Self-lubricating enameled wire and preparation method thereof

Abstract

The invention provides a self-lubricating enameled wire and a preparation method thereof, and belongs to the technical field of cables. The self-lubricating enameled wire comprises a metal core wire, a primer layer is coated outside the metal core wire, a surface paint layer is coated outside the primer layer, a self-lubricating layer is coated outside the surface paint layer, and the thickness of the self-lubricating layer is 0.002-0.004 mm. According to the enameled wire, through the arrangement of the self-lubricating layer, the friction coefficient of the enameled wire in the use process is remarkably reduced, the lubricity and wear resistance of the enameled wire are improved, and the service life of the enameled wire can be prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of cables, and in particular to a self-lubricating enameled wire and a preparation method thereof. Background Art

[0002] In the use of compressors, the performance requirements for enameled copper round wire are extremely strict. 200-grade polyamide-imide composite polyester or polyester-imide enameled copper round wire is widely used because of its excellent performance in heat resistance, mechanical properties, chemical properties, etc. With the continuous advancement of technology, compressor manufacturers vigorously promote high-speed winding equipment, which puts higher requirements on the winding performance of enameled wire, requiring the enameled wire to have good self-lubrication to adapt to the high-speed winding process. At the same time, the influence of environmental factors in industrial production is increasing, and the type of stator impregnation varnish has also undergone a major change. Traditional solvent-based impregnation varnish is gradually being replaced by more environmentally friendly water-based impregnation varnish due to its greater pollution to the environment. However, a key problem is exposed in the application process of water-based impregnation varnish, that is, the bonding force between it and the usual self-lubricating copper round enameled wire is much lower than that of solvent-based impregnation varnish, which is difficult to meet the actual production needs. This contradiction seriously restricts the further development of the compressor industry.

[0003] Therefore, it is necessary to improve the existing self-lubricating enameled wire to overcome the defects of the prior art. Summary of the invention

[0004] In order to overcome the problems existing in the related art, one of the purposes of the present invention is to provide a self-lubricating enameled wire, which, through the provision of a self-lubricating layer, significantly reduces the friction coefficient of the enameled wire during use, increases the lubricity and wear resistance of the enameled wire, and can extend the service life of the enameled wire.

[0005] A self-lubricating enameled wire comprises a metal core wire, the metal core wire is coated with a primer layer, the primer layer is coated with a topcoat layer, the topcoat layer is coated with a self-lubricating layer, and the thickness of the self-lubricating layer is 0.002mm-0.004mm.

[0006] The enameled wire can improve the strength and toughness of the enameled wire through the primer layer and the topcoat layer, so that it can withstand a certain amount of mechanical external force without the paint film breaking or falling off, ensuring that the enameled wire can maintain good mechanical integrity and ensure the stability of electrical performance. The setting of the self-lubricating layer reduces the friction coefficient of the enameled wire during use. In high-speed winding equipment, the friction between the enameled wire and the winding equipment components is reduced, which not only reduces the wear on the surface of the enameled wire and increases the service life of the enameled wire, but also reduces the energy consumption during the winding process and improves production efficiency.

[0007] In a preferred technical solution of the present invention, the primer layer includes polyesterimide, the topcoat layer includes polyamideimide, and the self-lubricating layer includes self-lubricating polyamideimide.

[0008] The polyesterimide of the primer layer and the polyamideimide of the topcoat layer each have a high heat resistance index and can maintain stable physical and chemical properties in high temperature environments. When the enameled wire is used in equipment such as motors and transformers, even if the equipment generates a lot of heat during long-term operation, the paint film of the enameled wire will not easily soften, break down or fall off, effectively ensuring the safe and stable operation of the equipment and extending the service life of the equipment.

