Coil bobbin, coil component, and method for manufacturing coil bobbin

Abstract

A coil bobbin (10) comprises: a winding (120); a first bobbin (111); and a second bobbin (112). The first bobbin (111) and the second bobbin (112) are arranged side by side such that the axial directions are aligned with each other. The winding (120) is wound on the first bobbin (111) and the second bobbin (112) in a continuous manner, and is passed from the first bobbin (111) through an internal space (130), which is held between the first bobbin (111) and the second bobbin (112) arranged side by side, to the second bobbin (112). In addition, the winding (120) has a slacking part (121) in the internal space (130).

Description

Coil bobbin, coil component, and method of manufacturing the coil bobbin

[0001] The present invention relates to a coil bobbin having a plurality of bobbins around which a winding is wound continuously, a coil component including such a coil bobbin, and a method for manufacturing such a coil bobbin.

[0002] Some coil components have two bobbins arranged side by side along the axial direction, with a continuous winding wound across the two bobbins. Specifically, a winding is wound from one end to the other end of one of the two side by side bobbins, and then a winding is wound from the other end to one end of the adjacent other bobbin.

[0003] Regarding this type of technology, Patent Document 1 below discloses an inductor component in which a single winding (9, 10) is wound continuously around two coil bobbins (21, 22) arranged side by side with their axial directions aligned. As shown in Figure 1(b) of Patent Document 1, the winding (9, 10) is wound from the lower end to the upper end of one (e.g., the left) coil bobbin (21), passes from the left coil bobbin (21) to the right coil bobbin (22), and is wound from the upper end to the lower end of the right coil bobbin (22). More specifically, the winding (9, 10) wound from the lower end to the upper end of the left coil bobbin (21) is routed over a flange portion (24) on the upper end side of the left coil bobbin (21). The windings (9, 10) run along the outer periphery of the inductor component, pass over the flange (24), and are passed from the left coil bobbin (21) to the right coil bobbin (22), and are wound from the upper end to the lower end of the right coil bobbin (22).

[0004] Japanese Patent Application Laid-Open No. 2000-182844

[0005] A winding device is generally used to wind a wire around a bobbin. Specifically, a wire supply unit, such as a nozzle for unwinding the wire, or a bobbin serving as a winding core is rotated in the winding device to wind the wire around the bobbin. Simultaneously with the winding of the wire, the wire supply unit or the bobbin is moved in the axial direction of the bobbin to wind the wire so that the winding is parallel to the bobbin. When winding a continuous wire around each of two coil bobbins (21, 22) arranged side by side with their axial directions aligned with each other, as in Patent Document 1, when winding a wire around one of the coil bobbins, interference may occur between the other coil bobbin adjacent to the coil bobbin and a part of the winding device, such as the wire supply unit. For example, if the position of the wire supply unit of a winding device is fixed and a coil bobbin is rotated while winding, other coil bobbins located radially adjacent to the coil bobbin rotate around the axis of the coil bobbin as the coil bobbin rotates, resulting in interference with the wire supply unit of the winding device. Also, even if the position of the coil bobbin is fixed and the wire supply unit moves around the axis of the coil bobbin to wind a wire, the wire supply unit moving circumferentially around the coil bobbin will interfere with the other nearby coil bobbins. To prevent interference between the wire supply unit and the coil bobbin, a gap must be provided between the two coil bobbins so that the wire supply unit can pass between them when winding the wire. However, providing a gap between the coil bobbins increases the overall size of the coil component. In order to miniaturize coil components without leaving gaps between the coil bobbins, it is necessary to wind the wire using a special winding method while avoiding interference between the wire supply unit and the coil bobbin, which reduces the efficiency of the winding process.

[0006] The present invention has been made in consideration of the above-mentioned problems, and provides a method for manufacturing a coil bobbin that reduces interference between a winding device and a coil bobbin during the winding process and that enables a highly efficient winding process, as well as a coil bobbin that enables such manufacturing.

[0007] According to the present invention, there is provided a coil bobbin having a winding and a first bobbin and a second bobbin arranged side by side so that their axial directions are aligned with each other, wherein the winding is wound continuously across the first bobbin and the second bobbin and is passed from the first bobbin to the second bobbin through an inner space sandwiched between the side by side first and second bobbins, and wherein the coil bobbin has a slack portion in the inner space.

[0008] The present invention provides a coil component comprising the above-described coil bobbin, and a core having magnetic legs inserted through each of the first and second bobbins in the winding axis direction of the winding, and constructed by combining a plurality of magnetic members, wherein the first and second bobbins have a winding shaft portion around which the winding is wound, and a flange portion formed on one end and the other end of the first and second bobbins, respectively, protruding from the winding shaft portion in a direction intersecting the axial direction, the flange portion at one end or the other end of each of the first and second bobbins having a protrusion on an outer surface opposite to the winding shaft portion, and at least one of the magnetic members is arranged to straddle the flange portion of the first bobbin and the flange portion of the second bobbin, and a protrusion is arranged around the magnetic member.

[0009] According to the present invention, there is provided a method for manufacturing a coil bobbin having a winding and a first bobbin and a second bobbin arranged side by side, each having a winding shaft portion around which the winding is wound, the method including: a winding step of winding the winding continuously across the winding shaft portion of the first bobbin and the winding shaft portion of the second bobbin, with the first bobbin and the second bobbin arranged vertically so that the winding shaft portions are aligned in a substantially straight line; and a folding step of folding the first bobbin and the second bobbin and arranging them side by side, with a bridge portion, which is a length region of the winding that spans the first bobbin and the second bobbin, on the inside.

