Outer rotor motor and aviation driving system with same

Abstract

The invention provides an external rotor motor and an aviation driving system with the same. The external rotor motor comprises a stator main body and a sleeve. An oil inlet and an oil outlet are formed in the stator main body, the stator main body is provided with a plurality of stator grooves extending along a first direction, in-groove windings are wound in the stator grooves, and axial cooling channels are formed among the in-groove windings of the same stator groove; the sleeve is located outside the stator body. The oil inlet is communicated with the first end, in the first direction, of the axial cooling channel, and the oil outlet is communicated with the second end, in the first direction, of the axial cooling channel. According to the invention, the technical problems of low cooling efficiency and poor sealing performance of the cooling system in the operation process of the external rotor motor in the prior art are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to an outer rotor motor and an aviation drive system having the same. Background Art

[0002] Aviation drive systems refer to drive systems used in the aviation field. They are usually composed of an outer rotor motor and a reducer, and are suitable for various high-power, high-speed UAV application scenarios. Traditional drive systems mainly use water cooling to cool the motor, thereby achieving efficient heat dissipation of the motor. However, water cooling is highly dependent on coolant, and problems such as coolant leakage or corrosion will seriously affect the cooling efficiency, thereby affecting the operating efficiency and reliability of the drive system.

[0003] In the prior art, such as the patent US20190006914A1 ELECTRIC DRIVE UNTI COOLING SYSTEMSAND METHODS, in this invention: the stator copper wire is mainly cooled by spraying at both ends, and the spraying point is the outer diameter of the copper wire.

[0004] It has the following disadvantages:

[0005] 1) The copper wire adopts the spray cooling solution, the contact area between the oil and the copper wire is limited, and the cooling effect is poor;

[0006] 2) The heat transfer path for cooling the copper wire in the slot is: copper wire → iron core → oil. Compared with copper wire → oil, there is an extra layer of thermal resistance generated by the iron core, and the cooling effect is poor;

[0007] 3) The cooling part is mainly in the outer diameter part, and the cooling effect of the inner diameter copper wire is poor. It is necessary to combine the rotor with oil to reduce the temperature of the inner copper wire.

[0008] Patent US2022 / 0200383A1 ELECTRIC MOTOR FOR AIRCRAFT PROPULSION, the overall oil circuit and sealing system are complex, and there is a risk of insulation abnormality.

[0009] Currently, external rotor motors mainly use air cooling and water cooling solutions, and the oil cooling solution lacks an effective sealing solution.

[0010] There is currently no effective solution to the above problems. Summary of the invention

[0011] The main purpose of the present invention is to provide an outer rotor motor and an aviation drive system having the same, so as to solve the technical problems of low cooling efficiency and poor sealing of the cooling system of the outer rotor motor during operation in the prior art.

[0012] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, an outer rotor motor is provided, comprising: a stator body, on which an oil inlet and an oil outlet are arranged, the stator body having a plurality of stator slots extending along a first direction, in-slot windings are wound in the stator slots, and an axial cooling channel is formed between two in-slot windings located in the same stator slot; and a sleeve, the sleeve being located on the outer side of the stator body; wherein the oil inlet is connected to a first end of the axial cooling channel, and the oil outlet is connected to a second end of the axial cooling channel.

[0013] Further, the end of the axial cooling channel away from the output shaft of the outer rotor motor along the first direction forms a first end of the axial cooling channel, and the end of the axial cooling channel close to the output shaft of the outer rotor motor along the first direction forms a second end of the axial cooling channel.

[0014] Furthermore, the end of the winding in the slot away from the output shaft along the first direction is the first winding end, and the end of the winding in the slot close to the output shaft along the first direction is the second winding end, wherein a first end cooling loop is formed between the first winding end, the stator body and the sleeve, and a second end cooling loop is formed between the second winding end, the stator body and the sleeve, the first end cooling loop is connected to the first end and the oil inlet of the axial cooling channel, and the second end cooling loop is connected to the second end and the oil outlet of the axial cooling channel.

[0015] Furthermore, the oil inlet and the oil outlet are symmetrically arranged about the central axis of the outer rotor motor along the first projection direction.

[0016] Furthermore, the first direction is the axial direction of the stator body.

