JP2019133831A - Manufacturing method of enamel wire, and manufacturing device of enamel wire - Google Patents

Abstract

To provide a manufacturing method of an enamel wire capable of manufacturing even an enamel wire having a conductor with large wire diameter by using a horizontal type galling furnace at high speed and low cost, a manufacturing method of the enamel wire providing a manufacturing device of the enamel wire, and the manufacturing device of the enamel wire.SOLUTION: There is provided a manufacturing method of an enamel wire including a process for applying a thermosetting resin to a conductor having a prescribed cross section shape, galling the thermosetting resin to the conductor by using a horizontal type galling furnace to form a conductor with an insulation coated film, then gradually cooling the conductor with the insulation coated film before applying the thermosetting resin with overlapping on the conductor with the insulation coated film, a process for cooling the conductor with the insulation coated film by a cooling device with water after the process for gradually cooling, and a process for removing water adhered to the conductor with the insulation coated film after the process for cooling.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an enameled wire manufacturing method and an enameled wire manufacturing apparatus.

  There are two types of methods for producing enameled wires used in motors such as automobiles, using a solid baking furnace and using a horizontal baking furnace. As a method for producing enameled wire using a horizontal baking furnace, for example, there is a method described in Patent Document 1.

  In the enameled wire manufacturing method described in Patent Document 1, an annealed copper wire having an outer diameter of 1.00 mm, for example, supplied from a supply device is preheated to a temperature of 80 ° C. to 200 ° C., for example, 150 ° C. A polyesterimide varnish is applied to the outer peripheral surface of the wire in a thickness of 10 to 15 μm, and the varnish applied by introducing the annealed copper wire into a horizontal baking furnace (hereinafter sometimes simply referred to as “baking furnace”) is applied. It has a process of drying and baking.

  Thus, the annealed copper wire in which the insulating film is formed by drying and baking the varnish is led out from the outlet of the baking furnace. The annealed copper wire is heated to 200 ° C. to 350 ° C., and is cooled to about 150 ° C. by an air-cooling device having a blower immediately after being led out.

  In the enameled wire manufacturing method described in Patent Document 1, a combination of the above preheating, varnish coating, drying / baking, and cooling steps constitutes one unit as the coating baking process, and this coating baking By repeating the process a predetermined number of times, an enameled wire having an insulating coating with a predetermined thickness on a conductor made of annealed copper wire is provided.

Japanese Patent Publication No. 61-18287

  However, as in the enameled wire manufacturing method described in Patent Document 1, a varnish coated on a thick conductor having a wire diameter of 0.8 mm or more, for example, a 1.00 mm annealed copper wire is used as a horizontal type. When drying and baking in a baking oven, the thickness of the insulation coating formed around the conductor because the varnish tends to sag under the conductor due to gravity before the varnish applied on the conductor is cured. May become non-uniform.

  On the other hand, it can be considered that by increasing the production speed of the enameled wire, the thickness of the insulating coating is prevented from becoming uneven due to the varnish sagging. However, in an enameled wire manufacturing method with an increased manufacturing speed, when the conductor having a large wire diameter (for example, a conductor having an outer diameter of 0.8 mm or more) is cooled to a predetermined temperature, the temperature of the conductor decreases. Since it becomes difficult, it is necessary to take a long cooling distance.

  On the other hand, in order to manufacture the enameled wire at a low cost, it is indispensable to downsize the enameled wire manufacturing apparatus including the horizontal baking furnace. For this reason, in a method for manufacturing an enameled wire in which the manufacturing speed is increased using a manufacturing apparatus including a horizontal baking furnace, it is desirable to cool the conductor to a predetermined temperature without increasing the cooling distance.

  Therefore, an object of the present invention is to provide an enameled wire manufacturing method and an enameled wire manufacturing apparatus that can manufacture an enameled wire having a thick wire diameter at a high speed and a low cost using a horizontal baking furnace. There is.

  In order to achieve the above-described object, the present invention provides the following enameled wire manufacturing method [1] to [7] and [8] to [13] enameled wire manufacturing apparatus.

