JP2019091920A - Manufacturing method of coil - Google Patents

Abstract

To provide a manufacturing method of a coil using a flat rectangular conductor, which can improve a space factor and heat dissipation without causing characteristic degradation due to cutting and joining.SOLUTION: A manufacturing method of a coil includes a pressure welding step of preparing a plurality of strip-like flat conductors C that can form a spiral structure when being continuous, bonding end faces of the plurality of flat conductors C to form a spiral structure, and butting and pressing one end face of a first flat conductor C in the longitudinal direction of the strip and one end face of a second flat conductor C in the longitudinal direction of the strip, and a removing step of removing burr generated by the pressing.SELECTED DRAWING: Figure 9

Description

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

  Examples of a coil device in which a coil is disposed around a core (stator core) of a stator core (stator core) include electric devices such as a motor, a generator, a transformer, etc. In such a coil device, low loss In order to achieve miniaturization and miniaturization, it is important to improve the space factor of the coils in the core.

  Conventionally, a coil using a flat conductor (hereinafter referred to as a flat coil) has been known as a coil capable of improving the space factor in the core. The flat coil is also referred to as a flat wound (square wound) coil, a square (square) coil, an edgewise coil, etc., with respect to a coil wound with a round wire whose cross-sectional shape orthogonal to the longitudinal direction is substantially circular. Coil means a coil formed by winding a flat rectangular conductor whose cross-sectional shape orthogonal to the longitudinal direction is rectangular.

  Further, as a method of manufacturing a flat coil, there is known a method of winding a long flat rectangular conductive wire (square conductive wire) into a substantially rectangular shape (see, for example, Patent Document 1). Also known is a method in which a flat rectangular conductor (flat conductive material) having a length of one winding of a coil is laminated, and the upper end surface of the lower end and the lower end of the upper end are overlapped and repeated by bonding means to form a helical structure. (See, for example, Patent Document 2).

  Further, a cold pressure welding method is known as a method of connecting conductors.

Patent No. 3881520 JP 2005-130676 A

  However, in the method of winding a long flat wire in a substantially rectangular shape as in the technique described in Patent Document 1, the corner portions (both on the outer peripheral side and the inner peripheral side) are curved and rounded. Can not be avoided. Since the core is generally in the form of a prism having substantially square corners, when a rounded coil is disposed around the core, a space is created between the core and the coil. Since this space accumulates heat during operation of the coil device, the heat dissipation of the coil device is deteriorated, and there is a problem that the efficiency of the coil device can not be increased due to the increase of the coil resistance. In addition, there is a limit to the improvement of the space factor of the coil at the corner.

  In addition, since the outer periphery of the flat wire used for the coil is coated with the insulating resin in advance, if it is wound, the film becomes thin at the corners on the outer periphery due to bending, and the withstand voltage of the coil device decreases. there were.

  On the other hand, in the case of a method of laminating and joining flat rectangular conductors for one turn of a coil as in the technique described in Patent Document 2, it is possible not to bend corner portions, and the heat dissipation and space factor described above Problems can be avoided. However, although it is connected by the joining means, deterioration of the characteristics at the joint portion between the lower end upper surface and the upper end lower end surface can not be avoided as compared with the uncut portion, and the operation stabilization Problems remain in terms of

  Furthermore, although one method of connecting the conductors is known, the method of cold-welding the round conductors is known. However, the flat-wires are cold-welded with good improvement of the stability of the connection. It was difficult.

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

  The present invention solves the above-mentioned subject by the following means.

  The present invention is a method of manufacturing a coil, which prepares a plurality of strip-like flat conductors which can form a helical structure when continuous, and joins together the end faces of the plurality of flat conductors to form the helical structure. A pressing step of butting and pressing one end face of the flat conductor in the longitudinal direction of the strip and the end face of the second flat conductor in the longitudinal direction of the strip, and removing the burr generated by the pressing , And a method of manufacturing a coil.

  According to the present invention, it is possible to provide a method of manufacturing a coil using a flat rectangular conductor which can improve the space factor and improve the heat dissipation without causing characteristic deterioration due to cutting and joining.

(A) It is the external view (front view) which showed a part of structure of the cold pressure welding apparatus which concerns on this embodiment typically. (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 pressure welding apparatus which concerns on this embodiment. It is the external view (front view) which showed typically the holding | maintenance part of the cold pressure welding apparatus which concerns on this embodiment. It is the side view which showed typically the holding | maintenance part of the cold pressure welding apparatus which concerns on this embodiment. It is a top view which shows the flat angle conductor which concerns on this embodiment. It is a schematic diagram which shows the mode of the cold pressure welding of the flat angle conductor which concerns on this embodiment. It is a figure which shows the coil manufacturing apparatus which concerns on this embodiment, It is a side view of (a) holding | maintenance part, (b) It is a front view of a coil, It is a front view of (c) holding | maintenance part. It is a side view of a attaching part of a coil manufacturing device concerning this embodiment. It is a schematic diagram explaining the coil manufacturing method concerning this embodiment. It is a schematic diagram explaining the coil manufacturing method concerning 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 device concerning this embodiment, and a coil manufacturing method. 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 (a), (c) The same figure (a) FIG. It is a side view showing the spiral structure of the coil concerning this embodiment. It is a figure which shows the helical structure of the coil which concerns on this embodiment, and is a (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 device>
FIG. 1 is a view for explaining a cold pressure welding apparatus 10 according to the present embodiment, and FIG. 1 (a) is an external view (front view) partially schematically showing the structure of the cold pressure welding apparatus 10. FIG. 1 (b) is a top view of the flat conductor C, and FIG. 1 (c) is a cross-sectional view taken along the line AA of FIG. 1 (b).

  As shown in FIG. 6A, the cold welding apparatus 10 is an apparatus for cold welding two flat conductors C (C1, C2), and the first holding unit 11 and the second holding unit 12 Have. In addition, in the following description, as shown to the figure (b) (c), the flat conductor C means the strip | belt-shaped (tape-like) conductor comprised by the plane with respect to the round wire conductor. That is, the flat conductor is a strip-shaped member having two opposing wide surfaces WS and two opposing narrow surfaces WT, as shown in FIGS. The cross section orthogonal to the band longitudinal direction BL (the line A-A in the same figure (b)) means a rectangular or rounded rectangular conductor as shown in the figure (c). In the following description, as an example of the flat conductor, a flat rectangular conductor having a rectangular cross section orthogonal to the longitudinal direction of the strip 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 the cross-sectional view in the AA line cross section in FIG. It may be

  The first holding portion 11 is movable along the first direction (the longitudinal direction of the flat rectangular conductor; the X direction in FIG. 6A), and the first upper holding member 111 and the first lower holding member 112 Configured The first upper holding body 111 and the first lower holding body 112 are disposed 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 in the drawing is referred to as a first upper holding body 111, and the lower holding body in the drawing is referred to as a first lower holding body 112. Not only up and down. That is, FIG. 1A may be a top view of the cold pressure welding apparatus 10. In that case, the first upper holding body 111 is, for example, a holding body on the back side, and the first lower holding body 112 is, for example, the near side. It becomes the holding body of the side. The first upper support 111 may be, for example, a left support, and the first lower support 112 may be, for example, a right support.

  The first upper holding body 111 and the first lower holding body 112 are movable along the X direction, and the facing surface OS1 along the X direction is in the second direction (the thickness direction of the flat conductor; the same It can move so as to abut or separate from each other 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 unit 12 is disposed to face the first holding unit 11 so as to have an opposing surface OS2 along the second direction (hereinafter, referred to as the Y direction) with the first holding unit 11, The configuration is the same as that of the first holding unit 11. Accordingly, although the detailed description is omitted, the second holding unit 12 is movable along the X direction, and is configured of the second upper holding body 121 and the second lower holding body 122. The descriptions of “upper and lower” of the second upper holding body 121 and the second lower holding body 122 are also similar to those of the first holding portion 11.

