JP2015080281A - Assembled conductor and motor - Google Patents

Abstract

Provided is a method of manufacturing a collective conducting wire in which conductor wires are more reliably insulated from each other. A method of manufacturing a collective conducting wire (20), which includes a coating step (S1), a converging step (S2), and a plastic working step (S3). In the coating step (S1), a lubricant to which sulfate is added is applied to the plurality of conductor wires (1, 2). In the focusing step (S2), a plurality of conductor wires are bundled to form a conductor bundle (1, 2). Further, in the plastic working step (S3), the conductor bundle is plastically processed to form the collective conductor (20). [Selection] Figure 2

Description

  The present invention relates to a method for manufacturing a collective conducting wire and a motor.

  There is a collective conductor in which a plurality of conductor wires are bundled. In such a collective conducting wire, an insulating film may be formed between the bundled conductor wires. The conductor wires are insulated from each other by an insulating film. It is preferable to use such a collective conducting wire as a coil because eddy loss is low.

  For example, in the manufacturing method disclosed in Patent Document 1, a plurality of conductor wires covered with an insulating film are bundled, and then the plurality of bundled conductor wires are press-molded to produce a collective conducting wire.

JP 2002-027693 A

  However, in the manufacturing method disclosed in Patent Document 1, when the press molding is performed, the insulating film may be broken and the conductor wires may be electrically connected.

  The present invention has been made against the background described above, and an object of the present invention is to provide a method of manufacturing a collective conducting wire in which conductor wires are more reliably insulated.

The manufacturing method of the collective conducting wire according to the present invention is as follows.
An application step of applying a lubricant to which a sulfate ester is added to a plurality of conductor wires (for example, strands);
A bundling step of bundling the plurality of conductor wires to form a wire bundle (for example, a bundled aggregate conductor);
A plastic working step of plastically processing the wire bundle to form an assembly conductor (for example, an assembly conductor).

  According to such a structure, the assembly conducting wire in which the conductor wires are more reliably insulated is manufactured.

In addition, after the plastic working step, an oxide film containing CuO may be formed on the surface of the conductor wire. In addition, after the coating step, a product containing CuSO ₄ may be formed on the surface of the conductor wire. Moreover, it is good also as a heating process which heats the said assembly conducting wire after the said plastic working process. The concentration of the sulfate ester in the lubricant may be 1.0 to 2.4 mol / l or less. The oxide film may have a thickness of 130 nm to 300 nm.

  On the other hand, the motor according to the present invention is a motor having a coil made of the collective conducting wire manufactured by the above-described collective conducting wire manufacturing method.

  According to such a configuration, a motor having a coil with low vortex loss can be obtained.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the assembly conducting wire from which conductor wires are insulated more reliably can be provided.

FIG. 3 is a cross-sectional view of the collective conducting wire according to the first embodiment. 3 is a flowchart showing a manufacturing method according to the first exemplary embodiment. FIG. 3 is a schematic diagram illustrating an example of a manufacturing method according to the first embodiment. It is a graph which shows the electrical resistance with respect to an oxide film thickness. It is a graph which shows a vortex loss reduction rate.

Embodiment 1 FIG.
The collective conducting wire obtained by the manufacturing method according to the first embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view of the collective conducting wire according to the first embodiment.

  As shown in FIG. 1, the collective conducting wire 20 is a linear body including one central strand 1 and a plurality of peripheral strands 2. In the cross section of the assembly conducting wire 20, the peripheral strand 2 is arranged so as to surround the central strand 1. An insulating film 3 is formed between the central strand 1 and the peripheral strand 2. In the cross section of the assembly conducting wire 20, the insulating film 3 is a film having a length L and a thickness t. The length L is the same as the peripheral length of the central strand 1 and a part of the peripheral length of the peripheral strand 2. Further, the thickness t is not necessarily constant, and may be within a predetermined range. The insulating film 3 electrically insulates the central strand 1 and the peripheral strand 2 and also electrically insulates adjacent peripheral strands 2 from each other. When the collective conducting wire 20 is used as a coil, a coil with low vortex loss can be obtained.

  Next, the manufacturing method according to the first embodiment will be described with reference to FIG. FIG. 2 is a flowchart illustrating the manufacturing method according to the first embodiment.

