Coil component

Abstract

A coil component (1) has a first core (10), a second core (20), and a base section (30) in which an accommodating recess (32) is formed. The second core (20) includes a flat plate section (22) and legs (24). The legs (24) extend from one end of the flat plate section (22) toward the bottom surface of the accommodating recess (32) in the axial direction of the coil (50). The accommodating recess (32) includes a first space (34) and a second space (36). A winding core section (12) of the first core (10) is accommodated in the first space (34). The second space (36) is a space different from the first space (34). The legs (24) are accommodated in the second space (36). The base section (30) has leg-restricting sections (38). The leg-restricting sections (38) are disposed on the inner side of the legs (24) in the axial direction.

Description

Coil parts

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

[0002] Some coil components have a core divided into multiple pieces, with a coil wound around one portion of the core. Regarding this type of technology, Patent Document 1 below discloses a coil component (100) having an insulating frame (24), two cores (a magnetic core (10) and a second magnetic core (23)), and a coil (54). Specifically, a U-shaped magnetic core (10) is housed in the insulating frame (24), and a coil (54) is wound around the insulating frame (24) and the U-shaped magnetic core (10). An I-shaped second magnetic core (23) is disposed above the U-shaped magnetic core (10). A side of a portion of the I-shaped second magnetic core (23) is surrounded by a wall portion, such as a first wall portion (27) of the insulating frame (24).

[0003] Japanese Patent Application Laid-Open No. 2020-126909

[0004] However, in the coil component (100) described in Patent Document 1, a problem may arise in that the second magnetic core (23) may be misaligned relative to the insulating frame (24). Specifically, the second magnetic core (23) may be misaligned in the axial direction of the coil (54) relative to the insulating frame (24), or may be misaligned rotationally relative to the insulating frame (24) when viewed from above. For example, when the coil component is placed on a mounting board for surface mounting, the position and orientation of the upper magnetic core as viewed from above may be considered to be the position and orientation of the entire coil component, and the coil component may be aligned with the mounting board. In this case, if the second magnetic core (23), which is the upper magnetic core, is misaligned in the axial direction or rotational direction relative to the insulating frame (24), a problem may arise in that the coil component is not positioned in the appropriate position or orientation relative to the mounting board. In addition, if the upper magnetic core (second magnetic core (23)) is arranged with a misalignment in the axial direction or rotation direction relative to the insulating frame (24), the upper magnetic core (second magnetic core (23)) may be arranged with a misalignment relative to the lower magnetic core (magnetic core (10)). In this case, appropriate magnetic properties may not be obtained.

[0005] The present invention has been made in consideration of the above-mentioned problems, and provides a coil component in which the core arranged above is prevented from being misaligned in the axial direction of the coil relative to the base portion, or from being misaligned so as to rotate relative to the base portion when viewed from above.

[0006] The coil component of the present invention has a first core, a base portion having an accommodating recess formed therein and accommodating the first core in the accommodating recess, a terminal portion provided on the base portion, at least one coil connected to the terminal portion and arranged spirally around the winding core portion of the first core and the base portion, and a second core arranged above the first core, wherein the second core includes a flat portion and a leg portion extending from one end of the flat portion toward the bottom surface of the accommodating recess in the axial direction of the coil, the accommodating recess including a first space in which the winding core portion is accommodated and a second space different from the first space in which the leg portion is accommodated, and the base portion has a leg regulating portion arranged inward of the leg in the axial direction.

[0007] In the coil component of the present invention, the second core disposed at the top has legs extending downward, and leg restricting portions (restricting portions) of the base portion are disposed on the inner side of the legs in the axial direction. As a result, when the second core tends to shift axially or rotate relative to the base portion, the restricting portions restrict the movement of the second core, thereby suppressing the shift of the second core.

[0008] According to the coil component of the present invention, the restricting portion prevents the second core from being misaligned with respect to the base portion, thereby providing a coil component in which the second core disposed above is prevented from being misaligned with respect to the base portion in the axial direction of the coil or from being misaligned so as to rotate with respect to the base portion when viewed from above.

[0009] The above-mentioned objects, as well as other objects, features and advantages, will become more apparent from the preferred embodiments described below and the accompanying drawings.

[0010] 7A is a perspective view showing an example of a coil component according to a first embodiment of the present invention; FIG. 7B is an exploded perspective view of the coil component according to the first embodiment; FIG. 7C is a left side view of the coil component according to the first embodiment; FIG. 7D is a top view of the coil component according to the first embodiment; FIG. 7E is a front view of the coil component according to the first embodiment; FIG. 7F is a bottom view of the coil component according to the first embodiment; FIG. 7G is a cross-sectional view of the front end of the coil component according to the second embodiment of the present invention; FIG. 7H is a cross-sectional view of the front end of the coil component according to the second embodiment of the present invention; FIG. 7H is a cross-sectional view of the front end of the coil component according to the second embodiment of the present invention; FIG. 7H is a cross-sectional view of the front end of the coil component according to the second embodiment of the present invention; FIG. 7H is a cross-sectional view of the front end of the coil component according to the second embodiment of the present invention; FIG. 7G is a cross-sectional view of the front end of the coil component according to the second embodiment of the present invention; 11(a) is a cross-sectional view of the coil component according to the second embodiment taken along the dashed line in Fig. 3, as viewed in a direction corresponding to the direction of the arrow VIII-VIII in Fig. 3. Fig. 11(b) is a cross-sectional view of another example of the coil component according to the third embodiment.

[0011] The various components of the coil component of the present invention do not need to be independent entities, and it is acceptable for multiple components to be formed as a single member, for one component to be formed from multiple members, for one component to be part of another component, or for part of one component to overlap with part of another component, etc.

