JP6567785B2 - Coil manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a coil using a rectangular conductor.

  Examples of the coil device in which the coil is disposed around the core (stator core) of the stator core (stator) include electric devices such as a motor, a generator, a transformer, and the like. In order to reduce the size and size, it is important to improve the space factor of the coil in the core.

  Conventionally, a coil using a rectangular conductor (hereinafter referred to as a rectangular coil) is known as a coil capable of improving the space factor in the core. A flat coil is also called a flat (square) coil, a square (square) coil, an edgewise coil, etc., and is used for a coil wound with a round conductor whose cross-section perpendicular to the longitudinal direction is substantially circular. A coil in which a rectangular conductor having a rectangular cross-section perpendicular to the longitudinal direction is wound.

  As a method for manufacturing a rectangular coil, a method of winding a long rectangular conductor (square conductor) into a substantially rectangular shape is known (for example, see Patent Document 1). Also known is a method in which a rectangular conductor (flat conductive material) with a length of one turn of the coil is laminated, and the lower end upper surface and the upper start lower surface are overlapped and repeated by a joining means to form a spiral structure. (For example, refer to Patent Document 2).

  As a conductor connection method, a cold pressure welding method is known.

Japanese Patent No. 3881520 JP 2005-130676 A

  However, in the method of winding a long flat rectangular conductor wire into a substantially rectangular shape as in the technique described in Patent Document 1, the corners (both on the outer peripheral side and the inner peripheral side) are curved and rounded. It is inevitable. Since the core is generally in the shape of a prism having a substantially right corner, if a rounded coil is disposed around the core, a space is generated between the core and the coil. Since this space accumulates heat during operation of the coil device, the heat dissipation of the coil device deteriorates, and there is a problem that the efficiency of the coil device cannot be increased due to an increase in coil resistance. In addition, there is a limit to improving the coil space factor at the corners.

  In addition, since the outer periphery of the rectangular conductor wire used for the coil is coated with an insulating resin in advance, the winding of the rectangular conductor becomes thin due to the bending at the corners on the outer periphery side, which reduces the withstand voltage of the coil device. there were.

  On the other hand, in the case of a method of laminating and joining a rectangular conductor for one turn of a coil as in the technique described in Patent Document 2, it is possible to prevent the corners from being bent, and the above-described heat dissipation and space factor. This problem can be avoided. However, although it is connected by the joining means, it is inevitable that the characteristics of the joined portion between the lower end surface of the upper stage and the lower surface of the upper end of the upper stage are deteriorated as compared with the uncut portion. Problems remain in terms.

  Furthermore, as one of the methods for connecting conductors, a method of cold welding the round wire conductors is known, but flat conductors are cold-welded by improving the stability of the connection part well. It was difficult.

  An object of the present invention is to provide a method for manufacturing a coil using a rectangular conductor, which can improve the space factor and heat dissipation, and does not cause characteristic deterioration due to cutting and joining.

  The present invention solves the above problems by the following means.

The present invention, when the continuous strip-shaped flat conductor that can be helical structure by preparing a plurality of a method of manufacturing a coil for forming a plurality of said flat conductor end faces the helical structure by seaming the ends of the spiral The structure has a corner portion, which is a region where the spiral traveling direction changes, and a straight portion, and has one end face in the band longitudinal direction of the first flat conductor and one band longitudinal direction in the second flat conductor. A pressure-contacting process in which the end face of the belt is abutted and pressed in the region to be the straight part, and a removal process of removing burrs protruding in a direction intersecting the band longitudinal direction and the band transverse direction by the pressing. It is the manufacturing method of the coil characterized.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the coil using a rectangular conductor which can improve a space factor and can improve heat dissipation, and does not produce the characteristic deterioration by a cutting | disconnection and joining can be provided.

(A) It is the external view (front view) which showed typically the structure of the cold pressure welding apparatus which concerns on this embodiment partially. (B) It is a top view of a flat conductor. (C) It is the sectional view on the AA line of FIG.1 (b). It is the external view (front view) which showed typically the holding | maintenance part of the cold welding apparatus which concerns on this embodiment. It is the external view (front view) which showed typically the holding | maintenance part of the cold welding apparatus which concerns on this embodiment. It is the side view which showed typically the holding | maintenance part of the cold welding apparatus which concerns on this embodiment. It is a top view which shows the flat conductor which concerns on this embodiment. It is a schematic diagram which shows the mode of the cold pressure welding of the flat conductor which concerns on this embodiment. It is a figure which shows the coil manufacturing apparatus which concerns on this embodiment, (a) It is a side view of a holding part, (b) It is a front view of a coil, (c) It is a front view of a holding part. It is a side view of the holding | maintenance part of the coil manufacturing apparatus which concerns on this embodiment. It is a schematic diagram explaining the coil manufacturing method which concerns on this embodiment. It is a schematic diagram explaining the coil manufacturing method which concerns on this embodiment. It is a modification of the coil piece which concerns on this embodiment. It is a figure explaining the modification of the coil manufacturing apparatus and coil manufacturing method which concern on this embodiment. It is a figure explaining the coil which concerns on this embodiment, (a) It is a front view, (b) It is sectional drawing, (c) It is a side view. It is a figure which shows the experimental result about the emitted-heat amount of the coil which concerns on this embodiment, and the coil of a prior art example. It is a figure explaining the attachment method to the status core of the coil which concerns on this embodiment, (a) It is a side view, (b) It is sectional drawing of the figure (a), (c) The figure (a) FIG. It is a side view which shows the helical structure of the coil which concerns on this embodiment. It is a figure which shows the helical structure of the coil which concerns on this embodiment, (a) external appearance perspective view, (b) side view, (c) external appearance perspective view, (d) side view.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Cold welding equipment>
FIG. 1 is a diagram illustrating a cold pressure welding apparatus 10 according to the present embodiment, and FIG. 1A is an external view (front view) schematically showing a part of the configuration of the cold pressure welding apparatus 10. FIG. 1B is a top view of the flat conductor C, and FIG. 1C is a cross-sectional view taken along line AA in FIG.

  As shown in FIG. 1A, the cold pressure welding apparatus 10 is a device for cold pressure welding two flat conductors C (C1, C2), and includes a first holding part 11 and a second holding part 12. Have. In the following description, the flat conductor C refers to a strip-shaped (tape-shaped) conductor configured in a plane with respect to a round wire conductor, as shown in FIGS. That is, the flat conductor is a band-shaped member having two wide surfaces WS facing each other and two narrow surfaces WT facing each other and being long in a predetermined direction, as shown in FIGS. The cross section perpendicular to the belt longitudinal direction BL (the cross section taken along the line AA in FIG. 4B) is a rectangular or rounded rectangular conductor as shown in FIG. In the following description, as an example of a flat conductor, a rectangular conductor whose cross section orthogonal to the longitudinal direction of the band is rectangular (the upper diagrams of FIGS. 5B and 5C) will be described as an example. In addition, the flat conductor C in the present invention may be a strip-shaped conductor configured in a plane with respect to the round wire conductor, and has a substantially square cross-sectional view in the section AA in FIG. It may be.

  The first holding part 11 is movable along the first direction (the longitudinal direction of the rectangular conductor band; the X direction in FIG. 5A). The first holding part 111 and the first lower holding part 112 Composed. The first upper holding body 111 and the first lower holding body 112 are arranged to face each other so as to have an opposing surface OS1 along the first direction (hereinafter referred to as the X direction). In the present embodiment, for convenience of explanation, the upper holding body shown in the drawing is referred to as a first upper holding body 111, and the lower holding body shown in the drawing is referred to as a first lower holding body 112. It is not limited to above and below. That is, FIG. 1A may be a top view of the cold pressure welding apparatus 10, in which case the first upper holding body 111 is, for example, a rear holding body, and the first lower holding body 112 is, for example, the front side. It becomes the side holder. The first upper holding body 111 may be, for example, a left holding body, and the first lower holding body 112 may be, for example, a right holding body.

  The first upper holding body 111 and the first lower holding body 112 are movable along the X direction, and the opposing surface OS1 along the X direction has a second direction (the plate thickness direction of the flat conductor; It can move along the Y direction in FIG. The Y direction is a direction different from the X direction, for example, a direction orthogonal to the X direction.

  The second holding part 12 is arranged to face the first holding part 11 so as to have an opposing surface OS2 along the second direction (hereinafter referred to as Y direction) between the first holding part 11 and A configuration similar to that of the first holding unit 11 is provided. Therefore, although a detailed description is omitted, the second holding unit 12 is movable along the X direction, and includes the second upper holding body 121 and the second lower holding body 122. The description of “upper and lower” of the second upper holding body 121 and the second lower holding body 122 is the same as that of the first holding unit 11.

  The second upper holding body 121 and the second lower holding body 122 can move along the X direction, and can move so that the opposing surface OS1 abuts or separates from each other along the Y direction.

  Moreover, the 1st holding | maintenance part 11 and the 2nd holding | maintenance part 12 are urged | biased by the urging | biasing member (for example, coil spring) 15 in the direction spaced apart from each other along the X direction. Although not shown, the first upper holding body 111 and the first lower holding body 112 are urged by a urging member (for example, a coil spring) in a direction away from each other along the Y direction, and the second The upper holding body 121 and the second lower holding body 122 are biased by a biasing member (for example, a coil spring) in a direction away from each other along the Y direction.

