JP2021086953A - Coil assembly and transformer with the same - Google Patents

Abstract

To provide a coil assembly capable of easily securing insulation quality between conductor wires positioned on both sides while nipping a flange part and miniaturizing a mounting space, and to provide a transformer with them.SOLUTION: A coil assembly 1 includes: a bobbin 2; and a winding 31. The bobbin 2 includes: a cylindrical part 22; and a flange part 21. In the flange part 21, a penetration hole 211 is formed. The winding 31 is formed by wounding the conductive wire 3 so as to be laminated to a coil radial direction to the bobbin 2. The conductive wire 3 is inserted into the penetration hole 211. The conductive wire 3 is arranged along both side surfaces 24 of the flange part 21, and forms the winding 31 so as to be wound along at least one side surface 24. The penetration hole 211 is formed so that both the conductor wires 3 arranged along the side surface 24 are housed in an inner side from an outer peripheral opposite part 32 facing at an outermost peripheral side from a position facing to a coil axial direction while nipping the flange part 21.SELECTED DRAWING: Figure 1

Description

The present invention relates to a coil assembly and a transformer including the coil assembly.

For example, as a component constituting a magnetic component such as a transformer, there is a coil assembly in which a conductor wire is wound around an insulating bobbin. The transformer described in Patent Document 1 has a coil assembly in which a flange is interposed and a conductor wire is wound around a bobbin having a flange and a tubular portion into which a core is inserted. Then, by forming a notch-shaped passage that reaches the outer circumference of the tubular portion from the outer circumference of the flange, the conductor wire is wound between the flanges without being routed to the outer circumference of the flange.

Japanese Unexamined Patent Publication No. 2006-128735

However, the coil assembly described in Patent Document 1 has the following problems.
In the coil assembly, there are portions of conductor wires located on both sides of the flange where the potential difference between them is large. Further, since the passage of the flange is formed between the portions having a large potential difference in the conductor wire, it becomes difficult to secure the insulating property between the portions by the flange. Further, in order to secure the insulating property by the space distance, it is necessary to increase the thickness of the flange, and the mounting space of the coil assembly tends to be large.

The present invention has been made in view of the above problems, and is a coil assembly and a coil assembly capable of easily ensuring insulation between conductor wires located on both sides of a flange portion and reducing the mounting space. It is intended to provide a transformer equipped with this.

One aspect of the present invention has a tubular portion (22) and a flange portion (21) provided around the tubular portion so as to project outward from the outer peripheral surface (221) of the tubular portion. The bobbin (2) is formed with a through hole (211) penetrating in the coil axial direction (Z).
A coil assembly (1) having a winding (31) formed by winding a conductor wire (3) around the bobbin so as to be laminated in the coil radial direction.
The conductor wire is inserted through the through hole, arranged along both side surfaces (24) of the flange portion in the coil axial direction, and wound along at least one of the side surfaces to form the winding. And
The through hole is located inside the outer peripheral facing portion (32), which is the most outer peripheral side of the positions where the conductor wires arranged along the side surface face each other in the coil axial direction with the flange portion sandwiched between them. It is in a coil assembly that is formed to fit.

Another aspect of the present invention is in a transformer (10) provided with the coil assembly.

In the coil assembly, the through hole formed in the flange portion is formed so as to fit inside the outer peripheral facing portion. Then, the conductor wires arranged along both side surfaces of the flange portion are continuous through the portion inserted through the through hole. Therefore, the potential difference between the conductor wires facing each other across the through hole can be reduced. Therefore, the insulating property can be ensured without increasing the distance between the conductor wires facing each other across the through hole. As a result, the insulation between the conductor wires can be easily secured, and the mounting space can be reduced.

Further, the transformer includes a coil assembly that can be miniaturized as described above. Therefore, the transformer can be easily miniaturized.

As described above, according to the above aspect, the coil assembly and the transformer provided with the coil assembly can easily secure the insulation between the conductor wires located on both sides of the flange portion and can reduce the mounting space. Can be provided.
The reference numerals in parentheses described in the scope of claims and the means for solving the problem indicate the correspondence with the specific means described in the embodiments described later, and limit the technical scope of the present invention. It's not a thing.

