platform is achieved, that is, the number of teeth of the central gear is 18, the number of teeth of the large gear of the planetary gear is 45, the number of teeth of the small gear of the planetary gear is 18, and the number of teeth of the ring gear is 69. At this time, the transmission ratio i is ; That is, under this transmission ratio, the hub motor has the optimal efficiency platform and can meet the design requirements of the load; Our R&D personnel conducted tests, comparisons and analyses on different speeds and transmission ratios of new and old materials. The test data are as follows: Table 2: New material (amorphous) motor 1, no-load speed 198RPM, transmission ratio 9.58;

[0030]

[0031]

[0032] From the test data in Table 2 above, it can be seen that the maximum efficiency is 86.80%, the starting point of 80% efficiency torque is 2.51 (N·M), the ending point of 80% efficiency torque is 22.25 (N·M), and the efficiency platform torque range is 19.74.

[0033] Table 3: New material (amorphous) motor 2, no-load speed 233RPM, transmission ratio 9.58;

[0034] From the test data in Table 3 above, it can be seen that the maximum efficiency is 86.80%, the starting point of 80% efficiency torque is 4.6 (N·M), the ending point of 80% efficiency torque is 22.6 (N·M), and the efficiency platform torque range is 18.

[0035] Table 4: New material (amorphous) motor 3, no-load speed 356RPM, transmission ratio 9.58;

[0036]

[0037] From the test data in Table 4 above, it can be seen that the maximum efficiency is 83.60%, the starting point of 80% efficiency torque is 5.15 (N·M), the ending point of 80% efficiency torque is 16.71 (N·M), and the efficiency platform torque range is 11.56.

[0038] Table 5: Old material (silicon steel) motor 4, no-load speed 198RPM, transmission ratio 9.58;

[0039]

[0040]

[0041] From the test data in Table 5 above, it can be seen that the maximum efficiency is 80.40%, the starting point of 80% efficiency torque is 12.69 (N·M), the ending point of 80% efficiency torque is 18.27 (N·M), and the efficiency platform torque range is 5.58.

[0042] Table 6: Old material (silicon steel) motor 5, no-load speed 232RPM, transmission ratio 9.58;

[0043]

[0044] Table 6: Old material (silicon steel) motor 5, no-load speed 232RPM, transmission ratio 9.58; From the test data in Table 6 above, it can be seen that the highest efficiency is 79.6%, which is less than 80%, and there is no 80% efficiency platform.

[0045] Table 7: Old material (silicon steel) motor 6, no-load speed 366RPM, transmission ratio 9.58;

[0046]

[0047]

[0048] From the test data in Table 7 above, it can be seen that the highest efficiency is 77.40%, which is less than 80% and there is no 80% efficiency platform.

[0049] Table 8: New material (amorphous) motor 7, no-load speed 199RPM, transmission ratio 11.2;

[0050] From the test data in Table 8 above, it can be seen that the maximum efficiency is 86.80%, the starting point of 80% efficiency torque is 5.4 (N·M), the ending point of 80% efficiency torque is 26.4 (N·M), and the efficiency platform torque range is 21.

[0051] Table 9: New material (amorphous) motor 8, no-load speed 247RPM, transmission ratio 11.2;

[0052]

[0053] From the test data in Table 9 above, it can be seen that the maximum efficiency is 85.60%, the starting point of 80% efficiency torque is 4.8 (N·M), the ending point of 80% efficiency torque is 23 (N·M), and the efficiency platform torque range is 18.2.

[0054] Table 10: New material (amorphous) motor 9, no-load speed 304RPM, transmission ratio 11.2;

[0055]

[0056]

[0057] From the test data in Table 10 above, it can be seen that the maximum efficiency is 83.7%, the starting point of 80% efficiency torque is 5.5 (N·M), the ending point of 80% efficiency torque is 20 (N·M), and the efficiency platform torque range is 14.5.

[0058] Table 11: Old material (silicon steel) motor 10, no-load speed 198RPM, transmission ratio 11.2;

[0059]

[0060] It can be seen from the test data in Table 11 above that the highest efficiency is 79.60%, which does not reach 80% efficiency.

