JP6414739B2 - Conductor softening processing apparatus and conductor softening processing method - Google Patents

Description

  The present invention relates to a conductor softening processing apparatus and a conductor softening processing method.

  For example, a linear conductor is used as a core wire of an enameled wire or a vinyl insulated wire. Such a conductor needs to have flexibility because it is wound to produce a coil, for example. For this reason, in the manufacture of electric wires, in order to ensure the flexibility of the conductor, there is often a step of softening the conductor by heat treatment. However, the conductor may be oxidized by heating in the heat treatment, and the electrical and mechanical performance may be lowered. For example, when the surface of the conductor is oxidized, there may be a disadvantage that the adhesion with a coating film or the like formed on the conductor surface is lowered.

  Therefore, a method is employed in which the atmosphere of the conductor from heating to cooling is made oxygen-free to prevent oxidation. For example, in a softening apparatus that continuously conveys a conductor so as to pass through cooling water stored in a water tank after being heated by a heater, it is tubular so as to surround the conductor from the heating to the water surface of the cooling water. A conductor softening apparatus has been proposed in which a body is disposed and the inside of the tubular body is filled with water vapor of cooling water generated when the conductor is cooled (see JP 2014-1420 A).

JP 2014-1420 A

  In the conductor softening apparatus disclosed in the above publication, the thickness of the oxide film formed on the surface of the conductor can be reduced, but it cannot be said that the oxidation of the conductor is sufficient, and the technology can further suppress the oxidation. Is desired.

  This invention is made | formed based on the above situations, and makes it a subject to provide the conductor softening processing apparatus and the conductor softening processing method which can suppress the oxidation of a conductor.

  A conductor softening treatment apparatus according to an aspect of the present invention made to solve the above-described problem is a conductor softening treatment apparatus that continuously heats and cools a linear conductor, and the conductor is continuous in the axial direction. Feeding mechanism, a heater for heating the conductor conveyed by the feeding mechanism, a cooling tank for storing cooling water for immersing the conductor heated by the heater, and cooling stored in the cooling tank A dissolved oxygen amount adjusting mechanism that maintains a dissolved oxygen amount of water within a predetermined setting range.

  A conductor softening treatment method according to another aspect of the present invention made to solve the above-described problem is a conductor softening treatment method in which a linear conductor is continuously heated and cooled, and the conductor is pivoted on its axis. A step of continuously conveying in the direction, a step of heating the conductor to be conveyed, a step of cooling the heated conductor by immersion in cooling water, and a preset amount of dissolved oxygen in the cooling water Maintaining within the range.

  The conductor softening processing apparatus according to one embodiment of the present invention and the conductor softening processing method according to another embodiment can suppress the oxidation of the conductor.

FIG. 1 is a schematic diagram showing the apparatus configuration of a conductor softening apparatus according to an embodiment of the present invention. FIG. 2 is a graph showing the results of measuring the thickness of the oxide film according to the evaluation test of the present invention.

[Description of Embodiment of the Present Invention]
A conductor softening apparatus according to an aspect of the present invention is a conductor softening apparatus that continuously heats and cools a linear conductor, and includes a feeding mechanism that continuously conveys the conductor in the axial direction thereof, and A heater for heating the conductor conveyed by the feed mechanism, a cooling tank for storing cooling water for immersing the conductor heated by the heater, and a dissolved oxygen amount of the cooling water stored in the cooling tank are predetermined. And a dissolved oxygen amount adjusting mechanism for maintaining within a set range.

  The conductor softening treatment apparatus reduces the amount of oxygen around the conductor cooled from the heated state by immersing the conductor after heating in the cooling water in which the amount of dissolved oxygen in the cooling water is within the above setting range. Can be suppressed. In particular, an oxide film having relatively high adhesion can be formed on the conductor surface by precisely adjusting the amount of oxygen around the conductor cooled from the heated state.

  The dissolved oxygen amount adjusting mechanism includes a supply unit that supplies cooling water to the cooling tank, a dissolved oxygen amount detection unit that measures the dissolved oxygen amount stored in the cooling tank, and the dissolved oxygen amount detection. It is good to have a control part which controls the amount of cooling water supply of the above-mentioned supply part so that the detection value of a part may be maintained in the above-mentioned setting range. As described above, the dissolved oxygen amount adjusting mechanism includes the supply unit, the dissolved oxygen amount detection unit, and the control unit, thereby reliably maintaining the dissolved oxygen amount of the cooling water stored in the cooling tank within the set range. Can do.

