Coil case, and switching power supply unit

Abstract

To provide a coil case capable of suppressing solder cracks, and a switching power supply unit.SOLUTION: A coil case concerning the disclosure is a coil case for holding a coil. The coil case has a hole into which a terminal of the coil is inserted, which is soldered to the board and includes a terminal hole portion having a slit formed around the hole. The slit is a gap in the coil case.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a coil case and a switching power supply device.

Background Art

[0002] Conventionally, in a power supply device, a coil is housed in a coil case. The coil case has terminal holes into which the terminals of the coil are inserted. Then, the terminals of the coil are soldered to a substrate through the terminal holes.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the coil case is deformed due to thermal expansion or contraction, pressure is applied to the soldered portion between the terminals of the coil and the substrate. Therefore, solder cracks may occur, which break the soldering between the terminals of the coil and the substrate.

[0005] An object of the present disclosure is to provide a coil case and a switching power supply device capable of suppressing solder cracks.

Means for Solving the Problems

[0006] The coil case according to the present disclosure is a coil case that holds a coil, has holes into which the terminals of the coil to be soldered to a substrate are inserted, and includes a terminal hole portion in which slits are formed around the holes. The slits are gaps in the coil case.

Effects of the Invention

[0007] According to the present disclosure, a coil case capable of suppressing solder cracks and a switching power supply device can be provided.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings as appropriate. However, a more detailed description than necessary may be omitted. Note that the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and it is not intended to limit the subject matter described in the claims thereby.

[0010] (First Embodiment) FIG. 1 is a perspective view showing an example of the appearance of the coil case 1 according to the first embodiment as viewed from above. FIG. 2 is a perspective view showing an example of the appearance of the coil case 1 according to the first embodiment as viewed from below. In the present embodiment, a rectangular coordinate system composed of the X-axis, Y-axis, and Z-axis is defined. The X-axis direction is parallel to the longitudinal direction of the coil case 1. The Y-axis direction is parallel to the short-side direction of the coil case 1. The Z-axis direction is perpendicular to the X-axis direction and the Y-axis direction, and is perpendicular to the upper surface 12 of the coil case 1.

[0011] The coil case 1 holds a coil. For example, the coil case 1 is housed in a switching power supply device such as a charger. The switching power supply device includes, for example, a filter circuit, a rectifier circuit, a DC / DC converter, and a smoothing circuit. The filter circuit is a circuit that suppresses noise in the AC power input from an external AC power supply. The rectifier circuit is a circuit that rectifies AC power into DC power. The DC / DC converter is a conversion circuit that converts voltage. The smoothing circuit is a circuit that smooths fluctuations in the output voltage. Also, the DC / DC converter has a coil. For example, the coil of the DC / DC converter is held by the coil case 1.

[0012] The coil case 1 houses a plurality of coils. More specifically, the coil case 1 includes a first coil housing portion 11a, a second coil housing portion 11b, a third coil housing portion 11c, a fourth coil housing portion 11d, a fifth coil housing portion 11e, and a sixth coil housing portion 11f. The first coil housing portion 11a, the second coil housing portion 11b, the third coil housing portion 11c, the fourth coil housing portion 11d, the fifth coil housing portion 11e, and the sixth coil housing portion 11f each house one coil. Hereinafter, when the first coil housing portion 11a, the second coil housing portion 11b, the third coil housing portion 11c, the fourth coil housing portion 11d, the fifth coil housing portion 11e, and the sixth coil housing portion 11f are not distinguished, they are referred to as the coil housing portion 11.

[0013] In addition, the coil case 1 is provided with a first spacing portion 20a, a second spacing portion 20b, a third spacing portion 20c, a fourth spacing portion 20d, a fifth spacing portion 20e, and a sixth spacing portion 20f on the upper surface 12. Hereinafter, when the first spacing portion 20a, the second spacing portion 20b, the third spacing portion 20c, the fourth spacing portion 20d, the fifth spacing portion 20e, and the sixth spacing portion 20f are not distinguished, they are collectively referred to as the coil accommodating portion 11. More specifically, on the upper surface 12 of the coil case 1, each coil accommodating portion 11 has a spacing portion 20. Here, the substrate 2 (see FIG. 5) is placed on the upper surface 12 of the coil case 1. The spacing portion 20 is a cylindrical convex portion for providing a spacing between the upper surface 12 of the coil case 1 and the substrate 2.