First, a lubricant is applied to a plurality of strands (application step S1). For workability, a plurality of strands may be aligned in one direction using a roller or the like. Here, as the element wire, a conductor line made of a material containing at least copper can be used. An example of such a material is a conductor wire made of copper or a copper alloy. Here, as an example of the lubricant used, a lubricant used for wire drawing by adding a sulfate ester (R—O—SO ₂ —O—R) can be given. Examples of the sulfate ester include dimethyl sulfate.

Here, when the lubricant is applied to the strands, the sulfate ester reacts with copper (Cu) contained in the strands. Then, a product containing copper sulfate (CuSO ₄ ) is formed on the surface of the strand.

  Subsequently, a plurality of strands are bundled to form a conductor bundle (focusing step S2). In order to adjust the gap between the strands, the arrangement of the strands may be changed as appropriate.

Subsequently, the conductive wire bundle is plastically processed to form a collective conductive wire (plastic processing step S3). Examples of the plastic working include alignment, twisting, and pressing. Here, the assembly conductor may generate heat due to plastic working. Due to this heat generation, a product containing CuSO ₄ may cause a chemical reaction represented by the following chemical reaction formula 1.
CuSO ₄ → CuO + SO ₃ (chemical reaction formula 1)
When this chemical reaction occurs, an oxide film containing CuO is formed on the surface of the strand.

  Finally, the assembly conductor is heated in a heating furnace as necessary (heating step S4). For example, a high-frequency heating device can be used instead of the heating furnace. Here, the chemical reaction represented by the chemical reaction formula 1 is further promoted, and an oxide film containing CuO is more reliably formed on the surface of the strand. In addition, the thickness of the oxide film containing CuO increases.

  Next, an example of the manufacturing method according to the first embodiment will be described with reference to FIG. FIG. 3 is a schematic diagram illustrating an example of the manufacturing method according to the first embodiment. This example is a manufacturing method in which the assembly conductor 202 is continuously manufactured from the conductor wire group 198 using the manufacturing apparatus 140. In FIG. 3, the conductor wire group 198 schematically represents a state in which the conductor wires 109 are arranged in the direction from the back to the front of the page.

  The wire feeder 141 sends the conductor wire group 198 to the first rolling roll 142. As shown in the schematic diagram 158, the conductor wire 109 is a linear body having a circular cross section. The conductor wire 109 is a part of the conductor wire group 198 that forms the peripheral strand 110.

  The first rolling roll 142 receives the conductor wire group 198 from the wire feeder 141 and forms the peripheral wire 110 from a part of the conductor wire group 198 as shown in a schematic diagram 159. The first rolling roll 142 plastically deforms the conductor wire 109. The cross-sectional shape of the peripheral strand 110 is, for example, a trapezoidal shape.

  The first rolling roll 142 sends a strand group 199 composed of the peripheral strands 110 and the central strand 130 to the speed adjusting guide roller 143. The strand group 199 schematically represents a state in which the strands are arranged in the direction from the back to the front of the page.

  The speed adjusting guide roller 143 receives the strand group 199 from the first rolling roll 142 and removes the deflection of the peripheral strand 110 generated in the strand processing step. The speed adjustment guide roller 143 sends the strand group 199 to the direction adjustment roller 144.

  The direction adjusting roller 144 receives the strand group 199 from the speed adjusting guide roller 143. The orientation adjusting roller 144 develops each strand of the strand group 199 and creates a positional relationship in which the peripheral strand 110 surrounds the central strand 130.

  In addition, the orientation adjusting roller 144 adjusts the position and orientation of the peripheral strand 110 so that the inner peripheral surface of the peripheral strand 110 faces each side of the central strand 130. The orientation adjusting roller 144 sends the strand group 199 to the clamp 145.

  Until the conductor wire group 198 is sent from the wire feeder 141 to the clamp 145, the lubricant is applied to at least one of the conductor wire group 198 or the wire group 199. That is, in this example, any process until the conductor wire group 198 is sent from the strand feeder 141 to the clamp 145 corresponds to the coating process S1. In particular, it is preferable to apply a lubricant to the strand group 199 because the lubricant is likely to remain sufficiently on the surfaces of the peripheral strand 110 and the central strand 130.

  Subsequently, the clamp 145 receives the strand group 199 from the orientation adjustment roller 144. The clamp 145 aligns the strand group 199 and arranges the peripheral strand 110 around the central strand 130 to form an aligned assembly conductor, that is, an aligned assembly conductor 200. In addition, the clamp 145 forms the aligned assembly conductor 200 so that the inner peripheral surface of the peripheral strand 110 faces each side of the outer surface of the central strand 130. In this example, the process in which the clamp 145 forms the aligned assembly conductor 200 corresponds to the focusing process S2.