  The dissolved oxygen amount adjusting mechanism may further include a deoxygenation unit that reduces the dissolved oxygen amount of the cooling water supplied by the supply unit. Thus, since the dissolved oxygen amount adjusting mechanism has the deoxygenation unit, the dissolved oxygen amount of the cooling water stored in the cooling tank can be reduced and reliably maintained within the set range.

  The cooling tank may have an overflow mechanism that keeps the water level of the cooling water within a predetermined range. As described above, the cooling tank has an overflow mechanism, so that the cooling water stored in the cooling tank can be replaced by replenishing the cooling tank with new cooling water, and the dissolved oxygen amount of the cooling water can be maintained more reliably. be able to.

  It is preferable to further include a tubular member into which a conductor between at least the heater and the water surface of the cooling tank is inserted. Thus, by providing a tubular member, the circumference | surroundings of a conductor can be satisfy | filled with water vapor | steam, and the supply of oxygen to a conductor can be interrupted | blocked more reliably.

  The upper part of the cooling tank may be sealed with a lid. Thus, by sealing the cooling tank with the lid, it is possible to prevent oxygen in the air from being dissolved in the cooling water stored in the cooling tank.

  The upper limit of the setting range is preferably 6 mg / L. Thus, by setting the upper limit of the setting range to 6 mg / L, the effect of suppressing the oxidation of the conductor can be made remarkable by maintaining the dissolved oxygen amount lower than that of normal water.

  A conductor softening treatment method according to another aspect of the present invention is a conductor softening treatment method of continuously heating and cooling a linear conductor, the step of continuously conveying the conductor in its axial direction, A step of heating the conductor being conveyed, a step of cooling the heated conductor by immersion in cooling water, and a step of maintaining the dissolved oxygen content of the cooling water within a predetermined set range.

  The conductor softening treatment method cools the conductor heated with the cooling water whose dissolved oxygen amount is within the above-described setting range, so the amount of oxygen around the conductor cooled from the heated state is reduced to suppress the oxidation of the conductor. be able to.

  Here, the “dissolved oxygen amount” is a value measured in accordance with JIS-K-0101 (1998).

[Details of the embodiment of the present invention]
Hereinafter, embodiments of a conductor softening apparatus according to the present invention will be described in detail with reference to the drawings.

  The conductor softening apparatus of FIG. 1 is a heat treatment apparatus that softens the linear conductor C by continuously heating and cooling. The conductor softening apparatus includes a feeding mechanism 1 that continuously conveys the conductor C in the axial direction, a heater 2 that heats the conductor C that is conveyed by the feeding mechanism 1, and a conductor C that is heated by the heater 2. The cooling tank 3 for storing the cooling water W soaking in, the tubular member 4 through which the conductor C between at least the heater 2 and the water surface of the cooling tank 3 is inserted, and the cooling water W stored in the cooling tank 3 A dissolved oxygen amount adjusting mechanism 5 that maintains a dissolved oxygen amount within a predetermined set range and an air blow 6 that blows air onto the conductor C to remove moisture adhering to the surface are provided.

<Conductor>
The conductor C to be softened in the conductor softening apparatus is not particularly limited. For example, copper wire, copper alloy wire, tin-plated wire, aluminum wire, aluminum alloy wire, steel core aluminum wire, copper fly wire, nickel plating A copper wire, a silver plating copper wire, a copper covering aluminum wire, etc. are mentioned, It is set as a copper wire typically. The average cross-sectional area of the conductor C, and are not particularly limited to, for example, 0.01 mm ² or more 10 mm ² or less. The cross-sectional shape of the conductor C is typically a circular shape, but is not particularly limited, and may be, for example, a rectangular shape.

<Feeding mechanism>
The feed mechanism 1 includes a plurality of guide sheaves (pulleys) 1a, 1b, and 1c around which the conductor C is bridged, and is configured to convey the conductor C in a certain direction indicated by an arrow D. The feed mechanism 1 is provided with an upstream guide sheave 1 a and a downstream guide sheave 1 c disposed above the cooling tank 3, and an intermediate guide sheave 1 b disposed within the cooling tank 3. The conductor C is conveyed so as to pass through the cooling water stored in the tank 3. Preferably, the feed mechanism 1 conveys the conductor C so as to enter the cooling water stored in the cooling tank 3 downward in the vertical direction.

  The speed at which the conductor C is conveyed by the feed mechanism 1 is not particularly limited, but is, for example, 1 m / min to 1000 m / min, typically 5 m / min to 100 m / min.