  The second upper holding body 121 and the second lower holding body 122 are movable along the X direction, and are movable so that the facing surfaces OS1 abut or are separated from each other along the Y direction.

  Further, the first holding portion 11 and the second holding portion 12 are biased by a biasing member (for example, a coil spring) 15 in a direction in which they are separated from each other along the X direction. Although not shown, the first upper holding member 111 and the first lower holding member 112 are biased by a biasing member (for example, a coil spring) in a direction away from each other along the Y direction. 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 the movement restriction means (not shown). The first rectangular conductor C1 and the second rectangular conductor C2 can move in the direction approaching along the X direction, but the movement in the direction away from each other is restricted.

    Further, a pressing portion 18 is provided on the outer side in the Y direction of the first holding portion 11 and the second holding portion 12. The pressing portion 18 presses the first upper holding body 111 and the first lower holding body 112 so as to abut each other, and the second upper holding body 121 and the second lower holding body 122 abut each other. Press these.

  FIGS. 2 and 3 are front views of the first holding unit 11 and the second holding unit 12 extracted, and are diagrams showing the state of their movement.

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

  In the state shown in FIG. 6A, the facing 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 which estranges. Hereinafter, this position is referred to as a Y-direction separation position. Further, in this state, this position, which is a position at which the facing surfaces OS2 of the first holding portion 11 and the second holding portion 12 are most separated in the X direction, is hereinafter referred to as an X-direction separated position.

  The figure (b) of the figure is a state which moved to the position which opposing surface OS1 of the 1st upper holding body 111 and the 1st lower holding body 112 abuts from the state shown to the figure (a). In this state, the first holding portion 11 sandwiches the (wide surface WS) of the first rectangular conductor with the first upper holding body 111 and the first lower holding body 112, and the second holding portion 12 holds the second upper holding body 121. And the second lower holding body 122 sandwich (the wide surface WS of) the second flat conductor.

  The first holding portion 11 holds the first rectangular conductor C1 so as to protrude in the direction of the second holding portion 12 from the facing surface OS2 along the Y direction. Similarly, the second holding portion 12 holds the second flat rectangular conductor C2 so as to protrude in the direction of the first holding portion 11 from the facing surface OS2 along the Y direction. 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 at which the facing 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) abut on each other is referred to as a holding 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) are movable between the holding position and the Y-direction spaced position.

  Further, as shown in FIG. 6C, the release position (in the Y direction) of the hold is included between the hold 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 support 111 and the first lower support 112 (the second upper support 121 and the second lower support). The body 122) is at a position spaced apart.

  In addition, the position where opposing surface OS1 of the 1st upper holding body 111 and the 1st lower holding body 112 (the 2nd upper holding body 121 and the 2nd lower holding body 122) contacts from the Y direction cancellation position of the figure (c). It is also possible to move to the state shown in FIG.

  In FIG. 2, the positions of the first holding portion 11 and the second holding portion 12 along the X direction are both kept apart from each other in the X direction.

FIG. 3 is a view for explaining movement of the first holding unit 11 and the second holding unit 12 mainly along the X direction.
FIG. 3A is a position at which the first holding unit 11 and the second holding unit 12 are moved along the X direction so that the facing surface OS2 is closest to the state in FIG. 2B. Hereinafter, this position is called a proximity position. That is, the first holding unit 11 and the second holding unit 12 are movable between the X-direction separated position shown in FIG. 2 and the close position shown in FIG. 3 (a). Even in the proximity position, the first holding portion 11 and the second holding portion 12 do not abut on each other.

  The first holding portion 11 holds the first flat conductor C1 so as to protrude with a protrusion amount A, and the second holding portion 12 holds the second flat conductor C2 with a protrusion amount A2 for holding (( 2B, when the first holding portion 11 and the second holding portion 12 are in the close position, the first holding portion 11 and the second holding portion 12 do not abut, but the first flat conductor C1 and the second flat portion The flat conductors C2 abut (join) and further press 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 in the close position, they are slightly longer than the length abuts each other (an amount that can be pressed against each other after being abutted).

  Further, as shown in FIG. 2B, the release position (in the X direction) of the pressing is included between the proximity position and the X direction separation position (FIG. 2A). The release position in the X direction (hereinafter, the X direction release position) is a position at which the first holding portion 11 and the second holding portion 12 are separated at 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 separated and moved to the Y direction release position, and the second upper holding body 121 and the second lower holding body 122 are also separated and moved to the Y direction release position.

  In addition, it can also transition 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 (viewed in the direction of arrow V in FIG. 1) of the first holding portion 11 when the facing surface OS2 of the first holding portion 11 is viewed from the second holding portion 12 side. The figure (a) has shown the state (state of FIG. 2 (a)) in which the 1st upper holding body 111 and the 1st lower holding body 112 are in a Y direction separated position, and the figure (b) is a holding position. State of FIG. 2 (b)).

  In the first upper holding body 111, the rectangular conductor holding groove 111A is located at a position close to one end surface (right end surface in the figure) 111S in the third direction (band width direction of the rectangular conductor; Z direction in FIG. A flat rectangular conductor holding groove 112A is provided in the first lower holding body 112 at a position close to one end surface (right end surface in the figure) 112S in the third direction (hereinafter referred to as the Z direction). The third direction (Z direction) is a direction different from each of the X direction and the Y direction, and in this case, is a direction orthogonal to both.

  One end face 111S of the first upper holding body 111 and one end face 112S of the first lower holding body 112 are positioned on the same plane, and one end face in the third direction (Z direction) 1 refers to the front of the first upper holding body 111 and the first lower holding body 112, and refers to the end face near the worker.

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

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

  As shown to the figure (b), when opposing surface OS1 of the 1st upper holding body 111 and the 1st lower holding body 112 contact | abuts (when it exists in the clamping position (FIG. 2 (b)), a flat angle conductor The holding grooves 111A and 112A become one prismatic hole portion penetrating the first holding portion 11 in the X direction, and in the hole portion, the flat conductor (first flat conductor C1) is compressed in the plate thickness d2 direction It is in close contact with the rectangular conductor holding grooves 111A and 112A in a state (in a state where the plate thickness is reduced), and is held by the first holding portion 11 (the first upper holding body 111 and the first lower holding body 112).

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

  The first holding unit 11 and the second holding unit 12 are in any of a holding state, a pressure contact state and a pressure contact cancellation state, a withdrawal state, and a transition state between two of these states.

  Referring again to FIGS. 2 and 3, in the sandwiching state, the first upper holding body 111 and the first lower holding body 112 of the first holding portion 11 are separated from each other in the Y direction along the Y direction (FIG. (a)) to move to the holding position (FIG. 2 (b)) to hold the first flat conductor C1 between the first upper holding body 111 and the first lower holding body 112, and the second holding portion 12 The upper holding body 121 and the second lower holding body 122 are moved from the Y-direction spaced position (FIG. 2 (a)) to the holding position (FIG. 2 (b)) along the Y direction. The second flat rectangular conductor C <b> 2 is held by the second lower holding body 122.

  As described above, the first holding portion 11 holds the first rectangular conductor C1 so as to protrude from the facing surface OS2 along the Y direction by the protrusion amount A1 in the direction of the second holding portion 12, and the second holding portion 12 The second flat conductor C2 is held by being protruded from the facing surface OS2 along the Y direction by a protrusion amount A2 in the direction of the first holding portion 11.