  The movement of the first rectangular conductor C1 and the second rectangular conductor C2 in the Y direction is restricted by a movement restricting means (not shown). Further, the first rectangular conductor C1 and the second rectangular conductor C2 can move in the direction close to each other along the X direction, but are restricted from moving in the direction away from each other.

    In addition, a pressing portion 18 is provided outside the first holding portion 11 and the second holding portion 12 in the Y direction. The pressing unit 18 presses the first upper holding body 111 and the first lower holding body 112 so as to contact each other, and the second upper holding body 121 and the second lower holding body 122 contact each other. Press these.

  FIGS. 2 and 3 are front views in which the first holding unit 11 and the second holding unit 12 are extracted, and are diagrams illustrating the state of movement of these.

  2 mainly shows the first holding portion 11 (first upper holding body 111 and first lower holding body 112) and second holding portion 12 (second upper holding body 121 and second lower holding body 122). It is a figure explaining the movement along a direction.

  In the state shown in FIG. 6A, the opposing surfaces OS1 of the first upper holding body 111 and the first lower holding body 112 (the same applies to the second upper holding body 121 and the second lower holding body 122) are the most in the Y direction. It is a position to be separated. Hereinafter, this position is referred to as a Y-direction separation position. Further, this state is a position where the opposing surfaces OS2 of the first holding unit 11 and the second holding unit 12 are most separated from each other in the X direction, and this position is hereinafter referred to as an X direction separation position.

  FIG. 6B shows a state where the first upper holding body 111 and the first lower holding body 112 have moved from the state shown in FIG. In this state, the first holding unit 11 sandwiches the first flat conductor (the wide surface WS thereof) by the first upper holding body 111 and the first lower holding body 112, and the second holding unit 12 is the second upper holding body 121. And the second lower holding body 122 sandwich the second rectangular conductor (the wide surface WS thereof).

  The 1st holding | maintenance part 11 protrudes and clamps the 1st flat conductor C1 to the 2nd holding | maintenance part 12 direction from opposing surface OS2 along a Y direction. Similarly, the 2nd holding | maintenance part 12 protrudes the 2nd flat conductor C2 to the 1st holding | maintenance part 11 direction from opposing surface OS2 along a Y direction, and is clamped. The protrusion amount A1 of the first flat conductor C1 from the first holding portion 11 and the protrusion amount A2 of the second flat conductor C2 from the second holding portion 12 will be described later.

  The position where the opposing surfaces OS1 of the first upper holding body 111 and the first lower holding body 112 (the second upper holding body 121 and the second lower holding body 122) abut on each other is referred to as a clamping position in the following description. That is, the first upper holding body 111 and the first lower holding body 112 (the second upper holding body 121 and the second lower holding body 122) can move between the sandwiching position and the Y direction separation position.

  Further, as shown in FIG. 5C, a nipping release position (in the Y direction) is included between the nipping position and the Y direction separation position. The release position in the Y direction (hereinafter referred to as the Y direction release position) is a distance smaller than the Y direction separation position, and the first upper holding body 111 and the first lower holding body 112 (the second upper holding body 121 and the second lower holding body). The body 122) is spaced apart.

  From the Y-direction release position in FIG. 6C, the position where the opposing surface OS1 of the first upper holding body 111 and the first lower holding body 112 (the second upper holding body 121 and the second lower holding body 122) abuts. It is also possible to move to the state shown in FIG.

  In FIG. 2, the positions of the first holding unit 11 and the second holding unit 12 along the X direction are maintained at the X direction separation position.

FIG. 3 is a diagram illustrating the movement of the first holding unit 11 and the second holding unit 12 mainly along the X direction.
FIG. 3A shows a position where the first holding unit 11 and the second holding unit 12 have moved along the X direction so that the opposed surface OS2 is closest to the state of FIG. Hereinafter, this position is referred to as a proximity position. That is, the 1st holding | maintenance part 11 and the 2nd holding | maintenance part 12 are movable between the X direction separation position shown in FIG. 2, and the proximity position shown to Fig.3 (a). Even if it is a proximity position, the 1st holding | maintenance part 11 and the 2nd holding | maintenance part 12 do not contact | abut.

  The first holding portion 11 holds the first flat conductor C1 with the protruding amount A, and the second holding portion 12 holds the second flat conductor C2 with the protruding amount A2 ( 2 (b)), when the first holding part 11 and the second holding part 12 are in the proximity position, the first holding part 11 and the second holding part 12 do not come into contact with each other, but the first rectangular conductor C1 and the second holding part 12 are not in contact with each other. The flat conductor C2 comes into contact (joining) and is pressed against each other. That is, the protrusion amount A1 of the first flat conductor C1 from the first holding portion 11 and the protrusion amount A2 of the second flat conductor C2 from the second holding portion 12 are respectively the first holding portion 11 and the second holding portion 12. When the two are close to each other, the amount is slightly longer than the length of contact with each other (the amount that can be pressed together after contact).

  Also, as shown in FIG. 2B, a pressing release position (in the X direction) is included between the proximity position and the X direction separation position (FIG. 2A). The release position in the X direction (hereinafter referred to as the X direction release position) is a position where the first holding unit 11 and the second holding unit 12 are separated by a distance smaller than the X direction separation position. When the first holding unit 11 and the second holding unit 12 are in the X-direction release position, the first upper holding body 111 and the first lower holding body 112 are also moved away to the Y-direction release position, and the second upper holding body 121 and the second lower holding body 122 are also moved away to the Y-direction release position.

  In addition, it can also change to the state shown to the figure (a) from the X direction cancellation | release position of the figure (b).

  FIG. 4 is a side view of the first holding unit 11 as viewed from the second holding unit 12 side on the facing surface OS2 of the first holding unit 11 (viewed in the direction of arrow V in FIG. 1). FIG. 2A shows a state where the first upper holding body 111 and the first lower holding body 112 are separated from each other in the Y direction (the state shown in FIG. 2A), and FIG. The state in the state (Fig. 2 (b)) is shown.

  The first upper holding body 111 has a rectangular conductor holding groove 111A at a position close to one end face (right end face in the drawing) 111S in the third direction (the rectangular short band direction of the rectangular conductor; the Z direction in the figure). The first lower holding body 112 is provided with a rectangular conductor holding groove 112A at a position close to one end face (right end face in the drawing) 112S in the third direction (hereinafter referred to as Z direction). The third direction (Z direction) is a direction different from the X direction and the Y direction, respectively, and is a direction orthogonal to both in this case.

  One end face 111S of the first upper holding body 111 and one end face 112S of the first lower holding body 112 are located on the same plane, and one end face in the third direction (Z direction) 1 is the front of the first upper holding body 111 and the first lower holding body 112, and is the end face close to the operator.

  The rectangular conductor holding grooves 111A and 112A are located on the inner side of the first upper holding body 111 and the end surfaces 111S and 112S of the first lower holding body 112 at a distance d1 in the third direction (Z direction), and the first upper holding body. It is a rectangular groove provided on the opposing surface OS1 of the body 111 and the first lower holding body 112.

  Further, as will be described in detail later, the rectangular conductor holding grooves 111A and 112A need to reliably hold (clamp) the rectangular conductor. Therefore, the shape is along the outer shape of the flat conductor, and the depth d3 of the groove is less than half the thickness d2 of the sandwiched flat conductor (here, the first flat conductor C1). . Specifically, the depths of the rectangular conductor holding grooves 111A and 112A are about 5/100 mm smaller than ½ of the thickness d2 of the rectangular conductor.

  As shown in FIG. 2B, when the opposing surfaces OS1 of the first upper holding body 111 and the first lower holding body 112 are in contact (when in the clamping position (FIG. 2B)), the rectangular conductor The holding grooves 111A and 112A become one square columnar hole that penetrates the first holding part 11 in the X direction, and a flat conductor (first flat conductor C1) is compressed in the plate thickness d2 direction into the hole. In a state (a state where the plate thickness is reduced), the flat conductor holding grooves 111A and 112A are in close contact with each other, and are held between the first holding portions 11 (the first upper holding body 111 and the first lower holding body 112).

  Although illustration is omitted here, the same applies to the second holding unit 12, and the second upper holding member 121 has one end face (front face close to the operator) in the third direction (Z direction). A rectangular conductor holding groove 121A is provided at a position close to the second lower holding body 122, and a rectangular conductor holding groove 122A is provided on the second lower holding body 122 at a position close to one end face in the third direction. The configuration of the flat conductor holding grooves 121A and 122A is the same as that of the flat conductor holding grooves 111A and 112A of the first holding unit 11.

  The 1st holding | maintenance part 11 and the 2nd holding | maintenance part 12 will be in any state of a clamping state, a press-contact state, a press-contact release state, a retreat state, and the transition state between these two states.