[0010] The coil bobbin of the above invention can be manufactured by winding the winding continuously around two bobbins arranged vertically so that they are aligned in a substantially straight line in the axial direction during the winding process, and then folding the two bobbins and arranging them horizontally so that their axial directions are aligned. When winding the winding around two bobbins arranged vertically, no other bobbins are present in the radial direction of the one bobbin around which the winding is wound, preventing interference between the winding device and the coil bobbins.

[0011] According to the coil bobbin, coil component, and coil bobbin manufacturing method of the present invention, interference between the winding device and the coil bobbin in the winding process can be reduced, and the efficiency of the winding process can be increased.

[0012] 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.

[0013] 4 is a perspective view of a coil bobbin according to a first embodiment of the present invention (however, illustration of windings is omitted); FIG. 5 is a perspective view of a coil bobbin according to the first embodiment (however, illustration of a second bobbin and windings wound around the second bobbin is omitted); FIG. 6 is a top view of a coil bobbin according to the first embodiment; FIG. 7 is a front view of a coil bobbin according to the first embodiment; FIG. 8 is a longitudinal cross-sectional view of a coil bobbin according to the first embodiment taken along the dashed dotted line shown in FIG. 3, as viewed in the direction of arrow V-V; FIG. 9 is a transverse cross-sectional view of a coil bobbin according to the first embodiment taken along the dashed dotted line shown in FIG. 4, as viewed in the direction of arrow VI-VI; FIG. 10 is a perspective view of a coil bobbin in an unfolded state according to the first embodiment; FIG. 11 is a side view of a coil bobbin according to the first embodiment in an unfolded state, as viewed from the side where a recess is formed; FIG. 12 is a perspective view of a coil component according to the first embodiment; FIG. 13 is a perspective view of a coil component according to the first embodiment (however, illustration of terminal portions is omitted); FIG. 14 is a longitudinal cross-sectional view of a coil component according to the first embodiment (however, illustration of windings and terminal portions is omitted).

[0014] The various components of the coil bobbin and 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. Furthermore, although the coil bobbin manufacturing method of the present invention may be described using multiple steps listed in order, the order of the steps does not limit the order or timing of performing the multiple steps. Therefore, when implementing the coil bobbin manufacturing method of the present invention, the order of the multiple steps can be changed as long as it does not cause any problems in terms of the content, and some or all of the timing of performing the multiple steps may overlap with each other.

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, corresponding components are denoted by the same reference numerals, and redundant description will be omitted as appropriate. In this embodiment, the axial direction of the first bobbin and the second bobbin is referred to as the vertical direction, and the direction perpendicular to the vertical direction is sometimes referred to as the horizontal direction. Furthermore, when the first bobbin and the second bobbin are arranged horizontally, the direction perpendicular to both the direction in which the first bobbin 111 and the second bobbin 112 are lined up and the vertical direction is sometimes referred to as the front-to-rear direction of the coil bobbin 10 and the bobbin 110. For example, the direction going back and forth between the rear and front sides of the page in FIG. 5 and the up-to-down direction of the page in FIG. 6 are the front-to-rear direction. Furthermore, in the folded state, the side of the coil bobbin 10 and the bobbin 110 having the protruding region and the recessed portion is referred to as the "upper side," and the opposite side is referred to as the "lower side." For example, in FIGS. 5 and 11, the upper side of the page is the "upper side," and the lower side of the page is the "lower side."

[0016] First Embodiment (Coil Bobbin) FIG. 1 is a perspective view showing an example of a coil bobbin according to a first embodiment of the present invention.

[0017] First, an overview of the coil bobbin 10 of this embodiment will be described. The coil bobbin 10 has a winding 120, a first bobbin 111, and a second bobbin 112. The first bobbin 111 and the second bobbin 112 are arranged side by side so that their axial directions are aligned with each other. The winding 120 is wound continuously across the first bobbin 111 and the second bobbin 112, and is passed from the first bobbin 111 to the second bobbin 112 through an inner space 130 sandwiched between the first bobbin 111 and the second bobbin 112 arranged side by side. The winding 120 also has a slack portion 121 in the inner space 130.