<Heater>
The heater 2 is a spiral induction heating coil disposed outside a tubular member 4 described later. The induction heating coil generates a high frequency magnetic field when a high frequency current is applied by a high frequency power source (not shown). This high frequency magnetic field induces an eddy current that causes Joule loss in the conductor C. That is, the heater 2 generates an eddy current in the conductor C and causes the conductor C itself to generate heat due to Joule loss.

  By disposing the heater 2 outside the tubular member 4 to be described later, the inner diameter and consequently the internal volume of the tubular member 4 can be reduced, and oxygen around the conductor C can be more effectively eliminated. In addition, by arranging the heater 2 made of an induction heating coil outside the tubular member 4, the induction heating coil can be cooled with a refrigerant or the like, and the output can be easily increased.

  The heating temperature by the heater 2 is selected according to the material of the conductor C and the like, for example, 300 ° C. or more and 500 ° C. or less.

  The length of the heater 2 in the conductor C axial direction is not limited as long as it can sufficiently heat the conductor C, and depends on the coil wire diameter (upper limit of current that can be applied), etc. Is done.

<Cooling tank>
The cooling tank 3 is a water tank that is open at the top for storing the cooling water W. The upper part of the cooling tank 3 is sealed with a lid body 7 that is penetrated by the tubular member 4 and further has a small hole through which the conductor C comes out. Moreover, the cooling tank 3 has the overflow mechanism 8 which maintains the water level of the cooling water W in a predetermined range.

  The capacity of the cooling tank 3 is not particularly limited, and is selected according to the size of the guide sheave 1b. As a material which comprises the cooling tank 3, 1 type, or a combination of multiple types, such as a metal, resin, glass, etc. are used, for example.

(Cooling water)
The cooling water W is stored in the cooling tank 3 so as to immerse the lower end of the tubular member 4.

  As a lower limit value of the set range of the dissolved oxygen amount of the cooling water W in the cooling tank 3, 0.1 mg / L is preferable, and 0.3 mg / L is more preferable. On the other hand, the upper limit of the setting range is preferably 6 mg / L, more preferably 3 mg / L, still more preferably 2 mg / L, and particularly preferably 1 mg / L. In order to prevent the dissolved oxygen content of the cooling water W in the cooling tank 3 from satisfying the lower limit value of the above setting range, a large equipment cost and running cost are required, which may be uneconomical and may be oxidized halfway. There is a possibility that the adhesion of the surface of the conductor C is lowered due to the formation of the film. On the contrary, when the amount of dissolved oxygen in the cooling water W in the cooling tank 3 exceeds the upper limit, the oxidation of the conductor C may not be sufficiently suppressed. That is, the dissolved oxygen amount of the cooling water W in the cooling bath 3 is preferably maintained at a value lower than the dissolved oxygen amount of the water in the open air state, but the smaller the smaller, the more the surface of the conductor C after the softening treatment. It does not mean that adhesion can be improved. Therefore, the adhesiveness of the surface of the conductor C after the softening treatment can be maximized by maintaining the dissolved oxygen amount of the cooling water W in the cooling bath 3 within the above preferable range. If there is no problem in operation and control, the lower limit value of the setting range may be 0 mg / L. In this case, the amount of dissolved oxygen in the cooling water W in the cooling tank 3 only needs to be equal to or less than a preset value (corresponding to the upper limit of the set range). Further, the lower limit value of the setting range may be the same as the upper limit value. That is, the dissolved oxygen amount of the cooling water W in the cooling tank 3 may be adjusted by the dissolved oxygen amount adjusting mechanism 5 described later so that the difference from the set value becomes as small as possible.

  The distance between the heater 2 and the liquid level of the cooling water W in the cooling tank 3 is not particularly limited, and is, for example, 50 mm or more and 200 mm or less, depending on the transport speed of the conductor C.

  The immersion depth of the conductor C in the cooling tank 3, that is, the vertical distance from the liquid surface of the cooling water W to the lower end of the guide sheave 1b in the cooling tank 3, is determined according to the cross-sectional area of the conductor C and the conveying speed. The depth is such that it can be cooled sufficiently.

(Lid)
The lid body 7 restricts the flow of air into and out of the cooling tank 3, but does not have airtightness that makes the pressure in the cooling tank 3 different from the atmospheric pressure. As a material constituting the lid body 7, for example, one kind or a combination of a plurality of kinds such as metal, resin, glass and the like is used.