[0014] In addition, the coil case 1 is provided with a first protrusion 30a, a second protrusion 30b, a third protrusion 30c, and a fourth protrusion 30d on the upper surface 12. Hereinafter, when the first protrusion 30a, the second protrusion 30b, the third protrusion 30c, and the fourth protrusion 30d are not distinguished, they are collectively referred to as the coil accommodating portion 11. The protrusion 30 is a protrusion disposed on the upper surface 12. A member is placed on the protrusion 30 upward. Thereby, a member can be further disposed above the substrate 2 by the protrusion 30.

[0015] Furthermore, the protrusion 30 transfers the heat of the placed member to the coil side. Here, since the coil generates heat, a member for heat dissipation is disposed in the vicinity. Also, the coil case 1 can dissipate the heat of the coil. Therefore, the protrusion 30 can efficiently cool the placed member by transferring the heat of the placed member to the coil side.

[0016] Further, the coil case 1 is provided with a first planar terminal hole portion 40a, a second planar terminal hole portion 40b, a third planar terminal hole portion 40c, a fourth planar terminal hole portion 40d, a fifth planar terminal hole portion 40e, a sixth planar terminal hole portion 40f, a seventh planar terminal hole portion 40g, and an eighth planar terminal hole portion 40h in a planar portion of the upper surface 12. Hereinafter, when not distinguishing the first planar terminal hole portion 40a, the second planar terminal hole portion 40b, the third planar terminal hole portion 40c, the fourth planar terminal hole portion 40d, the fifth planar terminal hole portion 40e, the sixth planar terminal hole portion 40f, the seventh planar terminal hole portion 40g, and the eighth planar terminal hole portion 40h, they are collectively referred to as the planar terminal hole portion 40.

[0017] Furthermore, the coil case 1 is provided with a first edge terminal hole portion 50a, a second edge terminal hole portion 50b, a third edge terminal hole portion 50c, and a fourth edge terminal hole portion 50d at an edge portion of the coil case 1. Hereinafter, when not distinguishing the first edge terminal hole portion 50a, the second edge terminal hole portion 50b, the third edge terminal hole portion 50c, and the fourth edge terminal hole portion 50d, they are collectively referred to as the edge terminal hole portion 50.

[0018] The planar terminal hole portion 40 has a through hole 41 into which a terminal 3 formed at an end of a lead wire of a coil stored in the coil storage portion 11 is inserted. Similarly, the edge terminal hole portion 50 has a through hole 51 into which a terminal 3 formed at an end of a lead wire of a coil stored in the coil storage portion 11 is inserted. Here, the lead wire of the coil has two ends. Therefore, two planar terminal hole portions 40 or edge terminal hole portions 50 are arranged in each coil storage portion 11.

[0019] FIG. 3 is a perspective view showing an example of the appearance of the planar terminal hole portion 40 according to the first embodiment. The planar terminal hole portion 40 has a through hole 41 into which a terminal 3 of a coil to be soldered to the substrate 2 is inserted, and a slit 42 is formed around the through hole 41.

[0020] More specifically, the planar terminal hole portion 40 has an insertion portion 43 having a through hole 41 into which a terminal 3 of a coil is inserted, and a support portion 44 that supports the insertion portion 43 in a direction perpendicular to the insertion direction of the terminal 3. And a substantially U-shaped slit 42 is formed around the insertion portion 43 and the support portion 44 of the planar terminal hole portion 40.

[0021] The slit 42 is a gap where a part of the coil case 1 is removed. The slit 42 is formed in a substantially U-shape surrounding the insertion portion 43 and the support portion 44. And the slit 42 is not formed at the end of the support portion 44 on the side that does not support the insertion portion 43.