[0061] Table 12: Old material (silicon steel) motor 11, no-load speed 247RPM, transmission ratio 11.2;

[0062]

[0063]

[0064] From the test data in Table 12 above, it can be seen that the highest efficiency is 77.7%, which is less than 80%, and there is no 80% efficiency platform.

[0065] Table 13: Old material (silicon steel) motor 12, no-load speed 313RPM, transmission ratio 11.2;

[0066]

[0067] From the test data in Table 13 above, it can be seen that the maximum efficiency is 80.4%, the starting point of the 80% efficiency torque is 16.46 (N·M), the ending point of the 80% efficiency torque is 16.46 (N·M), and the efficiency platform torque range is 0.

[0068] Table 14: New material (amorphous) motor 13, no-load speed 237RPM, transmission ratio 11.2;

[0069]

[0070]

[0071] From the test data in Table 14 above, it can be seen that the maximum efficiency is 85.30%, the starting point of 80% efficiency torque is 4.93 (N·M), the ending point of 80% efficiency torque is 22 (N·M), and the efficiency platform torque range is 17.07.

[0072] Table 15: New material (amorphous) motor 14, no-load speed 233RPM, transmission ratio 9.58;

[0073]

[0074] From the test data in Table 15 above, it can be seen that the maximum efficiency is 86.80%, the starting point of 80% efficiency torque is 4.6 (N·M), the ending point of 80% efficiency torque is 22.6 (N·M), and the efficiency platform torque range is 18.

[0075] Table 16: New material (amorphous) motor 15, no-load speed 240RPM, transmission ratio 4.43;

[0076]

[0077] From the test data in Table 16 above, it can be seen that the maximum efficiency is 85.10%, the starting point of 80% efficiency torque is 1 (N·M), the ending point of 80% efficiency torque is 7 (N·M), and the efficiency platform torque range is 6.

[0078] In order to intuitively understand the efficiency platform under different materials, different speeds and different transmission ratios, the above table data is processed into curves to facilitate comparative analysis.

[0079] See Table 2, Table 5 and Figure 2 , where Table 2 is the test data of the motor with amorphous core (new motor 1), and Table 5 is the test data of the motor with silicon steel core (old motor 4). The speed of both motors is 198RPM, and the transmission ratio is 9.58. It can be seen that the starting point of the 80% efficiency torque of the new motor 1 (hereinafter referred to as the efficiency platform starting point) is 2.51N·M, the end point of the 80% efficiency torque (hereinafter referred to as the efficiency platform end point) is 22.25N·M, and the torque range of the 80% efficiency platform (hereinafter referred to as the efficiency platform range) is 19.7 4. When the torque is 7.37N·M, the efficiency reaches the highest, which is 86.80%; under the same conditions, the efficiency platform starting point of the old motor 4 is 12.69N·M, the efficiency platform end point is 18.27N·M, and the efficiency platform interval is 5.58, which is much smaller than the 19.74 of the new motor 1. When the torque is 13.4N·M, the efficiency is the highest, which is 80.40%, which is less than the highest efficiency of the new motor 1; the efficiency platform of the new motor 1 is much better than that of the old motor 4, that is, the new motor has higher efficiency and better use effect.

[0080] See Table 3, Table 6 and Figure 3, where Table 3 is the test data of the motor with an amorphous core (new motor 2), and Table 6 is the test data of the motor with a silicon steel core (old motor 5). The speed of both motors is 230RPM, and the transmission ratio is 9.58. It can be seen that the starting point of the efficiency platform of the new motor 2 is 4.6N·M, the end point of the efficiency platform is 22.6N·M, and the efficiency platform interval is 18. When the torque is 11.3N·M, the efficiency reaches the highest, which is 86.80%; under the same conditions, the maximum efficiency of the old motor 5 is 79.6%, which has not reached the starting point of 80% efficiency, that is, there is no efficiency platform. Under the same conditions, the performance of the motor using the new material is far better than that of the motor using the old material.