(Overflow mechanism)
The overflow mechanism 8 causes the cooling water W to overflow so that the water level in the cooling tank 3 does not exceed a certain level. By having this overflow mechanism 8, even if oxygen in the atmosphere is dissolved in the cooling water W in the cooling tank 3 and the dissolved oxygen amount rises, the dissolved oxygen amount from the dissolved oxygen amount adjusting mechanism 5, which will be described later, to the cooling tank 3. By supplying new cooling water W having a small size and preferentially overflowing old cooling water W, the amount of dissolved oxygen in the cooling water W in the cooling tank 3 can be maintained within the set range.

  As the overflow mechanism 8, a pipe or the like that opens to the side wall of the cooling tank 3 is used. As shown in FIG. 1, the overflow mechanism 8 may include a trap 8 a that isolates the space between the internal space of the cooling tank 3 and the atmosphere by the overflowing cooling water W.

<Tubular member>
The tubular member 4 is immersed in the cooling water W stored at the lower end in the cooling bath 3. In the tubular member 4, the conductor C is heated by the heater 2 and then cooled by the cooling water W. When the heated conductor C is immersed in the cooling water W, the cooling water W takes heat of the conductor C and becomes water vapor. The water vapor generated in the tubular member 4 ascends in the tubular member 4 and pushes out air containing oxygen present in the tubular member 4. As a result, the supply of oxygen to the heated conductor C is interrupted, and the oxidation of the conductor C is suppressed.

  The lower limit of the average inner diameter of the tubular member 4 is preferably 1.5 times the maximum diameter of the conductor C, and more preferably twice the maximum diameter of the conductor C. On the other hand, the upper limit of the average inner diameter of the tubular member 4 is preferably 50 mm, and more preferably 30 mm. When the average inner diameter of the tubular member 4 is less than the lower limit, the conductor C may be damaged by contact with the tubular member 4 or the softening treatment may be uneven. On the other hand, when the average inner diameter of the tubular member 4 exceeds the above upper limit, there is a possibility that the exclusion of oxygen by water vapor becomes insufficient.

  As a minimum of average thickness of tubular member 4, 0.5 mm is preferred and 1 mm is more preferred. On the other hand, the upper limit of the average thickness of the tubular member 4 is preferably 10 mm, and more preferably 5 mm. When the average thickness of the tubular member 4 is less than the lower limit, the strength of the tubular member 4 may be insufficient. On the other hand, when the average thickness of the tubular member 4 exceeds the above upper limit, the distance between the heater 2 and the conductor C is increased, and thus the heater 2 may be increased in size.

  The length of the tubular member 4 only needs to surround at least a portion where the conductor C is easily oxidized, that is, a portion in a heated state. That is, at least the lower end of the tubular member 4 is immersed in the cooling water W, and the upper end is disposed at a height higher than the heater 2. Furthermore, it is preferable that the tubular member 4 extends further upward from the upper end of the heater 2. The lower limit of the upward extension length of the tubular member 4 from the upper end of the heater 2 is preferably 10 mm, and more preferably 15 mm. On the other hand, the upper limit of the length of the tubular member 4 extending upward from the upper end of the heater 2 is preferably 500 mm, and more preferably 300 mm. If the upward extension length of the tubular member 4 from the upper end of the heater 2 is less than the lower limit, the amount of oxygen in the atmosphere of the conductor C at the position where the conductor C is in a heated state may not be sufficiently reduced. Conversely, when the length of the tubular member 4 extending upward from the upper end of the heater 2 exceeds the upper limit, the conductor softening device may be unnecessarily enlarged.

  The material constituting the tubular member 4 may be any material that has heat resistance and does not hinder the heating of the conductor C by the heater 2, that is, nonmagnetic and nonconductive, for example, glass, heat resistant resin composition A transparent glass whose inside can be confirmed is particularly preferably used.

<Dissolved oxygen control mechanism>
The dissolved oxygen amount adjusting mechanism 5 includes a supply unit 9 that supplies new cooling water W to the cooling tank 3, a dissolved oxygen amount detection unit 10 that measures the dissolved oxygen amount of the cooling water W stored in the cooling tank 3, A control unit 11 that controls the cooling water supply amount of the supply unit 9 based on the detection value of the dissolved oxygen amount detection unit 10, and a deoxygenation unit 12 that reduces the dissolved oxygen amount of the cooling water W supplied by the supply unit 9; Have

  The dissolved oxygen amount adjusting mechanism 5 has, for example, the detected value of the dissolved oxygen amount of the cooling water W stored in the cooling tank 3 detected by the dissolved oxygen amount detection unit 10 exceeding the upper limit value of the preset setting range. At this time, supply of the new cooling water W in which the amount of dissolved oxygen is reduced by the deoxygenation unit 12 from the supply unit 9 to the cooling tank 3 is started. In addition, the dissolved oxygen amount adjusting mechanism 5 is configured such that when the detected value of the dissolved oxygen amount of the cooling water W stored in the cooling tank 3 detected by the dissolved oxygen amount detection unit 10 is less than the lower limit value of the setting range, The supply of new cooling water W from the supply unit 9 to the cooling tank 3 is stopped. Thereby, the dissolved oxygen amount of the cooling water W stored in the cooling tank 3 is maintained within the set range. In addition, the supply amount of the cooling water W may be adjusted so that the detection value of the dissolved oxygen amount detection unit 10 becomes a representative value within the set range.

