JP2012023090A - Reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reactor capable of effectively suppressing eddy current loss due to flux leakage by a simple configuration.SOLUTION: The reactor includes: a reactor core 12 which includes two U-shaped core members 16 each having two legs 18 and is configured in an arrangement in which end faces 20 of the legs 18 of the core member 16 respectively face end faces 20 of the legs 18 of the other core member 16 across a prescribed gap; and two coils 14 respectively wound around the legs 18 of the core members 16 that face each other across the gap 24. The coils 14 are formed such that a distance between an inner periphery of the coil and the side surface 38 of the leg of the core member 16 is larger in the vicinity of the gap 24 than at both ends of the coil.

Description

  The present invention relates to a reactor, and more particularly, a reactor core formed by annularly connecting two U-shaped or U-shaped core members via a gap, and windings around the legs of each core member including the gap. It is related with a reactor provided with two coils rotated.

  Conventionally, a reactor has been used as a boost converter component for boosting a DC voltage. This reactor generally includes a reactor core in which a plurality of core members made of a magnetic material are bonded and connected in a ring shape through a nonmagnetic gap plate, and a coil wound around the connecting portion of the core member. Composed. In such a reactor, the electric energy flowing through the coil can be temporarily stored in the reactor core as magnetic energy.

  In the reactor, when the coil is energized and the reactor core is excited, leakage magnetic flux is likely to occur at the connecting portion of the core member. This leakage magnetic flux flows from the end of one core member to the end of the other core member so as to go around the outer periphery of the nonmagnetic gap plate. When such a leakage magnetic flux interlinks with a coil wound around the eddy current, an eddy current is generated in the coil and a power loss (eddy current loss) is generated.

  In order to reduce the eddy current loss, for example, in Japanese Patent Application Laid-Open No. 2008-210998 (Patent Document 1), a coil wound around a central magnetic leg (12, 12) opposed via an air gap (9) Is divided into a divided copper material 1 and a divided copper material 2, and a reactor element with an air gap is described in which a dividing point (15) which is a space portion is provided between the divided copper material 1 and the divided copper material 2. Yes.

  In addition, JP 2009-32922 A (Patent Document 2) describes a plurality of magnetic core materials (1, 2) and non-magnetic material interposed between adjacent core materials (1, 2). A gap plate (3) having a gap plate (3), wherein a facing surface of the core material (1, 2) and a facing surface of the gap plate (3) are fixed via an adhesive layer (4). Forming a leakage flux attracting and transmitting means (6) for attracting the leakage flux leaked from the core material and flowing the leakage flux to the adjacent core material on the peripheral surface other than the opposite surface of As the attracting transmission means (6), an endless protrusion of ferromagnetic material is illustrated.

JP 2008-210998A JP 2009-32922 A

  As described in Patent Document 1, when the coil wound around the central magnetic legs facing each other through the air gap is divided into two, a structure in which the divided coils are electrically connected to each other, There is a problem that a structure for individually supporting the central magnetic leg is required and the structure becomes complicated.

  In the reactor core, a leakage magnetic flux in which a ripple component is superimposed on a direct current component is generated. However, as described in Patent Document 2, the leakage magnetic flux attracting and transmitting means made of a ferromagnetic material draws the leakage magnetic flux to an adjacent core member. Since the magnetic shield cannot separate the leakage flux for each frequency component, it is necessary to take measures against all the leakage flux including the DC component. For this reason, if effective magnetic shielding is applied to all leakage flux, the structure of the magnetic shield becomes larger and the reactor core itself becomes larger. The linearity of the DC superposition characteristics of the reactor is reduced due to the non-linear magnetic characteristics of the magnetic shield. In addition, there is a problem that the structure near the gap plate becomes complicated.

  An object of the present invention is to provide a reactor that can effectively suppress eddy current loss due to leakage magnetic flux with a simple configuration.

  The reactor according to the present invention includes two U-shaped or U-shaped core members having two leg portions, and the end surfaces of the leg portions of the core member are arranged to face each other with a predetermined gap therebetween. The reactor is composed of a reactor core and two coils wound around the legs of the core members facing each other through the gap, and the coil includes an inner periphery of the coil and the core member. The distance between the leg side surfaces is larger in the vicinity of the gap than both ends of the coil.

