Manufacturing method for coil components

Abstract

To uniformly and appropriately apply a resin material around a coil round part.SOLUTION: A method for manufacturing a coil component includes the steps of: preparing a core 10 having a winding core part 12 and flange parts 14 and 16 provided on an end in an extension direction of the winding core part 12; winding a lead wire 40 around the winding core part 12, and forming a coil round part 42 composed of the lead wire 40; and bringing the resin material 70 into contact with the periphery of the coil round part 42 and forming a resin part 48 while rotating the coil round part 42 around the winding core part 12.SELECTED DRAWING: Figure 2

Description

Technical Field

[0004] , , , ,

[0005] , , ,

[0001] The present invention relates to a method for manufacturing a coil component.

Background Art

[0002] There is known a coil component in which a coil winding portion is formed on a bobbin portion of a core, and a resin portion is formed around the coil winding portion. As a method for forming the resin portion, resin paste is screen-printed on one surface of a pallet on which the coil component is arranged, and then the pallet is inverted and the resin paste is screen-printed on the other surface, whereby the resin portion is formed around the coil winding portion (for example, Patent Document 1). Also, after fixing the outer bottom surface of one flange portion of the core to a holder, a protective sheet is abutted against the inner bottom surface of the flange portion, and then the core is immersed in liquid resin, whereby the resin portion is formed around the coil winding portion (for example, Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

[0006] The present invention comprises the steps of: preparing a core having a winding core portion and a flange portion provided at the end of the winding core portion in the extension direction; winding a conductor around the winding core portion to form a coil circumference portion made of the conductor; and rotating the coil circumference portion around the winding core portion. 、 The process includes a step of forming a resin part by bringing a resin material into contact with the coil circumference. The step of forming the resin portion includes applying the resin material to only a first portion of the area around the coil circumference by bringing the resin material into contact with the first portion, then removing the resin material from the area around the coil circumference, and then applying the resin material to a second portion of the area around the coil circumference other than the first portion by bringing the resin material into contact with the second portion. This is a method for manufacturing coil components.

[0008] In the above configuration, the resin portion can be formed by the resin material, which is provided on the outer circumference of a disk that rotates on a second rotation axis substantially parallel to the first rotation axis of the coil circumference, coming into contact with the coil circumference.

[0009] In the above configuration, the width dimension of the resin material provided on the outer circumference of the disc in the stretching direction can be made smaller than the length dimension of the core portion in the stretching direction.

[0010] In the above configuration, at the position where the coil circumference and the resin material are in contact, the coil circumference rotates in the same direction relative to the rotation of the disk, and the peripheral velocity of the outer circumference of the coil circumference relative to the outer circumference of the disk is approximately the same as the peripheral velocity of the outer circumference of the disk.

[0011] In the above configuration, at the position where the coil circumference and the resin material are in contact, the coil circumference rotates in the same direction relative to the rotation of the disk, and the peripheral velocity of the outer circumference of the coil circumference relative to the outer circumference of the disk can be configured to be faster than the peripheral velocity of the outer circumference of the disk.

[0012] In the above configuration, at the position where the coil circumference and the resin material are in contact, the coil circumference rotates in the same direction relative to the rotation of the disk, and the peripheral velocity of the outer circumference of the coil circumference relative to the outer circumference of the disk can be configured to be slower than the peripheral velocity of the outer circumference of the disk.

[0013] In the above configuration, at the position where the coil circumference and the resin material come into contact, the coil circumference rotates in a direction opposite to the rotation of the disk, and the peripheral velocity of the outer circumference of the coil circumference relative to the outer circumference of the disk can be configured to be slower than the peripheral velocity of the outer circumference of the disk.

[0014] In the above configuration, the coil circumference revolves around a third rotation axis substantially parallel to the first rotation axis of the coil circumference, and the resin portion is formed by the resin material coming into contact with the coil circumference while the coil circumference revolves and rotates. [Effects of the Invention]

[0015] According to the present invention, a resin material can be applied evenly and in an appropriate amount around the coil circumference. [Brief explanation of the drawing]

[0016] [Figure 1] Figures 1(a) to 1(c) are diagrams (part 1) illustrating a method for manufacturing a coil component according to the first embodiment. [Figure 2] Figures 2(a) to 2(c) are diagrams (part 2) showing a method for manufacturing a coil component according to the first embodiment. [Figure 3] Figures 3(a) and 3(b) are diagrams (part 3) illustrating a method for manufacturing a coil component according to the first embodiment. [Figure 4] Figure 4 is a cross-sectional view showing the relationship between the length of the core's winding portion and the width of the resin material provided on the outer circumference of the disc. [Figure 5]Figs. 5(a) to 5(c) are side views showing a method of applying a resin material around the coil winding portion in Modifications 1 to 3 of the first embodiment. [Figure 6] Figs. 6(a) and 6(b) are side views showing a method of applying a resin material when the cross-sectional shape of the core portion is rectangular. [Figure 7] Fig. 7 is a cross-sectional view showing a method of applying a resin material around the coil winding portion in the second embodiment.