[0022] The insertion portion 43 has a through hole 41 into which the terminal 3 of the coil is inserted. The insertion portion 43 is formed in a substantially circular shape and has the through hole 41 at substantially the center. The through hole 41 is formed in a funnel shape whose outer diameter narrows as it goes from the upper surface 12 toward the inside of the coil case 1.

[0023] One end of the support portion 44 supports the insertion portion 43, and the other end is fixed to the coil case 1. More specifically, the support portion 44 supports the insertion portion 43 from a direction perpendicular to the longitudinal direction of the coil case 1. In other words, the slit 42 is formed so as to surround the insertion portion 43 and sandwich the support portion 44. Here, the degree of volume change due to thermal expansion or thermal contraction is larger in the longitudinal direction than in the short-side direction of the coil case 1. Therefore, by forming the slit 42 in the longitudinal direction of the coil case 1, the pressure applied to the insertion portion 43 can be suppressed.

[0024] Also, the width of the support portion 44 in the direction perpendicular to the longitudinal direction of the coil case 1 is narrower than that of the insertion portion 43. In other words, the length of the support portion 44 in the X-axis direction is narrower than the diameter of the insertion portion 43 formed in a substantially circular shape. Thus, since the support portion 44 is thinner than the insertion portion 43, it is easily deformed when pressure is applied in the X-axis direction or in the direction in which the X-axis direction and the Z-axis direction are combined. Therefore, the support portion 44 can reduce the pressure applied to the portion where the substrate 2 and the terminal 3 are soldered. Thus, the support portion 44 can suppress solder cracks that break the soldering between the substrate 2 and the terminal 3.

[0025] Further, the support portion 44 has a length in a direction perpendicular to the longitudinal direction of the coil case 1 that is longer than the diameter of the insertion portion 43. In other words, the length of the support portion 44 in the Y-axis direction is longer than the diameter of the insertion portion 43 formed in a substantially circular shape. Thus, since the support portion 44 is longer than the diameter of the insertion portion 43, it is easily bent when pressure is applied in the Z-axis direction. Therefore, the support portion 44 can reduce the pressure applied to the portion where the substrate 2 and the terminal 3 are soldered. Thus, the support portion 44 can suppress solder cracks.

[0026] FIG. 4 is a perspective view showing an example of the appearance of the edge terminal hole portion 50 according to the first embodiment. Similar to the planar terminal hole portion 40, the edge terminal hole portion 50 has a through hole 51 into which the terminal 3 of the coil is inserted and that is soldered to the substrate 2, and a slit 52 is formed around the through hole 51. The planar terminal hole portion 40 and the edge terminal hole portion 50 are examples of terminal hole portions.

[0027] More specifically, the edge terminal hole portion 50 has an insertion portion 53 having a through hole 51 into which the terminal 3 of the coil is inserted, and a support portion 54 that supports the insertion portion 53 from a direction perpendicular to the insertion direction of the terminal 3. And a slit 52 is formed around the insertion portion 53 and the support portion 54 of the edge terminal hole portion 50.

[0028] Here, the edge terminal hole portion 50 is disposed at the edge portion of the coil case 1. Therefore, the support portion 54 of the edge terminal hole portion 50 is bent substantially at a right angle along the coil case 1. That is, the support portion 54 extends in the Z-axis direction from the side surface of the coil case 1 and is bent in the Y-axis direction on the upper surface 12 of the coil case 1.

[0029] Also, the insertion portion 53 has the same shape as the insertion portion 43 of the planar terminal hole portion 40. Also, the slit 52 is formed around the insertion portion 53 and the support portion 54. Therefore, the slit 52 is formed on the side surface of the coil case 1 and the upper surface 12 of the coil case 1.

[0030] Here, the coil case 1 deforms due to thermal expansion and contraction. Also, the degree of change in the coil case 1 is greater on the outer side than on the inner side of the upper surface 12. The coil case 1 has a planar terminal hole portion 40 disposed inside the upper surface 12 of the coil case 1 and an edge terminal hole portion 50 disposed outside the planar terminal hole portion 40. And the slit 52 of the edge terminal hole portion 50 is larger than the slit 42 of the planar terminal hole portion 40. The planar terminal hole portion 40 is an example of a first terminal hole portion. The edge terminal hole portion 50 is an example of a second terminal hole portion. Also, the slit 42 of a fourth planar terminal hole portion 40d disposed outside the slit 42 of a third planar terminal hole portion 40c disposed inside the upper surface 12 of the coil case 1 may be larger.

