Self-bonding enameled flat copper wire and method for manufacturing the same

Abstract

The present application relates to a kind of self-bonding enameled flat copper wire, including copper conductor and the base insulating layer and self-bonding insulating layer covered in copper conductor outside in turn from inside to outside;Self-bonding insulating layer can be automatically bonded with each other between adjacent bonding insulating layer when winding;The outermost self-bonding insulating varnish film of the flat copper wire is self-bonding, after the product is heated by passing through power heating or hot air heating mode, self-bonding insulating varnish film is heated to complete self-bonding function, and the shape of flat wire winding is automatically fixed and formed, after natural cooling, keep the mechanical properties, moisture resistance and chemical stability of motor flat wire winding complete, no additional plant equipment investment, various expensive professional large equipment, and a large number of professionals are needed in the process of completing self-bonding, while there is no noise, chemical pollution and other environmental pollution problems in the operation process.

Description

Technical Field

[0001] This invention relates to the field of enameled wire production, and more particularly to a self-adhesive enameled flat copper wire and its preparation method. Background Technology

[0002] The current process flow for the impregnation method of flat wire motor windings is as follows: preheating, impregnation, and drip drying. After the motor windings are preheated to remove moisture and cooled, they are placed in a vacuum environment to remove air and volatiles from the windings. Relying on the gravity of the impregnating varnish in the vacuum and the capillary action of the coil, as well as the application of a certain pressure to the impregnating varnish after the vacuum is removed using dry compressed air or inert gas, the varnish quickly penetrates and fills the inner layer of the insulation structure. After the motor windings are evenly impregnated, the motor components are left to drip dry. After the impregnating varnish has dripped dry, it is transferred to a separate oven for vacuum drying, atmospheric pressure static drying, or rotary drying.

[0003] Therefore, existing impregnation and drying technologies face the following problems in the production process: 1. They require the construction of dedicated factory buildings or production workshops; 2. They require expensive and professional impregnation and drying equipment; 3. The entire impregnation process is very complex and requires a large number of professional operators; 4. They pose serious environmental pollution and health risks to operators. Therefore, the existing flat wire motor impregnation and drying process has very obvious disadvantages in terms of site construction, capital investment, environmental protection, and health and safety issues. Furthermore, existing enameled flat wires, after being wound into motor windings, require impregnation and drying processes on the shaped motor windings to fix the winding coil shape, enhance mechanical strength, improve winding thermal conductivity, and increase the motor's moisture and chemical resistance. During the impregnation and drying process, a large amount of toxic and harmful solvents in the impregnation varnish evaporate into the air, causing air pollution and harming the health of workers. This invention eliminates the impregnation and drying process after motor winding, preventing pollution from toxic and harmful volatile gases. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a self-adhesive enameled flat copper wire and its preparation method. The outermost self-adhesive insulating varnish film of this flat copper wire, after being heated by electric heating or hot air heating, completes its self-adhesive function, automatically fixing the shape of the flat wire winding. After natural cooling, it maintains the complete mechanical properties, moisture resistance, and chemical stability of the motor flat wire winding. The self-adhesive process requires no additional investment in factory equipment, expensive specialized large-scale equipment, or a large number of professional personnel. Furthermore, the operation generates no noise, chemical pollution, or other environmental pollution problems.

[0005] The technical solution of the present invention is as follows: A self-adhesive enameled flat copper wire includes a copper conductor and a base insulation layer and a self-adhesive insulation layer sequentially wrapped around the copper conductor from the inside out; during winding, adjacent self-adhesive insulation layers can automatically bond to each other after being heated.

[0006] The self-adhesive insulating layer is made of semi-aromatic nylon produced by the condensation polymerization of aliphatic diamines and aromatic diacids.

[0007] The basic insulating layer is one or more of the following: modified polyester single coating, polyesterimide single coating, modified polyester composite polyamide-imide coating, polyesterimide composite polyamide-imide coating, polyamide-imide single coating, or polyimide single coating.

[0008] A method for preparing self-adhesive enameled flat copper wire includes the following steps: ① Semi-finished copper billets are drawn to specified specifications and then fed into the copper billets in real time via a wire feeding device; ② Based on the copper conductor size and shape specified by the customer, online precision drawing is performed using a custom-made polycrystalline wire drawing die to produce a square copper conductor with a smooth surface and stable dimensions. ③ The drawn square copper conductor is annealed and softened in a high-temperature non-contact annealing furnace to improve the ductility and stability of various mechanical properties of the copper conductor. ④ Based on the insulation structure requirements and insulation layer thickness requirements specified by the customer, use professional painting molds to perform separate, cyclic painting. ⑤ Use a high-temperature hot air circulating oven to bake and cure the insulating varnish, so that the liquid insulating varnish can fully cross-link under high temperature conditions to form a solid varnish film; ⑥ Use a high-speed turbine fan to blow in a large amount of cold air to quickly and forcibly cool the product, thereby improving the stability of the paint film; ⑦ The surface quality of finished enameled wire products is monitored in real time using high-precision online testing instruments; ⑧ Use the reel specified by the customer to wind up and package the finished enameled wire.