  The reactor which concerns on this invention WHEREIN: The coil part currently formed with the said distance large may be formed in the length of 3-6 times the dimension of the said gap by making the center position between the said gaps into an axis of symmetry.

  In the reactor according to the present invention, the distance may be a maximum dimension at a position corresponding to the gap, and the maximum dimension may be 20% or more larger than the minimum dimension that is the distance at both ends of the coil.

  Further, in the reactor according to the present invention, the coil portion having a large distance is formed to have a length of 3 to 6 times the dimension of the gap with the center position between the gaps as the axis of symmetry. The distance may gradually increase or decrease between a minimum dimension and a maximum dimension in a distance change area corresponding to 30% or less of the distance, and the distance may be set to the maximum dimension outside the distance change area.

  Further, in the reactor according to the present invention, the core member has a rectangular cross-sectional shape and a leg end face shape, and is connected in an annular shape through the gap, and the inner side of the leg portion facing the inner side of the annular shape. The coil is formed such that the distance between the peripheral side surface and the inner peripheral portion of the coil is constant over the entire length of the coil, while the outer peripheral side surface of the leg portion facing the outer side of the ring and the inner periphery of the coil The distance in the vicinity of the gap may be larger than the certain dimension at both ends of the coil.

  In this case, the side defined by the end surface of the leg portion and the inner peripheral side surface so that the gap between the leg end surfaces of the core member increases as the gap approaches the inner peripheral side surface in the width direction of the leg portion. The part may be subjected to a corner process, and in the corner process, the side part may be formed as a curved surface, or the side part may be formed as a corner dropping plane.

  Furthermore, in the reactor according to the present invention, when the core member has a rectangular cross-sectional shape and a leg end face shape, the core member leg portions excluding the inner peripheral side surface and the outer peripheral side surface are arranged. About at least any one of the distance between the 1st and 2nd side surface and the said coil inner peripheral part, the dimension in the vicinity of the said gap may be formed larger than the said fixed dimension in a coil both ends.

  According to the reactor of the present invention, the coil is formed such that the distance between the inner peripheral portion of the coil and the side surface of the leg portion of the core member increases in the vicinity of the gap between the core members where leakage flux from the reactor core is likely to occur. By being formed, the amount of leakage flux linkage passing through the coil can be reduced, thereby effectively reducing eddy current loss.

  Further, if the distance between the core member legs is uniformly increased over the entire length of the coil, the resistance loss increases as the length of the conductive wire constituting the coil increases. Since the coil is formed so as to be larger than both ends of the coil in the vicinity of the gap, an increase in resistance loss due to an increase in the coil conductor length can be minimized.

  As described above, according to the reactor according to the present invention, the distance or dimension between the inner peripheral portion of the coil and the side surface of the leg portion of the core member is increased in the vicinity of the gap between the core members without performing coil division or magnetic shielding. Thus, the eddy current loss generated in the coil can be effectively suppressed with the simple configuration of forming the coil.

It is a top view of the reactor which is one embodiment (henceforth embodiment) of this invention. FIG. 2 is a partial cross-sectional view (a bobbin is omitted) of the reactor shown in FIG. 1. It is a top view of a bobbin. It is the A section enlarged view in FIG. It is the B section enlarged view in FIG. It is CC sectional view taken on the line in FIG. 2 (a core end surface is included). It is a figure which shows the confirmation result of the eddy current loss reduction of the reactor of this embodiment in comparison with a prior art example. It is a top view of the reactor which is another embodiment of this invention.

  Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings. In this description, specific shapes, materials, numerical values, directions, and the like are examples for facilitating the understanding of the present invention, and can be appropriately changed according to the application, purpose, specification, and the like.

  FIG. 1 shows an upper surface of a reactor 10 according to an embodiment of the present invention, and FIG. 2 shows a part of a cross section taken along a plane parallel to the upper surface of the reactor 10 of FIG. In FIG. 2, the bobbin 26 is not shown.

