A new type of in-wheel motor

Abstract

The present invention provides a novel hub motor, comprising: a motor body, a hub covering the motor body, the hub including a first hub body and a second hub body that cooperate with each other; and a motor shaft passing through the motor body and the hub; the motor body includes a stator assembly; the stator assembly includes a stator core, stator slots are defined in the stator core, and stator windings are wound in the stator slots; a rotor assembly; the rotor assembly includes a rotor core, rotor slots are defined in the rotor core, and rotor windings are wound in the rotor slots; it is set that the distance from the center of the rotor core to the outer surface of the rotor core is L1, the slot width of the stator slot is L2, and L2:L1 = (0.15 - 0.25):1; the rotor windings fill the rotor slots. The present invention also improves the structure of the hub body, which can be intelligently adjusted to improve the overall working efficiency of the motor.

Description

Technical Field

[0001] The present invention relates to the field of motors, and particularly to a novel hub motor. Background Art

[0002] The novel hub motor technology is also known as in-wheel motor technology. Its greatest feature is that it integrates the power device, transmission device, and braking device into the hub, greatly simplifying the mechanical part of the electric vehicle.

[0003] The novel hub motor drive system is mainly divided into two structural types according to the rotor type of the motor: the inner rotor type and the outer rotor type. Among them, the outer rotor type uses a low-speed outer rotor motor, and the maximum speed of the motor is 1000 - 1500 r / min, without a reduction device, and the rotation speed of the wheel is the same as that of the motor; while the inner rotor type uses a high-speed inner rotor motor, equipped with a reducer with a fixed transmission ratio. To obtain a higher power density, the rotation speed of the motor can be as high as 10000 r / min.

[0004] In the specific use process, the existing novel hub motor adopts the structure of a common self-flow motor. As described in the published patent CN201921139573.7 Figure 1 After the wheel assembly (only with magnets) is installed on the vehicle, the motor shaft is fixedly connected to the wheel axle, and the housing is fixedly connected to the hub. In the energized state, the housing rotates relative to the motor shaft, driving the wheel to rotate. The defect of this motor device is that since the magnet is fixed, during the rotation process, the magnetic flux cutting the magnetic induction line is constant, and the rotation speed and efficiency of the motor cannot be adjusted. Summary of the Invention

[0005] The purpose of the present invention is to provide a novel hub motor, which changes the drawback that the rotor assembly of the traditional novel hub motor only has magnetic steel, and during the working process, the parameters such as the speed of the motor cannot be intelligently adjusted; in addition, due to the structural improvement, the rotation speed increases, and the structure of the hub body is also improved. By adopting the following structure, intelligent adjustment can be performed, and the overall working efficiency of the motor can be improved.

[0006] To achieve the above purpose, the present invention provides a novel hub motor, which is characterized in that it includes: a motor body, a hub covering the motor body, the hub includes a first hub body and a second hub body that cooperate with each other, the first hub body and the second hub body form a sealed space, and the motor body is assembled in the sealed space; it also includes a motor shaft passing through the motor body and the hub;

[0007] The motor body includes a stator assembly; the stator assembly includes a stator core, a stator slot is opened in the stator core, and a stator winding is wound in the stator slot;

[0008] Rotor assembly; the rotor assembly includes a rotor core, a rotor slot is formed in the rotor core, and a rotor winding is wound in the rotor slot;

[0009] Set the distance from the center of the rotor core to the outer surface of the rotor core as L1, the slot width of the stator slot as L2, and L2:L1 = (0.15 - 0.25):1; the rotor winding fills the rotor slot. In the working state, the rotational speed of the motor body is 1000 - 4000 r / min, and its working efficiency remains above 90%.

