Reactor, converter, and power conversion device

Abstract

To provide a reactor that has excellent heat dissipation and low magnetic flux leakage.SOLUTION: A reactor comprises a coil composed of a spirally wound winding and a core formed so as to pass through the inside and outside of the coil. The coil has a specific shape, a first end and a second end of the winding are drawn out in a specific direction, and a specific surface of the coil and a specific surface of the core are substantially flush.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a reactor, a converter, and a power conversion device. [Background technology]

[0002] The reactor of Patent Document 1 includes a coil and a magnetic core. The coil has a first winding portion and a second winding portion formed by a winding wound in a spiral shape. The magnetic core has a first middle core, a second middle core, a first end core, and a second end core. The first middle core is disposed inside the first winding portion. The second middle core is disposed inside the second winding portion. The first end core connects a first end of the first middle core to a first end of the second middle core. The second end core connects a second end of the first middle core to a second end of the second middle core.

[0003] The first middle core and the second middle core each have a first core surface and a second core surface facing each other. The first end core and the second end core each have a first core surface and a second core surface facing each other. The first core surface of the first end core and the first core surface of the second end core are flush with the first core surface of the first middle core and the first core surface of the second middle core. The second core surface of the first end core and the second core surface of the second end core are flush with the second core surface of the first middle core and the second core surface of the second middle core. The first end and second ends of the winding are drawn out perpendicular to the second core surface and away from the second core surface. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-351722 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the reactor of Patent Document 1, when the reactor is installed on a planar installation target, the coil comes into contact with the installation target without the first core surface of the first end core portion and the first core surface of the second end core portion coming into contact with the installation target. Since the only contact area with the installation target is the coil, it is easy to transfer heat from the coil to the installation target, but it is difficult to transfer heat from the core to the installation target. Therefore, there is a demand for the development of a reactor with excellent heat dissipation properties.

[0006] In the reactor of Patent Document 1, the vicinity of the end faces of the coil is not covered by the first end core and the second end core, and therefore magnetic flux is likely to leak from the vicinity of the end faces of the coil.

[0007] An object of the present disclosure is to provide a reactor that has excellent heat dissipation properties and is less susceptible to magnetic flux leakage. [Means for solving the problem]

[0008] The reactor of the present disclosure includes: A coil formed of a spirally wound wire; A core formed to pass through the inside and outside of the coil, A first outer peripheral shape of the coil as viewed in a first direction along an axis of the coil is rectangular, the outer circumferential surface of the coil has first and second coil faces that are aligned along each of the long sides of the first outer circumferential shape and face each other; The core is A middle core disposed inside the coil; a first end core connected to a first end of the middle core; a second end core connected to a second end of the middle core, each of the outer circumferential surfaces of the first end core and the second end core has a first core surface and a second core surface facing each other; each of the first core faces of the first end core and the second end core is substantially flush with the first coil face; The first and second ends of the winding are drawn out in directions along each of the long sides. Effect of the Invention

[0009] The reactor of the present disclosure has excellent heat dissipation properties and is less susceptible to magnetic flux leakage. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic perspective view showing the entire reactor of the first embodiment. [Diagram 2] FIG. 2 is a schematic perspective view showing the reactor of the first embodiment in an exploded state. [Diagram 3] FIG. 3 is a cross-sectional view taken along line III-III of FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. [Diagram 5] FIG. 5 is an explanatory diagram illustrating a first outer circumferential shape of a coil, a second outer circumferential shape of a first end core, a third outer circumferential shape of a middle core, and a fourth outer circumferential shape of a side core in the reactor of the first embodiment. [Figure 6] FIG. 6 is a schematic perspective view showing the entire reactor of the second embodiment. [Figure 7] FIG. 7 is a schematic perspective view showing a state in which the reactor of the second embodiment is disassembled. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII of FIG. [Figure 9] FIG. 9 is a cross-sectional view taken along line IX-IX of FIG. [Figure 10] FIG. 10 is an explanatory diagram illustrating a first outer peripheral shape of the coil, a second outer peripheral shape of the first end core, a third outer peripheral shape of the middle core, a fourth outer peripheral shape of the first side core, and a fourth outer peripheral shape of the second side core in the reactor of embodiment 2. [Figure 11] FIG. 11 is a schematic diagram showing the power supply system of a hybrid vehicle. [Figure 12] FIG. 12 is a circuit diagram showing an example of a power conversion device including a converter. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Description of the embodiments of the present disclosure First, the embodiments of the present disclosure will be listed and described.

[0012] (1) A reactor according to an embodiment of the present disclosure includes: A coil formed of a spirally wound wire; A core formed to pass through the inside and outside of the coil, A first outer peripheral shape of the coil as viewed in a first direction along an axis of the coil is rectangular, the outer circumferential surface of the coil has first and second coil faces that are aligned along each of the long sides of the first outer circumferential shape and face each other; The core is A middle core disposed inside the coil; a first end core connected to a first end of the middle core; a second end core connected to a second end of the middle core, each of the outer circumferential surfaces of the first end core and the second end core has a first core surface and a second core surface facing each other; each of the first core faces of the first end core and the second end core is substantially flush with the first coil face; The first and second ends of the winding are drawn out in directions along each of the long sides.

[0013] The reactor (1) above has excellent heat dissipation properties. The first end and second end of the winding are drawn out in the direction along each of the long sides. The first core surface of the first end core and the first core surface of the second end core are substantially flush with the first coil surface. Therefore, when the reactor (1) above is installed on a planar installation target, the first coil surface, the first core surface of the first end core, and the first core surface of the second end core can be brought into contact with the installation target without the first end and second end of the winding interfering with the installation target. The reactor (1) above can have a larger contact area with the installation target than the reactor X in which the first core surface of the first end core and the first core surface of the second end core do not contact the installation target, and only the first coil surface of the coil contacts the installation target. The reactor (1) above is more likely to transmit not only the heat of the coil but also the heat of the first end core and the second end core to the installation target than the reactor X. The reactor (1) above is easier to improve in heat dissipation performance than the reactor X above.

[0014] In the reactor of (1) above, magnetic flux is less likely to leak from the vicinity of the end faces of the coil. In the reactor of (1) above, the first core surfaces of the first end core and the second end core are each substantially flush with the first coil surface, so that the end faces of the coil are covered by the first end core and the second end core. Therefore, the reactor of (1) above is more likely to reduce leakage magnetic flux from the vicinity of the end faces of the coil than reactor Y, in which the end faces of the coil are not covered by the first end core and the second end core and are exposed from the first end core and the second end core.

[0015] The reactor (1) described above is easy to shorten the length of the reactor along the first direction. If the volumes of the first end core and the second end core are constant, the reactor (1) described above has a longer length between the first core surface and the second core surface of the first end core and a longer length between the first core surface and the second core surface of the second end core than the reactor Y described above. Therefore, if the volumes of the first end core and the second end core are constant, the reactor (1) described above is easy to shorten the length of the first end core and the second end core along the first direction than the reactor Y described above.

[0016] (2) In the reactor described in (1) above, The second core faces of the first end core and the second end core may each be substantially flush with the second coil face.