[0017] Furthermore, there are multiple oil inlets, which are spaced apart along the circumferential direction of the stator body; there are multiple oil outlets, which are spaced apart along the circumferential direction of the stator body; the oil inlets and the oil outlets are arranged in pairs, and each oil inlet and the corresponding oil outlet are symmetrically arranged about the central axis of the outer rotor motor.

[0018] Furthermore, at least one of the first area of ​​the sleeve opposite to the first winding end and the second area of ​​the sleeve opposite to the second winding end is a multi-layer structure, the multi-layer structure includes a carbon fiber bearing layer and a first glass fiber insulation layer located inside the carbon fiber bearing layer, and a second glass fiber insulation layer is also arranged on the first glass fiber insulation layer away from the carbon fiber bearing layer.

[0019] Furthermore, the portion of the sleeve located between the first region and the second region includes a double-layer structure, and the double-layer structure includes a carbon fiber bearing layer and a first glass fiber insulation layer located inside the carbon fiber bearing layer.

[0020] Furthermore, the sleeve and the stator body adopt a transition fit or an interference fit.

[0021] According to another aspect of the present invention, an aviation drive system is provided, comprising an outer rotor motor, wherein the outer rotor motor is the outer rotor motor of any one of the above embodiments.

[0022] The technical solution of the present invention is applied, by building multiple stator slots into the stator body, forming an axial cooling channel between the windings in the slots, and connecting the two ends to the oil inlet and the oil outlet respectively for the introduction and export of the coolant. The coolant is directly introduced into the axial cooling channel between the windings, thereby achieving direct contact between the coolant and the windings, greatly increasing the heat exchange area, and thus improving the cooling efficiency. The external sleeve further ensures the sealing of the system and prevents coolant leakage. This solution greatly improves the cooling efficiency and simplifies the cooling path, while enhancing the reliability and safety of the motor, reducing the system complexity and the risk of coolant leakage, and providing strong support for the optimization of motor performance. The present application solves the technical problems of low cooling efficiency and poor sealing of the cooling system of the outer rotor motor during operation in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0024] Figure 1 A schematic structural diagram of a first embodiment of an outer rotor motor according to the present invention is shown;

[0025] Figure 2 A schematic structural diagram of a second embodiment of an outer rotor motor according to the present invention is shown;

[0026] Figure 3 A schematic structural diagram of an embodiment of a sleeve according to the present invention is shown;

[0027] Figure 4 A schematic structural diagram of an embodiment of a second region of a sleeve according to the present invention is shown;

[0028] Figure 5 A schematic structural diagram of an embodiment of a portion between a first region and a second region of a sleeve according to the present invention is shown;

[0029] Figure 6 A schematic diagram showing the structure of an embodiment of the first region of the sleeve according to the present invention

[0030] Figure 7 A schematic structural diagram of a third embodiment of an outer rotor motor according to the present invention is shown;

[0031] Figure 8 A schematic structural diagram of a fourth embodiment of an outer rotor motor according to the present invention is shown.

[0032] The above drawings include the following reference numerals:

[0033] 101. stator body; 102. sleeve; 103. sealing ring;

[0034] 104. Sealing bonding surface; 105. Oil inlet;

[0035] 106. A first end cooling loop; 107. A first winding end;

[0036] 108. Axial cooling channel; 109. In-slot winding;

[0037] 110. Second end cooling loop; 111. Second winding end; 112. Oil outlet;

[0038] 200, carbon fiber bearing layer; 201, first glass fiber insulation layer; 202, second glass fiber insulation layer;

[0039] 203, upper flange; 204, lower flange;

[0040] 001. Bolt; 002. Rivet. DETAILED DESCRIPTION

[0041] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0042] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0043] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0044] Now, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments may be implemented in a variety of different forms and should not be construed as being limited to the embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of the present application thorough and complete, and to fully convey the concepts of these exemplary embodiments to those of ordinary skill in the art. In the accompanying drawings, for the sake of clarity, the thickness of the layers and regions may be enlarged, and the same reference numerals are used to represent the same devices, and thus their descriptions will be omitted.

[0045] Combination Figures 1 to 8 As shown, according to a specific embodiment of the present application, an outer rotor motor and an aviation drive system having the same are provided.

