Coil device

Abstract

To provide a coil device which has excellent heat dissipation while allowing a reduction in a height and a size.SOLUTION: A coil device 10 has a bobbin 20. The bobbin 20 has: a first cylinder 21 around which a wire 40 is wound; a second cylinder 22 around which the wire 40 or another wire 40, different from the wire 40 mentioned above, is wound; and a coupling part 23 which couples the first cylinder 21 to the second cylinder 22. The bobbin has cores fitted thereto. The cores include: a first core 51 which has a first middle leg 512 inserted along an X-axis into the first cylinder 22; a second core 52 which has a second middle leg 522 inserted along the X-axis into the second cylinder 22 from an opposite side to the first middle leg 512; and an intermediate core 53 having at least two split pieces 53a and 53b which are inserted into the coupling part 23 from a direction substantially perpendicular to the X-axis and are assembled together to form a tabular shape.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a coil device used, for example, as a transformer. [Background technology]

[0002] As a conventional low-profile transformer, a coil device as shown in Patent Document 1 or Patent Document 2 below is known.

[0003] However, in conventional coil devices, it is common to arrange the cores in the axial direction on a base equipped with terminal electrodes, which results in insufficient heat dissipation and has proven difficult to accommodate recent trends such as larger currents and smaller size. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 6-196341 [Patent Document 2] Japanese Patent Application Publication No. 10-55925 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coil device that can be made low-profile and small-sized while having excellent heat dissipation properties. [Means for solving the problem]

[0006] In order to achieve the above object, a coil device according to the present invention comprises: a bobbin having a first cylinder around which a wire is wound, a second cylinder around which the wire or a wire different from the wire is wound, and a connecting portion connecting the first cylinder and the second cylinder; a first core having a first center leg that is inserted into the first cylinder along a first axis; a second core having a second center leg that is inserted into the second cylinder from the opposite side to the first center leg along the first axis; The intermediate core has at least two divided pieces that are inserted into the connecting portion in a direction substantially perpendicular to the first axis and combined to form a plate shape.

[0007] In the coil device of the present invention, the intermediate core has multiple split pieces, which are inserted into the connecting portion of the bobbin from a direction substantially perpendicular to the first axis and combined to form a plate-shaped core. Therefore, at the connecting portion of the bobbin, the members located between the multiple openings for inserting the multiple split pieces can easily form a reinforcing structure, improving the mechanical strength of the connecting portion of the bobbin. As a result, there is no need to provide a base or the like to increase the mechanical strength of the bobbin.

[0008] In the coil device of the present invention, since there is no need to provide a base or the like on the bobbin, the base of the bobbin does not exist in the middle of the heat dissipation path of the heat accumulated in the first core, the second core, or the intermediate core. As a result, it is possible to dissipate heat by contacting these cores with a member with excellent heat dissipation properties, improving heat dissipation. In addition, since there is no need to form a base or the like on the bobbin, it is possible to easily reduce the height and size of the coil device.

[0009] Preferably, the coil device further includes a case that houses the bobbin around which the wire is wound and to which the first core, the second core, and the intermediate core are attached. Preferably, the inside of the case is filled with, for example, a heat dissipating resin. With this configuration, heat generated in the wire, the first core, the second core, and the intermediate core is dissipated via the heat dissipating resin and the case, improving heat dissipation.

[0010] Preferably, the split pieces are inserted into the connecting portion from different directions and assembled inside the connecting portion. This configuration makes it easier to improve the strength of the connecting portion, and also makes it easier to increase the portions and areas of the intermediate core made of the split pieces that are exposed to the outside of the bobbin, thereby improving heat dissipation.

[0011] Preferably, inside the bobbin, a tip surface of the first center leg contacts one of the plate-shaped first surfaces of the intermediate core or faces the first center leg with a predetermined gap therebetween; Inside the bobbin, the tip surface of the second center leg contacts the other plate-shaped second surface of the intermediate core or faces the other plate-shaped second surface with a predetermined gap therebetween.

[0012] Even if the intermediate core is a combination of divided pieces, the above-mentioned configuration can be easily adopted, and the inductance of the coil device can be easily adjusted. In addition, the tip surface of the first center leg can be bonded to the multiple divided pieces by bonding the tip surface of the first center leg to the plate-like first surface of the intermediate core, and the joint strength between them is improved. Alternatively, the tip surface of the second center leg can be bonded to the multiple divided pieces by bonding the tip surface of the second center leg to the plate-like second surface of the intermediate core, and the joint strength between them is improved.

[0013] Preferably, the axis of the first cylinder and the axis of the second cylinder are arranged concentrically with the connecting portion therebetween, and the axis of the first cylinder is approximately parallel to the installation surface of the coil device. With this configuration, it is easy to reduce the height and size.

[0014] Preferably, the first core is a first base to which a base end of the first center leg is connected; and a pair of first outer legs connected to the first base so as to be positioned approximately parallel to both sides of the first center leg along a second axis approximately perpendicular to the first axis. That is, the first core may be a so-called E-shaped core.

[0015] Also, preferably, the second core is a second base to which the base end of the second middle leg is connected; and a pair of second outer legs connected to the second base so as to be located approximately parallel to each other on both sides of the second center leg along the second axis. That is, the second core may also be a so-called E-shaped core.

[0016] Preferably, the first base is A first base body including a region to which a base end of the first middle leg is connected; a pair of first support protrusions that protrude from both sides of the first base body along the second axis and along a third axis that is substantially perpendicular to both the first axis and the second axis, and that support a portion of the load of the coil device; A first support side recess may be formed between the pair of first support protrusions.

[0017] Also preferably, the second base is A second base body including a region to which the base end of the second middle leg is connected; a pair of second support protrusions protruding along the third axis from both sides of the second base body along the second axis and receiving a part of the load of the coil device; A second support side recess may be formed between the pair of second support protrusions.