[0017] The reactor (2) is less likely to leak magnetic flux from the vicinity of the end face of the coil compared to the reactor Z in which the only substantially flush surfaces are the first core surface of the first end core, the first core surface of the second end core, and the first coil surface. This is because the reactor (2) has a larger area of ​​the end face of the coil covered by the first end core and the second end core compared to the reactor Z. The reactor (2) has more options for the surface to be brought into contact with the installation object compared to the reactor Z. This is because the reactor (2) can bring the first coil surface, the first core surface of the first end core, and the first core surface of the second end core into contact with the installation object, and can also bring the second coil surface, the second core surface of the first end core, and the second core surface of the second end core into contact with the installation object. In the reactor (2) above, if the volumes of the first end core and the second end core are constant, it is easier to make the lengths of the first end core and the second end core along the first direction shorter than in the reactor Y above, and therefore it is easier to shorten the length of the reactor along the first direction.

[0018] (3) In the reactor of (1) or (2) above, a second outer circumferential shape of the first end core and the second end core as viewed from the first direction is rectangular, The first core surface and the second core surface of each of the first end core and the second end core may be surfaces along respective long sides of the second outer peripheral shape.

[0019] In the reactor of (3) above, the first core face of the first end core and the first core face of the second end core are wide surfaces, so it is easy to increase the contact area between the reactor and an object to be installed.In the reactor of (3) above, the second core face of the first end core and the second core face of the second end core are wide surfaces, so it is easy to increase the contact area between the reactor and an object to be installed.

[0020] (4) In any of the reactors described in (1) to (3) above, the core further includes a first side core and a second side core arranged in parallel to the middle core so as to sandwich the middle core without the coil being arranged therebetween, the first end core is connected to a first end portion of the first side core and a first end portion of the second side core, The second end core may be connected to a second end of the first side core and a second end of the second side core.

[0021] The reactor of (4) above has excellent heat dissipation properties and is less susceptible to magnetic flux leakage.

[0022] (5) In the reactor of (4) above, The first side core may have a thickness less than the thicknesses of the first end core and the second end core.

[0023] In the reactor of (5) above, the first end and the second end of the winding can be drawn out without interfering with the first side core.

[0024] (6) In the reactor of (5) above, The second side core may have a thickness less than the thicknesses of the first end core and the second end core.

[0025] The reactor of (6) above has many options for the direction in which the first end and the second end of the winding are led out, because the first end and the second end of the winding can be led out without interfering with the second side core.

[0026] (7) In any of the reactors described in (1) to (3) above, The core further includes a side core arranged in parallel to the middle core without the coil being arranged therein, the first end core is connected to a first end of the side core, The second end core may be connected to a second end of the side core.

[0027] The reactor of (7) above has excellent heat dissipation properties and is less susceptible to magnetic flux leakage.

[0028] (8) In the reactor of (7) above, The outer circumferential surface of the side core has a first core surface and a second core surface facing each other, The first core surface of the side core may be substantially flush with the first coil surface.

[0029] The reactor of (8) above has excellent heat dissipation properties because the first core surface of the side core is also brought into contact with the installation object.

[0030] (9) In the reactor of (8) above, The second core surface of the side core may be substantially flush with the second coil surface.

[0031] The reactor (9) above has many options for the surface to be brought into contact with the installation target, because the reactor (9) above can bring the first coil surface, the first core surface of the first end core, the first core surface of the second end core, and the first surface of the side core into contact with the installation target, or the second coil surface, the second core surface of the first end core, the second core surface of the second end core, and the second core surface of the side core into contact with the installation target.

[0032] (10) A converter according to an embodiment of the present disclosure includes: The reactor is any one of the reactors described in (1) to (9) above.

[0033] The converter has excellent performance since it includes the reactor.

[0034] (11) A power conversion device according to an embodiment of the present disclosure, The device is equipped with the converter (10) described above.

[0035] The power conversion device has excellent performance since it includes the converter.

[0036] Details of the embodiments of the present disclosure DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the embodiments of the present disclosure will be described below with reference to the drawings. In the drawings, the same reference numerals indicate the same objects.

[0037] First Embodiment [Reactor] A reactor 1 of the first embodiment will be described with reference to Figs. 1 to 5. As shown in Fig. 1, the reactor 1 includes a coil 2 and a core 3. The coil 2 is composed of a winding 20 wound in a spiral shape. The core 3 is formed so as to pass through the inside and outside of the coil 2. The core 3 forms a magnetic path that passes through the inside and outside of the coil 2. One of the features of the reactor 1 of this embodiment is that it satisfies the following requirements (a) to (c). (a) Coil 2 has a particular shape. (b) A first end 21 and a second end 22 of the winding 20 are drawn out in a particular direction. (c) A specific surface of coil 2 and a specific surface of core 3 are flush with each other.

[0038] In the following description, a first direction D1, a second direction D2, and a third direction D3 defined as follows may be used. The first direction D1 is along the axis of the coil 2. The second direction D2 is a direction along a first long side L11, which will be described later, as shown in FIG. The third direction D3 is a direction perpendicular to both the first direction D1 and the second direction D2. The length along the second direction D2 is called the width. The length along the third direction D3 is called the thickness. The core 3 has a planar shape when viewed from the third direction D3.

[0039] [coil] As shown in FIG. 1 and FIG. 2, the number of coils 2 is one. The reactor 1 having one coil 2 is easier to mold than the reactor 1 having multiple coils 2. The reactor 1 having one coil 2 has fewer parts than the reactor 1 having multiple coils 2. Therefore, the reactor 1 having one coil 2 is superior in productivity. Since the number of coils 2 is one, the width of the reactor 1 can be made shorter than the case where multiple coils 2 are arranged in parallel in the second direction D2. The shape of the coil 2 is a rectangular tube. Since the shape of the coil 2 is a rectangular tube, the contact area between the coil 2 and the planar installation target can be easily increased compared to the case where the coil 2 is a circular tube with the same cross-sectional area. Therefore, the reactor 1 easily transfers the heat of the coil 2 to the installation target. The installation target is, for example, a cooling base. The four corners of the coil 2 are rounded. As shown in FIG. 5, the first outer peripheral shape C1 of the coil 2 viewed from the first direction D1 is rectangular. That is, the end face shape of the coil 2 when viewed from the first direction D1 is a rectangular frame shape. Fig. 5 shows a state in which the reactor 1 is cut at the same position as in Fig. 4. For ease of explanation, the first outer peripheral shape C1 shown in Fig. 5 is shown by a two-dot chain line that is larger than the outer peripheral contour line of the coil 2 to distinguish it from the outer peripheral contour line of the coil 2. This point is also the same in Fig. 10 referred to in the second embodiment.

[0040] As shown in Fig. 3, the outer peripheral surface of the coil 2 has a first coil surface 251 and a second coil surface 252 facing each other. The first coil surface 251 is aligned along a first long side L11 of the rectangular first outer peripheral shape C1 shown in Fig. 5. The second coil surface 252 is aligned along a second long side L12 of the rectangular first outer peripheral shape C1 shown in Fig. 5. The first coil surface 251 and the second coil surface 252 are flat surfaces.

[0041] The winding 20 constituting the coil 2 is a series of windings without joints, as shown in Figs. 1 and 2. The winding 20 is a known winding. The winding 20 of this embodiment uses a coated rectangular wire. The conductor wire of the coated rectangular wire is made of a rectangular copper wire. The insulating coating of the coated rectangular wire is made of enamel. The coil 2 of this embodiment is made of a coated rectangular wire wound edgewise. Unlike this embodiment, the coil 2 may be made of a coated rectangular wire wound flatwise.