[0046] Specifically, the outer rotor motor comprises: a stator body 101 and a sleeve 102. The stator body 101 is provided with an oil inlet 105 and an oil outlet 112, the stator body 101 has a plurality of stator slots extending along a first direction, the stator slots are wound with slot windings 109, and an axial cooling channel 108 is formed between two slot windings 109 located in the same stator slot; the sleeve 102 is located outside the stator body 101; wherein the oil inlet 105 is communicated with a first end of the axial cooling channel 108, and the oil outlet 112 is communicated with a second end of the axial cooling channel 108.

[0047] By applying the technical solution of the present invention, a plurality of stator slots are built into the stator body 101, and an axial cooling channel 108 is formed between the windings 109 in the slots. The two ends are respectively connected to the oil inlet 105 and the oil outlet 112 for introducing and exporting the coolant. The coolant is directly introduced into the axial cooling channel 108 between the windings, thereby achieving direct contact between the coolant and the windings, greatly increasing the heat exchange area, and thus improving the cooling efficiency. The outer sleeve 102 further ensures the sealing of the system and prevents coolant leakage. This solution greatly improves the cooling efficiency and simplifies the cooling path, while enhancing the reliability and safety of the motor, reducing the system complexity and the risk of coolant leakage, and providing strong support for the optimization of motor performance. The present application solves the technical problems of low cooling efficiency and poor sealing of the cooling system of the outer rotor motor during operation in the prior art.

[0048] Specifically, the end of the axial cooling channel 108 away from the output shaft of the outer rotor motor along the first direction forms a first end of the axial cooling channel 108 , and the end of the axial cooling channel 108 close to the output shaft of the outer rotor motor along the first direction forms a second end of the axial cooling channel 108 .

[0049] Optionally, the axial cooling channel 108 is located between the windings 109 in the same stator slot and extends along the first direction. The first end of the channel, i.e., the end away from the motor output shaft, is connected to the oil inlet 105 on the stator body 101; the second end of the channel, i.e., the end close to the motor output shaft, is connected to the oil outlet 112 on the stator body 101. Such a design ensures that the coolant can enter from one end of the motor, flow through the channel between the windings, cool the windings 109 in the slot, and then be discharged from the other end of the motor, forming a complete cooling cycle.

[0050] Specifically, the end of the output shaft of the outer rotor motor is usually the area where the windings 109 in the slots are dense and the current passes most frequently, and therefore it is also the place where the heat source is most concentrated. Using the second end of the axial cooling channel 108 (close to the end of the output shaft) as the coolant outlet means that the coolant is discharged from the location where the heat source is most concentrated after flowing through the entire winding area, ensuring that the coolant flow path covers all key heating areas. The coolant enters the motor from the first end away from the end of the output shaft, gradually flows through the winding-dense area, and finally flows out from the second end where the heat source is most concentrated. Such a flow path design allows the coolant to absorb heat evenly when flowing through the motor, avoiding overheating of the coolant when entering the motor, thereby ensuring the uniformity and efficiency of heat exchange during the entire cooling process.

[0051] It should be further explained that the axial cooling channel 108 can be configured to be corrugated. This shape can increase the contact area between the cooling medium and the winding, improve the heat exchange efficiency, and the corrugated structure also helps to guide the flow of the cooling medium, reduce flow resistance, and accelerate heat dissipation.

[0052] Furthermore, if Figure 2As shown, the end of the winding 109 in the slot away from the output shaft along the first direction is the first winding end 107, and the end of the winding 109 in the slot close to the output shaft along the first direction is the second winding end 111, wherein a first end cooling loop 106 is formed between the first winding end 107, the stator body 101 and the sleeve 102, and a second end cooling loop 110 is formed between the second winding end 111, the stator body 101 and the sleeve 102, the first end cooling loop 106 is connected to the first end of the axial cooling channel 108 and the oil inlet 105, and the second end cooling loop 110 is connected to the second end of the axial cooling channel 108 and the oil outlet 112. This design ensures that the coolant starts from the end of the outer rotor motor away from the output shaft, first cools the first winding end 107, then cools the winding dense area through the axial cooling channel 108, and finally cools the second winding end 111 at the end close to the output shaft, so that the flow path of the coolant covers the entire heating area of ​​the outer rotor motor, improving the cooling effect and thermal management performance. At the same time, this connection design also takes into account the flow resistance and emptying of the coolant, optimizes the cooling cycle, reduces the impact of local residual air on heat dissipation, and further improves the efficiency and reliability of the cooling system.