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing, corresponding components are designated by the same reference numerals, and redundant descriptions will be omitted where appropriate. In this embodiment, the front-rear, left-right, top-bottom directions will be defined as illustrated. However, these definitions are provided for convenience in order to easily explain the relative relationships between components, and do not limit the directions during manufacture or use of a product embodying the present invention. In this embodiment, the top-bottom direction refers to a direction perpendicular to the surface of a mounting board when a coil component is mounted on the mounting board. When a coil component is mounted on a horizontal mounting board, the top-bottom direction coincides with the vertical direction. However, when a coil component is mounted on an inclined mounting board, the top-bottom direction is inclined relative to the vertical direction. The front-rear and left-right directions may also be referred to as lateral directions. In this embodiment, the front-rear direction coincides with the axial direction of the coil. Furthermore, the left-right direction may also be referred to as the width direction of the coil component, and the top-bottom direction may also be referred to as the height direction of the coil component or a member of the coil component. Furthermore, the term "plane" as used herein refers to a shape that is physically formed with a flat surface as the target, and naturally does not necessarily have to be a perfect geometric plane.

[0013] First Embodiment (Coil Component) Fig. 1 is a perspective view showing an example of a coil component 1 according to a first embodiment of the present invention. Fig. 2 is an exploded perspective view of the coil component 1.

[0014] First, an overview of the coil component 1 of this embodiment will be described. As shown in FIG. 2 , the coil component 1 of this embodiment includes a first core 10, a base portion 30, a terminal portion 40, at least one coil 50, and a second core 20. An accommodating recess 32 is formed in the base portion 30. The base portion 30 accommodates the first core 10 in the accommodating recess 32. The terminal portion 40 is provided on the base portion 30. The coil 50 is connected to the terminal portion 40. The coil 50 is arranged in a spiral shape around the winding core portion 12 and the base portion 30 of the first core 10. The second core 20 is arranged above the first core 10. The second core 20 includes a flat portion 22 and leg portions 24. The leg portions 24 extend from one end (core end portion 14) of the flat portion 22 toward the bottom surface of the accommodating recess 32 in the axial direction of the coil 50. The accommodating recess 32 includes a first space 34 and a second space 36. The first space 34 accommodates the winding core portion 12. The second space 36 is a space different from the first space 34. The second space 36 accommodates the leg portions 24. The base portion 30 has a leg restricting portion (restricting portion 38). The restricting portion 38 is arranged on the inner side of the leg portions 24 in the axial direction. In the coil component 1 of the present invention, the second core 20 arranged on the upper side has the leg portions 24 extending downward, and the restricting portion of the base portion is arranged on the inner side of the leg portions 24 in the axial direction. As a result, when the second core 20 tends to shift axially or rotate relative to the base portion 30, the restricting portion 38 restricts the movement of the second core, thereby suppressing the shift of the second core. This makes it possible to provide a coil component 1 in which the second core 20 arranged on the upper side is prevented from being shifted axially of the coil 50 relative to the base portion 30 or from being shifted rotationally relative to the base portion 30 when viewed from above. Note that a misalignment of the second core 20 relative to the base portion 30 in the axial direction of the coil 50 is sometimes referred to as a lateral misalignment, and a misalignment of the second core 20 relative to the base portion 30 in a rotating manner as viewed from above is sometimes referred to as a rotational misalignment.

[0015] Next, the coil component 1 of this embodiment will be described in detail. The coil component 1 is an electronic component having a coil 50. An electronic component is a component that can constitute part of an electronic circuit. Examples of the coil component 1 include a transformer, an antenna, and an inductor. The coil component 1 of this embodiment is mounted on a mounting substrate (not shown) so that the mounting surface of a terminal portion 40 (described later) is in contact with the mounting surface.

[0016] The coil 50 is a component formed by helically arranging a conductive material. The coil 50 in this embodiment is a coil formed by helically arranging a coil wire having a circular cross section. The coil 50 may be formed by a coil wire having a flat cross section (e.g., rectangular or elliptical). The manufacturing method of the coil 50 is not limited, and the coil 50 may be any type of helically shaped conductive material. In this embodiment, the coil 50 is formed by winding a coil wire around the first core 10 and the base portion 30. The coil wire of the coil 50 may be in pressure contact with or abut against the upper surface of the first core 10, or the winding core side portion 35 or bottom surface portion 30a of the base portion 30. Alternatively, the coil wire may be arranged so as to bite into the upper surface of the first core 10, or the winding core side portion 35 or bottom surface portion 30a of the base portion 30. Alternatively, the coil wire may be spaced apart from the upper surface of the first core 10, or the winding core side portion 35 or bottom surface portion 30a of the base portion 30. Alternatively, the coil 50 may be formed in advance by arranging a conductive material in a spiral shape so that the core portion is hollow. In this case, after the coil is formed, the first core 10 and the base portion 30 may be inserted into the hollow portion of the coil. The inner surface of the winding portion 53 (the peripheral surface of the flat wire) and the first core 10 or the base portion 30 may be spaced apart or in contact with each other.

[0017] The coil component 1 may have one or more coils 50. In this embodiment, the coil component 1 has two coils 50 (a first coil 51 and a second coil 52). The axial direction of the first coil 51 and the axial direction of the second coil 52 are both in the front-to-rear direction, and the axial directions of the first coil 51 and the second coil 52 are arranged parallel to each other. More specifically, the winding axis of the first coil 51 is arranged on the same line as the winding axis of the second coil 52. The coil 50 has a winding portion 53 formed by winding a coil wire. The coil 50 has lead-out portions 54, which are both ends of the coil wire and are parts of the coil wire drawn out from the winding portion 53. In the coil 50 of this embodiment, both ends of the coil wire are drawn out, and each of the both ends is connected to the terminal portion 40. As shown in FIG. 3 , the lead-out portion 54 extends toward the terminal portion 40 (the connection portion 42). 6, the lead-out portion 54 is wired along the lower surface of the base portion 30 and extends from the winding portion 53 to the connecting portion 42. The lead-out portion 54 and the connecting portion 42 are electrically connected.

