JP6400335B2 - Coil parts and electronic equipment - Google Patents

Description

  The present invention relates to a coil component and an electronic device, and more specifically to an extraction structure of an air-core coil formed by a flat wire.

  As the performance of electronic devices such as portable devices increases, parts used in the electronic devices are also required to have high performance. However, as the performance of electronic devices increases, the number of components also increases, and the movement of miniaturization of components is increasing. The same applies to coil parts with high current characteristics using windings, and measures to further reduce the size are being studied.

  In order to obtain high current characteristics, there have been many coil parts that use a rectangular conductive wire called a flat wire. However, although it is relatively easy to form the loop portion, the lead wire from the lead portion to the connection to the terminal electrode is difficult to bend due to the direction of the lead wire, and requires a large space. Alternatively, as shown in Patent Document 1 below, a coil formed by winding a conducting wire having a flat cross section is placed on a tablet formed in a shape having a columnar convex portion on a flat peripheral edge, and both ends of the coil are placed. There is also a structure in which the portion is along the outer side surface of the columnar convex portion of the tablet and a part thereof is exposed from the sealing material and connected to the external electrode.

JP 2010-245473 A

  In the technique described in Patent Document 1 described above, the drawer position can be stabilized by fixing the drawer portion to a block (columnar convex portion) as shown in FIG. However, a large space for providing the block is required, which is a limitation in promoting downsizing. For this reason, in order to advance downsizing with a coil component of the type embedded in the magnetic body, it is a problem to form the extraction portion with high accuracy in a small space.

  The present invention focuses on the above points, and an object of the present invention is to provide a coil component that can reduce the space of the lead-out portion and can be miniaturized in an air-core coil using a flat wire. And Another object is to provide an electronic device using the coil component.

  The coil component of the present invention is a coil component in which an air-core coil is embedded in a magnetic material, and the air-core coil uses a rectangular wire having a cross section of a conducting wire having a long side and a short side, and the length of the rectangular wire is long. Each of the intermediate portions from the intermediate portion to the opposite ends, respectively, and a drawing portion for drawing out to the terminal electrode on the surface of the magnetic body, and the winding portion of the rectangular wire The surface on one long side of the cross section is wound so as to be parallel to the winding axis, and the lead-out portion is bent toward one short side of the cross section of the rectangular wire at the end of the winding portion. It is characterized by being. One of the main forms is characterized in that the lead portion is bent at an angle of 90 ° or less with respect to a rectangular wire at the end of the circulating portion.

In another embodiment, the coil axis is formed by a circular portion of the air-core coil, and a cross section perpendicular to the axial direction of the coil axis has a shape having a major axis and a minor axis. . Yet another embodiment, in a cross section perpendicular to the axial direction of the coil axis, wherein the lead portion is directed Cow direction to an end portion of the lead portion terminating as a starting point of the circulation portion, away from the coil axis It is a direction. In another embodiment, in the cross section perpendicular to the axial direction of the coil axis, the direction of the lead-out portion starting from the end of the turn portion toward the end of the lead-out portion is the outer peripheral surface of the turn portion. In contrast , it has an angle of 0 to 45 °.

Still another embodiment is characterized in that, in a cross section perpendicular to the axial direction of the coil shaft, the terminal end of each of the lead portions is arranged on one side in the short axis direction. Still another embodiment is characterized in that, in a cross section perpendicular to the axial direction of the coil axis, the terminal end of each of the lead portions is arranged across the coil axis in the major axis direction. To do. Yet another embodiment is characterized in that the coil shaft is formed by a circular portion of the air-core coil, and a cross section perpendicular to the axial direction of the coil shaft is an oval type.

  An electronic apparatus according to the present invention includes any one of the coil components described above. The above and other objects, features and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings.

  According to the present invention, the air-core coil embedded in the magnetic body is formed by a flat wire, and the circumferential portion of the air-core coil has a surface on one long side of the cross-section of the flat wire as a winding axis. The lead portion of the air-core coil is bent toward one short side of the cross section of the rectangular wire at the end of the loop portion and connected to the terminal electrode on the surface of the magnetic body. For this reason, the space | interval of a drawer part can be reduced and the small coil components without a useless space can be obtained. In particular, by bending the drawing portion toward one short side of the cross section of the rectangular wire, the strength of the drawing portion can be obtained, and the winding portion can be prevented from loosening by stabilizing the position of the drawing portion. The variation in characteristics (inductance) can be reduced, and the connection stability with the terminal electrode can be obtained. Thereby, even a small component such as a chip component can stably produce a high-performance component.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the coil components of Example 1 of this invention, (A) is a top view, (B) is the elements on larger scale of said (A), (C) looks at said (A) from arrow F1 direction. (D) is a diagram showing a cross-sectional shape of a rectangular wire forming a coil. It is a figure which shows the circulation procedure of the coil of the said Example 1. FIG. It is a figure which shows the specific example of the air-core coil of the said Example 1, (A) is a top view, (B) is the side view which looked at the said (A) from the arrow F3a direction, (C) is said (A) It is the side view which looked at from arrow F3b direction. It is a figure which shows the other specific example of the air-core coil of the said Example 1, (A) is a top view, (B) is the side view which looked at the said (A) from the arrow F4a direction, (C) is the said ( It is the side view which looked at A) from arrow F4b direction.

