JP2008290107A - Die for working electric wire, and special shape electric wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the damage of an insulation coating layer of an electric wire when a round electric wire is deformed into a special shape electric wire by means of a die. <P>SOLUTION: A round cross section electric wire 20 having an insulation coating layer 20b formed on the surface of a conductive body 20a is deformed into a special shape electric wire 20A having a polygonal cross section, and is drawn out by means of a die 10 for working an electric wire. In the die 10, the cross sectional shape of a working hole 13 for continuously passing the electric wire in the axial direction is a circular shape at the inlet port 13a for inserting the round electric wire into the die, and is a polygonal shape at the outlet port 13b for drawing out the wire from the die as the special shape electric wire 20A, and continuously varies from the circular shape to the polygonal shape with the distance in the axial direction from the inlet port 13a toward the outlet port 13b. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a die for processing an electric wire and a deformed electric wire processed by the die, and more specifically, an electric wire having a circular cross section is drawn through the die to obtain a deformed electric wire having a polygonal cross section. At the time of processing, the corners of the polygonal cross section are processed into the same shape as the die shape without damaging the insulating coating layer covered with the conductor of the electric wire.

Conventionally, an electric wire is wound around a stator of a motor to form a coil, and the electric wire forming the coil is usually a round electric wire having a circular cross-section with an insulation coating.
However, when a multi-layer coil is formed using a round electric wire, there is a problem that a gap is generated between adjacent electric wires between radial layers, and the space factor of the electric wire is reduced. The space factor refers to the ratio of the electric wire area in the cross section of the coil arrangement space, and a decrease in the space factor causes deterioration in motor efficiency and motor output.
For this reason, it has been proposed to form a coil using a deformed electric wire having a hexagonal shape or a quadrangular polygonal cross section.
If the hexagonal or quadrangular deformed electric wires are used to form a multi-layer with aligned winding, a part of the electric wires of the layer adjacent in the radial direction can be just fitted into the gap between the electric wires adjacent in the axial direction. The space between them can be reduced to improve the coil space factor.
At this time, if the cross-sectional shape of the hexagonal or quadrangular shaped electric wire has a rounded corner (vertical angle) and is rounded, the winding space factor decreases and the electric wire is adjacent when it generates heat. Since the contact area between the electric wires is small and the heat conduction path is narrow and disadvantageous for heat dissipation, it is required that corners be formed.

As a method for manufacturing the irregular shaped electric wire having a polygonal cross section, a method of pulling a round electric wire through a die provided with a through hole having a polygonal cross section, or passing a round electric wire between rolling rolls provided with a groove having a polygonal cross section, etc. The method is used.
For example, in Japanese Patent Application Laid-Open No. 6-106226 (Patent Document 1), as shown in FIG. 9, a lubricating oil is supplied to a round electric wire 100 serving as a bus bar at an inlet into a processing hole 101 a having a circular cross section of a first die 101. Then, the wire is passed and drawn, and then deformed through a second die 102 having a deformed hole 102a different from the cross-sectional shape of the round electric wire 100, and is drawn out as a deformed electric wire 100A having a triangular cross section or the like.

  In Patent Document 1, two types of dies, the first die 101 and the second die 102, are used, the periphery of the wire is sealed between the dies, and the lubricating oil supplied at the inlet of the first die 101 is moved by moving the wire. It draws into the sealed space between the inner peripheral surface between each die and the outer peripheral surface of the wire, and the pressure of the lubricating oil is gradually increased to cause forced circulation in the second die 102, thereby being loaded on the electric wire. The processing burden is reduced.

JP-A-6-106226

  As described above, in Patent Document 1, a wire formed of a round electric wire is drawn by drawing the wire diameter with the first tie 101, and then the round electric wire is deformed into a cross-sectional shape with one second die 102. . For example, as described in paragraph 0017, the shape of the deformed hole 102a of the second die 102 for deformation is a square cross-section processed hole, so that the outer peripheral surface of the round wire is the second die. At the stage of contact with the inner peripheral surface of the irregularly shaped hole, the insulating coating layer on the outer periphery of the round electric wire is suddenly subjected to deformation pressure on the inner peripheral surface of the irregularly shaped hole. Therefore, even if the lubricating oil is supplied between the outer peripheral surface of the round electric wire and the inner peripheral surface of the deformed hole, the edge coating layer on the outer periphery of the round electric wire may be damaged.

