JP2019136758A - Removal method of tip coating - Google Patents

Abstract

To provide a tip coating removal method capable of removing a tip coating from a coated wire formed by coating a conductive core wire with an insulating coating.SOLUTION: A tip coating removal method includes steps of: forming a groove on a coating along a non-tip side boundary of a tip coating; embrittling the tip coating positioned on the furthermore tip side than the groove; and peeling off the embrittled tip coating from a core wire by spraying air to the groove. Since peeling off from the core wire is carried out by spraying air to the embrittled tip coating, the coating can be peeled off from the core wire in a short time.SELECTED DRAWING: Figure 3

Description

  In order to connect a coated electric wire covered with a conductive core wire with an insulating coating to another component or the like, it is necessary to remove the tip coating and expose the tip core. In this specification, the method of removing a front-end | tip part film | membrane and exposing a front-end | tip part core wire is disclosed. Examples of the coated electric wire here include a magnet wire in which a copper core wire is covered with an enamel coating.

  In the technique of Patent Document 1, laser light is irradiated to the tip coating, bubbles are generated between the tip coating and the tip core wire, the bubbles are expanded, and the tip coating is ruptured. Thereby, a front-end | tip part film is peeled from a front-end | tip part core wire, and a front-end | tip part core wire is exposed.

JP 2010-5562 A

  In the above technique, when the film becomes thick, it takes a long time to heat until the film bursts. In this specification, the technique for peeling a front-end | tip part film from a front-end | tip part core wire in a short time is provided.

  The tip coating removal method disclosed in this specification forms a groove in the coating along the non-tip-side boundary of the tip coating (that is, the boundary between the leading edge where the coating is removed and the non-tip edge where the coating is not removed). The step of embrittlement, the step of embrittlement of the tip coating located on the tip side of the groove, and the step of blowing air to the groove to peel off the embrittled tip coating from the core wire. The groove may have a part of the film remaining on the bottom surface of the groove, or may expose the core wire on the bottom surface of the groove. Further, the step of embrittlement may be a step of heating the tip coating, as long as the tip coating that has become brittle by the force of air blown thereafter is easily peeled off from the core of the tip. .

  According to said structure, since air is sprayed and peeled off from a core wire to the front-end | tip part film | membrane after embrittlement, it is not necessary to heat until a film bursts. For this reason, a film can be peeled from a core wire in a short time. Details and further improvements of the technology disclosed in this specification will be described in the following “Modes for Carrying Out the Invention and Examples”.

The perspective view of the apparatus for implement | achieving the removal method of an Example is shown. An enlarged view of the device is shown. The figure explaining each process of the removal method of an Example is shown.

The features of the embodiment described below will be summarized.
(Feature 1) In the step of forming the groove, the laser is irradiated along the boundary between the range where the film is removed and the range where the film remains.
(Feature 2) In the step of embrittlement, the tip coating is irradiated with a laser having a lower intensity than the laser used in the step of forming the groove.
(Characteristic 3) Using the same apparatus, a step of forming a groove and a step of embrittlement are performed.

  A method for removing the embodiment will be described with reference to the drawings. In the removing method of the embodiment, the coating on the tip of the flat magnet wire 2 (having a rectangular cross section) is peeled off. The magnet wire 2 includes a core wire 3 (see FIG. 3) made of metal (for example, copper) and a coating 4 (see FIG. 3) covering the core wire 3. The coating 4 is an enamel film made of, for example, polyamide, polyamideimide or the like as a main material and is insulative. FIG. 1 is a perspective view of an apparatus 100 for realizing the removal method of the embodiment and a reactor 200 around which a magnet wire 2 to be processed is wound. FIG. 2 is an enlarged view in a range II of FIG. In the following description, the direction in which the distal end portion 2a of the magnet wire 2 extends is referred to as “vertical direction”, and the distal end side is referred to as “upper side”.

  The apparatus 100 shown in FIG. 1 includes four laser irradiators 10 arranged so as to surround the tip 2 a of the magnet wire 2, an air blow device 20, a dust collector 30, and a support base 40 that supports the magnet wire 2. Is provided. The laser irradiator 10 is a device that focuses a laser beam generated from a laser oscillator (not shown) and irradiates the magnet wire 2. The laser irradiator 10 includes a mask 12 that condenses the laser generated from the laser oscillator, a mirror 13 that reflects the laser focused by the mask 12, a focusing lens 14 that focuses the laser reflected by the mirror 13, Is provided. The laser irradiator 10 is movable in the vertical direction. Thereby, the position where a laser is irradiated can be adjusted. The length of the area where the coating is removed can be varied. Further, the laser irradiator 10 is movable in a direction approaching / separating from the magnet wire 2 (that is, a horizontal direction orthogonal to the vertical direction). Thereby, the distance between the laser irradiator 10 and the magnet wire 2 (that is, the distance between the focal point of the focusing lens 14 and the magnet wire 2) can be adjusted. Further, the laser irradiator 10 can adjust the angle in the horizontal direction with the axis in the vertical direction as the rotation axis. Thereby, the irradiation position of the laser on the magnet wire 2 can be adjusted. The laser irradiation position may be adjusted by adjusting the angle of the laser irradiated from the laser oscillator to the laser irradiator 10. The apparatus 100 is not limited to the four laser irradiators 10 and may include three or less or five or more laser irradiators 10.