[0053] Specifically, the stator body 101 is the main structural component of the outer rotor motor, which surrounds the winding 109 in the slot and provides fixation and support. In the formation of the first end cooling loop 106, a specific part of the stator body 101 (usually near the end) together with the first winding end 107 and the sleeve 102 constitute a closed annular space. The coolant enters the outer rotor motor through the oil inlet 105 on the stator body 101, and then flows into the annular space formed between the first winding end 107 and the stator body 101, that is, the first end cooling loop 106. The sealing of the first end cooling loop 106 is achieved by the close fit between the sleeve 102 and the stator body 101.

[0054] Specifically, the second winding end 111 is located at the end of the outer rotor motor close to the output shaft, and a specific part of the stator body 101, the second winding end 111 and the sleeve 102 together form a closed annular space, namely, the second end cooling loop 110. The coolant flows out from the second end (the end close to the output shaft) of the axial cooling channel 108, directly enters the second end cooling loop 110, flows through the second winding end 111, and takes away the heat. The sleeve 102 cooperates with the stator body 101, through radial sealing and end face sealing, to form a sealing structure of the second end cooling loop 110, which ensures the efficient flow of the coolant and the reliability of the system, and avoids the leakage of the coolant under high pressure.

[0055] Specifically, the oil inlet 105 is located at the end of the outer rotor motor away from the output shaft, which is the entrance for the coolant to enter the outer rotor motor. After the coolant enters from the oil inlet 105, it directly enters the first end cooling loop 106 formed by the first winding end 107 of the winding 109 in the slot, the stator body 101 and the sleeve 102. The first end cooling loop 106 surrounds the first winding end 107, so that the coolant can directly contact and cool the first winding end 107, thereby taking away the heat generated in the initial operation of the outer rotor motor. After passing through the first end cooling loop 106, the coolant continues to pass through the axial cooling channel 108 along the axial direction of the outer rotor motor. The number of axial cooling channels 108 is consistent with that of the winding 109 in the slot, ensuring that the coolant can be evenly distributed, closely contact the winding, and improve the heat exchange efficiency. The first end of the axial cooling channel 108 is connected to the first end cooling loop 106, and the second end of the axial cooling channel 108 is connected to the second end cooling loop 110, thereby forming an axial flow path of the coolant, ensuring that the coolant can flow from one end to the other end of the outer rotor motor, and fully cooling the main heat-generating components inside the outer rotor motor. After the coolant flows through the axial cooling channel 108 and absorbs heat, it enters the second end cooling loop 110 formed by the second winding end 111 of the slot winding 109, the stator body 101 and the sleeve 102. The second end cooling loop 110 surrounds the second winding end 111, so that the coolant can continue to contact and cool the second winding end 111. Finally, the coolant is discharged from the outer rotor motor through the oil outlet 112 and returned to the cooling system for recycling.

[0056] Specifically, if Figure 1 As shown, the oil inlet 105 and the oil outlet 112 are symmetrically arranged 180 degrees about the central axis of the outer rotor motor along the first direction. This symmetrical design can ensure uniform distribution of the coolant inside the motor, avoid local overheating, and improve the running stability and reliability of the motor.

[0057] The symmetrical arrangement of the oil inlet 105 and the oil outlet 112 helps to balance the pressure distribution of the coolant inside the motor, and avoids the fluid biased to one side due to the single-sided inlet and outlet, which leads to uneven cooling. After the coolant enters the motor, it is evenly distributed in the axial direction and then flows out evenly on the other side. This symmetrical arrangement can ensure that the coolant flows evenly in the axial and radial directions of the motor, thereby achieving comprehensive cooling of the windings and other heat sources of the motor. The symmetrical arrangement of the oil inlet 105 and the oil outlet 112 helps to reduce the radial unbalanced force of the motor and avoid the flow of coolant affecting the dynamic balance of the motor, thereby improving the stability and operating performance of the motor.