[1] After applying a thermosetting resin to a conductor having a predetermined cross-sectional shape and baking the thermosetting resin on the conductor using a horizontal baking furnace to form a conductor with an insulating film, on the conductor with an insulating film Steps of cooling the conductor with an insulating film before the thermosetting resin is applied to the layer, and cooling the conductor with an edge film with a water cooling device after the step of slow cooling And a step of draining water adhering to the edge-coated conductor after the cooling step.
[2] The method for producing an enameled wire according to [1], wherein the step of gradually cooling is performed by slowly cooling the conductor with an insulating film with cold air.
[3] The conductor according to [1] or [2], wherein the conductor has a VD value of 20 or more and 200 or less (= traveling speed of the conductor (m / min) × outer diameter of the conductor (mm)). Enameled wire manufacturing method.
[4] The method for producing an enameled wire according to any one of [1] to [3], wherein the water is pure water or cation exchange water.
[5] The cooling step is any one of the above [1] to [4], which is a step of spraying the water on the conductor with an insulating coating and / or immersing the conductor with an insulating coating in the water. The manufacturing method of enameled wire as described.
[6] The method for producing an enameled wire according to any one of [1] to [5], wherein the draining step is a step of draining water by sucking water adhering to the conductor with the insulating coating.
[7] The method for manufacturing an enameled wire according to any one of [1] to [6], wherein the cooling step is performed before the direction change of the conductor with the insulating coating is performed by a turn pulley.
[8] A horizontal baking furnace for baking the thermosetting resin applied to the conductor to form an insulating film on the conductor, and a slow cooling for gradually cooling the conductor with the insulating film on which the insulating film is formed. An enamel comprising: a device; a cooling device for cooling the slowly cooled conductor with an insulating coating with water; and a draining device for draining water attached to the conductor with an insulating coating cooled with water Wire manufacturing equipment.
[9] The enameled wire manufacturing apparatus according to [8], wherein the slow cooling device includes a radiator cooling air blowing unit and a cooling duct.
[10] The enameled wire manufacturing apparatus according to [9], wherein the radiator cooling air blowing unit is of a water cooling type.
[11] The enameled wire according to any one of [8] to [10], wherein the cooling device includes a water contact portion having a wall surface on which a through path for running the conductor with an insulating coating is formed. manufacturing device.
[12] The draining device adheres to the conductor with insulating coating when the conductor with insulating coating travels through the plurality of conductor passage holes through which the conductor with insulating coating travels, and the conductor passing holes. The apparatus for producing an enameled wire according to any one of [8] to [11], further comprising a suction pump for sucking water.
[13] The enamel according to any one of [8] to [12], wherein the cooling device is installed between the horizontal baking furnace and a turn pulley that changes a direction of the conductor with the insulating coating. Wire manufacturing equipment.

  ADVANTAGE OF THE INVENTION According to this invention, even if it is an enameled wire provided with a conductor with a thick wire diameter, the manufacturing method of an enameled wire and the manufacturing apparatus of an enameled wire which can be manufactured at a high speed and low cost using a horizontal baking furnace are provided. it can.

It is the schematic which shows an example of the manufacturing apparatus of the enamel wire which concerns on embodiment of this invention. It is the schematic which shows an example of the slow cooling apparatus in FIG. It is the schematic which shows an example of the cooling device in FIG. It is the schematic which shows an example of the draining apparatus in FIG. 1, (a) is sectional drawing perpendicular | vertical to a conductor advancing direction, (b) is a perspective view.

[Method for producing enameled wire]
FIG. 1 shows an enameled wire manufacturing method and manufacturing apparatus according to an embodiment of the present invention, and its outline will be described as follows. That is, a thermosetting resin is applied to the conductor 1 supplied from a bobbin or the like by the application unit 14 and baked using a horizontal baking furnace 10 to form an insulating film on the conductor 1, and then superimposed on the insulating film. Before applying the thermosetting resin, the conductor 1 having the insulating film is slowly cooled, and the slowly cooled conductor 1 is cooled with water using a cooling device, and after this cooling, the conductor 1 is attached to the conductor 1. The water thus drained is drained, and the thermosetting resin is applied over the insulating coating. In the present embodiment, the conductor 1 refers only to the conductor 1 before the first application / baking of the insulating paint, and after the first application / baking of the insulating paint, an insulating film is formed on the outer periphery. It refers to the conductor 1a with insulating coating. In the following description, an enameled wire 2 is formed with an insulating film having a desired film thickness.