[0018] The terminal portion 40 is an electrode member electrically connected to the coil 50. The terminal portion 40 serves as an input electrode or an output electrode of the coil component 1. The terminal portion 40 is formed of a conductive material such as metal. As shown in FIG. 6 , two terminal portions 40 are provided on each of two side wall portions 37 (described later). The terminal portion 40 includes a connecting portion 42, an intermediate portion 44, and a mounting portion 46. The connecting portion 42 is a portion to which an end of the lead portion 54 is connected. The coil component 1 of this embodiment is manufactured by intertwining the end of the lead portion 54 with the connecting portion 42 during the manufacturing process and welding the connecting portion 42 and the end of the lead portion 54. The connecting portion 42 and the lead portion 54 may be joined by soldering or the like. The mounting portion 46 is a portion of the terminal portion 40 that is grounded to a substrate (not shown) when the coil component 1 is mounted. Specifically, the mounting portion 46 includes a mounting surface facing downward, which is in surface contact with the substrate. The mounting portion 46 and the board are joined by soldering or the like. The intermediate portion 44 is a portion sandwiched between the connecting portion 42 and the mounting portion 46. In this embodiment, the intermediate portion 44 is embedded in the base portion 30. The connecting portion 42 and the mounting portion 46 are exposed from the base portion 30.

[0019] The cores (first core 10 and second core 20) are members made of a magnetic material. In this embodiment, the first core 10 is a so-called I-core, and the second core 20 is a so-called U-core. The first core 10 and the second core 20 are combined to form a closed magnetic circuit. The shapes of the first core 10 and the second core 20 are not limited to those described above. For example, the first core 10 and the second core 20 may each be L-shaped and combined to form a closed magnetic circuit. Alternatively, the first core 10 and the second core 20 may both be U-cores. An adhesive (not shown) may be disposed between the first core 10 and the second core 20. Specifically, the upper surface 10a of a core end portion 14 (described later) may be bonded to the lower surface 24c of the leg portion 24 via an adhesive. Furthermore, a sheet (a non-magnetic spacer sheet) for forming a gap may be disposed between the first core 10 and the second core 20. Two spacer sheets may be disposed between the front core end 14 and the lower surfaces 24c of the leg portions 24, and between the rear core end (core end 14) and the lower surfaces 24c of the leg portions 24, respectively. Alternatively, one spacer sheet may be disposed across both ends (core ends 14, 14) of the first core 10. In other words, one spacer sheet may be disposed over substantially the entire upper surface of the first core 10, and the spacer sheet may be disposed between the front core end 14 and the leg portions 24 and between the rear core end 14 and the leg portions 24.

[0020] The first core 10 is a core disposed below the second core 20. In this embodiment, the first core 10 is a flat plate extending laterally. A coil 50 is wound around a winding core portion 12, which corresponds to the center of the first core 10 in the front-rear direction. Here, "the coil 50 is wound around a predetermined member (such as the first core 10 or the base portion 30)" means that the coil 50 is disposed around the predetermined member. Any other member may or may not be disposed between the predetermined member and the coil 50. In other words, "the coil 50 is wound around a predetermined member" includes the coil 50 being indirectly or directly wound around the predetermined member. In this embodiment, it can be said that the coil 50 is indirectly wound around the first core 10 via the base portion 30. Both ends of the first core 10 in the front-rear direction are core end portions 14. The second core 20 is a core disposed above the first core 10. The second core 20 may be placed directly on the first core 10 in contact with the first core 10, or may be disposed above the first core 10 and spaced apart from the upper surface of the first core 10. In this embodiment, the lower surfaces of leg portions 24 of the second core 20, which will be described later, contact the core end portion 14 of the first core 10, and the second core 20 is placed directly on the first core 10. The second core 20 has a flat plate portion 22 and one or more leg portions 24. Specifically, the second core 20 has two leg portions 24 adjacent to each end of the flat plate portion 22 in the front-to-rear direction. The flat plate portion 22 is a part of the second core 20 that has a flat plate shape and extends laterally. The leg portions 24 are parts of the second core 20 that extend in a direction intersecting the main surface of the flat plate portion 22. The leg portions 24 are formed to protrude downward from the flat plate portion 22. The leg portions 24 may extend in a direction perpendicular to the main surface of the flat plate portion 22, or in a diagonal direction.

[0021] The base portion 30 is a member that holds the first core 10 and the second core 20. The base portion 30 is formed of an insulating material such as resin. The accommodating recess 32 in the base portion 30 is a space in which the first core 10 or the second core 20 is disposed. In this embodiment, the accommodating recess 32 is formed by recessing the base portion 30 downward. The accommodating recess 32 accommodates the first core 10. "Accommodating the first core 10 in the accommodating recess 32" means that at least a portion of the first core 10 is disposed in the accommodating recess 32. In this embodiment, the entire first core 10 is disposed in the accommodating recess 32. More specifically, the first core 10 is disposed across the first space 34 and the second space 36. The first space 34 is a space in which the winding core portion 12 of the first core 10 is disposed. Specifically, the first space 34 is defined by the bottom surface portion 30a and the winding core side portion 35. In this embodiment, the upper end of the first space 34 terminates at the imaginary upper surface of the base portion 30 (an imaginary surface that includes the upper end of a side wall portion 37, which will be described later). The front-to-rear boundary of the first space 34 will be described later. The core side portion 35 is a part of the base portion 30 that is arranged to stand up from the bottom surface portion 30a. In this embodiment, the two core side portions 35 are arranged spaced apart in the left-right direction. The core portion 12 is arranged between the two core side portions 35.