[0058] Specifically, the first direction is the axial direction of the stator body 101. The first direction is defined as the axial direction of the stator body 101 based on the actual distribution of heat sources inside the motor and the optimization requirements of the coolant flow path and efficiency. Such a setting ensures that the coolant can contact all the heat-generating parts of the motor along the most direct path, improving the cooling effect, while avoiding local hot spots and reducing the flow resistance of the coolant, which is crucial to improving the thermal management performance of the motor.

[0059] Specifically, there are multiple oil inlets 105, which are spaced apart along the circumferential direction of the stator body 101; there are multiple oil outlets 112, which are spaced apart along the circumferential direction of the stator body 101; the oil inlets 105 and the oil outlets 112 are arranged in pairs, and each oil inlet 105 and the corresponding oil outlet 112 are symmetrically arranged 180 degrees about the central axis of the outer rotor motor.

[0060] Specifically, by evenly distributing the oil inlet 105 and the oil outlet 112 in the circumferential direction, the fluid dynamics inside the motor can be optimized to prevent the coolant from gathering or generating eddies at a certain position, which would result in a decrease in the cooling effect. The evenly distributed inlet and outlet design allows the coolant to flow more smoothly and evenly inside the motor, thereby improving the flow efficiency and heat exchange performance of the coolant.

[0061] Optionally, when the motor is running, the winding 109 in the slot and the iron core and other components will generate heat evenly, but if there is only one oil inlet 105 and one oil outlet 112, the distribution of the coolant inside the motor may be uneven, resulting in poor cooling effect in some areas. By increasing the oil inlet 105 and the oil outlet 112 and distributing them in the circumferential direction, the coolant can enter and flow out evenly from multiple positions of the motor, thereby improving the distribution of the coolant inside the motor and improving the balance of the cooling effect.

[0062] Specifically, the added oil inlet 105 and oil outlet 112 can make the coolant cover the heating area of ​​the motor more quickly and directly, reducing the path length of the coolant from the oil inlet 105 to the winding 109 in the slot and from the winding 109 in the slot to the oil outlet 112, thereby improving the heat exchange efficiency. In addition, the design of multiple oil inlets and oil outlets can increase the flow rate of the coolant, further accelerate the dissipation of heat, and thus improve the overall efficiency of the cooling system.

[0063] Optionally, the design of multiple oil inlets 105 and oil outlets 112 also provides a certain system redundancy. Even if a certain inlet or outlet fails, the remaining inlets or outlets can still ensure the normal flow of coolant, maintain the cooling effect of the motor, and improve the reliability of the cooling system and the operating stability of the motor.

[0064] Furthermore, if Figures 3 to 6 As shown, at least one of the first area of ​​the sleeve 102 opposite to the first winding end 107 and the second area of ​​the sleeve 102 opposite to the second winding end 111 is a multi-layer structure, and the multi-layer structure includes a carbon fiber bearing layer 200 and a first glass fiber insulation layer 201 located on the inner side of the carbon fiber bearing layer 200, and a second glass fiber insulation layer 202 is also arranged on the first glass fiber insulation layer 201 away from the carbon fiber bearing layer 200.

[0065] Specifically, the multilayer structure specifically includes a second glass fiber insulation layer 202, a first glass fiber insulation layer 201, and a carbon fiber bearing layer 200 from the inside to the outside. The insulation performance of the motor is an important guarantee for its normal operation and safety. The winding is in direct contact with the coolant, so the innermost layer should give priority to insulating materials to prevent direct electrical contact between the coolant (especially the conductive liquid) and the winding to avoid motor short circuit. The second glass fiber insulation layer 202 and the first glass fiber insulation layer 201 have good insulation performance, which can effectively isolate the winding from the coolant and ensure the electrical safety of the motor. The second glass fiber insulation layer 202 and the first glass fiber insulation layer 201 are made of low-weight glass fiber woven cloth with a thickness of 0.1mm. The second glass fiber insulation layer 202 and the first glass fiber insulation layer 201 are fitted to reduce the influence of woven pores on insulation. The carbon fiber bearing layer 200 is located on the outside of the multilayer structure, which can give full play to the high strength, high stiffness and low weight characteristics of carbon fiber materials. This arrangement can effectively resist the high pressure generated under oil cooling conditions, while reducing deformation caused by vibration and mechanical stress during motor operation, ensuring the stability and long-term reliability of the entire sleeve structure. Placing the carbon fiber bearing layer 200 on the outer layer also facilitates the inspection of its sealing and structural integrity during maintenance. If the carbon fiber layer is found to be worn or damaged, it can be replaced or repaired relatively easily without affecting the integrity of the inner insulating material and the insulation performance of the motor.