  The reactor 10 includes a reactor core 12 and two coils. The reactor core 12 is composed of two core members 16 having a substantially U-shaped or U-shaped upper surface shape. The core member 16 has two leg portions 18 and 18 projecting in parallel. When the core member 16 is viewed from the arrow X direction, the end surface 20 of each leg 18 is formed in a rectangular shape typified by a rectangle or a square. The core member 16 has the same rectangular cross section as the end face 20 from the end face of one leg 18 to the end face of the other leg 18.

  The core member 16 is made of a magnetic material having high linearity electromagnetic characteristics, and is composed of a sintered magnetic core, a dust core, a laminate of electromagnetic steel sheets, and the like. When the core member 16 is composed of a laminated body of electromagnetic steel plates such as silicon steel plates, for example, a plurality of electromagnetic steel plates punched into a substantially U shape are stacked and fixed together by a fastening method such as welding, bonding, or caulking. Alternatively, a belt-shaped electromagnetic steel sheet is wound a predetermined number of times around a winding mold having an outer shape substantially corresponding to the window 22 formed in the center of the reactor core 12, and the end is welded to the outer periphery of the wound body, etc. Each core member 16 may be formed by fixing with the above, removing the wound body from the winding mold, and dividing it into two.

  The two core members 16 are arranged so that the end surfaces 20 of the respective leg portions 18 face each other via gaps 24 having a predetermined width g, and are nonmagnetic gap plates (not shown) interposed in the respective gaps 24. By being bonded and fixed with a pinch in between, it is connected in an annular shape. The nonmagnetic gap plate can be suitably formed from ceramics, for example. In the reactor 10, the length of the core member 16 and the width g of the two gaps 24 are precisely set to realize a desired magnetic path length and inductance.

  The two coils 14 are respectively wound around the legs 18 of the core members 16 facing each other through the gap 24. One end of each coil 14 is electrically connected to each other, and the other end of each coil 14 is connected to an external terminal (not shown) of the reactor 10. The coil 14 is configured by an edgewise coil formed by winding a conductive wire made of a strip-shaped copper wire or the like. Electrical insulation is ensured between adjacent turns of the coil 14 by an insulating material such as enamel coated on itself. In addition, by electrically winding an insulating member such as insulating paper between the turns of the coil 14, the electrical insulation between the turns may be further strengthened. Furthermore, a gap is formed between adjacent turns of the coil 14, and the resin mold molding material to be applied later is filled into the gap, thereby further enhancing the electrical insulation between the turns. Also good.

  In addition, although this embodiment demonstrates the coil 14 as what is comprised by an edgewise coil, it is not limited to this, For example, a coil may be comprised by winding the conducting wire which has a circular cross section.

  The coil 14 is formed by being wound around a bobbin 26 made of an insulating resin. As shown in FIG. 3, the bobbin 26 includes a body portion 28 having a substantially rectangular cylindrical shape, and flange portions 30 and 30 integrally formed at both ends of the body portion 28. The bobbin 26 includes a receiving hole 32 that extends through the body portion 28 and the flange portion 30. The accommodation hole 32 is formed in a rectangular shape substantially corresponding to the outer shape of the leg portion 18 of the core member 16. Further, as described later, the outer peripheral portion of the body portion 28 is formed such that the gap between the inner peripheral portion of the coil 14 and the side surface of the core member 16 is formed larger than the coil end portion side portion in the coil central portion. For example, it is formed in a shape bulging in three directions. Here, the “three sides” in FIG. 3 are the right side and the near side and the back side with respect to the paper surface of FIG.

  In the bobbin 26, one or both of the flange portions 30 may be formed as separate members from the body portion 28, the flange portion may be omitted, or the bobbin itself may be omitted.

  4 is an enlarged view of a portion A in FIG. 2, FIG. 5 is an enlarged view of a portion B in FIG. 2, and FIG. 6 is a cross-sectional view taken along the line CC in FIG. 20). The bobbin 26 is not shown in FIGS.