[0018] Next, the coil bobbin 10 of this embodiment will be described in detail. Here, the coil bobbin 10 is a component having one or more bobbins 110 and around which the winding 120 is wound. In this embodiment, a component having two bobbins 110 around which the winding 120 is wound may also be referred to as the coil bobbin 10. The bobbin 110 is a component that serves as a winding shaft around which the winding 120 is wound. The bobbin 110 is an elongated object that is long in the winding axis direction. In this embodiment, the coil bobbin 10 has a first bobbin 111 and a second bobbin 112 as the bobbins 110. The axial direction of the first bobbin 111, the second bobbin 112, and the winding shaft portion 113 described later is the extension direction of the first bobbin 111 or the second bobbin 112. In this embodiment, the bobbin 110 has a rectangular cross section, but it may also be circular, square, or polygonal. Furthermore, although the bobbin 110 in this embodiment is a straight-axis bobbin with a straight center line of the winding axis, the bobbin 110 may have a non-linear shape, such as an arc shape. For example, two bobbins may each have a semicircular shape, so that when the two bobbins 110 are arranged side by side, they form a ring shape as a whole. The winding 120 is a wire wound around the first bobbin 111 and the second bobbin 112. The winding 120 is made of a metal conductor such as copper or aluminum. Here, the fact that the first bobbin 111 and the second bobbin 112 are arranged side by side with their axial directions aligned means that the winding axis direction of one of the two bobbins (e.g., the first bobbin 111) has a winding axis direction component of the other bobbin (the second bobbin 112). Preferably, the winding axis direction of one of the first bobbins 111 and the second bobbin 112 has a winding axis direction component that is greater than the orthogonal component relative to the winding axis direction of the other bobbin. More preferably, the first bobbin 111 and the second bobbin 112 are parallel or substantially parallel. The axial direction of the first bobbin 111 and the axial direction of the second bobbin 112 do not have to be completely parallel, but may be intersecting or twisted. Hereinafter, the state in which the first bobbin 111 and the second bobbin 112 are arranged side by side with their axial directions aligned with each other as shown in FIG. 1 may be referred to as a folded state.In addition, in the winding process of the coil bobbin manufacturing method described below, the first bobbin and the second bobbin are arranged in a substantially linear manner in the axial direction as shown in Figures 7 and 8, and this arrangement state may be referred to as an unfolded state.

[0019] As shown by the two-dot chain line in Figure 6, the inner space 130 is a space sandwiched between the first bobbin 111 and the second bobbin 112 when the first bobbin 111 and the second bobbin 112 are arranged side by side. In this embodiment, flanges 116 (upper flange 116 and lower flange 114) described below are formed on both ends of the first bobbin 111 and the second bobbin 112, and the upper flanges 116 and the lower flanges 114 abut against each other. In this embodiment, the inner space 130 is a space sandwiched between the upper flange 116 and the lower flange 114, and is also a space sandwiched between the winding shaft portions 113 of the first bobbin 111 and the second bobbin 112. As shown in Figure 6, the inner space 130 has at least two opening surfaces 131 in the lateral direction. The opening surface 131 is an imaginary surface that connects the most protruding portion of the first bobbin 111 in one direction in the front-to-rear direction and the most protruding portion of the second bobbin 112 in the same direction when the two bobbins 110 are in a folded state. In the present embodiment, as shown in Fig. 6, one opening surface 131 (131a) is an imaginary surface that connects the circumferential surface of the winding shaft portion 113 on the front side (lower side of the paper) of the first bobbin 111 and the circumferential surface of the winding shaft portion 113 on the front side of the second bobbin 112, and the other opening surface 131 (131b) is an imaginary surface that connects the circumferential surface of the winding shaft portion 113 on the rear side (upper side of the paper) of the first bobbin 111 and the circumferential surface of the winding shaft portion 113 on the rear side of the second bobbin 112. In this embodiment, the inner space 130 is defined by the opposing side surfaces of the first bobbin 111 and the second bobbin 112, the upper flange 116 and the lower flange 114 of the first bobbin 111 and the second bobbin 112, and the opening surface 131 (131a and 131b). If the bobbin 110 does not have the flange 116, the axial extent of the inner space 130 extends to both axial ends of the first bobbin 111 and the second bobbin 112. Even if the flange is provided not at the end of the bobbin 110 but at the middle of the axial direction and a winding is wound on both sides, the axial extent of the inner space 130 also extends to both axial ends of the first bobbin 111 and the second bobbin 112.

[0020] Here, the winding 120 being wound continuously across the first bobbin 111 and the second bobbin 112 means that one common winding 120 is wound around each of the first bobbin 111 and the second bobbin 112. Specifically, one end of the winding 120 wound around the first winding shaft portion 113a (winding shaft portion 113 of the first bobbin 111) located at the upper end of the first winding shaft portion 113a is connected to one end of the winding 120 wound around the second winding shaft portion 113b (winding shaft portion 113 of the second bobbin 112) located at the upper end of the second winding shaft portion 113b. Here, the winding 120 spanning between the first bobbin 111 and the second bobbin 112 when the first bobbin 111 and the second bobbin 112 are in a folded state is referred to as a boundary portion 123. Specifically, the boundary portion 123 is a length region of the winding 120 that connects the point at which the upper end of the winding 120 wound around the first winding shaft portion 113a separates from the first winding shaft portion 113a and the point at which the upper end of the winding 120 wound around the second winding shaft portion 113b touches the second winding shaft portion 113b. In this embodiment, the boundary portion 123 is a length region of the winding 120 that extends from position X (see FIG. 6 ) where winding around the first bobbin 111 ends and the winding 120 separates from the first bobbin 111 to position Y (see FIG. 6 ) where the winding 120 touches the second bobbin 112 and winding around the second bobbin 112 begins. The boundary portion 123 includes a jumper portion 122 (see FIG. 8 ), which will be described later. The winding 120 being passed from the first bobbin 111 to the second bobbin 112 through the internal space 130 means that at least a portion of the boundary 123 is present in the internal space 130. Specifically, as shown in FIG. 6 , one end of the boundary 123 present in the internal space 130 passes through one opening surface 131a of the internal space 130 and leads to the outside of the internal space 130, and the other end of the boundary 123 present in the internal space 130 passes through the other opening surface 131b of the internal space 130 and leads to the outside of the internal space 130. A portion of the boundary 123 may be present outside the internal space 130. As shown in FIG. 2 , a cross section of the winding 120 is shown in the middle of the boundary 123 because the bent portion protrudes outward from the cross section shown in FIG. 4 . Here, the cross section of the winding 120 is shown as a circle, but in reality it may be elliptical.