[0018] By having the support protrusions of the core protrude so as to bear part of the load of the coil device, heat from the coil device is easily transferred through the support protrusions of the core to, for example, the bottom of the case close to a cooling mechanism (for example, a heat sink or a cooling heat transfer tube), further improving heat dissipation. Also, by forming a support side recess between the support protrusions, for example, a heat dissipating resin filled inside the case is easily able to enter the inside of the coil device from the support side recess, further improving heat dissipation. Furthermore, it is also possible to place a lower cover protruding from the flange of the bobbin in the first axial direction in the support side recess, which improves insulation and also makes it possible to hold the core.

[0019] Preferably, the first base is a pair of first opposite side protrusions protruding from both sides of the first base body along the second axis in a direction opposite to the first support protrusion along the third axis; A first opposite-side recess is formed between the pair of first opposite-side protrusions, A protruding height of the first support protrusion from the first base body along the third axis is smaller than a protruding height of the first opposite side protrusion from the first base body along the third axis.

[0020] Also preferably, the second base is a pair of second opposite side protrusions protruding from both sides of the second base body along the second axis in a direction opposite to the second support protrusion along the third axis; A second opposite-side recess is formed between the pair of second opposite-side protrusions, A protruding height of the second support protrusion from the second base body along the third axis is smaller than a protruding height of the second opposite side protrusion from the second base body along the third axis.

[0021] By reducing the protruding height of the support convex portion, the outer periphery of the wire wound around the first and / or second tube is brought closer to the bottom of the case, which is close to the cooling mechanism, for example, and the heat from the wire is easily dissipated directly, further improving heat dissipation. In addition, by increasing the protruding height of the opposite-side convex portion, the opposite-side concave portion formed between the opposite-side convex portions can also be made deeper, making it possible to use that space for routing the wire, etc. Furthermore, it is also possible to place a cover that protrudes from the flange of the bobbin in the first axial direction in the opposite-side concave portion, which improves insulation and also makes it possible to hold the core.

[0022] Preferably, a first flange is provided integrally with the bobbin at one end along the first axial direction to ensure insulation between the inner surface of the first base and the outer circumferential surface of the first tube. Also preferably, a second flange is provided integrally with the bobbin at the other end along the first axial direction to ensure insulation between the inner surface of the second base and the outer circumferential surface of the second tube. Also preferably, a first intermediate flange is provided integrally with the bobbin at the boundary between the connecting portion and the first tube to ensure insulation between the inner side of the connecting portion and the outer circumferential surface of the first tube. More preferably, a second intermediate flange is provided integrally with the bobbin at the boundary between the connecting portion and the second tube to ensure insulation between the inner side of the connecting portion and the outer circumferential surface of the second tube.

[0023] The first intermediate flange and / or the second intermediate flange may be provided with a wire groove through which the wire can pass. Similarly, the first flange and / or the second flange may be provided with a wire groove through which the wire can pass. With this configuration, the degree of freedom of wiring the wire between the first tube and the second tube is improved, and the degree of freedom of routing the wire is improved. Therefore, the coil device of the present invention can be used as a single transformer or as a coil device in which multiple transformers are integrated, making it easy to freely design transformers or other circuits.

[0024] Preferably, the first intermediate flange and the second intermediate flange may be provided with a terminal block connection portion that connects these flanges so as to span them. The terminal block provided with the terminal may be molded integrally with the bobbin, but is preferably molded separately from the bobbin and attached to the bobbin. The first intermediate flange and the second intermediate flange are located in the middle along the first axis of the coil device, and can be preferably used as the point where the terminal block is connected.

[0025] The terminal block connection portion may be provided on the first and second flanges as well as the first and second flanges. In this case, it is easy to attach a long terminal block along the first axis to the bobbin, spanning the first flange, the first intermediate flange, the second intermediate flange, and the second flange. This makes it possible to arrange many terminals at predetermined intervals on the long terminal block.

[0026] The terminal block long along the first axis may be divided into a plurality of terminal blocks. In applications requiring a small number of terminals, the terminal block connection portion may be provided on one or more of the first flange, the intermediate first flange, the intermediate second flange, and the second flange. It is preferable that the terminal block connection portion is provided on the opposite side along the third axis from the installation surface of the coil device (for example, the bottom surface of the case).

[0027] The terminal block connection portion may extend from each flange in a direction parallel to the second axis, in the third axis direction, or in a direction intermediate therebetween. In any case, by providing the terminal block connection portion on the opposite side along the third axis from the installation surface of the coil device (for example, the bottom surface of the case), it is possible to make the terminal block protrude outside the case, and it is possible to satisfy both the heat dissipation properties and the compactness of the coil device.

[0028] The first cylinder located near the intermediate first flange may be provided with an auxiliary first flange. The second cylinder located near the intermediate second flange may be provided with an auxiliary second flange. These auxiliary flanges are also preferably provided with a wire groove through which a wire can pass. By providing the auxiliary flange, it becomes easier to wind the wire wound around the first cylinder around a part of the second cylinder, or to wind the wire wound around the second cylinder around a part of the first cylinder, and it becomes possible to form auxiliary circuits necessary for circuits such as a transformer in the coil device, improving the freedom of design.

[0029] Preferably, the shape of the intermediate core as viewed from the direction along the first axis is substantially the same as the shape of the first core or the second core as viewed from the direction along the first axis. By configuring in this way, it becomes possible to form a support convex portion or an inverted convex portion similar to the first flange of the first core or the second flange of the second core in the intermediate core, and the same action and effect as the first core or the second core as described above can be expected. Note that the support convex portion or the inverted convex portion similar to the first flange of the first core or the second flange of the second core may also be provided in the first outer leg or the second outer leg. [Brief description of the drawings]

[0030] [Figure 1] FIG. 1 is a schematic perspective view of a coil device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a perspective view of the main part of the coil device shown in FIG. 1 excluding the case. [Diagram 3] FIG. 3 is a cross-sectional perspective view taken along line III-III shown in FIG. [Figure 4]FIG. 4 is an exploded perspective view of the coil device shown in FIG. [Diagram 5] FIG. 5 is a perspective view of the bobbin shown in FIG. 4, showing a state before the wire is wound around the bobbin. [Figure 6] FIG. 6 is a perspective view of the bobbin shown in FIG. 5, showing a state after the wire has been wound around the bobbin. [Figure 7] FIG. 7 is a perspective view of the bobbin after the terminal block is attached, showing an example of wiring of the wires shown in FIG. [Figure 8] FIG. 8 is a circuit diagram showing an example of a circuit of the coil device shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Hereinafter, the present invention will be described based on the embodiments shown in the drawings.