[0009] The painting mold includes a hollow mold sleeve and a hollow mold core detachably fitted at the front end of the mold sleeve; the inner diameter of the mold sleeve is larger than the size of the semi-finished flat wire to be painted; the semi-finished flat wire passes forward from the rear end of the mold sleeve through the mold sleeve and the mold core; the mold sleeve is filled with paint liquid; the inner diameter of the mold core gradually decreases along the direction of the semi-finished flat wire until the end opening is slightly larger than the size of the semi-finished flat wire, and the shape of the end opening of the mold core is the same as the shape of the semi-finished flat wire; the outer surface of the mold sleeve is provided with a groove for mounting on a machine base.

[0010] The mold core end opening is fitted with a thermistor ring; a heat-conducting ring is fitted around the thermistor ring at intervals; multiple semiconductor cooling chips are connected between the thermistor ring and the heat-conducting ring; the semiconductor cooling chips forcibly transfer heat energy between the thermistor ring and the heat-conducting ring; a guide ring is provided on the outer end face of the thermistor ring; the inner surface of the guide ring has an arc surface that smoothly convexes towards one side of the semi-finished flat wire along the axis of the semi-finished flat wire, and the inner diameter gradually decreases from the end away from the mold core end opening to the end closer to the mold core end opening; the inner surface of the thermistor ring also has an arc surface that smoothly convexes towards one side of the semi-finished flat wire along the axis of the semi-finished flat wire. The side has a smooth, convex arc surface, and its inner diameter gradually decreases from the end away from the mold core end opening to the end closer to the mold core end opening; the junction of the inner ring of the heat-sensitive ring and the inner ring of the heat-conducting ring forms an obtuse angle; the outer end of the air guide ring has an annular first air outlet slit attached along its circumference; the first air outlet slit connects to an annular first air guide cavity; one or more first air inlet pipes pressurize and introduce air into the first air guide cavity; a comma-shaped air distribution block is arranged along the circumference of the first air guide cavity; the air distribution block divides the first air guide cavity into an air pressurization cavity and an air acceleration cavity; the first air outlet slit connects to the outlet end of the air acceleration cavity.

[0011] The device includes a blower located outside the air guide ring and outside the two short sides of the semi-finished flat wire. The blower includes a flat annular second air outlet slit extending along the length of the semi-finished flat wire. The second air outlet slit connects to a second annular air guide cavity. One or more second air inlet pipes pressurize and introduce air into the second air guide cavity. The second air outlet slit blows out a flat, elongated annular air film towards the semi-finished flat wire, and drives the air behind the second air outlet slit through the space enclosed by the second air outlet slit and blows it out towards the semi-finished flat wire, forming a continuous planar air pressure.

[0012] The air entering the second air guide cavity is heated; a heating wire mesh is provided behind the second air outlet slit to heat the air that is blown out; the two long sides of the semi-finished flat wire are respectively provided with air guide hoods that gradually change from wide to narrow openings; the air guide hoods guide the airflow after the two air blowing devices collide to flow outward.

[0013] The mold sleeve includes a front painting section and a rear paint inlet section, with an inner sleeve fitted inside the paint inlet section. The front end of the inner sleeve is tapered and closely fits the surface of the semi-finished flat wire. The inner sleeve and the mold sleeve enclose a paint inlet cavity. A ring-shaped paint inlet piston is sealed and slidably fitted inside the paint inlet cavity. The paint inlet piston includes a shovel ring forming an outer ring, a relief ring near the inner ring, and a rear seat ring. The forward extension length of the shovel ring gradually decreases from the outer ring to the inner ring, forming a shovel head shape. The outer circumferential surface of the shovel ring is sealed to the inner wall of the mold sleeve. Sliding contact; the outer circumferential surface of the retraction ring and the inner circumferential surface of the shovel ring are sealed and slidingly contacted; the inner circumferential surface of the retraction ring and the outer circumferential surface of the inner sleeve are sealed and slidingly contacted; a spring is provided between the retraction ring and the rear seat ring; the shovel ring and the rear seat ring are fixedly connected or integrally formed; multiple linear drive rods are connected to the rear seat ring to drive the paint inlet piston to reciprocate back and forth along the paint inlet cavity; one or more paint inlets are provided on the mold sleeve to squeeze and supply paint into the paint inlet cavity; the reciprocating motion of the paint inlet piston periodically closes and opens the paint inlet.

