A system and method for stripping enameled wire

Abstract

This invention discloses a system and method for stripping enameled wire. The stripping system includes a stripping furnace, a displacement lifting platform, a positioning fixture, and a protective cover. The displacement lifting platform is located above and behind the stripping furnace. The positioning fixture is mounted on the worktable of the displacement lifting platform and is equipped with an enameled wire clamping fixture. The stripping furnace is equipped with a temperature control device. The protective cover is located outside the stripping furnace. The stripping furnace is equipped with a post-processing unit and a lighting unit. The method includes the following steps: S1, solution preparation; S2, temperature setting and heat preservation; S3, positioning and stripping; S4, post-processing. This invention uses sodium hydroxide with a purity greater than 99% to chemically react with the enamel layer to remove the enamel, without damaging the copper wire itself, thus maintaining the original mechanical strength and conductivity of the lead wire. The liquid solution stripping process of this invention is stable, without splashing of powder or liquid such as BT-122 stripping powder, avoiding damage to other intact parts of the enameled wire by splashes, and improving the product qualification rate.

Description

Technical Field

[0001] This invention belongs to the field of electronic component manufacturing technology, specifically relating to a method and system for removing enamel coating from the ends of enameled copper round wires and enameled copper flat wires used in components such as planar transformers and inductors. Background Technology

[0002] In the manufacturing process of key electronic components such as transformers and inductors, an indispensable step is the treatment of both ends of enameled wire. For reliable subsequent electrical soldering or mechanical connections, the insulating varnish layer within a specific length of the wire end must be thoroughly and cleanly removed. Traditional varnish removal processes used in the industry mainly rely on two types of technologies: one is physical grinding, such as using high-speed rotating grinding wheels or special grinding rollers; the other is chemical varnish removal, typically represented by using a solution prepared from a special varnish-removing powder such as BT-122.

[0003] Physical grinding relies on the high-intensity mechanical friction between an abrasive tool and the surface of the enameled wire to scrape off the enamel layer. While this method is direct, it is highly susceptible to causing irreversible physical damage to the copper wire itself, which acts as the conductor. During the grinding process, not only is the insulating enamel removed, but a layer of the copper material itself is also ground away, resulting in significant copper loss (see reference). Figure 1 The thickness loss can even reach 0.2 mm. This damage severely weakens the mechanical strength and current-carrying cross-sectional area of ​​critical connection parts of the lead wire, thereby directly affecting the long-term operational reliability, electrical performance stability, and service life of the final product.

[0004] Chemical paint stripping methods, exemplified by BT-122 paint stripper powder, dissolve the paint layer through the corrosive properties of the solution. However, this method commonly suffers from the troublesome problem of solution splattering in practice. The splattered corrosive droplets or powder can contaminate the intact paint on areas that do not require treatment (see reference). Figure 2 This can cause unexpected damage to the paint layer, resulting in uncontrollable quality defects that directly lead to a low overall product qualification rate and a high rework rate.

[0005] Furthermore, Chinese patent CN110246680B discloses a device for bending and stripping the enamel coating at the end of a transformer enameled wire winding assembly. This device uses cylinders C and D to push the wire out, facilitating bending. However, this operation can easily cause the enameled wire to pull out or break, thus damaging the wire.

[0006] In summary, whether it is physical grinding, chemical paint stripping, or the currently commonly used solutions, they all face many inherent drawbacks and challenges, such as low production efficiency, difficulty in accurately controlling process parameters, poor quality consistency, safety risks to operators (such as mechanical injuries and chemical burns), and potential environmental pollution (such as chemical waste treatment). Summary of the Invention

[0007] The purpose of this invention is to provide a system and method for removing the enamel coating from enameled wires, addressing the technical problems described in the background art.

[0008] The technical solution of the present invention: A stripping system for enameled wire includes a stripping furnace, a displacement lifting platform, a positioning fixture, and a protective cover. The displacement lifting platform is located above and behind the stripping furnace. The positioning fixture is mounted on the worktable of the displacement lifting platform and is equipped with an enameled wire clamping fixture. The stripping furnace is equipped with a temperature control device. The protective cover is located on the outside of the stripping furnace. The stripping furnace is equipped with a post-processing unit and a lighting unit.