[0009] In the application scenario of water-based impregnation varnish, self-lubricating polyamide-imide is used as the outermost self-lubricating layer of the enameled wire, which is coated by a specific process (thickness is about 0.002-0.004mm), which helps to improve the adhesion of the enameled wire to the water-based impregnation varnish. Compared with traditional self-lubricating materials or coatings, it can better adapt to the characteristics of water-based impregnation varnish, so that the enameled wire forms a tighter and firmer bond with the water-based impregnation varnish during the impregnation process, ensuring the insulation performance and overall performance stability of components such as the motor stator after impregnation.

[0010] In a preferred technical solution of the present invention, the polyesterimide content of the primer layer is 60%-70%.

[0011] In a preferred technical solution of the present invention, the heat resistance index of the polyesterimide of the primer layer is greater than 200, and the primer layer is formed by 10-14 coating and drying processes.

[0012] This application controls the proportion of polyesterimide in the primer layer to 60%-70%, while ensuring that the primer layer has good performance, it effectively takes into account the material cost. Compared with the use of a higher proportion of polyesterimide, it can reduce the cost of raw material procurement, improve production efficiency, and make the product have a cost advantage in market competition without sacrificing the key performance of the enameled wire due to cost reduction. Since the heat resistance index of polyesterimide is greater than 200, and after multiple coating and drying processes, the primer layer can form a dense paint film structure, which greatly enhances the heat resistance of the enameled wire.

[0013] In a preferred technical solution of the present invention, the polyamide-imide content of the surface paint layer is 30%-40%.

[0014] In a preferred technical solution of the present invention, the heat resistance index of the polyamide-imide of the topcoat layer is greater than 220, and the primer layer is formed by 5-8 coating and drying processes.

[0015] Controlling the proportion of polyamide-imide in the surface paint layer to 30%-40% can not only give full play to its excellent heat resistance and chemical properties, but also reasonably control the material cost. Compared with the use of a higher proportion of polyamide-imide, without reducing the overall performance of the enameled wire, the raw material procurement cost is reduced and the market competitiveness of the product is improved.

[0016] Since the heat resistance index of polyamide-imide is greater than 220, and the surface paint layer formed after 5-8 coating and drying processes has a dense structure, the heat resistance of the enameled wire is greatly enhanced.

[0017] In a preferred technical solution of the present invention, the total thickness of the primer layer, the topcoat layer and the self-lubricating layer is 0.03 mm-0.08 mm.

[0018] The total thickness of the paint layer designed in this application is within the range of 0.03mm-0.08mm, which can provide good electrical insulation protection for the metal core wire. In electrical equipment, enameled wire is used as the insulation layer of the conductive parts. This thickness can effectively prevent current leakage, ensure the electrical safety and stability of the equipment, reduce the risk of short circuits, leakage and other faults caused by poor insulation, and improve the reliability and service life of the equipment.

[0019] Moreover, the total thickness of the paint layer is in the range of 0.03mm-0.08mm, which avoids the waste of materials and increased costs caused by too thick a paint layer, and also prevents the problem of the paint layer being too thin and unable to meet the performance requirements.

[0020] In a preferred technical solution of the present invention, the thickness ratio of the primer layer to the topcoat layer is 3:2-5:4.

[0021] The thickness ratio of the primer layer to the topcoat layer of the present application is between 3:2-5:4, which can give full play to the performance advantages of the two paint layer materials and cooperate with each other. The polyesterimide primer layer lays the foundation for the enameled wire with its good adhesion and certain heat resistance, and the polyamideimide topcoat layer provides outer layer protection with its excellent heat resistance and chemical properties. The two form a tightly combined structure at a specific thickness ratio, effectively improving the overall heat resistance, mechanical strength and chemical stability of the enameled wire.

[0022] A second object of the present invention is to provide a method for preparing a self-lubricating enameled wire, which is used to prepare the self-lubricating enameled wire as described above.

