JP4808191B2 - Molded coil - Google Patents

Description

  The present invention relates to a molded coil mainly used as an outer coil of a resin molded transformer.

  Conventionally, a unit coil group is configured by arranging a plurality of unit coils side by side in the winding axis direction, and a mold in which a series of unit coils constituting the unit coil group are sequentially connected in series to form one coil. In the transformer coil, each unit coil has a structure in which a strip-shaped thin plate conductor is continuously wound for a predetermined number of turns with insulation between layers, and a series of unit coils constituting the unit coil group are adjacent to each other. The unit coil is arranged in a state where the winding directions of the matching unit coils are alternately changed, and the series of unit coils are connected to the end of winding and the start of winding of adjacent unit coils on the inner peripheral side of the coil. Are connected in series with a crossover connection structure in which winding ends and winding ends of adjacent unit coils adjacent to each other on the outer peripheral side are alternately arranged in the winding axis direction, and are integrally formed into a cylindrical shape by a resin. mold There are those (e.g., see Patent Document 1).

  In addition, each unit coil is individually molded in an annular shape with resin, and a plurality of molded coils each provided with a unit coil lead terminal on each surface are stacked in the axial direction so that the lead terminals of each mold coil are electrically connected to each other. (For example, refer to Patent Document 2).

JP 2004-119682 A Japanese Utility Model Publication No. 05-018015

  However, according to the technique described in Patent Document 1, since the molding is performed after adjusting the arrangement of the unit coils with a spacer or the like and combining the entire unit coils, the mold workability is poor, and voids are easily generated. There was a problem of poor heat dissipation. Furthermore, there is a problem that workability is poor when performing a cross connection for connecting the winding end and winding start of adjacent unit coils on the inner peripheral side of the coil.

  Further, according to the technique described in Patent Document 2, since the lead terminal extending from the inner periphery side of the unit coil to the outer periphery side is molded together with the unit coil, it is necessary to secure an insulation distance between the lead terminal and the unit coil. There is a problem that the space factor in the axial direction of the unit coil is deteriorated and the axial length of the molded coil is increased. Further, since the mold including the lead terminal is molded at the time of molding, there is a problem that workability is poor and each mold coil is easily displaced in the direction perpendicular to the axis.

  The present invention has been made in view of the above, and an object of the present invention is to obtain a molded coil that facilitates molding work, reduces the size of the mold part, reduces the amount of mold resin used, and improves heat dissipation. .

In order to solve the above-described problems and achieve the object, the present invention includes a unit coil in which a coil conductor is wound to form a short cylindrical shape, a coil is molded with a mold resin, and the outer shape is formed into a short cylindrical shape. Connected to the winding start end of the coil conductor on the inner peripheral side of the coil, a lead part drawn to the outside of the mold resin in the coil axial direction, and the mold resin extending from the lead part in the coil radial direction A winding start terminal having a connecting portion extending to the outside of the coil, and a winding end terminal connected to the winding end of the coil conductor on the outer peripheral side of the coil and extending radially outward of the mold resin. molded coil in which a plurality of mold units coil, stacked in the coil axis direction via the spacers upside down alternately, connecting the terminals to each other start the winding adjacent and winding end terminals are made Te The leading portion of the winding start terminal is disposed at a position shifted in the circumferential direction from the position of the spacer, and the leading end portion of the transition portion is disposed at the same circumferential position as the outer spacer of the spacer. It is characterized by.

  According to the present invention, it is possible to obtain a molded coil that facilitates a molding operation, reduces the size of the mold part, reduces the amount of mold resin used, and improves heat dissipation.

  Embodiments of a molded coil according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment FIG. 1 is a longitudinal sectional view showing a coil axis Z-direction laminated structure of a mold unit coil in a molded coil according to an embodiment of the present invention, and FIG. 2 shows a combined structure of three mold unit coils. FIG. 3A is a cross-sectional view taken along line AA in FIG. 1, and FIG. 3B is a cross-sectional view taken along line CC in FIG. 3 is a partial cross-sectional view showing another example of the winding start terminal, FIG. 4-1 is a partial longitudinal sectional view of the mold unit coil showing the winding start terminal lead-out structure, and FIG. FIG. 5A is a partial longitudinal sectional view of a mold unit coil showing another example of a winding start terminal lead-out structure, FIG. 5A is a partial longitudinal sectional view showing a terminal lead-out structure of the mold unit coil, and FIG. FIG. 5D is an enlarged view of part D of FIG. 5-1, and FIG. 5-3 is a terminal drawing of the mold unit coil. FIG. 6A is a longitudinal sectional view of a mold coil showing a laminated structure of mold unit coils by spacers, and FIG. 6B is a side view of the spacer 6. FIG. 6-3 is a side view of the spacer 7, and FIG. 6-4 is a partial longitudinal sectional view of the mold coil showing the laminated structure of the mold unit coil by another spacer. 1 is a longitudinal sectional view of a molded coil showing a structure for attaching a terminal cover to a winding end terminal, and FIG. 7-2 is an enlarged view of a portion B in FIG. 7-1.