(Supply section)
The supply unit 9 is formed from a pipe that supplies new cooling water W to the cooling tank 3, and has an adjustment valve 13 that adjusts the flow rate of the cooling water W supplied to the cooling tank 3.

  The position where the supply unit 9 supplies the cooling water W is preferably a position away from the overflow mechanism 8 of the cooling tank 3. By supplying new cooling water W having a small dissolved oxygen amount from the supply unit 9 by this arrangement, the old cooling water W having an increased dissolved oxygen amount overflows, and as a whole the cooling water W in the cooling tank 3 is dissolved oxygen. The amount can be reduced.

  Furthermore, it is preferable that the supply unit 9 supplies new cooling water W via a pipe that opens into the cooling water W stored in the cooling tank 3. By supplying new cooling water W into the cooling tank 3 in this way, it is possible to prevent oxygen present in the space above the liquid surface from being dissolved into the cooling water W by stirring the liquid surface of the cooling water W.

(Dissolved oxygen detection unit)
The dissolved oxygen amount detection unit 10 detects the dissolved oxygen amount of the cooling water W stored in the cooling bath 3 and transmits it to the control unit 11 as a detection signal. As this dissolved oxygen amount detection part 10, the dissolved oxygen automatic measuring device based on JIS-K-0803 (1995) can be used, for example.

  It is preferable to avoid the position where the dissolved oxygen amount detection unit 10 is located at a position where the dissolved oxygen amount can be smaller than other parts by supplying new cooling water W from the supply unit 9, and suppressing the oxidation of the conductor C. A position where the amount of dissolved oxygen in the cooling water W contributing to the temperature can be measured, that is, the vicinity of the position where the conductor C enters the cooling water W is more preferable.

(Control part)
The control unit 11 adjusts the opening of the adjustment valve 13 of the supply unit 9 so as to maintain the detection value of the dissolved oxygen amount detection unit 10 within a predetermined setting range, thereby supplying the cooling tank 3 of the supply unit 9 to the cooling tank 3. The supply amount of new cooling water W is controlled.

  The control unit 11 can be configured by, for example, a general-purpose computer, a PID controller, a sequencer, or the like. As the control method, for example, PID control, proportional control, on / off control, fuzzy (membership function) control, etc. can be applied.

(Deoxygenation part)
The deoxygenation unit 12 includes, for example, a chemical deoxygenator, a heat deoxygenator, a vacuum deoxygenator, a reverse osmosis membrane deoxygenator, a nitrogen deoxygenator, and the like.

  The chemical deoxygenator removes oxygen by a chemical reaction by adding an oxygen scavenger to make-up water. Examples of the oxygen scavenger include hydrazine, sodium sulfite, natural organic compounds and the like.

  The heating deoxygenator removes dissolved oxygen by heating and boiling the makeup water. Examples of the method for boiling the makeup water include a method of heating the makeup water with a heater and a method of introducing steam into the makeup water.

  The vacuum deoxygenator removes dissolved oxygen by reducing the makeup water. In order to promote deaeration of dissolved oxygen, makeup water may be sprayed.

  The reverse osmosis membrane deoxygenator obtains water having a small dissolved oxygen amount by filtering water using a reverse osmosis membrane that blocks permeation of oxygen.

  The nitrogen deoxygenator brings nitrogen gas into gas-liquid contact with make-up water and moves dissolved oxygen in the make-up water to the nitrogen gas side due to the difference in partial pressure.

  The lower limit of the dissolved oxygen amount of new cooling water W obtained by removing oxygen from the makeup water by the deoxygenation unit 12 as described above is preferably 0.05 mg / L, more preferably 0.1 mg / L. On the other hand, the upper limit of the dissolved oxygen amount of the new cooling water W is preferably 2 mg / L, and more preferably 1 mg / L. In order to make the amount of dissolved oxygen in the new cooling water W less than the lower limit, a large equipment cost and running cost are required, which may be uneconomical. Conversely, when the dissolved oxygen amount of the new cooling water W exceeds the upper limit, the dissolved oxygen amount of the cooling water W in the cooling bath 3 may not be sufficiently reduced.