In addition, in order to deform a round wire into a deformed cross-section, the cross-sectional center of the round wire and the cross-sectional center of the deformed hole should be aligned with the axis of the deformed hole so that the deformation pressure is applied evenly around the round wire. preferable. However, if a round electric wire is inserted into the processing hole of the second die and the outer periphery of the round electric wire comes into contact with the inner peripheral surface of the processing hole of the square cross section and receives a sudden deformation pressure, the center of the cross section of the round electric wire has a deformed hole. Since it is eccentric from the center of the cross section and the deformation pressure is not evenly applied to the circular insulating coating layer but is applied to the circular insulating coating layer, damage is likely to occur in the insulating coating layer portion that has received a strong deformation pressure.
Furthermore, if the round wire is pulled out of the die without the deformation pressure being evenly applied to the round wire due to eccentricity or the like, the round wire does not deform along the inner surface of the machining hole of the second die, and the corner of the square section of the deformed wire (Vertical angle) is greatly rounded, resulting in a deformed electric wire with a large radius at the corner of the cross section. Further, when the corners of the cross section have large radiuses, the insulating coating layer at the corners becomes thinner than the insulating coating layer at the side portion of the cross-sectional shape.

  The present invention has been made in view of the above problems, and when processing a round electric wire into a deformed electric wire having a polygonal cross section with a die, it is possible to reliably prevent damage to the insulating coating layer covered with the conductor of the electric wire, The object is to reliably prevent the corners from being formed in the same manner as the shape and the non-uniform thickness of the insulating coating layer.

In order to solve the above problems, the present invention is a wire processing die for deforming and drawing out a round electric wire having a circular cross section provided with an insulating coating layer on a conductor surface into a deformed electric wire having a polygonal cross section,
The cross-sectional shape of the machining hole in the axial direction through which the electric wire is continuously penetrated is such that the entrance on the round wire insertion side is circular and the outlet to be drawn out as the deformed electric wire is polygonal, and the axial direction from the entrance to the exit is circular. An electric wire machining die characterized by continuously changing into a polygon is provided.

As described above, in the present invention, the cross-sectional shape of the entrance of the die processing hole is circular. By adopting such a shape, the deformation pressure applied to the insulating coating layer on the outer periphery of the round electric wire when the round electric wire is inserted into the processing hole of the die can be made minute, and the occurrence of damage to the insulating coating layer can be surely prevented.
In addition, the polygonal cross-sectionally processed hole is continuously and smoothly changed from a circular shape to a polygonal shape from the inlet to the outlet, and the round electric wire is gradually and continuously deformed into a polygon. No sudden deformation pressure is applied. As a result, a deformed electric wire having a polygonal cross section can be finally obtained while preventing damage to the insulating coating layer.
In addition, the cross-sectional shape of the inlet of the die processing hole is circular, and the deformation pressure applied to the insulating coating layer on the outer periphery of the round wire is eliminated when the round wire is inserted into the die processing hole. It is possible to prevent the center axis from deviating from the center axis of the deformed hole. Furthermore, since the cross-sectional shape of the processed hole is continuously and smoothly changed from a circular shape to a polygonal shape, the center axis of the electric wire can be passed while being centered with the axis of the processed hole, and the electric wire has the same shape as the die. The deformation pressure is evenly applied to the circular insulating coating layer, and damage to the insulating coating layer and uneven thickness can be prevented.

In addition, you may make the cross-sectional area of the cross-sectional polygon of the exit of a die | dye smaller than the cross-sectional area of a round electric wire.
According to the said structure, by drawing a round electric wire through the process hole of a die | dye, the deformation | transformation to the cross-sectional polygon of an electric wire can be performed and the wire drawing of a round electric wire can also be performed.

Further, the processing hole of the die is formed between an introduction hole and a lead-out hole that are continuous in the axial direction, and the inlet of the processing hole is continuous with the introduction hole reduced in diameter into a conical shape, and the outlet of the processing hole Is continuous with the lead-out hole expanded in a conical shape,
It is preferable that the cross-sectional area of the inlet of the processed hole is 30% to 50% larger than the cross-sectional area of the round electric wire.
Further, it is preferable to reduce the diameter of the machining hole from the inlet to the outlet at an angle of 10 degrees to 18 degrees in the axial direction.
If the cross-sectional area of the inlet is larger than the cross-sectional area of the round electric wire by more than 50% or the angle of diameter reduction is larger than 18 degrees, the round electric wire can be easily inserted into the processing hole, and the workability is good. This is because the cross-sectional shape suddenly changes from a circular shape to a polygonal shape, and a sudden deformation pressure is applied to the insulating coating layer of the round electric wire, which may damage the insulating coating layer. Further, when the cross-sectional area of the entrance is larger than the cross-sectional area of the round electric wire by less than 30%, or the angle of diameter reduction is less than 10 degrees, there is no great difference in the cross-sectional area of the entrance of the processing hole of the round electric wire and the die. For this reason, it becomes difficult to insert the round electric wire into the entrance of the machining hole, and the workability is deteriorated.