[0022] The second space 36 being a space different from the first space 34 means that the second space 36 does not overlap the first space 34. The second space 36 is a space in which at least a portion of the leg portion 24 of the second core 20 is disposed. In this embodiment, the accommodating recess 32 includes two second spaces 36 that accommodate each of a pair of leg portions 24 spaced apart in the front-rear direction. The two second spaces 36 are disposed on either side of the first space 34 in the front-rear direction. The second space 36 is defined by a bottom surface 30a and a side wall portion 37. The bottom surface 30a is a portion that includes the lower surface of the base portion 30. The side wall portion 37 is a portion of a wall of the base portion 30 that rises from the bottom surface 30a and is U-shaped in plan view, surrounding the sides of the leg portion 24. Specifically, the side wall portions 37 are disposed outward of the leg portion 24 in the front-rear direction and on both sides of the leg portion 24 in the left-right direction. Here, the outer side in the front-rear direction refers to the peripheral edge of the base portion 30 in the front-rear direction (the peripheral edge of the base portion 30 when viewed from above). The inner side in the front-rear direction refers to the center of the base portion 30 in the front-rear direction (the center of the base portion 30 when viewed from above). In this embodiment, the upper end of the second space 36 is a virtual plane (a virtual plane extending laterally) that includes the upper end of the side wall portion 37. In this embodiment, as shown in FIG. 5 , a portion of the upper surface of the second core 20 (particularly the flat plate portion 22) is located above the upper end of the side wall portion 37. That is, a portion of the upper surface of the flat plate portion 22 is located outside the envelope volume of the base portion 30. In other words, a portion of the lower surface of the flat plate portion 22 of the second core 20 is located within the accommodating recess 32 (particularly the second space 36 or the first space 34), and a portion of the upper surface of the flat plate portion 22 is located outside the accommodating recess 32. In the present embodiment, in addition to the leg portions 24 of the second core 20, the core end portion 14 of the first core 10 is also disposed in the second space 36. As in a third embodiment described below, the core end portion 14 does not have to be disposed in the second space 36. As shown in FIG. 7A , the accommodating recess 32 includes a space sandwiched between the second side surfaces 38 d of a pair of restricting portions 38 described below (a space where the boundary portion between the core end portion 14 and the winding core portion 12 of the first core 10 is disposed; this space is referred to as a boundary space). This boundary space may belong to the first space 34 or the second space 36.

[0023] As shown in FIG. 7A , the restricting portion 38 is a part of the base portion 30 and is a part that can restrict the movement of the leg portion 24. Here, "the restricting portion 38 can restrict the movement of the leg portion 24" means that the restricting portion 38 can restrict the movement of the leg portion 24 relative to the base portion 30 during the manufacturing process of the coil component 1 or in the finished product. "The restricting portion 38 can restrict the movement of the leg portion 24" includes not only that the leg portion 24 is restricted from moving in a certain direction relative to the base portion 30 in the finished product of the coil component 1, but also that the leg portion 24 can abut against the restricting portion 38 during the manufacturing process of the coil component 1 and that the restricting portion 38 can restrict the movement of the leg portion 24 in a certain direction relative to the base portion 30. The restricting portion 38 restricts the movement of the leg portion 24 by being disposed adjacent to the leg portion 24. Here, "the restricting portion 38 is adjacent to the leg portion 24" means that the distance between the restricting portion 38 and the leg 24 is equal to or less than a predetermined distance. Specifically, the distance (distance D3) between the restricting portion 38 and the leg portion 24 is preferably smaller than the distance (distance D4 or distance D5) between the side wall portion 37 and the leg portion 24. More specifically, the distance between the restricting portion 38 and the leg portion 24 in the front-rear direction is preferably smaller than the distance (distance D4) between the side wall portion 37 and the leg portion 24 in the front-rear direction or the distance (distance D5) between the side wall portion 37 and the leg portion 24 in the left-right direction. In this embodiment, the restricting portion 38 is an inner wall portion extending in the left-right direction. The inner wall portion can be said to define each of the first space 34 and the second space 36. The inner wall portion is arranged to rise from the bottom surface portion 30a of the base portion 30 (see FIG. 2). Furthermore, the inner wall portion is formed integrally with the side wall portion 37. The shape of the restricting portion 38 is not limited to the inner wall portion as in this embodiment. For example, the restricting portion 38 may be a columnar portion that protrudes upward from the bottom surface portion 30a, and the columnar portion may be formed at a distance from the side wall portion 37. Alternatively, the restricting portion 38 may be a protruding portion that protrudes inward in the left-right direction from the side wall portion 37. The protruding portion may be spaced apart from the bottom surface portion 30a (see FIG. 2 ) of the base portion 30. In this embodiment, the dimension of the base portion 30 in the front-rear direction is larger than the dimension of the base portion 30 in the left-right direction, but the dimension of the base portion 30 in the left-right direction is greater than or equal to a predetermined size relative to the dimension of the base portion 30 in the front-rear direction.In other words, the dimension in the left-right direction of the portion of the base portion 30 that constitutes the first space 34 is greater than the dimension in the front-rear direction. The restricting portion 38 is disposed near the center of the base portion 30 in the front-rear direction. More specifically, the distance in the left-right direction (distance D8) between the center of the base portion 30 in the left-right direction and the restricting portion 38 (second side surface 38d) is greater than the distance in the front-rear direction (distance D9) between the center of the base portion 30 in the front-rear direction and the restricting portion 38 (the center in the front-rear direction of the restricting portion 38 or the main surface of the restricting portion 38 facing the winding portion 53). Furthermore, the distance between the second side surfaces 38d of a pair of restricting portions 38 aligned in the left-right direction is greater than the distance in the front-rear direction between the first leg portion 24f and the second leg portion 24g (the distance between the inner surfaces 24d of the pair of legs 24). Due to this dimensional relationship, the inner surfaces 24d of the legs 24 are likely to come into contact with the restricting portion 38 (particularly the second side surface 38d), as described below.

[0024] In this embodiment, the restricting portion 38 also serves as a winding frame portion that assists in winding the coil 50. That is, the restricting portion 38 is disposed on the outer side of the coil 50 (winding portion 53) in the axial direction. More specifically, the restricting portion 38 is disposed between the coil (the coil wire in the winding portion 53) and the leg portion 24 in the axial direction.

[0025] As shown in FIG. 7A , the base portion 30 has two pairs of restricting portions 38 (first restricting portion 38 a, second restricting portion 38 b). The two pairs of restricting portions 38 are arranged on both sides of the first core 10 in the width direction of the base portion 30. The first restricting portion 38 a and the second restricting portion 38 b are adjacent to both ends of one leg portion 24 in the left-right direction, respectively. This more effectively suppresses misalignment of the leg portion 24. Note that in this embodiment, the second core 20 has two legs 24. Therefore, in this embodiment, restricting portions 38 are arranged adjacent to both ends of each leg portion 24. That is, in this embodiment, the base portion 30 has four restricting portions 38.