  As shown in FIGS. 1 to 6-3, the mold unit coil 10 is formed into a rectangular short cylindrical shape by winding a coil conductor 1 (see FIGS. 4A to 5C) coated with an insulating material a predetermined number of times. The formed coil 2 is molded with a mold resin 3, and the outer shape is formed into a square short tube shape (see FIGS. 3-1 and 3-2).

  The L-shaped winding start terminal 4 connected to the winding start end 1a (see FIGS. 4-1 and 4-2) of the coil conductor 1 on the inner peripheral side of the coil 2 is connected to the coil axis Z from the inner peripheral portion of the coil 2. It is drawn out to the outside of the mold resin 3 in the direction, bent at a right angle, and extended in the coil radial direction so as to extend to the outside of the mold resin 3 of the mold unit coil 10.

  The winding start terminal 4 is connected to the winding start end 1a (see FIGS. 4-1 and 4-2) of the coil conductor 1 on the inner peripheral side of the coil 2, and is drawn out to the outside of the mold resin 3 in the coil axis Z direction. Since the lead portion 4c and the transition portion 4b extending from the lead portion 4c in the radial direction of the coil 2 and extending to the outside of the mold resin 3 of the mold unit coil 10 are formed, the transition portion 4b is not molded. The mold work is easy.

  As shown in FIG. 4A, the lead portion 4c extends over the entire inner length of the coil 2, and the lead portion 4c and the winding start end 1a of the coil conductor 1 are electrically connected to each other, and the winding start end 1a. The other coil conductor 1 and the lead portion 4c are insulated by an insulator 3a. Further, as shown in FIG. 4B, the lead portion 4c extends to the winding start end 1a inside the coil 2 and is electrically connected, and the inner portion of the coil conductor 1 other than the winding start end 1a is You may make it fill with the insulator 3a.

  As shown in FIG. 3A, the lead-out portion 4c of the winding start terminal 4 is disposed at a position Y shifted from the center line O of the short side of the square of the mold unit coil 10, and the crossover portion 4b is bent at a right angle to form a coil. Extending in the radial direction, the front end portion 4 a of the crossover portion 4 b is disposed on the center line O outside the mold unit coil 10. In FIG. 3A, the winding end terminal 5 is not shown.

  As shown in FIGS. 3-2, 4-1, and 4-2, the winding end terminal 5 connected to the winding end 1b of the coil conductor 1 on the outer peripheral side of the coil 2 is a square of the molded unit coil 10. On the short side center line O, it extends to the outside of the mold resin 3 in the radial direction. In FIG. 3-2, the winding start terminal 4 is not shown.

  As shown in FIGS. 1, 2, 3-1 and 3-2, the winding start terminal 4 is placed on the upper side of the uppermost mold unit coil 10 of the molded coil 20 with the top and bottom reversed. The molded unit coils 10 having the same shape are stacked via four spacers 7 that are spaced apart by 90 ° in the circumferential direction.

  On the lower side, similar to the uppermost mold unit coil 10, the mold unit coil 10 with the top and bottom facing up and the winding end terminal 5 on the upper side is laminated via four spacers 6. The The spacers 6 are arranged radially on the center line of each square side of the molded unit coil 10.

  Hereinafter, similarly, the mold unit coils 10 having the same shape with the top and bottom reversed are stacked in the coil axis Z direction via the spacer 6 or the spacer 7, and the mold coil 20 of the embodiment has six pieces of the same shape. The mold unit coil 10 is laminated.

  As shown in FIGS. 2, 3-1, 6-1 and 6-3, the spacers 7 disposed on the lower side of the uppermost mold unit coil 10 and the upper side of the lowermost mold unit coil 10 are The flanges 7a and 7a are provided at both ends, and are formed in a prismatic shape having a length corresponding to the thickness of the mold unit coil 10 in the radial direction. The inner and outer peripheral portions of the upper and lower mold unit coils 10 and 10 are sandwiched between the flanges 7a and 7a at both ends, thereby preventing the upper and lower mold unit coils 10 and 10 from being displaced in the radial direction.

  The inner flange 7 a is provided with an inner spacer 7 b that fixes the molded coil 20 to the inner molded coil 30. As illustrated in FIG. 6B, the spacer 6 disposed in the middle portion of the molded coil 20 has a structure that does not include the inner spacer 7 b of the spacer 7. As shown in FIG. 6A, an iron core 50 is inserted into the inner mold coil 30.