Embodiments for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present invention will be described with appropriate reference to the drawings. However, the present invention is not limited to the illustrated aspects. In addition, the same reference numerals are given to common components in a plurality of drawings. Note that each drawing is not necessarily drawn to an exact scale for the sake of convenience of explanation.

[0018] [First Embodiment] FIG. 1(a) to FIG. 1(c), FIG. 2(a) to FIG. 2(c), FIG. 3(a), and FIG. 3(b) are diagrams showing a method for manufacturing a coil component according to the first embodiment. FIG. 1(a) is a cross-sectional view showing the step of preparing the core 10, and FIG. 1(b) is a plan view seen from the A direction in FIG. 1(a). In FIG. 1(b), the bobbin portion 12 is shown by a dotted line. FIG. 1(c) is a cross-sectional view after the formation of the coil winding portion 42. FIG. 2(a) is a side view showing a method of applying the resin material 70 around the coil winding portion 42 in the first embodiment, FIG. 2(b) is an enlarged view of the core 10 in the region A in FIG. 2(a), and FIG. 2(c) is an enlarged view of the core 10 in the region B in FIG. 2(a). In FIGS. 2(b) and 2(c), the flange portion 16 is shown in perspective to illustrate the bobbin portion 12, the coil winding portion 42, and the resin material 70. FIG. 3(a) is a side view showing a method of applying the resin material 70 around the coil winding portion 42 in the first embodiment. In FIG. 3(a), the flange portion 16 is shown in perspective to illustrate the bobbin portion 12, the coil winding portion 42, and the resin material 70. Also, in FIGS. 2(a) to FIG. 2(c) and FIG. 3(a), for clarity of the figure, the resin material 70 is hatched. FIG. 3(b) is a cross-sectional view of the coil component in which the resin portion 48 is formed. In the present first embodiment, as an example, the case of a drum core having the flange portions 14 and 16 at both ends of the bobbin portion 12 as the core 10 is shown, but the case of a T-core having the flange portion only at one end of the bobbin portion 12 may also be used. The coil component may be a power inductor incorporated in a power line, an inductor used in a signal line, or others.

[0019] As shown in FIGS. 1(a) and 1(b), a core 10, which is a drum core having a bobbin portion 12 extending in the Z-axis direction, one flange portion 14 provided at the -Z side end of the bobbin portion 12, and the other flange portion 16 provided at the +Z side end, is prepared. Two groove portions 20 may be provided on the outer surface 18 of the flange portion 14 opposite to the inner surface to which the bobbin portion 12 is connected. The two groove portions 20 may extend substantially parallel to each other and open to the opposing outer peripheral surface of the flange portion 14.

[0020] Core 10 is formed by, for example, filling a mold cavity with granules of a mixture of magnetic powder and resin and press-molding a molded body, and then performing a heat treatment on this molded body at, for example, around 200°C to solidify the resin. The magnetic powder can be, for example, ferrite magnetic powder or metallic magnetic powder. Examples of ferrite magnetic powder include ferrite materials such as Ni-Zn or Mn-Zn. Examples of metallic magnetic powder include soft magnetic alloy materials such as Fe-Si-Cr, Fe-Si-Al, or Fe-Si-Cr-Al, magnetic metal materials such as Fe or Ni, amorphous magnetic metal materials, or nanocrystalline magnetic metal materials. The resin can be, for example, a resin with excellent insulating properties such as polyvinyl butyral (PVB) resin or epoxy resin.

[0021] The core 10 may also be formed by processing a large block of molded material to create a molded body having a core portion 12 and flange portions 14 and 16, and then performing heat treatment on this molded body. The heat treatment may be performed before or after processing the molded body having the core portion 12 and flange portions 14 and 16. Furthermore, the core 10 is not limited to being formed by solidifying magnetic powder with resin, but may also be formed by bonding magnetic powders together with an inorganic material. In this case, the core 10 is formed by performing heat treatment on a molded body formed by press molding of magnetic powder to, for example, a temperature of about 600°C to 1100°C. Also, the core 10 is not limited to being a magnetic material, but may be a non-magnetic material formed from aluminum oxide (alumina) or silicon oxide (glass), etc.