[0021] In this embodiment, the winding 120 is wound continuously around the two bobbins 110, for example, as shown below. The winding 120 is wound around the first winding shaft portion 113a from the lower end to the upper end of the first bobbin 111 in the axial direction, in a clockwise direction when viewed from above. The winding 120 then passes through the inner space 130 between the first bobbin 111 and the second bobbin (passing from the back of the page to the front of the page in FIG. 4 between the first bobbin 111 and the second bobbin 112) and reaches the upper end of the second winding shaft portion 113b. The winding 120 is then wound around the second bobbin 112 from the upper end to the lower end of the second winding shaft portion 113b in a counterclockwise direction when viewed from above. The winding direction of the winding 120 is not limited to this. For example, the winding 120 may be wound around the first winding shaft portion 113a in a counterclockwise direction when the first bobbin 111 is viewed from above, and the winding 120 may be wound around the second winding shaft portion 113b in a clockwise direction when the second bobbin 112 is viewed from above. When a core 140 (U core 142 and I core 143) described below is attached to the coil bobbin 10, the coil component 100 has a closed magnetic circuit structure. In the coil component 100, magnetic field lines generated in the coil pass through the cores and form loops. By winding the winding 120 so that the winding directions of the winding 120 on the first winding shaft portion 113a and the second winding shaft portion 113b are opposite to each other when viewed from the same side (e.g., the top) of the coil bobbin 10, the coil component 100 is configured in which the winding 120 is wound in the same direction with respect to the direction of the magnetic field lines.

[0022] Here, the slack portion 121 refers to a partial length region of the winding 120 at or near the boundary portion 123, which is looser than other length regions of the winding 120 wound at or near the middle portion of the winding shaft portion 113. Specifically, the slack portion 121 refers to a length region of the winding 120 at or near the boundary portion 123 that corresponds to any of the following: a portion of the winding 120 at or near the boundary portion 123 that is subjected to lower tension than the winding 120 wound at the lower end of the winding shaft portion 113; a portion of the boundary portion 123 where the winding 120 is not linear; or a portion of the winding 120 where the winding diameter is larger than the winding 120 wound at the lower end of the winding shaft portion 113. Here, the winding 120 wound at the lower end of the winding shaft portion 113 refers to, for example, the winding 120 wound at or near the middle portion of the first winding shaft portion 113a or the second winding shaft portion 113b. In this embodiment, as shown in FIG. 2 , the boundary portion 123 is not linear but has a bent portion. Specifically, the boundary portion 123 has an excess length equal to the length of a transition portion 122 (described later), and the excess length of the winding 120 is folded halfway along the boundary portion 123. In this embodiment, the boundary portion 123 serves as the slack portion 121. While this embodiment illustrates an aspect in which only the boundary portion 123 spanning the first bobbin 111 and the second bobbin 112 serves as the slack portion 121, this is not limiting. For example, the winding 120 wound around the first bobbin 111 or the second bobbin 112 may also serve as the slack portion 121. For example, the excess length of the boundary portion 123 may cause the winding 120 to loosen radially at the upper end of the first winding shaft portion 113a or the second winding shaft portion 113b. Hereinafter, the radial direction refers to the direction extending radially from the axial center of the bobbin 110 toward the periphery. Hereinafter, the above-described direction will also be referred to as the radial direction when the cross section of the winding shaft portion 113 or the flange portion 116 is polygonal rather than circular. When the winding 120 wound around the upper end of the winding shaft 113 is wound with a lower tension than the winding 120 wound around the middle of the winding shaft 113 due to loose winding, a partial length region of the winding 120 is also included as the slack portion 121. In this case, the winding 120 wound around the winding shaft 113 to form the slack portion 121 may or may not be in contact with the winding shaft 113.Furthermore, if the winding diameter of the winding 120 wound around the upper end of the winding shaft portion 113 due to loose winding is larger than that of the winding 120 wound around the middle portion of the winding shaft portion 113, the winding 120 wound around the winding shaft portion 113 with a larger winding diameter than that of the middle portion of the winding shaft portion 113 is also included in the slack portion 121.

[0023] In this embodiment, the slack portion 121 is twisted relative to the extension direction of the winding 120. Specifically, it is twisted by an angle that the first bobbin 111 and the second bobbin 112 rotate in a folding process described below. For example, when the first bobbin 111 and the second bobbin 112 in the unfolded state are folded 180 degrees in the folding process so that the first bobbin 111 and the second bobbin 112 are arranged side by side, a 180-degree twist occurs in the slack portion 121. When the first bobbin 111 and the second bobbin 112 are folded from the unfolded state, the transition portion 122 described below is also folded. As shown in FIG. 2 , in this embodiment, the transition portion 122 (see FIG. 8 ) is still in a folded shape even in the folded state. This is because the direction of rotation of winding 120 when slack portion 121 tries to eliminate twist is opposite to the direction of rotation of jumper portion 122 when it tries to straighten the folded shape, preventing jumper portion 122 from straightening. In this way, twisting slack portion 121 makes it easier to maintain jumper portion 122, which will be described later, in its folded shape. This prevents the winding 120 wound around winding shaft portion 113 from loosening due to the excess length of winding 120 corresponding to jumper portion 122.