[0014] A method for coating flat wires, using the aforementioned enameled flat wire coating mold, includes the following steps: ① The semi-finished flat wire passes through the inner sleeve, the front of the mold sleeve, the mold core, the heat-sensitive ring, and the air guide ring in sequence; the paint coating part of the mold sleeve and the paint inlet cavity are filled with paint liquid; the paint liquid is evenly adhered to the surface of the semi-finished flat wire in the paint coating part to form a paint film; ② During the painting process, the temperature of the thermistor ring is controlled by a semiconductor cooling chip, which causes the thermistor ring to expand and contract, thereby precisely controlling the inner diameter of the thermistor ring and thus controlling the thickness of the paint film. ③ During the painting process, the first air outlet slit blows out an annular airflow. Under the Coanda effect, the annular airflow adheres to the convex surface of the inner ring of the air guide ring and expands outward at the junction with the heat conduction ring at an obtuse angle, thereby forming a pushing air pressure. On the one hand, it shapes the paint film, and on the other hand, it reduces the situation where the paint liquid is squeezed out from the gap. ④ During the painting process, the heated annular air film is squeezed outward from the second air outlet slit, and the air heated by the heated wire mesh behind it is driven forward through the space enclosed by the second air outlet slit. This creates air pressure on the two short sides of the semi-finished flat wire, pushing the excess paint liquid to flow to the long side, preventing the paint liquid from accumulating at the corners of the semi-finished flat wire and causing the paint film to become "bone-like", and also preventing the paint film in the central part of the long side of the semi-finished flat wire from becoming thin. ⑤ During the painting process, the linear drive rod pushes the paint inlet piston forward in the paint inlet chamber, and the shovel ring moves forward and seals the paint inlet. During this process, the retracting ring pushes the spring backward to make room and make up for the space occupied by the shovel ring during its forward movement. This prevents the paint from being squeezed back to the paint inlet before the shovel ring closes the paint inlet. It also reduces excessive pressure on the mold sleeve and the paint in the paint inlet chamber, which can cause excessive paint pressure. When the paint inlet piston moves forward to its limit, it retracts and returns, allowing the paint inlet to re-expose and replenish the paint. At the same time, it creates a certain negative pressure in the paint inlet chamber. This negative pressure causes the paint squeezed into the gap between the mold core and the semi-finished flat wire to shrink back, preventing it from depositing and solidifying in that area.

[0015] The present invention has the following beneficial effects: 1. The outermost self-adhesive insulating varnish film of the flat copper wire of this invention, after being heated by electric heating or hot air heating, completes its self-adhesive function, automatically fixing the shape of the flat wire winding. After natural cooling, it maintains the complete mechanical properties, moisture resistance, and chemical stability of the motor flat wire winding. The self-adhesive process requires no additional investment in factory buildings, expensive large-scale specialized equipment, or a large number of professional personnel. Furthermore, the operation generates no noise, chemical pollution, or other environmental pollution problems.

[0016] 2. The coating mold of this invention is equipped with a thermally sensitive ring, combined with a heat-conducting ring and a semiconductor cooling chip, which can quickly and accurately adjust and control the temperature of the thermally sensitive ring. This allows the thermal expansion and contraction of the thermally sensitive ring to control its inner diameter, thereby controlling the gap between the thermally sensitive ring and the surface of the semi-finished flat wire. This allows for control and adjustment of the paint film thickness, improving the uniformity and dimensional stability of the paint film, and reducing the occurrence of paint being squeezed out of the gap. Furthermore, the inner surface of the thermally sensitive ring is a special inclined surface. Combined with the design of the air guide ring and the first air outlet slit, the Coanda effect is utilized to cause the annular air film blown out of the first air outlet slit to adhere to the inclined surface of the inner ring of the air guide ring and flow. It then impacts the obtuse angle at the junction with the thermally sensitive ring and rapidly diffuses outward, forming a pushing air pressure. This serves two purposes: shaping the paint film and reducing the occurrence of paint being squeezed out of the gap.

[0017] 3. The painting mold of the present invention has second air outlet slits on both sides of the short side of the semi-finished flat wire. The second air outlet slits extrude heated annular air film outwards, and drive the air heated by the heated wire mesh behind it through the space enclosed by the second air outlet slits forward, thereby creating air pressure on the two short sides of the semi-finished flat wire, pushing excess paint liquid to flow towards the long side, avoiding paint liquid accumulation at the corners of the semi-finished flat wire, which would cause the paint film to become "bone-like", and also preventing the paint film in the central part of the long side of the semi-finished flat wire from becoming thin; because the wind speed and pressure of the annular air film are higher than those of the central part... Because of the large fluid volume, the isobaric lines drawn based on the pressure are concave arcs that match the short side arc surface of the semi-finished flat wire. Therefore, the air pressure generated by the second air outlet slit on the short side of the semi-finished flat wire can be evenly applied to the short side arc surface, thereby further improving the uniformity of the paint film on the semi-finished flat wire. Furthermore, since this design can blow out uniform hot air, and the hot air temperature is simple and controllable, the drying process or the preliminary drying and shaping process can be completed simultaneously, thus simplifying subsequent processing steps or providing effective pre-processing assurance.