[0081] See Table 4, Table 7 and Figure 4 , where Table 4 is the test data of the motor with an amorphous core (new motor 3), and Table 7 is the test data of the motor with a silicon steel core (old motor 6). Both have a rotation speed of 360RPM and a transmission ratio of 9.58. It can be seen that the efficiency platform starting point of the new motor 3 is 5.15N·M, the efficiency platform end point is 16.71N·M, and the efficiency platform interval is 11.56. When the torque is 9.34N·M, the efficiency reaches the highest, which is 83.6%; under the same conditions, the maximum efficiency of the old motor 6 is 77.4%, which has not reached the starting point of 80% efficiency, that is, there is no efficiency platform. Under the same conditions, the performance of the motor using the new material is far better than that of the motor using the old material.

[0082] The above three groups of tests are comparisons between the new and old motors under the same conditions (same speed, same transmission ratio). It can be seen from the data and curves that under the same speed and the same transmission ratio, after using the new motor made of amorphous materials, the maximum efficiency end is improved by 7.9%-8.0%, and the average efficiency is improved by 8.9%-19.1%. That is, the new motor has higher working efficiency, a wider efficiency platform range, and better use effect.

[0083] See Table 8, Table 11 and Figure 5 Table 8 shows the test data of the motor with an amorphous core (new motor 7), and Table 11 shows the test data of the motor with a silicon steel core (old motor 10). The rotation speed of both motors is 200RPM, and the transmission ratio is 11.2. It can be seen that the efficiency platform starting point of the new motor 7 is 5.4N·M, the efficiency platform end point is 26.4N·M, and the efficiency platform interval is 21. When the torque is 13.2N·M, the efficiency reaches the highest, which is 86.80%. Under the same conditions, the maximum efficiency of the old motor 10 is 79.6%, which does not reach 80%, that is, there is no efficiency platform. Under the same conditions, the performance of the motor using the new material is far better than that of the motor using the old material.

[0084] See Table 9, Table 12 and Figure 6 , where Table 4 is the test data of the motor with an amorphous core (new motor 8), and Table 12 is the test data of the motor with a silicon steel core (old motor 11). Both have a rotation speed of 250RPM and a transmission ratio of 11.2. It can be seen that the efficiency platform starting point of the new motor 8 is 4.8N·M, the efficiency platform end point is 23N·M, and the efficiency platform interval is 18.2. When the torque is 12.33N·M, the efficiency reaches the highest, which is 85.6%; under the same conditions, the maximum efficiency of the old motor 11 is 77.7%, which is less than 80%, and there is no 80% efficiency platform. The efficiency platform of the new motor 8 is far better than that of the old motor 11, that is, the new motor has higher efficiency and better use effect.

[0085] See Table 10, Table 13 and Figure 7 , where Table 10 is the test data of the motor (new motor 9) using an amorphous core, and Table 13 is the test data of the motor (old motor 12) using a silicon steel core. Both have a rotation speed of 300RPM and a transmission ratio of 11.2. It can be seen that the efficiency platform starting point of the new motor 9 is 5.5N·M, the efficiency platform end point is 20N·M, and the efficiency platform interval is 14.5. When the torque is 14.19N·M, the efficiency reaches the highest efficiency of 83.70%; under the same conditions, the efficiency platform starting point of the old motor 12 is 16.46N·M, the efficiency platform end point is also 16.46N·M, and the efficiency platform interval is 0, that is, the efficiency interval is extremely small and can be ignored. The interval span is much smaller than 14.5 of the new motor 9. When the torque is 16.46N·M, the efficiency is the highest, which is 80.4%, which is less than the highest efficiency of the new motor 9; the efficiency platform of the new motor 9 is far better than that of the old motor 12, that is, the new motor has higher efficiency and better use effect.

[0086] The above three groups of tests are comparisons between the new and old motors under the same conditions (same speed, same transmission ratio). It can be seen from the data and curves that, under the same speed and the same transmission ratio, after using the new motor made of amorphous materials, the maximum efficiency end is improved by 4.1%-10.16%, and the average efficiency is improved by 15.5%-20.1%. That is, the new motor has higher working efficiency, a wider efficiency platform range, better use effect, and more obvious energy saving.