[0042] The first end 21 of the winding 20 is drawn out at a first end in the first direction D1 of the coil 2 in a direction along a first long side L11 of the rectangular first outer peripheral shape C1 shown in FIG. 5, i.e., in a direction along a first coil surface 251 shown in FIG. 1 and FIG. 2. The second end 22 of the winding 20 is drawn out at a second end in the first direction D1 of the coil 2 in a direction along a second long side L12 of the rectangular first outer peripheral shape C1 shown in FIG. 5, i.e., in a direction along a second coil surface 252 shown in FIG. 1 and FIG. 2. The first end 21 and the second end 22 are drawn out in the same direction. The first end 21 and the second end 22 are drawn out so as to move away from a side core 32 described later.

[0043] Although not shown in the figure, the insulating coating is stripped off from the first end 21 and the second end 22 to expose the conductor wire. A terminal member is connected to the exposed conductor wire. The terminal member is not shown in the figure. An external device is connected to the coil 2 by this terminal member. The external device is not shown in the figure. The external device is, for example, a power source that supplies power to the coil 2.

[0044] [core] 1, the planar shape of the core 3 is O-shaped. The core 3 has a first end core 35, a second end core 36, a middle core 31, and a side core 32, as shown in FIGS.

[0045] (First end core, second end core) The first end core 35 connects a first end of the middle core 31 to a first end of the side core 32. The second end core 36 connects a second end of the middle core 31 to a second end of the side core 32. The first end core 35 and the second end core 36 have the same shape. The first end core 35 and the second end core 36 are shaped like a quadrangular prism.

[0046] In this embodiment, as shown in FIG. 5, the second outer peripheral shape C2 of the first end core 35 as viewed from the first direction D1 is rectangular. For convenience of explanation, the second outer peripheral shape C2 shown in FIG. 5 is shown by a two-dot chain line larger than the outer peripheral contour line of the first end core 35 to distinguish it from the outer peripheral contour line of the first end core 35. This point is also the same in FIG. 10 referred to in the second embodiment. Although not shown, the second outer peripheral shape of the second end core 36 as viewed from the first direction D1 is also rectangular. Although the four corners of the second outer peripheral shape C2 are angular, they may be rounded. As shown in FIG. 4 and FIG. 5, the width of the first end core 35 is larger than the thickness of the first end core 35. The width of the second end core 36 is larger than the thickness of the second end core 36. The width of the first end core 35 and the width of the second end core 36 are the same. The thickness of the first end core 35 and the thickness of the second end core 36 are the same.

[0047] The outer peripheral surface of the first end core 35 has a first core surface 351 and a second core surface 352 facing each other, as shown in Fig. 3 and Fig. 4. The first core surface 351 is along a first long side L21 of the rectangular second outer peripheral shape C2 shown in Fig. 5. The second core surface 352 is along a second long side L22 of the rectangular second outer peripheral shape C2 shown in Fig. 5. In this embodiment, the planar shape of the first core surface 351 and the second core surface 352 is a trapezoidal shape narrowing from a first end surface proximal to the middle core 31 and the side core 32 of the first end core 35 toward a second end surface distal to the middle core 31 and the side core 32, as shown in Fig. 1 and Fig. 2.

[0048] The outer peripheral surface of the second end core 36 has a first core surface 361 and a second core surface 362 facing each other, as shown in Figs. 2 and 3. The first core surface 361 is along a first long side of the rectangular second outer peripheral shape. The second core surface 362 is along a second long side of the rectangular second outer peripheral shape. In this embodiment, the planar shapes of the first core surface 361 and the second core surface 362 are trapezoidal shapes that narrow from a first end surface proximal to the middle core 31 and the side core 32 of the second end core 36 toward a second end surface distal to the middle core 31 and the side core 32, as shown in Figs. 1 and 2.

[0049] As shown in FIG. 3, the first core surface 351 and the first core surface 361 are substantially flush with the first coil surface 251. By being substantially flush, the maximum difference between the first core surface 351 and the first core surface 361 and the first coil surface 251 along the third direction D3 can be reduced, and the maximum difference can be brought close to 0 (zero). As described above, the first end 21 and the second end 22 of the reactor 1 are drawn out in the direction along the first long side L11 and the second long side L12 of the rectangular first outer peripheral shape C1 shown in FIG. 5, and the first coil surface 251, the first core surface 351, and the first core surface 361 are flush with each other. Therefore, when the reactor 1 is installed on a planar installation target, the first coil surface 251, the first core surface 351, and the first core surface 361 can be brought into contact with the installation target without the first end 21 and the second end 22 interfering with the installation target. Therefore, reactor 1 can have a larger contact area between reactor 1 and the object on which it is installed, compared to reactor X in which first core surface 351 and first core surface 361 do not come into contact with the object on which it is installed and only first coil surface 251 comes into contact with the object on which it is installed.

[0050] In particular, the first core surface 351 and the second core surface 352 are wide surfaces that are aligned along the first long side L21 and the second long side L22 of the rectangular second outer peripheral shape C2 shown in Fig. 5, and therefore the contact area with the installation target can be increased. In the reactor 1, not only the heat of the coil 2 but also the heat of the first end core 35 and the second end core 36 are easily transferred to the installation target, compared to the reactor X. Therefore, the reactor 1 is easier to improve the heat dissipation, compared to the reactor X. That is, the fact that the first core surface 351 and the first core surface 361 are substantially flush with the first coil surface 251 shown in Fig. 3 means that the thicknesses of the first end core 35, the second end core 36, and the coil 2 are dimensions that easily ensure heat dissipation. The flatness of the first core surface 351, the first core surface 361, and the first coil surface 251, which are substantially flush, may be, for example, 0.4 mm or less, further, 0.2 mm or less, 0.1 mm or less, or 0.05 mm or less. The flatness here complies with JIS B 0621:1984 Definition and indication of geometric deviation.

[0051] In the reactor 1, the first core surface 351 and the first core surface 361 are substantially flush with the first coil surface 251, so that the end surface of the coil 2 is covered by the first end core 35 and the second end core 36. That is, the end surface of the coil 2 faces the first end core 35 and the second end core 36. Therefore, the reactor 1 is more likely to reduce leakage magnetic flux from the vicinity of the end surface of the coil 2 than the reactor Y in which the end surface of the coil 2 is not covered by the first end core 35 and the second end core 36 and is exposed from the first end core 35 and the second end core 36. Therefore, the reactor 1 is less susceptible to magnetic flux leakage from the vicinity of the end surface of the coil 2 than the reactor Y.

[0052] In this embodiment, the second core surface 352 and the second core surface 362 are substantially flush with the second coil surface 252. By being substantially flush, the maximum difference between the second core surface 352 and the second core surface 362 and the second coil surface 252 along the third direction D3 can be reduced, and the maximum difference can be brought closer to 0 (zero). In the reactor 1, magnetic flux is less likely to leak from the vicinity of the end surface of the coil 2 compared to the reactor Z in which the first core surface 351, the first core surface 361, and the first coil surface 251 are the only surfaces that are substantially flush. This is because, in the reactor 1, the area in which the end surface of the coil 2 is covered by the first end core 35 and the second end core 36 is larger compared to the reactor Z. That is, the area in which the end surface of the coil 2 faces the first end core 35 and the second end core 36 is larger. In the reactor 1, there are more options for the surface to be brought into contact with the installation target compared to the reactor Z. This is because the reactor 1 can have the first coil surface 251, the first core surface 351, and the first core surface 361 in contact with the installation target, and can also have the second coil surface 252, the second core surface 352, and the second core surface 362 in contact with the installation target. The fact that the second core surface 352 and the second core surface 362 shown in FIG. 3 are substantially flush with the second coil surface 252 means that the thicknesses of the first end core 35, the second end core 36, and the coil 2 are dimensions that easily ensure heat dissipation. The flatness of the second core surface 352, the second core surface 362, and the second coil surface 252 that are substantially flush with each other may be, for example, 0.4 mm or less, and may further be 0.2 mm or less, 0.1 mm or less, or 0.05 mm or less. Unlike this embodiment, the second core surface 352 and the second core surface 362 do not have to be flush with the second coil surface 252.