[0023] In a preferred technical solution of the present invention, the method comprises the following steps:

[0024] The method comprises the following steps:

[0025] Get the metal core wire;

[0026] Apply multiple coats of polyesterimide on the metal core wire and dry it to form a primer layer;

[0027] Specifically, during the polyester imide coating process, 10 to 14 polyester imide coating and drying processes are performed, and after the last polyester imide coating is completed, the polyester imide is sent to a drying oven for curing at 600°C to 630°C;

[0028] Applying multiple layers of polyamide-imide on the primer layer and drying them to form a topcoat layer;

[0029] Among them, the polyamide-imide coating process is carried out according to 5-8 coating and drying processes. After the last polyamide-imide coating is completed, it is sent to the oven for curing at 600℃-630℃;

[0030] Applying multiple layers of self-lubricating polyamide-imide on the topcoat layer and drying the layers to form a self-lubricating layer;

[0031] Among them, the self-lubricating polyamide-imide is coated with one layer and cured at 600°C-630°C, and a lubricant is coated on the cured self-lubricating layer.

[0032] The beneficial effects of the present invention are:

[0033] The present invention provides a self-lubricating enameled wire, which includes a metal core wire, a primer layer coated on the outside of the metal core wire, a topcoat layer coated on the outside of the primer layer, a self-lubricating layer coated on the outside of the topcoat layer, and a thickness of the self-lubricating layer of 0.002mm-0.004mm. The enameled wire can improve the strength and toughness of the enameled wire through the primer layer and the topcoat layer, so that it can withstand a certain mechanical external force without the paint film breaking or falling off, ensuring that the enameled wire can maintain good mechanical integrity and ensure the stability of electrical performance. The provision of the self-lubricating layer reduces the friction coefficient of the enameled wire during use. In high-speed winding equipment, the friction between the enameled wire and the winding equipment components is reduced, which not only reduces the wear on the surface of the enameled wire and increases the service life of the enameled wire, but also reduces the energy consumption during the winding process and improves production efficiency. The thickness of the self-lubricating layer is between 0.002mm-0.004mm, which can ensure sufficient lubrication effect without affecting other properties of the enameled wire or increasing unnecessary costs due to excessive thickness.

[0034] The present application also provides a method for preparing the above-mentioned self-lubricating enameled wire. The enameled wire prepared by the method has higher strength and toughness, and the friction between the wire and the winding equipment components is reduced, and the wire is not easy to wear during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram of a self-lubricating enameled wire provided in an embodiment of the present invention;

[0036] Figure 2 is a schematic diagram of a self-lubricating enameled wire including a connection grid provided in an embodiment of the present invention;

[0037] Figure 3 Detailed description of the invention The figure is a flow chart of a method for preparing a self-lubricating enameled wire provided in an embodiment of the present invention.

[0038] Reference numerals:

[0039] 1. Metal core wire; 2. Primer layer; 3. Surface paint layer; 4. Self-lubricating layer; 5. Connection grid; DETAILED DESCRIPTION

[0040] The preferred embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0041] In the use of compressors, the performance requirements for enameled copper round wire are extremely strict. 200-grade polyamide-imide composite polyester or polyester-imide enameled copper round wire is widely used because of its excellent performance in heat resistance, mechanical properties, chemical properties, etc. With the continuous advancement of technology, compressor manufacturers vigorously promote high-speed winding equipment, which puts higher requirements on the winding performance of enameled wire, requiring the enameled wire to have good self-lubrication to adapt to the high-speed winding process. At the same time, the influence of environmental factors in industrial production is increasing, and the type of stator impregnation varnish has also undergone a major change. Traditional solvent-based impregnation varnish is gradually being replaced by more environmentally friendly water-based impregnation varnish due to its greater pollution to the environment. However, a key problem is exposed in the application process of water-based impregnation varnish, that is, the bonding force between it and the usual self-lubricating copper round enameled wire is much lower than that of solvent-based impregnation varnish, which is difficult to meet the actual production needs. This contradiction seriously restricts the further development of the compressor industry.

[0042] Based on this, the present application provides a self-lubricating enameled wire.

[0043] Example 1

[0044] See also Figure 1-Figure 2 The present embodiment provides a self-lubricating enameled wire, comprising a metal core wire 1, the metal core wire 1 is coated with a primer layer 2, the primer layer 2 is coated with a topcoat layer 3, the topcoat layer 3 is coated with a self-lubricating layer 4, and the thickness of the self-lubricating layer 4 is 0.002mm-0.004mm.