<Air blow>
The air blow 6 is a non-contact type wiper that blows off water droplets adhering to the surface of the conductor C by blowing air onto the surface of the conductor C coming out of the cooling tank 3. The air blow 6 preferably has a blowing direction and a distance from the lid 7 so that the air blown onto the surface of the conductor C does not easily enter the inside of the cooling tank 3 from the small hole of the lid 7.

[advantage]
The conductor softening apparatus includes the above-described feeding mechanism 1, the heater 2, and the cooling tank 3, and the amount of dissolved oxygen in the cooling water W stored in the cooling tank 3 is within the above-described setting range, so that the heater is heated by the heater. The amount of oxygen supplied to the conductor C can be reduced, and oxidation of the conductor C can be suppressed.

  Moreover, since the said conductor softening processing apparatus is provided with the supply part 9 which has the deoxygenation part 12, the cooling water W which supplies the cooling water 3 with a small enough amount of dissolved oxygen to the cooling tank 3 newly, and stores in the cooling tank 3 The dissolved oxygen amount of W can be more reliably maintained within the above-described setting range.

  Moreover, since the said conductor softening processing apparatus is provided with the dissolved oxygen amount detection part 10 and the control part 11, dissolved oxygen of the cooling water W stored in the cooling tank 3 is not consumed excessively. The amount can be kept low, and the oxidation of the conductor can be reliably suppressed.

  Further, in the conductor softening apparatus, since the cooling tank 3 has the overflow mechanism 8, the cooling water stored in the cooling tank 3 can be easily replaced with a new one, and the dissolved oxygen amount of the cooling water W Can be kept low.

  Moreover, since the said conductor softening processing apparatus is equipped with the tubular member 4, the circumference | surroundings of a conductor are satisfy | filled with water vapor | steam, and it can suppress more reliably the supply of oxygen to a conductor.

  Moreover, since the said conductor softening processing apparatus has the cover body 7 which seals the upper part of the cooling tank 3, it can prevent that the oxygen in air melt | dissolves in the cooling water W stored in the cooling tank 3. FIG.

[Conductor softening method]
The conductor softening treatment method according to one embodiment of the present invention is a conductor softening treatment method in which the linear conductor C is continuously heated and cooled, and can be performed using the conductor softening apparatus of FIG.

  The conductor softening method includes a step of continuously conveying the conductor C in the axial direction, a step of heating the conveyed conductor C, and a step of cooling the heated conductor C by immersion in the cooling water W. And a step of maintaining the dissolved oxygen amount of the cooling water W within a predetermined set range.

<Conveying process>
The said conveyance process can be performed using the feed mechanism 1 of the said conductor softening apparatus of FIG. Accordingly, the transport conditions such as the transport speed are the same as those described for the conductor softening device in FIG.

<Heating process>
The said heating process can be performed using the heater 2 of the said conductor softening apparatus of FIG. Accordingly, the heating conditions are the same as those described for the conductor softening device of FIG.

<Cooling process>
The said conveyance process can be performed by immersing the conductor C in the cooling water W stored in the cooling tank 3 of the said conductor softening apparatus of FIG.

<Maintenance process>
The maintaining step can be performed using the dissolved oxygen amount adjusting mechanism 5 of the conductor softening device of FIG. Accordingly, the conditions and the like of the cooling water W are the same as those described for the conductor softening device in FIG.

[advantage]
The conductor softening treatment method cools the conductor heated with the cooling water having the dissolved oxygen amount within the above-described setting range, so that the amount of oxygen around the conductor can be reduced during heating and cooling to suppress the oxidation of the conductor. it can.

[Insulated wire manufacturing method]
Then, the manufacturing method of the insulated wire using the said conductor soft method is demonstrated. The insulated wire includes a step of softening the conductor by the conductor softening method, a step of applying an insulating paint (varnish) to the surface of the softened conductor, and a step of baking the insulating paint applied to the surface of the conductor by heating. It is manufactured by the method provided.

<Softening treatment process>
The softening treatment step is performed according to the conductor softening treatment method described above.

<Application process>
In the coating step, the conductor C is passed through a coating tank that stores the insulating coating, and the insulating coating adhering to the surface of the conductor C is adjusted to a certain thickness with a die.

  The main component of the insulating paint may be a resin having high insulation and heat resistance, and examples thereof include polyamide, polyimide, polyamideimide, and polyesterimide. The insulating paint can contain a solvent such as N-methyl-2-pyrrolidone or cresol.