[0010] This solution has made major improvements to the new type of in-wheel motor. Different from the existing in-wheel motor, the wheel assembly (rotor assembly) only has permanent magnets and does not wind coils, resulting in the inability to intelligently adjust parameters such as the speed of the motor; in addition, in other fields of the existing technology (excluding the new type of in-wheel motor), the rotor assembly winds coils and works in matching with the stator assembly. Restricted by the application scenario, generally the slot width of the rotor slot in the rotor assembly is relatively small, usually 1 cm. In this method, there are fewer coils, resulting in insufficient torque of the motor during operation and inability to be applied to places with high-speed requirements;

[0011] In this solution, to address the above two technical problems, first, the slot width of the rotor slot is increased. Secondly, from the basic theory of the motor, since the magnetic flux provided by the rotor core is constant, infinitely increasing the slot width of the rotor slot (indirectly increasing the winding) cannot achieve very high torque and will reach an equilibrium point; therefore, the slot width of the rotor slot in this solution is L2, and L2:L1 = (0.15 - 0.25):1, that is, the slot width not only solves the problem of fewer wound coils in the existing technology but also meets the torque requirement of the motor. Preferably, the slot width of the rotor slot is 2 cm, that is, it is doubled compared to the usual slot width. The increase in the slot width within a suitable range corresponds to an increase in the coils of the stator winding.

[0012] The rotational speed of the motor body of the present invention is 1000 - 4000 r / min, and its working efficiency remains above 90%; by using the improved rotor assembly as described above, the working efficiency can be maintained above 90% for a long time within a large rotational speed range, fundamentally solving the drawback of the inability to intelligently adjust parameters such as the speed of the motor. According to the signals collected corresponding to the rotational speed, the currents of the rotor assembly and the stator assembly are matched, and finally the working efficiency is maintained above 90%.

[0013] The above motor body is fixedly connected to the first hub body and the second hub body, generally by using fastening bolts for fixed connection.

[0014] In a preferred embodiment of the present invention, the first hub includes a first hub body, the first hub body forms a concave surface on one side, a first reinforcing plate is formed on the concave surface side, a second reinforcing plate is formed on the outer side of the first hub body, and a third reinforcing plate is arranged around the second reinforcing plate; the first reinforcing plate and the second reinforcing plate are arranged opposite to each other.

[0015] This solution uses a high-speed motor. In order to match the working efficiency of the motor and keep it above 90% in the normal working state, the motor speed will be automatically adjusted, which requires higher strength for the motor shaft and the hub body itself; specifically, since the first hub body and the second hub are symmetrically arranged, this solution will be described in detail with the first hub, and its structure has been improved. Three reinforcing plates are arranged on the entire first hub body, and the above three reinforcing plates are integrally formed on the first hub body and can generally be formed by die casting.

[0016] Two reinforcing plates are arranged on the outer side of the first hub body. This is because the first hub body is directly facing the outside. First, the third reinforcing plate is used to protect the hub body from external impacts, and then the second reinforcing plate, which is directly connected to the motor shaft, further protects the motor shaft at the connection.

[0017] In a preferred embodiment of the present invention, the through hole of the first hub body for the motor shaft to pass through is provided with at least one or more steps.

[0018] Furthermore, in this solution, the through hole is not a single through hole. Steps are provided at the through hole. In addition to increasing the strength, it can also improve the assembly efficiency of the motor shaft.

[0019] In a preferred embodiment of the present invention, the stepped structure located on the outer side of the first hub body is in interference fit with the motor shaft, and the stepped structure located on the concave surface is used for assembling the bearing.

[0020] Specifically, the above stepped structure is divided into two categories. One category is in interference fit with the motor shaft, and the other category is used for assembling the bearing. Among them, balls are arranged inside the bearing and are arranged circumferentially around the motor shaft.

[0021] In a preferred embodiment of the present invention, a bearing is provided between the motor shaft and the hub. In the working state, the stator assembly and the rotor assembly generate a matching induction rotational force, and the induction rotational force drives the hub to rotate.

[0022] Combined with the above stepped structure, the stepped structure completely wraps the bearing, improving the service life of the product.

[0023] In a preferred embodiment of the present invention, the outer edge of the rotor core and the inner edge of the hub body are fixedly connected by glue or pins.

[0024] Using colloid bonding has relatively low cost and can achieve large-scale industrial production; the colloid fills the entire installation surface.

[0025] In a preferred embodiment of the present invention, the rotor winding refers to the winding wound on the rotor core, and the winding is composed of multiple coils or coil groups. The coils use thick wires, and in a single rotor slot, the thick wires form 20 - 50 turns of coils.