[0031] Next, the case where the terminal 3 of the coil is soldered to the substrate 2 will be described. FIG. 5 is a cross-sectional view showing an example of a state where the terminal 3 is soldered to the substrate 2. Also, FIG. 5 shows a state where the terminal 3 inserted into the planar terminal hole portion 40 is soldered.

[0032] The substrate 2 is placed on the spacing portion 20 formed on the upper surface 12 of the coil case 1. The terminal 3 of the lead wire of the coil is inserted from below upward through the through hole 41 provided in the insertion portion 43 of the planar terminal hole portion 40. The terminal 3 passing through the through hole 41 is soldered to the substrate 2. In other words, the terminal 3 is connected to the wiring of the substrate 2 by the solder 4.

[0033] As shown in FIG. 5, a slit 42 is formed around the insertion portion 43. Even if pressure is applied in the X-axis direction, Y-axis direction, Z-axis direction, or a direction obtained by combining these directions due to thermal expansion and contraction of the coil case 1, the slit 42 can absorb the pressure and suppress solder cracks.

[0034] Also, as shown in FIG. 5, the terminal 3 of the coil is inserted upward from below the through hole 41 and soldered to the substrate 2. The insertion portion 43 having the through hole 41 is held by the support portion 44. One end of the support portion 44 is a fixed end fixed to the coil case 1, but the side where the insertion portion 43 is provided is a free end that is not fixed. Further, the support portion 44 has a width in the X-axis direction that is narrower than the diameter of the insertion portion 43 and a length in the Y-axis direction that is longer than the diameter of the insertion portion 43. Therefore, the support portion 44 is easily bendable. That is, the insertion portion 43 is easily movable within the slit 42. Thus, since the insertion portion 43 moves within the slit 42 according to the pressure, the pressure applied to the soldered portion can be reduced. As a result, the support portion 44 can suppress solder cracks.

[0035] Also, as shown in FIG. 5, the coil case 1 includes a spacer portion 20 that forms a gap between the substrate 2 and the upper surface 12. When the coil case 1 is deformed due to thermal expansion or thermal contraction, the pressure caused by the deformation is absorbed by the gap formed by the spacer portion 20. Thereby, the insertion portion 43 can reduce the pressure applied to the soldered portion. Therefore, the spacer portion 20 can suppress solder cracks.

[0036] As described above, the coil case 1 according to the first embodiment holds the coil. And the coil case 1 has through holes 41 and 51 into which the terminals 3 of the coil are inserted and are soldered to the substrate 2, and includes a planar terminal hole portion 40 and an edge terminal hole portion 50 in which slits 42 and 52 are formed around the through holes 41 and 51. And the planar terminal hole portion 40 and the edge terminal hole portion 50 can reduce the pressure applied to the soldered portion even against the pressure generated by thermal expansion or thermal contraction. Therefore, the coil case 1 can suppress solder cracks.

[0037] (Modification 1) The support portion 44 of the planar terminal hole portion 40 according to the first embodiment described above has been described as being planar. However, the support portion 44 of the planar terminal hole portion 40 is not limited to being planar and may be bent.

[0038] FIG. 6 is a cross-sectional view showing an example of the planar terminal hole portion 40 according to the first modification. Similar to the planar terminal hole portion 40 according to the first embodiment, the planar terminal hole portion 40 includes an insertion portion 63 having a through hole 61, a support portion 64, and a slit 62. The insertion portion 63 and the slit 62 have the same shapes as the insertion portion 43 and the slit 42 of the planar terminal hole portion 40 according to the first embodiment. As shown in FIG. 6, the support portion 64 is curved. Thus, since the support portion 64 is curved, it is easily bendable. Therefore, the support portion 64 can suppress solder cracks. Further, the support portion 64 shown in FIG. 6 is curved upward, but it may be curved not only upward but also to either the left or right, or downward.