  Hereinafter, the best mode for carrying out the present invention will be described in detail based on examples.

  First, the basic structure of Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing a coil component of the present embodiment, where (A) is a plan view, (B) is a partially enlarged view of (A), and (C) is the above (A) from the direction of arrow F1. A side view, (D) is a diagram showing a cross-sectional shape of a rectangular wire forming a coil. FIG. 2 is a diagram showing a coil winding procedure of the present embodiment. As shown in FIG. 1A, the coil component 10 of the present embodiment has a configuration in which an air-core coil 20 is embedded in a substantially rectangular parallelepiped magnetic body 12. The magnetic body 12 is made of a resin and a metal magnetic material. Terminal electrodes 14 and 16 are provided on both sides of the bottom surface of the magnetic body 12, and lead portions 24 A and 24 B on both ends of the air-core coil 20 are connected to the terminal electrodes 14 and 16.

  In the present embodiment, as the conducting wire for winding the air-core coil 20, as shown in FIG. 1 (D), the cross section of the conducting wire called a rectangular wire has long sides 30C, 30D and short sides 30A, 30B. A rectangular shape with a coating for insulation on the surface of the conductive wire was used. The air-core coil 20 is formed by a winding portion 22 wound with a flat wire 30 and lead-out portions 24A and 24B connecting the winding portion 22 and the terminal electrodes 14 and 16. The circumference portion 22 was formed by a method called α winding.

  Specifically, in order to make an air core, as shown in FIG. 2A, an iron core 40 called an oval type is prepared, and one of the cross sections of the rectangular wire 30 is provided around the iron core 40. It circulates so that the surface of the long side is in contact, and the rectangular wire 30 is repeatedly circulated so as to overlap with the circulated rectangular wire 30. That is, it goes around so as to be parallel to the winding axis. At this time, as the flat wire 30, a wire having a length necessary for forming the winding portion 22 and the lead portions 24 </ b> A and 24 </ b> B is used, and the length of each lead portion is subtracted from both ends of the flat wire 30. As shown in FIG. 2 (A), the intermediate point is applied to the iron core 40, and one end is shifted to the left and right (for example, the right side) by half the width of the flat wire 30 and then circulated. The other end portion side is shifted to the left and right (for example, the left side) by half the width of the flat wire 30 and then circulated. With respect to the direction of circulation, each of the circumferences 22A and 22B having the opposite circulation directions is formed continuously by turning around the iron core 40 in the opposite direction (FIGS. 2 (B) and (B)). C)).

  Next, leading portions 24 </ b> A and 24 </ b> B are formed at both ends of the circumferential portion 22. Bending is performed from the terminal ends 23A and 23B of the winding portion 22 in the direction of one short side (for example, the short side 30A) of the cross section of the rectangular wire 30. At this time, as shown in FIG. 1 (C), a cross section of the rectangular wire 30 at the terminal ends 23A and 23B of the circulating portion 22 with an R attached between the circulating portions 22A and 22B and the lead portions 24A and 24B, respectively. The angle α formed by the surface of the short side 30A and the surface of the short side 30A of the cross section of the flat wire 30 of the lead portions 24A and 24B is 90 ° or less. Thereby, it is possible to form the lead portions 24A and 24B with high accuracy while suppressing peeling of the coating of the conductive wire.

  Finally, the air-core coil 20 was embedded in the magnetic body 12, and the end portions 26A and 26B of the lead portions 24A and 24B and the terminal electrodes 14 and 16 were connected to form the coil component 10. The magnetic material composing the magnetic body 12 was prepared by kneading alloy magnetic particles and resin, and using a mold, setting the air-core coil 20 and then embedding with the magnetic material.

  In the coil component 10 obtained as described above, since the iron core 40 having an oval cross section is used as the winding axis of the flat wire 30, the coil shaft 28 formed by the rotating portion 22 of the air-core coil 20 is The axial cross section of the coil shaft 28 has an oval shape having a major axis LA and a minor axis LB. The lead portions 24A and 24B are moved away from the coil shaft 28 when viewed from the short axis LB side toward the end portions 26A and 26B of the lead portions 24A and 24B from the terminal ends 23A and 23B of the circulating portion 22. It extends like so. At this time, an angle between the lead portions 24A and 24B and the coil shaft 28 (angle β in FIG. 1B) is preferably 0 to 45 °.