  The clamp 145 applies a predetermined pressure to the aligned collective conductor 200 toward the center of the aligned collective conductor 200. For this reason, as shown in the schematic diagram 160, the central strand 130, the peripheral strand 110, and the peripheral strands 110 are close to each other in the cross section 190 of the aligned assembly conductor 200. The clamp 145 sends the aligned assembly conductor 200 to the rotating machine 146.

  The rotating machine 146 rotates in a predetermined rotation direction 152. In FIG. 3, the rotation direction 152 has a direction for imparting a right-handed twist to the aligned assembly conductor 200. As the twisting process, the rotating machine 146 twists the aligned assembly conductor 200 around the central strand 130 to form the twisted assembly conductor 201.

  As shown in the schematic diagram 161, the aligned aggregate conductor 200 is an aggregate conductor in which a central strand 130 and a peripheral strand 110 having a predetermined shape are aligned. For this reason, the rotating machine 146 can form the cross section 191 in which the substantially circular shape of the cross section 190 is maintained. The rotating machine 146 sends the twist assembly conductor 201 to the clamp 147.

  The clamp 147 receives the twist assembly conductor 201 from the rotating machine 146. The clamp 147 applies a predetermined pressure to the twisted conductor 201 toward the center of the twisted conductor 201. For this reason, the center strand 130, the peripheral strand 110, and the peripheral strands 110 that are loosely adhered in the twisting process are brought into close contact again. The clamp 147 sends the twist assembly conductor 201 to the speed adjustment guide roller 148.

  The speed adjusting guide roller 148 receives the twisted aggregate conductor 201 from the clamp 147 and removes the deflection of the twisted aggregate conductor 201 generated in the twisting process. The speed adjusting guide roller 148 sends the twisted aggregate conductor 201 to the second rolling roll 151.

  The second rolling roll 151 receives the twist assembly conductor 201 from the speed adjusting guide roller 148. As the plastic working step S3, the second rolling roll 151 applies a substantially planar pressure from the longitudinal direction in the drawing when the twisted aggregate conductor 201 has a substantially flat shape.

  As shown in the schematic diagram 162, the second rolling roll 151 gives a lateral wall surface 194 to the upper and lower ends of the cross section 192 of the assembly conducting wire 202 in the drawing. The second rolling roll 151 sends the collective conducting wire 202 to the heating furnace 150.

  The heating furnace 150 receives the assembly conductor 202 from the second rolling roll 151 and heats it as the heating step S4. The heating furnace 150 may send the collective conducting wire 202 to the coil manufacturing process as necessary.

  In the first embodiment, the aligned collective conductor 200 is twisted to form the twisted collective conductor 201 by passing through the orientation adjusting roller 144, the clamp 145, the rotating machine 146, and the clamp 147. A twisted aggregate conductor may be formed. The left and right reverse twist assembly conductors are, for example, a twisted portion twisted so as to draw a spiral with the central strand 130 as an axis, and a reverse twisted portion twisted in a direction opposite to the twisted direction of the twisted portion. And a twisted assembly conductor. Note that the left-right reverse twist assembly conductor may have a non-twist portion that is parallel to the axis of the central strand 130 between the twist portion and the reverse twist portion.

  Here, the manufacturing method of the left-right reverse twist assembly conductor will be described. After completion of the focusing step S <b> 2 of the first embodiment, the clamp 145 passes the aligned assembly conductor 200 through the rotating machine 146 and further to the clamp 147. Subsequently, the clamp 145 and the clamp 147 simultaneously clamp the collective conductor 200 and fix the axis of the aligned collective conductor 200. Further, while the clamp 145 and the clamp 147 clamp the aligned collective conductor 200, the rotating machine 146 rotates in a predetermined rotation direction 152 and twists the aligned collective conductor 200. Then, a left-right reverse twist assembly conductor is formed. Here, the left and right reverse twist assembly conductor has a twist portion and a reverse twist portion with the rotating machine 146 as a boundary.

Examination of oxide film thickness.
Next, a preferable range of the thickness t of the oxide film formed between the conductor wires in the collective conducting wire will be described with reference to FIG. FIG. 4 is a graph showing the electric resistance with respect to the oxide film thickness.