[0026] As shown in FIG. 7B , the leg portion 24 has an inner surface 24d facing the restricting portion 38. The orthogonal direction indicated by the dashed-dotted line II in FIG. 7B may be inclined with respect to the axial direction (the direction indicated by the dashed-dotted line I in FIG. 7B ). That is, the second core 20 may be rotated with respect to the axial direction when viewed from above. The orthogonal direction is a direction perpendicular to the inner surface. In this embodiment, the orthogonal direction can also be referred to as the direction in which the pair of legs 24, 24 are aligned. By rotating the second core 20 in a predetermined direction, the manufacturing error due to the angular difference between the linear direction and the axial direction can be reduced. That is, the manufacturing error in the magnetic characteristics caused by the misalignment of the second core 20 with respect to the first core 10 can be reduced. In this embodiment, the inner surface 24d is a flat surface, but it may also be a slightly curved surface. If the inner surface 24d is a curved surface, the orthogonal direction may be a direction perpendicular to a tangent line near the center of the inner surface 24d in the left-right direction when viewed from above. In addition, in this embodiment, the inner surface 24d faces the main surface (first side surface 38c, described later) of the restricting portion 38, which is an inner wall portion. The inner surface 24d and the first side surface 38c may be arranged parallel to each other, or the inner surface 24d may be arranged at a position intersecting the first side surface 38c. In this embodiment, the second core 20 is arranged rotated counterclockwise with respect to the axial direction. However, the second core 20 may be arranged rotated clockwise with respect to the axial direction. The angle (rotation angle) between the orthogonal direction and the axial direction is preferably greater than 0 degrees and less than 10 degrees. More preferably, the rotation angle is greater than 0 degrees and less than 5 degrees. This reduces the occurrence of positional or orientation deviations when the coil component 1 is placed on a mounting board and surface-mounted. In this embodiment, the dimension (width dimension) of the leg portion 24 in the left-right direction is greater than the dimension (width dimension) of the core end portion 14 in the left-right direction. This prevents a significant reduction in the area of ​​the region where the second core 20 (lower surface 24c of the leg portion 24 (see FIG. 9(b))) and the first core 10 (upper surface 10a of the core end portion 14 (see FIG. 9(b))) overlap in the vertical direction, even when the second core 20 is positioned rotated in the axial direction. This prevents a large magnetic flux leakage from occurring.In the present embodiment, of the pair of restricting portions 38 spaced apart in the left-right direction, the distance in the front-rear direction between the first restricting portion 38a and the inner surface 24d is smaller than the distance in the front-rear direction between the second restricting portion 38b and the inner surface 24d. The distance in the front-rear direction between the first restricting portion 38a and the inner surface 24d also includes a case where the first restricting portion 38a and the inner surface 24d abut against each other and are zero. Instead of the orthogonal direction being inclined with respect to the axial direction as shown in FIG. 7(b), the orthogonal direction may be parallel to the axial direction as shown in FIG. 7(a).

[0027] As shown in FIG. 7B , the leg 24 contacts the first restricting portion 38a of the pair of restricting portions 38. Meanwhile, the leg 24 is spaced from the second restricting portion 38b of the pair of restricting portions 38. Specifically, the inner surface 24d of the leg 24 contacts the first side surface 38c of the first restricting portion 38a. In a second embodiment described later, the first side surface 38c shown in FIG. 10 may contact the inner surface 24d, or the second side surface 38d may contact the side surface of the step portion 24e (particularly the surface facing outward in the left-right direction). By keeping the leg 24 in contact with the restricting portion 38, production errors due to misalignment of the second core 20 relative to the first core 10 can be more effectively reduced. In this embodiment, the outward-facing side surface of the leg 24 in the front-rear direction abuts the side wall portion 37. The leg portions 24 abut against the side wall portion 37 and the restricting portion 38 at two locations, thereby favorably fixing the position of the second core 20 in the base portion 30. In the present embodiment, an example is shown in which each of the pair of legs 24 abuts against the side wall portion 37 and the restricting portion 38 at two locations, but instead, one leg portion 24 may abut against the side wall portion 37 and be spaced apart from the restricting portion 38, and the other leg portion 24 may abut against the restricting portion 38 and be spaced apart from the side wall portion 37.

[0028] As shown in FIG. 8 , the first side surface 38c is the side surface of the restricting portion 38 facing the leg portion 24. The first side surface 38c is also the main surface of the restricting portion 38, which is an inner wall portion. In this embodiment, the first side surface 38c is inclined obliquely with respect to the mounting direction (vertical direction). The mounting direction is the direction in which the second core 20 is mounted on the first core 10. In other words, the mounting direction is also a direction perpendicular to the upper surface of the first core 10 or the lower surface (lower surface 24c of the leg portion 24) of the second core 20. The distance D1 between the restricting portion 38 and the lower end 24a of the leg portion 24 is smaller than the distance D2 between the restricting portion 38 and the upper end 24b of the leg 24. With the above configuration, the second space 36 is wide at the opening and narrows near the bottom surface 30a. As a result, the second core 20 can be easily positioned in the second space 36 while still being able to be positioned at a desired position on the first core 10. For convenience of illustration, the first side surface 38c in FIG. 8 is shown as being greatly inclined.

[0029] The first side surface 38c being inclined in the up-down direction means, more specifically, that the first side surface 38c is inclined outward in the front-to-rear direction toward the bottom surface portion 30a (i.e., downward). As a result, the second space 36 is wider at the top and narrower at the bottom. In particular, the dimensions of the second space 36 in the front-to-rear direction increase toward the top and decrease toward the bottom. In this embodiment, the first side surface 38c is an inclined flat surface, but this is not limited thereto. The first side surface 38c may also be a curved surface. For example, the first side surface 38c may be a convex surface that protrudes toward the leg portion, or a recessed concave surface. The distance (distance D2) between the upper end portion 24b of the leg portion 24 and the first side surface 38c is the distance between the surface of the upper end portion 24b in the front-to-rear direction (an upper portion of the inner surface 24d) and an upper portion (near the top end) of the first side surface 38c. The distance (distance D1) between the lower end 24a of the leg 24 and the first side surface 38c is the distance between the surface of the lower end 24a in the front-to-back direction (a lower part of the inner surface 24d) and a lower part of the first side surface 38c (near the lower end).