  FIG. 1 is a schematic diagram illustrating an example of a method and an apparatus for manufacturing an enameled wire 2 according to an embodiment of the present invention, and FIG. 2 is a schematic diagram illustrating an example of a slow cooling apparatus in FIG. FIG. 3 is a schematic diagram illustrating an example of the cooling device in FIG. 1. 4 is a schematic view showing an example of the draining device in FIG. 1, (a) is a cross-sectional view perpendicular to the conductor traveling direction, and (b) is a perspective view.

  The manufacturing method of the enameled wire 2 according to the embodiment of the present invention will be described in detail with reference to FIG. 1. The conductor 1 supplied from a bobbin or the like is guided to the coating unit 14, and an insulating paint is applied to the outer periphery of the conductor 1. Applied. The conductor 1 is, for example, supplied to an annealing furnace (not shown) and annealed. The annealing can be omitted if not necessary.

  The conductor 1a with an insulating coating to which the insulating coating is applied travels in the baking furnace 10 to evaporate the solvent in the insulating coating (that is, dry the insulating coating) and cure the resin in the insulating coating (that is, baking the coating). Drying and baking are performed. The baking furnace 10 may be composed of a combination of a separate evaporation furnace and a curing furnace.

  The method for evaporating the solvent in the insulating paint and curing the resin in the insulating paint in the baking furnace 10 is not particularly limited, and can be performed by heating with hot air or the like.

  As shown in FIG. 1, the conductor 1 a with an insulating coating that has come out from the outlet of the baking furnace 10 (the right end of the baking furnace 10 in FIG. 1) is gradually cooled by the slow cooling device 18, and then cooled by the cooling device 15. After being cooled and drained by the draining device 16, it returns to the upstream turn pulley 13 a via the downstream turn pulley 13 b and the insulating paint is applied by the baking furnace 10, the slow cooling device 18, the cooling device 15, and the draining device 16. Then, evaporation of the solvent in the insulating wire paint, curing of the resin in the insulating paint, slow cooling, cooling, and draining are repeated until a desired film thickness is obtained.

  FIG. 2 shows the slow cooling device 18. The slow cooling by the slow cooling device 18 is performed by air cooling, for example. For example, it is performed by inserting the conductor 1a with an insulating coating derived from the baking furnace 10 into the cooling duct 18d into which the cold air is sent from the radiator cooling air blowing section 18a. The slow cooling is preferably performed so that the temperature of the conductor 1a with the insulating coating derived from the baking furnace 10 is lowered by about 50 to 100 ° C. by the slow cooling.

  The slow cooling device 18 includes a cooling duct 18d through which the conductor 1a with an insulating film led out from the baking furnace 10 is inserted, a radiator cooling blower 18a that sends cold air to the cooling duct 18d, and a blower duct that supplies the cold air to the guide 18c. 18b.

  The radiator cooling air blower 18a is preferably a water-cooled type in order to efficiently and slowly cool the conductor 1a with an insulating coating. For example, in the radiator cooling air blower 18a, a radiator (not shown) is disposed at an air inlet, and water (for example, water of 10 ° C. or lower) is circulated through the radiator by a cooling water circulation device (chiller) (not shown). Has been.

  By performing such slow cooling before cooling by the cooling device 15 described later, it is possible to prevent the conductor 1a with a high-temperature insulating coating derived from the baking furnace 10 from receiving a heat shock due to rapid cooling. .

  Cooling by the cooling device 15 shown in FIG. 3 is performed using water, for example, by spraying water on the conductor 1a with an insulating coating and / or immersing the conductor 1a with an insulating coating in water. In the cooling device 15, it is preferable to cool until it becomes below the glass transition point (Tg) of the thermosetting resin (for example, polyesterimide resin, polyamideimide resin, polyimide resin etc.) which comprises an insulating film.

The cooling device 15 includes a water contact portion 15A configured of a tank in which water is stored, and a pair of opposing wall surfaces disposed separately from each other along the direction in which the conductor 1a with an insulating coating of the water contact portion 15A travels. A water discharge hole 15a (conductor through path) is provided in each of 15C, and when the conductor 1a with an insulating coating passes through the water contact hole 15A through the water discharge hole 15a, the water discharge hole 15a is formed above the water contact part 15A. Water is sprayed onto the conductor 1a with an insulating coating by the _two water jet hoses 15C ₁ and 15C ₂ arranged, and the conductor 1a with an insulating coating is immersed in the water stored in the water contact portion 15A.