[0039] Although some embodiments of the present disclosure have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, as well as in the invention described in the claims and the equivalent scope thereof.

Description of Reference Numerals

[0040] 1 Coil case 2 Substrate 3 Terminal 4 Solder 11 Coil housing portion 12 Upper surface 20 Spacing portion 30 Protrusion 40 Planar terminal hole portion 41, 51, 61 Through holes 42, 52, 62 Slits 43, 53, 63 Insertion portions 44, 54, 64 Support portions 50 Edge terminal hole portion

Claims

1. A coil case for holding a coil, comprising a terminal hole portion having a hole into which a terminal of the coil is inserted and soldered to a substrate, and a slit formed around the hole, and the slit is a gap in the coil case. Coil case.

2. The terminal hole portion has an insertion portion having a hole into which the terminal of the coil is inserted, and a support portion that supports the insertion portion from a direction orthogonal to the insertion direction of the terminal. The coil case according to claim 1.

3. The slit is formed around the insertion portion having a hole into which the terminal of the coil is inserted and a support portion that supports the insertion portion from a direction orthogonal to the insertion direction of the terminal. The coil case according to claim 1.

4. The support portion supports the insertion portion from a direction orthogonal to the longitudinal direction of the coil case. The coil case according to claim 2 or 3.

5. The support portion has a length in the same direction as the longitudinal direction of the coil case that is thinner than the insertion portion. The coil case according to claim 4.

6. The support portion has a length in a direction orthogonal to the longitudinal direction of the coil case that is longer than the diameter of the insertion portion. The coil case according to claim 4.

7. The support portion is curved. The coil case according to any one of claims 2 to 6.

8. The coil case has a first terminal hole portion disposed inside the upper surface of the coil case and a second terminal hole portion disposed outside the first terminal hole portion, and the slit of the second terminal hole portion is larger than the slit of the first terminal hole portion. The coil case according to any one of claims 1 to 7.

9. The hole has a first outer diameter and a second outer diameter, the first outer diameter is the outer diameter of the hole on the upper surface of the coil case, and the second outer diameter is narrower than the first outer diameter. The coil case according to claim 1.

10. The coil case has a protrusion disposed on the upper surface thereof, and the protrusion is disposed outside the terminal hole portion. The coil case according to claim 1.

11. A coil case for holding a coil, comprising a coil case having a terminal hole portion having a hole into which a terminal of the coil is inserted and soldered to a substrate, and a slit formed around the hole, and the coil held in the coil case. and the slit is a gap in the coil case. Switching power supply device.

12. The terminal hole portion has an insertion portion having the hole and a support portion that supports the insertion portion from a direction orthogonal to the insertion direction of the terminal. The switching power supply device according to claim 11.

13. The slit is formed around the terminal hole portion, which has an insertion portion having the hole and a support portion that supports the insertion portion from a direction orthogonal to the insertion direction of the terminal. The switching power supply device according to claim 11.

14. The support portion supports the insertion portion from a direction orthogonal to the longitudinal direction of the coil case. The switching power supply device according to claim 12 or 13.

15. The support portion has a length in the same direction as the longitudinal direction of the coil case that is thinner than the insertion portion. The switching power supply device according to claim 14.

16. The support portion has a length in a direction orthogonal to the longitudinal direction of the coil case that is longer than the diameter of the insertion portion. The switching power supply device according to claim 14.

17. The support portion is curved. The switching power supply device according to any one of claims 12 to 16.

18. The coil case has a first terminal hole portion disposed inside the upper surface of the coil case and a second terminal hole portion disposed outside the first terminal hole portion. The slit of the second terminal hole portion is larger than the slit of the first terminal hole portion. The switching power supply device according to any one of claims 11 to 17.

19. The hole has a first outer diameter and a second outer diameter. The first outer diameter is the outer diameter of the hole on the upper surface of the coil case. The second outer diameter is narrower than the first outer diameter. The switching power supply device according to claim 11.

20. It has a protrusion disposed on the upper surface of the coil case. The protrusion is disposed outside the terminal hole portion. The switching power supply device according to claim 11.

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