The plan view of the coil assembly seen from the Z direction in Embodiment 1. FIG. The plan view of the coil assembly in the state which the tape was removed in Embodiment 1. FIG. The perspective view of the bobbin in Embodiment 1. The plan view of the bobbin seen from the Z direction in Embodiment 1. The plan view of the bobbin seen from the X direction in Embodiment 1. FIG. 4 is a cross-sectional view of a bobbin corresponding to a cross section taken along the line VI-VI in FIG. The plan view of the coil assembly seen from the X direction in Embodiment 1. FIG. FIG. 2 is a cross-sectional view of a coil assembly corresponding to a cross section taken along the line VIII-VIII in FIG. FIG. 5 is a cross-sectional view of a coil assembly in a state in which a conductor wire is wound around a bobbin using a winding jig according to the first embodiment. The plan view of the transformer seen from the Z direction in Embodiment 1. An exploded perspective view of a transformer according to the first embodiment. FIG. 10 is a cross-sectional view of a transformer corresponding to the cross section taken along the line XII-XII in FIG. The plan view of one of the secondary coils seen from the Z direction in Embodiment 1. The plan view of the bobbin seen from the Z direction in Embodiment 2. The plan view of the bobbin in which the position of the through hole is changed in the second embodiment.

(Embodiment 1)
An embodiment relating to a coil assembly and a transformer including the coil assembly will be described with reference to FIGS. 1 to 13.
As shown in FIG. 1, the coil assembly 1 of the present embodiment has a bobbin 2 and a winding 31. As shown in FIGS. 3 and 4, the bobbin 2 has a tubular portion 22 and a flange portion 21 provided so as to project outward from the outer peripheral surface 221 of the tubular portion 22. The flange portion 21 is formed with a through hole 211 penetrating in the coil axial direction Z.

As shown in FIG. 8, the winding 31 is wound around the bobbin 2 so that the conductor wire 3 is laminated in the coil radial direction. The conductor wire 3 is inserted through the through hole 211. The conductor wire 3 is arranged along both side surfaces 24 of the flange portion 21 in the coil axial direction Z. The conductor wire 3 is wound along at least one side surface 24 to form a winding 31. In this embodiment, the conductor wire 3 forms a winding 31 along both side surfaces 24 of the flange portion 21.

As shown in FIGS. 1 and 2, the through hole 211 is formed so as to fit inside the outer peripheral facing portion 32. As shown in FIG. 7, the outer peripheral facing portion 32 is a portion where the conductor wires 3 arranged along the side surface 24 face each other on the outermost outer side of the positions facing the coil axial direction Z with the flange portion 21 interposed therebetween. ..

The coil radial direction is the radial direction of the winding 31. Further, in the coil radial direction, the alignment direction of the tubular portion 22 and the through hole 211 is referred to as the Y direction. Further, among the coil radial directions, the direction orthogonal to the Y direction is referred to as the X direction. The coil axial direction Z is also appropriately referred to simply as the Z direction.

As shown in FIGS. 1, 2, and 4, the bobbin 2 has a tubular portion 22 substantially at the center thereof when viewed from the Z direction. As shown in FIGS. 3 and 4, the tubular portion 22 is open in both the Z directions. As shown in FIG. 5, the tubular portion 22 is formed so as to project outward from each side surface 24 of the flange portion 21 in the Z direction. The flange portion 21 is provided around the tubular portion 22 in the coil radial direction from substantially the center in the Z direction. As shown in FIGS. 3 and 4, a through hole 211 is formed in a part of the flange portion 21.