  The air blow device 20 is a device for blowing air to the tip 2 a of the magnet wire 2. The air blow device 20 includes a supply pipe 22 (not shown in FIG. 2 but present on the left and right sides) to which air is supplied, an insertion hole 24 into which the tip 2 a of the magnet wire 2 is inserted, and a peripheral edge of the insertion hole 24. A plurality of provided outlets 26 are provided. It should be noted that in FIG. 1, the illustration of the outlet 26 and the notation of the reference numerals 24 and 26 are omitted. As shown in FIG. 2, the air discharged from the discharge port 26 is blown toward the distal end portion 2 a of the magnet wire 2 inserted into the insertion hole 24. The opening of the discharge port 26 faces upward, and the inner wall of the discharge port 26 extends obliquely toward the inside. Further, the air blow device 20 is movable in the vertical direction.

  A dust collector 30 shown in FIG. 1 is a device for collecting the coating 4 peeled off from the core wire 3 by the air blown by the air blowing device 20. As shown in FIG. 1, the dust collector 30 is disposed on the downstream side of the air blowing device 20 along the air flow direction.

  With reference to FIG. 3, each step (a) to (f) of the removal method of the embodiment will be described. In the drawings of each step (a) to (f), a cross section of the tip 2a of the magnet wire 2 is shown. The coating 4 covers the entire outer periphery of the core wire 3 of the magnet wire 2, but in the drawings of each step (a) to (f), only the coating 4 on one side in the cross section is shown, and the opposite side. Note that the coating 4 is not shown.

  In the step (a), the laser irradiator 10 is moved to a position where a groove 4c described later is to be formed. It should be noted that the laser irradiator 10 shown in FIG. 3 is drawn to be smaller than the actual size with respect to the tip 2a.

  In the step (b), the coating 4 is irradiated with laser from the laser irradiator 10 to remove the non-tip-side boundary (that is, the coating) of the tip coating 4a covering the tip of the core wire 3 (tip core 3a). A groove 4c is formed along the boundary between the tip portion to be removed and the non-tip portion where the coating is not removed. Specifically, the apparatus 100 performs laser irradiation so that the distance between the laser irradiator 10 and the coating 4 is a distance L that is substantially equal to the focal length (that is, the distance from the principal point of the focusing lens 14 to the focal point). The horizontal position of the vessel 10 is adjusted. Then, the apparatus 100 generates a laser in the laser oscillator and burns out the coating 4. At this time, the apparatus 100 irradiates the laser along the entire outer periphery of the magnet wire 2 by changing the angle of the four laser irradiators 10 in the horizontal direction. Thereby, the groove | channel 4c is formed between the front-end | tip part film | membrane 4a and the non-tip part film | membrane 4b along the whole outer periphery of the magnet wire 2. FIG. In the present embodiment, the core wire 3 is exposed on the bottom surface of the groove 4c. In another example, a part of the film 4 may remain on the bottom surface of the groove 4c.

  As described above, the distance between the laser irradiator 10 and the coating 4 is a distance L substantially equal to the focal length. As a result, the laser is focused in a narrow range, the intensity of the laser (that is, energy passing through the unit area per unit time) is increased, and the coating 4 can be burned out. By burning out the coating 4, a groove 4c having a predetermined width can be formed. Furthermore, the apparatus 100 may adjust the output of the laser oscillator so that the coating 4 is burned out.

  In the step (c), the tip coating 4a is embrittled. Specifically, the apparatus 100 reduces the output of the laser oscillator and reduces the intensity of the laser to such an extent that the coating 4 cannot be burned out. And the apparatus 100 moves the laser irradiation device 10 from the position of the groove | channel 4c to the upper end of the front-end | tip part film 4a, and heats the front-end | tip part film 4a entirely. At this time, the apparatus 100 changes the angle in the horizontal direction of the four laser irradiators 10 and irradiates the entire outer periphery of the tip coating 4 a with laser. As a result, the temperature of the tip coating 4a rises, the tip coating 4a becomes brittle (becomes brittle), and the tip coating 4a is easily peeled off from the core wire 3. In the modification, the apparatus 100 may change the vertical angle of the mirror 13 of the laser irradiator 10 to irradiate the laser from the position of the groove 4c to the upper end of the tip coating 4a.

  In addition, the intensity | strength of the laser in a process (c) should just be adjusted to the intensity | strength which heats the coating film 4, without the coating film 4 being burned out. In other words, the intensity of the laser in step (c) is lower than the intensity of the laser in step (b). For example, in the step (c), the apparatus 100 is configured to position the laser irradiator 10 in the horizontal direction so that the distance between the laser irradiator 10 and the coating 4 is shorter than the distance L in the step (b). May be adjusted. As a result, the laser is focused in a wider range than the range in the focal length, and the intensity of the laser can be lowered. Further, the apparatus 100 may adjust both the distance between the laser irradiator 10 and the coating 4 and the output of the laser oscillator to reduce the laser intensity. Moreover, the apparatus 100 may make the speed which changes the angle in the horizontal direction of the laser irradiator 10 in the step (c) faster than the speed which changes the angle in the horizontal direction of the laser irradiator 10 in the step (b). Thereby, the energy per unit time of the laser irradiated per unit area can be reduced, and the intensity of the laser can be reduced.