  At this time, the pressing portion 18 (see FIG. 1A) presses them so that the first upper holding body 111 and the first lower holding body 112 abut, and the second upper holding body 121 and the second lower holding These are pressed so that the body 122 abuts. As a result, 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). The holding portion 11 and the second holding portion 12 sandwich the sheet (see FIG. 4).

  Further, in the holding state, the first upper holding body 111 and the first lower holding body 112 of the first holding portion 11 in the Y direction release position (FIG. 2C) are at the holding position (FIG. 2B). As it moves and causes the first upper holding body 111 and the first lower holding body 112 to sandwich the first flat conductor C1, the second upper side of the second holding portion 12 in the Y direction release position (FIG. 2C). Also when moving the holding body 121 and the second lower holding body 122 to the holding position (FIG. 2B) and holding 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 unit 18 presses the first upper holding body 111 and the first lower holding body 112 so that the first upper holding body 111 and the first lower holding body 112 abut each other, and the second upper holding body 121 and the second lower holding body 122 abut. Press these on. Thereby, the rectangular conductor holding grooves 111A, 112A, 121A, 122A and the like in the state where the first rectangular conductor C1 and the second rectangular conductor C2 are compressed in the thickness direction in the hole portion (the thickness is reduced). It adheres closely and is clamped by the 1st holding part 11 and the 2nd holding part 12 (Drawing 4).

  In the pressure contact state, the first holding portion 11 and the second holding portion 12 in the holding state are resisted by the urging force of the urging member 15, and are separated from the X direction away from the X direction (FIG. 2A) It moves to the proximity position (FIG. 3 (a)). At this time, the first rectangular conductor C1 protrudes from the first holding portion 11, and the second rectangular conductor C2 protrudes from the second holding portion 12. When the first holding portion 11 and the second holding portion 12 are in the proximity position (FIG. 3A), the protruding amounts A1 and A2 are respectively determined by the lengths of the end faces facing each other in the longitudinal direction of the belt. It is slightly longer. That is, before moving to the proximity position (immediately before), the opposing end faces of the first flat conductor C1 and the second flat conductor C2 first contact (abut). Thereafter, when the first holding portion 11 and the second holding portion 12 move to the close position (FIG. 3A), the abutting end faces of the first rectangular conductor C1 and the second rectangular conductor C2 butt each other. It is put together, pressed and joined. More specifically, by pressing the end faces of the first flat conductor C1 and the second flat conductor C2, stable oxide films formed on the end faces are removed, and these are plastically deformed to be active. Expose the face. By bringing the faces in the active state close to 10 angstroms or less, atomic bonds between metals are caused to perform cold welding. That is, due to cold pressure welding, the lengths of the first rectangular conductor C1 and the second rectangular conductor C2 are compressed (shortened) after pressure welding as compared to before the pressure welding. And the shortening amount is equivalent in the 1st rectangular conductor C1 and the 2nd rectangular conductor C2. That is, when the length of the first flat conductor C1 before pressing is L01, and the length of the second flat conductor C2 before pressing is L02, the length of the first flat conductor C1 is L01 'by the pressing. The rectangular conductor C2 is shortened in length to L02 ', and the shortening amount S is equal (S = L01-L01' = L02-L02 ').

  In addition, since the first holding portion 11 and the second holding portion 12 do not approach any further after moving to the close position, the end faces of the first flat conductor C1 and the second flat conductor C2 are greater than each other. Pressing stops.

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

  In the pressure release state, the first holding portion 11 and the second holding portion 12 in the pressure contact state are respectively moved in the X direction away from each other, and the first holding portion 11 and the second holding portion 12 are released in the X direction. Move to In addition, the first upper holding body 111 and the first lower holding body 112 are moved in the direction to be separated 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. Do. In addition, the second upper holding body 121 and the second lower holding body 122 are moved along the Y direction so as to move away from each other, and the second upper holding body 121 and the second lower holding body 122 are moved to the second Y direction release position. (FIG. 3 (b)).

  In the pressure contact state, the first holding portion 11 and the second holding portion 12 finally reach the proximity position, and further pressing of the first flat conductor C1 and the second flat conductor C2 is stopped, so the pressing is repeated. After the pressure-contacted state, transition to the sandwiching state is made via the pressure-released state, and the first rectangular conductor C1 and the second rectangular conductor C2 are pinched again by the first holding portion 11 and the second holding portion 12.

  Here, when the pressure contact state changes to the pressure contact 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 The same applies to the lower support 122 as it moves away from it. 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 pressing A part (expanded joint surface) of the metal which has flowed by deformation enters a slight clearance (for example, a corner of the groove) of the rectangular conductor holding grooves 111A, 112A, 121A, 122A and the adhesion is enhanced, and the biasing member 15 The first upper holding body 111 and the first lower holding body 112 (as well as the second upper holding body 121 and the second lower holding body 122) may not be able to be separated only by the biasing force of

  Therefore, in the present embodiment, in the pressure-released state (FIG. 3B), in addition to the biasing force of the biasing member 15, the first holding portion (the first upper holding body 111 and the first lower holding body 112) While moving in the direction away from the second holding unit 12 along the X direction and returning it to the first X direction release position, the second holding unit (the second upper holding body 121 and the second lower holding body 122) in the X direction It is made to move to the direction away from the 1st attaching part 11 along, and to return to the 2nd X direction cancellation position.

  In addition, even in the case of forcibly moving the first holding portion 11 and the second holding portion 12 apart from the biasing member 15, the movement control means (not shown) The movement of the second flat conductor C2 in the direction away from each other along the X direction is restricted.

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

  The cold pressure welding apparatus 10 can perform cold pressure welding with one press of rectangular conductors, but in order to stabilize the joint surface, it is desirable to repeat pressing a plurality of times for one joint portion. As an example, the amount of compression (compression amount) of the cold pressure welding apparatus 10 is about 0.5 mm for both the first flat conductor C1 and the second flat conductor C2. Then, when one pressing portion is repeatedly pressed (cold welding) three to four times and compressed by about 1 mm or more (preferably 1.5 mm or more, specifically about 2 mm), stable bonding is obtained. A face is obtained.

  For this reason, the cold pressure welding apparatus 10 of the present embodiment repeats the holding state, the pressure welding state and the pressure welding release state, and cold welds the first flat conductor C1 and the second flat conductor C2.

  As shown in FIG. 3A, when the first holding portion 11 and the second holding portion 12 move to the close position after the holding state and the first holding portion 11 and the second holding portion 12 move to the close position, the end faces of the first flat conductor C1 and the second flat conductor C2 are Through the contact (contact), the end faces are pressed to be cold-welded. Since the first holding unit 11 and the second holding unit 12 in the close position do not approach each other any more, they temporarily shift to the pressure-released state (FIG. 3B), and the first holding unit 11 and the second holding unit 12 The holding portion 12 is moved to the Y direction release position to release the sandwiching of the flat conductor, and the first holding portion 11 and the second holding portion are moved to the X direction release position. Then, the first holding portion 11 holds the first flat rectangular conductor C1 so that the predetermined holding amount A1 is shifted and the second holding portion 12 holds the first holding member so that the protruding amount A2 protrudes. By holding the one rectangular conductor C2 and transitioning to the pressure contact state again, it is possible to repeat a plurality of presses on one joint portion.

  That is, the X direction release position is a position where the first holding portion 11 can hold the first flat conductor C1 with the protrusion amount A1 and hold it, and the second holding portion 12 protrudes the second flat conductor C2. It is a position which can be made to project and hold by quantity A2.

  Note that the X-direction release position may not be a position where each of the flat conductors protrudes by the projection amounts A1 and A2 when the state is shifted to the sandwiching state (as it is) thereafter. In such a case, the first holding portion 11 and the second holding portion 12 may be moved to positions where the flat conductors respectively protrude by the protruding amounts A1 and A2 in the holding state, and then held.