  2 and 3 again, in the clamping state, the first upper holding body 111 and the first lower holding body 112 of the first holding unit 11 are separated from each other in the Y direction along the Y direction (see FIG. 2 ( a)) to the clamping position (FIG. 2B), the first flat rectangular conductor C1 is clamped by the first upper holding body 111 and the first lower holding body 112, and the second holding part 12 The upper holding body 121 and the second lower holding body 122 are moved along the Y direction from the Y direction separation position (FIG. 2A) to the clamping position (FIG. 2B), and the second upper holding body 121 and The second flat conductor C2 is sandwiched between the second lower holding bodies 122.

  As described above, the first holding unit 11 sandwiches the first flat rectangular conductor C1 in the direction of the second holding unit 12 from the facing surface OS2 along the Y direction by the protruding amount A1, and the second holding unit 12 includes: The second flat conductor C2 is protruded from the facing surface OS2 along the Y direction in the direction of the first holding portion 11 by the protruding amount A2, and is sandwiched.

  At this time, the pressing portion 18 (see FIG. 1A) presses the first upper holding body 111 and the first lower holding body 112 so as to contact each other, and the second upper holding body 121 and the second lower holding body. These are pressed so that the body 122 contacts. Accordingly, the first rectangular conductor C1 and the second rectangular conductor C2 are in close contact with the rectangular conductor holding grooves 111A, 112A, 121A, and 122A in a state where the first rectangular conductor C1 and the second rectangular conductor C2 are compressed in the thickness direction (the thickness is reduced). It is sandwiched between the holding part 11 and the second holding part 12 (see FIG. 4).

  Further, in the clamping state, the first upper holding body 111 and the first lower holding body 112 of the first holding unit 11 in the Y-direction release position (FIG. 2C) are in the clamping position (FIG. 2B). The first upper holding body 111 and the first lower holding body 112 are clamped to hold the first flat rectangular conductor C1, and the second upper portion of the second holding portion 12 at the Y-direction release position (FIG. 2C) is moved. In some cases, the holding body 121 and the second lower holding body 122 are moved to the holding position (FIG. 2B) to hold the second flat conductor C2 between the second upper holding body 121 and the second lower holding body 122. is there.

  Also at this time, the pressing portion 18 presses the first upper holding body 111 and the first lower holding body 112 so as to contact each other, and the second upper holding body 121 and the second lower holding body 122 come into contact with each other. Press these. Accordingly, the rectangular conductor holding grooves 111A, 112A, 121A, 122A and the first rectangular conductor C1 and the second rectangular conductor C2 are compressed in the plate thickness direction (the plate thickness is reduced) in the holes. They are in close contact with each other and are sandwiched between the first holding part 11 and the second holding part 12 (FIG. 4).

  In the pressure contact state, the first holding part 11 and the second holding part 12 in the sandwiched state are moved from the X direction separation position (FIG. 2A) along the X direction against the urging force of the urging member 15. It moves to the proximity position (FIG. 3A). At this time, the first flat conductor C <b> 1 protrudes from the first holding part 11, and the second flat conductor C <b> 2 protrudes from the second holding part 12. These protrusion amounts A1 and A2 are based on the lengths of the end faces facing each other in the longitudinal direction of the belt when the first holding part 11 and the second holding part 12 are in the close position (FIG. 3A), respectively. The amount is slightly longer. That is, before moving to the close position (immediately before), the opposing end surfaces of the first flat conductor C1 and the second flat conductor C2 first contact (abut). Thereafter, the first holding part 11 and the second holding part 12 move to the close position (FIG. 3A), so that the contacted end faces of the first flat conductor C1 and the second flat conductor C2 protrude from each other. Combined, pressed and joined. More specifically, by pressing the end faces of the first rectangular conductor C1 and the second rectangular conductor C2, the stable oxide film formed on the end faces is removed, and these are plastically deformed to be in an active state. Expose the surface. The active surfaces are brought closer to 10 angstroms or less, thereby causing an atomic bond between the metals and performing cold welding. That is, by cold welding, the first rectangular conductor C1 and the second rectangular conductor C2 are compressed (shortened) after the pressure welding in comparison with the length before the pressure welding in the longitudinal direction of the band. The shortening amount is the same in the first rectangular conductor C1 and the second rectangular conductor C2. That is, when the length of the first flat conductor C1 before press contact is L01 and the length of the second flat conductor C2 before press contact is L02, the length of the first flat conductor C1 is L01 ′ and the second length by press contact. The flat conductor C2 has a length shortened to L02 ′, and the amount of shortening S is the same (S = L01−L01 ′ = L02−L02 ′).

  In addition, after moving to a proximity position, since the 1st holding | maintenance part 11 and the 2nd holding | maintenance part 12 do not adjoin any more, it is beyond that of the end surfaces of the 1st flat conductor C1 and the 2nd flat conductor C2. The pressing stops.

  Further, in the pressure contact state, the first upper holding body 111 and the first lower holding body 112 at the Y direction release position (FIG. 2C), or at the Y direction release position and the X direction release position (FIG. 3B). In addition, the second upper holding body 121 and the second lower holding body 122 are moved to the holding position (FIG. 2B), and the first holding portion 11 and the second holding portion 12 are resisted against the urging force of the urging member 15. Then, the end face of the first flat conductor C1 and the end face of the second flat conductor C2 are abutted and pressed to perform cold pressure welding (FIG. 3A).

  In the pressure release state, the first holding unit 11 and the second holding unit 12 that are in the pressure contact state are moved away from each other along the X direction, and the first holding unit 11 and the second holding unit 12 are moved to the X direction release position. Move to. Further, the first upper holding body 111 and the first lower holding body 112 are moved in the direction away from each other along the Y direction, and the first upper holding body 111 and the first lower holding body 112 are moved to the first Y direction release position. To do. Further, the second upper holding body 121 and the second lower holding body 122 are moved in the direction away from each other along the Y direction, and the second upper holding body 121 and the second lower holding body 122 are moved to the second Y direction release position. (FIG. 3B).

  In the pressure contact state, the first holding part 11 and the second holding part 12 finally reach the close position, and further pressing of the first flat conductor C1 and the second flat conductor C2 stops, so that the pressing is repeated. After the pressure contact state, the state transitions to the sandwiching state via the pressure release state, and the first and second rectangular conductors C1 and C2 are sandwiched again by the first holding unit 11 and the second holding unit 12.

  Here, when the pressure contact state is changed to the pressure release state (when the pressure contact is released), the first upper holding body 111 and the first lower holding body 112 (the second upper holding body 121 and the second holding body) are pressed by the biasing member 15. The same applies to the lower holding body 122). However, as shown in FIG. 4, there is almost no clearance between the flat conductor holding grooves 111A, 112A, 121A, 122A and the first flat conductor C1 and the second flat conductor C2, and the plasticity of the metal due to the pressing. Part of the metal that has flowed due to the deformation (expanded joint surface) enters a slight clearance (for example, a corner portion of the groove) of the flat conductor holding grooves 111A, 112A, 121A, 122A to increase the adhesion, and the biasing member 15 The first upper holding body 111 and the first lower holding body 112 (the same applies to the second upper holding body 121 and the second lower holding body 122) may not be able to be separated by only the urging force.

  Therefore, in the present embodiment, in the pressure released state (FIG. 3B), in addition to the urging force of the urging member 15, the first holding portion (the first upper holding body 111 and the first lower holding body 112) is moved. The X-direction is moved away from the second holding portion 12 to return to the first X-direction release position, and the second holding portions (the second upper holding body 121 and the second lower holding body 122) are moved in the X direction. The first X-direction release position is returned to the second X-direction release position by moving in the direction away from the first holding unit 11 along the direction.

  Even when the first holding unit 11 and the second holding unit 12 are forcibly moved in the direction of separating in addition to the urging member 15, the first rectangular conductor C 1 and the first rectangular conductor C 1 are moved by a movement restricting unit (not shown). The movement of the second rectangular conductor C2 in the direction of separating from each other along the X direction is restricted.

  In the retracted state, the first holding portion 11 and the second holding portion 12 that are in the pressure contact state, the pressure release state, or the clamping state are moved to the X direction separation position along the X direction, and the first upper holding body 111 and the first 1 The lower holding body 112 is moved along the Y direction and moved to the Y direction separation position, and the second upper holding body 121 and the second lower holding body 122 are moved along the Y direction to the Y direction separation position. Move (FIG. 2 (a)).

  Although the cold pressure welding apparatus 10 can perform cold pressure welding with a single press between the rectangular conductors, it is desirable to repeatedly press a plurality of times for one joint portion in order to stabilize the joint surface. As an example, the amount of pressing (compression amount) per time of the cold welding apparatus 10 is about 0.5 mm for both the first flat conductor C1 and the second flat conductor C2. Then, when one part is repeatedly pressed 3-4 times (cold pressure welding) and compressed by about 1 mm or more (preferably about 1.5 mm or more, specifically about 2 mm), stable joining is achieved. A surface is obtained.

  For this reason, the cold pressure welding apparatus 10 of this embodiment repeats the clamping state, the pressure welding state, and the pressure welding released state, and cold-welds the first rectangular conductor C1 and the second rectangular conductor C2.