[0022] The cross-sectional shape of the core portion 12 parallel to the XY plane is, for example, circular. The cross-sectional shape of the flange portions 14 and 16 parallel to the XY plane is, for example, roughly rectangular. The flange portions 14 and 16 are, for example, plate-shaped with thickness in the Z-axis direction. The core portion 12 is smaller than the outer shape of the flange portions 14 and 16 when viewed in the Z-axis direction, and is located near the center of the flange portions 14 and 16. The length dimensions of the core 10 in the X-axis direction, the Y-axis direction, and the Z-axis direction are set appropriately as needed.

[0023] As shown in Figure 1(c), after preparing the core 10, a metal film 30 is formed on the outer surface 18 of the flange portion 14. If a groove 20 is formed on the outer surface 18 of the flange portion 14, the metal film 30 is formed on the inner surface of the groove 20. The metal film 30 is formed by forming a metal film such as copper (Cu) or silver (Ag) by, for example, sputtering or by applying a conductive paste. The metal film 30 is not limited to a single layer of metal, but may also be a multi-layer metal film with a plating layer formed on top of the metal layer using a plating method. The metal film 30 may have an adhesion layer such as titanium (Ti) or chromium (Cr) for adhesion to the flange portion 14.

[0024] After forming the metal film 30, the conductor 40 is wound around the core portion 12 of the core 10 to form a coil circumference portion 42 made of the conductor 40. The conductor 40 is pulled out from each of the pair of ends of the coil circumference portion 42 beyond the flange portion 14, and then the conductor 40 is bent so that the ends 44 of the conductor 40 are positioned on the outer surface 18 of the flange portion 14. If the metal film 30 is formed on the inner surface of the groove portion 20, the ends 44 of the conductor 40 are pulled into the groove portion 20 so that they are positioned on the metal film 30.

[0025] The coil circumference 42 may be wound around the core 12 in a single layer, or it may be wound in multiple layers, either partially or entirely. The conductor 40 is a metal wire, for example made of copper, with its circumference covered by an insulating coating made of urethane. The metal wire may be made of a metal other than copper. The insulating coating may be made of an insulating material other than urethane, such as polyimide, polyamide-imide, or a resin material such as polyester. The cross-sectional shape of the metal wire is, for example, circular, but it may also be rectangular.

[0026] As shown in Figures 2(a) to 2(c), the core 10, on which the coil circumference 42 is formed, is installed on a disc-shaped rotating jig 50 in a state where it is capable of rotation. The cores 10 are installed along the circumference of the rotating jig 50 at predetermined intervals (for example, at regular intervals). The cores 10 can be installed on the rotating jig 50 in any manner as long as the cores 10 are capable of rotation. For example, the cores 10 can be installed on the rotating jig 50 via a member provided on the rotating jig 50 that can rotate on the rotating jig 50, or in any other way as long as the cores 10 are capable of rotation.

[0027] The core 10 rotates around the winding core 12. As a result, the coil circumference 42 formed around the winding core 12 also rotates around the winding core 12. The first axis of rotation 52 of the core 10 and the coil circumference 42 substantially coincides with the central axis of the winding core 12. The direction of rotation of the core 10 and the coil circumference 42 is indicated by arrows 56.

[0028] The rotating jig 50 rotates on its own axis about the third rotation axis 54. Therefore, the core 10 and coil circumference 42, which are fixed to the circumference of the rotating jig 50, revolve around the third rotation axis 54. The third rotation axis 54 and the first rotation axis 52 are approximately parallel. The direction of revolution of the core 10 and coil circumference 42 (i.e., the direction of rotation of the rotating jig 50) is indicated by arrow 58.

[0029] Next to the rotating jig 50, a coating device 60 for applying resin material 70 is provided. The coating device 60 comprises a resin material tank 62 filled with liquid resin material 70, and a disc 64 that rotates on a second rotation axis 66, thereby supplying the resin material 70 from the resin material tank 62 onto its outer circumference 68. The second rotation axis 66 of the disc 64 is approximately parallel to the first rotation axis 52 of the rotation of the core 10 and the coil circumference 42, and the third rotation axis 54 of the rotating jig 50. The direction of rotation of the disc 64 is indicated by arrow 72.