  As shown in FIGS. 2 and 3-1, tip portions 4a and 4a of adjacent upper and lower winding start terminals 4 and 4 are overlapped with each other and fastened and connected by bolts and nuts 8 (see FIG. 1). Further, as shown in FIGS. 2 and 3-2, the adjacent upper and lower winding end terminals 5, 5 are fastened and connected by a U-shaped conductor 9 (see FIG. 1) and a bolt / nut 8.

  When a current flows in from the winding end terminal 5 of the uppermost mold unit coil 10 in FIG. 1 (which becomes the winding start terminal of the mold coil 20), the mold unit coil 10 whose top and bottom are reversed is wound. Since current flows from the beginning terminal 4, the direction of the magnetic flux generated by the upper and lower mold unit coils 10 and 10 is the same, and the mold coil 20 has a single number of turns that is six times the number of turns of the mold unit coil 10. Acts as a coil.

  As described above, in the mold coil 20 according to the embodiment, the transition part 4b of the winding start terminal 4 is disposed outside the mold resin 3, and the mold unit coil 10 having the same shape is laminated via the spacers 6 and 7. Therefore, heat dissipation is good due to the spacer. Further, the mold unit coil 10 is downsized (thinned), and the amount of the mold resin 3 used is reduced.

  As shown in FIGS. 3-3, 4-1, and 4-2, the winding start terminal 24 as another example of the winding start terminal 4 is a center line of the short side of the square of the molded unit coil 10. It is drawn from the position Y shifted from O to the outside of the mold resin 3 in the coil axis Z direction (drawer portion 24c), bent at a right angle and extended in the coil radial direction parallel to the center line O, and outside the mold unit coil 10. It bends at right angles toward the center line O (crossover portion 24b), and the tip end portion 24a is arranged so as to be positioned on the center line O outside the mold unit coil 10. Instead of the winding start terminal 4, a winding start terminal 24 may be used.

  Further, as shown in FIGS. 5A, 5B, and 5C, the winding start terminal 34 as still another example of the winding start terminal is connected to the winding start end 1a of the coil conductor 1. An L-shaped lead portion 34c is embedded in the mold resin 3, and a separate connecting portion 34b fastened to the lead portion 34c with a bolt 34d extends in the coil radial direction to the outside of the mold unit coil 10. It extends. Since the connecting portion 34b of the winding start terminal 34 is a separate body, the mold unit coil can be easily stored.

  As shown in FIG. 3A, the lead-out portion 34c of the winding start terminal 34 is disposed at a position Y that is shifted from the center line O of the short side of the square of the mold unit coil 10, and the separate connecting portion 34b has a coil diameter. Extending in the direction, the leading end 34 a of the crossover 34 b is disposed on the center line O on the outer side of the mold unit coil 10. Instead of the winding start terminal 4, a winding start terminal 34 may be used.

  As shown in FIG. 6-4, the spacer 36 as another example of the spacer 6 has flanges 36a and 36a at both ends, and the total length including the thickness of the flanges 36a and 36a It is formed in a prismatic shape having a length corresponding to the thickness in the radial direction.

  The flanges 36a and 36a at both ends are fitted into recesses formed in the outer and inner peripheral portions of the upper and lower mold unit coils 10 and 10, respectively. The upper and lower mold unit coils 10 and 10 are prevented from shifting in the radial direction and the circumferential direction by fitting the flanges 36a and 36a at both ends into the recesses.

  Although not illustrated, the mold coil 20 can be fixed to the inner mold coil 30 by providing an inner spacer similar to the inner spacer 7b on the inner flange 36a. Instead of the spacers 6 and 7, a spacer 36 may be used.

  As shown in FIGS. 7A and 7B, on the side where the winding start terminal 4 and the winding end terminal 5 of the molded coil 20 are drawn, a band-shaped terminal cover 40 is attached so as to cover the terminals. . One piece of the L-shaped terminal 41 is fastened to the winding end terminal 5 of the uppermost mold unit coil 10 by a bolt / nut 43 (see FIG. 7-1, not shown in FIG. 7-2).

  Another terminal 42 is fastened to the other piece of the L-shaped terminal 41 by a bolt / nut 44, an insulating nut 45 is fastened to the tip of the bolt / nut 44, and the upper end of the terminal cover 40 is fastened to the other end of the insulating nut 45 by an insulating bolt 46. Is installed. Although not shown, similarly, the lower portion of the terminal cover 40 is fastened to the winding end terminal 5 of the lowermost mold unit coil 10.