[0009] The protective cover has a window on the right side and an opening on the top of the protective cover. The opening is connected to an exhaust unit, which is connected to the operating area of ​​the paint stripping oven.

[0010] The displacement lifting platform is equipped with an adjusting handwheel, a locking device, and a scale.

[0011] The temperature control device is a temperature controller, and the paint stripping furnace is made of a material resistant to sodium hydroxide corrosion.

[0012] A method based on an enameled wire stripping system includes the following steps: S1. Solution preparation: Add solid sodium hydroxide to the paint stripping furnace, heat until it melts into a liquid state, and perform aging treatment at a set temperature to obtain a stable paint stripping solution; S2. Temperature setting and heat preservation: According to the diameter of the round wire / thickness of the flat wire D of the enameled wire to be treated, heat the paint stripping solution to the corresponding preset temperature range and keep it at that temperature. S3. Positioning and stripping: Fix the end of the enameled wire to be stripped with a positioning fixture, control its movement with a displacement lifting platform, so that the end is accurately immersed in the stripping solution, and control the immersion time according to the diameter of the round wire / thickness of the flat wire D. S4. Post-treatment: The enameled wire ends that have been stripped of paint are then subjected to neutralization, deionized water cleaning, and drying in sequence.

[0013] In step S1, the solid sodium hydroxide is caustic soda flakes with a purity greater than 99%.

[0014] In step S1, the aging process is carried out at a temperature of 380°C for 8 hours.

[0015] In step S2, the preset temperature is controlled in stages according to the diameter of the round wire / thickness D of the flat wire: When 0.06mm≤D<0.1mm, the preset temperature is 320℃±10℃; When 0.1mm≤D<0.25mm, the preset temperature is 340℃±10℃; When 0.25mm≤D<0.8mm, the preset temperature is 360℃±10℃; When D≥0.8mm, the preset temperature is 380℃±10℃.

[0016] In step S2, the heat preservation time shall not be less than 15 minutes.

[0017] In step S3, the immersion time is controlled in stages according to the diameter of the round wire / thickness D of the flat wire: When 0.06mm≤D<0.1mm, the immersion time is 8 seconds to 12 seconds; When 0.1mm≤D<0.25mm, the immersion time is 8 seconds to 18 seconds; When 0.25mm≤D<0.8mm, the immersion time is 8 seconds to 20 seconds; When D≥0.8mm, the immersion time is 8 seconds to 25 seconds.

[0018] The beneficial effects of this invention are: This invention uses sodium hydroxide with a purity greater than 99% to chemically react with the varnish layer to remove the varnish, rather than physical grinding. This method does not damage the copper wire itself and maintains the original mechanical strength and conductivity of the lead wire.

[0019] The liquid solution of this invention provides a smooth paint removal process without splashing of powder or liquid such as BT-122 paint remover, thus avoiding damage to the intact paint coating of other parts of the enameled wire and improving the product qualification rate.

[0020] This invention achieves rapid paint removal by precisely controlling temperature and time, resulting in a smooth, clean surface that exposes the pure copper's metallic luster and ensures stable quality.

[0021] This invention features a matching exhaust unit and protective cover, which effectively controls the operating environment, reduces safety risks, and ensures thorough post-treatment neutralization and cleaning without any harmful chemical residues.

[0022] This invention, through graded parameter settings, is applicable to the deenamelting of various specifications of enameled wire with a round wire diameter / flat wire thickness D of 0.06mm or more, and has strong versatility. Attached Figure Description

[0023] Figure 1 This is a photograph of copper damage caused by physical grinding rollers removing paint; Figure 2 This is a real photo showing paint damage caused by paint peeling powder splashing. Figure 3 This is a schematic diagram of the structure of the present invention; Figure 4 This is a schematic diagram of the enameled wire stripping system of the present invention without the protective cover installed; Figure 5This is a schematic diagram showing the positional relationship between the positioning fixture and the enameled wire clamping fixture of the present invention; Figure 6 This is a schematic diagram of the paint stripping furnace of the present invention; Figure 7 This is a schematic diagram of the displacement lifting platform of the present invention; Figure 8 This is a rendering of the enameled wire product after processing by the method of this invention.