  As shown in FIG. 6, the leg portion 18 of the core member 16 has a rectangular shape, and thus has four side surfaces connected to the end surface 20. Specifically, the four side surfaces are the inner side of the annular reactor core 12, that is, the inner peripheral side surface 36 facing the window portion 22, and the outer side of the annular reactor core 12, that is, the side opposite to the inner peripheral side surface. These are an outer peripheral side surface 38 and first and second side surfaces 40 and 42 which are connected to the inner peripheral side surface 36 and the outer peripheral side surface 38, respectively, and are parallel to each other. Hereinafter, the direction orthogonal to the inner peripheral side surface 36 and the outer peripheral side surface 38 is referred to as the width direction, the direction orthogonal to the first and second side surfaces 40 and 42 is referred to as the thickness direction, and the direction orthogonal to the end surface 20 is the length. It is called direction. The first and second side surfaces 40 and 42 will be referred to as the upper side surface 40 and the lower side surface 42 for convenience. However, when the reactor core 12 is installed such that the end surface 20 of the core member 16 is orthogonal to the vertical direction, for example, the first and second side surfaces cannot be said to be the upper side surface and the lower side surface. Please note that.

  As shown in FIG. 4, the coil 14 is formed such that the distance or dimension between the coil inner peripheral portion 44 and the outer peripheral side surface 38 of the leg portion 18 of the core member 16 is larger in the vicinity of the gap 24 than both ends of the coil. Yes. Specifically, with respect to the length direction, the coil 14 has a coil end portion 46 located at both ends and a coil central portion 48 located in the vicinity of the gap 24. The distance between the coil inner peripheral portion 44 and the outer peripheral side surface 38 of the core member 16 in the coil central portion 48 is larger than the distance between the coil inner peripheral portion 44 and the outer peripheral side surface 38 of the core member 16 in the coil end portion 46. The distance is formed large.

  In more detail in accordance with the present embodiment, the coil central portion 48 is located between the gap facing region 50 where the distance from the outer peripheral side surface 38 is constant at the maximum dimension D, and the outer peripheral side surface. The distance change region 52 is formed such that the distance gradually increases or decreases from the minimum dimension d to the maximum dimension D or vice versa. The distance d between the coil inner peripheral portion 44 and the outer peripheral side surface 38 of the core member 16 at the coil both end portions 46 substantially corresponds to the thickness dimension of the body portion 28 of the bobbin 26, and between the coil 14 and the core member 16. The dimensions are set to ensure electrical insulation.

  In other words, as compared with the coil end portion 46, the conductive wire 15 constituting the coil 14 is wound in a direction away from the leg portion 18 of the core member 16 in the distance changing region 52, and the coil 14 is wound in the gap facing region 50. Is wound for several turns at a position shifted by the maximum dimension D in a direction away from the leg portion 18 of the core member 16. Such a coil 14 is easy by prescribing the external dimensions of the body portion 28 of the bobbin 26 (when the bobbin is omitted, the external dimensions of a winding mold for winding and forming the coil 14). Can be formed.

  Here, regarding the coil 14, the maximum dimension D is preferably 20% or more larger than the minimum dimension d. Further, the coil central portion 48 that is formed to have a large distance with respect to the coil 14 is formed to have a length L that is 3 to 6 times the dimension g of the gap 24 with the central position 34 between the gaps 24 as the axis of symmetry. It is preferable. Furthermore, regarding the coil 14, the length of the distance changing region 52 preferably corresponds to 30% or less of the length L of the coil central portion 48. These numerical values related to the coil 14 take into account the balance between effectively reducing eddy current loss as described later and increasing the size of the coil 14 by winding the conductive wire 15 outward. Are preferably selected.

  In the present embodiment, the distance between the coil inner peripheral portion 44 and the outer peripheral side surface 38 of the leg portion 18 of the core member 16 is described and illustrated so as to change along the trapezoidal profile. For example, the coil may be formed such that the distance between the inner peripheral portion of the coil and the outer peripheral side surface changes along the arc-shaped profile.

  Referring to FIG. 6, the distance between the coil inner peripheral portion 44 of the coil 14 and the upper side surface 40 of the leg portion 18 of the core member 16, and the coil inner peripheral portion 44 of the coil 14 and the leg portion 18 of the core member 16. The distance between the lower side surface 42 and the lower side surface 42 is set similarly to the distance between the coil inner peripheral portion 44 and the outer peripheral side surface 38 of the leg portion 18 of the core member 16 described above.