[0026] Specifically, thick wires are used, and correspondingly, 20 - 50 turns of coils are formed by the thick wires in a single rotor slot to effectively improve the working efficiency of the motor. The working efficiency of a normal motor is only about 80%, and the working efficiency of the motor using this solution can be increased to more than 90%.

[0027] The thick wires use copper wires with a diameter of more than 1 mm. Since this solution needs to consider using DC signals for relevant control, the copper wires are used to conduct DC to reduce the DC resistance.

[0028] During the operation of the coil, the thicker copper wires will produce the skin effect (skin effect). When an alternating current (AC) passes through a conductor, due to the induction effect, the current distribution on the cross-section of the conductor is uneven. The closer to the surface of the conductor, the greater the current density. This phenomenon is called the "skin effect". The skin effect increases the effective resistance of the conductor. The higher the frequency, the more significant the skin effect. When a current with a very high frequency passes through a wire, it can be considered that the current only flows through a very thin layer on the surface of the wire, which is equivalent to a reduction in the cross-section of the wire and an increase in the resistance.

[0029] In a preferred embodiment of the present invention, it further includes a sensor assembly. The sensor assembly is arranged on the motor shaft and is connected to the control system of the motor.

[0030] When in use, the control system of the motor is powered on. When the motor needs to be started, the remote control system sends a start signal, and the stator assembly is powered on. At this time, the rotor assembly rotates around the motor shaft under the action of the magnetic force, and the housing rotates together under the drive of the rotor assembly, and the start of the motor is completed. During the operation of the motor, the sensor assembly monitors the data of the motor in real time. When the speed and efficiency do not match, the control system issues a command to change the current, thereby reducing the rotation speed of the rotor assembly. When the motor needs to be stopped, the remote control system sends a stop signal, and the motor gradually stops.

[0031] In a preferred embodiment of the present invention, on the stator slot, a wire winding slot opening is arranged on one side in the center direction of the rotor slot. After the rotor winding is wound, a slot wedge is assembled at the wire winding slot opening; from the transverse cross-section of the rotor slot, the length of the bottom of the rotor slot ≥ twice the length of the side part of the slot.

[0032] The general slot wedge is a component used to block the winding and prevent the winding from coming out. It is cut or customized from epoxy resin laminate. In this solution, when the slot width of the rotor slot increases, the amount of coils in the corresponding rotor slot also increases. In addition to blocking the overflow of the winding, the slot wedge can also apply a force to the coil winding, winding the coils to the maximum extent within a certain volume of the rotor slot to match the increase in the coils of the corresponding rotor winding within an appropriate range.

[0033] Among them, the slot width of the winding slot opening is 1-3 mm. If the slot width is too large, exceeding 3 mm, a wider slot wedge needs to be used during actual use. Generally, the slot wedge is made of insulating material, and the slot wedge is subjected to the greatest extrusion force at the winding slot opening and is prone to breakage.

[0034] If the slot width is too small, less than 1 mm, during the winding process, the efficiency is low, and only a few strands of wire can pass through, which does not meet the requirements of industrial production.

[0035] In this solution, the length of the bottom of the slot is the longest, forming an approximately "short and fat" structure with the side of the slot. During normal use, the outer periphery of the rotor assembly is connected to the tire mounting seat of the new hub motor, and the overall stability of this structure is relatively strong.

[0036] In a preferred embodiment of the present invention, the rotor slot is formed by two adjacent teeth. The rotor slot includes a bottom of the slot, a side of the slot extending from the bottom of the slot towards the center of the rotor core, and extension parts respectively arranged opposite to each other at the ends of the side of the slot. A winding slot opening is formed at the extension part; the side of the slot and the extension part are in an inwardly contracting shape.

[0037] The overall structure of the above is in a flat structure form, and at the same time, it matches the inwardly contracting structure, which can increase the accommodation area of the stator slot. On the basis that the overall volume of the motor does not increase, the winding amount increases by at least more than 50%.

[0038] Moreover, the inwardly contracting structure can also ensure the installation strength of the rotor slot. Especially, the extension part needs to bear the extrusion force generated by excessive winding. The contracting structure enables the force conduction to be more uniform and has a longer service life. Description of the Drawings

[0039] Figure 1 It is a schematic structural diagram of a rotor assembly of the prior art.