[0045] The enameled wire can improve the strength and toughness of the enameled wire through the primer layer 2 and the topcoat layer 3, so that it can withstand a certain mechanical external force without the paint film breaking or falling off, ensuring that the enameled wire can maintain good mechanical integrity and ensure the stability of electrical performance. The provision of the self-lubricating layer 4 reduces the friction coefficient of the enameled wire during use. In high-speed winding equipment, the friction between the enameled wire and the winding equipment components is reduced, which not only reduces the wear on the surface of the enameled wire and increases the service life of the enameled wire, but also reduces the energy consumption during the winding process and improves production efficiency.

[0046] The thickness of the self-lubricating layer 4 is between 0.002 mm and 0.004 mm, which can ensure sufficient lubrication effect without affecting other properties of the enameled wire or increasing unnecessary costs due to excessive thickness.

[0047] Specifically, the material of the self-lubricating layer 4 in this embodiment can be any one of polyesterimide, polyester, polyamideimide, polytetrafluoroethylene or polyimide.

[0048] Example 2

[0049] This embodiment is optimized based on embodiment 1.

[0050] See also Figure 1-Figure 2 In this embodiment, the primer layer 2 includes polyesterimide, the topcoat layer 3 includes polyamideimide, and the self-lubricating layer 4 includes self-lubricating polyamideimide.

[0051] The polyesterimide of the primer layer 2 and the polyamideimide of the topcoat layer 3 each have a high heat resistance index and can maintain stable physical and chemical properties in a high temperature environment. When the enameled wire is used in equipment such as motors and transformers, even if the equipment generates a lot of heat during long-term operation, the paint film of the enameled wire will not easily soften, break down or fall off, effectively ensuring the safe and stable operation of the equipment and extending the service life of the equipment.

[0052] In the application scenario of water-based impregnation varnish, self-lubricating polyamide-imide is used as the outermost self-lubricating layer of the enameled wire, which is coated by a specific process (thickness is about 0.002-0.004mm), which helps to improve the adhesion of the enameled wire to the water-based impregnation varnish. Compared with traditional self-lubricating materials or coatings, it can better adapt to the characteristics of water-based impregnation varnish, so that the enameled wire forms a tighter and firmer bond with the water-based impregnation varnish during the impregnation process, ensuring the insulation performance and overall performance stability of components such as the motor stator after impregnation.

[0053] Example 3

[0054] This embodiment is improved on the basis of Implementation 2.

[0055] See also Figure 1-Figure 2Specifically, in this embodiment, the polyesterimide content of the primer layer 2 is 60%-70%.

[0056] In this embodiment, the heat resistance index of the polyesterimide of the primer layer 2 is greater than 200, and the primer layer 2 is formed by 10-14 coating and drying processes.

[0057] This application controls the proportion of polyesterimide in the primer layer 2 to 60%-70%, while ensuring that the primer layer 2 has good performance, it effectively takes into account the material cost. Compared with the use of a higher proportion of polyesterimide, it can reduce the cost of raw material procurement, improve production efficiency, and make the product have a cost advantage in market competition without sacrificing the key performance of the enameled wire due to cost reduction. Since the heat resistance index of polyesterimide is greater than 200, and after multiple coating and drying processes, the primer layer 2 can form a dense paint film structure, which greatly enhances the heat resistance of the enameled wire.

[0058] Moreover, the 10-14 coating and drying processes form a close bond between the primer layer 2 and the metal core wire 1, which enhances the mechanical stability of the enameled wire. During the winding, installation and use of the enameled wire, it can withstand certain mechanical stresses, such as bending, stretching, etc., without the paint film falling off or being damaged. This not only improves the processing efficiency and product quality in the production process and reduces the scrap rate, but also ensures the reliability of the enameled wire in the long-term operation of the equipment and maintains stable electrical performance.