  As shown in FIG. 3A, when the first holding part 11 and the second holding part 12 are moved to the close position after the clamping state, the end faces of the first rectangular conductor C1 and the second rectangular conductor C2 are in contact with each other. After contact (contact), the end faces are pressed and cold-welded. Since the first holding unit 11 and the second holding unit 12 that are in the close position do not approach each other any more, the first holding unit 11 and the second holding unit 11 are temporarily shifted to the press-contact release state (FIG. 3B). The holding unit 12 is moved to the Y direction release position to release the holding of the rectangular conductor, and the first holding unit 11 and the second holding unit are moved to the X direction release position. Then, the first holding conductor 11 holds the first flat conductor C1 so that the predetermined protruding amount A1 protrudes after the transition to the clamping state, and the second holding portion 12 causes the second holding portion 12 to protrude. By holding the single rectangular conductor C2 and making a transition to the pressure contact state again, a plurality of pressings can be repeated for one joint portion.

  That is, the X-direction release position is a position where the first holding part 11 can project and hold the first flat conductor C1 with the protruding amount A1, and the second holding part 12 protrudes the second flat conductor C2. It is a position that can be protruded and clamped by the amount A2.

  Note that the X-direction release position does not have to be a position where each of the flat conductors protrudes with the protruding amounts A1 and A2 when the state is subsequently changed to the holding state (while remaining in that position). In that case, in the clamping state, the first holding part 11 and the second holding part 12 may be moved and held to positions where the flat conductors protrude with the protruding amounts A1 and A2.

  In the above embodiment, the first holding unit 11 and the second holding unit 12 are stopped at the X direction release position and the Y direction release position in the press release state, but the X direction release position and Although the Y-direction release position passes, it may not stop at the position. That is, the first upper holding body 111 and the first lower holding body 112 (the same applies to the second upper holding body 121 and the second lower holding body 122) are not between the holding position, the Y-direction release position, and the Y-direction separation position. The first holding unit 11 and the second holding unit 12 may move without stopping between the proximity position, the X direction release position, and the X direction separation position. .

  Conventionally, cold welding has been used to join round wires, but according to the cold welding apparatus 10 of the present embodiment described above, good and stable cold welding of rectangular conductors can be performed. Can do.

  Moreover, the cold pressure welding apparatus 10 can be utilized as the coil manufacturing apparatus 20 by using a coil piece as a rectangular conductor (the 1st rectangular conductor C1, the 2nd rectangular conductor C2). This will be described below.

<Coil manufacturing equipment>
<Coil manufacturing equipment / flat rectangular conductor (coil piece)>
First, the rectangular conductor C used in the coil manufacturing apparatus 20 of this embodiment will be described with reference to FIG. FIG. 5 is a top view of the wide surface WS of the flat conductor C. FIG. The flat conductor C is a plurality of strip-shaped flat conductors that have a straight line shape (FIG. (A)) or at least one bent portion (FIG. (B) to (e)), and can be spiral when continuous. These are hereinafter referred to as coil pieces. The coil pieces having the bent portions are bent in the same direction in the longitudinal direction of the band so as to form a spiral shape when they are continuous. In the case of a coil piece having a bent portion, the bent portion is preferably at least one non-curved (for example, substantially right angle) shape.

  Further, in the following description, a helical structure in which a plurality of coil pieces (flat rectangular conductors) are continuous (connected), and the coil structure includes a helical structure before completion as a coil (spiral structure to be completed). Shall be. That is, in the following description, the coil piece (flat conductor) is a linear piece or a minimum unit coil piece having a bent portion in the same direction in the longitudinal direction of the belt 1 to 4, and a plurality of the minimum unit coil pieces. And a coil piece formed with a spiral structure of one or more rounds of a coil (spiral structure to be completed). In addition, for convenience of explanation, when these distinctions are necessary, the minimum unit coil piece is called a unit coil piece, and a plurality of unit coil pieces are connected and completed as a coil (spiral structure to be completed). The coil piece before the schedule is called a bonded coil piece, and the helical structure that is scheduled to be completed (completed state) is called a coil. Further, it is assumed that the plurality of coil pieces have substantially the same cross-sectional shape and area perpendicular to the longitudinal direction of the band.

  As shown in the figure, the unit coil piece C0 is formed into a shape having a straight or a substantially non-curved bent portion (corner) by punching a copper plate (for example, 1 mm thick) as an example. The That is, the unit coil piece C0 has a straight shape (I-shape) without a bent portion in the top view of the wide surface WS (FIG. 1A), and an L-shape with one bent portion (FIG. 1B). U-shaped (U-shaped) having two bent portions (FIG. (C)), substantially C-shaped having three bent portions (FIG. (D)), having four bent portions, the same C-shaped (substantially O-shaped (substantially B-shaped)) (the same figure (e)). In the following description, U-shaped, (substantially) C-shaped, substantially O-shaped In any case, it is assumed that the bent portion (corner portion) has a substantially right-angled shape.

  A plurality of coil pieces (unit coil pieces and / or bonded coil pieces) have a preparation length L0 which is the total distance in the longitudinal direction of the band, and is completed in the longitudinal direction of the spiral structure (coil) to be completed. It is set to be longer than the length by a margin. The margin is set to a shortened total distance that is shortened by pressing when all of the plurality of coil pieces are cold-welded. The preparation length L0, the completed length, the margin, and the total shortened distance will be described in detail in the description of the coil manufacturing method described later.

<Coil manufacturing device / holding unit>
The coil manufacturing apparatus 20 of the present embodiment is an example of use of the cold welding apparatus 10 described above, and therefore, the same configuration as that of the cold welding apparatus 10 is denoted by the same reference numerals, and redundant description is omitted. A configuration suitable for use in the coil manufacturing apparatus 20 will be mainly described.

  Referring again to FIG. 1, the coil manufacturing apparatus 20 includes a first holding unit 11 and a second holding unit 12 that are capable of holding a flat conductor and another flat conductor and are disposed to face each other. A plurality of flat rectangular conductors (coil pieces) that can be spiraled when continuous are formed to form a helical structure that becomes a coil. The preparation length to be the distance is set to be longer than the completed length in the spiral longitudinal direction of the spiral structure to be completed, and the end faces of a plurality of flat conductors (coil pieces) are banded together. Press along the longitudinal direction and cold-weld while shortening the distance in the longitudinal direction of the strip, and set the total shortened distance to shorten all of the multiple rectangular conductors (coil pieces) by cold-welding. In which a spiral structure is formed A.

  That is, in the coil manufacturing apparatus of the present embodiment, the length of the coil piece (joining coil piece) held by the first holding part 11 or the second holding part 12 becomes longer as the number of coil pieces added (number of times of joining) increases. Therefore, the configurations of the first holding unit 11 and the second holding unit 12 are suitable for use in coil manufacturing.

  First, FIG. 6 is a schematic view of a coil piece being manufactured by the coil manufacturing apparatus 20. The figure (a) is a schematic diagram (top view) of the prepared unit coil pieces, and the figures (b) to (d) are development views of the unit coil pieces and joining coil pieces in the middle of manufacture. FIG. (E) is a view in the direction of arrow V in FIG.

  Here, as an example, a plurality (four in this case) of U-shaped (U-shaped) unit coil pieces C0 having two bent portions are prepared and connected (continuously) to form a spiral shape of two rounds. The case where the coil (helical structure) 50 which consists of is manufactured is shown as an example. The two-dot chain lines at both ends of the coil pieces in FIGS. 4B to 4D indicate the finished end of the completed coil. In this example, the finished end does not change (finished in the horizontal direction shown in the figure). It is assumed that the end position does not move.

  First, in the first cold welding, as shown in FIG. 2B, one end surfaces (indicated by circles) of the two unit coil pieces C01 and C02 are connected to form a joined coil piece CC1. In the next cold welding, one end face of the joining coil piece CC1 (one of the end faces where the unit coil pieces C01 and C02 are not joined) and the unit coil piece C03 are cold-welded, and the joining coil piece CC2 is formed ((c) in the figure), and in the next cold welding, one end face of the joined coil piece CC2 (one of the end faces where the unit coil pieces C01 and C03 are not joined) and the unit coil piece C04 is cold-welded to complete the coil 50 (FIG. 4D).

  That is, the first holding unit 11 or the second holding unit 12 holds the bent (here, U-shaped (U-shaped)) coil pieces, and the spirally joined coil pieces CC1, CC2,. Is present in the vicinity of the first holding unit 11 or the second holding unit 12, the first holding unit 11 and the second holding unit 12 need to be configured to avoid interference with these coil pieces.

  FIG. 7 is a diagram illustrating the configuration of the first holding unit 11, and FIG. 7A illustrates one unit coil piece C0 as the first holding unit 11 (first upper holding body 111 and first lower holding body). 112) is a diagram illustrating a state of being held, and is a diagram in which the facing surface OS2 facing the second holding unit 12 is viewed from the front. FIG. 4B is a front view of the coil 50 in a completed state as viewed from the axial center direction of the spiral structure, and the coil piece in FIG. 4A is a cross-sectional view taken along the line BB in FIG. Corresponds to the figure. The first holding unit 11 will be described here, but the same applies to the second holding unit 12. Moreover, the figure (c) is a front view of the 1st holding | maintenance part 11 (AA sectional view taken on the line AA of the figure (a)).

