Cooling medium flow guide structure of vertical outer rotor wheel hub motor

Abstract

The utility model discloses a kind of cooling medium flow guide structure of vertical outer rotor wheel hub motor, including the inner stator support and outer rotor shell of axis line horizontal arrangement, the outer rotor assembly is equipped in the inner side of outer rotor shell, the outer rotor assembly includes rotor core and permanent magnet;The flow guide structure is equipped in the inner side of outer rotor shell, the flow guide structure is located between rotor core and outer rotor shell, for cooling medium is guided to the one end of outer rotor shell, and forms cooling medium recovery end.The utility model can guide cooling medium to the side of wheel hub motor, make it gather in the side of wheel hub motor, to facilitate the cooling medium in wheel hub motor to be discharged.

Description

Technical Field

[0001] This utility model relates to the field of hub electric drive system technology, and in particular to a cooling medium guiding structure for a vertical external rotor hub motor. Background Technology

[0002] With the rapid development of automotive electrification and intelligence, the application of in-wheel electric drive in the electric vehicle field is becoming increasingly prominent. In-wheel electric drives can be divided into internal rotor motors and external rotor motors based on the rotor position of the motor. Due to the high output torque and limited space of in-wheel electric drives, direct-drive in-wheel drives typically use external rotor motors. This design offers high power density, small motor size, and high output torque. However, because of the limited space in in-wheel motors, and because the main heat source (stator windings) of external rotor motors is internal, their heat dissipation is poor, making them prone to overheating and damage.

[0003] Existing technologies for heat dissipation in external rotor motors typically employ two methods:

[0004] The first design uses a closed fluid channel between the stator mounting bracket and the mounting shaft, where a cooling medium (such as water or cooling oil) flows to remove heat. However, this design suffers from limited heat exchange area at the channel location, especially in areas with high heat generation where direct contact with the cooling medium significantly reduces its heat dissipation capacity.

[0005] The second method involves enclosing the stator winding assembly entirely with a cover, creating a sealed annular space between the stator assembly's mounting shaft and the cover. The stator assembly is then placed within this annular space. Oil inlets and outlets are then added to the sealed space, allowing cooling oil to circulate and remove heat. This approach increases the air gap between the stator and rotor, significantly impacting motor efficiency and torque output, and presents considerable drawbacks.

[0006] To address the aforementioned issues, the applicant has proposed a direct spraying solution for the stator coils, which can quickly and efficiently cool the interior of the external rotor motor. However, since the external rotor is constantly rotating during operation, the cooling medium, once it enters the external rotor housing, will accumulate on the inner wall of the housing under centrifugal force and rotate with the housing, or accumulate in large quantities on both sides of the housing. This prevents the cooling medium from being collected and discharged in a timely and effective manner, thus failing to achieve its heat dissipation function. Furthermore, the accumulation of oil will increase rotational resistance and affect the motor's efficiency.

[0007] There is an urgent need to provide a solution that can effectively address the above problems. Utility Model Content

[0008] In view of the above-mentioned shortcomings of the existing technology, the purpose of this utility model is to solve the problem that the cooling medium in the external rotor hub motor cannot be discharged quickly and effectively. It provides a cooling medium guiding structure for a vertical external rotor hub motor, which can guide the cooling medium to one side of the hub motor and make it collect on one side of the hub motor, thereby facilitating the discharge of the cooling medium in the hub motor.

[0009] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: a cooling medium guiding structure for a vertical external rotor hub motor, comprising an inner stator support and an outer rotor housing arranged horizontally along the axis, wherein an outer rotor assembly is provided on the inner side of the outer rotor housing, and the outer rotor assembly includes a rotor core and a permanent magnet; characterized in that: the guiding structure is provided on the inner side of the outer rotor housing, the guiding structure is located between the rotor core and the outer rotor housing, and is used to guide the cooling medium to one end of the outer rotor housing and form a cooling medium recovery end.

[0010] Furthermore, the flow guiding structure is disposed on the inner wall of the outer rotor housing, and the maximum distance between the flow guiding structure and the axis of the outer rotor assembly gradually increases from the end of the outer rotor housing away from the recovery end to the end closer to the recovery end.

[0011] Furthermore, the flow guiding structure is a flow guiding hole, and the side of the flow guiding hole wall away from the axis of the outer rotor assembly is an inclined surface.

[0012] Furthermore, the flow guiding structure is a guide groove, and the depth of one end of the guide groove is greater than the depth of the other end, so that the bottom of the guide groove is an inclined surface.

[0013] Furthermore, the flow guiding structure employs a spiral hole or a spiral groove.

[0014] Furthermore, on the outer side of the outer rotor housing, there are reinforcing ribs corresponding to the flow guiding structure.

[0015] Furthermore, the maximum distance between the outer wall of the outer rotor housing and the axis of the outer rotor assembly gradually increases from the end of the outer rotor housing away from the recovery end to the end closer to the recovery end.