[0059] More specifically, the primer layer 2 includes a small amount of coupling agent in addition to polyesterimide. The coupling agent can form a chemical bond or physical adsorption between the polyesterimide and the metal surface, improve the interface bonding state between the two, and make the primer layer 2 more firmly attached to the metal core wire 1.

[0060] Example 4

[0061] This embodiment is improved on the basis of Implementation 2.

[0062] See also Figure 1-Figure 2 In this embodiment, the polyamide-imide content of the topcoat layer 3 is 30%-40%.

[0063] More preferably, in this embodiment, the heat resistance index of the polyamide-imide of the topcoat layer 3 is greater than 220, and the primer layer 2 is formed by a coating and drying process of 5 to 8 layers.

[0064] Controlling the proportion of polyamide-imide in the topcoat layer 3 to 30%-40% can not only give full play to its excellent heat resistance and chemical properties, but also reasonably control the material cost. Compared with the use of a higher proportion of polyamide-imide, the raw material procurement cost is reduced without reducing the overall performance of the enameled wire, and the market competitiveness of the product is improved.

[0065] Since the heat resistance index of polyamide-imide is greater than 220, and the surface paint layer 3 formed after 5-8 coating and drying processes has a dense structure, the heat resistance of the enameled wire is greatly enhanced.

[0066] Example 5

[0067] This embodiment is improved on the basis of Implementation 2.

[0068] In this embodiment, the total thickness of the primer layer 2, the topcoat layer 3, and the self-lubricating layer 4 is 0.03 mm-0.08 mm.

[0069] The total thickness of the paint layer designed in this application is within the range of 0.03mm-0.08mm, which can provide good electrical insulation protection for the metal core wire 1. In electrical equipment, the enameled wire is used as the insulating layer of the conductive part. This thickness can effectively prevent current leakage, ensure the electrical safety and stability of the equipment, reduce the risk of short circuits, leakage and other faults caused by poor insulation, and improve the reliability and service life of the equipment.

[0070] Moreover, the total thickness of the paint layer is in the range of 0.03mm-0.08mm, which avoids the waste of materials and increased costs caused by too thick a paint layer, and also prevents the problem of the paint layer being too thin and unable to meet the performance requirements.

[0071] More preferably, in this embodiment, the thickness ratio of the primer layer 2 to the topcoat layer 3 is 3:2-5:4.

[0072] The thickness ratio of the primer layer 2 to the topcoat layer 3 of the present application is between 3:2-5:4, which can give full play to the performance advantages of the two paint layer materials and cooperate with each other. The polyesterimide primer layer 2 lays the foundation for the enameled wire with its good adhesion and certain heat resistance, and the polyamideimide topcoat layer 3 provides outer layer protection with its excellent heat resistance and chemical properties. The two form a tightly combined structure at a specific thickness ratio, effectively improving the overall heat resistance, mechanical strength and chemical stability of the enameled wire.

[0073] In a more preferred embodiment, a connecting grid 5 is further provided between the primer layer 2 and the topcoat layer 3 , and the connecting grid 5 extends from the inside to the outside along the radial direction of the metal core wire 1 .

[0074] Specifically, the connecting grid 5 can select high-strength, high-temperature-resistant and chemically stable metal or alloy fibers, such as stainless steel fibers or nickel-based alloy fibers, and determine the appropriate fiber length and weaving method according to the size and performance requirements of the enameled wire to form a connecting grid 5 with good mechanical properties and thermal conductivity.

[0075] During the preparation process, on the surface of the cured primer layer 2, the pre-prepared connecting grid 5 is carefully installed and fixed in a suitable position using an auxiliary device to ensure that the connecting grid 5 extends radially from the inside to the outside along the metal core wire 1 and is evenly distributed, and has good contact and bonding with the primer layer 2, and can effectively transfer stress and heat.