[0066] Optionally, during the operation of the motor, there is a risk of leakage between the winding 109 in the slot and the carbon fiber bearing layer 200, especially in the contact area between the first winding end 107, the second winding end 111 and the sealing sleeve 102, that is, the first area and the second area, which are locations with a higher risk of leakage. This area is paved with the second glass fiber insulation layer 202 and the first glass fiber insulation layer 201. Paving can significantly increase the insulation thickness and strength between the end winding and the carbon fiber bearing layer, enhance the sealing effect and structural rigidity, and reduce the leakage of coolant. After paving is completed, curing treatment is required to ensure the structural stability and insulation performance of the material. The curing process can adopt methods such as autoclave, RTM (resin transfer molding) or molding, depending on the size, shape and manufacturing conditions of the motor.

[0067] Specifically, the portion of the sleeve 102 located between the first region and the second region includes a double-layer structure, and the double-layer structure includes a carbon fiber bearing layer 200 and a first glass fiber insulation layer 201 located inside the carbon fiber bearing layer 200 .

[0068] The winding end area is in direct contact with the coolant and has a higher voltage potential, so it is an area with a higher risk of leakage in the motor. Therefore, it is necessary to form a thicker and tougher insulation layer by adding a second glass fiber insulation layer 202 to ensure that no electrical short circuit occurs between the motor winding and the carbon fiber bearing layer under high-pressure oil cooling conditions. In the non-winding end area, the sleeve 102 adopts a double-layer structure, namely a carbon fiber bearing layer 200 and a first glass fiber insulation layer 201. In the non-winding end area, the insulation risk is lower, so a double-layer structure is adopted, and only the necessary first glass fiber insulation layer 201 is retained to maintain good mechanical properties while reducing unnecessary weight increase to achieve a lightweight design.

[0069] The multi-layer insulation structure may affect the heat conduction efficiency because the thermal conductivity of glass fiber is not as good as that of carbon fiber. Due to the insulation requirements of the winding end area, it is necessary to sacrifice some heat conduction efficiency, but in the non-winding end area, only the double-layer structure of the carbon fiber bearing layer 200 and the first glass fiber insulation layer 201 is retained to ensure better heat conduction, thereby improving the cooling efficiency.

[0070] The introduction of multi-layer structure increases manufacturing cost and process complexity. Using double-layer structure in areas with lower insulation requirements can simplify the manufacturing process and reduce costs while ensuring the overall performance and reliability of the motor.

[0071] Specifically, the sleeve 102 and the stator body 101 adopt a transition fit or an interference fit. The transition fit or the interference fit can ensure a tight physical connection between the sleeve 102 and the stator body 101, thereby reducing the leakage of the coolant. Especially under high-pressure oil cooling conditions, this tight fit helps to improve the sealing performance, prevent the coolant from leaking into the non-cooling area of ​​the motor, and ensure the efficient operation of the cooling system.

[0072] The use of transition or interference fit increases the friction between the sleeve 102 and the stator body 101, thereby improving the mechanical connection strength between them. This design helps to resist the vibration generated when the motor is running and the centrifugal force generated under high-speed rotation, maintains a stable connection between the sleeve and the stator body, and reduces positional offset or structural looseness caused by mechanical movement.

[0073] It should be further explained that the stator body 101, the sleeve 102, the sealing ring 103, and the sealing bonding surface 104 constitute a cooling cavity. The sleeve 102 and the stator body 101 adopt a transition fit or an interference fit. The sleeve 102 is tightly fitted with the stator body 101 through at least one of a radial seal and an end face seal. The radial seal forms a seal in the radial direction (perpendicular to the axial direction) between the sleeve and the stator body through the sealing ring 103 and the sealing bonding surface 104 to prevent radial leakage of the coolant. The end face seal forms a seal between the end face of the sleeve and the end face of the stator body to prevent axial leakage of the coolant. The combination of radial seal + end face seal can form multiple sealing barriers, significantly improve the sealing performance of the entire system, and reduce the risk of leakage of the coolant in different directions.