[0032] 1, a coil device 10 according to an embodiment of the present invention includes a bobbin 20, a terminal block 30, one or more wires 40, a core 50, and a case 100. In the drawings of this embodiment, the X-axis, Y-axis, and Z-axis are mutually perpendicular, and the X-axis is parallel to the winding axis of the wire 40.

[0033] The inside of the case 100 is filled with a heat dissipating resin 60. The heat dissipating resin 60 is filled inside the case 100 so that most of the lower parts of the bobbin 20 and the core 50 along the Z axis are buried inside the resin 60, and the wire 40 wound around the bobbin 20 is completely buried inside the resin, except for the lead part 40a. The terminal block 30 attached to the upper part of the bobbin 20 in the Z axis direction is located outside the case 100, and in this embodiment, is located above the upper opening of the case 100. However, the terminal block 30 may be located below the upper opening of the case 100 as long as it is located outside the part filled with the resin 60 inside the case 100, or may be located outside the case 100 along the Y axis or X axis.

[0034] The resin 60 may be, for example, a potting resin with excellent thermal conductivity. The potting resin may be a silicone resin, a urethane resin, an epoxy resin, or the like that remains soft even after injection, and the potting resin preferably has a longitudinal elastic modulus of 0.1 to 100 MPa. The case 100 is made of a metal with excellent cooling properties, such as aluminum.

[0035] As shown in FIG. 2, the core 50 is composed of a first core 51, a middle core 53, and a second core 52, which are arranged along the X-axis. 5 The cores 51 to 3 may be made of the same material or different materials, but are preferably made of the same magnetic material. 5 The component 3 is made of a ferrite composition, a metal magnetic composition, a composite composition of these with resin, or the like, and is manufactured by methods such as compression molding followed by sintering, injection molding followed by sintering, or general powder compaction.

[0036] As shown in FIG. 4, the first core 51 has a first base 511 to which the base end of the first middle leg 512 is connected, and a pair of first outer legs 513 each connected to the first base 511 so as to be positioned approximately parallel to either side of the first middle leg 512 along the Y axis.

[0037] The first base 511 includes a first base body 511a including a region to which the base end of the first middle leg 512 is connected, and a first base body 511b extending from both sides of the first base body 511a along the Y axis. Z The coil device 10 has a pair of first support protrusions 514 that protrude downward along the axis and support part of the load of the coil device 10. A first support side recess 515 is formed between the pair of first support protrusions 514.

[0038] The first base 511 further has a pair of first opposite-side convex portions 516 that protrude in the opposite direction along the Z axis from the first support convex portion 514 from both sides of the first base main body 511a along the Y axis, and a first opposite-side concave portion 517 is formed between the pair of first opposite-side convex portions 516. As shown in Fig. 3, the protruding height Z1 of the first support convex portion 514 along the Z axis from the first base main body 511a is smaller than the protruding height Z2 of the first opposite-side convex portion 516 along the Z axis from the first base main body 511a.

[0039] As shown in Fig. 4, in this embodiment, the first outer leg 513 has a first inner recess 512a that matches the outer circumferential surface shape of the first middle leg 512 so as to surround the first middle leg 512 from both sides in the Y-axis direction at a predetermined distance. The first inner recess 512a is in contact with or disposed at a predetermined distance from the outer circumferential edges located on both sides along the Y-axis of the first flange 213, the intermediate first flange 214, and the auxiliary first flange 215 of the bobbin 20 shown in Fig. 5. The outer circumferential surface shape of the first outer leg 513 is the same as the outer circumferential surface shape of the first base 511 including the protrusions 514 and 516.

[0040] The second core 52 is connected to the second base 5 2 1 and the second middle leg 5 along the Y axis 2 A pair of the second bases 521 are connected to the second base 521 so as to be located approximately parallel to each other on both sides of the second base 521. Second outer leg 523 And, it has.

[0041] The second base 521 is a first base including a region to which the base end of the second middle leg 522 is connected. 2 From both sides of the base body 521a and the second base body 521a along the Y axis, Z and a pair of second support protrusions 524 (see FIG. 3) that protrude downward along the axis and support part of the load of the coil device 10. A second support side recess 525 is formed between the pair of second support protrusions 524.

[0042] The second base 521 further has a pair of second opposite side protrusions 526 that protrude from both sides of the second base main body 521a along the Y axis in the opposite direction to the second support protrusion along the Z axis, and a second opposite side recess 527 is formed between the pair of second opposite side protrusions 526. 2 The protruding height of the second support protrusion 524 from the second base main body 521a along the Z axis is smaller than the protruding height of the opposite-side protrusion 526 along the Z axis, which is the same as the relationship between the protruding heights Z1 and Z2 shown in FIG. 3.

[0043] In this embodiment, the second outer leg 523 has a second inner recess 522a that matches the outer circumferential surface shape of the second middle leg 522 so as to surround the second middle leg 522 from both sides in the Y-axis direction at a predetermined distance. The second inner recess 522a is in contact with or disposed at a predetermined distance from the outer circumferential edges located on both sides along the Y-axis of the second flange 223, the intermediate second flange 224, and the auxiliary second flange 225 of the bobbin 20 shown in FIG. 5. The outer circumferential surface shape of the second outer leg 523 is the same as the outer circumferential surface shape of the second base 521 including the protrusions 524 and 526.