  As shown in FIG. 4, when the thickness of the oxide film exceeds 130 nm, the electrical resistance of the oxide film can exceed 0.3Ω. It has been found by experiments so far that the vortex loss of the coil decreases when the electrical resistance between the conductor wires exceeds 0.3Ω in the collective conducting wire. In other words, the oxide film thickness necessary for reducing the vortex loss of the coil is at least 130 nm.

  By the way, when the thickness of the oxide film exceeds 300 nm, the oxide film may not be adhered to the conductor wire and may be peeled off. That is, the thickness of the oxide film necessary for ensuring the adhesion strength with the conductor wire is 300 nm or less.

  From the above, it is preferable that the thickness of the oxide film is 130 nm or more and 300 nm or less because both reduction of vortex loss and securing of adhesion strength can be achieved.

Examination of sulfuric acid ester concentration in lubricant.
Next, the preferable range of the concentration of the sulfate ester in the lubricant will be described with reference to FIG. 1 again.

Here, regarding the number of moles n _{E of} sulfate ester contained in the lubricant per unit length per strand and the number of moles n _C per unit length of CuO in the oxide film formed between the strands Each will stand. Subsequently, the concentration _CE of the sulfate ester in the lubricant is obtained by utilizing the fact that these mole numbers are equal.

The number of moles n _E [mol] of the sulfate ester is determined by the following formula 1.
_{n E = C E × V lu} ... ( Equation 1)
C _E [mol / l]: Concentration of sulfate ester in the lubricant _Vlu [mm ³ ]: Volume per unit length in which the lubricant can exist between the strands

Subsequently, a volume _Vlu per unit length in which the lubricant can exist between the strands is obtained by the following formula 2.
_{V lu = L × t s ×} 1 [mm 3] ... ( Equation 2)
L [mm]: The length of the space between the strands to which the oxide film is to be applied (see FIG. 1)
t _s [mm]: gap between strands

Here, the gap _{t s} between the wires is about 0.01mm. Therefore, Formula 2 can be transformed into Formula 3.
_Vlu = _Lx10 < ^-5 > [mol / mm < ³ >]
= L × 10 ⁻⁸ [mol / L] (Formula 3)
Furthermore, from the above formulas 1 and 3, the number of moles n _E [mol] of the sulfate ester is expressed by the following formula 4.
n _E = C _E × L × 10 ⁻⁸ [mol] (Formula 4)

Next, the number of moles n _C per unit length of CuO in the oxide film formed between the strands is formulated. The number of moles n _C per unit length of CuO in the oxide film formed between the strands can be obtained by the following formula 5.
n _C = V _fl × ρ / M _C (Formula 5)
V _fl : oxide film volume per unit length of the assembly conductor ρ: density of CuO M _C: molar mass of CuO

Subsequently, the oxide film volume V _fl [mm ³ ] per unit length of the collective conducting wire is expressed by the following Equation 6.
V _fl = L × t (Formula 6)
t: thickness of oxide film (see FIG. 1) [mm]

Furthermore, the density ρ [g / mm ³ ] of CuO is 6.31 × 10 ⁻³ , and the molar mass M _C [g / mol] of CuO is 79.545. Then, the number of moles n _C of the copper oxide CuO is represented by the following formula 7.
n _C = L × t × ρ / M _C
n _C = L × t × (6.31 × 10 ⁻³ ) /79.545
n _C = L × t × (7.93 × 10 ⁻⁵ ) (Formula 7)

Here, since the number of moles n _E and the number of moles n _C are equal, the following Expression 8 is established from Expression 3 and Expression 6 described above.
C _E × L × 10 ⁻⁸ = L × t × (7.93 × 10 ⁻⁵⁾ ) (Formula 8)
When L and the like are deleted from Expression 7, the following Expression 9 is obtained.
C _E = t × 7.93 × 10 ³ (Formula 9)

As described above, the preferable range of the thickness t of the oxide film is 130 nm or more and 300 nm or less. The upper and lower limit values of the preferable range of the thickness t of the oxide film are substituted into the above-described Expression 7. Then, the sulfuric acid ester concentration _CE in the lubricant is determined to be 1.0 to 2.4 mol / l. From the above, it is preferable that the concentration _CE of the sulfate ester in the lubricant is 1.0 to 2.4 mol / l because it is possible to ensure that the thickness t of the oxide film is 130 nm or more and 300 nm or less. .