  In the step (d), the air blowing device 20 is operated to blow air inside the groove 4c. Thereby, the tip portion coating 4a embrittled in the step (c) is peeled off from the core wire 3 by the force of air to be blown, and is blown upward from the tip. The tip film 4 a that has been blown off is collected by the dust collector 30.

  In the step (e), the remaining coating 4d which is a part of the coating 4 remaining without being peeled off from the core wire 3 in the step (d) is removed. Specifically, the device 100 operates while moving the air blowing device 20 up and down, and blows air over the entire outer periphery (full length) of the core wire 3 a at the tip end portion of the core wire 3. Even if the remaining coating 4d adheres to the tip core wire 3a, the remaining coating 4d is removed from the tip core wire 3a by the force of air. The method of removing the remaining coating 4d is not limited to the method of blowing air, and may be a method of polishing the surface of the core wire 3, for example.

  When the step (e) is completed, as shown in the step (f), the magnet wire 2 in which the leading end core wire 3a of the core wire 3 is exposed is completed.

  The effect of the present embodiment will be described. Reactor 200 is used, for example, in a power conversion device mounted on an electric vehicle. The power conversion device is a device that converts power from a DC power source into power suitable for driving a traveling motor. A large current flows through the reactor 200 in the power converter as the traveling motor increases in output. As the current increases, the coating 4 of the magnet wire 2 becomes thicker. Moreover, the range of the core wire 3 which should be exposed from the front-end | tip part 2a of the magnet wire 2 becomes wide with the low resistance corresponding to a large current. In the conventional removal method, the coating 4 is heated by a laser, and the coating 4 is ruptured to expose the core wire 3. In this removal method, it is necessary to continue heating the coating 4 until the coating 4 is ruptured, and it takes a long time as the thickness of the coating 4 increases, and further, as the range of the core wire 3 to be exposed increases.

  On the other hand, according to the removing method of the present embodiment, air is blown inside the groove 4c between the tip portion coating 4a and the non-tip portion coating 4b, so that the tip coating 4a after embrittlement becomes the core wire 3. It is not necessary to continue heating the coating until it ruptures. In particular, since the step (b) for forming the groove 4c is a step for forming the groove 4c having a predetermined width, the processing time is shorter than the step of heating and rupturing the entire outer periphery of the tip coating 4a. Further, the step (c) of embrittlement of the tip coating 4a is also shorter in processing time than the step of heating and rupturing the entire outer periphery of the tip coating 4a. Further, the step (d) of blowing air into the groove 4c is completed in a short time. Therefore, the processing time from the step (b) to the step (d) is shorter than the processing time of the step of heating and rupturing the entire outer periphery of the tip coating 4a. The processing time can be shortened compared with the conventional removal method, so that the range of the core wire 3 which should be exposed becomes large, so that the thickness of the film 4 becomes thick. According to said Example, the film 4 can be peeled from the core wire 3 for a short time.

  Moreover, the comparative example which heats the front-end | tip part film 4a using the heating means (for example, furnace) different from a laser and embrittles after the process (b) is assumed. On the other hand, according to the configuration of the above-described embodiment, two steps (b) and (b) using one type of means, that is, means for irradiating laser (that is, laser oscillator and laser irradiator 10). c) can be carried out. In addition, in a modification, you may employ | adopt the structure of said comparative example.

  Hereinafter, points to be noted regarding the technology shown in the embodiments will be described. The groove 4c is not limited to a laser, and may be formed using a metal blade. The magnet wire 2 is not limited to a flat magnet wire, and may be a magnet wire having a circular cross section, for example.

  In the above-described embodiment, the laser irradiator 10 includes the focusing lens 14 and focuses the laser generated from the laser oscillator. Instead of this, the laser irradiator 10 may not include a focusing lens, but may include a mirror that reflects the laser focused by the lens in the laser oscillator and a protective glass that protects the mirror.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

2: Magnet wire 2a: Tip 3: Core wire 3a: Tip core 4: Coating 4a: Tip coating 4b: Non-tip coating 4c: Groove 4d: Residual coating 10: Laser irradiator 12: Mask 13: Mirror 14: Focusing lens 20: Air blow device 22: Supply pipe 24: Insertion hole 26: Discharge port 30: Dust collector 40: Support base 100: Device 200: Reactor

Claims (1)

It is a method of removing the tip part coating covering the tip side of the coated wire covered with an insulating coating on a conductive core wire,
Forming a groove in the coating along the non-tip-side boundary of the tip coating;
Embrittlement of the tip coating located on the tip side of the groove;
Blowing air to the groove to peel the tip coating after embrittlement from the core wire;
A method for removing the tip film.

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