[0044] In this embodiment, the second core 52 preferably has the same configuration as the first core 51, but is not necessarily the same. For example, the length in the X-axis direction of the second center leg 522 and the second outer leg 523 is 1 The length in the X-axis direction may be different from that of outer leg 513. In this embodiment, the cross-sectional shape of center leg 512 and 522 is a substantially ellipse that is long along the Y-axis, but it may be a circle, a polygon, or another shape.

[0045] As shown in FIG. 4, in this embodiment, the intermediate core 53 is a plate-shaped core having at least two split pieces 53a, 53b, which are inserted into the connecting portion of the bobbin 20 from a direction approximately perpendicular to the X-axis (for example, along the Y-axis, but may be in other perpendicular directions) and assembled to form a plate-like shape.

[0046] In this embodiment, the two divided pieces 53a, 53b come into contact with each other at their mating surfaces 53c, 53c to form one intermediate core 53. An adhesive may be applied to any of the mating surfaces 53c, 53c. In this embodiment, the mating surfaces 53c, 53c are planes parallel to a plane including the X-axis and the Z-axis, but the mating surfaces 53c, 53c are not limited thereto, and may be any surfaces that can be combined to form the plate-shaped intermediate core 53. For example, the mating surfaces 53c, 53c may be inclined at an angle other than perpendicular to the Y-axis. In addition, the mating surfaces 53c, 53c are not necessarily a combination of planes, and may be a combination of a convex surface and a concave surface.

[0047] In this embodiment, the shape of the intermediate core 53 formed by combining the divided pieces 53a and 53b as viewed from the X axis is preferably the same as the shape of the first base 511 and / or the second base 521 as viewed from the X axis. side It has a recess 535 , a middle reverse side protrusion 536 , and a middle reverse side recess 537 .

[0048] In this embodiment, the thickness of the intermediate core 53 along the X-axis is not particularly limited, but is thicker than the thickness of the first base 511 or the second base 521 in the X-axis direction, and is preferably about 1.5 to 2.5 times thicker. This is because two magnetic paths are formed in the intermediate core 53, mainly through the first core 51 and the second core 52, respectively.

[0049] 3, the bobbin 20 has a first tube 21 around which the wire 40 is wound, a second tube 22 around which the same wire 40 or a different wire 40 is wound, and a connecting portion 23 connecting the first tube 21 and the second tube 22. The first tube 21, the connecting portion 23, and the second tube 22 are concentrically arranged along an axis (central axis) X1 parallel to the X-axis, and the axis X1 of the first tube 21 is approximately parallel to the installation surface of the coil device 10 (a surface approximately perpendicular to the Z-axis on the lower side along the Z-axis). This configuration facilitates a reduction in height and size.

[0050] 5, the first cylinder 21 of the bobbin 20 has a first cylinder body 212 in which a through hole 211 extending in the X-axis direction is formed. On the outer circumferential surface of the first cylinder body 212, as shown in FIG. 3, a single or multiple wires 40 are wound in one layer or two or more layers.

[0051] At one end of the bobbin 20 along the X-axis direction, a first flange 213 is integrally provided on the bobbin 20 to ensure insulation between the inner surface of the first base 511 of the first core 51 shown in Fig. 4 and the outer peripheral surface of the first cylinder 21. At the other end of the bobbin 20 along the X-axis direction, a first flange 213 is integrally provided on the bobbin 20 to ensure insulation between the inner surface of the second base 521 of the second core 52 shown in Fig. 4 and the outer peripheral surface of the second cylinder 21 shown in Fig. 22 A second flange 223 for ensuring insulation from the outer circumferential surface of the bobbin 20 is provided integrally with the bobbin 20.

[0052] As shown in FIG. 5, at the boundary between the connecting portion 23 and the first cylinder 21, 21 The bobbin 20 is provided integrally with a first intermediate flange 214 that ensures insulation from the outer peripheral surface of the second cylinder. 22 At the boundary between the inside of the connecting portion 23 and the second cylinder 22 A second intermediate flange 224 is integrally formed on the bobbin 20 to ensure insulation from the outer circumferential surface of the bobbin.

[0053] In addition, the first barrel located near the intermediate first flange 214 Main unit 212 is provided with an auxiliary first flange 215, as well as a second barrel located near the intermediate second flange 224. Main unit The first cylinder 222 is provided with an auxiliary second flange 225. These flanges 213, 223, 214, 215, 224, and 225 are approximately parallel to each other and are arranged on the first cylinder 222 so as to protrude in the radial direction from the central axis X1 of the bobbin 20 (see FIG. 3). Main unit 212 or 2nd tube Main unit 222.

[0054] In this embodiment, a plurality of wire grooves 214a, 224a capable of passing the wire 40 shown in Fig. 3 are provided above the first intermediate flange 214 and / or the second intermediate flange 224 along the Z axis. Also, in this embodiment, a single wide wire groove 215a, 225a capable of passing the wire 40 shown in Fig. 3 is provided above the first auxiliary flange 215 and / or the second auxiliary flange 225 along the Z axis. Furthermore, in this embodiment, a plurality of wire grooves 213a, 223a capable of passing the wire 40 shown in Fig. 3 are provided above the first flange 213 and / or the second flange 223 along the Z axis.

[0055] These wire grooves 213a, 223a, 214a, 224a, 215a, and 225a are formed in parallel so as to open upward along the Z axis, but may be formed so as to open outward in the radial direction. In this embodiment, the groove depth of the wire grooves 215a and 225a is formed deeper than the groove depth of the wire grooves 213a, 223a, 214a, and 224a, and the bottoms of the grooves 215a and 225a are formed so as to be in contact with the first cylinder. Main unit 212 or 2nd tube Main unit The grooves 215a and 225a may coincide with the outer circumferential surface of the tube 212 or 222. This is because the grooves 215a and 225a are formed on the outer circumferential surface of the same tube 212 or 222, and therefore there is no need to insulate them.