  In the above embodiment, the first holding portion 11 and the second holding portion 12 stop at the X direction releasing position and the Y direction releasing position in the pressure release state, for example. Although the Y direction cancellation position passes, it may not stop at the position. That is, the first upper holding body 111 and the first lower holding body 112 (as well as the second upper holding body 121 and the second lower holding body 122) are not located 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. .

  In the past, cold pressure welding was used when joining round wires, but according to the cold pressure welding apparatus 10 of the present embodiment described above, good and stable cold pressure welding of rectangular conductors is performed. Can.

  Further, by using a coil piece as the rectangular conductor (the first rectangular conductor C1 and the second rectangular conductor C2), the cold pressure welding device 10 can be used as the coil manufacturing device 20. This will be described below.

<Coil manufacturing device>
<Coil manufacturing device / flat conductor (coil piece)>
First, the flat conductor C used in the coil manufacturing apparatus 20 of the present embodiment will be described with reference to FIG. FIG. 5 is a top view of the wide surface WS of the rectangular conductor C. As shown in FIG. The flat conductor C is a plurality of strip-like flat conductors which have a linear shape (the same figure (a)) or at least one bent portion (the same figure (b) to (e)) and can form a spiral shape when they are continued. Hereinafter, these are called coil pieces. The coil pieces having the bent portion are bent in the same direction in the longitudinal direction of the belt so as to form a spiral shape when being continuous. Also, in the case of a coiled piece having a bend, it is preferred that the bend be preferably at least one non-curved (e.g. substantially perpendicular) shape.

  Moreover, in the following description, it is a helical structure in which a plurality of coil pieces (flat conductors) are made continuous (connected), and the helical structure before completion is also included as a coil (helical structure to be completed). Shall be That is, in the following description, the coil piece (flat conductor) includes a plurality of coil pieces of the smallest unit having a linear portion or a bent portion in the same direction in the longitudinal direction of 1 to 4 bands, and a plurality of coil pieces of the smallest unit. It includes a coil piece which is connected and in which a spiral structure of one or more rounds of a coil (to be completed) is formed. Also, for the sake of convenience of explanation, when it is necessary to distinguish between them, the coil piece of the minimum unit is called a unit coil piece, and a plurality of unit coil pieces are connected and completed as a coil (helical structure to be completed) The coil piece before the schedule is called a bonded coil piece, and the helical structure to be completed (finished state) is called a coil. Further, in the plurality of coil pieces, the shape of the cross section perpendicular to the longitudinal direction of the belt and the area thereof are all substantially the same.

  As shown in the figure, the unit coil piece C0 is formed into a shape having a straight or substantially right angled non-curved bent portion (corner portion) by punching a copper plate (for example, 1 mm thick) as an example. Ru. That is, the unit coil piece C0 has a linear shape (I-shaped) without the bent portion (FIG. (A)) or an L-shaped member with one bent portion (FIG. (B)) in top view of the wide surface WS. , U-shaped (C-shaped) having two bent portions (FIG. (C)), substantially C-shaped having three bent portions (FIG. (D)), having four bent portions, the same There is a C-shaped (generally O-shaped (approximately 字 -shaped)) (figure (e) in the figure) that is bent in a direction. It is assumed that the bent portions (corners) have a substantially right-angled shape.

  And a plurality of coil pieces (unit coil pieces and / or joined coil pieces) are completed in the helical longitudinal direction of the helical structure (coil) whose preparation length L0 which becomes the total distance of those strip longitudinal directions is to be completed It is set to be longer by a margin compared to the length. The margin is set to a shortened total distance shortened by pressing when all of the plurality of coil pieces are cold-welded. The preparation length L0, the completed length, the allowance, and the total reduced distance will be described in detail in the description of the method of manufacturing the coil described later.

<Coil manufacturing device / holding part>
The coil manufacturing apparatus 20 according to the present embodiment is an application example of the above-described cold pressure welding apparatus 10, so the same components as those of the cold pressure welding apparatus 10 are denoted by the same reference numerals and redundant description will be omitted. The configuration suitable for use in the coil manufacturing apparatus 20 will be mainly described.

  Referring again to FIG. 1, coil manufacturing apparatus 20 can hold first flat portion 11 and second flat portion 12 opposite to each other while being capable of sandwiching a flat conductor and another flat conductor, respectively. A plurality of strip-like flat rectangular conductors (coil pieces) which can form a helical shape when continuous, are joined to form a helical structure to be a coil, and the total length of the plurality of flat rectangular conductors (coil strips) in the longitudinal direction The preparation length to be the distance is set to be longer by a margin compared to the completion length of the helical structure to be completed, and the end faces of a plurality of flat conductors (coil pieces) are banded. Press along the longitudinal direction to cold weld while shortening the distance in the longitudinal direction of the band, and set a short total distance to shorten all of the flat conductors (coil pieces) by cold welding. To form a helical structure A.

  That is, in the coil manufacturing apparatus according to the present embodiment, the length of the coil piece (joining coil piece) held by the first holding portion 11 or the second holding portion 12 becomes longer as the number of joining (the number of joining) of the coil pieces increases. Therefore, the configuration of the first holding unit 11 and the second holding unit 12 is suitable for use in the manufacture of a coil.

  First, FIG. 6 is a schematic view of a coil piece being manufactured by the coil manufacturing apparatus 20. As shown in FIG. The figure (a) is a schematic view (top view) of the prepared unit coil piece, and the figure (b)-(d) is a developed view of the unit coil piece in process of manufacture, and a joining coil piece, and the same The figure (e) is an arrow view of the V direction of the figure (d).

  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 (consecutively) to form a spiral shape of 2 turns 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 piece in (b) to (d) in the same figure indicate the finished end of the finished coil, and in this example, the finished end does not change (the finish in the left and right direction in the figure) The position of the end does not move.

  First, in the first cold welding, as shown in FIG. 7B, one end face (shown by a circle) of each of the two unit coil pieces C01 and C02 is connected to each other to form a joined coil piece CC1. Then, in the next cold welding, one end face of the joining coil piece CC1 (one of the unjoined end faces of the unit coil pieces C01 and C02) and the unit coil piece C03 are cold-welded, and the joining coil piece CC2 is formed (the same figure (c)), and in the next cold welding, one end face of the joining coil piece CC2 (one of the unjoined end faces of the unit coil pieces C01 and C03) and the unit coil piece Cold welding is performed with C04 to complete the coil 50 (the same figure (d)).

  That is, the first holding portion 11 or the second holding portion 12 holds the bent (here, U-shaped) coil pieces and further increases the length of the joining coil pieces CC1, CC2,. Since there exist in the vicinity of the 1st holding part 11 or the 2nd holding part 12, it is necessary to make the 1st holding part 11 and the 2nd holding part 12 into composition which avoids interference with these coil pieces.

  FIG. 7 is a diagram for explaining the configuration of the first holding unit 11. FIG. 7A is a diagram showing one unit coil piece C0 in the first holding unit 11 (first upper holding body 111 and first lower holding body FIG. 12 is a view showing a state of holding by 112), and is a front view of the facing surface OS2 with the second holding unit 12. FIG. Further, FIG. 7 (b) is a front view of the coil 50 in a completed state as viewed from the axial center direction of the helical structure, and the coil piece of FIG. 7 (a) is a sectional view taken along the line B-B in FIG. It corresponds to the figure. Although the first holding unit 11 will be described here, the same applies to the second holding unit 12. Moreover, the same figure (c) is a front view (the AA line cross section arrow line view of the same figure (a)) of the 1st holding part 11. As shown in FIG.