  As shown in FIGS. 4A and 4B, when the coil piece has two or more bent portions (for example, a U-shaped (U-shaped) coil piece), the first holding portion 11 and the joint In a region other than the coil piece (FIG. 2A), the coil piece C0 ′ extending from the U-turn from the coil piece C0 held by the first holding unit 11 may interfere. In this embodiment, in order to avoid this, the dimension of the 1st holding | maintenance part 11 and a coil piece (coil 50 to be completed) is set as the structure satisfy | filling the following relationship.

  That is, when connecting a U-shaped (U-shaped) coil piece, one end surface 111S of the first holding portion 11, specifically, one end surface 111S of the first upper holding body 111, and the same surface as this. The end surface of the first lower holding body 112 that is configured with one end face 112S of the first lower holding body 112, and the end face orthogonal to the facing surface OS2 is an internal space of the spiral structure (the space that is planned to be the internal space of the spiral structure is also (Hereinafter, this end face is referred to as a spiral inner end face IS). The spiral inner end surface IS is, for example, the front surface of the first holding unit 11 close to the worker.

  Therefore, in order to avoid interference between the first holding part 11 and the coil piece, it is necessary to provide the rectangular conductor holding grooves 111A and 112A of the first holding part 11 at appropriate positions, and from the spiral inner end surface IS, The distance d1 to the ends (upper end in the figure) of the rectangular conductor holding grooves 111A and 112A is a spiral along the third direction (Z direction in the figure: the band width direction of the coil piece performing cold welding). It is assumed that it is smaller than the distance D1 of the internal space of the structure (coil 50).

  Further, the length d4 in the X direction of the first holding part 11 (FIG. (C)) is smaller than the distance D2 (in the same figure (b)) of the internal space of the spiral structure (coil 50) along the X direction. Shall.

  In addition, after the two coil pieces are cold-welded, a burr 55 due to extrusion is generated at the connection portion. Therefore, after the cold pressure welding is completed, the coil piece (joined coil piece) is taken out from the first holding part 11 and the second holding part 12 and deburred, and the coil piece (joined coil piece) and the other (new) are removed. Cold-welded between the coil pieces.

  FIG. 8 is a view corresponding to FIG. 7A (seen from the same direction), and shows a state in which the joined coil piece CC is formed. In the coil manufacturing apparatus 20 of the present embodiment, the bonded coil pieces CC are formed on one side of the first holding unit 11 (the same applies to the second holding unit 12), here, on the first lower holding body 112 side. On the other hand, since the flat rectangular conductor holding grooves 111A and 112A of the first holding part 11 are linear grooves along the X direction, only a part of the linear shape including one end face of the joined coil piece CC at the time of cold welding. Is held by the first holding unit 11. Therefore, in order to avoid interference between the joined coil piece CC and the first holding portion 11 (first lower holding body 112), the coil piece (here, the joined coil piece CC) is spirally left in the vicinity of the end face where it is cold-welded. Cold-welding is performed between the coil pieces held by the second holding unit 12 while being elastically deformed and / or plastically deformed so as to spread in the spiral direction of the structure (direction along the Y direction).

  The deformation amount D3 of the elastic deformation and / or plastic deformation in the spiral traveling direction of the coil piece (here, the joined coil piece CC) is set to an amount that avoids interference between the first holding portion 11 and the coil piece. In other words, the length (thickness) d5 along the Y direction of the holding body (here, the first lower holding body 112) on the side on which the bonded coil piece of the first holding unit 11 is formed is the coil piece (here, bonded). It is assumed that the amount of deformation D3 allowed for elastic deformation and / or plastic deformation of the coil piece CC) in the spiral traveling direction is smaller.

  Thus, the coil manufacturing apparatus 20 of this embodiment forms a helical structure by joining the coil pieces by cold pressure welding while elastically deforming and / or plastically deforming the coil pieces in the spiral traveling direction (direction along the Y direction). is there. In this way, during manufacture, the coil pieces are connected (added) in a state of spreading in the traveling direction of the spiral, but after the spiral structure is completed, the spiral structure is integrally molded (for example, The coil 50 in which each circumference of the spiral is in close contact is formed by performing elastic deformation and / or plastic deformation that compresses in the traveling direction of the spiral.

  The coil manufacturing apparatus 20 according to the present embodiment uses a coil piece that is longer by a compression amount (shrinkage amount) by cold compression (longer margin) based on the length after completion of the coil, and is compressed by cold compression (longer margin). A coil having a desired length L is manufactured by adding coil pieces while repeating (shrinkage).

  Therefore, during the cold welding, the cold welding is performed while measuring the distance in the longitudinal direction of the coil piece. The distance in the longitudinal direction of the band is measured by, for example, providing a slip detection mechanism (not shown) in the first holding unit 11 and the second holding unit 12 (or in the vicinity thereof) to thereby hold the coil piece held by the first holding unit 11 By detecting slippage when the coil piece (second coil piece) held by the (first coil piece) and the second holding part 12 is pressed, the distance in the longitudinal direction of the band can be measured. The distance in the longitudinal direction of the belt may be measured simultaneously with the cold welding (in real time) or before and after the cold welding (or before or after the cold welding). Thereby, the high precision of the coil dimension after completion is realizable.

  As shown in FIG. 7B, the substantially right-angled bent portion of the coil piece becomes a corner portion of the coil 50. That is, according to the coil manufacturing apparatus 20 of the present embodiment, the corners on the inner peripheral side and the outer peripheral side are substantially perpendicular by joining together the coil pieces configured to have substantially right-angled bent portions by punching or the like. Coil 50 can be manufactured. Conventionally, a coil with a rectangular conductor has been manufactured by winding a long rectangular conductor. However, it is inevitable that at least the corners on the inner circumference side of the coil will have a curved shape in the winding. There were limits to improvements in heat dissipation and heat dissipation.

  However, according to the coil manufacturing apparatus of this embodiment, since the shapes formed by punching can be joined together, a right-angle (substantially right-angle) corner can be realized on the coil inner peripheral side, and the space factor is improved. In addition, it is possible to manufacture a coil that can improve heat dissipation by eliminating the extra space.

  In particular, the joint portion CP is provided in the straight portion avoiding the bent portion (corner portion). That is, pressure welding is performed using the linear portion of the coil piece. As a result, it is possible to improve the shape accuracy of the bent portion, and for example, it is possible to maintain the corner portion that is formed at a right angle (substantially right angle) in the punching process.

<Coil manufacturing method>
Next, the coil manufacturing method of this embodiment is demonstrated. The coil manufacturing method of this embodiment can be implemented in the above-described coil manufacturing apparatus 20, for example.

  That is, the coil manufacturing method according to the present embodiment prepares a plurality of strip-shaped flat conductors (coil pieces) that can form a spiral structure when continuous, and provides a total distance in the longitudinal direction of the plurality of flat conductors (coil pieces). The length L0 is set to be longer than the completed length L in the helical longitudinal direction of the helical structure (coil) to be completed by a margin M, and the end faces of the plurality of rectangular conductors (coil pieces) are connected to each other. By pressing along the longitudinal direction of the belt and performing cold welding while shortening the distance in the longitudinal direction of the belt, the shortened total distance S for shortening all of the plurality of rectangular conductors (coil pieces) by cold welding is set to an allowance M. By setting, a plurality of flat conductors (coil pieces) are joined together to form a helical structure (coil).

  Specifically, referring to FIG. 9, four U-shaped (U-shaped) unit coil pieces C0 having two bent portions (C01 to C04) are prepared and connected (continuously). A case where a coil (helical structure) 50 having a spiral shape with two rounds is manufactured will be described as an example. 6A is a top view of the coil pieces C01 to C04, FIG. 6B to FIG. 6D are development views of the connecting coil pieces, and a broken line in FIG. The axial center (center of the joint portion CP) of the helical structure of the coil 50 is shown. In addition, the two-dot chain lines at both ends of the coil pieces in FIGS. 4B to 4D indicate the finished end of the completed coil. In this example, the finished end does not change (in the horizontal direction shown in the drawing). It is assumed that the position of the finished edge does not move.