Since water flows out from the water discharge hole 15a, the water surface is always replenished with water stored in the water contact portion 15A while spraying water from the water injection hoses 15C ₁ and 15C ₂ onto the conductor 1a with an insulating coating, so that the water surface becomes the water contact portion 15A It is made not to become lower than the conductor 1a with an insulating film that runs on the road. In the present embodiment, the water injection hose 15C ₁ injects water from an obliquely upward upstream side of the traveling direction of the traveling conductor 1a with insulation coating, and the water injection hose 15C ₂ has the insulating coating conductor 1a traveling. However, the present invention is not limited to this, and the water may be injected from one place or from three or more places. In addition, it is possible to inject from various directions such as the injection direction (vertical direction) from directly above the conductor 1a with an insulating coating. Only one of the spraying of water and the immersion in water may be implemented. However, in order to cool in a short time, it is preferable that both are implemented in combination.

  The water is preferably pure water (for example, RO water) or cation exchange water. The water temperature is, for example, preferably 5 ° C. or more and 100 ° C. or less, more preferably 10 ° C. or more and 60 ° C. or less, and further preferably 15 ° C. or more and 40 ° C. or less.

  In the present embodiment, the cooling device 15 can cause a temperature drop of 120 ° C. to 140 ° C.

  The water that flows out from the water discharge hole 15a provided on the wall surface of the water contact portion 15A flows into the water receiving portion 15B that is installed below the water contact portion 15A and to which the support column 15D that supports the water contact portion 15A is fixed. The water is discharged from a water discharge path 15b provided on the bottom wall of the water receiving portion 15B. The water discharged from the water discharge path 15b may be recycled as cooling water. When recycling, the water quality is improved by using a filter or cation exchange resin.

  The step of cooling the conductor with insulation film 1a is preferably performed before the direction change of the conductor with insulation film 1a traveling by the turn pulley 13b is performed. That is, it is preferable that the slow cooling device 18 and the cooling device 15 are installed between the baking furnace 10 and the turn pulley 13b for changing the direction arranged downstream of the baking furnace 10. It is preferable that the slow cooling device 18 and the cooling device 15 are disposed at a position 0.5 to 2 m away from the exit of the baking furnace 10. By setting it as the said structure, when the conductor 1a with an insulating film passes through the turn pulley 13b, it can reduce that the surface of the conductor 1a with an insulating film which contacted the turn pulley 13b will produce a damage | wound.

  The draining of water adhering to the conductor 1a with an insulating coating by the draining device 16 shown in FIGS. 4 (a) and 4 (b) is, for example, by sucking the traveling conductor 1a with an insulating coating through the reduced pressure pipe. Done in

  4A and 4B show the drainer 16. The draining device 16 is a tube having a circular cross section (along the direction in which the conductors 1a with insulating coatings are arranged in parallel) formed by combining a main body upper portion 16A having a semicircular cross section and a main body lower portion 16B having a semicircular cross section. A plurality of conductor passage holes 16C for running the conductor 1a with the insulating coating disposed in the pipe so as to be separated along the direction in which the conductor 1a with the insulating coating runs. A plurality of pipes are formed in parallel along the longitudinal direction of the pipe (the direction in which the conductors 1a with insulating coating are arranged in parallel). Since each conductor passage hole 16C is connected by a passage in a pipe connected to the suction pump 20, the conductor 1a with an insulating coating travels (passes) through each conductor passage hole 16C by operating the suction pump 20. While adhering, the water adhering to the conductor 1a with an insulating film is sucked.

  The draining device 16 is not limited to the shape shown in FIGS. 4 (a) and 4 (b). For example, the drainage device 16 has a rectangular cross section formed by combining a rectangular main body upper section and a rectangular main body lower section. It may be a shaped tube.

  The draining device 16 is not limited to one in which a plurality of conductor passage holes 16C are formed in one tube along the longitudinal direction of the tube. For example, the plurality of draining devices 16 are arranged in parallel. It is also possible to drain each of the conductors with insulating coating 1a to be disposed. Furthermore, the suction amount of the water adhering to the conductor 1a with the insulating coating that runs in the pipe of the draining device 16 may be changed at each conductor passage hole 16C.