[0040] Figure 2 It is a three-dimensional view of the present invention.

[0041] Figure 3 It is a three-dimensional view of the present invention (the second hub is hidden).

[0042] Figure 4 It is an exploded view of the present invention (the second hub is hidden).

[0043] Figure 5 This is a cross-sectional view of the present invention.

[0044] Figure 6 This is a schematic structural view of the first hub of the present invention.

[0045] Figure 7 This is a schematic structural view of the first hub of the present invention from another perspective.

[0046] Figure 8 This is a schematic structural view of the motor body of the present invention.

[0047] Figure 9 This is a schematic structural view of the top view of the motor body of the present invention.

[0048] Figure 10 This is a schematic structural view of the rotor assembly of the present invention.

[0049] Figure 11 This is a schematic structural view of the stator assembly of the present invention.

[0050] Figure 12 This is a working schematic diagram of an existing motor.

[0051] Figure 13 This is a working schematic diagram of the present invention. Detailed implementation manners

[0052] The present invention will be described in detail below with reference to the embodiments shown in the drawings. However, it should be noted that these embodiments do not limit the present invention. Any equivalent transformation or substitution in terms of function, method, or structure made by those of ordinary skill in the art based on these embodiments shall fall within the protection scope of the present invention.

[0053] Embodiment 1:

[0054] As Figure 2 — Figure 5 shown, a new type of in-wheel motor includes: a motor body 300, a hub 400 that wraps the motor body, the hub 400 includes a first hub body 410 and a second hub body (not shown in the figure due to symmetric arrangement) that cooperate with each other, the first hub body and the second hub body form a sealed space, and the motor body 300 is assembled in the sealed space; it further includes a motor shaft 500 that penetrates the motor body and the hub;

[0055] The motor body 300 includes a stator assembly 200; the stator assembly 200 includes a stator core 210, a stator slot 220 is formed in the stator core, and a stator winding is wound in the stator slot;

[0056] Rotor assembly 100; the rotor assembly 100 includes a rotor core 110, a rotor slot 120 is formed in the rotor core, and a rotor winding is wound in the rotor slot 120;

[0057] It is set that the distance from the center of the rotor core 110 to the outer surface 130 of the rotor core 110 is L1, the slot width of the rotor slot is L2, and L2:L1=(0.15 - 0.25):1; the rotor winding fills the rotor slot 120.

[0058] This solution has made major improvements to the new hub motor. Different from the existing technology, the wheel assembly (rotor assembly) of the new hub motor only has permanent magnets and does not wind coils, resulting in the inability to intelligently adjust parameters such as the speed of the motor; in addition, in other fields of the existing technology (excluding new hub motors), the rotor assembly has adopted the method of winding coils and works in matching with the stator assembly. Restricted by the application scenario, generally the slot width of the rotor slot in the rotor assembly is small, usually 1 cm. In this method, there are fewer coils, resulting in insufficient torque of the motor during operation and unable to be applied to places with high-speed requirements;

[0059] In this solution, for the above two technical problems, firstly, the slot width of the rotor slot is increased. Secondly, from the basic theory of the motor, since the magnetic flux provided by the rotor core is certain, infinitely increasing the slot width of the rotor slot (indirectly increasing the winding) cannot achieve very high torque and will reach an equilibrium point; therefore, the slot width of the rotor slot in this solution is L2, and L2:L1=(0.15 - 0.25):1, that is, the slot width not only solves the problem of fewer wound coils in the existing technology but also solves the requirement for motor torque at the same time. Preferably, the slot width of the rotor slot is 2 cm, that is, it is doubled compared to the usual slot width. The increase in the slot width within a suitable range corresponds to an increase in the coils of the stator winding.

[0060] The rotational speed of the motor body of the present invention is 1000 - 4000 r / min, and its working efficiency remains above 90%; with the above improved rotor assembly, the working efficiency can be maintained above 90% in a large rotational speed range for a long time, fundamentally solving the drawback of being unable to intelligently adjust parameters such as the speed of the motor. According to the signals collected corresponding to the rotational speed, the currents of the rotor assembly and the stator assembly are matched, and finally the working efficiency is maintained above 90%.