[0018] 4. The painting mold of this invention uses an inner sleeve to divide the internal space of the mold sleeve into a painting section and a paint inlet section, and uses a specially designed paint inlet piston to realize the cyclic opening and closing of the paint inlet. Because the inlet piston is designed with a spade ring, a relief ring, a back seat ring and a spring, the relief ring can push the spring backward to make room during the forward movement, making up for the space occupied by the spade ring during the forward movement, thereby preventing the paint from being squeezed back to the paint inlet before the spade ring closes the paint inlet; at the same time, it also reduces the excessive pressure on the paint in the mold sleeve and the paint inlet cavity, which would cause the paint pressure to be too high; when the paint inlet piston moves forward to its limit, it retracts. The process returns, exposing the paint inlet again for replenishment of paint. Simultaneously, a negative pressure is created in the paint inlet cavity, causing the paint squeezed into the gap between the mold core and the semi-finished flat wire to retract, preventing deposition and solidification in that area. Furthermore, the reciprocating motion effectively replenishes the paint consumed during adhesive application and promotes paint flow, increasing friction between the paint and the surface of the semi-finished flat wire, thus helping the paint adhere firmly to the surface. It also ensures uniform paint composition, preventing dead zone deposition, solidified fragments, and impurities, thereby improving the uniformity, adhesion, and stability of the paint film. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the enameled flat copper wire of the present invention; Figure 2 This is the chemical reaction formula for the main components of the self-adhesive insulating layer of the present invention; Figure 3 This is a schematic flowchart of the preparation method of the self-adhesive enameled flat copper wire of the present invention; Figure 4 This is a schematic diagram of the flat wire coating mold of the present invention; Figure 5For the present invention Figure 4 Enlarged view of the position of circle A in the middle; Figure 6 For the present invention Figure 4 Enlarged view of the position of circle B in the middle; Figure 7 This is a schematic diagram of the operation of the blower device of the present invention.

[0020] The reference numerals in the figure are as follows: 1. Mold sleeve; 2. Mold core; 3. Semi-finished flat wire; 31. Copper conductor; 32. Basic insulation layer; 33. Self-adhesive insulation layer; 4. Paint liquid; 51. Thermistor ring; 52. Heat-conducting ring; 53. Semiconductor cooling chip; 54. Air guide ring; 55. First air outlet slit; 56. First air guide cavity; 57. Air distribution block; 61. Second air outlet slit; 62. Second air guide cavity; 63. Heating wire mesh; 64. Air guide cover; 7. Inner sleeve; 71. Paint inlet cavity; 72. Paint inlet piston; 73. Shovel ring; 74. Recessing ring; 75. Rear seat ring; 76. Spring; 77. Linear drive rod; 78. Paint inlet. Implementation

[0021] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0022] See Figure 1 A self-adhesive enameled flat copper wire includes a copper conductor 31 and a base insulation layer 32 and a self-adhesive insulation layer 33 sequentially covering the copper conductor 31 from the inside out; during winding, adjacent self-adhesive insulation layers 33 can automatically bond to each other after being heated.

[0023] See Figure 2 Furthermore, the self-adhesive insulating layer 33 is made of semi-aromatic nylon produced by the condensation polymerization of aliphatic diamine and aromatic diacid. Semi-aromatic nylon has self-adhesive properties when heated, and under appropriate solvent or heating conditions, it can bond the coil turns together to form a shape.

[0024] Furthermore, the basic insulation layer 32 is one or more of the following: modified polyester single coating, polyesterimide single coating, modified polyester composite polyamide-imide coating, polyesterimide composite polyamide-imide coating, polyamide-imide single coating, or polyimide single coating.