  As the above-mentioned die, a known die having an effect that the inner surface is formed in a conical surface, the conductor C is automatically aligned by the wedge film effect, and the film thickness is made constant in the circumferential direction is used.

<Baking process>
In the baking step, the insulating paint is cured by heating the conductor having the surface coated with the insulating paint. When the insulating coating contains a solvent, first, the solvent is volatilized at a temperature lower than the curing temperature of the resin component, and then the temperature is raised to a temperature at which the resin component is cured, thereby forming an insulating coating without bubbles. Can do.

  As the heating method, for example, induction heating that generates heat by electromagnetic induction, radiant heating that heats the insulating paint with the radiant heat of the heater, hot air heating that circulates hot air to heat the insulating paint, and the like can be employed.

[advantage]
Since the insulation coating is formed after the conductor C is softened by the conductor softening treatment method in the above-described method for producing an insulated wire, the conductor C is not oxidized, and an insulated wire having high flexibility and conductivity can be produced. .

[Other Embodiments]
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is not limited to the configuration of the embodiment described above, but is defined by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims. The

  In the conductor softening apparatus, the heater is not limited as long as it can continuously heat the conductor, and may be one that heats the conductor from the outside by flame, heat radiation, or the like. The system heater is more preferable from the viewpoint of the heating time and the heater length and energy efficiency determined thereby. In addition to the induction heating method, the direct heating method heater is an electric heating method in which a current is passed through the conductor between the guide sheaves to generate heat due to Joule loss, and the conductor is looped above the cooling tank. Inductive energization type that energizes the loop portion by electromagnetic induction. As a method of passing an electric current through a conductor for heating, there is a method of applying a voltage between a guide sheave just before the cooling bath and a guide sheave in the cooling bath.

  Moreover, in the said conductor softening processing apparatus, you may arrange | position a heater in a tubular member. Thereby, the material selection possibility of a tubular member can be expanded, and heating efficiency can be improved when using the heater which performs radiation heating.

  In the conductor softening apparatus, the supply unit may be omitted. If the cooling tank is sufficiently large, the dissolved oxygen content of the cooling water in the cooling tank can be kept low for a certain time without supplying new cooling water from the supply unit.

  In the conductor softening apparatus, the overflow mechanism may be omitted. When new cooling water is not excessively supplied, it is not necessary to discharge cooling water from the cooling tank. Even when cooling water is discharged from the cooling tank, a discharge channel is formed in the lower part of the cooling tank, or a suction pump is used. Other means such as drawing out the cooling water may be used.

  In the conductor softening apparatus, a deoxidation unit may be provided in the cooling tank as a dissolved oxygen amount adjustment mechanism that replaces the supply unit. For example, by disposing a device for supplying an oxygen scavenger and a device for supplying nitrogen gas to the cooling bath, the dissolved oxygen content of the cooling water stored in the cooling bath can be kept low. The dissolved oxygen amount adjusting mechanism is not only automatically controlled by the control unit, but may be operated by an operator. Moreover, the amount of dissolved oxygen can be kept low for a certain period of time by preliminarily adding an oxygen scavenger to the cooling tank.

  In the conductor softening apparatus, when the amount of oxygen dissolved from the liquid surface into the cooling water is not so large, the lid of the cooling tank may be omitted.

  Further, in order to reduce the amount of oxygen dissolved from the liquid level into the cooling water, the shape of the cooling tank may be designed so that the area of the liquid level becomes small.

  Further, air blow may be omitted in the conductor softening apparatus.

  EXAMPLES Hereinafter, although this invention is explained in full detail based on an Example, this invention is not interpreted limitedly based on description of this Example.

  A test for softening a hard copper wire as a conductor was performed using an apparatus having a configuration similar to the conductor softening treatment apparatus of FIG. As conditions, the effect of the dissolved oxygen amount of the cooling water on the case where the conductor conveyance speed is 15 m / sec (high linear velocity) and the case where the conductor conveyance speed is 4 m / sec (low linear velocity), respectively. This was confirmed by measuring the average thickness of the oxide film formed on the conductor surface. The average thickness of the oxide film was measured using a voltammetry method.

  As cooling water, water from which impurities have been removed by a reverse osmosis membrane (RO membrane) is used as make-up water, which is directly supplied to the cooling tank bypassing the deoxidation section. The amount of dissolved oxygen in the cooling water in the cooling tank Was about 6 mg / L. Moreover, when the amount of dissolved oxygen in the makeup water was reduced by the deoxygenation section and then supplied to the cooling tank, the amount of dissolved oxygen in the cooling water in the cooling tank was about 0.6 mg / L. Since the operation was not performed for a long time, the increase in dissolved oxygen amount over time was negligible.