[0030] The resin material 70 is a resin with excellent insulating properties, preferably a thermosetting resin, and may include, for example, epoxy resin or polyimide resin. The resin material 70 may also contain magnetic material fillers, such as magnetic particles with an average particle size of 30 μm or less. For example, the resin material 70 may be a mixture of ferrite magnetic particles at a concentration of 40 vol% or less and epoxy resin at a concentration of 60 vol% or more as fixed components. Furthermore, the resin material 70 may contain non-magnetic material fillers such as silica particles, or it may be a combination of magnetic and non-magnetic materials, or it may contain solvents, etc.

[0031] The disc 64 is movable in parallel towards and away from the rotating jig 50. The directions in which the disc 64 can move are indicated by arrows 74. When applying the resin material 70 around the coil circumference 42, the disc 64 moves towards the rotating jig 50. As a result, the resin material 70 on the outer circumference 68 of the disc 64 comes into contact with the coil circumference 42, and the resin material 70 is applied around the coil circumference 42.

[0032] For example, the rotation period of the coil circumference 42 around the first rotation axis 52 and the revolution period around the third rotation axis 54 may be appropriately set so that when the coil circumference 42 reaches the coating position by the coating device 60 through its revolution, the resin material 70 is applied to a part of the area around the coil circumference 42 (see Figure 2(b)), and when it completes one rotation and returns to the coating position, the resin material 70 is applied to the remaining part or all of it (see Figure 2(c)). Alternatively, for example, the rotating jig 50 may rotate by a predetermined angle using a stepping motor or the like, stop for a predetermined time, and then rotate by the predetermined angle, repeating this process. In this case, when the coil circumference 42 reaches the coating position by the coating device 60 through its revolution, the resin material 70 is applied to a part of the area around the coil circumference 42 (see Figure 2(a)). Alternatively, while the coil circumference 42 rotates once in place without revolving, the disc 64 moves in the direction of arrow 74, combining movements toward and away from the coil circumference 42 to apply the resin material 70. In other words, in Figure 2(a), when the core 10 reaches the position of region B, the revolution stops for a predetermined time, and while the revolution is stopped, the coil circumference 42 rotates once, and as in Figures 2(b) and 2(c), the disc 64 moves in the direction of arrow 74 to apply the resin material 70 around the coil circumference 42. In this way, the resin material 70 is applied around the coil circumference 42 by the resin material 70 contacting the coil circumference 42 multiple times.

[0033] Furthermore, when providing the resin material 70 to the disc 64, the thickness of the resin material 70 on the outer circumference of the disc 64 may be adjusted to be thinner by a mechanism for adjusting the thickness of the resin material 70 provided in part of the coating device 60. In this way, the thickness of the resin material 70 provided on the outer circumference of the disc 64 can be made thin and uniform.

[0034] As shown in Figure 3(a), the coil circumference 42 rotates in the direction of arrow 56 about the first rotation axis 52. The disk 64 of the coating device 60 rotates in the direction of arrow 72 about the second rotation axis 66. As a result, the resin material 70 on the outer circumference 68 of the disk 64 is applied evenly and in an appropriate amount around the coil circumference 42.

[0035] In this first embodiment, the rotation direction of the coil circumference portion 42 is clockwise, and the rotation direction of the disk 64 is counterclockwise. Therefore, at the point where the coil circumference portion 42 and the resin material 70 on the outer circumference 68 of the disk 64 come into contact, the coil circumference portion 42 rotates in the same direction relative to the disk 64. Also, in this first embodiment, the relative peripheral velocity of the outer circumference of the coil circumference portion 42 with respect to the outer circumference of the disk 64 is approximately the same as the peripheral velocity of the outer circumference of the disk 64. In this case, when the coil circumference portion 42 comes into contact with the resin material 70 on the outer circumference 68 of the disk 64, an amount of resin material 70 corresponding to the amount of resin material 70 on the outer circumference 68 of the disk 64 is applied to the coil circumference portion 42.

[0036] As shown in Figure 3(b), a resin material 70 is applied around the coil circumference 42, and then the resin material 70 is cured to form a resin portion 48 that covers the periphery of the coil circumference 42. Preferably, the resin portion 48 covers the entire coil circumference 42, but it is sufficient if it covers 90% or more, and more preferably if it covers 95% or more. After forming the resin portion 48, a solder film 32 is applied to the surface of the metal film 30, and the metal wire at the end 44 of the conductor 40 is joined to the metal film 30 and the solder film 32 to form an external electrode 34 that is electrically connected to the coil circumference 42. Thus, the coil component according to the first embodiment is formed. Note that the external electrode 34 may be formed before forming the resin portion 48.