[0056] An intermediate terminal block connection portion 238 that connects the first intermediate flange 214 and the second intermediate flange 224 so as to span across these flanges 214, 224 is provided at the upper portions along the Z axis of the first intermediate flange 214 and the second intermediate flange 224. The intermediate terminal block connection portion 238 is formed so as to protrude outward along the Y axis from the upper portions along the Z axis of the first intermediate flange 214 and the second intermediate flange 224, and in this embodiment, has a plane parallel to the Y axis and the X axis.

[0057] Also, a first terminal block connection portion 218 is provided on an upper portion of the first flange 213 along the Z axis so as to be substantially parallel to the intermediate terminal block connection portion 238. The first terminal block connection portion 218 is formed so as to protrude outward along the Y axis from an upper portion of the first flange 213 along the Z axis. Similarly, a second terminal block connection portion 228 is provided on an upper portion of the second flange 223 along the Z axis so as to be substantially parallel to the intermediate terminal block connection portion 238. The second terminal block connection portion 228 is formed so as to protrude outward along the Y axis from an upper portion of the second flange 223 along the Z axis.

[0058] These terminal block connecting portions 218, 228, 238 fit into mounting recesses of the terminal block 30, and the terminal block 30 is attached and fixed to the bobbin 20. In this embodiment, as shown in Fig. 6, the terminal block 30 has split terminal blocks 30a, 30b that can be separated into two or more, and a connector 30c that engages with a fitting portion provided below the split terminal blocks 30a, 30b in the Z-axis direction to integrate the split terminal blocks 30a, 30b.

[0059] Each of the split terminal blocks 30a, 30b is provided with one or more terminals 32. As shown in Fig. 7, each of the terminals 32 has a lead connection portion 321 to which lead portions 40a of the wires 40 wound around the bobbin 20 are attached and connected, and an external connection portion 322 connected to the lead connection portion 321 inside the split terminal block 30a or 30b. In this embodiment, the external connection portions 322 protrude from the terminal block 30 upward along the Z axis at predetermined intervals along the X axis, and the lead connection portions 321 protrude from the terminal block 30 outward along the Y axis at predetermined intervals along the X axis.

[0060] As shown in Fig. 5, below the first flange 213 of the bobbin 20 along the Z axis, a lower cover 216 is formed which protrudes outward from the first flange 213 along the X axis. The shape of the lower cover 216 matches the shape of the inner surface of the first support side recess 515 formed below the Z axis of the first base 511 of the first core 51 shown in Fig. 4, and covers the recess 515 from below. Similarly, below the second flange 223 of the bobbin 20 along the Z axis, a lower cover 226 (see Fig. 3) which protrudes outward from the second flange 223 along the X axis is integrally formed.

[0061] As shown in Fig. 5, an upper cover 217 is formed above the first flange 213 of the bobbin 20 along the Z axis, protruding outward from the first flange 213 along the X axis. The shape of the upper cover 217 matches the inner shape of the first opposite recess 517 formed above the Z axis of the first base 511 of the first core 51 shown in Fig. 4, and covers the recess 517 from above. Similarly, an upper cover 227 is integrally formed above the second flange 223 of the bobbin 20 along the Z axis, protruding outward from the second flange 223 along the X axis. The outer sides of the upper covers 217, 227 along the Y axis and the upper sides along the Z axis are integrally connected to the terminal block connection parts 218, 228, respectively.

[0062] A lower connecting cover 236 and an upper connecting cover 237 are arranged on the connecting portion 23 of the bobbin 20, which respectively connect the intermediate first flange 214 (first tube 21) and the intermediate second flange 224 (second tube 22) integrally at the upper or lower side along the Z axis.

[0063] The shape of the lower connecting cover 236 seen from the direction along the X-axis is approximately the same as that of the lower cover 216, and the top surfaces of these covers 216, 236 are flush with the bottom surfaces of the through-holes 211, 221 (see FIG. 3). The shape of the upper connecting cover 237 seen from the direction along the X-axis is approximately the same as that of the upper cover 217, and the inner surfaces of these covers 217, 237 are located higher along the Z-axis than the top surfaces of the through-holes 211, 221 (see FIG. 3).

[0064] 5, in the connecting portion 23, a pair of openings 231 that connect the inside and outside along the Y-axis direction is formed between the upper connecting cover and the lower connecting cover. In each opening 231, an intermediate base 531 on which mating surfaces 53c, 53c of the divided pieces 53a, 53b shown in FIG. 4 are formed is inserted, and inside the connecting portion 23, the mating surfaces 53c of the divided pieces 53a, 53b are butted against each other to form the intermediate core 53.

[0065] As shown in Fig. 4, the intermediate core 53 is divided into divided pieces 53a and 53b at a dividing surface (mating surface 53c), and as shown in Fig. 3, a tip surface of the first center leg 512 is in contact with and bonded to a first surface 53d on one side along the X-axis where the mating surface 53c appears as a straight line. Also, a tip surface of the second center leg 522 is in contact with and bonded to a second surface 53e on the other side along the X-axis where the mating surface 53c appears as a straight line. The adhesive for bonding these together can also be used as the adhesive for bonding the mating surfaces 53c together.

[0066] In addition, a gap of a predetermined size may be formed between the first surface 53d and the tip surface of the first center leg 512, or between the second surface 53e and the tip surface of the second center leg 522, in order to adjust inductance, etc.

[0067] In this embodiment, the bobbin 20 shown in Fig. 5 is molded by, for example, injection molding, and the material is not particularly limited, but may be, for example, PBT, PET, LCP, PA, or phenol resin from the viewpoint of heat resistance. The split terminal blocks 30a and 30b molded separately from the bobbin 20 may be made of the same resin as the bobbin 20 or may be made of a different resin, and it is preferable that the terminal 32 is insert molded. Also, the connector 30c shown in Fig. 6 may be made of the same material as the split terminal blocks 30a and 30b or may be made of a different material.