  The draining of the water adhering to the conductor 1a with the insulating coating is not limited to the above-described suction method / apparatus, but the method of blowing water through the conductor 1a with the insulating coating into a pipe in which gas (for example, compressed air) is jetted. It can be carried out by an apparatus, a method / apparatus that blows gas (for example, compressed air) from the nozzle onto the conductor 1a with an insulating coating and drains water, or a method / apparatus that evaporates water with hot air or the like to dry. You may use these methods and apparatuses together.

  In addition, when draining only by natural drying during traveling, it is necessary to ensure a long traveling distance especially in the case of a conductor with a large wire diameter, which not only hinders high-speed manufacturing but also reduces site costs and equipment costs. Incurs an increase. Therefore, the draining process / apparatus in the embodiment of the present invention refers to a process capable of draining in a shorter time than draining only by natural drying and an apparatus therefor.

  The drainage of the water adhering to the conductor 1a with the insulating coating is preferably performed after the cooling step and before the thermosetting resin is applied on the insulating coating that has been baked, as shown in FIG. In addition, it is preferable to install a draining device 16 between the cooling device 15 and the turn pulley 13b for changing the direction.

  The insulating film-coated conductor 1a having been baked with an insulating film having a desired thickness (for example, a thickness of 0.020 mm or more and 0.180 mm or less) is wound as an enamel wire 2 on a winder (not shown).

  The material of the conductor 1 used in the present embodiment can be used without any particular limitation, such as copper or copper alloy. Examples of the shape of the conductor 1 include a round wire, a flat wire, and an irregularly shaped wire.

  The insulating paint used in the present embodiment can be used without particular limitation as long as it can be used for the enameled wire 2. Examples of the solvent in the insulating coating include N-methyl-2-pyrrolidone (NMP), cresol, N, N-dimethylacetamide (DMAc), cyclohexanone and the like. Examples of the thermosetting resin in the insulating coating include polyamideimide, polyimide, and polyesterimide.

  According to the enameled wire manufacturing method according to the embodiment of the present invention, a conductor 1 having a large wire diameter (for example, a conductor composed of a round wire having an outer diameter of 0.8 mm or more, a thickness of 1.5 mm or more and a width of 2). Even an enameled wire 2 provided with a conductor made of a flat wire of 0.0 mm or more can be manufactured at a high speed using the horizontal baking furnace 10.

  For example, the traveling speed and the outer diameter of the conductor 1 are set so that the VD value (= the traveling speed (m / min) of the conductor 1 × the outer diameter (mm) of the conductor 1) is in the range of 20 to 200. It is preferable. More preferably, the VD value is set to be in the range of 35 to 140, and more preferably, the VD value is set to be in the range of 40 to 120. When calculating the VD value, in the case of a flat wire, a value converted into a round wire (the diameter of the round wire corresponding to the cross-sectional area of the flat wire) is used as the value of the outer diameter. Similarly, in the case of an irregularly shaped line, a value converted into a round line (the diameter of the round line corresponding to the cross-sectional area of the irregularly shaped line) is used as the value of the outer diameter.

[Enamel wire manufacturing equipment]
An enameled wire manufacturing apparatus according to an embodiment of the present invention includes a horizontal baking furnace 10 for baking a thermosetting resin applied to a conductor 1 to form an insulating film, and a conductor 1a on which an insulating film is formed. A slow cooling device 18 for slow cooling, a cooling device 15 for cooling the slowly cooled conductor 1a with water, and a draining device 16 for draining water adhering to the conductor 1a cooled with water are provided. As a result, a desired effect is obtained.

  The specific configuration of the enameled wire manufacturing apparatus is as shown in FIGS. 1 to 4, and includes the horizontal baking furnace 10, the slow cooling apparatus 18, the cooling apparatus 15, the draining apparatus 16, and the winder 17. .

[Effect of the embodiment of the present invention]
According to the embodiment of the present invention, since there is a step of cooling the conductor with an insulating film using a cooling device with water before applying the thermosetting resin on the insulating film, the conductor with a large wire diameter is An enameled wire manufacturing method and a manufacturing apparatus that can be manufactured at a high speed using a horizontal baking furnace can be provided even if the enameled wire is provided.