[0053] (Middle Core) As shown in FIG. 1, FIG. 3, and FIG. 4, the middle core 31 has a portion disposed inside the coil 2. The shape of the middle core 31 in this embodiment corresponds to the inner peripheral contour shape of the coil 2. The middle core 31 is shaped like a quadrangular prism. As shown in FIG. 5, the third outer peripheral shape C3 of the middle core 31 as viewed from the first direction D1 is rectangular. For convenience of explanation, the third outer peripheral shape C3 shown in FIG. 5 is shown by a two-dot chain line larger than the outer peripheral contour line of the middle core 31 to distinguish it from the outer peripheral contour line of the middle core 31. This point is also the same in FIG. 10 referred to in the second embodiment. Each of the four corners of the third outer peripheral shape C3 is rounded so as to follow each of the four corners of the inner peripheral surface of the coil 2. The middle core 31 and the side core 32 are arranged in parallel along the first long side L31 of the third outer peripheral shape C3.

[0054] The width of the middle core 31 is greater than the thickness of the middle core 31. In this embodiment, the width of the middle core 31 is greater than the width of the side core 32. In the reactor 1, the coil 2 is arranged in the middle core 31 that is wider than the side core 32, and therefore the width of the coil 2 is greater than that of the reactor W in which the coil 2 is arranged in the middle core 31 that has the same width as the side core 32. When the reactor 1 is installed on a planar installation target, the wide surface of the coil 2 comes into contact with the installation target. Therefore, the reactor 1 can have a larger contact area between the coil 2 and the installation target than the reactor W. The reactor 1 can easily transfer heat from the coil 2 to the installation target than the reactor W. Therefore, the reactor 1 has excellent heat dissipation properties. In the reactor 1, the coil 2 is arranged in the middle core 31 that is wider than the side core 32, and therefore the cross-sectional area of ​​the coil 2 can be larger than that of the reactor W. Therefore, in the reactor 1, the inductance can be easily increased even though the number of coils 2 is one, compared to the reactor W. Thus, the reactor 1 has excellent inductance. The thickness of the middle core 31 is smaller than the thickness of the first end core .

[0055] The outer peripheral surface of the middle core 31 has a first core surface 311 and a second core surface 312 facing each other. The first core surface 311 is aligned along a first long side L31 of a rectangular third outer peripheral shape C3 shown in FIG. 5. The second core surface 312 is aligned along a second long side L32 of the rectangular third outer peripheral shape C3 shown in FIG. 5. As shown in FIGS. 1 to 3, the middle core 31 of this embodiment is composed of two core portions, a first middle core portion 31f and a second middle core portion 31s. Unlike this embodiment, the middle core 31 may be composed of a single member.

[0056] (Side core) As shown in Figs. 1 and 2, the side core 32 is arranged in parallel to the middle core 31 without the coil 2 being arranged thereon. The side core 32 has a rectangular prism shape. As shown in Fig. 5, the fourth outer peripheral shape C4 of the side core 32 is rectangular when viewed from the first direction D1. For ease of explanation, the fourth outer peripheral shape C4 shown in Fig. 5 is shown by a two-dot chain line larger than the outer peripheral contour line of the side core 32 in order to distinguish it from the outer peripheral contour line of the side core 32. This is also true in Fig. 10 referred to in the second embodiment. Although the four corners of the fourth outer peripheral shape C4 are angular, they may be rounded.

[0057] In this embodiment, the width of the side core 32 is smaller than the width of the middle core 31. Unlike this embodiment, the width of the side core 32 may be equal to the width of the middle core 31. In this embodiment, the width of the side core 32 is larger than the thickness of the side core 32. Unlike this embodiment, the width of the side core 32 may be equal to the thickness of the side core 32. The thickness of the side core 32 in this embodiment is larger than the thickness of the middle core 31. Unlike this embodiment, the thickness of the side core 32 may be equal to the thickness of the middle core 31. The thickness of the side core 32 in this embodiment is the same as the thickness of the first end core 35 and the thickness of the second end core 36. Unlike this embodiment, the thickness of the side core 32 may be smaller than the thickness of the first end core 35 and the thickness of the second end core 36.

[0058] 2 and 4, the outer circumferential surface of the side core 32 has a first core surface 321 and a second core surface 322 facing each other. The first core surface 321 is aligned along a first long side L41 of the rectangular fourth outer circumferential shape C4 shown in Fig. 5. The second core surface 322 is aligned along a second long side L42 of the rectangular fourth outer circumferential shape C4 shown in Fig. 5.

[0059] The first core surface 321 of this embodiment is substantially flush with the first coil surface 251. That is, the first core surface 321 of this embodiment is substantially flush with the first core surface 351 and the first core surface 361 as shown in FIG. 1. By being substantially flush, the maximum difference between the first core surface 321 and the first coil surface 251 along the third direction D3 can be reduced, and the maximum difference can be brought closer to 0 (zero). The reactor 1 has excellent heat dissipation properties because the first core surface 321 is also brought into contact with the installation target. The flatness of the first core surface 321, which is substantially flush with the first coil surface 251, may be, for example, 0.4 mm or less, and may further be 0.2 mm or less, 0.1 mm or less, or 0.05 mm or less. Unlike this embodiment, the first core surface 321 does not have to be flush with the first coil surface 251.

[0060] As shown in FIG. 4, the second core surface 322 of this embodiment is substantially flush with the second coil surface 252. That is, the second core surface 322 of this embodiment is substantially flush with the second core surface 352 and the second core surface 362. By being substantially flush, the maximum difference between the second core surface 322 and the second coil surface 252 along the third direction D3 can be reduced, and the maximum difference can be brought closer to 0 (zero). The reactor 1 has many options for the surface to be brought into contact with the installation target. This is because the reactor 1 can bring the first coil surface 251, the first core surface 351, the first core surface 361, and the first core surface 321 into contact with the installation target, and can also bring the second coil surface 252, the second core surface 352, the second core surface 362, and the second core surface 322 into contact with the installation target. The flatness of the second core surface 322, which is substantially flush with the second coil surface 252, may be, for example, 0.4 mm or less, or may further be 0.2 mm or less, 0.1 mm or less, or 0.05 mm or less. Unlike the present embodiment, the second core surface 322 does not have to be flush with the second coil surface 252.

[0061] As shown in FIG. 1, the length of the side core 32 along the first direction D1 is longer than the length of the middle core 31 along the first direction D1. The length of the middle core 31 along the first direction D1 does not include the length of a gap portion 3g described later along the first direction D1. The same applies to the lengths of the other cores. The length of the middle core 31 along the first direction D1 is the total length of the length of a first middle core portion 31f described later along the first direction D1 and the length of a second middle core portion 31s along the first direction D1. The side core 32 of this embodiment is composed of two core portions, a first side core portion 32f and a second side core portion 32s. The length of the side core 32 along the first direction D1 is the total length of the length of a first side core portion 32f described later along the first direction D1 and the length of a second side core portion 32s along the first direction D1. Unlike this embodiment, the side core 32 may be composed of a single member.