  Assuming that the lengths of the unit coil pieces C01 to C04 in the longitudinal direction of the belt are L01 to L04, respectively, the preparation length L0 that is the total distance in the longitudinal direction of the belt is L01 + L02 + L03 + L04. The preparation length L0 is set longer than the completed length L of the coil 50 in the spiral longitudinal direction by a margin M (L0 = L + M). When the unit coil piece C01 and the unit coil piece C02 are pressed along the longitudinal direction of the belt and subjected to cold pressure welding, the unit coil piece C01 is compressed to a length L01 ′ in the longitudinal direction of the band by the press (shortening ( The compression amount is the length of the distance S1 from the center of the joint CP), and the unit coil piece C02 is compressed to the length L02 ′ in the longitudinal direction of the band L02 ′ (the (shortening (compression) amount is the distance S2 from the center of the joint CP). The joined coil piece CC1 (length LC1) is formed (length (b)), and the end face of the joined coil piece CC1 (the end face on the unjoined side of the unit coil piece C01 or C02). When the unit coil piece C03 is cold-welded, the unit coil piece C03 is compressed to L03 ′ by these pressings (the amount of shortening (compression) is the length of the distance S3 from the center of the joint CP), and the joint coil piece CC1 is , C1 ′ is compressed (the amount of shortening (compression) is the length of the distance S4 from the center of the joint portion CP) to form the joined coil piece CC2 (FIG. 5C). When the unit coil pieces C01 and C03 are joined to the unit coil piece C04 by cold pressure welding, the unit coil pieces C04 are compressed to L04 'by these pressings (the amount of shortening (compression) is reduced at the joining portion). The length of the distance S5 from the center of the CP), and the joined coil piece CC2 is compressed to LC2 ′ (the amount of shortening (compression) is the length of the distance S6 from the center of the joint CP), and the completed length in the spiral longitudinal direction (starting point) The coil 50 (helical structure) having a length L from ST to the end point SE is completed ((d) in the figure) The coil piece (unit coil piece and / or joined coil piece) is joined to complete the coil 50. Until the coil piece is short The sum of the amounts (shortened total distance S = S1 + S2 + S3 + S4 + S5 + S6) corresponds to the margin M.

  The manufacturing method of the coil of this embodiment is demonstrated anew along a time series. First, based on the length L of the coil 50 in the completed state, the lengths L01 to L04 of the unit coil pieces are set so that the total shortened distance S = the margin M, and the compression amount S1 to S1 by cold welding is set. S6 is set.

  Then, using the coil pieces set in this way, the end faces of the unit coil piece C01 and the unit coil piece C02 are pressed by the set compression amounts S1 and S2 and added by cold welding to form a joined coil piece CC1. To do. The compression amounts S1 and S2 at this time are grasped by measuring the distance in the longitudinal direction of the two coil pieces by detecting the slip when the unit coil piece C01 and the unit coil piece C02 are pressed. The method of grasping the amount of compression is the same in the following cold welding.

  After cold-welding one joining region (for example, near the end surface where the unit coil piece C01 and the unit coil piece C02 are joined), burrs are generated by pressing into the joint, so that the burr is removed after cold-welding. I do.

  Next, the spiral traveling direction of the helical structure to be completed, leaving the vicinity of the end face (end face where the unit coil piece C01 or unit coil piece C02 is not joined) where the coil piece (joined coil piece CC1) is cold-welded. While being elastically deformed and / or plastically deformed, cold welding is performed with another coil piece (unit coil piece C03). At this time, the deformation amount of the elastic deformation and / or plastic deformation in the spiral traveling direction of the bonding coil piece CC1 includes the first holding part 11 and the second holding part 12 that hold the coil piece during cold pressure welding, and the bonding coil piece. The amount is set to avoid interference with CC1. The deformation amount is the same in the following cold pressure welding.

  Thereafter, the coil pieces are added in the same manner. That is, the end face of the joined coil piece CC1 (the end face on the side where the unit coil piece C01 or C02 is not joined) and the unit coil piece C03 are pressed by the set compression amounts S3 and S4 and added by cold welding, and joined. The coil piece CC2 is formed. Thereafter, the debonding of the joining region is performed, and the joining coil piece CC2 is elastically deformed and / or plastically deformed in the spiral traveling direction of the spiral structure to be completed, leaving the vicinity of the end face to be cold-welded. The end face of CC2 and the unit coil piece C04 are pressed by the set compression amounts S5 and S6 and added by cold pressure welding to obtain a completed spiral structure.

  FIG. 10 is a diagram illustrating an example of a completed spiral structure 50 ′ (the number of turns of the coil is different from that of the above-described embodiment). Fig. 10 (a) is a front view seen from the direction of the spiral axis, Fig. 10 (b) is an arrow view (side view) in the V direction before molding, and Fig. 10 (c) and (d) are after molding. FIG.

  The completed spiral structure 50 ′ is formed by press working or the like. That is, during cold welding, in order to avoid buffering with the first holding unit 11 and the second holding unit 12, elastic deformation and / or plastic deformation in the spiral traveling direction of the helical structure can be performed. Since an unnecessary and non-uniform spread (space) is formed in the spiral structure, it is elastically deformed and / or plastically deformed in the spiral direction of the spiral structure so as to compress it, and each circumference of the spiral is made as much as possible to each other. Close (close) (FIG. (C)).

  Further, if necessary, in accordance with the shape of the stator core, it is concave or convex in the axial center direction of the helical structure (the radial direction of the stator core), that is, as shown in FIG. The peripheral end is formed into a curved shape that is not flush with the outer peripheral end.

  Thereafter, the molded spiral structure is immersed in a liquid insulating resin and integrally covered with the insulating resin. In addition, you may coat | cover with an insulating resin integrally by spraying a liquid insulating resin to the helical structure after shaping | molding. Conventionally, a long conducting wire corresponding to the completed length of a coil is coated with an insulating resin, and then wound to form a spiral structure. However, in this case, the insulating resin is stretched near the outer periphery of the curved portion of the winding, and the coating thickness is reduced, which causes deterioration of the pressure resistance. Further, for example, when coating with an insulating resin before the above molding, the same problem occurs because the coating thickness of the insulating resin varies depending on the press. In this embodiment, since the helical structure molded into a shape attached to the stator core is integrally covered with the insulating resin after molding, the uniformity of the insulating resin film thickness can be improved. Moreover, since it coat | covers with an insulating resin integrally after shaping | molding, helical structures can be adhere | attached with an insulating resin, and it can coat | cover with a uniform film thickness.

<Modification of coil piece>
FIG. 11 is a diagram illustrating a connection example when the coil pieces have different shapes.

  The figure (a) is a top view which shows the example of a connection by an L-shaped coil piece, Here, the case where the connection coil piece for one round is comprised using four L-shaped coil pieces C0. Show. Although illustration is omitted for convenience of explanation, in this case as well, each coil piece has a preparation length L0 that is the total distance in the longitudinal direction of the band, and the completed length in the longitudinal direction of the spiral structure (coil) to be completed. It is set to be longer than the length L by a margin M. The margin M is set to a shortened total distance S that is shortened by pressing when all of the plurality of coil pieces are cold-welded.

  In addition, it is not necessary to configure all the connection coil pieces for one round with the same shape (L-shape). That is, it is good also as a connection coil piece for 1 round by combining the I-shaped (straight line shape) or U-shaped (U-shaped) coil piece in L shape.

  FIG. 4B is a top view showing a connection example in which a C-shaped coil piece C0 and an I-shaped coil piece C1 are combined. Although illustration is omitted for convenience of explanation, in this case as well, each coil piece has a preparation length L0 that is the total distance in the longitudinal direction of the band, and the completed length in the longitudinal direction of the spiral structure (coil) to be completed. It is set to be longer than the length L by a margin M. The margin M is set to a shortened total distance S that is shortened by pressing when all of the plurality of coil pieces are cold-welded.

  Moreover, it is good also as a connection coil piece for 1 round by combining a substantially C-shaped coil piece with three corner | angular parts, and an L-shaped coil piece. Further, the coil pieces constituting the first and second turns of the spiral structure may be different combinations.

  FIG. 4C shows a U-shaped (U-shaped) coil piece C0 having two corners and a coil piece (O-shaped (b-shaped) coil for one round of the spiral structure to be completed. Piece) It is an expanded view in the case of forming a joined coil piece in combination with C1. The two-dot chain lines at both ends of the coil piece in the figure indicate the finished end of the completed coil. In this example, the finished end does not change (the position of the finished end does not move in the horizontal direction in the figure). ).

  The joint portion of the O-shaped coil piece C1 is cut. When one end of the U-shaped coil piece C0 and one end of the O-shaped coil piece C1 are cold-welded, the U-shaped coil piece C0 has a compression amount S0, and the O-shaped coil piece C1 has a compression amount S1. Once compressed, this can be repeated to form a helical structure. In FIG. 9, (when the same length U-shaped coil piece C0 is used), as shown in the figure, the joint portion CP is located at substantially the same position along the axial center of the helical structure on each circumference of the helical structure. In the case of FIG. 11C, the joint portion CP is formed at a position shifted by a predetermined amount along the axial center (broken line) of the spiral structure in each circumference of the spiral structure. The

<Coil modification>
FIG. 12 is a diagram illustrating a modification of the coil manufacturing apparatus and the coil manufacturing method. FIG. 11A is a schematic diagram of the coil manufacturing apparatus 20 ′, and FIG. 10B is a side view of the coil 50 manufactured thereby, corresponding to FIG. c) is a perspective view of the coil 50.

  The coil manufacturing apparatus 20 ′ includes a plurality of holding units 22 including the first holding unit 11 and the second holding unit 12, as shown in FIG. 5A, and the plurality of holding units 22 (22 </ b> A to 22 </ b> E) include Each of the first holding part 11 and the second holding part 12 has a different width W (width along the Z direction, width in the transverse direction BS of the rectangular conductor) of the rectangular conductor holding grooves 111A, 112A, 121A, 122A (sequentially). It may be larger (or smaller).