[0076] Among them, the presence of the connection grid 5 significantly improves the mechanical strength and toughness of the enameled wire. When the enameled wire is subjected to mechanical stress such as bending, stretching, and torsion, the connection grid 5 can effectively disperse the stress, prevent the paint film from being damaged by cracks, peeling, and the like, and improve the reliability and stability of the enameled wire in a complex mechanical environment. For example, during the winding and installation of the motor winding, the enameled wire needs to withstand a certain mechanical operating force. At this time, the connection grid 5 can effectively protect the paint layer structure and reduce the risk of electrical performance degradation and failure caused by mechanical damage.

[0077] Example 6

[0078] This embodiment provides a method for preparing a self-lubricating enameled wire, which is used to prepare the self-lubricating enameled wire as described above.

[0079] See also Figure 1-Figure 3 Specifically, the method comprises the following steps:

[0080] The method comprises the following steps:

[0081] S100, obtaining a metal core wire 1;

[0082] S200, coating a plurality of layers of polyester imide on the metal core wire 1 and drying the same to form a primer layer 2;

[0083] Specifically, during the polyester imide coating process, 10 to 14 polyester imide coating and drying processes are performed, and after the last polyester imide coating is completed, the polyester imide is sent to a drying oven for curing at 600°C to 630°C;

[0084] S300, coating multiple layers of polyamide-imide on the primer layer 2 and drying to form a topcoat layer 3;

[0085] Among them, the polyamide-imide coating process is carried out according to 5-8 coating and drying processes. After the last polyamide-imide coating is completed, it is sent to the oven for curing at 600℃-630℃;

[0086] S400, coating multiple layers of self-lubricating polyamide-imide on the topcoat layer 3 and drying to form a self-lubricating layer 4;

[0087] Among them, self-lubricating polyamide-imide is coated with one coat and cured at 600℃-630℃.

[0088] A lubricant is coated on the cured self-lubricating layer 4 .

[0089] Specifically, the preparation method of the self-lubricating enameled wire of the present application is as follows:

[0090] 1. Material preparation process:

[0091] Obtaining metal core wire 1: Select high-quality copper material with a diameter of 10 mm, which is finely drawn and annealed to ensure that its surface is smooth, free of impurities, and has good conductivity and flexibility, providing a solid foundation for subsequent paint coating.

[0092] Primer layer 2 material: polyester imide is used, of which polyester imide accounts for 60%-70%, and is formulated according to a strict process formula to ensure that its proportion in the primer layer 2 meets the requirements and has good thermal stability and adhesion.

[0093] Surface paint layer 3 material: polyamide-imide is selected, wherein the proportion of polyamide-imide is 30%-40%, the heat resistance index is greater than 220, the purity and chemical properties are stable, and the proportion in the surface paint layer 3 is precisely controlled within a predetermined range to achieve optimal performance.

[0094] Self-lubricating layer 4 material: self-lubricating polyamide-imide, with uniform particle size, can form a smooth and stable lubricating layer after coating, and the thickness of the self-lubricating layer 4 can be accurately controlled between 0.002-0.004mm.

[0095] Coating equipment: Equipped with a high-precision enameled wire coating system, including a paint supply device that can accurately control flow and pressure, a paint rack that can achieve uniform coating, and a drying oven with precise temperature control and ventilation functions to ensure the consistency of coating thickness and curing effect of each paint layer.

[0096] 2. Preparation process:

[0097] Primer layer 2 coating: The pretreated metal core wire 1 is mounted on the coating equipment, and the paint supply system is started to evenly coat the surface of the metal core wire 1 with polyesterimide paint. The thickness of the primer layer 2 is precisely controlled within a corresponding proportion of the total thickness range by adjusting the coating speed, the paint flow rate, and the number of coating passes. In one embodiment, after the coating is completed, it can be immediately sent to a drying oven for curing. The curing temperature and time are set according to the characteristics of polyesterimide to ensure that the primer layer 2 is fully cross-linked to form a stable paint film structure.

[0098] In another embodiment, no coat of polyester imide paint is applied and the curing is performed.