[0016] Furthermore, the rotor core is annular or the cross-section of the rotor core is U-shaped; when the rotor core is annular, the permanent magnet is located inside the rotor core; when the cross-section of the rotor core is U-shaped, the permanent magnet is located inside the two side plates of the rotor core, and the inner stator support is located inside the rotor core.

[0017] Furthermore, an annular recovery cover is provided at the recovery end of the outer rotor housing. The recovery cover is fixedly connected to the inner stator support and rotatably connected to the outer rotor housing. At least one through hole is provided at the recovery end of the outer rotor housing corresponding to the position of the recovery cover, and the through hole is connected to the recovery cover. A discharge hole is provided at the lower part of the recovery cover.

[0018] Furthermore, the outer rotor housing has an open end for recycling, and a recycling cover is provided at the open end. The recycling cover is fixedly connected to the inner stator support and rotatably connected to the outer rotor housing. A discharge hole is provided at the lower part of the recycling cover.

[0019] Compared with the prior art, the present invention has the following advantages: The structure of this solution is simple. Through the flow guiding structure, the cooling medium in the outer rotor housing can be quickly and timely guided to one end of the outer rotor housing, thereby effectively collecting the cooling medium and making the cooling medium gather at one end of the outer rotor housing. In this way, the cooling medium can be discharged by simply cooperating with an external mechanism (such as an oil suction pump). This can not only improve the cooling effect, but also avoid the accumulation of cooling medium causing an increase in rotational resistance and affecting the efficiency of the hub motor. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of this utility model.

[0021] Figure 2 This is a structural schematic diagram of Embodiment 2 of the present invention.

[0022] In the diagram: 1—Inner stator support, 2—Outer rotor housing, 3—Rotor core, 4—Permanent magnet, 5—Flow guiding structure, 6—Recovery cover. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely to represent selected embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0025] It should be noted that similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the figures, or the orientation or positional relationship commonly used when the product of this utility model is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance. In addition, the terms "horizontal," "vertical," etc., do not indicate that the component is required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0026] Example: See Figure 1 See Figure 1 A cooling medium guiding structure for a vertical external rotor hub motor includes an inner stator support 1 and an outer rotor housing 2 arranged horizontally along the axis. An outer rotor assembly is provided inside the outer rotor housing 2, and the outer rotor assembly includes a rotor core 3 and a permanent magnet 4. In this embodiment, the rotor core 3 is annular, and the permanent magnet 4 is located inside the rotor core 3; that is, the entire hub motor adopts a radial flux motor.

[0027] The flow guiding structure 5 is provided on the inner side of the outer rotor housing 2. The flow guiding structure 5 is located between the rotor core 3 and the outer rotor housing 2, and is used to guide the cooling medium (usually cooling oil) to one end of the outer rotor housing 2, forming a cooling medium recovery end. Specifically, the flow guiding structure 5 is located on the inner wall of the outer rotor housing 2. The maximum distance between the flow guiding structure 5 and the axis of the outer rotor assembly gradually increases from the end of the outer rotor housing 2 furthest from the recovery end to the end closest to the recovery end. Thus, under the action of centrifugal force, the cooling medium flows along the side wall of the flow guiding structure 5 to the recovery end. In practice, the flow guiding structure 5 is a flow guiding hole, and the side of the hole wall furthest from the axis of the outer rotor assembly is an inclined surface.

[0028] To facilitate the machining of the flow guiding structure 5, the maximum distance between the outer wall of the outer rotor housing 2 and the axis of the outer rotor assembly gradually increases from the end of the outer rotor housing 2 furthest from the recovery end to the end closest to the recovery end. This is because the outer rotor housing 2 is generally conical, giving it sufficient thickness and thus improving stability after machining. To further improve the stability of the outer rotor housing 2, reinforcing ribs are provided on the outer side of the outer rotor housing 2 corresponding to the flow guiding structure 5.

[0029] In this embodiment, an annular recovery cover 6 is coaxially arranged at the recovery end of the outer rotor housing 2. The recovery cover 6 is fixedly connected to the inner stator support 1 and rotatably connected to the outer rotor housing 2. A sealing ring is provided between the recovery cover 6 and the outer rotor housing 2 to improve the sealing effect. At least one through hole is provided at the recovery end of the outer rotor housing 2 corresponding to the position of the recovery cover 6, and the through hole connects to the recovery cover 6. Thus, after the cooling medium inside the outer rotor housing 2 collects at the recovery end, it can flow into the recovery cover 6 through the through hole and be stored inside the recovery cover 6. A discharge hole is provided at the bottom of the recovery cover 6, which facilitates the circulation of coolant with an oil pump or other assemblies, effectively improving the heat dissipation effect on the inner stator support and the outer rotor assembly.

[0030] This solution has a simple structure. The flow guiding structure 5 can quickly and timely guide the cooling medium inside the outer rotor housing 2 to one end of the outer rotor housing, thereby effectively collecting the cooling medium and converging it at one end of the outer rotor housing 2. In this way, with the help of an external mechanism (such as an oil suction pump), the cooling medium can be discharged, which can improve the cooling effect and avoid the accumulation of cooling medium causing increased rotational resistance and affecting the efficiency of the hub motor.