[0062] As shown in FIG. 1 and FIG. 2, the core 3 of this embodiment is an assembly of a first core 3f and a second core 3s. The combination of the first core 3f and the second core 3s can be various combinations by appropriately selecting the shape of the first core 3f and the shape of the second core 3s. The shape of the first core 3f and the shape of the second core 3s may be symmetrical or asymmetrical. Symmetrical means that the shapes and sizes are the same. Asymmetrical means that the shapes are different. In this embodiment, the shape of the first core 3f and the shape of the second core 3s are symmetrical. In this embodiment, the first core 3f and the second core 3s are divided along the first direction D1. In this embodiment, the combination of the first core 3f and the second core 3s is a UU type. Although not shown in the figure, unlike this embodiment, the above combination may be a UI type, a JL type, a JJ type, or an LL type. The reactor 1 can be constructed by combining the first core 3f and the second core 3s with respect to the coil 2 along the axis of the coil 2. Therefore, the reactor 1 has excellent manufacturing workability. A gap portion 3g, which will be described later, may be provided between the first core 3f and the second core 3s, or the gap portion 3g may not be provided.

[0063] (First Core) The first core 3f has at least one selected from the group consisting of at least a part of the middle core 31 and at least a part of the side core 32, and a first end core 35. For example, when the first core 3f has at least a part of the middle core 31 or at least a part of the side core 32, and a first end core 35, the planar shape of the first core 3f is L-shaped. When the first core 3f has at least a part of the middle core 31, at least a part of the side core 32, and a first end core 35, the planar shape of the first core 3f is U-shaped or J-shaped. When the length of the part of the middle core 31 and the part of the side core 32 along the first direction D1 are the same, the planar shape of the first core 3f is U-shaped. When the length of the part of the middle core 31 and the part of the side core 32 along the first direction D1 are different from each other, the planar shape of the first core 3f is J-shaped.

[0064] The first core 3f of this embodiment has a U-shaped planar shape. The first core 3f of this embodiment has a first middle core portion 31f, a first side core portion 32f, and a first end core 35. The first core 3f is an integrally molded body of the first middle core portion 31f, the first side core portion 32f, and the first end core 35. For convenience of explanation, the boundary between the first side core portion 32f and the first end core 35 is shown by a two-dot chain line in Figs. 1 and 2. The first end core 35 connects the first middle core portion 31f and the first side core portion 32f. The first middle core portion 31f and the first side core portion 32f are provided at both ends of the first end core 35 in the width direction.

[0065] (Second core) Depending on the combination of the first core 3f and the second core 3s, the second core 3s may be composed of only the second end core 36, or may have at least one selected from the group consisting of the remainder of the middle core 31 and the remainder of the side core 32 and the second end core 36. For example, when the second core 3s is composed of one second end core 36, the planar shape of the second core 3s is I-shaped. When the second core 3s has the remainder of the middle core 31 or the remainder of the side core 32 and the second end core 36, the planar shape of the second core 3s is L-shaped. When the second core 3s has the remainder of the middle core 31, the remainder of the side core 32, and the second end core 36, the planar shape of the second core 3s is U-shaped or J-shaped. When the lengths of the remainder of the middle core 31 and the remainder of the side core 32 along the first direction D1 are the same, the planar shape of the second core 3s is U-shaped. When the remaining portion of the middle core 31 and the remaining portion of the side core 32 have different lengths in the first direction D1, the second core 3s has a J-shape in plan view.

[0066] The second core 3s of this embodiment has a U-shaped planar shape. The second core 3s of this embodiment has a second middle core portion 31s, a second side core portion 32s, and a second end core 36. The second core 3s is an integrally molded body of the second middle core portion 31s, the second side core portion 32s, and the second end core 36. For convenience of explanation, the boundary between the second side core portion 32s and the second end core 36 is shown by a two-dot chain line in Figs. 1 and 2. The second end core 36 connects the second middle core portion 31s and the second side core portion 32s. The second middle core portion 31s and the second side core portion 32s are provided at both ends of the second end core 36 in the width direction.

[0067] In this embodiment, the length of the first middle core portion 31f along the first direction D1 is shorter than the length of the first side core portion 32f along the first direction D1.

[0068] Unlike the present embodiment, the length of the first middle core portion 31f along the first direction D1 may be longer than the length of the second middle core portion 31s along the first direction D1. The length of the first side core portion 32f along the first direction D1 may be longer than the length of the second side core portion 32s along the first direction D1. The length of the first middle core portion 31f along the first direction D1 may be equal to the length of the first side core portion 32f along the first direction D1.

[0069] In this embodiment, the first core 3f and the second core 3s are combined so that the end face of the first side core portion 32f and the end face of the second side core portion 32s are in contact with each other. When combined in this manner, the above-mentioned length relationship is satisfied, and therefore a gap is provided between the end face of the first middle core portion 31f and the end face of the second middle core portion 31s. A gap portion 3g is formed between the end face of the first middle core portion 31f and the end face of the second middle core portion 31s. The gap portion 3g is formed of a member made of a material having a smaller relative magnetic permeability than the first core 3f and the second core 3s. The gap portion 3g is formed of a resin similar to the resin of the composite material molded body described later. The gap portion 3g may be formed of a mixed material in which the above-mentioned resin contains a filler described later.

[0070] Each of the first core 3f and the second core 3s is made of a composite material molded body or a powder compact. In this embodiment, the first core 3f is made of a composite material molded body, and the second core 3s is made of a powder compact. Unlike this embodiment, both the first core 3f and the second core 3s may be made of a composite material molded body or may be made of a powder compact.

[0071] The composite material compact is a compact in which soft magnetic powder is dispersed in resin. The composite material compact is obtained by filling a mold with a fluid material in which soft magnetic powder is dispersed in unsolidified resin, and solidifying the resin. The composite material compact allows easy adjustment of the content of soft magnetic powder in the resin. Therefore, the magnetic properties of the composite material compact are easy to adjust. Furthermore, the composite material compact is easier to form into a complex shape than a pressed powder compact. The content of soft magnetic powder in the composite material compact is, for example, 20% by volume or more and 80% by volume or less. The content of resin in the composite material compact is, for example, 20% by volume or more and 80% by volume or less. These contents are percentages relative to the volume of the composite material compact being 100%.

[0072] A powder compact is a compact formed by compressing and molding soft magnetic powder. Compared to a composite material compact, the powder compact can have a higher ratio of soft magnetic powder in the core. Therefore, the powder compact can easily have improved magnetic properties. Examples of magnetic properties include relative permeability and saturation magnetic flux density. Also, compared to a composite material compact, the powder compact has a smaller amount of resin and a larger amount of soft magnetic powder, and therefore has excellent heat dissipation properties. The content of soft magnetic powder in the powder compact is, for example, 85 volume % or more and 99 volume % or less. This content is a ratio relative to the volume of the powder compact being 100%.

[0073] The particles constituting the soft magnetic powder are, for example, soft magnetic metal particles, coated particles, or soft magnetic nonmetal particles. The coated particles include a soft magnetic metal particle and an insulating coating provided on the outer periphery of the soft magnetic metal particle. The soft magnetic metal is, for example, pure iron or an iron-based alloy. The iron-based alloy is, for example, an Fe-Si alloy or an Fe-Ni alloy. The insulating coating is, for example, a phosphate. The soft magnetic nonmetal is, for example, a ferrite.