[0068] The material of the wire 40 is not particularly limited, and may be, for example, a conductive wire with an insulating coating, such as copper, a copper alloy, iron, an iron alloy, or a CP wire. The insulating material constituting the insulating coating is not particularly limited, and may be, for example, urethane, polyamideimide, or ETFE.

[0069] In this embodiment, a single or multiple wires 40 are wound around the outer circumferential surfaces of the first tube 21 and the second tube 22, as shown in FIG. 3. A part of the wire 40 wound around the outer circumferential surface of the first tube 21 may be wound around the outer circumferential surface of the second tube 22 located between the intermediate second flange 224 and the auxiliary second flange 225. Conversely, a part of the wire 40 wound around the outer circumferential surface of the second tube 22 may be wound around the outer circumferential surface of the first tube 21 located between the intermediate first flange 214 and the auxiliary first flange 215. By winding the wire 40 in this manner, a coil device 10 in which multiple transformer circuits are integrated can be realized, as shown in FIG. 8.

[0070] As shown in FIG. 4, in the coil device 10 of this embodiment, the intermediate core 53 is made up of a plurality of divided pieces 53a, 5 3b, which are inserted into the connecting portion 23 of the bobbin 20 from a direction substantially perpendicular to the X-axis (for example, a direction along the Y-axis) and combined to form a plate-shaped core. Therefore, in the connecting portion 23 of the bobbin 20, the connecting covers 236, 237 located between the multiple openings 231, 231 for inserting the multiple divided pieces 53a, 53b can easily form a reinforcing structure, improving the mechanical strength of the connecting portion 23 of the bobbin 20. As a result, it is not necessary to provide a base or the like for increasing the mechanical strength of the bobbin 20.

[0071] In the coil device 10 of this embodiment, since it is not necessary to provide a base or the like on the bobbin 20, the base of the bobbin 20 does not exist in the middle of the heat dissipation path (downward along the Z-axis) of heat accumulated in the first core 51, the second core 52, or the intermediate core 53, as shown in Fig. 3. As a result, it becomes possible to dissipate heat by directly contacting the lower ends along the Z-axis of the cores 51, 52, and 53 shown in Fig. 2 with the inner bottom wall of the case 100, which has excellent heat dissipation properties, shown in Fig. 1, thereby improving heat dissipation. In addition, since it is not necessary to form a base or the like on the bobbin 20, it is possible to easily reduce the height and size of the coil device 10.

[0072] 1, the inside of the case 100 is filled with, for example, heat dissipating resin 60. With this configuration, heat generated in the wire 40, the first core 51, the second core 52, and the intermediate core 53 is dissipated via the heat dissipating resin 60 and the case 100, improving heat dissipation.

[0073] 4, the split pieces 53a and 53b are inserted into the connecting portion 23 from different directions and combined inside the connecting portion 23. This configuration makes it easier to improve the strength of the connecting portion 23, and also makes it easier to increase the portion and area of ​​the intermediate core 53 made up of the split pieces 53a and 53b that is exposed to the outside of the bobbin 20, thereby improving heat dissipation.

[0074] Furthermore, as shown in FIG. 3, inside the bobbin 20, the tip surface of the first center leg 512 contacts (or has a predetermined gap with) one plate-shaped first surface 53d of the intermediate core 53, and the other plate-shaped second surface 53 e The tip surface of the second middle leg 522 comes into contact with the intermediate core 53 (or there is a predetermined gap between the intermediate core 53 and the split pieces 53a and 53b). Therefore, even if the intermediate core 53 is a combination of the split pieces 53a and 53b, the above-mentioned configuration can be easily adopted, and the inductance of the coil device 10 can be easily adjusted.

[0075] Also, by bonding the tip surface of the first center leg 512 to the plate-shaped first surface 53d of the intermediate core 53, the tip surface of the first center leg 512 can be bonded to the multiple divided pieces 53a, 53b, improving the bonding strength thereof. Alternatively, by bonding the tip surface of the second center leg 522 to the plate-shaped second surface 53e of the intermediate core 53, the tip surface of the second center leg 522 can be bonded to the multiple divided pieces 53a, 53b, improving the bonding strength thereof.

[0076] In this embodiment, the axial core of the first tube 21 and the axial core of the second tube 22 are arranged concentrically with the connecting portion 23 in between, and the axial core of the first tube 21 is approximately parallel to the installation surface of the coil device 10. This configuration facilitates low height and miniaturization. The installation surface of the coil device 10 is the lower surface along the Z axis of the case 100 when the case 100 is present, and is the lower surface along the Z axis of the cores 51, 52, and 53 when the case 100 is not present.

[0077] 4, in this embodiment, the support protrusions 514, 524, and 534 of the cores 51 to 53 protrude in the Z-axis direction so as to receive part of the load of the coil device 10, so that heat from the coil device 10 can be transferred to the case 100 through the support protrusions 514, 524, and 534 of the cores. A cooling mechanism (such as a heat sink or a heat transfer tube for cooling) is disposed below the case 100, for example, to further improve heat dissipation.

[0078] Moreover, by forming the support side recesses 515, 525, 535 between the support protrusions 514, 524, 534, for example, the heat dissipation resin 60 filled inside the case 100 can easily enter the inside of the coil device 10 from the support side recesses 515, 525, 535, further improving heat dissipation. Furthermore, it is also possible to arrange the lower covers 216, 226, 236 protruding in the X-axis direction from the flanges 213, 223, 214, 224 of the bobbin 20 in the support side recesses 515, 525, 535, improving insulation and enabling the cores 51, 52, 53 to be held.

[0079] In this embodiment, by reducing the protruding height of the support protrusions 514, 524, and 534, as shown in FIG. Main unit 212 and 2nd tube Main unit The outer peripheral position of wire 40 wound around 222 is closer to the bottom of case 100 shown in FIG. 1, which is close to the cooling mechanism, so that heat from wire 40 can be easily dissipated directly, further improving heat dissipation.