  On the other hand, referring to FIGS. 5 and 6, the coil 14 is configured such that the distance between the coil inner peripheral portion 44 and the inner peripheral side surface 36 of the leg portion 18 of the core member 16 is constant over the entire length of the coil 14. Is formed. This fixed dimension is the same as the minimum dimension d, and corresponds to the thickness dimension of the body portion 28 of the bobbin 26. The inner peripheral portion of the coil 14 is formed in this manner because the two coils 14 are arranged close to each other in the window portion 22 of the reactor core 12 so that the coil 14 is shifted outward as in the outer peripheral portion. This is because the adjacent coils 14 and 14 interfere with each other when the coil shape is adopted. In order to avoid such interference between the coils 14 and 14, it is conceivable to expand the space between the two leg portions 18 and 18 of the core member 16, but this increases the size of the reactor core 12 and reduces the size of the core member. There arises a disadvantage that a new mold for forming is required.

  While the distance between the coil inner peripheral portion 44 and the inner peripheral side surface 36 of the leg portion 18 of the core member 16 is constant over the entire length of the coil at a minimum distance d, the gap between the end surfaces 20 of the leg portions 18 of the core member 16 is constant. The side portion 54 defined by the end surface 20 and the inner peripheral side surface 36 of the leg portion 18 of the core member 16 is subjected to corner processing so that 24 becomes larger in the width direction as it approaches the inner peripheral side surface 36. Specifically, in this corner processing, the side portion 54 of the leg portion 18 is formed as a curved surface having a curvature radius R. This curvature radius R is compared with a curved surface (or a corner dropping plane) having a curvature radius r formed to prevent chipping in the side portion 56 on the outer peripheral side defined by the end surface 20 and the outer peripheral side surface (see FIG. 5). And it is set quite large. Thus, by expanding the gap 24 toward the inner peripheral side surface 36, the magnetic resistance between the leg portions 18 of the core member 16 is increased at this portion.

  In the present embodiment, it has been described that the inner peripheral side portion 54 of the leg portion 18 of the core member 16 is formed as a curved surface defined by the curvature radius R, but the present invention is not limited to this. As long as the gap 24 expands toward the peripheral side surface 36, it may be formed by any shape of curved surface or flat surface. For example, the inner peripheral side portion may be formed by a corner dropping plane 58 such that the cut-off portion in plan view has a right-angled isosceles triangle.

  Then, an effect | action and effect of the reactor 10 which consists of the said structure are demonstrated.

  When the coil 14 of the reactor 10 is energized, the reactor core 12 is excited by energization, and the gap 24 between the inside of the core member 16 and each leg 18 becomes a magnetic path. At this time, as shown in FIG. 4, a leakage magnetic flux M is generated in the vicinity of the gap 24 of the leg portion 18 of the core member 16. The leakage magnetic flux M leaks so as to swell outward from the vicinity of the outer peripheral portion 56 and flows from one core member 16 to the leg portion 18 of the other core member 16.

  When such a leakage magnetic flux M is linked to the coil 14 wound around the eddy current M, an eddy current is generated in the coil 14, thereby generating an eddy current loss. However, in the reactor 10 of the present embodiment, the coil 14 is formed such that the distance between the coil inner peripheral portion 44 and the outer peripheral side surface 38 of the core member 16 is larger than the coil end portions 46 side. Further, this distance is formed so as to be the maximum dimension D in the gap facing region 50 of the coil 14 corresponding to the region where the leakage magnetic flux M swells most. Thereby, the interlinkage area of the leakage magnetic flux M with the coil 14 can be reduced, and eddy current loss can be reduced. As shown in FIG. 6, this effect is not only the distance between the coil inner peripheral portion 44 and the outer peripheral side surface 38 of the leg portion 18 of the core member 16, but also the coil inner peripheral portion 44 and the leg portion of the core member 16. 18, and the distance between the coil inner peripheral portion 44 and the lower side surface 42 of the core member 16 is also more conspicuous by forming the coil 14 to be larger. Become.