[0024] The twist in winding 120 may cause boundary 123 to be approximately straight, the tension of winding 120 wound at the upper end of winding shaft 113 to be equal to that of winding 120 wound at the intermediate portion of winding shaft 113, or the winding diameter of winding 120 may not be larger than that of winding 120 wound at the intermediate portion of winding shaft 113. In this case, a partial length region of twisted winding 120 is designated as slack portion 121. Preferably, regardless of the presence or absence of a twist, slack portion 121 is a portion of winding 120 on the upper end of winding shaft 113 that is subjected to lower tension than winding 120 wound at the lower end of winding shaft 113, as described above, boundary 123 where winding 120 is not straight, or a portion that has a larger winding diameter than winding 120 wound at the lower end of winding shaft 113.

[0025] Because the winding 120 has the slack portion 121 and the portion spanning from the first bobbin 111 to the second bobbin 112 has excess length, it is possible to manufacture the coil device 100 using a manufacturing method in which the winding 120 is continuously wound around the first bobbin 111 and the second bobbin 112 in an unfolded state, as described below. Furthermore, because the winding 120 passes through the inner space 130 and spans between the first bobbin 111 and the second bobbin 112, it is possible to manufacture the coil device 100 using a manufacturing method in which the winding 120 is continuously wound in the same direction from the first bobbin 111 to the second bobbin 112 in an unfolded state, as described below. Having a portion of the slack portion 121 located in the inner space 130 between the first bobbin 111 and the second bobbin 112 prevents the slack portion 121 from being exposed to the outside of the coil bobbin 100. This prevents the slack portion 121 from being cut or worn, which could result in a decrease in performance of the coil device 100 and an unexpected shortening of the insulation distance.

[0026] The first bobbin 111 and the second bobbin 112 have a winding shaft portion 113 around which the winding 120 is wound. The first bobbin 111 and the second bobbin 112 have a protruding region extending in the circumferential direction of the winding shaft portion 113 at one end of the first bobbin 111 and the second bobbin 112. The winding shaft portion 113 is the portion of the first bobbin 111 or the second bobbin 112 around which the winding 120 is wound. If the first bobbin 111 and the second bobbin 112 have a protruding region such as a flange portion 116 described below, the winding shaft portion 113 is a region closer to the center in the axial direction than the protruding region such as the flange portion 116. If the first bobbin 111 and the second bobbin 112 have flange portions 116 (upper flange portion 116 and lower flange portion 114) at both ends, the winding shaft portion 113 is a region sandwiched between the upper flange portion 116 and the lower flange portion 114. The protruding region is a region that has a protrusion that protrudes from the winding shaft portion 113 in a direction intersecting the axial direction and extends around the winding shaft portion 113 in the circumferential direction, including the protrusion. In this embodiment, the protruding region is formed at the tip of the first bobbin 111 and the second bobbin 112, but may also be provided midway along the axial length of the first bobbin 111 and the second bobbin 112. In this embodiment, as shown in FIG. 1 , the entire protruding region is a protrusion, that is, the protruding region is a flange portion 116 described below, but this is not limiting. For example, only a portion of the protruding region may have a protrusion, and the protruding region other than the protrusion may be continuous with the circumferential surface of the winding shaft portion 113. Furthermore, the protruding region may have multiple protrusions.

[0027] The protruding region (upper flange 116) has a recess 115 formed in a concave shape extending from the outer periphery of the protruding region toward the winding shaft portion 113. The recess 115 is provided on the protruding portion of the protruding region and is the portion of the upper flange portion 116 that forms the recess. The winding 120 is passed through the recess 115 during the winding process of the winding 120, which will be described later. The radial height of the recess 115, based on the circumferential surface of the winding shaft portion 113, may be lower than the height of the protruding portion of the protruding region. The recess 115 may be higher than the height of the circumferential surface of the winding shaft portion 113 or may be the same height as the circumferential surface of the winding shaft portion 113. The first bobbin 111 and the second bobbin 112 are arranged so that at least a portion of each recess 115 is located inside the space sandwiched between the first bobbin 111 and the second bobbin 112. Here, "at least a portion of the recess 115 being located inside the area sandwiched between the first bobbin 111 and the second bobbin 112" means that at least a portion of the opening of the recess 115 is located inside the area sandwiched between the first bobbin 111 and the second bobbin 112. The opening of the recess 115 is a virtual periphery of the protrusion in the case where the recess 115 is not formed in the protrusion. In this embodiment, the recess 115 of the first bobbin 111 and the recess 115 of the second bobbin 112 face each other. That is, the recess 115 of the first bobbin and the recess 115 of the second bobbin 112 are provided at the same height in the axial direction of the first bobbin 111 and the second bobbin 112, face each other in the circumferential direction of the first bobbin 111 and the second bobbin 112, and the recesses 115 of the first bobbin 111 and the second bobbin 112 are connected to each other when viewed from the top surface of the coil bobbin 10. However, the present invention is not limited to this, and the recess 115 of the first bobbin 111 and the recess 115 of the second bobbin 112 do not have to face each other. In other words, the recess 115 of the first bobbin 111 and the recess 115 of the second bobbin 112 may be provided offset in the circumferential direction or axial direction of the first bobbin 111 and the second bobbin 112.