[0037] As described above, according to this first embodiment, as shown in Figures 2(a) to 3(b), the resin material 70 is brought into contact with the coil circumference 42 while the coil circumference 42 is rotated around the winding core 12, thereby forming the resin portion 48. In this way, by rotating the coil circumference 42 around the winding core 12 while bringing the resin material 70 into contact with it, the resin material 70 can be applied evenly and in an appropriate amount around the coil circumference 42. As a result, a resin portion 48 of uniform thickness is formed around the coil circumference 42.

[0038] Furthermore, according to this first embodiment, as shown in Figures 2(a) to 2(c), the resin portion 48 is formed by the resin material 70 coming into contact with the coil circumference portion 42 multiple times. This makes it easier for the resin material 70 to be applied evenly and in an appropriate amount around the coil circumference portion 42, and makes it easier to form a resin portion 48 of uniform thickness around the coil circumference portion 42. In order to ensure that the resin material 70 is applied evenly and in an appropriate amount around the coil circumference portion 42, it is preferable that the resin material 70 comes into contact with the coil circumference portion 42 many times, for example, three times or more is preferable, four times or more is more preferable, and six times or more is even more preferable.

[0039] Furthermore, according to this first embodiment, as shown in Figures 2(a) to 3(b), the resin portion 48 is formed when a resin material 70 provided on the outer circumference 68 of a disk 64 that rotates around a second rotation axis 66 which is substantially parallel to the first rotation axis 52 of the coil circumference portion 42 comes into contact with the coil circumference portion 42. This allows the amount of resin material 70 applied to the coil circumference portion 42 to be controlled by adjusting the amount of resin material 70 provided on the outer circumference 68 of the disk 64 and the rotation speed of the coil circumference portion 42 and / or the disk 64. As a result, an appropriate amount of resin material 70 is easily applied around the coil circumference portion 42. "Substantially parallel" means that a deviation of the magnitude of manufacturing tolerance is allowed, and the inclination angle of the second rotation axis 66 with respect to the first rotation axis 52 is 2° or less.

[0040] Furthermore, according to this first embodiment, as shown in Figure 3(a), at the point where the coil circumference portion 42 and the resin material 70 on the outer circumference 68 of the disk 64 come into contact, the coil circumference portion 42 rotates in the same direction relative to the rotation of the disk 64. The peripheral velocity of the outer circumference of the coil circumference portion 42 relative to the outer circumference of the disk 64 is approximately the same as the peripheral velocity of the outer circumference of the disk 64. As a result, when the coil circumference portion 42 comes into contact with the resin material 70 on the outer circumference 68 of the disk 64, an amount of resin material 70 corresponding to the amount of resin material 70 on the outer circumference 68 of the disk 64 is applied to the coil circumference portion 42. Therefore, by adjusting the amount of resin material 70 on the outer circumference 68 of the disk 64, the amount of resin material 70 applied around the coil circumference portion 42 can be controlled. Approximately the same peripheral velocity means that a deviation of the magnitude of control error is allowed, and this is when the peripheral velocity of the coil circumference portion 42 is 98% or more and 102% or less relative to the peripheral velocity of the disk 64.

[0041] Furthermore, according to this first embodiment, as shown in Figures 2(a) to 2(c), the coil circumference 42 revolves around a third rotation axis 54 that is substantially parallel to the first rotation axis 52 of the coil circumference 42's rotation. The resin part 48 is formed when the resin material 70 comes into contact with the coil circumference 42 while the coil circumference 42 revolves around the third rotation axis 54 and rotates around the first rotation axis 52. This makes it possible to form the resin part 48 by sequentially applying the resin material 70 around the coil circumference 42 of multiple cores 10. "Substantially parallel" means that a deviation of the magnitude of manufacturing tolerance is allowed, and this is when the inclination angle of the third rotation axis 54 with respect to the first rotation axis 52 is 2° or less.