[0024] Attached reference numerals: 1-Paint stripping furnace, 2-Displacement lifting platform, 3-Positioning fixture, 4-Post-processing unit, 5-Exhaust unit, 6-Lighting unit, 7-Protective cover, 8-Window opening, 9-Opening, 10-Enameled wire clamping fixture, 11-Workbench surface, 12-Locking device, 13-Scale, 14-Adjusting handwheel, 15-Temperature control device. Detailed Implementation

[0025] refer to Figures 3-8 A wire stripping system includes a stripping furnace 1, a displacement lifting platform 2, a positioning fixture 3, and a protective cover 7. The displacement lifting platform 2 is located above the rear of the stripping furnace 1. The positioning fixture 3 is mounted on the worktable 11 of the displacement lifting platform 2. The positioning fixture 3 is equipped with a wire clamping fixture 10. The stripping furnace 1 is equipped with a temperature control device 15. The protective cover 7 is located on the outside of the stripping furnace 1. The stripping furnace 1 is equipped with a post-processing unit 4 and a lighting unit 6.

[0026] The paint stripping furnace 1 is made of a sodium hydroxide corrosion resistant material and is used to hold and heat molten sodium hydroxide solution. In this invention, the sodium hydroxide corrosion resistant material is made of 316 stainless steel, which has the properties of corrosion resistance, high temperature resistance, and mechanical strength.

[0027] The paint stripping furnace 1 is equipped with a temperature control device 15, which is a temperature controller. The temperature controller is mainly used to control the heating of the resistance plate at the bottom of the paint stripping furnace 1, that is, to control the heating and temperature rise of the paint stripping furnace 1 in this invention, so as to heat the solid sodium hydroxide and achieve the purpose of melting the solid sodium hydroxide. In this invention, the displacement lifting platform 2 is a Z-axis precision displacement lifting platform, which is located above and behind the paint stripping furnace 1. Its worktable is used to mount the positioning fixture 3 and can precisely control the vertical movement distance and positioning accuracy.

[0028] Positioning fixture 3 is installed on the worktable 11 of the Z-axis precision displacement lifting table 2, and the enameled wire clamping fixture 10 is placed on it. The enameled wire clamping fixture 10 is used to clamp the enameled wire to facilitate better handling of the enameled wire.

[0029] In this invention, the post-processing unit 4 includes a container for neutralization, a container for cleaning, and supporting facilities.

[0030] The lighting unit 6 is used for work lighting. In this invention, the lighting unit 6 is an LED lamp or a lighting lamp.

[0031] The protective cover 7 has a window 8 on the right side and an opening 9 on the top of the protective cover. The opening 9 is connected to an exhaust unit 5, which is connected to the operating area of ​​the paint stripping oven 1.

[0032] The protective cover 7 mainly serves a protective function to prevent splashing and injury; the window 8 facilitates the replacement of the cable; the opening 9 allows for connection to the exhaust unit 5.

[0033] In this invention, the exhaust unit 5 is an exhaust fan that is connected to the opening 9 through a pipe and is connected to the paint stripping furnace 1 and the operating area, and is used to discharge volatiles.

[0034] The displacement lifting platform 2 is equipped with an adjusting handwheel 14, a locking device 12, and a scale 13.

[0035] The adjusting handwheel 14 is used to adjust the lifting height of the displacement lifting platform 2. The scale 13 is mainly for easy viewing of the adjusted lifting height for accurate positioning; the locking device 12 is mainly for locking the displacement lifting platform 2 after the height adjustment is fixed for subsequent operations.

[0036] In this invention, the locking device 12 consists of a locking screw hole and a matching locking screw on the side of the displacement lifting platform 2.

[0037] A method based on an enameled wire stripping system includes the following steps: S1. Solution preparation: Add solid sodium hydroxide to paint stripping furnace 1, heat until it melts into a liquid state, and perform aging treatment at a set temperature to obtain a stable paint stripping solution; Solid sodium hydroxide is caustic soda flakes with a purity greater than 99%.

[0038] The aging process is carried out at a temperature of 380℃ for 8 hours.