[0025] See Figure 3 A method for preparing self-adhesive enameled flat copper wire includes the following steps: ① Semi-finished copper billets are drawn to specified specifications and then fed into the copper billets in real time via a wire feeding device; ② Based on the copper conductor size and shape specified by the customer, online precision drawing is performed using a custom-made polycrystalline wire drawing die to produce a square copper conductor with a smooth surface and stable dimensions. ③ The drawn square copper conductor is annealed and softened in a high-temperature non-contact annealing furnace to improve the ductility and stability of various mechanical properties of the copper conductor. ④ Based on the insulation structure requirements and insulation layer thickness requirements specified by the customer, use professional painting molds to perform separate, cyclic painting. ⑤ Use a high-temperature hot air circulating oven to bake and cure the insulating varnish, so that the liquid insulating varnish can fully cross-link under high temperature conditions to form a solid varnish film; ⑥ Use a high-speed turbine fan to blow in a large amount of cold air to quickly and forcibly cool the product, thereby improving the stability of the paint film; ⑦ The surface quality of finished enameled wire products is monitored in real time using high-precision online testing instruments; ⑧ Use the reel specified by the customer to wind up and package the finished enameled wire.

[0026] See Figures 4 to 7 Furthermore, the painting mold includes a hollow mold sleeve 1 and a hollow mold core 2 detachably fitted at the front end of the mold sleeve 1; the inner diameter of the mold sleeve 1 is larger than the size of the semi-finished flat wire 3 to be painted; the semi-finished flat wire 3 passes forward from the rear end of the mold sleeve 1 through the mold sleeve 1 and the mold core 2; the mold sleeve 1 is filled with paint liquid 4; the inner diameter of the mold core 2 gradually decreases along the direction in which the semi-finished flat wire 3 passes until the end opening is slightly larger than the size of the semi-finished flat wire 3, and the shape of the end opening of the mold core 2 is the same as the shape of the semi-finished flat wire 3; the outer surface of the mold sleeve 1 is provided with a groove for mounting on the machine base.

[0027] Furthermore, a thermistor ring 51 is fitted over the opening at the end of the mold core 2; a heat-conducting ring 52 is fitted around the thermistor ring 51 at intervals; multiple semiconductor cooling chips 53 are connected between the thermistor ring 51 and the heat-conducting ring 52; the semiconductor cooling chips 53 forcibly transfer heat energy between the thermistor ring 51 and the heat-conducting ring 52; a guide ring 54 is provided on the outer end face of the thermistor ring 51; the inner surface of the guide ring 54 has an arc surface that smoothly protrudes towards one side of the semi-finished flat line 3 along the axial direction of the semi-finished flat line 3, and the inner diameter gradually decreases from the end away from the opening at the end of the mold core 2 to the end closer to the opening at the end of the mold core 2; the inner surface of the thermistor ring 51 also has an arc surface that smoothly protrudes towards one side of the semi-finished flat line 3 along the axial direction of the semi-finished flat line 3. The inner diameter of line 3 is gradually reduced from the end away from the opening of the mold core 2 to the end closer to the opening of the mold core 2. The junction of the inner ring of the heat-sensitive ring 51 and the inner ring of the heat-conducting ring 54 forms an obtuse angle. A first annular air outlet slit 55 is attached to the outer end of the air guide ring 54 along its circumference. The first air outlet slit 55 is connected to a first annular air guide cavity 56. One or more first air inlet pipes pressurize and introduce air into the first air guide cavity 56. A comma-shaped air distribution block 57 is arranged along the circumference of the first air guide cavity 56. The air distribution block 57 divides the first air guide cavity 56 into an air pressurization cavity and an air acceleration cavity. The first air outlet slit 55 is connected to the outlet end of the air acceleration cavity.

[0028] Furthermore, a blowing device is respectively provided outside the air guide ring 54 and outside the two short sides of the semi-finished flat wire 3; the blowing device includes a flat annular second air outlet slit 61 extending along the length of the semi-finished flat wire 3; the second air outlet slit 61 is connected to a ring-shaped second air guide cavity 62; one or more second air inlet pipes pressurize and introduce air into the second air guide cavity 62; the second air outlet slit 61 blows out a wind film with a flat and long annular cross-section towards the semi-finished flat wire 3, and drives the air behind the second air outlet slit 61 through the space enclosed by the second air outlet slit 61 and blows it out towards the semi-finished flat wire 3, forming a continuous surface wind pressure.

[0029] Furthermore, the air entering the second air guide cavity 62 is heated; a heating wire mesh 63 is provided behind the second air outlet slit 61 to heat the air that is blown out; the two long sides of the semi-finished flat wire 3 are respectively provided with air guide hoods 64 that gradually change from wide opening to narrow opening; the air guide hoods 64 guide the airflow after the two air blowing devices collide to flow outward.