[0028] By providing the protruding region and the recessed portion 115 in the protruding region, the structure allows for the winding step of the manufacturing method of the coil bobbin 10, which will be described later. That is, by passing the winding 120 through the recessed portions 115 of the first bobbin 111 and the second bobbin 112 in the winding step, the position of the winding 120 (the transition portion 122, which will be described later) spanning from the first bobbin 111 to the second bobbin 112 in the unfolded state can be determined. This prevents the winding 120 from shifting laterally during the folding step in which the first bobbin 111 and the second bobbin 112 are folded side-by-side, and allows for the structure to be folded with the transition portion 122 facing inward. The width (circumferential dimension) of the recessed portion 115 may be as narrow as the outer diameter of the winding 120 or may be longer than the outer diameter of the winding. To prevent the winding 120 from shifting laterally during the folding step, the width of the recessed portion 115 may be equal to or less than one-fourth the circumferential length of the protruding region. Furthermore, to more effectively prevent lateral displacement of winding 120, the width of recess 115 may be set to be equal to or less than twice the outer diameter of winding 120. To prevent lateral displacement of winding 120, the depth of recess 115 in the radial direction of winding shaft portion 113 may be set to be equal to or greater than the diameter of the cross section of winding 120.

[0029] Furthermore, by providing the protruding region, the winding 120 is locked by the protruding portion, and it is possible to prevent the winding 120 from loosening from the protruding region in the direction opposite to the winding shaft portion 113. When multiple protruding portions are provided in the protruding region, it is also possible to effectively prevent the winding 120 from loosening at multiple locations.

[0030] 7 and 8, when the first bobbin 111 and the second bobbin 112 are arranged linearly with their ends, where the protruding regions (upper flange portions 116) are provided, abutting against each other, the slack portion 121 has a length that allows the winding 120 to pass through the recessed portion 115 and span between the first bobbin 111 and the second bobbin 112. "The winding 120 passing through the recessed portion 115" means that the winding 120 is arranged so as to intersect with the extending direction of the protruding regions, and a portion of the winding 120 is surrounded by the recessed portion 115 on the surface where the protruding regions extend. More specifically, the length of slack portion 121 is equal to or greater than the sum of the height of the bottom of recess 115 of first bobbin 111 from the circumferential surface of winding shaft portion 113, the height of the bottom of recess 115 of second bobbin 112, and distance L1 (see FIG. 8 ) from recess 115 of first bobbin 111 to recess 115 of second bobbin 112 when first bobbin 111 and second bobbin 112 are arranged linearly with their ends having protruding regions abutting against each other. Here, the height of the bottom of recess 115 from the circumferential surface of winding shaft portion 113 refers to the height of the deepest part of recess 115 in the radial direction, based on the circumferential surface of winding shaft portion 113. Furthermore, when the first bobbin 111 and the second bobbin 112 are arranged linearly with their ends having the protruding regions abutting against each other, the distance from the recess 115 of the first bobbin 111 to the recess 115 of the second bobbin 112 is the distance connecting one point on the winding shaft portion 113 side of the recess 115 of each of the first bobbin 111 and the second bobbin 112. In this embodiment, the height of the recess 115 is the same as the height of the circumferential surface of the winding shaft portion 113, and therefore the height of the recess 115 from the circumferential surface of the winding shaft portion 113 in the first bobbin 111 and the height of the recess 115 in the second bobbin 112 are substantially zero. When the first bobbin 111 and the second bobbin 112 are arranged vertically as shown in FIG. 7 , the recesses 115 of each are in communication with each other. In this case, the distance from the recess 115 of the first bobbin 111 to the recess 115 of the second bobbin 112 is the distance from the inner surface of the upper flange 116a of the first bobbin 111 (the surface of the flange 116 facing the winding shaft 113) to the inner surface of the upper flange 116b of the second bobbin 112.That is, the distance from the recess 115 of the first bobbin 111 to the recess 115 of the second bobbin 112 includes the thickness of the upper flange portions 116 (116a, 116b) of the first bobbin 111 and the second bobbin 112 and the length between the upper flange portion 116a of the first bobbin 111 and the upper flange portion 116b of the second bobbin 112.

[0031] In a winding process described below, the first bobbin 111 and the second bobbin 112 are in an unfolded state, and the winding 120 is wound around the first bobbin 111, for example, and then passed from the first bobbin 111 to the second bobbin 112 through the recess 115 of the first bobbin 111 and the recess 115 of the second bobbin 112, and then wound around the second bobbin 112. When the first bobbin 111 and the second bobbin 112 transition to a folded state, the crossover portion 122, which is the winding 120 that was disposed between the recess 115 of the first bobbin 111 and the recess 115 of the second bobbin 112 in the unfolded state, becomes part of the slack portion 121. In other words, since the slack portion 121 has at least a length that enables it to cross over between the first bobbin 111 and the second bobbin 112 through the recess 115 in the unfolded state, the coil bobbin 10 can be manufactured by a method for manufacturing the coil bobbin 10 described below.

[0032] More specifically, in the unfolded state, the winding 120 wound around the first winding shaft portion 113a moves radially from the circumferential surface of the first winding shaft portion 113a onto the recess 115, crosses from the recess 115 of the first bobbin 111 to the recess 115 of the second bobbin 112, descends from the recess 115 of the second bobbin 112 onto the circumferential surface of the second winding shaft portion 113b, and is wound around the second winding shaft portion 113b. In this embodiment, because the height of the bottom of the recess 115 is zero, the winding 120 wound around the first winding shaft portion 113a does not move radially onto the upper flange portion 116a, but passes from the recess 115 of the first bobbin 111 to the recess 115 of the second bobbin 112, and is then wound around the second winding shaft portion 113b. Slack portion 121 has a length equal to or greater than the sum of the height of the bottom of recess 115 from the circumferential surface of first winding shaft portion 113a, the height of the bottom of recess 115 from the circumferential surface of second winding shaft portion 113b, and the distance between recess 115 of first bobbin 111 and recess 115 of second bobbin 112. This allows winding 120 to move from the circumferential surface of first winding shaft portion 113a onto recess 115 of first bobbin 111, cross between recesses 115 of the first and second bobbins, and descend from recess 115 of second bobbin 112 onto the circumferential surface of second winding shaft portion 113b.