[0042] Figure 4 is a cross-sectional view showing the relationship between the length of the core portion 12 of the core 10 and the width of the resin material 70 provided on the outer circumference 68 of the disc 64. As shown in Figure 4, the width dimension W of the resin material 70 provided on the outer circumference 68 of the disc 64 in the stretching direction (Z-axis direction) of the core portion 12 is smaller than the length dimension L of the core portion 12 in the stretching direction (Z-axis direction). This allows the resin material 70 to be selectively applied around the coil circumference 42, and prevents the resin material 70 from adhering to the flange portions 14 and 16. The width dimension W of the resin material 70 is preferably 80% to 95% of the length dimension L of the core portion 12, more preferably 85% to 95%, and even more preferably 90% to 95%.

[0043] [Differentiation] In the first embodiment described above, the coil circumference portion 42 rotates in the same direction relative to the disk 64 at the point where it contacts the resin material 70 on the outer circumference 68 of the disk 64, and the case shown as an example where the peripheral velocity of the outer circumference of the coil circumference portion 42 relative to the outer circumference of the disk 64 is approximately the same as the peripheral velocity of the outer circumference of the disk 64. However, other cases will be described in the modified examples.

[0044] Figure 5(a) is a side view showing a method for applying resin material 70 around the coil circumference 42 in Modification 1 of the first embodiment. As shown in Figure 5(a), in this Modification 1, the coil circumference 42 rotates in the same direction relative to the disk 64 at the position where the coil circumference 42 and the resin material 70 on the outer circumference 68 of the disk 64 come into contact, which is the same as in the first embodiment. However, it differs from the first embodiment in that the relative peripheral velocity of the outer circumference of the coil circumference 42 with respect to the outer circumference of the disk 64 is faster than the peripheral velocity of the outer circumference of the disk 64.

[0045] As shown in this Modification 1, when the coil circumference 42 rotates in the same direction relative to the rotation of the disk 64 at the point where it contacts the resin material 70 on the outer circumference 68 of the disk 64, the relative peripheral speed of the outer circumference of the coil circumference 42 with respect to the outer circumference of the disk 64 is faster than the peripheral speed of the outer circumference of the disk 64, resulting in a reduced amount of resin material 70 being applied around the coil circumference 42. For example, even without changing the amount of resin material 70 on the outer circumference 68 of the disk 64 from the first embodiment, the amount of resin material 70 applied around the coil circumference 42 can be reduced by simply increasing the peripheral speed of the coil circumference 42. This Modification 1 is suitable when it is desired to reduce the amount of resin material 70 applied around the coil circumference 42. The relative peripheral speed of the outer circumference of the coil circumference 42 is faster than the peripheral speed of the outer circumference of the disk 64 if the relative peripheral speed of the outer circumference of the coil circumference 42 is 1.5 times or more than the peripheral speed of the outer circumference of the disk 64, and may also be 1.8 times or more, or 2 times or more.

[0046] Figure 5(b) is a side view showing a method for applying the resin material 70 around the coil circumference 42 in a modified example 2 of the first embodiment. As shown in Figure 5(b), in this modified example 2, the coil circumference 42 rotates in the same direction relative to the disk 64 at the point where it contacts the resin material 70 on the outer circumference 68 of the disk 64, just like in the first embodiment. However, it differs from the first embodiment in that the relative peripheral speed of the outer circumference of the coil circumference 42 with respect to the outer circumference of the disk 64 is slower than the peripheral speed of the outer circumference of the disk 64.

[0047] As shown in this Modified Example 2, when the coil circumference 42 rotates in the same direction relative to the rotation of the disk 64 at the point where it contacts the resin material 70 on the outer circumference 68 of the disk 64, the relative peripheral speed of the outer circumference of the coil circumference 42 with respect to the outer circumference of the disk 64 is slower than the peripheral speed of the outer circumference of the disk 64, resulting in a larger amount of resin material 70 being applied around the coil circumference 42. For example, even without changing the amount of resin material 70 on the outer circumference 68 of the disk 64 from the first embodiment, the amount of resin material 70 applied around the coil circumference 42 can be increased by simply slowing down the peripheral speed of the coil circumference 42. This Modified Example 2 is suitable when it is desired to increase the amount of resin material 70 applied around the coil circumference 42. For example, even if the cross-sectional shape of the winding core 12 is rectangular, the increased amount of resin material 70 makes it easier to apply the resin material 70 evenly around the coil circumference 42. The relative peripheral speed of the outer circumference of the coil circumference 42 is slower than the peripheral speed of the outer circumference of the disk 64 if the relative peripheral speed of the outer circumference of the coil circumference 42 is 0.7 times or less the peripheral speed of the outer circumference of the disk 64, and may also be 0.5 times or less, or 0.3 times or less.