[0080] 4, it is possible to form the depth of the opposite-side recesses 517, 527, 537 deeper, and the space in that portion can be used as a space for routing the wire 40. Furthermore, it is also possible to place the covers 217, 227, 237 protruding in the X-axis direction from the flange of the bobbin 20 shown in FIG. 5 in the opposite-side recesses 517, 527, 537, which improves insulation and also makes it possible to hold the cores 51, 52, 53.

[0081] Further, in this embodiment, the intermediate first flange 214 and / or the intermediate second flange 215 may be 2 The flange 224 may be provided with wire grooves 214a, 224a through which the wire 40 can pass. Similarly, the first flange 213 and / or the second flange 223 may be provided with wire grooves 213a, 223a through which the wire 40 can pass. Furthermore, the auxiliary first flange 215 and / or the auxiliary second flange 225 may also be provided with wire grooves 215a, 225a through which the wire 40 can pass.

[0082] This configuration improves the degree of freedom in wiring the wire 40 between the first tube 21 and the second tube 22, and improves the degree of freedom in routing the wire 40. Therefore, the coil device 10 of the present embodiment can be used as a single transformer, or as a coil device in which multiple transformers are integrated, facilitating free design of transformers or other circuits.

[0083] Furthermore, in this embodiment, the first intermediate flange 214 and the second intermediate flange 224 are provided with a terminal block connection portion 238 that connects these flanges so as to span them. The terminal block 30 equipped with the terminal 32 may be molded integrally with the bobbin 20, but is preferably molded separately from the bobbin 20 and attached to the bobbin 20. The first intermediate flange 214 and the second intermediate flange 224 are located in the middle along the X-axis of the coil device 10, and can be preferably used as a point to which the terminal block 30 is connected.

[0084] Furthermore, the terminal block connection parts 218, 228 may be provided on the first flange 213 and the second flange 223 as well as the intermediate first flange 214 and the intermediate second flange 224. In that case, it becomes easy to attach the long terminal block 30 along the X-axis to the bobbin 20 across the first flange 213, the intermediate first flange 214, the intermediate second flange 224, and the second flange 223. Therefore, it becomes possible to arrange many terminals 32 on the long terminal block 30 at predetermined intervals along the X-axis.

[0085] In this embodiment, the terminal block 30, which is long along the X-axis, is composed of a plurality of divided terminal blocks 30a, 30b. However, in an application in which a small number of terminals 32 is required, the terminal block connection portion 218, 228, or 238 may be provided on one or more of the first flange 213, the intermediate first flange 214, the intermediate second flange 224, and the second flange 223. In addition, it is preferable that the terminal block connection portion 218, 228, or 238 is provided on the opposite side along the Z-axis from the installation surface of the coil device 10 (for example, the bottom surface of the case 100).

[0086] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

[0087] 6 may extend from each of the flanges 213, 223, 214, 224 in the Z-axis direction or in a direction intermediate between the Y-axis and the Z-axis, other than in a direction parallel to the Y-axis. In any case, by providing the terminal block connecting parts 218, 228, 238 on the opposite side along the Z-axis from the installation surface of the coil device 10 (for example, the bottom surface of the case 100), it is possible to protrude the terminal block 30 to the outside of the case 100, and it is possible to satisfy both the heat dissipation property and the miniaturization of the coil device 10. [Explanation of symbols]

[0088] 10... Coil device 20… Bobbin 21… 1st tube 211...Through hole 212... 1st cylinder body 213... First tsuba 213a… Wire groove 214... Middle 1st tsuba 214a… Wire groove 215... Auxiliary 1st tsuba 215a… Wire groove 216… Lower cover 217…Upper cover 218… First terminal block connection 22…Second tube 221...Through hole 222…Second cylinder body 223... Second tsuba 223a… Wire groove 224... Middle 2nd tsuba 224a… Wire groove 225... Auxiliary 2nd tsuba 225a… Wire groove 226… Lower cover 227…Upper cover 228… Terminal block 2 connection 23…Connection part 231…Aperture 236… Lower connecting cover 237…Upper connecting cover 238... Intermediate terminal block connection 30…Terminal block 30a,30b…Split terminal block 30c... Connector 32... Terminal 321… Lead connection part 322… External connection part 40… Wire 50… Core 51… First Core 511... First Base 511a... First base body 512… 1st middle leg 513... First outside leg 514… First support protrusion 515... 1st support side recess 516… First reverse convex part 517… First opposite recess 52… 2nd core 521... 2nd base 5 21 a... 2nd base body 522…second middle leg 523... 2nd outside leg 524… Second support protrusion 525... 2nd support side recess 526… Second opposite convex part 527… Second opposite recess 53... Intermediate core 53a… Split piece 53b… Split piece 53c…Mating surface 53d… 1st surface 53e... 2nd surface 531... Intermediate base 534... Intermediate support protrusion 535… Intermediate support side recess 536… Middle reverse convex part 537… Middle reverse recess 60… Heat dissipating resin 100… Case

Claims

1. a bobbin having a first cylinder around which a wire is wound, a second cylinder around which the wire or a wire different from the wire is wound, and a connecting portion connecting the first cylinder and the second cylinder; a first core having a first center leg that is inserted into the first cylinder along a first axis; a second core having a second center leg inserted into the second cylinder from the opposite side to the first center leg along the first axis; an intermediate core having at least two divided pieces, the intermediate core being inserted into the connecting portion from a second axial direction substantially perpendicular to the first axial direction and assembled to form a plate shape; A pair of openings are formed in the connecting portion so that the split pieces can enter therethrough, The mating surfaces of the divided pieces that enter through the openings are combined inside the connecting portion, An outer leg portion of the first core contacts the divided piece or faces the divided piece with a predetermined gap therebetween, and an outer leg portion of the second core contacts the divided piece or faces the divided piece with a predetermined gap therebetween, Within the bobbin, a center leg portion of the first core contacts a first surface of the split piece or faces the first surface of the split piece with a predetermined gap therebetween, and a center leg portion of the second core contacts a second surface of the split piece or faces the second surface of the split piece with a predetermined gap therebetween; the first cylinder, the second cylinder, and the connecting portion have an integral structure that is not divided; The connecting portion constituting the bobbin has an upper connecting cover and a lower connecting cover that sandwich the opening from above and below, The upper connecting cover and the lower connecting cover connect the first cylinder and the second cylinder along the first axial direction, The lower connecting cover is continuous without seams across at least two of the divided pieces in the second axial direction. Coil device.