[0039] S2. Temperature setting and heat preservation: According to the diameter of the round wire / thickness of the flat wire D of the enameled wire to be treated, heat the paint stripping solution to the corresponding preset temperature range and keep it at that temperature. The preset temperature is controlled in stages based on the diameter of the round wire / thickness D of the flat wire: When 0.06mm≤D<0.1mm, the preset temperature is 320℃±10℃; When 0.1mm≤D<0.25mm, the preset temperature is 340℃±10℃; When 0.25mm≤D<0.8mm, the preset temperature is 360℃±10℃; When D≥0.8mm, the preset temperature is 380℃±10℃.

[0040] Keep warm for at least 15 minutes.

[0041] S3. Positioning and stripping: Fix the end of the enameled wire to be stripped using the positioning fixture 3, and control its movement using the displacement lifting platform 2 to precisely immerse the end in the stripping solution. Control the immersion time according to the diameter of the round wire / thickness of the flat wire D. Immersion time is controlled in stages based on the diameter of the round wire / thickness D of the flat wire: When 0.06mm≤D<0.1mm, the immersion time is 8 seconds to 12 seconds; When 0.1mm≤D<0.25mm, the immersion time is 8 seconds to 18 seconds; When 0.25mm≤D<0.8mm, the immersion time is 8 seconds to 20 seconds; When D≥0.8mm, the immersion time is 8 seconds to 25 seconds.

[0042] In steps S2 and S3 of this invention, the temperature and immersion time are precisely controlled according to the diameter of the enameled wire, which can achieve the best paint removal effect without damaging the copper substrate.

[0043] S4. Post-treatment: The enameled wire ends that have been stripped of paint are then subjected to neutralization, deionized water cleaning, and drying in sequence.

[0044] In this invention, the neutralization treatment involves soaking and shaking the affected area in an acidic neutralizing solution, followed by rinsing with deionized water at least four times.

[0045] The invention will be illustrated below through a set of implementation examples: Example 1: A method for The process of removing the enamel coating from 0.25mm enameled wire leads.

[0046] First, system preparation is carried out. The system mainly includes a paint stripping furnace 1 (made of 316 stainless steel, with a temperature control device), a displacement lifting table 2 (i.e., a Z-axis precision displacement lifting table, with a scale 13 and a locking device 12), and a positioning fixture 3 ( Figure 4 The oven 1 is equipped with a neutralization and cleaning tank (post-processing unit 4) and an exhaust unit 5, and a protective cover 7.

[0047] Implementation steps: S1. Prepare the paint stripping solution: Add solid sodium hydroxide (caustic soda flakes) with a purity >99% to paint stripping furnace 1, and heat to 380℃ until it is completely melted into a liquid state. Add caustic soda flakes to the maximum liquid level line, and then continue heating at 380℃ for 8 hours to carry out "aging treatment" to stabilize the solution state.

[0048] S2. Setting the process temperature: The enameled wire diameter D=0.25mm is being processed, falling within the range of 0.25mm≤D<0.8mm. Based on the preset parameters, the temperature of the paint stripping solution is set and stabilized at 360±10℃. After reaching this temperature, it is maintained for at least 15 minutes to ensure uniform temperature within the furnace.

[0049] S3. Positioning and Enamel Removal: Straighten the enameled wire lead of the transformer coil to be treated and fix it on the positioning fixture 3. Then place the positioning fixture 3 on the worktable 11 of the displacement lifting platform 2. Adjust the height of the displacement lifting platform 2 according to the enamel removal length required by the drawing so that the end of the lead just touches the surface of the solution. Then start the lifting platform to immerse the end of the lead into the solution. The immersion depth is the enamel removal length, and the immersion time is controlled between 8 and 20 seconds (12 seconds is selected in this example).

[0050] S4. Post-processing: After the time is up, the displacement lifting platform 2 is raised. Immediately immerse the stripped lead end in a container containing BT-122 red water (acidic neutralizing solution), with the immersion depth exceeding the stripped length by 5mm, and shake back and forth at least 4 times. Then, immerse the lead end in deionized water, and shake and clean it at least 4 times. Finally, wipe it with a lint-free cloth dampened with cleaning agent, rinse it clean with deionized water, and transfer it to drying or the next process.