[0030] Furthermore, the mold sleeve 1 includes a front painting section and a rear paint inlet section, with an inner sleeve 7 fitted inside the paint inlet section; the front end of the inner sleeve 7 is tapered and closely adheres to the surface of the semi-finished flat wire 3; the inner sleeve 7 and the mold sleeve 1 enclose a paint inlet cavity 71; an annular paint inlet piston 72 is sealed and slidably fitted inside the paint inlet cavity 71; the paint inlet piston 72 includes a shovel ring 73 forming an outer ring, a relief ring 74 near the inner ring, and a rear seat ring 75 at the rear; the length of the shovel ring 73 extending forward gradually decreases from the outer ring to the inner ring, forming a shovel head shape; the outer circumferential surface of the shovel ring 73 is sealed and slidably abuts against the inner wall of the mold sleeve 1; The outer circumferential surface of the retraction ring 74 and the inner circumferential surface of the shovel ring 73 are sealed and slide against each other; the inner circumferential surface of the retraction ring 74 and the outer circumferential surface of the inner sleeve 7 are sealed and slide against each other; a spring 76 is provided between the retraction ring 74 and the rear seat ring 75; the shovel ring 73 and the rear seat ring 75 are fixedly connected or integrally formed; multiple linear drive rods 77 are connected to the rear seat ring 75 to drive the paint inlet piston 72 to reciprocate back and forth along the paint inlet cavity 71; one or more paint inlets 78 are provided on the mold sleeve 1 to squeeze and supply paint into the paint inlet cavity 71; the reciprocating motion of the paint inlet piston 72 periodically closes and opens the paint inlet 78.

[0031] A method for coating enameled flat wire, using an enameled flat wire coating mold, includes the following steps: ① The semi-finished flat wire 3 passes through the inner sleeve 7, the front part of the mold sleeve 1, the mold core 2, the heat-sensitive ring 51 and the air guide ring 54 in sequence; the paint part of the mold sleeve 1 and the paint inlet cavity 71 are filled with paint liquid 4; the paint liquid 4 is evenly adhered to the surface of the semi-finished flat wire 3 in the paint part to form a paint film. ② During the painting process, the temperature of the thermistor ring 51 is controlled by the semiconductor cooling chip 53, which causes the thermistor ring 51 to expand and contract, thereby precisely controlling the inner diameter of the thermistor ring 51 and thus controlling the paint film thickness. ③ During the painting process, the first air outlet slit 55 blows out an annular airflow. Under the Coanda effect, the annular airflow adheres to the inner convex surface of the air guide ring 54 and expands outward at the junction with the heat conduction ring 52 at an obtuse angle, thereby forming a pushing air pressure. On the one hand, it shapes the paint film, and on the other hand, it reduces the situation where the paint liquid 4 is squeezed out from the gap. ④ During the painting process, the heated annular air film is squeezed outward from the second air outlet slit 61, and the air heated by the heated wire mesh 63 behind it passes through the space enclosed by the second air outlet slit 61 and moves forward, thereby creating air pressure on the two short sides of the semi-finished flat wire 3, pushing the excess paint liquid 4 to flow towards the long side, avoiding the paint liquid 4 from accumulating at the corner of the semi-finished flat wire 3 and causing the paint film to become "bone-like", and also avoiding the paint film in the central part of the long side of the semi-finished flat wire 3 from becoming thin. ⑤ During the painting process, the linear drive rod 77 pushes the paint inlet piston 72 forward in the paint inlet cavity 71, and the spade ring 73 moves forward and seals the paint inlet 78. During this process, the retraction ring 74 pushes the spring 76 backward to make room and make up for the space occupied by the spade ring 73 during its forward movement. This prevents the paint liquid 4 from being squeezed back to the paint inlet 78 before the spade ring 73 closes the paint inlet 78. It also reduces the excessive pressure on the mold sleeve 1 and the paint liquid 4 in the paint inlet cavity 71, which would cause the paint liquid 4 to be too high. When the paint inlet piston 72 moves forward to its limit, it retracts and returns, allowing the paint inlet 78 to be exposed again to replenish the paint liquid 4. At the same time, a certain negative pressure is generated in the paint inlet cavity 71. This negative pressure causes the paint liquid 4 squeezed into the gap between the mold core 2 and the semi-finished flat wire 3 to shrink back, preventing it from depositing and solidifying at that point.