[0099] Coating of topcoat layer 3: On the surface of the cured primer layer 2, a polyamide-imide topcoat layer 3 is coated again using a coating device. During the coating process, the thickness and uniformity of the paint layer are closely monitored, and the coating parameters are adjusted according to the total thickness requirements to ensure that the topcoat layer 3 is closely combined with the primer layer 2 and the thickness meets the design standards. After coating, it is sent to a drying oven for curing. The curing conditions are compatible with the curing of the primer layer 2 to enhance the overall performance of the enameled wire.

[0100] Self-lubricating layer 4 coating: A special micro-coating process is used to coat the self-lubricating polyamide-imide paint on the surface of the topcoat layer 3. A high-precision coating mold and flow control system are used to ensure that the thickness of the self-lubricating layer 4 is between 0.002-0.004mm and that it is firmly bonded to the topcoat layer 3. After coating, it is cured in an oven to maintain its self-lubricating performance and stability.

[0101] 3. Thickness detection and adjustment

[0102] After each layer of paint is applied and cured, the paint thickness is tested using a high-precision coating thickness measuring instrument. If the thickness is found to be beyond the predetermined range, the parameters of the coating equipment, such as the paint flow rate, coating speed, etc., are adjusted in time to correct the subsequent coating process to ensure that the total thickness of the primer layer 2, the topcoat layer 3 and the self-lubricating layer 4 is always maintained between 0.03mm-0.08mm, ensuring the performance consistency and stability of the enameled wire.

[0103] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings. In the description of the present application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0104] 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.

[0105] In addition, it should be noted that the use of words such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above words have no special meaning and therefore cannot be understood as limiting the scope of protection of this application. 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 changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A self-lubricating enameled wire, comprising a metal core wire (1), characterized in that: The metal core wire (1) is coated with a primer layer (2), the primer layer (2) is coated with a topcoat layer (3), the topcoat layer (3) is coated with a self-lubricating layer (4), and the thickness of the self-lubricating layer (4) is 0.002 mm-0.004 mm.

2. The self-lubricating enameled wire according to claim 1, characterized in that: The primer layer (2) comprises polyesterimide, the topcoat layer (3) comprises polyamideimide, and the self-lubricating layer (4) comprises self-lubricating polyamideimide.

3. The self-lubricating enameled wire according to claim 2, characterized in that: The polyesterimide content of the primer layer (2) is 60%-70%.

4. The self-lubricating enameled wire according to claim 3, characterized in that: The polyester imide of the primer layer (2) has a heat resistance index greater than 200, and the primer layer (2) is formed by a coating and drying process of 10 to 14 passes.

5. The self-lubricating enameled wire according to claim 2, characterized in that: The polyamide-imide content of the surface paint layer (3) is 30%-40%.

6. The self-lubricating enameled wire according to claim 5, characterized in that: The heat resistance index of the polyamide-imide of the topcoat layer (3) is greater than 220, and the primer layer (2) is formed by a coating and drying process of 5 to 8 layers.

7. The self-lubricating enameled wire according to any one of claims 1 to 6, characterized in that: The total thickness of the primer layer (2), the topcoat layer (3) and the self-lubricating layer (4) is 0.03 mm to 0.08 mm.

8. The self-lubricating enameled wire according to claim 7, characterized in that: The thickness ratio of the primer layer (2) to the topcoat layer (3) is 3:2-5:

4.

9. A method for preparing a self-lubricating enameled wire, characterized in that: Used for preparing the self-lubricating enameled wire as claimed in any one of claims 1 to 8.

10. The method for preparing the self-lubricating enameled wire according to claim 9, characterized in that: The method comprises the following steps: Obtaining a metal core wire (1); Coating multiple layers of polyester imide on the metal core wire (1) and drying to form a primer layer (2); Coating multiple layers of polyamide-imide on the primer layer (2) and drying to form a topcoat layer (3); Coating multiple layers of self-lubricating polyamide-imide on the topcoat layer (3) and drying to form a self-lubricating layer (4); A lubricant is coated on the cured self-lubricating layer (4).

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