[0030] As shown in FIG. 9( a), the bottom surface portion 30a has a pair of two elevated portions 31. As shown in FIG. 9( b), the pair of elevated portions 31 protrude upward from the surface (bottom surface 30b) of the bottom surface portion 30a on which the first core 10 is placed. The pair of elevated portions 31 are disposed on either side of the first core 10 in the width direction of the base portion 30. The pair of elevated portions 31 effectively suppress misalignment of the first core 10. In the present embodiment, as shown in FIG. 2, the side surface of the elevated portion 31 (the surface facing inward in the left-right direction) is continuous with the side surface of the core side portion 35 (the surface facing inward in the left-right direction). The side surface of the elevated portion 31 is also continuous with the second side surface 38d of the restricting portion 38 (see FIG. 7( a)). That is, the side surface of the plateau portion 31, the side surface of the winding core side portion 35, and the second side surface 38d of the restricting portion 38 are arranged on the same plane (a surface extending in the axial direction). The first core 10 is positioned in the axial direction by a surface formed by the side surface of the plateau portion 31, the side surface of the winding core side portion 35, and the second side surface 38d of the restricting portion 38. As shown in FIG. 9( b ), in this embodiment, the side surface of the first core 10 and each plateau portion 31 (their side surfaces) are spaced apart. That is, a gap is provided between the side surface of the first core 10 and the side surface of the plateau portion 31. An adhesive or the like may be poured into the gap. Alternatively, the side surface of the first core 10 and the side surface of at least one plateau portion 31 may abut against each other.

[0031] As shown in FIG. 9B , the lower surfaces 24c of the legs 24 and the upper surface 10a of the core end portion 14 of the first core 10 are disposed opposite to each other. More specifically, the lower surfaces 24c of the legs 24 are in surface contact with the upper surface 10a of the first core 10. This reduces leakage magnetic flux between the lower surface end portions 24h of the second core 20 and the upper surface 10a of the first core 10, compared to when the lower surface end portions 24h of the legs 24 of the second core 20 are not in contact with the upper surface 10a of the first core 10. In this embodiment, the legs 24 are formed wider than the core end portion 14. Specifically, both end portions (lower surface end portions 24h) of the lower surfaces 24c of the legs 24 in the width direction (left-right direction) of the base portion 30 are disposed outward in the width direction from both end portions (upper surface end portions 10a1) of the upper surface 10a of the core end portion 14 in the width direction (extending to the outside). In other words, the side surfaces of the legs 24 (side surfaces facing outward in the left-right direction) are positioned further outward in the left-right direction than the side surfaces of the core end portions 14 (side surfaces facing outward in the left-right direction). Both ends (lower surface end portions 24h) of the lower surfaces 24c of the legs 24 face and are spaced apart from the upper surfaces of the plateau portions 31. That is, there is a gap between the lower surface end portions 24h and the upper surfaces of the plateau portions 31. The separation between the plateau portions 31 and the second core 20 ensures more reliable contact between the first core 10 and the second core 20, thereby reducing leakage magnetic flux between the first core 10 and the second core 20. Furthermore, the plateau portions 31 made of resin generally have a larger thermal expansion coefficient than the first core 10 made of a magnetic material such as ferrite. In contrast, by providing a gap in the vertical direction between the plateau portion 31 and the second core 20, even if heat is generated during use of the coil component 1 and the plateau portion 31 unexpectedly expands and deforms significantly upward, the plateau portion 31 is prevented from contacting the second core 20 and pushing up the second core 20 so that the first core 10 and the second core 20 are separated.

[0032] Second Embodiment Fig. 10 is a cross-sectional view showing an example of a coil component 1 according to this embodiment. First, an overview of the coil component 1 of this embodiment will be described.

[0033] The coil component 1 of this embodiment has the following features, similar to the coil component 1 of the first embodiment. The base portion 30 has leg portion restricting portions (restricting portions 38). The restricting portions 38 are arranged axially inward of the legs 24. The distance between the restricting portions 38 and the lower ends 24a of the legs 24 is smaller than the distance between the restricting portions 38 and the upper ends 24b of the legs 24 (see FIG. 8 in the first embodiment). The bottom surface portion 30a has a pair of plateau portions 31, and the pair of plateau portions 31 is arranged across the first core 10 in the width direction of the base portion 30 (see FIGS. 9(a) and 9(b) in the first embodiment). Both end portions (lower surface end portions 24h) of the lower surface 24c face and are spaced apart from the upper surfaces of the plateau portions 31 (see FIGS. 9(a) and 9(b) in the first embodiment).

[0034] The leg portions 24 of this embodiment differ from the first embodiment in that they have protrusions (step portions 24e). The step portions 24e protrude inward in the orthogonal direction (front-rear direction in FIG. 10 ) from the inner surfaces 24d of the leg portions 24. The step portions 24e are sandwiched between a pair of restricting portions 38. By having the step portions 24e in the leg portions 24, the cross section of the magnetic path formed by the second core 20 and the first core 10 can be increased by the cross-sectional area of ​​the step portions 24e without increasing the length of the magnetic path. Furthermore, by having the step portions 24e sandwiched between the restricting portions 38 in the width direction, lateral or rotational deviation of the second core 20 can be more effectively suppressed.

[0035] Next, the coil component 1 of this embodiment will be described in detail. The coil component 1 of this embodiment differs from the first embodiment in the shape of the leg of the second core. In this embodiment, the step portion 24e extends from the upper end to the lower end of the leg 24. That is, the step portion 24e extends in the vertical direction (the depth direction of the paper in FIG. 10 ). Alternatively, the step portion 24e may be formed only on a portion of the leg 24 in the vertical direction. For example, the step portion 24e may not be formed near the upper end or the lower end of the leg 24. The width dimension (left-right dimension) of the step portion 24e of this embodiment is equal to the width dimension of the first core 10. Therefore, substantially the entire lower surface of the step portion 24e contacts the upper surface 10a of the first core 10 (see FIG. 9B ). As in the first embodiment, a pair of restricting portions 38 (first restricting portion 38a, second restricting portion 38b) arranged to be spaced apart in the left-right direction of this embodiment have second side surfaces 38d that face the space between the pair of restricting portions 38. More specifically, the step portion 24e being sandwiched between the pair of restricting portions 38 means that the step portion 24e is sandwiched between the second side surfaces 38d of the pair of restricting portions 38.