  Further, according to the embodiment of the present invention, the conductor with an insulating coating is cooled to a predetermined temperature without increasing the cooling distance by slowly cooling the conductor with an insulating coating with water before cooling with a water. be able to. Therefore, the downsizing of the enameled wire manufacturing apparatus including the horizontal baking furnace can be realized, and the enameled wire can be manufactured at low cost. Furthermore, since the production speed of the enameled wire is increased and the insulating coating can be made difficult to drip after the insulating coating is applied repeatedly, an enameled wire having an insulating coating with a uniform thickness can be obtained.

  Furthermore, according to the manufacturing method according to the embodiment of the present invention, the influence on the working temperature due to the difference in season such as summer and winter can be reduced, and the cooling temperature of the conductor with the insulating coating can be easily made constant, so that the quality varies. The occurrence can be reduced.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible. For example, after the cooling device by water cooling, a cooling device by air cooling of a shorter distance than conventional may be further provided.

1: conductor, 1a: conductor with insulating coating, 2: enameled wire, 10: horizontal baking furnace (baking furnace), 13 (13a, 13b): turn pulley, 14: coating section, 15: cooling device, 15A: water contact section , 15B: water receiving portion, 15C: _walls, 15C 1, 15C _2: water discharge hose, 15D: posts, 15a: water discharge hole, 15b: water discharge path, 16: draining device, 16A, 16B: upper body, 16C : Conductor passage hole, 18 Gradual cooling device, 18a: Radiator cooling air blowing part, 18b: Air blowing duct, 18c: Guide part, 18d: Cooling duct, 20: Suction pump

Claims (13)

A thermosetting resin is applied to a conductor having a predetermined cross-sectional shape, and the thermosetting resin is baked onto the conductor using a horizontal baking furnace to form a conductor with an insulating film, and then superimposed on the conductor with an insulating film. Before applying the thermosetting resin, slowly cooling the conductor with an insulating coating;
After the step of slowly cooling, the step of cooling the edge-coated conductor using a cooling device with water,
A method for producing an enameled wire, comprising: after the cooling step, draining off water adhering to the conductor with the edge coating. The step of slowly cooling is performed by slowly cooling the conductor with an insulating film with cold air.
The method for producing an enameled wire according to claim 1. The conductor has a VD value of 20 or more and 200 or less (= running speed of the conductor (m / min) × outer diameter of the conductor (mm)).
The method for producing an enameled wire according to claim 1 or 2. The water is pure water or cation exchange water.
The manufacturing method of the enameled wire as described in any one of Claims 1-3. The step of cooling is a step of spraying the water on the conductor with an insulating coating and / or immersing the conductor with an insulating coating in the water.
The manufacturing method of the enameled wire as described in any one of Claims 1-4. The step of draining is a step of draining by sucking water adhering to the conductor with an insulating coating,
The manufacturing method of the enameled wire as described in any one of Claims 1-5. The step of cooling is performed before the direction change of the conductor with the insulating coating is performed by a turn pulley.
The manufacturing method of the enameled wire as described in any one of Claims 1-6. A horizontal baking furnace for baking the thermosetting resin applied to the conductor to form an insulating film on the conductor;
A slow cooling device for slow cooling the conductor with an insulating coating on which the insulating coating is formed;
A cooling device for cooling the annealed conductor with an insulating coating with water;
An enameled wire manufacturing apparatus comprising: a draining device for draining water attached to the conductor with an insulating coating cooled by the water. The slow cooling device includes a radiator cooling air blowing unit and a cooling duct.
The enameled wire manufacturing apparatus according to claim 8. The radiator cooling air blower is a water-cooled type.
The enameled wire manufacturing apparatus according to claim 9. The cooling device includes a water contact portion having a wall surface on which a through path for running the conductor with an insulating coating is formed.
The manufacturing apparatus of the enameled wire as described in any one of Claims 8-10. The draining device includes a plurality of conductor passage holes for running the conductor with an insulating coating, and water attached to the conductor with an insulating coating when the conductor with the insulating coating is running through the plurality of conductor passage holes. With a suction pump for aspirating,
The manufacturing apparatus of the enameled wire as described in any one of Claims 8-11. The cooling device is installed between the horizontal baking furnace and a turn pulley that changes the direction of the conductor with the insulating coating,
The enameled wire manufacturing apparatus according to any one of claims 8 to 12.

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