[0074] The resin of the composite material molded body is, for example, a thermosetting resin or a thermoplastic resin. The thermosetting resin is, for example, an epoxy resin, a phenolic resin, a silicone resin, or a urethane resin. The thermoplastic resin is, for example, a polyphenylene sulfide resin, a polyamide resin, a liquid crystal polymer, a polyimide resin, or a fluororesin. The polyamide resin is, for example, nylon 6, nylon 66, or nylon 9T.

[0075] The composite material compact may contain a filler, such as alumina or silica, which contributes to improving heat dissipation and electrical insulation.

[0076] The content of soft magnetic powder in the composite material compact and the content of soft magnetic powder in the powder compact are considered to be equivalent to the area ratio of the soft magnetic powder in the cross section of the compact. The content of soft magnetic powder in the compact is determined as follows. The cross section of the compact is observed with a SEM (scanning electron microscope) to obtain an observation image. The cross section of the compact may be any cross section. The magnification of the SEM is 200 times or more and 500 times or less. At least 10 observation images are obtained. The total cross section is 0.1 cm2. 2 That is all. One observation image may be acquired per cross section, or multiple observation images may be acquired per cross section. Each acquired observation image is subjected to image processing to extract particle contours. Image processing includes, for example, binarization processing. The area ratio of soft magnetic particles in each observation image is calculated, and the average value of the area ratios is obtained. The average value is regarded as the content of soft magnetic powder.

[0077] Second Embodiment A reactor 1 according to a second embodiment will be described with reference to Fig. 6 to Fig. 10. The reactor 1 according to the second embodiment differs from the reactor 1 according to the first embodiment in that the combination of the first core 3f and the second core 3s is an EE type. That is, the planar shape of the first core 3f and the planar shape of the second core 3s in the second embodiment are E-shaped. The following description will focus on the differences from the first embodiment. Descriptions of the same configurations and effects as those in the first embodiment will be omitted.

[0078] [coil] As shown in Figures 6 and 7, the first end 21 of the winding 20 is drawn out at a first end in the first direction D1 of the coil 2 in a direction along the first long side L11 of the rectangular first outer peripheral shape C1 shown in Figure 10, i.e., in a direction along the first coil surface 251 shown in Figures 6 and 7. The second end 22 of the winding 20 is drawn out at a second end in the first direction D1 of the coil 2 in a direction along the second long side L12 of the rectangular first outer peripheral shape C1 shown in Figure 10, i.e., in a direction along the second coil surface 252 shown in Figure 7. The first end 21 and the second end 22 are drawn out so as to move away from the second side core 34.

[0079] [core] As shown in Fig. 6, the planar shape of the core 3 is a θ-shape. As shown in Figs. 6 and 7, the core 3 has a first end core 35, a second end core 36, a middle core 31, a first side core 33, and a second side core 34.

[0080] (First end core, second end core) The first end core 35 connects a first end of the middle core 31, a first end of the first side core 33, and a first end of the second side core 34. The second end core 36 connects a second end of the middle core 31, a second end of the first side core 33, and a second end of the second side core 34. The shapes and the second outer peripheral shape C2 of the first end core 35 and the second end core 36 of this embodiment are the same as those of the first end core 35 and the second end core 36 of the first embodiment. The relationship between the width and the thickness of the first end core 35 and the second end core 36 of this embodiment is the same as that of the first end core 35 and the second end core 36 of the first embodiment.

[0081] As shown in FIG. 8, the first core surface 351 of the first end core 35 and the first core surface 361 of the second end core 36 are substantially flush with the first coil surface 251. By being substantially flush, the difference between the first core surface 351 and the first core surface 361 and the first coil surface 251 along the third direction D3 can be reduced, and the maximum difference can be brought closer to 0 (zero). The flatness of the first core surface 351, the first core surface 361, and the first coil surface 251 that are substantially flush may be, for example, 0.4 mm or less, and may further be 0.2 mm or less, 0.1 mm or less, or 0.05 mm or less. In this embodiment, the second core surface 352 of the first end core 35 and the second core surface 362 of the second end core 36 are substantially flush with the second coil surface 252. Being substantially flush, the difference in the third direction D3 between the second core surface 352 and the second core surface 362 and the second coil surface 252 can be reduced, and the maximum difference can be brought closer to 0 (zero). The flatness of the second core surface 352, the second core surface 362, and the second coil surface 252, which are substantially flush, may be, for example, 0.4 mm or less, and may further be 0.2 mm or less, 0.1 mm or less, or 0.05 mm or less. Unlike this embodiment, the second core surface 352 and the second core surface 362 may not be flush with the second coil surface 252.

[0082] (Middle Core) As shown in Figs. 6 and 7, the middle core 31 has a quadrangular prism shape corresponding to the inner peripheral contour shape of the coil 2. As shown in Fig. 10, the third outer peripheral shape C3 of the middle core 31 when viewed from the first direction D1 is rectangular. As shown in Figs. 9 and 10, the width of the middle core 31 is greater than the thickness of the middle core 31. The width of the middle core 31 is greater than the width of the first side core 33 and the width of the second side core 34. The thickness of the middle core 31 is less than the thickness of the first end core 35 and the thickness of the second end core 36. The middle core 31 of this embodiment is composed of two core portions, a first middle core portion 31f and a second middle core portion 31s.

[0083] (First side core, second side core) As shown in FIG. 6 and FIG. 7, the first side core 33 and the second side core 34 are arranged in parallel to the middle core 31 so as to sandwich the middle core 31 without the coil 2 being arranged therebetween. The first side core 33 and the second side core 34 are arranged facing each other. The first side core 33 and the second side core 34 are arranged on the outer periphery of the coil 2. The first side core 33 and the second side core 34 have the same shape. The first side core 33 and the second side core 34 are each shaped like a quadrangular prism. In this embodiment, as shown in FIG. 10, the fourth outer periphery shape C4 of the first side core 33 and the second side core 34 is square when viewed from the first direction D1. Unlike this embodiment, each of the fourth outer periphery shapes C4 may be rectangular.

[0084] As shown in FIG. 9 and FIG. 10, the width of the first side core 33 is the same as the thickness of the first side core 33. The width of the second side core 34 is the same as the thickness of the second side core 34. In this embodiment, the thickness of the first side core 33 and the thickness of the second side core 34 are each the same as the thickness of the middle core 31. Unlike this embodiment, the thickness of the first side core 33 may be the same as the thickness of the middle core 31, and the thickness of the second side core 34 may be greater than the thickness of the middle core 31. In this embodiment, the thickness of the first side core 33 and the thickness of the second side core 34 are each smaller than the thickness of the first end core 35 and the thickness of the second end core 36. Unlike this embodiment, the thickness of the first side core 33 may be smaller than the thickness of the first end core 35 and the thickness of the second end core 36, and the thickness of the second side core 34 may be the same as the thickness of the first end core 35 and the thickness of the second end core 36.

[0085] As shown in Figures 7 and 9, the outer circumferential surface of the first side core 33 has a first core surface 331 and a second core surface 332 facing each other. The first core surface 331 and the second core surface 332 are aligned along the second direction D2 as shown in Figure 9. As shown in Figures 7 and 9, the outer circumferential surface of the second side core 34 has a first core surface 341 and a second core surface 342 facing each other. The first core surface 341 and the second core surface 342 are aligned along the second direction D2 as shown in Figure 9.