[0033] As shown in FIGS. 4 and 5 , the protruding region in this embodiment is a flange 116 that protrudes from the winding shaft portion 113 of the first bobbin 111 or the second bobbin 112 in a direction intersecting the axial direction. The flange 116 is a portion that protrudes from the circumferential surface of the winding shaft portion 113 over substantially the entire circumference of the protruding region. In this embodiment, the flange 116 protrudes over the entire circumference except for the recessed portion 115 of the protruding region, but this is not limited to this. A portion of the flange 116 may not protrude and may be continuous with the circumferential surface of the winding shaft portion 113. That is, the flange 116 may have one or more recessed portions 115. In this embodiment, the flange 116 protrudes perpendicular to the axial direction, but this is not limited to this. The winding 120 is stretched from the first bobbin 111 to the second bobbin 112 on the winding shaft portion 113 side of the outer surface 116 c of the upper flange 116. In this embodiment, the entire length of boundary portion 123 is located closer to winding shaft portion 113 than outer surface 116c of upper flange 116a. That is, winding 120 separates from first winding shaft portion 113a on the winding shaft portion 113 side of outer surface 116c of upper flange 116a, passes through inner space 130 located closer to winding shaft portion 113 than outer surface 116c of upper flange 116b, and contacts second winding shaft portion 113b on the winding shaft portion 113 side of outer surface 116c of upper flange 116b, thereby starting winding. Alternatively, part of slack portion 121 may be located on the opposite side of flange 116 from winding shaft portion 113. For example, if slack portion 121 is long, part of slack portion 121 may protrude above upper flange 116.

[0034] By providing upper flange 116 so that the protruding region extends over substantially the entire circumference, winding 120 that tends to loosen axially outward from winding shaft 113 can be appropriately retained over substantially the entire circumference. The radial height of flange 116 is sufficient to retain winding 120. Specifically, the height of flange 116 is preferably equal to or greater than the cross-sectional diameter of winding 120. Furthermore, recess 115 in this embodiment is a notch formed by cutting out flange 116. Providing a notch in flange 116 allows slack portion 121 of winding 120 to be shorter than in a case where flange 116 does not have a notch and the entire circumference of the protruding region protrudes beyond the circumferential surface of winding shaft 113. For example, if flange 116 does not have a notch, winding 120 wound around the circumferential surface of first winding shaft 113a would ride up onto upper flange 116a of first bobbin 111, cross over to upper flange 116b of second bobbin 112, and then descend from upper flange 116b of second bobbin 112 to the circumferential surface of second winding shaft 113b, so slack 121 would need to have a length equal to the height of upper flange 116 (116a and 116b). Therefore, if upper flange 116 is provided with a notch, the height of upper flange 116 that winding 120 rides up becomes smaller or even zero, and the length of slack 121 required to cross from first bobbin 111 to second bobbin 112 can be shortened. Furthermore, since the entire length of the boundary portion 123 is passed from the first bobbin 111 to the second bobbin 112 on the side of the winding shaft portion 113 closer to the outer surface 116c of the flange portion 116, the slack portion 121 is prevented from accidentally protruding outside the coil component and damaging or cutting the winding of the slack portion 121.

[0035] As shown in FIGS. 1 and 3 , the first bobbin 111 and the second bobbin 112 have concave-convex engaging portions 118 that engage with each other when arranged side by side with their axial directions aligned. The concave-convex engaging portions 118 are a combination of at least one pair of engaging recesses 118a (see FIG. 2 ) and engaging protrusions 118b (see FIG. 2 ). The engaging recesses 118a and the engaging protrusions 118b are provided on the sides of the first bobbin 111 and the second bobbin 112 that face each other when the first bobbin 111 and the second bobbin 112 are folded. The engaging protrusions 118b protrude radially. The engaging recesses 118a have a concave shape corresponding to the engaging protrusions 118b and are recessed axially from the periphery of the first bobbin 111 or the second bobbin 112. This allows the engaging recesses 118a and the engaging protrusions 118b to interlock with each other in the folded state. In this embodiment, the engaging protrusions 118b are shaped so that their widths gradually narrow in the protruding direction. For example, the shapes of the engaging protrusions 118b and the engaging recesses 118a can be semicircular, triangular, etc. The first bobbin 111 and the second bobbin 112 each have either the engaging recesses 118a or the engaging protrusions 118b. That is, the first bobbin 111 and the second bobbin 112 each have a pair or more of the concave-convex engaging portions 118 in total.