  As described above, by using the plurality of holding units 22 having different widths W of the rectangular conductor holding grooves 111A, 112A, 121A, and 122A, it is possible to join the rectangular conductors having different widths (widths WA to WE in the drawing). That is, while moving sequentially between the plurality of holding units 22, a cold structure is formed with a different holding unit 22 for each circumference of the helical structure, thereby forming a helical structure having a different length for each circumference of the coil. it can. That is, using U-shaped (U-shaped) unit coil pieces having the same length in the longitudinal direction of the belt, the coil pieces are joined by cold pressure welding while sequentially moving between the plurality of holding units 22. Thus, the coil 50 (FIGS. 5B and 5C) having a quadrangular frustum outer shape can be formed.

  A plurality of holding units 22 having different depths d3 of the flat conductor holding grooves 111A, 112A, 121A, and 122A may be used. In that case, the plate thickness of each circumference of the spiral structure constituting the coil 50 can be varied.

<Coil>
Next, the coil of this embodiment will be described with reference to FIG. FIG. 13A is a front view seen from the axial center direction of the spiral structure, and FIG. 13B is a cross-sectional view taken along line AA of FIG. FIG. 3C is a side view of FIG.

  The coil 50 according to the present embodiment is composed of a spiral structure in which strip-shaped rectangular conductors (coil pieces) are continuous in a spiral shape, and as shown in FIG. Non-curved corners (substantially perpendicular corners) 50C are provided. Here, as an example, it is manufactured using the above-described coil manufacturing apparatus and coil manufacturing method.

  In a conventional coil constructed by winding a long rectangular conductor longer than one round of the spiral structure of a completed coil, it is inevitable that the bent portion becomes a curved structure, and when it is attached to the stator core A large space is generated. Since the heat retention effect is enhanced in the blank portion, there is a limit to the improvement in heat dissipation of the coil. Further, when a long flat conductor is wound after being coated with an insulating resin, there is a problem that the insulating resin coating thickness is reduced at the bent portion, and the pressure resistance deteriorates.

  On the other hand, since the coil 50 of this embodiment can form the shape for one round of the helical structure of a coil by stamping, it can form a coil of desired shape in front view. That is, the coil 50 having a shape that is infinitely close to the shape of the stator core (at least the inner peripheral corner portion 50C is a right angle or a substantially right angle) is obtained. Thereby, unlike the coil of a winding system, the space part between the stator core 60 (shown with a broken line in the figure (a)) can be minimized. For example, the length of the space portion (distance from the inner peripheral side of the coil 50 to the stator core 60) per side of the coil 50 can be reduced to 0.5 mm to 1.0 mm, thereby improving heat dissipation. In addition, since the insulating resin can be coated with increased uniformity over the entire coil 50, it is possible to suppress deterioration of the breakdown voltage due to variations in the thickness of the insulating resin.

  Further, in the coil 50 of the present embodiment, the width perpendicular to the spiral traveling direction of the spiral structure (the width W1 in the short side direction of the coil piece) is widened at the corner portion to become the width W2, and this also reduces the coil resistance. can do.

  Furthermore, since the cold welding is a metal atomic bond, the connecting portion is reliably bonded to such an extent that it cannot be visually recognized. As a result, the stability of the connection portion can be significantly improved as compared with a configuration in which a coil for one turn (or less) is connected in a plane with an adhesive (adhesive, brazing, etc.).

  Further, as shown in FIG. 5B, the first circumference of the spiral of the helical structure (for example, the first circumference by the joined coil piece CC1) is partially formed and the flat conductor (coil piece) of the other part is formed. A first thin portion T1 having a plate thickness D8 thinner than the plate thickness D7 is provided. Further, the second circumference (for example, the second circumference by the joined coil piece CC2) that is continuous with the first circumference is partially in the plate thickness D8 than the plate thickness D7 of the flat conductor (coil piece) of the other portion. A thin second thin portion T2 is provided.

  As described above, the coil pieces are sandwiched by the first holding part 11 and the second holding part 12 of the coil manufacturing apparatus 20 during the cold pressure welding, but at this time, the total depth of the rectangular conductor holding grooves 111A and 112A ( The total depth of the rectangular conductor holding grooves 121A and 122A is also smaller than the plate thickness D7 of the coil piece. Then, when the coil piece is pressed by the pressing portion 18 and is held between the first holding portion 11 and the second holding portion 12, the holding portions are formed by the flat conductor holding grooves 121A and 122A and the flat conductor holding grooves 111A and 112A. Compressed in the plate thickness direction to a thickness (D8) comparable to the total depth. The sandwiched portions between the first holding part 11 and the second holding part 12 are the first thin part T1 and the second thin part T2. That is, the first thin portion T1 and the second thin portion T2 are formed corresponding to the cold-welded joint portion CP. For example, a U-shaped (U-shaped) coil piece is connected. In the case of the coil, the first thin portion T1 is provided at two locations on the first circumference, and the second thin portion T2 is also provided at two locations on the second circumference. Further, when the lengths of the U-shaped unit coil pieces are all the same, the first thin portion T1 and the second thin portion T2 are overlapped in the axial center direction of the spiral structure as indicated by a broken-line square. Is provided.

  Further, as shown in FIG. 11, the first thin portion T1 and the second thin portion T2 formed corresponding to the cold welded joint portion CP have U-shaped (U-shaped) and O-shaped coil pieces as shown in FIG. In the case of being configured with a combination of (b-shaped), it is formed at a position that is alternately displaced on the first circumference and the second circumference corresponding to the joint portion CP (in the case of an O-shaped coil piece) A thin part is formed only at one place in one turn).

  The coil 50 is integrally covered with an insulating resin on the entire circumference of the spiral structure. Thereby, the adhesiveness of each periphery of a helical structure can be improved. In addition, a gap portion SP of the coil piece is formed between the first thin portion T1 and the second thin portion T2, and a part of the insulating resin is also embedded in the gap portion SP. That is, as described in the above-described manufacturing method, the insulating resin enters the gap portion SP in order to immerse the helical structure in the liquid insulating resin after completion of the helical structure (molding as necessary). Thereby, the adhesiveness of each periphery of a spiral structure can be improved further.

  Further, the coil 50 is formed in a concave or convex shape in the axial center direction of the helical structure (the radial direction of the stator core) according to the shape of the stator core 60, that is, as shown in FIG. The peripheral end may be formed in a curved shape that is not flush with the outer peripheral end.

  FIG. 14 is a diagram in which the calorific values of the coil 50 of this embodiment and a coil (round wire coil) configured by winding a round wire are measured and compared. About the round wire coil and the coil 50 of this embodiment, the emitted-heat amount (temperature) with time passage was measured at 5V and 20A.

  The temperature of the round wire coil rapidly increased to 28.5 ° C. in 10 seconds from the start, 42 ° C. in 30 seconds, and increased to 73 ° C. in 90 seconds from the start, so the experiment was stopped. On the other hand, the coil 50 (20A) of this embodiment gradually rises in temperature to 21.1 ° C. in 10 seconds from the start and 21.5 ° C. in 30 seconds, and reaches saturation at 32.4 ° C. after 1530 seconds from the start. became.

  As is clear from this result, the coil 50 (coil with a substantially right angle on the inner circumference (inner circumference right angle coil)) 50 of the present embodiment has a temperature close to room temperature (for example, 40 ° C. to 50 ° C.) or higher even during operation. It can be said that there is almost no temperature rise, and that heat dissipation is very high. And by such high heat dissipation, coil resistance can be reduced significantly compared with the past.

  Further, the width W3 of the start end portion and the end end portion of the spiral structure of the coil 50 may be wider than the width W1 in the band width direction. Thereby, like the corner portion, the coil resistance at the start end portion and the end end portion can be reduced.

  In addition, in this embodiment, the coil 50 of the inner periphery right angle | corner which formed the end surfaces of the coil pieces by joining repeatedly by cold pressure welding was demonstrated. However, the present invention is not limited to this, and the end faces of the coil pieces may be joined by other joining methods. Specifically, various connection methods such as ultrasonic welding (high frequency welding), electric welding, and brazing can be employed.

<Mounting method to stator core>
With reference to FIG. 15, the example of attachment to the stator core of the coil 50 of this embodiment is demonstrated. FIG. 15A is a side view of the coil 50 and the cassettes 51A and 51B. FIG. 15B is a cross-sectional view taken along the line cc in FIG. FIG. 15C is a cross-sectional view corresponding to a cross section taken along the line cc of FIG. 15A showing an example of attachment to the stator core 60.

  The coil 50 of this embodiment is molded along the outer shape of the stator core as shown in FIG. 13C, and is integrally covered with an insulating resin after molding, and this is attached to the stator core by so-called retrofitting.

  Therefore, for example, as shown in FIG. 5A, two cassettes 51A and 51B having flanges 52A and 52B on one surface side in the axial center direction of the spiral structure of the coil 50 are prepared. The coil 50 is inserted from the surface side where the flange portion 52A is not formed, and the other cassette 51B is overlapped to engage both. Then, the cassette-equipped coil 50 is inserted into the stator core 60. The cassettes 51 </ b> A and 51 </ b> B are provided with notches or engaging portions 53 so as to fit in a top view of the cross section shown in FIG.