  Further, if the distance between the coil inner peripheral portion 44 and the outer peripheral side surface 38 of the core member 16 is increased to the maximum dimension D over the entire length of the coil, the coil end portions 46 and the core member 16 are not passed through the core member 16. Since the magnetic flux passing between the outer peripheral side surface 38 increases, the magnetic flux easily interlinks with the coil 14 and the eddy current loss increases. However, such a problem does not occur in the reactor of this embodiment.

  Furthermore, when the distance between the coil inner peripheral portion 44 and the leg portion 18 of the core member 16 is uniformly increased over the entire length of the coil, the resistance loss increases as the conducting wire 15 constituting the coil 14 becomes longer. In the present embodiment, since the coil 14 is formed so that the distance is larger than the coil end portions 46 in the vicinity of the gap 24 between the core members 16, an increase in resistance loss due to an increase in the coil conductor length is minimized. can do.

  As described above, according to the reactor 10 of the present embodiment, the coil 14 is formed such that the distance between the coil inner peripheral portion 44 and the outer peripheral side surface 38 of the core member is increased in the vicinity of the gap 24 between the core members 16. With a simple configuration, eddy current loss occurring in the coil 14 can be effectively suppressed.

  On the other hand, as shown in FIG. 6, with respect to the inner peripheral portion of the coil 14 located in the window portion 22 of the reactor core 12, in order to avoid interference between the two adjacent coils 14, the coil inner peripheral portion 44 and The distance from the inner peripheral side surface 36 of the leg portion 18 of the core member 16 is formed to be constant with the minimum dimension d over the entire length of the coil. However, the end surface 20 and the inner peripheral side surface 36 of the leg portion 18 of the core member 16 increase so that the gap 24 between the end surfaces 20 of the leg portions 18 of the core member 16 becomes larger as the gap 24 approaches the inner peripheral side surface 36 in the width direction. The prescribed side portion 54 is subjected to corner processing, whereby the gap 24 expands toward the inner peripheral side surface 36, so that the magnetic resistance between the leg portions 18 of the core member 16 is increased at this enlarged portion. . As a result, it is possible to reduce the amount of leakage magnetic flux M flowing out from the vicinity of the side portion 54 that has been subjected to the corner processing, and it is possible to suppress the leakage magnetic flux M from bulging out toward the window portion 22. As a result, the interlinkage area of the leakage magnetic flux M with the coil 14 can also be reduced in the inner peripheral portion of the coil, and eddy current loss can be reduced.

In FIG. 7, the analysis result which verified the effect of the eddy current loss of the coil 14 in the reactor 10 of this embodiment is shown. In the lower diagram in FIG. 7, the right side shows the generation state of eddy current loss (kw / m ³ ) in the half (9) cross-sections of the coil 14 of the present embodiment, and the left side shows the conventional example. The state of occurrence of eddy current loss in the cross section of half (9) conductors constituting the coil (coil in which the distance between the inner peripheral portion of the coil and all side surfaces of the leg portion of the core member is constant at the minimum dimension d) 14b Show. As can be seen from FIG. 7, it can be seen that the eddy current loss indicated by the dot density is considerably reduced in the coil 14 of the present embodiment. As a numerical value, the eddy current loss is about 20 times that of the conventional coil 14b. It was confirmed that it can be reduced by about%.

  Next, the reactor 11 of another embodiment is demonstrated with reference to FIG. Since the reactor 11 of this embodiment has substantially the same configuration as the reactor 10 described above, only the different points will be mainly described here, and the same or similar reference numerals are given to the same or similar configurations. Thus, redundant explanations will be omitted.

  In the reactor 11 of this other embodiment, the inner peripheral portion of the coil 14a located in the window portion 22 of the reactor core 12 is also similar to the other coil portions (that is, the outer peripheral portion of the coil and the upper and lower portions of the coil). The coil 14 a is formed such that the distance between the peripheral portion 44 and the inner peripheral side surface 36 of the leg portion 18 of the core member 16 is larger in the vicinity of the gap 24 than the coil end portions 46. In this case, the side portion 54 of the leg portion 18 of the core member 16 does not need to be subjected to corner processing, and is formed as a small curved surface or a corner dropping plane for preventing chipping, similarly to the side portion 56 on the outer peripheral side. The configuration other than these is the same as the reactor 10 described above.