[0032] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for preparing self-adhesive enameled flat copper wire, characterized in that, Includes the following steps: ① Semi-finished copper billets are drawn to specified specifications and then fed into the copper billets in real time via a wire feeding device; ② Based on the copper conductor size and shape specified by the customer, online precision drawing is performed using a custom-made polycrystalline wire drawing die to produce a square copper conductor with a smooth surface and stable dimensions. ③ The drawn square copper conductor is annealed and softened in a high-temperature non-contact annealing furnace to improve the ductility and stability of various mechanical properties of the copper conductor. ④ Based on the insulation structure requirements and insulation layer thickness requirements specified by the customer, use professional painting molds to perform separate, cyclic painting. ⑤ Use a high-temperature hot air circulating oven to bake and cure the insulating varnish, so that the liquid insulating varnish can fully cross-link under high temperature conditions to form a solid varnish film; ⑥ Use a high-speed turbine fan to blow in a large amount of cold air to quickly and forcibly cool the product, thereby improving the stability of the paint film; ⑦ The surface quality of finished enameled wire products is monitored in real time using high-precision online testing instruments; ⑧ Use the reel specified by the customer to collect and package the finished enameled wire; The enameled flat copper wire prepared by this preparation method includes a copper conductor (31) and a base insulation layer (32) and a self-adhesive insulation layer (33) that are sequentially wrapped around the copper conductor (31) from the inside to the outside; when the self-adhesive insulation layer (33) is wound, adjacent self-adhesive insulation layers (33) can automatically bond to each other after being heated; The painting mold in step ④ includes a hollow mold sleeve (1) and a hollow mold core (2) that can be detachably fitted at the front end of the mold sleeve (1); the inner diameter of the mold sleeve (1) is larger than the size of the semi-finished flat wire (3) to be painted; the semi-finished flat wire (3) passes forward from the rear end of the mold sleeve (1) through the mold sleeve (1) and the mold core (2); the mold sleeve (1) is filled with paint liquid (4); the inner diameter of the mold core (2) gradually decreases along the direction of the semi-finished flat wire (3) until the end opening is slightly larger than the size of the semi-finished flat wire (3), and the shape of the end opening of the mold core (2) is the same as the shape of the semi-finished flat wire (3); the outer surface of the mold sleeve (1) is provided with a groove for mounting on the machine. A thermistor ring (51) is sleeved around the end opening of the mold core (2); a heat-conducting ring (52) is sleeved around the thermistor ring (51) at intervals; a plurality of semiconductor cooling chips (53) are connected between the thermistor ring (51) and the heat-conducting ring (52); the semiconductor cooling chips (53) forcibly transfer heat energy between the thermistor ring (51) and the heat-conducting ring (52); a guide ring (54) is provided on the outer end face of the thermistor ring (51); the inner surface of the guide ring (54) has an arc surface that is smoothly raised towards one side of the semi-finished flat line (3) along the axis of the semi-finished flat line (3), and the inner diameter gradually decreases from the end away from the end opening of the mold core (2) to the end closer to the end opening of the mold core (2); the inner surface of the thermistor ring (51) also has an arc surface that is smoothly raised towards one side of the semi-finished flat line (3) along the axis of the semi-finished flat line (3). The finished flat wire (3) has a smooth, raised arc surface on one side, and its inner diameter gradually decreases from the end away from the opening of the mold core (2) to the end closer to the opening of the mold core (2); the junction of the inner ring of the thermal ring (51) and the inner ring of the heat-conducting ring (54) forms an obtuse angle; the outer end of the air guide ring (54) is attached with a first annular air outlet slit (55) along its circumference; the first air outlet slit (55) is connected to a first annular air guide cavity (56); one or more first air inlet pipes pressurize and introduce air into the first air guide cavity (56); a comma-shaped air distribution block (57) is arranged along the circumference of the first air guide cavity (56); the air distribution block (57) divides the first air guide cavity (56) into an air pressurization cavity and an air acceleration cavity; the first air outlet slit (55) is connected to the outlet end of the air acceleration cavity.

2. The method for preparing a self-adhesive enameled flat copper wire as described in claim 1, characterized in that: The self-adhesive insulating layer (33) is made of semi-aromatic nylon produced by condensation polymerization of aliphatic diamine and aromatic diacid.

3. The method for preparing a self-adhesive enameled flat copper wire as described in claim 1, characterized in that: The basic insulating layer (32) is one or more of the following: modified polyester single coating, polyesterimide single coating, modified polyester composite polyamide-imide coating, polyesterimide composite polyamide-imide coating, polyamide-imide single coating, or polyimide single coating.

4. The method for preparing a self-adhesive enameled flat copper wire as described in claim 1, characterized in that: A blower is provided outside the air guide ring (54) and outside the two short sides of the semi-finished flat wire (3); the blower includes a flat annular second air outlet slit (61) extending along the length of the semi-finished flat wire (3); the second air outlet slit (61) is connected to a ring-shaped second air guide cavity (62); one or more second air inlet pipes pressurize and introduce air into the second air guide cavity (62); the second air outlet slit (61) blows out a wind film with a flat and long annular cross-section in the direction of the semi-finished flat wire (3), and drives the air behind the second air outlet slit (61) through the space enclosed by the second air outlet slit (61) and blows it out in the direction of the semi-finished flat wire (3), forming a continuous surface wind pressure.