[0061] The above motor body 300 is fixedly connected to the first hub body 410 and the second hub body 420, generally by using fastening bolts 600 for fixed connection.

[0062] Such as Figure 6 , Figure 7As shown, the first hub 410 includes a first hub body. The first hub body forms a concave surface on one side. A first reinforcing plate 4101 is formed on the concave surface side, and a second reinforcing plate 4102 is formed on the outer side of the first hub body. A third reinforcing plate 4103 is arranged around the second reinforcing plate; the first reinforcing plate 4102 and the second reinforcing plate 4102 are arranged oppositely.

[0063] This solution uses a high-speed motor. In order to match the working efficiency of the motor and keep it above 90% in the normal working state, the motor speed will be automatically adjusted, which requires higher strength for the motor shaft and the hub body itself. Specifically, since the first hub and the second hub (not shown in the figure) are symmetrically arranged, this solution will be described in detail with the first hub 410, and its structure has been improved. Three reinforcing plates are arranged on the entire first hub body, and the above three reinforcing plates are integrally formed on the first hub body and can generally be die-cast.

[0064] Two reinforcing plates are arranged on the outer side of the first hub body. This is because the first hub body is directly facing outwards. First, the third reinforcing plate is used to protect the hub body from external impacts, and then the second reinforcing plate, since it is directly connected to the motor shaft, further protects the motor shaft at the connection.

[0065] Specifically, at least one or more steps 700 are provided in the through hole of the first hub body through which the motor shaft 500 passes. In this solution, the through hole is not a single through hole, and steps are provided at the through hole. In addition to increasing the strength, it can also improve the assembly efficiency of the motor shaft.

[0066] Among them, the first step structure 710 located on the outer side of the first hub body is in interference fit with the motor shaft 500, and the second step structure 720 located on the concave surface is used for assembling the bearing 800.

[0067] Specifically, the above step structures are divided into two categories. One category is in interference fit with the motor shaft, and the other category is used for assembling the bearing. Among them, balls are arranged inside the bearing and are arranged circumferentially around the motor shaft.

[0068] A bearing 800 is provided between the above motor shaft 500 and the hub. In the working state, the stator assembly and the rotor assembly generate a matching induction rotational force, and the induction rotational force drives the hub to rotate. Combining the above step structure, the step structure completely wraps the bearing, improving the service life of the product.

[0069] The outer edge of the rotor core 110 and the inner edge of the hub body are fixedly connected by colloid or pins. Using colloid bonding has lower cost first and can be mass-produced industrially on a large scale; the colloid fills the entire installation surface.

[0070] Embodiment 2:

[0071] In addition to the solution described in Embodiment 1, this solution is specifically described in detail for the rotor assembly.

[0072] As Figures 8 - 10 shown, the rotor winding refers to the winding wound on the rotor core. The winding is composed of multiple coils or coil groups. The coils are made of thick wires, and 20 - 50 turns of coils are formed by the thin wires in a single rotor slot 120.

[0073] Specifically, thick wires are used, and 20 - 50 turns of coils are formed by the thick wires corresponding to and matching a single rotor slot, so as to effectively improve the working efficiency of the motor. The working efficiency of a normal motor is only about 80%, and the working efficiency of the motor using this solution can be increased to more than 90%.

[0074] The thick wires are made of copper wires with a diameter of more than 1 mm. Since this solution needs to consider using DC signals for related control, the copper wires are used to conduct DC to reduce the DC resistance.

[0075] During the operation of the coil, the thicker copper wires will produce the skin effect (skin effect). When an alternating current (AC) passes through a conductor, due to the induction effect, the current distribution on the cross-section of the conductor is uneven. The closer to the surface of the conductor, the greater the current density. This phenomenon is called the "skin effect". The skin effect increases the effective resistance of the conductor. The higher the frequency, the more significant the skin effect. When a current with a very high frequency passes through a wire, it can be considered that the current only flows through a very thin layer on the surface of the wire, which is equivalent to a reduction in the cross-section of the wire and an increase in the resistance.