Next, the arrangement of the lead-out portions 24A and 24B when the coil shaft 28 has a shape having a long axis LA and a short axis LB will be described with reference to the following specific example.
<Specific example 1> FIG. 3 shows an air-core coil 20A of the coil component of specific example 1. The product size (coil component 10) has a length L of 2.5 mm, a width W of 2.0 mm and a height H of 1.4 mm. The magnetic material is a mixture of FeSiBC and Fe magnetic particles and epoxy resin. Using. In addition, the air-core coil 20A was made of a rectangular wire with a polyimide coating having a cross-sectional dimension of 0.4 × 0.1 mm, and the number of turns of the rotating portion 22 was 10.5. Further, as the terminal electrodes 14 and 16, Ti is formed to a thickness of about 50 nm by sputtering, and then a conductive paste containing Ag is applied to a thickness of about 30 μm and cured at a temperature of about 200 ° C., respectively. The end portions 26A and 26B of the lead portions 24A and 24B are connected. In the first specific example, the ratio of length to width, L / W = 1.25, and when the dimensional ratio is 1.5 or less in this way, the lead-out portions 24A and 24B are cross sections of the coil shaft 28. It is good to arrange on one end side of the short axis LB. By arranging on one side of the short axis in this way, the dimension of the circumferential portion 22 in the L direction can be increased, and the resistance value is low even when L × W is 2.5 mm × 2.0 mm. Coil parts can be made. By arranging the drawing portion with this dimensional ratio, the thickness of the magnetic body 12 embedding the winding portion and the drawing portion can be made the same thickness, and defects in the magnetic body are less likely to occur.

  <Specific example 2> FIG. 4 shows an air-core coil 20B of the coil component of specific example 2. The product size (coil component 10) has a length L of 2.0 mm, a width W of 1.2 mm, a height H of 1.0 mm, and the magnetic material is a mixture of FeSiBC and Fe magnetic particles and an epoxy resin. Was used. The air-core coil 20 </ b> B uses a rectangular wire 30 with a cross-sectional dimension of 0.3 × 0.06 mm polyimide coating, and the number of turns of the winding portion 22 is 11. The terminal electrodes 14 and 16 were prepared by containing sputtered Ti + conductive paste Ag. In specific example 2, the ratio of length to width, L / W = 1.67, and the dimensional ratio is larger than 1.5. Thus, when the dimension is larger than 1.5, when the lead-out parts 24A and 24B are arranged with the coil shaft 28 sandwiched in the direction of the long axis LA of the cross section, the dimension of the rotating part 22 in the W direction is increased. Even a small chip component such as L × W of 2.0 mm × 1.2 mm can be made to have a low resistance value.

Thus, according to the first embodiment, there are the following effects.
(1) The air core coil 20 embedded in the magnetic body 12 is formed by a rectangular wire 30, and the surface 22 of the air core coil 20 has a surface on one long side of the cross section of the rectangular wire 30. The lead portions 24A and 24B of the air-core coil 20 are turned in parallel to the winding axis (iron core 40), and are directed toward one short side of the rectangular wire cross section of the terminal ends 23A and 23B of the turn portion 22. And is connected to the terminal electrodes 14 and 16 on the surface of the magnetic body 12. For this reason, the space | interval of drawer part 24A, 24B can be reduced, and the small coil component 10 without a useless space can be obtained. In particular, by bending the lead portions 24A and 24B toward one short side of the cross section of the rectangular wire 30, the strength of the lead portions 24A and 24B can be obtained, and the positions of the lead portions 24A and 24B are stabilized. Thus, loosening of the winding portion 22 is suppressed, variation in characteristics (inductance) can be reduced, and connection stability with the terminal electrodes 14 and 16 is also obtained. Thereby, even a small component such as a chip component can stably produce a high-performance component.

(2) By suppressing the bending angle of the lead-out portions 24A and 24B at the terminal ends 23A and 23B of the circulating portion 22 to 90 ° or less, a short circuit defect does not occur without damaging the coating of the rectangular wire 30.
(3) By making the cross section of the coil shaft 28 of the revolving part 22 have a major axis LA and a minor axis LB, the drawing position can be arranged at a necessary position, and the component dimensions can be used effectively.
(4) By setting the extraction direction of the extraction portions 24A and 24B to be the direction away from the circulation portion 22, the extraction portions 24A and 24B are less likely to come into contact with the rotation portion 22, and a short circuit failure does not occur.
(5) The lead-out portions 24A and 24B can reduce the return at the time of bending, have high processing accuracy, can reduce the space of the lead-out portions 24A and 24B, and can increase the circumference portion 22. In addition, the number of processing steps is reduced.
(6) By making the circulating portion 22 into an oval type, the curvature of the conducting wire of the circulating portion 22 can be secured, and the coating of the conducting wire is not peeled off, and even a conducting wire having a particularly large cross-sectional area can be wound.