[0086] The first core surface 331 is not flush with the first coil surface 251, as shown in FIG. 9. The first core surface 331 is not flush with the first core surface 351 either. The first core surface 331 is not flush with the first core surface 361 either, as shown in FIG. 6 and FIG. 7. The first core surface 331 is flush with the first core surface 311 as shown in FIG. The second core surface 332 is not flush with the second coil surface 252 either. The second core surface 332 is not flush with the second core surface 352 either. The second core surface 332 is not flush with the second core surface 362 either, as shown in FIG. 6. The second core surface 332 is flush with the second core surface 312 as shown in FIG. 9.

[0087] In this embodiment, first core surface 341 is not flush with first coil surface 251. First core surface 341 is not flush with first core surface 351. First core surface 341 is not flush with first core surface 361. First core surface 341 is flush with first core surface 311. Second core surface 342 is not flush with second coil surface 252. Second core surface 342 is not flush with second core surface 352. Second core surface 342 is not flush with second core surface 362. Second core surface 342 is flush with second core surface 312.

[0088] Unlike this embodiment, first core face 341 may be substantially flush with first coil face 251. First core face 341 may be substantially flush with first core face 351. First core face 341 may be substantially flush with first core face 361. Second core face 342 may be substantially flush with second coil face 252. Second core face 342 may be substantially flush with second core face 352. Second core face 342 may be substantially flush with second core face 362.

[0089] As shown in FIG. 6, the length of the first side core 33 along the first direction D1 and the length of the second side core 34 along the first direction D1 are longer than the length of the middle core 31 along the first direction D1. The length of the middle core 31 along the first direction D1 is the total length of the length of the first middle core portion 31f along the first direction D1, which will be described later, and the length of the second middle core portion 31s along the first direction D1. In this embodiment, the first side core 33 is composed of two core portions, the first side core portion 33f and the first side core portion 33s. The length of the first side core 33 along the first direction D1 is the total length of the length of the first side core portion 33f along the first direction D1, which will be described later, and the length of the first side core portion 33s along the first direction D1. In this embodiment, the second side core 34 is composed of two core portions, the second side core portion 34f and the second side core portion 34s. The length of the second side core 34 along the first direction D1 is the total length of the length of a second side core portion 34f along the first direction D1, which will be described later, and the length of a second side core portion 34s along the first direction D1. Unlike this embodiment, the first side core 33 may be formed of a single member. Unlike this embodiment, the second side core 34 may be formed of a single member.

[0090] In this embodiment, as shown in Figs. 6 and 7, the combination of the first core 3f and the second core 3s is an EE type. Although not shown in the figures, unlike this embodiment, the combination may be an EI type, an ET type, an EU type, an FF type, an FL type, or a UT type. The reactor 1 can be constructed by combining the first core 3f and the second core 3s with respect to the coil 2 along the axis of the coil 2. Therefore, the reactor 1 has excellent manufacturing workability. A gap portion 3g described later may be provided between the first core 3f and the second core 3s, or the gap portion 3g may not be provided.

[0091] (First Core) The first core 3f may have at least a first end core 35. The first core 3f may have at least one selected from the group consisting of at least a part of the middle core 31, at least a part of the first side core 33, and at least a part of the second side core 34, in addition to the first end core 35. For example, when the first core 3f has at least a part of the middle core 31 and the first end core 35, the planar shape of the first core 3f is T-shaped. When the first core 3f has at least a part of the first side core 33 or at least a part of the second side core 34, and the first end core 35, the planar shape of the first core 3f is L-shaped. When the first core 3f has at least a part of the first side core 33 or at least a part of the second side core 34, at least a part of the middle core 31, and the first end core 35, the planar shape of the first core 3f is F-shaped. When the first core 3f has at least a part of the first side core 33, at least a part of the second side core 34, and the first end core 35, the planar shape of the first core 3f is U-shaped. When the first core 3f has at least a part of the middle core 31, at least a part of the first side core 33, at least a part of the second side core 34, and the first end core 35, the planar shape of the first core 3f is E-shaped.

[0092] The first core 3f of this embodiment has an E-shaped planar shape. The first core 3f of this embodiment has a first middle core portion 31f, a first side core portion 33f, a second side core portion 34f, and a first end core 35. The first core 3f is a molded body in which the first middle core portion 31f, the first side core portion 33f, the second side core portion 34f, and the first end core 35 are integrated together. The first end core 35 connects the first middle core portion 31f, the first side core portion 33f, and the second side core portion 34f. The first side core portion 33f and the second side core portion 34f are provided at both ends in the direction along the width of the first end core 35. The first middle core portion 31f is provided in the center of the first end core 35. In this embodiment, the first core 3f is composed of a molded body of a composite material.

[0093] (Second core) The second core 3s has at least a second end core 36. Depending on the combination of the first core 3f and the second core 3s, the second core 3s may have at least one selected from the group consisting of the remainder of the middle core 31, the remainder of the first side core 33, and the remainder of the second side core 34, in addition to the second end core 36. For example, when the second core 3s is composed of one second end core 36, the planar shape of the second core 3s is I-shaped. When the second core 3s has the remainder of the middle core 31 and the second end core 36, the planar shape of the second core 3s is T-shaped. When the second core 3s has the remainder of the first side core 33 or the remainder of the second side core 34 and the second end core 36, the planar shape of the second core 3s is L-shaped. When the second core 3s has the remainder of the first side core 33 or the remainder of the second side core 34, the remainder of the middle core 31, and the second end core 36, the planar shape of the second core 3s is F-shaped. When the second core 3s has the remainder of the first side core 33, the remainder of the second side core 34, and the second end core 36, the planar shape of the second core 3s is U-shaped. When the second core 3s has the remainder of the middle core 31, the remainder of the first side core 33, the remainder of the second side core 34, and the second end core 36, the planar shape of the second core 3s is E-shaped.

[0094] The second core 3s of this embodiment has an E-shaped planar shape. The second core 3s of this embodiment has a second middle core portion 31s, a first side core portion 33s, a second side core portion 34s, and a second end core 36. The second core 3s is a molded body in which the second middle core portion 31s, the first side core portion 33s, the second side core portion 34s, and the second end core 36 are integrated together. The second end core 36 connects the second middle core portion 31s, the first side core portion 33s, and the second side core portion 34s. The first side core portion 33s and the second side core portion 34s are provided at both ends in the direction along the width of the second end core 36. The second middle core portion 31s is provided in the center of the second end core 36. In this embodiment, the second core 3s is formed of a powder compact.

[0095] In this embodiment, the length of the first side core portion 33f in the first direction D1 is equal to the length of the second side core portion 34f in the first direction D1. The length of the first side core portion 33f in the first direction D1 and the length of the second side core portion 34f in the first direction D1 are longer than the length of the first middle core portion 31f in the first direction D1.

[0096] Unlike the present embodiment, the length of the first middle core portion 31f along the first direction D1 may be longer than the length of the second middle core portion 31s along the first direction D1. The length of the first side core portion 33f along the first direction D1 may be longer than the length of the first side core portion 33s along the first direction D1. The length of the second side core portion 34f along the first direction D1 may be longer than the length of the second side core portion 34s along the first direction D1. The length of the first side core portion 33f along the first direction D1 and the length of the second side core portion 34f along the first direction D1 may be equal to the length of the first middle core portion 31f along the first direction D1. The length of the first side core portion 33s along the first direction D1 and the length of the second side core portion 34s along the first direction D1 may be equal to the length of the second middle core portion 31s along the first direction D1.