From the viewpoint of ensuring the insulating property of the flange portion 21, the through hole 211 is preferably arranged at a more inner position in the radial direction. From this point of view, as shown in FIGS. 1 and 2, the through hole 211 is formed so as to be accommodated inside the intermediate position M between the outer peripheral facing portion 32 and the outer peripheral surface 221 of the tubular portion 22 in the coil radial direction. It is preferable that it is. Further, as shown in FIGS. 3 and 4, the through hole 211 is preferably formed so as to be in contact with the tubular portion 22. In this embodiment, a part of the contour of the through hole 211 is formed by a part of the outer peripheral surface 221 of the tubular portion 22. The portion of the contour of the through hole 211 that is farthest from the tubular portion 22 is located inside the intermediate position M as shown in FIGS. 1 and 2. Further, the width of the through hole 211 in the coil radial direction is larger than the width of the conductor wire 3. Further, the width of the through hole 211 in the coil radial direction can be twice or less the width of the conductor wire 3.

Further, as shown in FIG. 4, the through hole 211 is longer in the coil circumferential direction than in the coil radial direction. The length of the through hole 211 in the coil circumferential direction can be, for example, about 5 to 10 times the width of the conductor wire 3.

As shown in FIGS. 3 and 4, the through hole 211 is formed in a substantially arc shape along the outer circumference of the tubular portion 22 when viewed from the Z direction. The formation range of the through hole 211 in the coil circumferential direction is a range of less than 180 ° with respect to the center of the tubular portion 22. Further, the formation range of the through hole 211 in the coil circumferential direction is a range of 90 ° or less with respect to the central angle of the tubular portion 22 as a reference.

As shown in FIG. 6, the end portion of the flange portion 21 facing the through hole 211 exhibits a convex curved surface shape protruding inward of the through hole 211.

Further, as shown in FIGS. 1 to 4, the flange portion 21 has a protruding portion 23 projecting to the outer peripheral side at a position in the coil circumferential direction in which the through hole 211 is formed. That is, a protruding portion 23 is formed on the side opposite to the tubular portion 22 with the through hole 211 in the Y direction interposed therebetween.

The protruding portion 23 projects toward the outer peripheral side of the outer peripheral contours of the two windings 31. The outer peripheral contours of the two windings 31 are contained inside the outer peripheral contours of the flange portion 21.

The bobbin 2 is made of, for example, a resin molded product. When molding the bobbin 2, a pair of molds that move relative to each other in the Z direction can be used. That is, the bobbin 2 has a shape that allows die cutting in the Z direction, including the through hole 211.

Further, as shown in FIG. 8, a conductor wire 3 is inserted through the through hole 211. The conductor wire 3 forms a winding 31 by two portions on both sides of the portion inserted through the through hole 211. Further, as shown in FIG. 1, the winding 31 is fixed to the bobbin 2 by the tape 4. In this embodiment, tapes 4 are attached to the coil assembly 1 at four locations. The winding 31 arranged along one side surface 24 of the flange portion 21 is fixed to the bobbin 2 by two tapes 4. The winding 31 arranged along the other side surface 24 is also fixed to the bobbin 2 by two tapes 4 in the same manner.

The width of the conductor wire 3 in the coil radial direction is larger than the thickness in the coil axial direction Z. The conductor wire 3 is made of, for example, copper or an alloy of copper, and its surface is covered with an insulating coating (not shown). The conductor wire 3 is a flat wire having a substantially rectangular cross-sectional shape due to a plane orthogonal to the longitudinal direction. Then, the conductor wire 3 having such a shape is wound around the bobbin 2 as follows to form the winding 31.

First, the conductor wire 3 is inserted into the through hole 211 of the bobbin 2. The portion of the conductor wire 3 inserted through the through hole 211 is in an inclined state with respect to the flange portion 21. Further, at this stage, the portions on both sides of the portion are also arranged on both sides of the flange portion 21 in a state of being inclined with respect to the flange portion 21.

Next, as shown in FIG. 9, the bobbin 2 in which the conductor wire 3 is inserted through the through hole 211 is sandwiched by a pair of winding jigs 5 from both sides in the Z direction. The winding jig 5 has a central contact surface 51 that contacts the tubular portion 22 from the Z direction, and a flange facing surface 52 that is arranged to face the flange portion 21 from the Z direction.