  As described above, according to the first embodiment, the insulating film having a certain range of thickness is formed on the surface of the conductor wire, and the conductor wires are reliably separated from each other by the insulating film. That is, a collective conducting wire in which conductor wires are more reliably insulated can be manufactured.

  By the way, manufacture of the assembly lead wire which press-molds a plurality of bare copper wires and then forms an oxide film between the lead wires by infiltrating the liquid for forming the oxide film between the copper wires and heating it. There is a way. In such a manufacturing method, the liquid for forming the oxide film cannot be infiltrated between the copper wires, and the oxide film may not be formed. On the other hand, according to Embodiment 1 described above, the lubricant added with sulfate as a liquid for forming the oxide film can be reliably applied to the conductor wires, and the conductor wires are more reliably insulated from each other. Collective conductors can be manufactured.

  In addition, in Embodiment 1, although heating process S4 was implemented, you may abbreviate | omit heating process S4 as needed. For example, in the plastic processing step S3, when the processing heat is generated in the strand and the oxide film containing CuO is sufficiently formed, the heating step S4 may be omitted.

Eddy loss experiment.
Next, a test in which an assembly conductor is manufactured as an example using the manufacturing method according to the first embodiment and the eddy loss of the manufactured assembly conductor is measured will be described with reference to FIG. FIG. 5 is a graph showing the eddy loss reduction rate. In addition, in order to compare with an Example, the eddy loss was measured also about the comparative example. The comparative example is a collective conductor manufactured by the same manufacturing method as the manufacturing method according to the first embodiment except that no lubricant is used.

  As shown in FIG. 5, in the embodiment, the eddy loss reduction rate exceeds 80%. Here, 80% is a calculated value of the eddy loss reduction rate when the conductor wires are separated from each other by an insulating film having a predetermined thickness and are reliably insulated. That is, 80% is an ideal value of the eddy loss reduction rate. In the example, it is considered that the conductor wires included in the collective conducting wire are reliably insulated by the insulating film having a predetermined thickness.

  On the other hand, in the comparative example, the eddy loss reduction rate was about 40%. The eddy loss reduction rate of the comparative example is far below the ideal reduction rate of 80%. That is, in the comparative example, it is considered that the conductors included in the collective conductor are not insulated by the insulating film, are in direct contact with each other, and are electrically connected to each other.

Application example.
A coil can be formed using the collective conducting wire obtained by the manufacturing method according to the first embodiment. For this reason, this embodiment is suitable for the following applications.

  The motor can include a coil made of a collective conductor manufactured by the above manufacturing method. Since such a coil has a small vortex loss, the motor exhibits a performance equivalent to that of the conventional one with a small coil.

  Moreover, an automobile becomes light weight by providing such a motor while maintaining the conventional performance. It is preferable from the viewpoint of weight reduction that an automobile includes a drive unit having such a motor. Such a motor is particularly suitable for hybrid cars and plug-in hybrid cars.

S1 coating process, S2 focusing process, S3 plastic working process,
S4 heating process,
1, 2, 109 conductor wire, 198 conductor wire group, 199 strand group, 200 aligned aggregate conductor, 20, 201, 202 aggregate conductor (aggregate conductor)

Claims (7)

An application step of applying a lubricant to which a sulfate ester is added to a plurality of conductor wires;
A bundling step of bundling the plurality of conductor wires to form a wire bundle;
A plastic working step of plastically processing the wire bundle to form a collective wire; and
The manufacturing method of the assembly conducting wire containing.   2. The method of manufacturing a collective conducting wire according to claim 1, wherein an oxide film containing CuO is formed on the surface of the conductor wire after the plastic working step. The method for producing a collective conducting wire according to claim 1, wherein a product containing CuSO ₄ is formed on a surface of the conductor wire after the coating step. After the plastic working step, the method further includes a step of heating the assembly conductor.
The manufacturing method of the assembly conducting wire as described in any one of Claims 1-3 characterized by the above-mentioned. The concentration of the sulfate ester in the lubricant is 1.0 to 2.4 mol / l.
The manufacturing method of the assembly conducting wire as described in any one of Claims 1-4 characterized by the above-mentioned. The oxide film has a thickness of 130 nm to 300 nm.
The manufacturing method of the assembly conducting wire according to any one of claims 2 to 5.   The motor which has a coil which consists of an assembly conducting wire manufactured by the manufacturing method according to any one of claims 1 to 6.

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