[0074] A radial seal is adopted, and the sealing ring 103 is installed at the joint of the stator body 101 and the sleeve 102. The sealing ring 103 is usually made of an elastic material, such as rubber or silicone. Through its elastic deformation, it fits tightly on the contact surface of the stator body 101 and the sleeve 102 under high pressure to form an effective sealing barrier. The sealing bonding surface 104 is the contact surface between the stator body 101 and the sleeve 102, which is specially treated to enhance the sealing effect. The sealing bonding surface 104 can be coated with sealant or other bonding materials to ensure a tight fit between the stator body 101 and the sleeve 102, and prevent the coolant from leaking from these joints under high pressure.

[0075] Specifically, the sleeve 102 is preferably made of glass fiber and carbon fiber composite materials, and the wall thickness is preferably 0.8 to 1 mm. In order to further reduce the deformation of the sleeve 102 under the oil pressure state, carbon fiber can be preferably used as the main material, and the plying scheme is preferably mainly circumferential paving, which can better adapt to the annular structure of the cooling sleeve, enhance its annular strength, and maintain good sealing performance. The sleeve 102 is formed by processes such as autoclave, RTM (resin transfer molding) or compression molding to ensure that a good interface seal is formed between the sleeve 102 and the stator body 101, greatly reducing the risk of leakage.

[0076] It should be further explained that the molding of composite materials can be achieved through a variety of processes, including 3D weaving, woven fabric laying or unidirectional tape laying, short-cut fiber laying, etc. The choice of these processes depends on the specific design of the motor. In some cases, metals can also be used to replace composite materials, or plastics can be used to replace composite materials.

[0077] It should be further explained that the outer rotor motor further comprises a flange, and the flange consists of two parts: an upper flange 203 and a lower flange 204 .

[0078] like Figure 7As shown, bolts 001 pass through pre-drilled holes (or threaded holes) on the upper flange 203 and cooperate with corresponding threaded holes or nuts on the stator body 101 to fasten the upper flange 203 to the stator body 101. Bolt connection can provide higher mechanical strength and is suitable for occasions that need to withstand larger axial forces, such as resisting axial impact of oil pressure and vibration during motor operation.

[0079] The rivet 002 is used to connect and fix the lower flange 204 to the cooling sleeve 102 to enhance the structural rigidity and sealing performance and prevent the leakage of the coolant. The rivet connection is usually quick and simple.

[0080] In order to improve the overall flange fixing rigidity and achieve effective lightweight, it is preferred to use composite materials for one-piece molding, such as Figure 8 The upper flange 203 and the lower flange 204 shown may be in the form of a sandwich flange of composite material + plastic + composite material, which can effectively reduce the cost.

[0081] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0082] 1. Through the immersion cooling design, compared with the traditional spray cooling, the coolant directly contacts the winding in the slot, which greatly improves the heat exchange efficiency. At the same time, the arrangement of the axial cooling channel 108 ensures the uniformity of the cooling of the winding in the slot, effectively controls the temperature rise of the winding in the motor slot, and improves the operating efficiency and reliability of the motor.

[0083] 2. The composite material sleeve is combined with radial + end face sealing solutions, as well as sealing rings and sealing bonding surfaces to form a multi-layer sealing structure, which greatly reduces the possibility of coolant leakage. At the same time, it simplifies the sealing components, reduces the failure rate caused by sealing problems, and ensures the long-term stable operation of the oil cooling system.

[0084] 3. The use of glass fiber and carbon fiber composite materials as the main material of the sealing sleeve not only provides the necessary oil pressure resistance and reduces deformation, but can also effectively improve the inner diameter insulation effect of the motor stator oil cooling system and reduce the risk of leakage, and also realizes the lightweight of the overall structure and reduces costs.