[0076] It also includes a sensor assembly. The sensor assembly is arranged on the motor shaft and is connected to the control system of the motor. When in use, the control system of the motor is powered on. When the motor needs to be started, the remote control system sends a start signal, and the stator assembly is powered on. At this time, the rotor assembly rotates around the motor shaft under the action of the magnetic force, and the machine shell rotates together under the drive of the rotor assembly, and the start of the motor is completed. During the operation of the motor, the sensor assembly monitors the data of the motor in real time. When the speed and efficiency do not match, the control system issues an order to change the current, thereby reducing the rotation speed of the rotor assembly. When the motor needs to be stopped, the remote control system sends a stop signal, and the motor gradually stops.

[0077] Furthermore, on the rotor slot 120, a wire winding slot opening 140 is arranged on one side surface in the direction of the center of the stator slot. After the rotor winding is wound, a slot wedge is assembled at the wire winding slot opening.

[0078] The general slot wedge is a component used to block the winding and prevent the winding from running out. It is cut or customized from an epoxy resin laminate. In this solution, when the slot width of the rotor slot increases, the amount of coils in the corresponding rotor slot also increases. In addition to blocking the overflow of the winding, the slot wedge can also apply a force to the coil winding, winding the coils to the maximum extent within a certain volume of the rotor slot to match the increase in the coils of the corresponding stator winding within an appropriate range.

[0079] Among them, the slot width of the winding slot opening 140 is 1 - 3 mm. If the slot width is too large, exceeding 3 mm, a relatively wide slot wedge needs to be used during actual use. Generally, the slot wedge is made of insulating material, and the slot wedge is subjected to the maximum extrusion force at the winding slot opening and is easily broken. If the slot width is too small, less than 1 mm, the winding efficiency is low during the winding process, and only a few strands of wire can pass through, which does not meet the requirements of industrial production.

[0080] Specifically, the rotor slot 120 is formed by two adjacent teeth 150. The rotor slot 120 includes a slot bottom 1201, a slot side 1202 extending from the slot bottom 1201 towards the center of the stator core, and extension parts 1203 respectively arranged facing each other at the ends of the slot side. The winding slot opening 140 is formed at the extension part; the slot side 1202 and the extension part 1203 are in an inwardly contracting shape. The overall structure is in a flat shape, and at the same time, it matches the inwardly contracting structure, which can increase the accommodation area of the rotor slot. Without increasing the volume of the overall motor, the winding amount can be increased by at least more than 50%; and the inwardly contracting structure can also ensure the installation strength of the rotor slot. Especially, the extension part needs to bear the extrusion force generated by excessive winding, and the contracting structure enables the force to be transmitted more evenly and has a longer service life.

[0081] From the transverse cross-section of the rotor slot 120, the length of the slot bottom 1201 ≥ twice the length of the slot side 1202. In this solution, the length of the slot bottom is the longest, forming an approximate "short and fat" structure with the slot side. During normal use, the outer periphery of the rotor assembly is connected to the tire mounting seat of the new hub motor, and the overall structure has strong stability.

[0082] Example 3:

[0083] In addition to the rotor assembly described in Example 2, this solution specifically describes the structure of the stator slots of the stator assembly in detail.

[0084] As Figure 8, as shown in FIGS. 9 and 11, the stator slot 220 includes a rotor slot bottom 2201, a stator slot side portion 2202 formed by extending from the rotor slot bottom 2201 in a direction away from the center of the stator core, and stator extension portions 2203 disposed opposite to each other at the ends of the stator slot side portion 2202, and a stator winding slot opening 1204 is formed at the stator extension portion; the rotor winding slot opening of the stator slot is disposed adjacent to the winding slot of the rotor slot.

[0085] In this solution, the structure of the stator slot is somewhat similar to that of the rotor slot. The stator slot forms a "tall and thin" structure. However, the overall logic and setting method of the stator slot and the rotor slot structures are completely different. The entire winding slot openings are disposed opposite to each other. The rotor winding winds the coil from the outside to the inside, and the stator winding winds the coil from the inside to the outside; and the length of the connection line of the extension portions of the stator slot is greater than the length of the slot bottom of the stator slot. This design ensures that in the connection area between the stator assembly and the rotor assembly, there are more windings, which can make the most of the magnetic flux and improve the working efficiency of the motor; in addition, the design of the stator slot in this solution also increases the number of winding turns of the stator winding, and the coil capacity in a single stator slot is relatively large.