2. The coil device according to claim 1 , further comprising a case that houses the bobbin around which the wire is wound and to which the first core, the second core and the intermediate core are attached.

3. The coil device according to claim 2 , wherein the inside of the case is filled with a heat dissipating resin.

4. an axial core of the first cylinder and an axial core of the second cylinder are arranged concentrically with the connecting portion therebetween, 4. The coil device according to claim 1, wherein the axis of the first cylinder is approximately parallel to a surface on which the coil device is installed.

5. The first core is a first base to which a base end of the first middle leg is connected; a pair of first outer legs each connected to the first base so as to be positioned approximately parallel to both sides of the first middle leg along a second axis that is approximately perpendicular to the first axis; The second core is a second base to which a base end of the second middle leg is connected; a pair of second outer legs each connected to the second base so as to be positioned approximately parallel to both sides of the second middle leg along the second axis; The coil device according to any one of claims 1 to 4.

6. The first base is a first base body including a region to which a base end of the first middle leg is connected; a pair of first support protrusions protruding from both sides of the first base body along the second axis and along a third axis that is substantially perpendicular to both the first axis and the second axis, and that support a portion of the load of the coil device; A first support-side recess is formed between the pair of first support protrusions, The second base is A second base body including a region to which a base end of the second middle leg is connected; a pair of second support protrusions protruding along the third axis from both sides of the second base body along the second axis and configured to support a portion of the load of the coil device; A second support side recess is formed between the pair of second support protrusions. The coil device according to claim 5 .

7. The first base is a pair of first opposite side protrusions protruding from both sides of the first base body along the second axis in a direction opposite to the first support protrusion along the third axis; A first opposite-side recess is formed between the pair of first opposite-side protrusions, a protruding height of the first support protrusion from the first base body along the third axis is smaller than a protruding height of the first opposite side protrusion from the first base body along the third axis, The second base is a pair of second opposite side protrusions protruding from both sides of the second base body along the second axis in a direction opposite to the second support protrusion along the third axis; A second opposite-side recess is formed between the pair of second opposite-side protrusions, A protruding height of the second support protrusion from the second base body along the third axis is smaller than a protruding height of the second opposite side protrusion from the second base body along the third axis. The coil device according to claim 6.

8. a first flange for ensuring insulation between an inner surface of the first base and an outer peripheral surface of the first cylinder is integrally formed on one end of the bobbin along the first axial direction, a second flange for ensuring insulation between an inner surface of the second base and an outer peripheral surface of the second cylinder is integrally formed on the bobbin at the other end along the first axial direction, a first intermediate flange is integrally formed on the bobbin at a boundary between the connecting portion and the first cylinder to ensure insulation between an inside of the connecting portion and an outer peripheral surface of the first cylinder; A coil device as described in any one of claims 5 to 7, wherein an intermediate second flange is integrally provided on the bobbin at the boundary between the connecting portion and the second tube to ensure insulation between the inside of the connecting portion and the outer peripheral surface of the second tube.

9. 9. The coil device according to claim 8, wherein the first intermediate flange and / or the second intermediate flange is provided with a wire groove through which the wire can pass.

10. 10. The coil device according to claim 8, wherein the first intermediate flange and the second intermediate flange are provided with a terminal block connection portion for connecting the flanges in a spanning manner.

11. 11. The coil device according to claim 8, wherein the first cylinder located near the intermediate first flange is provided with an auxiliary first flange.

12. A coil device as described in any one of claims 1 to 11, wherein the shape of the intermediate core when viewed from a direction along the first axis is substantially identical to the shape of the first core or the second core when viewed from a direction along the first axis.

13. The first core has a first base to which a base end of the first middle leg is connected, the first base has a pair of first support protrusions that protrude along a third axis that is substantially perpendicular to both the first axis and the second axis and that support a portion of a load of the coil device; A first support-side recess is formed between the pair of first support protrusions, the second core has a second base to which a base end of the second center leg is connected, the second base has a pair of second support protrusions that protrude along the third axis and receive a portion of the load of the coil device; A second support-side recess is formed between the pair of second support protrusions, a pair of first opposite side protrusions protruding along the third axis in a direction opposite to the first support protrusions, A first opposite-side recess is formed between the pair of first opposite-side protrusions, a protruding height of the first support protrusion along the third axis is smaller than a protruding height of the first opposite side protrusion along the third axis, a pair of second opposite side protrusions protruding along the third axis in a direction opposite to the second support protrusions, A second opposite-side recess is formed between the pair of second opposite-side protrusions, A protruding height of the second support protrusion along the third axis is smaller than a protruding height of the second opposite side protrusion along the third axis. The coil device according to claim 1 .

14. The intermediate core has an intermediate base and an intermediate support protrusion, the intermediate base has a pair of intermediate support protrusions protruding from the intermediate base in the third axis direction so as to support a portion of the weight of the coil device, An intermediate support side recess is formed between the pair of intermediate support protrusions, the intermediate core further includes a pair of intermediate opposite-side protrusions protruding from the intermediate base along the third axis in a direction opposite to the intermediate support protrusions, A middle opposite side recess is formed between the pair of middle opposite side protrusions, A protruding height of the intermediate support protrusion from the intermediate base along the third axis is smaller than a protruding height of the intermediate opposite side protrusion from the intermediate base along the third axis. A coil device according to any one of claims 1 to 13.

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