[0085] The above embodiments may also be used in the technical field of aviation drive equipment. That is, according to another aspect of the present invention, an aviation drive system is provided, including an outer rotor motor, which is the outer rotor motor of any one of the above embodiments.

[0086] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0087] In addition to the above, it should be noted that "one embodiment", "another embodiment", "embodiment", etc. mentioned in this specification refer to the specific features, structures or characteristics described in conjunction with the embodiment included in at least one embodiment generally described in this application. The same expression appearing in multiple places in the specification does not necessarily refer to the same embodiment. Further, when describing a specific feature, structure or characteristic in conjunction with any embodiment, it is claimed that the realization of such feature, structure or characteristic in conjunction with other embodiments also falls within the scope of the present invention.

[0088] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0089] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An outer rotor motor, characterized in that: include: A stator body (101), wherein the stator body (101) is provided with an oil inlet (105) and an oil outlet (112), the stator body (101) having a plurality of stator slots extending along a first direction, in-slot windings (109) being wound in the stator slots, and an axial cooling channel (108) being formed between two in-slot windings (109) located in the same stator slot; A sleeve (102), wherein the sleeve (102) is located outside the stator body (101); The oil inlet (105) is in communication with a first end of the axial cooling channel (108), and the oil outlet (112) is in communication with a second end of the axial cooling channel (108).

2. The outer rotor motor according to claim 1, characterized in that: The end of the axial cooling channel (108) away from the output shaft of the outer rotor motor along the first direction forms a first end of the axial cooling channel (108), and the end of the axial cooling channel (108) close to the output shaft of the outer rotor motor along the first direction forms a second end of the axial cooling channel (108).

3. The outer rotor motor according to claim 2, characterized in that: The end of the in-slot winding (109) away from the output shaft along the first direction is a first winding end (107), and the end of the in-slot winding (109) close to the output shaft along the first direction is a second winding end (111), wherein a first end cooling loop (106) is formed between the first winding end (107), the stator body (101) and the sleeve (102), and a second end cooling loop (110) is formed between the second winding end (111), the stator body (101) and the sleeve (102), the first end cooling loop (106) is in communication with a first end of the axial cooling channel (108) and the oil inlet (105), and the second end cooling loop (110) is in communication with a second end of the axial cooling channel (108) and the oil outlet (112).

4. The outer rotor motor according to claim 1, characterized in that: The oil inlet (105) and the oil outlet (112) are symmetrically arranged at 180 degrees with respect to the central axis of the outer rotor motor when projected along the first direction.

5. The outer rotor motor according to any one of claims 1 to 4, characterized in that: The first direction is the axial direction of the stator body (101).

6. The outer rotor motor according to claim 1, characterized in that: There are a plurality of oil inlets (105), and the plurality of oil inlets (105) are arranged at intervals along the circumferential direction of the stator body (101); there are a plurality of oil outlets (112), and the plurality of oil outlets (112) are arranged at intervals along the circumferential direction of the stator body (101); the oil inlets (105) and the oil outlets (112) are arranged in pairs, and each of the oil inlets (105) and the corresponding oil outlet (112) are arranged symmetrically at 180 degrees with respect to the central axis of the outer rotor motor.

7. The outer rotor motor according to claim 3, characterized in that: At least one of a first region of the sleeve (102) opposite to the first winding end (107) and a second region of the sleeve (102) opposite to the second winding end (111) is a multilayer structure, the multilayer structure comprising a carbon fiber bearing layer (200) and a first glass fiber insulation layer (201) located inside the carbon fiber bearing layer (200), and a second glass fiber insulation layer (202) is further provided on the first glass fiber insulation layer (201) away from the carbon fiber bearing layer (200).

8. The outer rotor motor according to claim 7, characterized in that: The portion of the sleeve (102) located between the first region and the second region comprises a double-layer structure, wherein the double-layer structure comprises the carbon fiber bearing layer (200) and a first glass fiber insulation layer (201) located inside the carbon fiber bearing layer (200).

9. The outer rotor motor according to claim 1, characterized in that: The sleeve (102) and the stator body (101) adopt a transition fit or an interference fit.

10. An aviation drive system, comprising an outer rotor motor, characterized in that: The outer rotor motor is the outer rotor motor according to any one of claims 1 to 9.

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