In addition, this invention is not limited to the Example mentioned above, A various change can be added in the range which does not deviate from the summary of this invention. For example, the following are also included.
(1) The shapes, dimensions, and materials shown in the above embodiments are examples, and may be changed as appropriate.
(2) In the above-described embodiment, the terminal electrodes 14 and 16 are provided on the bottom surface of the coil component 10, but this is also an example and can be appropriately changed as necessary.
(3) The dimensions shown in the specific examples are also examples, and the design can be changed as appropriate within a range where the same effects can be obtained. Moreover, the number of turns of the winding part of the air-core coil is also an example, and may be appropriately increased or decreased as necessary.
(4) In the above embodiment, the cross-sectional shape of the air-core coil 20 is an oval type, but this is also an example, and even if it is a polygon such as an octagon or a quadrangle, it has a shape with rounded corners. I just need it. For example, by providing a curvature that is about three times the width of the conducting wire, a winding that exhibits the same effect can be obtained.

  According to the present invention, the air-core coil embedded in the magnetic body is formed by a flat wire, and the circumferential portion of the air-core coil has a surface on one long side of the cross-section of the flat wire as a winding axis. The lead portion of the air-core coil is bent toward one short side of the cross section of the rectangular wire at the end of the loop portion and connected to the terminal electrode on the surface of the magnetic body. For this reason, since it can reduce in size by reducing the space of a drawer part, it can apply to the use of a coil component. In particular, by bending the drawing portion toward one short side of the cross section of the rectangular wire, the strength of the drawing portion can be obtained, and the winding portion can be prevented from loosening by stabilizing the position of the drawing portion. Since variation in characteristics (inductance) can be reduced and connection stability with the terminal electrode can be obtained, it is suitable for high performance coil parts.

10: Coil parts 12: Magnetic bodies 14, 16: Terminal electrodes 20, 20A, 20B: Air-core coils 22, 22A, 22B: Circumferential portions 23A, 23B: Terminal portions 24A, 24B: Lead portions 26A, 26B: End portions 28: Coil axis 30: Rectangular wire 30A, 30B: Short side 30C, 30D: Long side 40: Iron core LA: Long axis LB: Short axis

Claims (9)

A coil component in which an air-core coil is embedded in a magnetic material,
The air-core coil is
Using a rectangular wire having a long side and a short side in the cross section of the conducting wire, a circulating portion that is rotated in the opposite direction from the intermediate portion of the length of the rectangular wire toward both ends, and a terminal electrode on the surface of the magnetic body Has a drawer part to pull out to
The winding portion is wound so that a surface on one long side of the cross section of the rectangular wire is parallel to the winding axis,
The coil component, wherein the lead-out portion is bent toward one short side of a cross section of a rectangular wire at a terminal end of the winding portion.   2. The coil component according to claim 1, wherein the lead portion is bent at an angle of 90 ° or less with respect to a rectangular wire at a terminal end of the winding portion. The coil axis is formed by a circular portion of the air-core coil, and a cross section perpendicular to the axial direction of the coil axis has a shape having a major axis and a minor axis. The coil component described. Characterized in that in a cross section perpendicular to the axial direction of the coil axis, wherein the lead portion is directed Cow direction to an end portion of the lead portion terminating as a starting point of the rounding part is a direction away from the coil axis The coil component according to claim 3. In a cross section perpendicular to the axial direction of the coil axis, the direction of the lead-out portion toward the end of the lead-out portion starting from the end of the turn- around portion is 0 to the outer peripheral surface of the turn- around portion. The coil component according to claim 4, wherein the coil component has an angle of 45 °. The cross-section perpendicular to the axial direction of the coil axis is such that the terminal end of each of the drawn portions is arranged on one side in the short axis direction. The coil component according to one item. 6. The cross section perpendicular to the axial direction of the coil axis, the terminal end of each of the lead portions is arranged with the coil axis sandwiched in the major axis direction. The coil component according to any one of the above. 8. The coil shaft is formed by a revolving portion of the air-core coil, and a cross section perpendicular to the axial direction of the coil shaft is an oval type. Coil parts.   An electronic apparatus comprising the coil component according to claim 1.

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