[0086] Embodiment 4:

[0087] As Figure 12 described, as Figure 13 described, it is a comparison diagram of the working efficiency of an existing motor and the motor of the present invention under the same working conditions.

[0088] It can be seen from the figure that the existing motor can only maintain a working efficiency of 90% in a relatively small range, while the motor adopting this solution can maintain a working efficiency of around 90% in a relatively large range (time), and can also match the torque (torsion) in the matching state at this working efficiency, with better user experience and higher efficiency.

[0089] The series of detailed descriptions listed above are only specific descriptions of the feasible implementation manners of the present invention, and they are not intended to limit the protection scope of the present invention. Any equivalent implementation manners or changes made without departing from the technical spirit of the present invention should be included in the protection scope of the present invention.

[0090] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0091] In addition, it should be understood that although this specification is described in terms of embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A hub motor, characterized in that, Comprising: A motor body, a hub covering the motor body, the hub including a first hub body and a second hub body that cooperate with each other, the first hub body and the second hub body forming a sealed space, and the motor body being assembled within the sealed space; further including a motor shaft passing through the motor body and the hub; The motor body includes a stator assembly; the stator assembly includes a stator core, stator slots being defined within the stator core, and a stator winding being wound within the stator slots; A rotor assembly; the rotor assembly includes a rotor core, rotor slots being defined within the rotor core, and a rotor winding being wound within the rotor slots; Let the distance from the center of the rotor core to the outer surface of the rotor core be L1, and the width of the stator slot be L2, where L2:L1 = (0.15 - 0.25):1; the rotor winding fills the rotor slots; in the working state, the rotational speed of the motor body is 1000 - 4000 r / min, and its working efficiency remains above 90%.

2. The hub motor according to claim 1, wherein The first hub includes a first hub body, the first hub body forming an inner concave surface on one side, a first reinforcing plate being formed on the inner concave surface side, a second reinforcing plate being formed on the outer side of the first hub body, and a third reinforcing plate being disposed around the second reinforcing plate; the first reinforcing plate and the second reinforcing plate are disposed opposite to each other.

3. A hub motor according to claim 2, characterized in that, The through-hole of the first hub body through which the motor shaft passes is provided with at least one or more steps.

4. A hub motor according to claim 3, wherein, The stepped structure located on the outer side of the first hub body is in interference fit with the motor shaft, and the stepped structure located on the inner concave surface is used for assembling a bearing.

5. A hub motor according to claim 4, characterized in that, A bearing is provided between the motor shaft and the hub, and in the working state, the stator assembly and the rotor assembly generate a matching induced rotational force, and the induced rotational force drives the hub to rotate.

6. A hub motor according to claim 1, characterized in that, The outer edge of the rotor core and the inner edge of the hub body are fixedly connected by a colloid or a pin.

7. A hub motor according to claim 1, wherein The rotor winding refers to the winding wound on the rotor core, the winding being composed of a plurality of coil groups, the coil being made of thick wire, the thick wire being made of copper wire with a diameter of more than 1 mm, and in a single rotor slot, the thick wire forms 20 - 50 turns of coils.

8. A hub motor according to claim 7, characterized in that, It further includes a sensor assembly, the sensor assembly being disposed on the motor shaft, and the sensor assembly being connected to the control system of the motor.

9. A hub motor according to claim 7, characterized in that, On the stator slot, a wire-winding slot opening is provided on one side in the center direction of the rotor slot. After the rotor winding is wound, a slot wedge is assembled at the wire-winding slot opening; from the transverse cross-section of the rotor slot, the length of the bottom of the rotor slot ≥ twice the length of the side part of the slot.

10. A hub motor according to claim 1, characterized in that, The rotor slot is formed by two adjacent teeth, the rotor slot including a bottom of the slot, a side part of the slot extending from the bottom of the slot towards the center of the rotor core, and extension parts respectively extending towards each other from the ends of the side part of the slot, a wire-winding slot opening being formed at the extension parts; the side part of the slot and the extension parts are in an inwardly contracting shape.

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