[0051] Throughout the operation, exhaust unit 5 runs continuously. Operators must wear protective gloves and clothing.

[0052] like Figure 8 As shown, after treatment by the method of this invention, the enamel layer on the lead end of the enameled wire is completely removed, the copper wire surface is bright and undamaged, and the enamel coating on other parts of the lead is intact, fully achieving the goal of "no copper damage and no splash damage". Calculations show that compared with traditional methods, the overall processing efficiency of this invention can be improved by more than 50%.

Claims

1. A system for stripping enamel from enameled wire, characterized in that... The system includes a paint stripping furnace (1), a displacement lifting platform (2), a positioning fixture (3), and a protective cover (7). The displacement lifting platform (2) is located above the rear of the paint stripping furnace (1). The positioning fixture (3) is mounted on the worktable (11) of the displacement lifting platform (2). The positioning fixture (3) is equipped with an enameled wire clamping fixture (10). The paint stripping furnace (1) is equipped with a temperature control device (15). The protective cover (7) is located outside the paint stripping furnace (1). The paint stripping furnace (1) is equipped with a post-processing unit (4) and a lighting unit (6).

2. The enameled wire stripping system according to claim 1, characterized in that: The protective cover (7) has a window (8) on the right side and an opening (9) on the top of the protective cover. The opening (9) is connected to an exhaust unit (5), which is connected to the operating area of ​​the paint stripping oven (1).

3. The enameled wire stripping system according to claim 1, characterized in that: The displacement lifting platform (2) is equipped with an adjusting handwheel (14), a locking device (12), and a scale (13).

4. The enameled wire stripping system according to claim 1, characterized in that: The temperature control device (15) is a temperature controller, and the paint stripping furnace (1) is made of a material resistant to sodium hydroxide corrosion.

5. A method for stripping enameled wire based on the enameled wire stripping system according to any one of claims 1-4, characterized in that: Includes the following steps: S1. Solution preparation: Add solid sodium hydroxide to the paint stripping furnace (1), heat until it melts into a liquid state, and perform aging treatment at a set temperature to obtain a stable paint stripping solution; S2. Temperature setting and heat preservation: According to the diameter of the round wire / thickness of the flat wire D of the enameled wire to be treated, heat the paint stripping solution to the corresponding preset temperature range and keep it at that temperature. S3, Positioning and Removal: Fix the end of the enameled wire to be removed by the positioning fixture (3), and control its movement by the displacement lifting platform (2) so that the end is precisely immersed in the paint removal solution. The immersion time is controlled according to the diameter of the round wire / thickness of the flat wire D. S4. Post-treatment: The enameled wire ends that have been stripped of paint are then subjected to neutralization, deionized water cleaning, and drying in sequence.

6. The method for stripping enamel from enameled wire according to claim 5, characterized in that: In step S1, the solid sodium hydroxide is caustic soda flakes with a purity greater than 99%.

7. The method for stripping enamel from enameled wire according to claim 5, characterized in that: In step S1, the aging process is carried out at a temperature of 380°C for 8 hours.

8. The method for stripping enameled wire according to claim 5, characterized in that: In step S2, the preset temperature is controlled in stages according to the diameter of the round wire / thickness D of the flat wire: When 0.06mm≤D<0.1mm, the preset temperature is 320℃±10℃; When 0.1mm≤D<0.25mm, the preset temperature is 340℃±10℃; When 0.25mm≤D<0.8mm, the preset temperature is 360℃±10℃; When D≥0.8mm, the preset temperature is 380℃±10℃.

9. The method for stripping enamel from enameled wire according to claim 5, characterized in that: In step S2, the heat preservation time shall not be less than 15 minutes.

10. The method for stripping enameled wire according to claim 5, characterized in that: In step S3, the immersion time is controlled in stages according to the diameter of the round wire / thickness D of the flat wire: When 0.06mm≤D<0.1mm, the immersion time is 8 seconds to 12 seconds; When 0.1mm≤D<0.25mm, the immersion time is 8 seconds to 18 seconds; When 0.25mm≤D<0.8mm, the immersion time is 8 seconds to 20 seconds; When D≥0.8mm, the immersion time is 8 seconds to 25 seconds.

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