[0048] Figure 5(c) is a side view showing a method for applying the resin material 70 around the coil circumference 42 in Modification 3 of the first embodiment. As shown in Figure 5(c), in this Modification 3, the coil circumference 42 rotates in opposite directions relative to the disk 64 at the position where the coil circumference 42 and the resin material 70 on the outer circumference 68 of the disk 64 come into contact, and differs from the first embodiment in that the relative peripheral velocity of the outer circumference of the coil circumference 42 with respect to the outer circumference of the disk 64 is slower than the peripheral velocity of the outer circumference of the disk 64.

[0049] As shown in this modified example 3, at the point where the coil circumference portion 42 and the resin material 70 on the outer circumference 68 of the disk 64 come into contact, the coil circumference portion 42 rotates in the opposite direction relative to the rotation of the disk 64. As a result, the relative peripheral speed of the outer circumference of the coil circumference portion 42 to the outer circumference of the disk 64 is slower than the peripheral speed of the outer circumference of the disk 64, which increases the amount of resin material 70 applied around the coil circumference portion 42. For example, even without changing the amount of resin material 70 on the outer circumference 68 of the disk 64 from the first embodiment, the amount of resin material 70 applied around the coil circumference portion 42 can be increased by changing the rotation direction of the coil circumference portion 42 and slowing down its peripheral speed. This modified example 3 is suitable when it is desired to increase the amount of resin material 70 applied around the coil circumference portion 42. The relative peripheral speed of the outer circumference of the coil circumference 42 is slower than the peripheral speed of the outer circumference of the disk 64 if the relative peripheral speed of the outer circumference of the coil circumference 42 is 0.7 times or less the peripheral speed of the outer circumference of the disk 64, and may also be 0.5 times or less, or 0.3 times or less.

[0050] In the first embodiment and its modifications described above, the case where the cross-sectional shape of the winding core 12 is circular is shown as an example, but other cases such as a rectangle are also possible. In the case of a rectangle, the corners may be chamfered and rounded. Figures 6(a) and 6(b) are side views showing a method of applying the resin material 70 when the cross-sectional shape of the winding core 12 is rectangular. As shown in Figure 6(a), when the cross-sectional shape of the winding core 12 is close to a square, the period of rotation of the coil circumference 42 around the first rotation axis 52 and the period of revolution around the third rotation axis 54 (see Figure 2(a)) may be appropriately set, and the resin material 70 may be applied in four separate steps to the locations corresponding to each side of the rectangle. Alternatively, while the coil circumference 42 rotates once in place without revolving, the disc 64 may move in the direction of the arrow 74, combining movements of approaching and moving away from the coil circumference 42, and the resin material 70 may be applied in four separate steps to the locations corresponding to each side of the rectangle.

[0051] As shown in Figure 6(b), if the cross-sectional shape of the core 12 is an elongated rectangle, the period of rotation of the coil circumference 42 around the first rotation axis 52 and the period of revolution around the third rotation axis 54 (see Figure 2(a)) may be appropriately set, and the resin material 70 may be applied in two stages to the parts corresponding to the longer sides of the rectangle. Alternatively, while the coil circumference 42 rotates once in place without revolutionizing, the disc 64 may move in the direction of the arrow 74, combining movements of approaching and moving away from the coil circumference 42, to apply the resin material 70 in two stages to the parts corresponding to the longer sides of the rectangle. Since the shorter sides of the rectangle are short, the applied resin material 70 will wrap around to the shorter sides, so that the resin material 70 is applied around the coil circumference 42.

[0052] When the cross-sectional shape of the core 12 is rectangular, the core 10 rotates around the first rotation axis 52. Therefore, the disk 64 of the coating device 60 is moved in the direction of arrow 74 (see Figure 2(a)), and the resin material 70 is applied around the coil circumference 42 while changing the distance between the disk 64 and the coil circumference 42. In this case, by using a method that increases the amount of resin material 70 applied, as shown in Figures 5(b) and 5(c), the distance the disk 64 moves can be kept small. Thus, the decrease in productivity associated with the movement of the disk 64 can be suppressed.

[0053] [Second Embodiment] In the first embodiment and its modifications described above, an example was shown in which resin material 70 is applied around the coil circumference 42 using a coating device 60 equipped with a resin material tank 62 and a disc 64. In this second embodiment, however, a case in which resin material 70 is applied around the coil circumference 42 using a dispenser device 80 will be described. Since this is the same as the manufacturing method of the coil component according to the first embodiment, except for the method of applying the resin material 70 to the coil circumference 42, the manufacturing process other than the application of the resin material 70 will not be described.