  As shown to the figure (a) (b), when a coil piece has two or more bending parts (for example, in the case of a U-shaped (U-shaped) coil piece), it joins with the 1st holding part 11 In the area (the same figure (a)) other than the coil piece which is doing, there is a possibility that U-turns from the coil piece C0 held by the 1st holding part 11 and coil piece C0 'extended to the near side interfere. In the present embodiment, in order to avoid this, the dimensions of the first holding portion 11 and the coil piece (the coil 50 to be completed) satisfy the following relationship.

  That is, when connecting a U-shaped (U-shaped) coil piece, one end 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 support 112 and one end surface 112S of the first lower support 112, the end surface orthogonal to the facing surface OS2 is an internal space of the helical structure (a space intended to be an internal space of the helical structure (Hereinafter, this end surface is referred to as a spiral inner end surface IS). The spiral inner end surface IS is, for example, the front of the first holding portion 11 close to the worker.

  Therefore, in order to avoid interference between the first holding portion 11 and the coil piece, the flat conductor holding grooves 111A and 112A of the first holding portion 11 need to be provided at appropriate positions. The distance d1 to the end (upper end in the same figure) of the rectangular conductor holding grooves 111A and 112A is a spiral along the third direction (Z direction in the figure: short side direction of the coil piece for cold welding) It shall be smaller than the distance D1 of the internal space of a structure (coil 50).

  In addition, the length d4 in the X direction (the same figure (c)) of the first holding portion 11 is smaller than the distance D2 (the same figure (b)) in the internal space of the spiral structure (coil 50) along the X direction. It shall be.

  In addition, after cold-welding two coil pieces, the burr | flash 55 by extrusion arises in a connection part. Therefore, after completion of cold pressure welding, coil pieces (joined coil pieces) are taken out from the first holding portion 11 and the second holding portion 12 and deburred, and the coil pieces (joined coil pieces) and others (newly) Cold welding is performed between the coil pieces.

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

  The amount of deformation D3 of the elastic deformation and / or plastic deformation of the coil piece (here, the joined coil piece CC) in the spiral advancing direction 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 where the bonding coil piece of the first holding portion 11 is formed is the coil piece (here, the bonding The amount of deformation D3 allowed for elastic deformation and / or plastic deformation in the direction of spiral movement of the coil piece CC) is smaller than D3.

  As described above, the coil manufacturing apparatus 20 according to the present embodiment forms a spiral structure by joining by cold pressure while elastically deforming and / or plastically deforming coil pieces in the spiral advancing direction (direction along the Y direction). is there. In addition, although coil pieces are connected (added) in a state of being spread in the advancing direction of the helix in the process of manufacturing by this, the helical structure is integrally formed (for example, after the helical structure is in a completed state) , Press, etc.) and perform elastic deformation and / or plastic deformation to be compressed in the advancing direction of the spiral to form a coil 50 in which the respective circumferences of the spiral are in close contact.

  The coil manufacturing apparatus 20 according to the present embodiment uses the coil piece with a longer compression amount (shrinkage amount) than the compression amount (shrinkage amount) due to cold compression based on the completed length of the coil, and performs compression by cold compression ( Coil pieces are added while repeating contraction) to produce a coil of a desired length L.

  Therefore, in the cold pressure welding, the cold pressure welding is performed while measuring the distance in the strip longitudinal direction of the coil pieces. In the measurement of the distance in the longitudinal direction of the belt, for example, by providing a slip detection mechanism (not shown) in the first holding unit 11 and the second holding unit 12 (or in the vicinity thereof), the coil pieces held by the first holding unit 11 By performing slip detection at the time of pressing of the coil piece (second coil piece) held by (the first coil piece) and the second holding unit 12, the distance in the band longitudinal direction can be measured. The measurement of the distance in the longitudinal direction of the belt may be performed simultaneously with cold welding (in real time) or may be measured before or after cold welding (or before or after cold welding). As a result, it is possible to realize high accuracy of the coil dimensions after completion.

  As shown in FIG. 7 (b), the substantially right-angled bent portion of the coil piece is a corner of the coil 50. That is, according to the coil manufacturing apparatus 20 of the present embodiment, by joining together the coil pieces configured to have bent portions substantially orthogonal by punching or the like, the corner portions on the inner peripheral side and the outer peripheral side are substantially perpendicular. Can be manufactured. In the past, a long rectangular conductor was wound to manufacture a coil with a rectangular conductor, but it is inevitable that at least the corner on the inner circumferential side of the coil has a curved shape in winding, and the space factor There is a limit to the improvement of heat and the heat dissipation.

  However, according to the coil manufacturing apparatus of the present embodiment, since the shape formed by punching can be joined as it is, the corner portion of a right angle (approximately right angle) can be realized also on the inner peripheral side of the coil, and the space factor is improved. It is possible to manufacture a coil which can be improved and the heat dissipation can be improved by eliminating the extra space.

  In particular, the joint portion CP is provided on 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 which is formed at right angle (approximately right angle) in punching.

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

  That is, in the coil manufacturing method of the present embodiment, a plurality of strip-shaped flat rectangular conductors (coil pieces) which can form a helical structure when being continuous are prepared, and a preparation is made to be the total distance of the plurality of rectangular conductors (coil strips) in the strip longitudinal direction. The length L0 is set to be longer by a margin M as compared with the completed length L of the helical structure (coil) to be completed, and the end faces of a plurality of flat conductors (coil pieces) Press along the longitudinal direction of the strip to cold press while shortening the distance in the longitudinal direction of the strip, and reduce the total distance S by which all of the flat conductors (coil pieces) are shortened by cold welding By setting, a plurality of flat conductors (coil pieces) are joined to form a spiral 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 (consecutively) The case of manufacturing a coil (helical structure) 50 having a spiral shape of two turns will be described as an example. Similar to FIG. 6, FIG. 6A is a top view of the coil pieces C01 to C04, and FIGS. 6B to 6D are developments of the connecting coil pieces, and the broken line in the drawing is the completion plan. The axial center of the helical structure of the coil 50 (the center of the joint CP) is shown. In addition, the alternate long and two short dashes lines at both ends of the coil piece in (b) to (d) in the same figure show the finished end of the finished coil, and in this example, the finished end does not change ( The position of the finished end 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, which is the total distance in the longitudinal direction of the belt, is L01 + L02 + L03 + L04. The preparation length L0 is set to be longer than the completed length L of the coil 50 in the longitudinal direction of the coil 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 strip and cold-welded, the length L01 of the unit longitudinal direction C01 is compressed to L01 ′ (shortened The amount of compression is the distance S1 from the center of the joint CP), and the length L02 of the unit coil segment C02 is compressed to L02 'in the longitudinal direction of the band ((the shortening (compression) amount is the distance S2 from the center of the joint CP) Length is carried out to form a joined coil piece CC1 (length LC1) (FIG. 7 (b)), and an end face of the joined coil piece CC1 (end face of the unit coil piece C01 or C02 not joined) When the unit coil piece C03 is cold-welded, the unit coil piece C03 is compressed to L03 ′ by these pressure (the amount of shortening (compression) is the distance S3 from the center of the bonding portion CP), and the bonding coil piece CC1 is , It is compressed to C1 '((the amount of shortening (compression) is the distance S4 from the center of the bonding portion CP) to form the bonding coil piece CC2 (FIG. 6C). When the unit coil pieces C04 are cold-welded to the end surfaces of the unit coil pieces C01 and C03 which are not joined, the unit coil pieces C04 are compressed to L04 ′ by these presses (the shortening (compression) amount is the joint portion Bonded coil piece CC2 is compressed to LC2 ′ ((the shortening (compression) amount is the length of distance S6 from the center of the joint CP)), and the completed length in the helical longitudinal direction (start point) The coil 50 (helical structure) of length L from ST to end point SE is completed (the same figure (d)) Coil pieces (unit coil pieces and / or joined coil pieces) are joined to complete the coil 50 Of the coil pieces until 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 the present embodiment will be described again in chronological order. 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 reduction distance S = the allowance M, and the compression amounts S1 to S1 by cold pressure welding are set. S6 is set.