[0031] Example 2, see Figure 2Unlike Embodiment 1, in this embodiment, the rotor core 3 has a U-shaped cross-section, the permanent magnet 4 is located on the inner side of the two side plates of the rotor core 3, and the inner stator support is located inside the rotor core 3; that is, the entire hub motor adopts an axial flux motor. In this design, the flow guiding structure 5 is a guide groove, and the depth of one end of the guide groove is greater than the depth of the other end, making the bottom of the guide groove a slope; this makes processing more convenient, and the guide groove and the rotor core 3 cooperate to form a flow guiding hole, which can cool the rotor core 3, thereby further improving the cooling effect.

[0032] During implementation, the outer rotor housing 2 has an open end for recycling, and a recycling cover 6 is provided at the open end. The recycling cover 6 is fixedly connected to the inner stator support 1 and rotatably connected to the outer rotor housing 2. A discharge hole is provided at the lower part of the recycling cover 6. With this solution, the entire structure is more compact and assembly is more convenient.

[0033] Example 3 differs from Examples 1 and 2 in that the flow-guiding structure employs spiral holes or spiral grooves. During implementation, when the hub motor is rotating and the vehicle is moving forward, the spiral holes or spiral grooves guide the coolant into the recovery shroud, resulting in better and faster flow. However, when the hub motor is rotating and the vehicle is reversing, the vehicle speed is typically low, and with the external oil suction device present, there is virtually no reverse flow of coolant. Therefore, heat dissipation from the hub motor is not a major concern during this process.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model and not to limit the technical solutions. Those skilled in the art should understand that any modifications or equivalent substitutions to the technical solutions of this utility model that do not depart from the spirit and scope of this technical solution should be covered within the scope of the claims of this utility model.

Claims

1. A cooling medium guiding structure for a vertical external rotor hub motor, comprising an inner stator support and an outer rotor housing arranged horizontally along the axis, wherein an outer rotor assembly is provided inside the outer rotor housing, and the outer rotor assembly includes a rotor core and a permanent magnet; characterized in that: The flow guiding structure is provided on the inner side of the outer rotor housing. The flow guiding structure is located between the rotor core and the outer rotor housing and is used to guide the cooling medium to one end of the outer rotor housing and form a cooling medium recovery end.

2. The cooling medium guiding structure of the vertical external rotor hub motor according to claim 1, characterized in that: The flow guiding structure is located on the inner wall of the outer rotor housing. The maximum distance between the flow guiding structure and the axis of the outer rotor assembly gradually increases from the end of the outer rotor housing away from the recovery end to the end closer to the recovery end.

3. The cooling medium guiding structure of the vertical external rotor hub motor according to claim 2, characterized in that: The flow guiding structure is a flow guiding hole, and the side of the hole wall away from the axis of the outer rotor assembly is an inclined surface.

4. The cooling medium guiding structure of the vertical external rotor hub motor according to claim 2, characterized in that: The flow guiding structure is a guide groove, with the depth of one end of the guide groove being greater than the depth of the other end, so that the bottom of the guide groove is a slope.

5. The cooling medium guiding structure of the vertical external rotor hub motor according to claim 2, characterized in that: The flow guiding structure adopts a spiral hole or a spiral groove.

6. The cooling medium guiding structure of the vertical external rotor hub motor according to claim 2, characterized in that: On the outer side of the outer rotor housing, there are reinforcing ribs corresponding to the flow guiding structure.

7. The cooling medium guiding structure of the vertical external rotor hub motor according to claim 2, characterized in that: The maximum distance between the outer wall of the outer rotor housing and the axis of the outer rotor assembly gradually increases from the end of the outer rotor housing away from the recovery end to the end closer to the recovery end.

8. The cooling medium guiding structure of the vertical external rotor hub motor according to claim 1, characterized in that: The rotor core is either annular or has a U-shaped cross-section. When the rotor core is annular, the permanent magnet is located inside the rotor core. When the rotor core has a U-shaped cross-section, the permanent magnet is located inside the two side plates of the rotor core, and the inner stator support is located inside the rotor core.

9. The cooling medium guiding structure of the vertical external rotor hub motor according to claim 1, characterized in that: An annular recovery cover is provided at the recovery end of the outer rotor housing. The recovery cover is fixedly connected to the inner stator support and rotatably connected to the outer rotor housing. At the recovery end of the outer rotor housing, at least one through hole is provided corresponding to the position of the recovery cover, and the through hole is connected to the recovery cover. A discharge hole is provided at the bottom of the recovery cover.

10. The cooling medium guiding structure of the vertical external rotor hub motor according to claim 1, characterized in that: The outer rotor housing has an open end for recycling, and a recycling cover is provided at the open end. The recycling cover is fixedly connected to the inner stator support and rotatably connected to the outer rotor housing. A discharge hole is provided at the bottom of the recycling cover.

Images