  In FIG. 7A, an example in which the winding end terminal 5 of the mold unit coil 10 is used as the winding start terminal of the mold coil 20 is shown, but when the winding start terminal 4 is used as the winding start terminal of the mold coil 20, Then, the terminal cover 40 is attached using the connection terminal with the upper mold unit coil 10.

  Although the mold unit coil 10 of the embodiment is formed in a square short cylindrical shape, it may be formed in a circular short cylindrical shape. Although the mold coil 20 has shown an example in which six (six steps) mold unit coils 10 are connected, the number of the mold unit coils 10 to be connected varies depending on the capacity and winding of the mold coil 20, and is limited to six. Not.

  As shown in FIG. 3A, an example in which four spacers 6 and 7 are arranged in one stage has been shown. However, the number of spacers 6 and 7 is selected according to the shape of the mold unit coil 10 and the coil mass. . As shown in FIG. 6A, the inner spacer 7b is installed on the lower side of the uppermost mold unit coil 10 and the upper side of the lowermost mold unit coil 10, but it may be installed at other positions. . Further, the thickness (height) of the spacer arranged between the mold unit coils 10 and 10 in which the winding end terminals 5 and 5 are connected by the U-shaped conductor 9 may be reduced.

  As described above, the molded coil according to the present invention is suitable for the outer coil of the resin mold transformer.

It is a longitudinal cross-sectional view which shows the coil-axis Z direction laminated structure of the mold unit coil in the mold coil concerning embodiment of this invention. It is a front view which shows the combination structure of three mold unit coils. It is a cross-sectional view which follows the AA line of FIG. It is a cross-sectional view which follows the CC line of FIG. It is a partial cross section figure which shows the other example of a winding start terminal. It is a fragmentary longitudinal cross-sectional view of the mold unit coil which shows a winding start terminal extraction structure. It is a fragmentary longitudinal cross-sectional view of the mold unit coil which shows the other example of a winding start terminal lead-out structure. It is a fragmentary longitudinal cross-section which shows the terminal extraction structure of a mold unit coil. It is the D section enlarged view of FIGS. It is a fragmentary longitudinal cross-section which shows the other example of the terminal extraction structure of a mold unit coil. It is a longitudinal cross-sectional view of the mold coil which shows the laminated structure of the unit coil by a spacer. It is a side view of a spacer. It is a side view of a spacer. It is a partial longitudinal cross-sectional view of the mold coil which shows the laminated structure of the unit coil by another spacer. It is a longitudinal cross-sectional view of the mold coil which shows the attachment structure of the terminal cover to a winding end terminal. It is the B section enlarged view of FIGS.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Coil conductor 1a Winding start end 2 Coil 3 Mold resin 4, 24, 34 Winding start terminal 4a, 24a, 34a End part of a transition part 5 Winding end terminal 6, 7, 36 Spacer 6a, 7a, 36a Flange 7b Inner spacer 8 Bolt / Nut 9 Co-shaped conductor 10 Mold unit coil (unit coil)
20 Mold coil 30 Inner mold coil 40 Terminal cover

Claims (6)

A unit coil formed by winding a coil conductor to form a short cylinder and molding the resin with a mold resin to form the outer shape into a short cylinder;
Connected to the winding start end of the coil conductor on the inner peripheral side of the coil, a lead part drawn to the outside of the mold resin in the coil axial direction, and the mold resin extending from the lead part in the coil radial direction A winding start terminal having a transition portion extending to the outside of the
The winding end terminal connected to the winding end of the coil conductor on the outer peripheral side of the coil and extending to the outside of the mold resin in the radial direction;
A plurality of mold units coil consisting comprise, stacked in the coil axis direction via a spacer to the upside down alternately, a mode Rudokoiru of connecting the terminals to each other start the winding adjacent and winding end terminals are ,
The lead-out portion of the winding start terminal is disposed at a position shifted in the circumferential direction from the position of the spacer, and the leading end portion of the crossover portion is disposed at the same circumferential position as the outer spacer of the spacer. Mold coil characterized by.   2. The mold coil according to claim 1, wherein the spacer is formed in a columnar shape having flanges at both ends, and sandwiches an inner peripheral portion and an outer peripheral portion of two mold unit coils laminated by the flanges at both ends.   The molded coil according to claim 2, wherein an inner spacer for fixing the molded coil to an inner molded coil is provided on an inner flange of the spacer.   The molded coil according to claim 2 or 3, wherein concave portions are formed in an inner peripheral portion and an outer peripheral portion of the mold unit coil, and a flange of the spacer is fitted into the concave portion.   The mold unit coil is formed in a square short cylinder shape, and the spacers are arranged radially on the center line of each side of the square of the mold unit coil. The molded coil according to 1. The winding and the start lead-out portion and the connecting portions of the terminals, molded coil according to any one of claims 1-5, characterized in that the separate bodies.

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