  Then, using the coil pieces set in this manner, the end faces of the unit coil piece C01 and the unit coil piece C02 are pressed by the set compression amount S1 and S2 and added by cold pressure welding to form a joined coil piece CC1 Do. The amounts of compression S1 and S2 at this time are grasped by measuring the distance in the longitudinal direction of the strip of the two coil pieces by performing slip detection 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 as in the following cold welding.

  After cold welding of one joint region (for example, near the end face where the unit coil piece C01 and the unit coil piece C02 are to be joined), burrs are generated by pressing in the joint portion. I do.

  Next, the spiral advancing direction of the helical structure to be completed leaving the vicinity of the end face (end face of unit coil piece C01 or unit coil piece C02 not joined) in which the coil piece (joining coil piece CC1) is cold-welded Cold-welding with another coil piece (unit coil piece C03) while being elastically deformed and / or plastically deformed. At this time, the amount of deformation of elastic deformation and / or plastic deformation in the spiral advancing direction of the joined coil piece CC1 is determined by the first holding portion 11 and the second holding portion 12 in which the coil piece is held during cold pressure welding, and the joined coil piece It is set to an amount to avoid interference with CC1. Further, the amount of deformation is the same in the following cold welding.

  Thereafter, the coil pieces are added similarly. That is, the end face of the joining coil piece CC1 (the end face of the unit coil piece C01 or C02 not joined) and the unit coil piece C03 are pressed by the set compression amount S3, S4 and joined by cold pressure welding The coil piece CC2 is formed. Thereafter, deburring of the bonding region is performed, and the bonding coil piece CC2 is elastically and / or plastically deformed in the spiral advancing direction of the helical structure to be completed leaving the vicinity of the end face to be cold welded. The end face of the CC2 and the unit coil piece C04 are pressed by the set compression amount S5, S6 for joining by cold pressure welding to obtain a completed helical structure.

  FIG. 10 is a view showing an example of the completed helical structure 50 ′ (the number of turns of the coil is different from that of the above embodiment). FIG. 10 (a) is a front view as viewed from the helical axis direction, FIG. 10 (b) is an arrow view (side view) in the V direction before forming, and FIG. 10 (c) (d) is after forming Side view of FIG.

  The completed helical structure 50 'is formed by pressing or the like. That is, in order to avoid buffer with the first holding portion 11 and the second holding portion 12 during cold pressure welding, elastic deformation and / or plastic deformation in the spiral traveling direction of the spiral structure allows each space between the spirals to be deformed. Since unnecessary and nonuniform spreads (spaces) are formed, the elastic deformation and / or plastic deformation of the helical structure in the helical direction of the helical structure so as to compress it, each circumference of the helical as much as possible Close (close) (Figure (c)).

  Furthermore, according to the shape of the stator core, it may be concave or convex in the axial center direction of the helical structure (radial direction of the stator core) according to the shape 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 formed helical structure is dipped in a liquid insulating resin and integrally covered with the insulating resin. In addition, you may coat | cover integrally with insulation resin by spraying a liquid insulation resin to the helical structure after shaping | molding. Conventionally, after covering a long wire for the completed length of a coil with an insulating resin, this is wound to form a spiral structure. However, in this case, in the vicinity of the outer periphery of the curved portion of the winding, the insulating resin is stretched and the coating thickness becomes thin, which causes the deterioration of the pressure resistance. Also, for example, in the case of coating with the insulating resin before the above molding, the same problem occurs because the coating thickness of the insulating resin varies due to the press. In this embodiment, since the helical structure molded into the shape attached to the stator core is integrally covered with the insulating resin after molding, the uniformity of the film thickness of the insulating resin can be enhanced. Moreover, since it coat | covers integrally with insulation resin after shaping | molding, helical structures can be adhere | attached by insulation resin, and it can coat | cover with uniform film thickness.

<Modification of coil piece>
FIG. 11 is a view showing an example of connection in the case where the shapes of the coil pieces are different.

  The same figure (a) is a top view which shows the example of a connection by a L-shaped coil piece, and, here, the case where the connection coil piece for 1 round is comprised, using four L-shaped coil pieces C0. It shows. Although illustration is omitted for convenience of explanation, also in this case, the preparation length L0 which becomes the total distance in the longitudinal direction of the strip in each coil piece is the completion length in the helical longitudinal direction of the helical structure (coil) to be completed The margin M is set to be longer than the margin L by a margin M. The margin M is set to a shortened total distance S which is shortened by pressing when all of the plurality of coil pieces are cold-welded.

  In addition, the connection coil pieces for one turn may not be configured in the same shape (L-shape). That is, L-shaped I-shaped (linear) and U-shaped (U-shaped) coil pieces may be combined to form a connecting coil piece for one turn.

  The figure (b) is a top view which shows the example of a connection which combined the C-shaped coil piece C0 and the I-shaped coil piece C1. Although illustration is omitted for convenience of explanation, also in this case, the preparation length L0 which becomes the total distance in the longitudinal direction of the strip in each coil piece is the completion length in the helical longitudinal direction of the helical structure (coil) to be completed The margin M is set to be longer than the margin L by a margin M. The margin M is set to a shortened total distance S which is shortened by pressing when all of the plurality of coil pieces are cold-welded.

  In addition, a coil piece with three substantially C-shaped corners and an L-shaped coil piece may be combined to form a connecting coil piece for one turn. Furthermore, the coil pieces constituting the first and second turns of the helical structure may be different combinations.

  In the same figure (c), there are two U-shaped (U-shaped) coil pieces C0 at one corner and a coil piece (O-shaped (R-shaped) coil for one turn of the spiral structure to be completed It is an expanded view in the case of forming a joining coil piece in combination with piece) C1. The two-dot chain lines at both ends of the coil piece in the figure indicate the finished end of the finished coil, and 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) It explains as a thing.

  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 is compressed by S0 and the O-shaped coil piece C1 is compressed by S1. This can be compressed and repeated to form a helical structure. In FIG. 9 (when the U-shaped coil piece C0 having the same length is used), as shown in the figure, the joint portion CP has substantially the same position along the axial center of the helical structure at each circumference of the helical structure. In the case of FIG. 11 (c), the junction CP is formed at a position deviated by a predetermined amount along the axial center (broken line) of the helical structure at each circumference of the helical structure. Ru.

<Modification of coil>
FIG. 12 is a view showing a modified example of the coil manufacturing apparatus and the coil manufacturing method. FIG. 10A is a schematic view of a coil manufacturing apparatus 20 ′, and FIG. 10B is a side view corresponding to FIG. 10C of a coil 50 manufactured thereby. c) is a perspective view of the coil 50. FIG.

  As shown to the figure (a), coil manufacturing apparatus 20 'is provided with two or more holding | maintenance units 22 which consist of the above-mentioned 1st holding | maintenance part 11 and 2nd holding | maintenance part 12, and several holding | maintenance units 22 (22A-22E) are. The width W (width along the Z direction, width of the flat conductor in the width direction BS of the flat conductor) of the flat conductor holding grooves 111A, 112A, 121A, 122A of the first holding portion 11 and the second holding portion 12 are different (sequentially It may be large (or small).