5. The method for preparing a self-adhesive enameled flat copper wire as described in claim 4, characterized in that: The air entering the second air guide cavity (62) is heated; a heating wire mesh (63) is provided behind the second air outlet slit (61) to heat the air that is blown out; the two long sides of the semi-finished flat wire (3) are respectively provided with air guide hoods (64) that gradually change from wide opening to narrow opening; the air guide hoods (64) guide the airflow after the two air blowing devices collide to flow outward.

6. The method for preparing a self-adhesive enameled flat copper wire as described in claim 1, characterized in that: The mold sleeve (1) includes a front painting section and a rear paint inlet section. An inner sleeve (7) is fitted inside the paint inlet section. The front end of the inner sleeve (7) is narrowed and closely fits the surface of the semi-finished flat wire (3). The inner sleeve (7) and the mold sleeve (1) enclose a paint inlet cavity (71). An annular paint inlet piston (72) is sealed and slidably fitted inside the paint inlet cavity (71). The paint inlet piston (72) includes a shovel ring (73) forming an outer ring, a retraction ring (74) near the inner ring, and a rear seat ring (75). The length of the shovel ring (73) extending forward gradually decreases from the outer ring to the inner ring, forming a shovel head shape. The outer circumferential surface of the shovel ring (73) is sealed and slidably abuts against the inner wall of the mold sleeve (1). The outer circumferential surface of the retracting ring (74) is sealed and slides against the inner circumferential surface of the shovel body ring (73); the inner circumferential surface of the retracting ring (74) is sealed and slides against the outer circumferential surface of the inner sleeve (7); a spring (76) is provided between the retracting ring (74) and the rear seat ring (75); the shovel body ring (73) and the rear seat ring (75) are fixedly connected or integrally formed; multiple linear drive rods (77) are connected to the rear seat ring (75) to drive the paint inlet piston (72) to reciprocate along the paint inlet cavity (71); one or more paint inlets (78) are provided on the mold sleeve (1) to squeeze and supply paint into the paint inlet cavity (71); the reciprocating motion of the paint inlet piston (72) periodically closes and opens the paint inlet (78).

7. The method for preparing a self-adhesive enameled flat copper wire as described in claim 1, characterized in that, Step ④ specifically includes the following steps: ① The semi-finished flat wire (3) passes through the inner sleeve (7), the front part of the mold sleeve (1), the mold core (2), the heat-sensitive ring (51) and the air guide ring (54) in sequence; the paint part of the mold sleeve (1) and the paint inlet cavity (71) are filled with paint liquid (4); the paint liquid (4) is evenly adhered to the surface of the semi-finished flat wire (3) in the paint part to form a paint film; ② During the painting process, the temperature of the thermistor ring (51) is controlled by the semiconductor cooling chip (53), which causes the thermistor ring (51) to expand and contract, thereby precisely controlling the inner diameter of the thermistor ring (51) and thus controlling the thickness of the paint film. ③ During the painting process, the first air outlet slit (55) blows out an annular airflow. Under the Coanda effect, the annular airflow adheres to the inner convex surface of the air guide ring (54) and expands outward at the junction with the heat conduction ring (52) at an obtuse angle, thereby forming a pushing air pressure. On the one hand, it shapes the paint film, and on the other hand, it reduces the situation where the paint liquid (4) is squeezed out from the gap. ④ During the painting process, the second air outlet slit (61) squeezes out a heated annular air film and drives the air heated by the heated wire mesh (63) behind it to pass through the space enclosed by the second air outlet slit (61) and move forward, thereby creating air pressure on the two short sides of the semi-finished flat wire (3) and pushing the excess paint liquid (4) to flow to the long side, avoiding the paint liquid (4) from accumulating at the corner of the semi-finished flat wire (3) and causing the paint film to be "bone-like", and also avoiding the paint film in the central part of the long side of the semi-finished flat wire (3) from becoming thin; ⑤ During the painting process, the linear drive rod (77) pushes the paint inlet piston (72) forward in the paint inlet chamber (71), and the shovel ring (73) moves forward and seals the paint inlet (78). During this process, the yielding ring (74) pushes the spring (76) backward to make room and make up for the space occupied by the shovel ring (73) during its forward movement, thereby preventing the paint liquid (4) from being squeezed into the paint inlet (78) before the shovel ring (73) seals the paint inlet (78). Backflow is prevented; at the same time, excessive pressure is reduced on the paint liquid (4) in the mold sleeve (1) and the paint inlet cavity (71), which would cause the paint liquid (4) pressure to be too high; when the paint inlet piston (72) advances to the limit and then retracts, the paint inlet (78) is exposed again to replenish the paint liquid (4); at the same time, a certain negative pressure is generated in the paint inlet cavity (71), which causes the paint liquid (4) squeezed into the gap between the mold core (2) and the semi-finished flat wire (3) to shrink back, avoiding deposition and solidification at that place.

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