[0097] The first core 3f and the second core 3s are assembled so that the end face of the first side core portion 33f is in contact with the end face of the first side core portion 33s, and the end face of the second side core portion 34f is in contact with the end face of the second side core portion 34s. When assembled in this manner, the above-mentioned length relationship is satisfied, so that a gap is provided between the end face of the first middle core portion 31f and the end face of the second middle core portion 31s. A gap portion 3g is formed between the end faces.

[0098] Third Embodiment [Converter / Power Conversion Device] The reactor 1 of the first and second embodiments can be used for applications that satisfy the following energization conditions. For example, the energization conditions include a maximum DC current of about 100 A to 1000 A, an average voltage of about 100 V to 1000 V, and a usage frequency of about 5 kHz to 100 kHz. The reactor 1 of the first and second embodiments can be used as a component of a converter mounted on a vehicle 1200, typically an electric vehicle, a hybrid vehicle, or a fuel cell vehicle, or as a component of a power conversion device including the converter.

[0099] As shown in Fig. 11, the vehicle 1200 includes a main battery 1210, a power conversion device 1100 connected to the main battery 1210, and a motor 1220 that is driven by power supplied from the main battery 1210 and used for traveling. The motor 1220 is typically a three-phase AC motor. The motor 1220 drives wheels 1250 during traveling, and functions as a generator during regeneration. In the case of a hybrid vehicle, the vehicle 1200 includes an engine 1300 in addition to the motor 1220. Fig. 11 shows an example in which the charging point of the vehicle 1200 is an inlet. Although not shown in the figure, the charging point of the vehicle 1200 may be configured to include a plug.

[0100] The power conversion device 1100 includes a converter 1110 connected to a main battery 1210, and an inverter 1120 connected to the converter 1110. The inverter 1120 converts between DC and AC. The converter 1110 shown in this example boosts the input voltage of the main battery 1210, which is about 200V to 300V, to about 400V to 700V when the vehicle 1200 is running, and supplies the power to the inverter 1120. During regeneration, the converter 1110 reduces the input voltage output from the motor 1220 to a DC voltage suitable for the main battery 1210, and charges the main battery 1210. The input voltage is a DC voltage. During the running of the vehicle 1200, the inverter 1120 converts the DC boosted by the converter 1110 into a predetermined AC voltage and supplies the AC voltage to the motor 1220. During regeneration, the inverter 1120 converts the AC output from the motor 1220 into DC and outputs it to the converter 1110 .

[0101] As shown in FIG. 12, the converter 1110 includes a plurality of switching elements 1111, a drive circuit 1112 that controls the operation of the switching elements 1111, and a reactor 1115, and converts the input voltage by repeatedly turning the switching elements 1111 on and off. The conversion of the input voltage means stepping up and down the voltage. The switching elements 1111 are power devices such as field effect transistors and insulated gate bipolar transistors. The reactor 1115 uses the properties of a coil that prevents changes in current flowing through a circuit, and has a function of smoothing the change when the current increases or decreases due to switching operation. The reactor 1115 includes the reactor 1 of the first or second embodiment. By including this reactor 1, the power conversion device 1100 and the converter 1110 have excellent performance.

[0102] In addition to the converter 1110, the vehicle 1200 includes a power supply converter 1150 connected to the main battery 1210, and an auxiliary power supply converter 1160 that converts the high voltage of the main battery 1210 to low voltage. The auxiliary power supply converter 1160 is connected to the main battery 1210 and a sub-battery 1230 that serves as a power source for the auxiliary devices 1240. The converter 1110 typically performs DC-DC conversion. The power supply converter 1150 and the auxiliary power supply converter 1160 perform AC-DC conversion. Some of the power supply converters 1150 perform DC-DC conversion. The reactors of the power supply converter 1150 and the auxiliary power supply converter 1160 may be reactors that have the same configuration as the reactor 1 of the first embodiment, and that have been appropriately modified in size or shape. Furthermore, the reactor 1 of the first or second embodiment can be used for a converter that converts input power, that is, a converter that only steps up the voltage, or a converter that only steps down the voltage.

[0103] The present invention is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0104] 1 Reactor 2 coil, 20 winding, 21 first end, 22 second end 251 first coil surface, 252 second coil surface 3 core, 3f first core, 3s second core, 3g gap section 31 middle core, 311 first core surface, 312 second core surface 31f First Middle Core Section, 31s Second Middle Core Section 32 side core, 321 first core surface, 322 second core surface 32f First side core part, 32s Second side core part 33 first side core, 331 first core surface, 332 second core surface 33f first side core part, 33s first side core part 34 second side core, 341 first core surface, 342 second core surface 34f second side core part, 34s ​​second side core part 35 first end core, 351 first core surface, 352 second core surface 36 second end core, 361 first core surface, 362 second core surface D1 first direction, D2 second direction, D3 third direction C1 First outer circumference, L11 First long side, L12 Second long side C2: Second outer circumference, L21: First long side, L22: Second long side C3 third outer circumference, L31 first long side, L32 second long side C4 fourth outer peripheral shape, L41 first long side, L42 second long side 1100 Power Converter, 1110 Converter 1111 switching element, 1112 drive circuit 1115 Reactor, 1120 Inverter 1150 Converter for power supply device, 1160 Converter for auxiliary power supply 1200 vehicle, 1210 main battery, 1220 motor 1230 Sub-battery, 1240 Auxiliary equipment 1250 wheels, 1300 engine

Claims

1. A coil formed of a spirally wound wire; A core formed to pass through the inside and outside of the coil, A first outer peripheral shape of the coil as viewed in a first direction along an axis of the coil is rectangular, the outer circumferential surface of the coil has first and second coil faces that are aligned along each of the long sides of the first outer circumferential shape and face each other; The core is A middle core disposed inside the coil; a first end core connected to a first end of the middle core; a second end core connected to a second end of the middle core, each of the outer circumferential surfaces of the first end core and the second end core has a first core surface and a second core surface facing each other; each of the first core faces of the first end core and the second end core is substantially flush with the first coil face; The first end and the second end of the winding are drawn out in a direction along each of the long sides. Reactor.

2. The reactor according to claim 1 , wherein each of the second core faces of the first end core and the second end core is substantially flush with the second coil face.

3. a second outer circumferential shape of the first end core and the second end core as viewed from the first direction is rectangular, The reactor according to claim 2 , wherein the first core surface and the second core surface of each of the first end core and the second end core are surfaces extending along respective long sides of the second outer circumferential shape.

4. the core further includes a first side core and a second side core arranged in parallel to the middle core so as to sandwich the middle core without the coil being arranged therebetween, the first end core is connected to a first end portion of the first side core and a first end portion of the second side core, The reactor according to claim 1 , wherein the second end core is connected to a second end portion of the first side core and a second end portion of the second side core.

5. The reactor according to claim 4 , wherein a thickness of the first side core is thinner than thicknesses of the first end core and the second end core.

6. The reactor according to claim 5 , wherein a thickness of the second side core is thinner than thicknesses of the first end core and the second end core.

7. The core further includes a side core arranged in parallel to the middle core without the coil being arranged therein, the first end core is connected to a first end of the side core, The reactor according to claim 1 , wherein the second end core is connected to a second end portion of the side core.

8. The outer circumferential surface of the side core has a first core surface and a second core surface facing each other, The reactor according to claim 7 , wherein the first core surface of the side core is substantially flush with the first coil surface.

9. The reactor according to claim 8 , wherein the second core surface of the side core is substantially flush with the second coil surface.

10. A reactor comprising the reactor according to claim 1 or 2. converter.

11. A converter comprising: Power conversion equipment.

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