[0054] Figure 7 is a cross-sectional view showing a method for applying resin material 70 around the coil circumference 42 in the second embodiment. As shown in Figure 7, while rotating the coil circumference 42 around the winding core 12, resin material 70 is discharged from a dispensing nozzle 82 provided in the dispenser device 80, bringing the resin material 70 into contact with the coil circumference 42. Then, as shown in Figure 3(b) of the first embodiment, the resin material 70 formed around the coil circumference 42 is cured to form a resin portion 48 that covers the periphery of the coil circumference 42.

[0055] As in this second embodiment, the resin material 70 may be applied to the coil circumference 42 using a dispenser device 80. Even when applying the resin material 70 using a commonly available dispenser device 80, the resin material 70 can be applied evenly and in an appropriate amount around the coil circumference 42 by rotating the coil circumference 42 around the winding core 12 and bringing the resin material 70 into contact with the area around the coil circumference 42.

[0056] Although embodiments of the present invention have been described in detail above, the present invention is not limited to these specific embodiments, and various modifications and changes are possible within the scope of the gist of the present invention as described in the claims. [Explanation of symbols]

[0057] 10 cores 12-winding core section 14, 16 Guard section 18 Exterior 20 grooves 30 Metal film 32 Solder film 34 External electrode 40 Conductor 42 Coil surrounding section 44 End of the conductor 48 Resin part 50 Rotating fixtures 52. First rotation axis 54 Third rotation axis 60 Coating device 62 Resin material tank 64 disks 66 Second rotation axis 68 Outer perimeter 70 Resin materials 80 Dispenser device 82 Dispensing Nozzles

Claims

1. A step of preparing a core having a winding core portion and a flange portion provided at the end of the winding core portion in the extension direction, The process of winding a conductor around the aforementioned core to form a coil circumference made of the conductor, The process includes rotating the coil circumference around the winding core and bringing a resin material into contact with the coil circumference to form a resin portion, A method for manufacturing a coil component, comprising the step of forming the resin portion, which includes contacting the resin material only with a first portion of the area around the coil circumference to apply the resin material to the first portion, then separating the resin material from the area around the coil circumference, and then contacting the resin material with a second portion of the area around the coil circumference other than the first portion to apply the resin material to the second portion.

2. The method for manufacturing a coil component according to claim 1, wherein the resin portion is formed by the resin material provided on the outer circumference of a disk that rotates about a second rotation axis substantially parallel to the first rotation axis of the coil circumference, and the resin material comes into contact with the coil circumference.

3. The method for manufacturing a coil component according to claim 2, wherein the width dimension of the resin material provided on the outer circumference of the disc in the stretching direction is smaller than the length dimension of the core portion in the stretching direction.

4. At the position where the coil circumference and the resin material come into contact, the coil circumference rotates in the same direction relative to the rotation of the disc. The method for manufacturing a coil component according to claim 2 or 3, wherein the relative peripheral velocity of the outer circumference of the coil circumferential portion with respect to the outer circumference of the disk is substantially the same as the peripheral velocity of the outer circumference of the disk.

5. At the position where the coil circumference and the resin material come into contact, the coil circumference rotates in the same direction relative to the rotation of the disc. The method for manufacturing a coil component according to claim 2 or 3, wherein the relative peripheral velocity of the outer circumference of the coil circumferential portion with respect to the outer circumference of the disk is faster than the peripheral velocity of the outer circumference of the disk.

6. At the position where the coil circumference and the resin material come into contact, the coil circumference rotates in the same direction relative to the rotation of the disc. The method for manufacturing a coil component according to claim 2 or 3, wherein the relative peripheral speed of the outer circumference of the coil circumferential portion with respect to the outer circumference of the disk is slower than the peripheral speed of the outer circumference of the disk.

7. At the position where the coil circumference and the resin material come into contact, the coil circumference rotates in a direction opposite to the rotation of the disc. The method for manufacturing a coil component according to claim 2 or 3, wherein the relative peripheral speed of the outer circumference of the coil circumferential portion with respect to the outer circumference of the disk is slower than the peripheral speed of the outer circumference of the disk.

8. The coil circumference revolves around a third axis of rotation that is substantially parallel to the first axis of rotation of the coil circumference. The method for manufacturing a coil component according to any one of claims 1 to 7, wherein the resin portion is formed by the resin material coming into contact with the coil circumference while the coil circumference rotates and revolves.

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