  As described above, by using a plurality of holding units 22 having different widths W of the rectangular conductor holding grooves 111A, 112A, 121A, 122A, flat conductors with different widths (widths WA to WE in the drawing) can be joined. That is, while sequentially moving between the plurality of holding units 22, cold welding is performed by different holding units 22 for each circumference of the spiral structure, thereby forming a spiral structure having different lengths for each circumference of the coil. it can. That is, by using U-shaped (U-shaped) unit coil pieces of the same length in the longitudinal direction of the strip, the coil pieces are joined together by cold welding while sequentially moving between the plurality of holding units 22. Then, the coil 50 (the figure (b) (c)) which has the outline of a quadrangular frustum can be formed.

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

<Coil>
Next, the coil of the present embodiment will be described with reference to FIG. FIG. 13 (a) is a front view seen from the axial center direction of the helical structure, and FIG. 13 (b) is a cross-sectional view taken along the line AA of FIG. Further, FIG. 7 (c) is a side view of FIG. 7 (a) viewed from the V direction.

  The coil 50 according to the present embodiment is formed of a spiral structure in which strip-shaped flat rectangular conductors (coil pieces) are continued in a spiral shape, and as shown in FIG. It has a non-curved corner (a substantially right-angled corner) 50C. Here, as an example, the coil is manufactured using the above-described coil manufacturing apparatus and coil manufacturing method.

  In the case of a coil formed by winding a long flat conductor longer than one turn of the helical structure of the conventional complete coil, it is inevitable that the bent portion becomes a curved structure, and when attached to the stator core It creates a large space. Since the heat retention effect is enhanced in the blank portion, there is a limit to the improvement of the heat dissipation of the coil. In addition, when a long flat rectangular conductor is covered with an insulating resin and then wound, there is a problem that the thickness of the covering of the insulating resin becomes thin 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 1 round of the helical structure of a coil by stamping, it can form the coil of a desired shape in a plain view. That is, along the shape of the stator core, a coil 50 (with at least the inner circumferential corner 50C being at right angles or near right angles) having an infinitely close shape is obtained. This makes it possible to minimize the space between the stator core 60 (shown by a broken line in FIG. 6A), unlike the coil of the winding method. For example, the length of the space (the distance from the inner peripheral side of the coil 50 to the stator core 60) can be reduced to 0.5 mm to 1.0 mm per side of the coil 50, whereby the heat dissipation can be improved. Further, since the insulating resin can be coated with enhanced uniformity over the entire coil 50, it is possible to suppress the deterioration of the withstand voltage due to the variation of the film thickness of the insulating resin.

  Further, in the coil 50 of the present embodiment, the width orthogonal to the spiral traveling direction of the helical structure (width W1 in the band width direction of the coil piece) becomes the widening width W2 at the corner, thereby also reducing coil resistance. can do.

  Furthermore, since cold welding is an atomic bond of metal, the connection is surely joined to such an extent that it is not visible. Thereby, the stability of the connection portion can be overwhelmingly enhanced as compared with a configuration in which a coil for one rotation (or less) is planarly connected with an adhesive (fixing material, brazing or the like).

  Further, as shown in (b) of the figure, the first circumference of the spiral of the helical structure (for example, the first circumference due to the joined coil piece CC1) is a part of the flat conductor (coil piece) of the other part. A first thin portion T1 having a thickness D8 thinner than the thickness D7 is provided. Also, the second circumference (for example, the second circumference by the joining coil piece CC2) continuous to the first circumference has a plate thickness D8 in part compared to the plate thickness D7 of the flat conductor (coil piece) in the other part. A thin second thin portion T2 is provided.

  As described above, at the time of cold welding, the coil pieces are held by the first holding portion 11 and the second holding portion 12 of the coil manufacturing apparatus 20. At that time, the total depth of the rectangular conductor holding grooves 111A and 112A ( The same applies to the total depth of the flat conductor holding grooves 121A and 122A) is smaller than the thickness D7 of the coil piece. Then, the coil pieces are held between the first holding portion 11 and the second holding portion 12 by being pressed by the pressing portion 18, and the holding portions are the rectangular conductor holding grooves 121A and 122A and the rectangular conductor holding grooves 111A and 112A. It is compressed in the thickness direction to a thickness (D8) substantially equal to the total depth. The portion held by the first holding portion 11 and the second holding portion 12 is a first thin portion T1 and a second thin portion T2. That is, the first thin-walled portion T1 and the second thin-walled portion T2 are formed corresponding to the bonding portion CP of cold pressure welding, and for example, U-shaped (U-shaped) coil pieces are connected In the case of the coil, the first thin portions T1 are provided at two places in the first circumference, and the second thin portions T2 are also provided at two places in the second circumference. When all U-shaped unit coil pieces have the same length, the first thin portion T1 and the second thin portion T2 overlap with each other in the axial center direction of the helical structure, as indicated by the dashed square. Provided in

  In addition, as shown in FIG. 11, the first thin portion T1 and the second thin portion T2 formed corresponding to the joint portion CP of cold pressure welding have U-shaped (U-shaped) and O-shaped coil pieces. In the case of a combination of (shape of L), it is formed at a position shifted alternately on the first circumference and the second circumference corresponding to the joint portion CP (in the case of the O-shaped coil piece And a thin portion is formed at only one place in one cycle).

  And as for the coil 50, all the circumference | surroundings which comprise a helical structure are coat | covered integrally with the insulation resin. Thereby, the adhesiveness of each circumference of a spiral structure can be improved. Further, the gap SP of the coil piece is formed between the first thin portion T1 and the second thin portion T2, but a part of the insulating resin is also embedded in the gap SP. That is, as described in the above-described manufacturing method, since the helical structure is immersed in the liquid insulating resin after completion of the helical structure (which is molded as necessary), the insulating resin intrudes into the gap portion SP. Thereby, the adhesion of each circumference of the spiral structure can be further enhanced.

  Further, the coil 50 is formed so as to be concave or convex in the axial center direction of the helical structure (radial direction of the stator core) in accordance with 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 the figure which measured and compared the emitted-heat amount of the coil 50 of this embodiment, and the coil (round wire coil) comprised by winding round wire. The calorific value (temperature) with the passage of time was measured at 5 V and 20 A for the round wire coil and the coil 50 of the present embodiment.

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

  As is clear from this result, the coil (a coil having a substantially perpendicular inner circumference (inner circumference right-angled coil)) 50 of this embodiment has a temperature close to normal temperature (for example, 40 ° C. to 50 ° C.) It can be said that the heat dissipation is very high, though there is almost no temperature rise. And by such high heat dissipation, coil resistance can be greatly reduced compared with the past.

  In addition, the width W3 of the start and end portions of the spiral structure of the coil 50 may be wider than the width W1 in the band width direction. This can reduce the coil resistance at the start and end portions as well as at the corners.

  In the present embodiment, the coil 50 which is perpendicular to the inner periphery and in which the end faces of the coil pieces are repeatedly joined by cold pressure welding has been described. However, the present invention is not limited to this, and the end faces of the coil pieces may be joined by another joining method. Specifically, various connection methods such as ultrasonic welding (high frequency welding), electric welding, and brazing can be adopted.

<How to attach to stator core>
The example of attachment to the stator core of the coil 50 of this embodiment is demonstrated with reference to FIG. FIG. 15 (a) is a side view of the coil 50 and the cassettes 51A, 51B. FIG. 15 (b) is a cross-sectional view taken along the line c-c of FIG. 15 (a). FIG. 15C is a cross-sectional view corresponding to a cross section along line c-c in FIG. 15A showing an example of attachment to the stator core 60.

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

  Therefore, for example, as shown in FIG. 6A, two cassettes 51A and 51B having flanges 52A and 52B on one surface side in the axial center direction of the helical structure of the coil 50 are prepared. The coil 50 is inserted from the side where the collar portion 52A is not formed, and the other cassette 51B is overlapped and engaged with each other. Then, the cassette coil 50 is inserted into the stator core 60. The cassettes 51A and 51B are provided with a notch or an engaging portion 53 so as to fit in a top view of the cross section shown in FIG.