  In the reactor 11, on the condition that two adjacent coils 14a do not interfere with each other, the distance from the leg portion 18 of the core member 16 is also increased in the vicinity of the gap 24 for the inner peripheral portion of the coil. The coil 14a is formed by shifting the conductive wire 15 of the central portion 48 of the coil 14a away from all the four side surfaces 36, 38, 40, 42 of the leg portion 18 of the core member 16 forming the core member 16. Thereby, also by the reactor 11, the eddy current loss which generate | occur | produces in the coil 14a can be reduced substantially similarly to the said reactor 10. FIG.

  In the above embodiment, the distance to the coil inner peripheral portion 44 is increased in the vicinity of the gap 24 with respect to the three-side side surface 38-42 or the four-side side surface 36-42 of the leg portion 18 of the core member 16 having a rectangular shape. However, the reactor according to the present invention is not limited to this, and the distance to the coil inner peripheral portion 44 is near the gap 24 with respect to at least one of the four side surfaces 36-42. If the coil is formed so as to be larger than the conventional coil 14b, an effect of reducing coil eddy current loss can be expected in comparison with the conventional coil 14b.

  10 reactors, 12 reactor cores, 14 and 14a coils, 15 conductors, 16 core members, 18 legs, 20 end faces, 22 windows, 24 gaps, 26 bobbins, 28 trunks, 30 flanges, 32 receiving holes, 34 centers Position, 36 Inner peripheral side, 38 Outer peripheral side, 40 Upper side, 42 Lower side, 44 Coil inner peripheral part, 46 Coil end part, 48 Coil central part, 50 Gap facing area, 52 Distance change area, 54, 56 sides Part, D maximum dimension, d minimum dimension, M leakage magnetic flux, R, r curvature radius.

Claims (8)

A reactor core comprising two U-shaped or U-shaped core members having two leg portions, the end faces of the leg portions of the core member being arranged opposite to each other with a predetermined gap; A reactor comprising two coils wound around the legs of the core members facing each other through a gap,
The reactor is characterized in that a distance between an inner periphery of the coil and a leg side surface of the core member is formed larger in the vicinity of the gap than at both ends of the coil. The reactor according to claim 1,
The coil portion having a large distance is formed in a length of 3 to 6 times the dimension of the gap, with the center position between the gaps as the axis of symmetry. In the reactor according to claim 1 or 2,
The reactor has a maximum dimension at a position corresponding to the gap, and the maximum dimension is 20% or more larger than a minimum dimension which is the distance at both ends of the coil. The reactor according to claim 3,
The coil portion having a large distance is formed to have a length of 3 to 6 times the dimension of the gap with the center position between the gaps as the axis of symmetry, and the distance change corresponding to 30% or less of the length. The reactor, wherein the distance gradually increases or decreases between a minimum dimension and a maximum dimension in an area, and the distance is set to the maximum dimension outside the distance change area. In the reactor as described in any one of Claims 1-4,
The core member has a rectangular cross-sectional shape and a leg end face shape, and is connected in an annular shape through the gap, and an inner peripheral side surface of the leg portion facing the inner side of the annular shape, an inner peripheral portion of the coil, The coil is formed so that the distance between the coil is constant over the entire length of the coil, while the gap between the outer peripheral side surface of the leg facing the annular outer side and the inner peripheral part of the coil The reactor in which the dimension in the vicinity is formed larger than the fixed dimension at both ends of the coil. The reactor according to claim 5,
The side defined by the end surface of the leg and the inner peripheral side is a corner so that the gap between the end surfaces of the leg of the core member increases as the gap approaches the inner peripheral side in the width direction of the leg. Reactor characterized by being processed. The reactor of Claim 6 WHEREIN: In the said corner process, the said side part is formed as a curved surface, or the said side part is formed as a corner dropping plane, The reactor characterized by the above-mentioned. The reactor according to claim 5,
The dimension in the vicinity of the gap is at least one of the distances between the first and second side surfaces of the leg portion of the core member excluding the inner peripheral side surface and the outer peripheral side surface and the inner peripheral portion of the coil. A reactor characterized in that it is formed larger than the fixed dimension at both ends of the coil.

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