The dice of the present invention may be divided into a plurality of stages or a continuous one-stage die in the axial direction from the entrance to the exit of the processing hole.
When the dice are divided into multiple stages, the round electric wire can be made into a deformed electric wire with the required cross-sectional shape through the multiple dice, so the change in the cross-sectional shape of the processed hole for each step can be reduced and the electric wire The deformation can be performed gently, and the burden on the electric wire can be reduced.
On the other hand, in the case where the dies are arranged in a single stage, the irregular electric wire having a required cross-sectional shape can be obtained simply by passing the round electric wire once through the die, so that the facilities are simplified.

As a second invention, an odd-shaped electric wire manufactured by the above method is provided.
The odd-shaped electric wire is made of enameled wire having a square cross section or a hexagonal cross section, for example, and is coiled by aligned winding.

As described above, when using a deformed electric wire having a square cross section when coiled, it can be wound without generating a gap in both the axial direction and the radial direction of the coil, and the corner of the cross section of the deformed electric wire Since the (vertical angle) is not greatly rounded and the corner (vertical angle) does not have a large radius, the wire occupation ratio can be increased as compared with the case where the coil is formed with a round wire.
In addition, even when the coil is formed by aligning windings as a hexagonal cross-section shaped electric wire, no gap is generated between the radial layers, and as a result, no gap is generated in the axial direction. Since the corner (vertical angle) is not rounded and the corner (vertical angle) does not have a large radius, the wire occupation ratio can be increased.

  The deformed electric wire of the present invention is not limited to the enameled electric wire, and an insulating coating layer made of another material may be provided. Moreover, the cross-sectional shape of the odd-shaped electric wire may be a cross-sectional triangle, pentagon, or octagon according to the application.

As described above, according to the die for electric wire processing of the present invention, since the cross-sectional shape of the inlet of the die processing hole is circular, the insulation of the outer periphery of the round electric wire when the round electric wire is inserted into the processing hole of the die The deformation pressure applied to the coating layer can be made minute, and it is possible to reliably prevent the insulation coating layer from being damaged and the insulation coating layer from becoming uneven in thickness.
Further, when the deformed electric wire manufactured using the die is wound into a coil, the coil can be wound without generating a gap in either the axial direction or the radial direction of the coil, and the corner of the cross section of the deformed electric wire Since the (vertical angle) is not greatly rounded and the corner (vertical angle) does not have a large radius, the wire occupation ratio can be increased as compared with the case where the coil is formed with a round wire.

Embodiments of the present invention will be described with reference to the drawings.
1 to 7 show a first embodiment of the present invention.
The wire processing die 10 is continuously provided with an introduction hole 14, a processing hole 13, and a lead-out hole 15 that are penetrated in the axial direction, and a round electric wire 20 inserted from the introduction hole 14 is formed into a hexagonal cross section at the processing hole 13. It is deformed to 20A and pulled out from the outlet hole 15.

  The cross-sectional shape of the machining hole 13 of the die 10 is such that the inlet 13a is circular as shown in FIG. 1 (A), the outlet 13b is a regular hexagon shown in FIG. 1 (B), and from the inlet 13a to the outlet 13b as shown in FIG. It is made to continue smoothly from the circle shown to a regular hexagon.

As shown in FIG. 3A, the diameter L1 of the inlet 13a having a circular cross section of the processed hole 13 is set to be equal to or larger than the diameter L2 of the round electric wire 20. In this embodiment, the diameter L1 of the inlet 13a is 1.27 mm, the diameter L2 of the round electric wire 20 is 1.08 mm, and the cross-sectional area of the inlet 13a is 40% larger than the cross-sectional area of the round electric wire 20.
As shown in FIG. 3B, the cross-sectional area of the regular hexagonal outlet 13b of the processed hole 13 drawn out as the hexagonal deformed electric wire 20A is substantially the same as the cross-sectional area of the round electric wire 20.
In this embodiment, the reduction angle α from the inlet 13a to the outlet 13b, which changes smoothly from a circular shape to a polygonal shape, is reduced to 14 degrees as shown in FIG. The length X is about 4 mm.
In this embodiment, the die 10 is formed of sintered diamond, but may be formed of other materials.