In addition, as shown in the same figure (c), the coil 50 may be attached to one cassette 51C having the flange portion 52B only on one surface side in the axial center direction of the spiral structure and attached to the stator core 60. In that case, in order to prevent the coil 50 from being removed from the stator core 60 by centrifugal force during operation (or unnecessary movement (vibration) is generated), the stator core 60 is provided with a notch 61, and the cassette-equipped coil 50 is connected to the stator core. After attaching to 60, it is good to fit with the retaining ring 62 which covers the upper part of the coil 50 with a cassette, and the notch 61 of the stator core 60. FIG.
<Coil spiral structure>
The spiral structure of the coil will be further described with reference to FIGS. 16 and 17. FIG. 16 is a side view of the coil 50 of the present embodiment, where FIG. 16A is a side view seen from the short side of one example, and FIG. 16B is seen from the long side thereof. It is a side view, the same figure (c) is a side view seen from the short side of other examples, the same figure (d) is a side view seen from the long side, the figure (e) These are the side views seen from the short side of another example. FIG. 17 is a modified example of FIGS. 16 (c) and 16 (e). FIGS. 17 (a) and 17 (c) are external perspective views, and FIGS. It is an arrow side view of (a) and (c).

  For example, when a plurality of U-shaped (U-shaped) unit coil pieces shown in FIG. 6 are connected to form a spiral structure, as shown in FIGS. During one round from the circumference TC1 to the second circumference TC2, the thickness of the unit coil piece is absorbed by gradually deforming along the spiral traveling direction, and this is repeated for each circumference.

  That is, strictly speaking, the coil 50 according to an example of the present embodiment is connected to the next coil piece while each coil piece is slightly inclined, as shown in FIGS. A helical structure is formed. Here, one side surface (the same figure (a)) of the short side of the coil 50 and one side surface (the same figure (b)) of the long side are shown, but the same applies to all four side surfaces of the coil 50. Tilt.

  In addition, the coil 50 of the present embodiment is not limited to the above structure, and may have a spiral structure as shown in FIGS.

  That is, as shown in FIG. 5C, the part of the first circumference TC1 of the spiral of the spiral structure is deformed so as to have a step B corresponding to the thickness of the coil piece along the spiral traveling direction. A part of the second circumference TC2 of the spiral is deformed so as to have a step B corresponding to the thickness of the coil piece along the spiral traveling direction, and this is repeated to form a spiral structure. Note that the step B is formed only on one side surface of the coil 50 (for example, one side surface on the short side), and on the second portion on the same portion, that is, on the step B on the first periphery. A step B is formed.

  Thus, since the thickness of the coil piece is absorbed by the step B formed on only one side surface, the other three side surfaces are each coil piece as shown in the side view on the long side in FIG. They are not inclined and are stacked substantially horizontally.

  According to such a configuration, the surface of the outermost coil can be flattened without the start end SE and end end EE of the coil 50 projecting. That is, in the spiral structure shown in FIGS. 6A and 6B, the surface of the coil 50 including the start end SE (the lower end surface shown) is the coil surface SF12 of the start end SE as shown in FIG. There is a step difference between the coil surface SF11 'and the opposite coil surface SF11' that circulates. Similarly, the surface (the upper end surface in the drawing) of the coil 50 including the end end EE is not flush with the coil surface SF22 ′ on the side facing the coil surface SF21 ′ of the end end EE. When the thickness of the coil piece is relatively thin, there is little problem even if such a step occurs. However, when the coil piece is thick, it is necessary to secure a space for this step when setting the cassette 51A, 51B as shown in FIG. There may also be a problem that the coil 50 rattles due to the gap.

  On the other hand, in the spiral structure shown in FIGS. 3C and 3D, the surface of the coil 50 including the start end SE (the lower end surface in the drawing) is the coil on the opposite side that circulates with the coil surface SF12 of the start end SE. The surface SF11 is (substantially) provided on the same surface, and the surface of the coil 50 (upper end surface in the drawing) including the end end EE is also (substantially) the same as the coil surface SF22 on the side facing the coil surface SF21 of the end end EE. Provided on the surface. As a result, the size of the outer shape of the coil 50 can be reduced, and the adhesion to the cassettes 51A and 51B can be improved.

  FIG. 4E shows another example in which the coil structure has the same spiral structure as that shown in FIG. The coil piece may have a cross-sectional (substantially) square shape having substantially the same width W and thickness d2 in the band width direction BS as shown in FIG. Thus, when the thickness d2 is larger than the width W, it is more preferable to employ a spiral structure in which a step B is provided on one side surface of the coil 50 as shown in FIG.

  FIG. 17 is a diagram illustrating another example of the present embodiment. As shown in the figure, all the coil pieces constituting the coil 50 (all coil pieces connected along the spiral traveling direction) have different widths W and thicknesses d2 in the band width direction BS. Also good. For example, in the coil 50 shown in the figure, a coil piece whose width d2 gradually decreases as the width W of each coil piece gradually increases (WA, WB...) From the start end SE to the end end EE. Connected.

  The configuration is not limited to this example, and only the width W of each coil piece may be different (change), or only the thickness d2 of each coil piece may be different (change).

  By doing in this way, the coil 50 of a desired square frustum can be manufactured. Further, as in this example, when a plurality of coil pieces having different thicknesses d2 are used, when a spiral structure as shown in FIG. 16A is employed, the coil piece thickness d2 at the start end SE and the end end EE. Due to this difference, there is also a difference in the step value of the coil surface on the outermost periphery (the uppermost outermost periphery and the lowermost outermost periphery in the figure). As a result, the outer size of the coil 50 becomes larger and the shape becomes non-uniform (asymmetric), so that it is necessary to secure an extra space in the cassettes 51A and 51B. In addition, there is a high possibility that steady attachment to the cassettes 51A and 51B becomes difficult. In such a case, the outermost coil surface is (substantially) flat even if the thickness d2 of each coil piece is different by using a spiral structure in which a step B is formed on one side surface of the coil 50. (Coil surfaces SF11 and SF12 can be made the same surface, and coil surfaces SF21 and SF22 can be made the same surface), so that the size of the coil outer shape 50 can be greatly reduced and the cassettes 51A and 51B can be mounted. The trouble at the time of installation can be avoided.

  In the above example, the case where the step B is provided on one side surface that is the short side of the coil 50 has been described as an example. However, the step B may be provided on one side surface that is the long side of the coil 50. The position to be provided can be selected as appropriate depending on the shape of the drawer of the start end SE and the end end EE.

  As described above, the present invention is not limited to the above-described embodiment, and can be configured in various embodiments. For example, the bent portion of the coil piece may be curved.

  One coil piece is not limited to a single copper plate formed by punching, but a plurality of thin rectangular conductors (for example, a rectangular conductor having a square cross-sectional shape in the longitudinal direction of the band as shown in FIG. 16E). ) May be arranged in parallel in the width direction of the coil. Further, a part of the coil may be formed by a coil piece formed by punching a single copper plate, and a part of the coil may be formed by a coil piece formed by parallel arrangement of thin rectangular conductors.

  The present invention can be used when manufacturing a coil device using a rectangular coil.

DESCRIPTION OF SYMBOLS 10 Cold welding apparatus 20 Coil manufacturing apparatus 11 1st holding part 12 2nd holding part 50 Coil

Claims (5)

A method for producing a coil, comprising preparing a plurality of strip-like flat conductors that can be spiral structures when continuous, and joining the end faces of a plurality of the flat conductors to form the spiral structure,
The spiral structure has a corner portion that is a region where the spiral traveling direction changes, and a straight portion,
A pressure-contacting step of abutting and pressing one end surface of the first flat conductor in the longitudinal direction of the band and one end surface of the second flat conductor in the longitudinal direction of the band in the region to be the linear portion ;
Removing the burrs protruding in the direction crossing the belt longitudinal direction and the belt short direction by pressing, and
A method for manufacturing a coil, characterized in that: After the removing step,
Having another pressure contact process in which the other end face of the second flat conductor in the longitudinal direction of the belt and the one end face of the third flat conductor in the longitudinal direction of the third face are pressed against each other in the region to be the linear portion ;
The method for manufacturing a coil according to claim 1. The removing step is performed after the other pressing step ,
After the removing step ,
Another pressure contact step of pressing the other end face of the third flat conductor in the longitudinal direction of the band and one end face of the fourth flat conductor in the longitudinal direction of the belt in the region to be the linear portion;
The manufacturing method of the coil of Claim 2 characterized by the above-mentioned. Covering the completed spiral structure integrally with a coating;
The method for manufacturing a coil according to any one of claims 1 to 3, wherein: The spiral structure has a first straight line portion extending in a first direction and a second straight line portion extending in a second direction in an area of one circumference,
The corner is a region connecting the first straight part and the second straight part,
In the pressure welding step, a bonding portion is formed in a region to be the first straight portion or the second straight portion,
The method for manufacturing a coil according to any one of claims 1 to 4, wherein:

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