As shown in FIG. 6C, the coil 50 may be attached to one cassette 51C having the flange 52B only on one side in the axial center direction of the helical structure and attached to the stator core 60. In that case, in order to prevent the coil 50 from coming off (or causing unnecessary movement (vibration)) from the stator core 60 due to the centrifugal force at the time of operation, the stator core 60 is provided with the notch 61 and the cassette coil 50 is After mounting to 60, it is good to fit with the retaining ring 62 which covers the upper direction of the coil 50 with a cassette, and the notch 61 of the stator core 60. As shown in FIG.
<Helical structure of coil>
The helical 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, and FIG. 16 (a) is a side view seen from the short side of the embodiment, and FIG. 16 (b) is seen from the long side It is a side view, and the figure (c) is a side view seen from the short side of another example, and the figure (d) is a side view seen from the long side, and the figure (e) Is a side view seen from the short side of still another embodiment. FIG. 17 is a modification of FIGS. 16 (c) and 16 (e), and FIGS. 17 (a) and 17 (c) are external perspective views, and FIGS. 17 (b) and 17 (d) are respectively the same. 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. 16 (a) and 16 (b), a first spiral is formed. Between the circumference TC1 and the second circumference TC2, it is gradually deformed along the spiral advancing direction to absorb the thickness of the unit coil piece, and this is repeated for each circumference.

  That is, in the coil 50 according to an example of the present embodiment, strictly, as shown in FIGS. 6A and 6B, each coil piece is connected to the next coil piece while being slightly inclined, A helical structure is formed. Here, although 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, all four side surfaces of the coil 50 are the same. Incline.

  Moreover, the coil 50 of the present embodiment is not limited to the above-described structure, and may have a helical structure as shown in FIGS. (C) to (e).

  That is, as shown in FIG. 6C, in a part of the first circumference TC1 of the spiral of the spiral structure, deformation is performed so that the step B corresponding to the thickness of the coil piece is made along the spiral traveling direction. In a part of the second circumference TC2 of the spiral, deformation is performed so that a step B corresponding to the thickness of the coil piece can be made along the spiral traveling direction, and this is repeated to form a spiral structure. The step B is formed only on one side surface (for example, one side surface on the short side) of the coil 50 and is formed on the same portion, that is, on the step B on the first periphery. Step B is formed.

  As described above, since the thickness of the coil piece is absorbed by the step B formed on only one side surface, the other three side surfaces have the respective coil pieces as shown in the side view on the long side of FIG. It will not be inclined but will be stacked approximately horizontally.

  According to such a configuration, the surface of the outermost coil can be flattened without the start end SE and the end end EE of the coil 50 protruding. That is, in the spiral structure of FIGS. 6A and 6B, as shown in FIG. 5A, the surface (lower end surface in the figure) of the coil 50 including the start end SE is the coil surface SF12 of the start end SE. A level difference is generated between the coil surface SF11 'and the facing coil surface SF11', which is not the same surface. Similarly, the surface (upper end surface in the drawing) of the coil 50 including the end end EE is not flush with the coil surface SF21 ′ of the end end EE and the coil surface SF22 ′ on the side opposite to the coil surface SF21 ′. In the case where the thickness of the coil piece is relatively thin, the occurrence of such a step is less of a problem. However, in the case where the coil pieces are thick, it is necessary to secure a space corresponding to this step when setting in the cassettes 51A and 51B as shown in FIG. In addition, a gap may occur, which may cause a problem such as rattling of the coil 50.

  On the other hand, in the helical structure of (c) and (d) in the same figure, the surface (lower end surface in the figure) of the coil 50 including the start end SE is a coil on the opposite side that wound around the coil surface SF12 of the start end SE. The surface (upper end surface in the figure) of the coil 50 including the end end EE (the upper end surface in the figure) provided on the same surface as the surface SF11 (approximately) is also the same (approximately) the coil surface SF22 on the side facing the coil surface SF21 of the end end EE. It is provided on the surface. As a result, the size reduction of the outer shape of the coil 50 can be realized, and the adhesion to the cassettes 51A and 51B can be enhanced.

  The figure (e) is the same helical structure as the figure (c) and (d), but is another example from which the shape of a coil piece differs. The coil pieces may have a square shape in cross section (approximately) as shown in FIG. 6E, in which the width W and the thickness d2 of the widthwise direction BS are substantially equal. When the thickness d2 is larger than the width W as described above, it is more preferable to adopt a helical structure in which the step B is provided on one side surface of the coil 50 as shown in FIG.

  FIG. 17 is a diagram showing another example of this embodiment. As shown in the figure, all of the coil pieces constituting the coil 50 (all coil pieces connected along the spiral traveling direction) have different widths W and thicknesses d2 of the band width direction BS. It is also good. For example, in the coil 50 shown in the figure, the coil pieces whose thickness d2 gradually becomes thinner as the width W of each coil piece gradually expands from the start end SE to the end end EE (WA, WB...) Connected

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

  By doing this, the desired square frustum coil 50 can be manufactured. Further, as in this example, when a plurality of coil pieces having different thicknesses d2 are used, if a spiral structure as shown in FIG. 16A is employed, the thickness d2 of the coil pieces at the start end SE and the end end EE. This causes a difference in the value of the step on the coil surface of the outermost circumference (uppermost and lowermost circumferences in the figure). As a result, the outer size of the coil 50 increases and the shape becomes uneven (asymmetric), so it is necessary to secure an extra space in the cassettes 51A and 51B. In addition, the possibility that the steady attachment to the cassettes 51A and 51B becomes difficult also increases. In such a case, by forming a step B on one side surface of the coil 50, even if the thicknesses d2 of the coil pieces are different, the coil surface of the outermost periphery is (substantially) flat. Since the coil surfaces SF11 and SF12 can be the same surface, and the coil surfaces SF21 and SF22 can be the same surface, significant reduction in size of the coil outer shape 50 can be realized, and the cassettes 51A and 51B can be The trouble at the time of attachment can be avoided.

  In the above example, the step B is provided on one side which is the short side of the coil 50. However, the step B may be provided on one side which is the long side of the coil 50. The position to be provided can be appropriately selected 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 have a curved shape.

  Further, one coil piece is not limited to one formed by punching a single copper plate, and a plurality of narrow rectangular conductors (for example, flat rectangular conductors having a square cross-sectional shape in the longitudinal direction of the band as shown in FIG. 16 (e) ) May be arranged in parallel in the short side direction of the coil. In addition, the coil may be partially formed by a coil piece formed by punching a single copper plate, and a portion may be formed by a coil piece formed by parallel arrangement of narrow rectangular conductors.

  The present invention can be used, for example, when manufacturing a coil device using a flat coil.

10 cold pressure welding apparatus 20 coil manufacturing apparatus 11 first holding unit 12 second holding unit 50 coil

Claims (4)

A method of manufacturing a coil, comprising preparing a plurality of strip-like flat conductors which can form a helical structure when being continuous, and joining the end faces of the plurality of flat conductors to form the helical structure.
A pressure welding step of butting and pressing one end face of the first flat conductor in the longitudinal direction of the strip and one end face of the second flat conductor in the longitudinal direction of the strip;
Removing the burrs generated by the pressing;
Method of manufacturing a coil characterized in that. After the removal step,
The other end face of the second flat conductor in the longitudinal direction of the band and the other end face of the third flat conductor in the longitudinal direction of the band are pressed against each other.
The method of manufacturing a coil according to claim 1, Alternately repeating the removing step and the other pressing step;
The method of manufacturing a coil according to claim 2, characterized in that: Integrally covering the finished helical structure with a coating,
A method of manufacturing a coil according to any one of claims 1 to 3, characterized in that.

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