[0087] See Table 14-Table 16 and Figure 8, which are new motors 13-15, with a speed of 240RPM, and transmission ratios of 11.2, 9.58 and 4.43 respectively. It can be seen that when the transmission ratio is 11.2, the efficiency platform starting point of the new motor 13 (transmission ratio 11.2) is 4.93N·M, the efficiency platform end point is 22N·M, the efficiency platform interval is 17.07, and the average efficiency is 66.13%. When the torque is 7.91N·M, the efficiency reaches the highest, which is 85.30%; the efficiency platform starting point of the new motor 14 (transmission ratio 9.58) is 4.6N·M. ·M, the end point of the efficiency platform is 22.6N·M, the efficiency platform interval is 18, the average efficiency is 68.29%, and when the torque is 11.3N·M, the efficiency reaches the highest efficiency of 86.80%; the efficiency platform starting point of the new motor 15 (transmission ratio 4.43) is 1N·M, the end point of the efficiency platform is 7N·M, the efficiency platform interval is 6, and the average efficiency is 66.23%. When the torque is 3.38N·M, the efficiency reaches the highest efficiency of 85.1%; it can be seen that at the same speed, the transmission ratio of 9.58 has the best working efficiency.

[0088] The hub motor of the present invention has an iron core made of amorphous material, and the transmission ratio is optimized. While improving the efficiency of the motor, it also broadens the efficiency platform range, so that the motor can maintain a high working efficiency under different working conditions, which not only reduces energy consumption and brings a longer cruising range, but also improves the stability and reliability of the motor in the full range of working conditions, making the driving control of the whole vehicle smoother; at the same time, under the premise of meeting the design requirements, the volume of the product is greatly reduced, the installation space is reduced, which is conducive to the installation and layout on the vehicle, reduces the production cost, and enhances the market competitiveness. This enables the motor to show excellent performance in a variety of application scenarios and meets the urgent needs of modern transportation for high efficiency and low energy consumption; in addition, the use of amorphous materials also brings good thermal stability and corrosion resistance, the iron core loss is small, further extends the service life of the motor, reduces the maintenance cost, and brings a better experience to users; the hub motor of the present invention has a compact structure, small size, high working efficiency, and a large efficiency platform range, and good use effect.

[0089] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A hub motor, characterized in that: include: A main shaft, used for connection with the frame; A wheel hub shell, serving as an output end and used to be connected to a wheel, wherein the wheel hub shell is rotatably mounted on the main shaft; A stator, located in the hub shell and fixed on the main shaft; A rotor, located in the hub shell and capable of rotating around the stator; A planetary reduction assembly, disposed between the rotor and the wheel hub shell, for transmitting the power of the rotor to the wheel hub shell and driving the wheel hub shell to rotate; The iron core of the stator and / or the rotor is made of amorphous material; The rated speed of the hub shell is 180RPM-420RPM, and the transmission ratio of the planetary reduction assembly is greater than or equal to 6 and less than or equal to 14.

2. The hub motor according to claim 1, characterized in that: The transmission ratio of the planetary reduction assembly is greater than or equal to 9 and less than or equal to 12.

5.

3. The hub motor according to claim 1, characterized in that: The rated torque of the hub shell is 8NM-16NM.

4. The hub motor according to claim 1, characterized in that: The transmission ratio of the planetary reduction assembly is 115 / 12.

5. The hub motor according to claim 1, characterized in that: The planetary reduction assembly includes a central gear fixed to the rotor, a ring gear fixed to the inner wall of the hub shell, a planetary carrier fixed to the main shaft, and a plurality of planetary gears arranged on the planetary carrier. The planetary gears are double gears and have a large gear end meshing with the central gear and a small gear end meshing with the ring gear, thereby forming a secondary reduction.

6. The hub motor according to claim 5, characterized in that: The number of teeth of the central gear is 18, the number of teeth of the large gear end of the planetary gear is 45, the number of teeth of the small gear end is 18, and the number of teeth of the ring gear is 69.

7. The hub motor according to claim 1, characterized in that: The 80% efficiency platform of the hub motor accounts for: ； Among them, N1 is the torque range when the motor efficiency is greater than or equal to 80%, and N2 is the entire torque range of the motor.

8. The hub motor according to claim 1, characterized in that: The maximum efficiency of the hub motor is greater than or equal to 85%.

9. The hub motor according to claim 1, characterized in that: The diameter of the wheel hub shell is 110mm-145mm, and the axial width of the wheel hub shell is 80mm-120mm.

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