When the above-mentioned bobbin 2 is sandwiched between a pair of winding jigs 5, the flange facing surface 52 is in a state where a gap 53 for forming a winding 31 is formed between the flange facing surface 52 and the flange portion 21. It is arranged to face the flange portion 21. At this time, a part of the conductor wires 3 arranged on both side surfaces 24 of the flange portion 21 is pressed toward the flange portion 21 by the flange facing surface 52. As a result, the portions on both sides of the portion of the conductor wire 3 inserted through the through hole 211 are formed along the flange portion 21. The conductor wire 3 is arranged so that the thickness direction faces the Z direction.

After that, the two portions on both sides of the portion of the conductor wire 3 inserted through the through hole 211 are wound around the gap 53, respectively. At this time, the conductor wire 3 is spirally wound from the position facing the outer peripheral surface 221 of the tubular portion 22 toward the outer peripheral side. Further, the two windings 31 arranged on both side surfaces 24 of the flange portion 21 are set so that the winding directions are opposite to each other. That is, the conductor wire 3 is wound by so-called "α winding" to form two windings 31.

After forming the winding 31 on the bobbin 2, the winding jig 5 is removed from the bobbin 2. Next, as shown in FIG. 1, the tape 4 is attached over the winding 31 and the flange portion 21 of the bobbin 2.

As shown in FIGS. 2 and 4, the flange portion 21 has a straight portion 212 in which a part of the outer contour thereof is formed in a straight line by a length equal to or longer than the width of the tape 4 when viewed from the Z direction. Then, as shown in FIG. 1, the tape 4 is attached to the flange portion 21 and the winding 31 so as to pass through the straight portion 212. That is, in the straight portion 212, the tape 4 is folded back from one side surface 24 of the flange portion 21 to the other side surface 24. As a result, the winding 31 is fixed to the bobbin 2.

Further, in the present embodiment, the coil assembly 1 is assembled as a component of the transformer 10 as shown in FIG. That is, the transformer 10 includes the coil assembly 1.

The transformer 10 is formed by laminating a coil assembly 1, a secondary coil 101, and a core portion 105 in the coil axial direction Z. In the transformer 10 of this embodiment, the coil assembly 1 is the primary coil of the transformer 10.

More specifically, the coil assembly 1 is assembled so as to be sandwiched from both sides in the Z direction by two secondary coils 101. Then, the two core portions 105 are assembled so as to sandwich the coil assembly 1 and the two secondary coils 101 from both sides in the Z direction. As a result, the transformer 10 is assembled as shown in FIG. The two core portions 105 are temporarily fixed by the core tape 41.

As shown in FIGS. 11 to 13, the secondary coil 101 has a conductor plate 102 and a resin portion 103 formed so as to cover the conductor plate 102. The resin portion 103 is formed of an insulating resin. The secondary coil 101 is insert-molded.

Further, as shown in FIGS. 11 and 12, the outer peripheral wall portion 104 extends from the outer peripheral end of one of the secondary coils 101 toward the side where the coil assembly 1 is arranged in the Z direction with respect to the secondary coil 101. It is installed. As shown in FIG. 13, the outer peripheral wall portion 104 extends from the outer peripheral ends on both sides in the X direction with the insertion hole 107 of the secondary coil 101 interposed therebetween. The outer peripheral wall portion 104 is integrally formed with the resin portion 103.

As shown in FIG. 12, the outer peripheral wall portion 104 is arranged between the coil assembly 1 and the core portion 105 in the coil radial direction.

Further, as shown in FIG. 11, in the transformer 10, an elastic member 106 is interposed between the coil assembly 1 and the secondary coil 101, and between the secondary coil 101 and the core portion 105. As shown in FIG. 12, the elastic member 106 is elastically compressed in the coil axial direction Z between the elastic members 106. The elastic member 106 is made of, for example, an insulating silicone resin.