[0036] In this embodiment, as shown in FIG. 10 , the orthogonal direction of the second core 20 coincides with the front-rear direction. Instead of the aspect shown in FIG. 10 , the orthogonal direction of the second core 20 may be inclined with respect to the axial direction, as shown in FIG. 7B of the first embodiment. In this case, the distance between the second side surface 38d and the step portion 24e of one restricting portion 38 (first restricting portion 38a) is preferably greater than the distance between the second side surface 38d and the step portion 24e of the other restricting portion 38 (second restricting portion 38b). Here, the distance between the second side surface 38d of the restricting portion 38 and the step portion 24e refers to, for example, the distance in the left-right direction between the second side surface 38d of the restricting portion 38 and the side surface of the step portion 24e (the side surface facing outward in the left-right direction). Preferably, the leg 24 is in contact with the first restricting portion 38a of the pair of restricting portions 38 and is spaced apart from the second restricting portion 38b of the pair of restricting portions 38. The second side surface 38d of the first restricting portion 38a may be in contact with the side surface of the step portion 24e of the leg 24 (the side surface facing outward in the left-right direction), or the first side surface 38c of the first restricting portion 38a may be in contact with the inner surface 24d of the leg 24.

[0037] 11(a) and 11(b) are longitudinal cross-sectional views showing an example of a coil component 1 according to this embodiment. First, an overview of the coil component 1 according to this embodiment will be described.

[0038] The coil component 1 of this embodiment has the following features, similar to the coil component 1 of the first embodiment. The base portion 30 has a leg portion restricting portion (restricting portion 38). The restricting portion 38 is disposed on the inner side of the leg portion 24 in the axial direction. The orthogonal direction of the second core 20 may be inclined with respect to the axial direction (see FIG. 7(b) in the first embodiment). The leg portion 24 is in contact with a first restricting portion 38a of the pair of restricting portions 38, and the leg portion 24 is spaced apart from a second restricting portion 38b of the pair of restricting portions 38 (see FIG. 7(b) in the first embodiment). The distance between the restricting portion 38 and the lower end portion 24a of the leg portion 24 is smaller than the distance between the restricting portion 38 and the upper end portion 24b of the leg portion 24 (see FIG. 8 in the first embodiment).

[0039] As shown in Fig. 11A, the second core 20 of this embodiment is similar to the first embodiment in that it has legs 24 at both axial ends. On the other hand, the first core 10 of this embodiment differs from the first embodiment in that it is disposed between the two legs 24 in the axial direction. With the above configuration, the axial end of the first core 10 and the legs 24 of the second core 20 can be spaced apart from each other in the axial direction. This makes it possible to provide a gap between the first core 10 and the second core 20 without using a non-magnetic spacer sheet, compared to the first or second embodiment in which the second core 20 is mounted on the core end 14 of the first core 10.

[0040] Next, the coil component 1 of this embodiment will be described in detail. The coil component 1 of this embodiment differs from the first and second embodiments in the shapes of the first and second cores.

[0041] 11(a), in this embodiment, the second core 20 is placed on the bottom surface portion 30a. As in the first embodiment, the leg portions 24 are arranged in the second space 36 of the accommodating recess 32. On the other hand, in this embodiment, the first core 10 is arranged only in the first space 34 and not in the second space 36. In other words, the first core 10 is not arranged below the leg portions 24. The entire first core 10 forms the winding core portion 12, and almost the entire first core 10 is arranged on the inner diameter side of the coil 50. The first core 10 is arranged to be sandwiched in the front-rear direction between the inner surfaces 24d of a pair of leg portions 24 arranged spaced apart in the front-rear direction.

[0042] The distance between the first leg 24f and the first core 10 (distance D6 in FIG. 11A ) may be greater than the distance between the second leg 24g and the first core 10 (distance D7 in FIG. 11A ). By positioning the first core 10 so that it is closer to one of the legs 24 of the second core 20, it is possible to effectively reduce manufacturing errors in the position of the first core 10 relative to the position of the second core 20. In other words, by positioning the first core 10 so that it is biased toward one of the legs 24, particularly by positioning it so that it abuts against the one leg 24, it is possible to position the first core 10 in the front-to-rear direction, thereby reducing manufacturing errors. Note that the total distance between the first core 10 and each leg 24 (the sum of distances D6 and D7) remains constant whether the first core 10 is positioned in the center of the pair of legs 24, 24 in the front-to-rear direction or whether the first core 10 is positioned forward or rearward of the center of the pair of legs 24, 24 in the front-to-rear direction. That is, by separating the first core 10 and the second core 20 (legs 24) in the front-rear direction to form a gap, it is possible to reduce errors in magnetic characteristics due to the position of the first core 10. Here, the distance between the legs 24 and the first core 10 is, more specifically, the distance in the front-rear direction between the inner surface 24d of the legs 24 and the side surface of the first core 10 facing outward in the front-rear direction. Furthermore, the phrase "distance D6" being greater than the distance D7 includes the case where the distance D7 is zero. That is, as shown in FIG. 11(b) , the inner surface 24d of the second legs 24g and the side surface of the first core 10 may be in contact with each other.

[0043] The present invention is not limited to the above-described embodiment, but includes various modifications and improvements as long as the object of the present invention is achieved.