  The test results are shown in FIG. In the case of low linear velocity, the average thickness of the oxide film formed when the dissolved oxygen amount of cooling water was about 6 mg / L was 15.5 nm, whereas the dissolved oxygen amount of cooling water was about 0. The average thickness of the oxide film formed when .6 mg / L was 1 nm. In the case of high linear velocity, the average thickness of the oxide film formed when the dissolved oxygen amount of the cooling water was about 6 mg / L was 7 nm, whereas the dissolved oxygen amount of the cooling water was about 0. The average thickness of the oxide film formed when .6 mg / L was 2 nm.

  Thus, it was confirmed that by reducing the dissolved oxygen content of the cooling water, the formation of the oxide film can be significantly suppressed regardless of the transport speed of the conductor.

  The conductor softening apparatus and the conductor softening method according to one embodiment of the present invention can be suitably used for a process of softening a conductor before applying an insulating paint in manufacturing an insulated wire.

DESCRIPTION OF SYMBOLS 1 Feed mechanism 1a, 1b, 1c Guide sheave 2 Heater 3 Cooling tank 4 Tubular member 5 Dissolved oxygen amount adjustment mechanism 6 Air blow 7 Cover body 8 Overflow mechanism 8a Trap 9 Supply part 10 Dissolved oxygen amount detection part 11 Control part 12 Deoxygenation Part 13 Regulating valve C Conductor W Cooling water

Claims (5)

A conductor softening apparatus that continuously heats and cools a linear conductor,
A feeding mechanism for continuously conveying the conductor in the axial direction;
A heater for heating a conductor conveyed by the feeding mechanism;
A cooling tank for storing cooling water for immersing the conductor heated by the heater;
A dissolved oxygen amount adjusting mechanism for maintaining the dissolved oxygen amount of the cooling water stored in the cooling tank within a predetermined setting range ;
The setting range is 0.3 mg / L or more and 2 mg / L or less,
The dissolved oxygen amount adjusting mechanism has a supply unit that supplies cooling water to the cooling tank, and a dissolved oxygen amount detection unit that measures the dissolved oxygen amount stored in the cooling tank,
The cooling tank has an overflow mechanism that keeps the amount of dissolved oxygen in the cooling water in a set range together with the supply unit and keeps the water level of the cooling water in a predetermined range,
The overflow mechanism includes a trap,
The upper part of the cooling tank is sealed with a lid,
The cooling water supply port of the supply unit and the overflow mechanism are arranged apart from each other in the cooling tank,
The detection of dissolved oxygen concentration portion, the conductor softening treatment apparatus the conductor to the cooling water Ru is disposed at a position near the entrance. The dissolved oxygen amount adjusting mechanism, the conductor of claim 1 having a control unit for controlling the cooling water supply amount of the supply unit so as to maintain the detected value of the upper Symbol dissolved oxygen detector within the set range further Softening device.   The conductor softening apparatus according to claim 2, wherein the dissolved oxygen amount adjusting mechanism further includes a deoxygenation unit that reduces the dissolved oxygen amount of cooling water supplied by the supply unit. The conductor softening apparatus according to claim 1 , further comprising a tubular member into which a conductor between at least the heater and the water surface of the cooling tank is inserted. A conductor softening method for continuously heating and cooling a linear conductor,
A step of continuously conveying the conductor in the axial direction;
Heating the conveyed conductor;
Cooling the heated conductor by immersion in cooling water;
Maintaining the amount of dissolved oxygen in the cooling water within a predetermined setting range ,
The setting range is 0.3 mg / L or more and 2 mg / L or less,
The maintenance step is performed by a dissolved oxygen amount adjusting mechanism having a supply unit that supplies the cooling water to the cooling tank and a dissolved oxygen amount detection unit that measures the dissolved oxygen amount stored in the cooling tank,
The cooling tank has an overflow mechanism that keeps the amount of dissolved oxygen in the cooling water in a set range together with the supply unit and keeps the water level of the cooling water in a predetermined range,
The overflow mechanism includes a trap,
The upper part of the cooling tank is sealed with a lid,
The cooling water supply port of the supply unit and the overflow mechanism are arranged apart from each other in the cooling tank,
The detection of dissolved oxygen concentration portion, the conductor softening treatment method the conductor to the cooling water Ru is disposed at a position near the entrance.

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