The introduction hole 14 that is continuous with the machining hole 13 of the die 10 in the axial direction is reduced in diameter to a conical shape from the introduction opening side at the tip, whereas the outlet hole 15 that is continuous with the outlet 13b of the machining hole 13 is conical. The diameter is expanded.
The introduction hole 14 is formed of a first introduction hole 14a and a second introduction hole 14b by changing the angle in two stages, and the diameters of the respective diameters (reduction angles) are different. In the present embodiment, the first introduction hole 14a is reduced in diameter (reduction angle) to 70 degrees, and the second introduction hole 14b is set to 40 degrees to facilitate introduction of the round wire 20 into the inlet 13a of the machining hole 13. .
Similarly, the lead-out hole 15 is also composed of first to third lead-out holes 15a to 15c whose angles are changed in three stages. In this embodiment, the diameters to be expanded are 0 degrees, 20 degrees, and 50 degrees, respectively. This makes it easier to lead out the deformed electric wire 20A from the outlet 13b. The first outlet hole 15a has a hexagonal cross section similar to the outlet 13b of the machining hole 13, and the second outlet hole 15b is similar to the sectional shape of the outlet of the first outlet hole 15a, that is, the sectional shape of the outlet 13b of the machining hole 13. The diameter of the third lead-out hole 15c is increased from a hexagonal cross section to a circular cross section.

As shown in FIG. 5A, the round electric wire 20 inserted into the processed hole 13 has a circular cross section and includes an insulating coating layer 20b made of enamel on the surface of the conductor 20a.
The deformed electric wire 20A drawn out from the processed hole 13 has the same cross-sectional area as the round electric wire 20, has a regular hexagonal cross-sectional shape as shown in FIG. 3B, and has a uniform thickness on the entire surface of the conductor 20a. The insulating coating layer 20b made of

The round electric wire 20 is drawn into the introduction hole 14 in which the die 10 is expanded in a conical shape, introduced into the inlet 13a of the machining hole 13, and brought into contact with the inner surface of the machining hole 13 to be deformed. A deformed electric wire 20A having a regular hexagonal cross section having the same shape as 13b is drawn out to the lead-out hole 15 having an enlarged diameter.
The drawing speed of the round electric wire 20 in the die 10 is in the range of 10 to 30 m / min.

When the round electric wire 20 is processed from the round electric wire 20 to the deformed electric wire 21 by the die 10, the cross-sectional shape of the inlet 13 a of the processing hole 13 is circular, so the round electric wire 20 at the time when the round electric wire 20 is inserted into the processed hole 13 of the die 10. The deformation pressure applied to the outer insulating coating layer 20b can be made minute, and the occurrence of damage to the insulating coating layer 20b and the uneven thickness of the insulating coating layer can be reliably prevented.
In addition, since the circular wire 20 is smoothly and continuously changed from the circular shape to the hexagonal shape from the inlet 13a to the outlet 13b, the round electric wire 20 is not subjected to an abrupt deformation pressure at any stage of being drawn out of the machining hole 13, It is possible to prevent the insulating coating layer 20b from being damaged during the drawing process. And in the state pulled out from the exit 13b as the unusual shape electric wire 20A of a hexagonal cross section, it can be drawn out as an irregular shape electric wire provided with the insulation coating layer 20b of uniform thickness on each side and each apex angle. Moreover, it is possible to provide a modified electric wire in which the corner (vertical angle) of the cross section is not greatly rounded and the corner (vertical angle) does not have a large radius.

  In the above-described embodiment, the outlet 13b of the processing hole 13 has a hexagonal cross section. As shown in FIG. 6, the corner (vertical angle) of the hexagonal cross section has a small radius of R = 0.2 mm or less. May be. By attaching a small radius, it is possible to prevent the insulation coating layer 20b of the deformed electric wire 20A from being damaged during the drawing process, and when forming the coil with the deformed electric wire 20A, the corners of the hexagonal cross section of the deformed electric wire 20A The winding space factor is not reduced by the are.