[0044] The above embodiments encompass the following technical concepts: (1) A coil component comprising: a first core; a base portion having an accommodating recess formed therein and accommodating the first core in the accommodating recess; terminal portions provided on the base portion; at least one coil connected to the terminal portions and spirally arranged around a winding core portion of the first core and the base portion; and a second core arranged above the first core, wherein the second core includes a flat portion and legs extending from one end of the flat portion toward a bottom surface of the accommodating recess in an axial direction of the coil, the accommodating recess includes: a first space accommodating the winding core portion and a second space different from the first space and accommodating the legs, and the base portion has leg restricting portions arranged inward of the legs in the axial direction. (2) The coil component of (1), wherein the legs have inner surfaces facing the leg restricting portions, and an orthogonal direction perpendicular to the inner surfaces is inclined with respect to the axial direction. (2-1) A coil component in which the angle between the orthogonal direction and the axial direction is greater than 0 degrees and less than 10 degrees. (2-2) A coil component in which the angle between the orthogonal direction and the axial direction is greater than 0 degrees and less than 5 degrees. (2-3) A coil component in which the dimension of the lower surface of the leg in the width direction of the coil component is greater than the dimension of the upper surface of the core end in the width direction of the coil component. (3) The coil component of (2), in which the base portion has a pair of leg restricting portions arranged on both sides of the first core in the width direction of the base portion, and the leg is in contact with a first of the pair of leg restricting portions and spaced apart from a second of the pair of leg restricting portions. (3-1) A coil component in which a side surface of the leg facing outward in the axial direction abuts a side wall portion. (4) The coil component according to (3), wherein the leg portion has a protruding portion that protrudes inward in the orthogonal direction from the inner side surface, and the protruding portion is disposed between the pair of leg restricting portions. (4-1) The coil component according to (3), wherein the distance between the second side surface and the step portion in one restricting portion is greater than the distance between the second side surface and the step portion in another restricting portion.(5) A coil component according to any one of (1) to (4), wherein a side surface of the leg restricting portion facing the leg is inclined obliquely with respect to a placement direction when the second core is placed on the first core, and a distance between the leg restricting portion and a lower end of the leg is shorter than a distance between the leg restricting portion and an upper end of the leg. (5-1) A coil component, wherein the first side surface is inclined outward in the front-to-rear direction toward the bottom surface portion. (6) A coil component according to any one of (1) to (5), wherein a bottom surface portion defining the second space in the base portion has a pair of elevated portions protruding upward from a surface of the bottom surface portion on which the first core is placed and disposed on either side of the first core in the width direction of the base portion. (7) The coil component according to (6), wherein the lower surfaces of the legs and the upper surface of the one end are arranged opposite to each other, both end portions of the lower surfaces of the legs in the width direction of the base are arranged outward in the width direction from both end portions of the upper surface of the one end in the width direction, and both end portions of the bottom surface of the second core are arranged opposite to and spaced apart from the upper surface of the plateau portion. (8) The coil component according to any one of (1) to (7), wherein the second core has the legs at both end portions in the axial direction, and the first core is arranged between the two legs in the axial direction. (9) The coil component according to (8), wherein the distance between the first leg and the first core is greater than the distance between the second leg and the first core.

[0045] 1 coil component 10 first core, 10a upper surface, 10a1 upper surface end, 12 winding core portion, 14 core end 20 second core, 22 flat plate portion, 24 leg portion, 24a lower end, 24b upper end, 24c lower surface, 24d inner surface, 24e step portion, 24f first leg portion, 24g second leg portion, 24h lower surface end 30 base portion, 30a bottom surface portion, 30b bottom surface, 31 elevated portion, 32 accommodating recess, 34 first space, 35 winding core side portion, 36 second space, 37 side wall portion, 38 restricting portion, 38a first restricting portion, 38b second restricting portion, 38c first side surface, 38d second side surface 40 terminal portion, 42 connecting portion, 44 intermediate portion, 46 mounting portion 50 Coil, 51 first coil, 52 second coil, 53 winding portion, 54 lead-out portion

Claims

1. A coil component having a first core, a base portion in which a receiving recess is formed to receive the first core, a terminal portion provided on the base portion, at least one coil connected to the terminal portion and spirally disposed around a bobbin portion in the first core and around the base portion, and a second core disposed above the first core, wherein the second core includes a flat plate portion and a leg portion extending from one end portion of the flat plate portion toward the bottom surface of the receiving recess in the axial direction of the coil, the receiving recess includes a first space for receiving the bobbin portion and a second space different from the first space for receiving the leg portion, and the base portion has a leg restricting portion disposed on an inner side of the leg portion in the axial direction.

2. The coil component according to claim 1, wherein the leg portion has an inner surface facing the leg restricting portion side, and a direction orthogonal to the inner surface is inclined with respect to the axial direction.

3. The coil component according to claim 2, wherein the base portion has a pair of two leg restricting portions disposed on both sides of the first core in the width direction of the base portion, the leg portion is in contact with a first one of the pair of leg restricting portions, and is spaced apart from a second one of the pair of leg restricting portions.

4. The coil component according to claim 3, wherein the leg portion has a protruding portion protruding inward in the orthogonal direction from the inner surface, and the protruding portion is disposed between the pair of leg restricting portions.

5. The coil component according to any one of claims 1 to 4, wherein a side surface of the leg restricting portion facing the leg portion is inclined obliquely with respect to a mounting direction when the second core is mounted on the first core, and a distance between the leg restricting portion and a lower end portion of the leg portion is smaller than a distance between the leg restricting portion and an upper end portion of the leg portion.

6. The coil component according to any one of claims 1 to 5, wherein a bottom surface portion defining the second space in the base portion has a pair of two raised portions protruding upward from a surface on which the first core is mounted in the bottom surface portion and disposed sandwiching the first core in the width direction of the base portion.

7. The lower surface of the leg portion and the upper surface of the one end portion are disposed opposite to each other, and both end portions of the lower surface of the leg portion in the width direction of the base portion are disposed outside in the width direction than each of both end portions of the upper surface of the one end portion in the width direction, and both end portions on the bottom surface of the second core are spaced apart from and opposed to the upper surface of the raised portion. The coil component according to claim 6.

8. The second core has the leg portions at both end portions in the axial direction, and the first core is disposed between the two leg portions in the axial direction. The coil component according to any one of claims 1 to 7.

9. The distance between the first leg portion and the first core is greater than the distance between the second leg portion and the first core. The coil component according to claim 8.

Images