Next, the action and effect of this embodiment will be described.
In the coil assembly 1 of the present embodiment, the through hole 211 formed in the flange portion 21 is formed so as to be accommodated inside the outer peripheral facing portion 32. The conductor wires 3 arranged along the side surfaces 24 of the flange portion 21 are continuous through the portions inserted into the through holes 211. Therefore, the potential difference between the conductor wires 3 facing each other across the through hole 211 can be reduced. Therefore, the insulating property can be ensured without increasing the distance between the conductor wires 3 facing each other across the through hole 211. As a result, the insulation between the conductor wires 3 can be easily ensured, and the mounting space can be reduced.

Further, the through hole 211 is formed so as to fit inside the intermediate position M. Therefore, the potential difference between the conductor wires 3 facing each other across the through hole 211 can be further reduced.

Further, the through hole 211 is formed so as to be in contact with the tubular portion 22. Therefore, the potential difference between the conductor wires 3 facing each other across the through hole 211 can be further reduced.

Further, the end portion of the flange portion 21 facing the through hole 211 exhibits a convex curved surface shape protruding inward of the through hole 211. Therefore, when the conductor wire 3 is wound, the insulating coating formed on the surface of the conductor wire 3 is not easily damaged. As a result, it is easy to secure the insulating property between the conductor wires 3.

Further, as shown in FIG. 2, the outer periphery of the winding 31 tends to partially protrude toward the outer periphery at the position in the coil circumferential direction in which the through hole 211 at the start of winding of the winding 31 is formed. In the present embodiment, the flange portion 21 has a protruding portion 23 at a position in the coil circumferential direction in which the through hole 211 is formed. Therefore, the width of the flange portion 21 in the coil radial direction can be increased at the coil circumferential position where the protruding portion 23 is formed. As a result, it is easy to secure the insulating property between the conductor wires 3 arranged along both side surfaces 24 of the flange portion 21.

Further, the through hole 211 is longer in the coil circumferential direction than in the coil radial direction. Therefore, even when the winding 31 is formed along both side surfaces 24 of the flange portion 21, the potential difference between the conductor wires 3 facing each other across the through hole 211 can be reduced, and the winding 31 is wound. When turning, it becomes easy to wind without projecting a part of the winding 31 in the Z direction. As a result, it is easy to achieve both improvement of the insulating property between the conductor wires 3 and miniaturization of the coil assembly 1.

Further, the conductor wire 3 has a wider width in the coil radial direction than a thickness in the Z direction. Therefore, it is easy to reduce the size of the coil assembly 1 in the Z direction.

Further, the winding 31 is fixed to the bobbin 2 by the tape 4. Therefore, the assembling workability of the coil assembly 1 can be improved. Further, it is possible to fix the winding by using the conductor wire 3 as a self-bonding electric wire, but the self-bonding electric wire itself is expensive, and a heater for curing and a curing time are required. The cost tends to be high. On the other hand, in this embodiment, since it is fixed by the tape 4, it is easy to reduce the cost as compared with the case where the self-bonding electric wire is adopted.

Further, the flange portion 21 has a straight portion 212. Therefore, when the winding 31 is fixed to the bobbin 2 by the tape 4, the tape 4 can be easily attached by folding back from one side surface 24 to the other side surface 24 at the straight portion 212. As a result, the winding 31 can be securely fixed to the bobbin 2, wrinkles are less likely to occur on the tape 4, and workability can be improved.

In this embodiment, the bobbin 2 has only one flange portion 21. Therefore, when molding the bobbin 2, a pair of molds that move relative to each other in the Z direction can be used. That is, the bobbin 2 can be die-cut in the Z direction including the through hole 211. As a result, when manufacturing the bobbin 2, the structure of the mold can be simplified and the productivity can be improved.

Further, the transformer 10 of this embodiment includes a coil assembly 1 that can be miniaturized as described above. Therefore, the transformer 10 can be easily miniaturized.

Further, in the transformer 10 of the present embodiment, the outer peripheral wall portion 104 extends from the outer peripheral end of one of the secondary coils 101. Therefore, it is easy to secure the insulating property between the conductor wire 3 of the coil assembly 1 and the core portion 105.