Moreover, although the said embodiment manufactures the odd-shaped electric wire of a cross-sectional hexagon, as shown in FIG. 7, the cross-sectional shape of the exit 13b of the process hole 13 of the die | dye 10 is made into square shape, and a round electric wire is drawing-out processing of a die | dye. Thus, a deformed electric wire having a square cross section may be used.
Also in this case, the entrance of the machining hole 13 has a circular cross section as in the above-described embodiment, and smoothly changes from a circular shape to a square shape continuously from the entrance to the exit 13b.

FIG. 8 shows a second embodiment in which a coil is formed using a deformed electric wire having a hexagonal cross section processed using the die 10 described in the first embodiment.
The deformed electric wire 20 </ b> A forming the coil is made of an enameled wire having a hexagonal cross section and is wound in an aligned manner to form a coil 22.

Specifically, after the first row is wound in the axial direction Z1 → Z2 of the bobbin 23 made of a cylindrical body, the second row is wound back by turning back to Z2 → Z1, and this reciprocation is performed in the third and fourth rows. Are aligned and wound to form a multilayer coil 22.
At the time of winding, one side 20c of a regular hexagonal cross section is set to a direction orthogonal to the axial direction Z, and the odd-shaped electric wire 20A is wound with the sides adjacent to each other in the axial direction coming into contact with each other. The convex portions 20d of the vertical angle and the concave portions 20e between the sides of the adjacent deformed electric wires 20A are alternately present. By repeating this, the deformed electric wire 20A is wound at a high density with no gap between the layers.

Thus, when the coil 22 is formed by aligned winding using the deformed electric wire 20A having a hexagonal cross section, the corner (vertical angle) of the cross section is not greatly rounded and the corner (vertical angle) does not have a large radius. The deformed electric wire 20A can be wound without any gap in both the direction and the axial direction, and the electric wire space factor of the coil 22 can be improved.
In addition, the deformed electric wire 20 </ b> A has a high insulation reliability and a high-quality coil 22 because the insulating coating layer made of the enamel layer is not damaged and is not uneven using the die 10. it can.
In addition, also when a coil is formed using the odd-shaped electric wire of the cross-sectional square shape formed with the die | dye of this invention, the electric wire occupation rate of a coil can be raised.

  In addition, this invention is not limited to the said embodiment, The various form within the claim of this invention is included.

It is a perspective view of the dice for electric wire processing of a 1st embodiment. (A) is a side view on the introduction side of the die, (B) is a sectional view in the axial direction of the die, and (C) is a side view on the lead side of the die. (A) is a front view of the entrance of the machining hole on the round wire insertion side of the die, (B) is a front view of the exit, and (C) is a drawing showing the relationship between the entrance and the outlet. It is a figure which pulls out a deformed electric wire from a processing hole. (A) is sectional drawing of a round electric wire, (B) is sectional drawing of a deformed electric wire. It is a perspective view of the die | dye in the case of attaching a radius to the vertex part of the irregular shaped electric wire made into a regular hexagonal cross section. It is the figure which made the processed hole of die | dye the cross-sectional square shape. It is a figure which shows 2nd Embodiment which used the deformed electric wire of this invention as the coil. It is a figure which shows a prior art example.

Explanation of symbols

10 Die 13 Processing hole 13a Inlet 13b Outlet 14 Inlet hole 15 Outlet hole 20 Round electric wire 20A Deformed electric wire 20b Insulating coating layer 22 Coil L1 Diameter of inlet cross section L2 Diameter of round electric wire

Claims (4)

A wire processing die for transforming and drawing out a round electric wire having a circular cross section with an insulating coating layer on the conductor surface into a deformed electric wire having a polygonal cross section,
The cross-sectional shape of the machining hole in the axial direction through which the electric wire is continuously penetrated is such that the entrance on the round wire insertion side is circular and the outlet to be drawn out as the deformed electric wire is polygonal, and the axial direction from the entrance to the exit is circular. Dies for wire processing, characterized by continuously changing into polygons. The processing hole of the die is formed between an introduction hole and a lead-out hole that are continuous in the axial direction. The entrance of the processing hole is continuous with the introduction hole that has been reduced in diameter to a conical shape, and the exit of the processing hole is a cone. Continuing on the lead-out hole expanded in shape,
The die for electric wire processing according to claim 1, wherein a cross-sectional area of the inlet of the processing hole is 30% to 50% larger than a cross-sectional area of the round electric wire.   A deformed electric wire processed by the die according to claim 1.   The deformed electric wire according to claim 3, which is made of enameled wire having a hexagonal cross section or a quadrangular cross section, and is formed into a coil by aligned winding.

Images