As described above, according to the present embodiment, the coil assembly 1 and the coil assembly 1 which can easily secure the insulation between the conductor wires 3 located on both sides of the flange portion 21 and can reduce the mounting space. The transformer 10 provided can be provided.

(Embodiment 2)
As shown in FIGS. 14 and 15, this embodiment is a form in which the position of the through hole 211 in the bobbin 2 in the coil circumferential direction is changed.
Others are the same as in the first embodiment. In addition, among the codes used in the second and subsequent embodiments, the same codes as those used in the above-described embodiments represent the same components and the like as those in the above-mentioned embodiments, unless otherwise specified.

As described in the first embodiment, the through hole 211 penetrates in the Z direction. Therefore, when the bobbin 2 is molded, the penetrating direction of the through hole 211 is likely to match the die cutting direction. From this point of view, the forming position of the through hole 211 in the coil circumferential direction is not particularly limited, and can be appropriately changed as in the present embodiment.

For example, it is conceivable to adjust the number of turns of the winding 31 by changing the positional relationship between the terminal 33 and the through hole 211. In such a case, the desired coil assembly 1 can be obtained by appropriately changing the coil circumferential position of the through hole 211. In addition, in FIGS. 14 and 15, the shape of the bobbin 2 is the same as that of the first embodiment (see FIG. 4), but it can be changed as appropriate. That is, it is conceivable to change the forming position of the protruding portion 23 in accordance with the change in the coil circumferential position of the through hole 211.
In addition to the positions shown in FIGS. 14 and 15, various positions of the through hole 211 in the coil circumferential direction can be considered.

Further, in the coil assembly 1 of the first embodiment, two windings 31 are formed along both side surfaces 24 of the flange portion 21. However, for example, one winding 31 may be formed along one side surface 24 of the flange portion 21, and the winding 31 may not be formed on the other side surface 24.

The present invention is not limited to each of the above embodiments, and can be applied to various embodiments without departing from the gist thereof.

1 Coil assembly 2 Bobbin 21 Flange part 211 Through hole 22 Cylindrical part 221 Outer peripheral surface 24 Side surface 3 Conductor wire 31 Winding 32 Outer peripheral facing part Z Coil axial direction

Claims (8)

It has a tubular portion (22) and a flange portion (21) provided around the outer peripheral surface (221) of the tubular portion so as to project outward, and the flange portion has a coil axial direction (Z). ) Is formed with a through hole (211), and the bobbin (2)
A coil assembly (1) having a winding (31) formed by winding a conductor wire (3) around the bobbin so as to be laminated in the coil radial direction.
The conductor wire is inserted through the through hole, arranged along both side surfaces (24) of the flange portion in the coil axial direction, and wound along at least one of the side surfaces to form the winding. And
The through hole is located inside the outer peripheral facing portion (32), which is the most outer peripheral side of the positions where the conductor wires arranged along the side surface face each other in the coil axial direction with the flange portion sandwiched between them. A coil assembly that is formed to fit. The through hole according to claim 1, wherein the through hole is formed so as to be accommodated inside the intermediate position (M) between the outer peripheral facing portion and the outer peripheral surface of the tubular portion in the coil radial direction. Coil assembly. The coil assembly according to claim 2, wherein the through hole is formed so as to be in contact with the tubular portion. The coil assembly according to any one of claims 1 to 3, wherein the flange portion has a protruding portion (23) projecting to the outer peripheral side at a position in the coil circumferential direction in which the through hole is formed. The coil assembly according to any one of claims 1 to 4, wherein the through hole is longer in the coil circumferential direction than in the coil radial direction. The coil assembly according to any one of claims 1 to 5, wherein the conductor wire has a width in the coil radial direction larger than a thickness in the coil axial direction. The coil assembly according to any one of claims 1 to 6, wherein the winding is fixed to the bobbin by a tape (4). A transformer (10) comprising the coil assembly according to any one of claims 1 to 7.

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