[0036] In this embodiment, as will be described later, flanges 116 (upper flange 116 and lower flange 114) are provided on both ends of the first bobbin 111 and the second bobbin 112. When the first bobbin 111 and the second bobbin 112 are in a folded state, the upper flanges 116 and the lower flanges 114 of the first bobbin 111 and the second bobbin 112 abut against each other. The engagement recesses 118a or the engagement protrusions 118b are provided on the sides of the upper flanges 116 and the lower flanges 114 of the first bobbin 111 and the second bobbin 112 that abut against each other, but this is not limitative. The concave-convex engagement portions 118 may be provided on the winding shaft portions 113 of the first bobbin 111 and the second bobbin 112. For example, when a protruding portion such as a flange is provided midway on the winding shaft portion 113 as in a modified example described below, the flanges of the first bobbin 111 and the second bobbin 112 may be provided with concave-convex engaging portions 118. Furthermore, when there is a portion that protrudes from the circumferential surface of the winding shaft portion 113 on the axially outer side of the flange portion 116, the concave-convex engaging portion 118 may be provided on the protruding portion. In this embodiment, the upper flange portion 116 and the lower flange portion 114 of the first bobbin 111 and the second bobbin 112 are provided with engaging recesses 118a or engaging protrusions 118b, respectively. Specifically, the upper flange portion 116 is provided with two pairs of concave-convex engaging portions 118 between the first bobbin 111 and the second bobbin 112, and the lower flange portion 114 is also provided with two pairs of concave-convex engaging portions 118. More specifically, each flange portion 116 has one engaging recess 118a and one engaging protrusion 118b. The concave-convex engaging portions 118 may be provided only on the upper flange 116 or the lower flange 114, or may be provided on both the upper flange 116 and the lower flange 114. Furthermore, only one pair of the concave-convex engaging portions 118 may be provided between the abutting flanges (116 a and 114 a) of the first bobbin 111 and the abutting flanges (116 b and 114 b) of the second bobbin 112, or multiple pairs may be provided.

[0037] The engagement of the first bobbin 111 and the second bobbin 112 by the concave-convex engaging portion 118 prevents the first bobbin 111 and the second bobbin 112 from shifting laterally relative to the engagement direction of the concave-convex engaging portion 118. This facilitates stable assembly of the coil component 100. Furthermore, because the engaging protrusion 118b has a shape that monotonically narrows in width toward the protruding direction, when the first bobbin 111 and the second bobbin 112 are folded from the unfolded state to the folded state, the concave-convex engaging portion 118 can be engaged with the engaging recess 118a without interfering with the engaging protrusion 118b.

[0038] In this embodiment, the first bobbin 111 and the second bobbin 112 have the same shape, including the shapes of the concave-convex engaging portions 118 and the protrusions 117 described below. Specifically, the concave-convex engaging portions 118 are formed at positions equidistant from the center of the side of the flange portion 116 on which the concave-convex engaging portions 118 are formed. Furthermore, the engaging recesses 118a, the engaging protrusions 118b, and the protrusions 117 on the first bobbin 111 and the second bobbin 112 are formed in positions and shapes that are rotationally symmetrical to each other when the coil bobbin 10 is viewed vertically in the folded state. This allows the first bobbin 111 and the second bobbin 112 to be manufactured using the same manufacturing equipment, thereby improving the productivity of the coil bobbin 10.

[0039] (Coil Component) Next, a coil component 100 including a coil bobbin 10 will be described. FIG. 9 is a perspective view of the coil component 100, and FIG. 10 is a perspective view of the coil component 100 from another perspective. FIG. 11 is a longitudinal cross-sectional view of the coil component 100. The coil component 100 includes a core 140 configured by combining the above-described coil bobbin 10 with multiple magnetic members. As shown in FIG. 11, the core 140 has magnetic legs 141 inserted in the winding axis direction of the winding 120 on the first bobbin 111 and the second bobbin 112, respectively. Here, the coil component 100 in this embodiment refers to a component used with the coil bobbin 10. However, the application is not limited thereto. The core 140 includes at least two magnetic members, which are integrally molded from a magnetic material such as ferrite. In this embodiment, the core 140 includes a U-shaped U-core 142 and an I-shaped I-core 143, but this is not limited thereto. For example, the core may include two U-shaped cores. The first bobbin 111 and the second bobbin 112 are provided with insertion holes in the axial direction, and one end of the U core 142 is inserted into each of the insertion holes 119 of the first bobbin 111 and the second bobbin 112 .

[0040] As described above, the first bobbin 111 and the second bobbin 112 each have a winding shaft portion 113 around which the winding 120 is wound, and flange portions (116, 114) formed at one end and the other end of the first bobbin and the second bobbin, respectively, protruding from the winding shaft portion 113 in a direction intersecting the axial direction. The upper flange portion 116 has a recess 115. The flange portion 116 at one end or the flange portion 116 at the other end of each of the first bobbin 111 and the second bobbin 112 has a protruding portion 117 on an outer surface 116c opposite the winding shaft portion 113. That is, the upper flange portion 116a of the first bobbin 111 and the upper flange portion 116b of the second bobbin 112 each have the protruding portion 117, or the lower flange portion 114a of the first bobbin 111 and the lower flange portion 114b of the second bobbin 112 each have the protruding portion 117. In this embodiment, a protrusion 117 is provided on the upper flange 116 of the first bobbin 111 and the second bobbin 112. The protrusion 117 is a portion that protrudes from the outer surface 116c of the flange 116 to the side opposite the winding shaft 113.

[0041] At least one of the magnetic members is disposed straddling the flange 116 of the first bobbin 111 and the flange 116 of the second bobbin 112, and a protrusion 117 is disposed around the magnetic member. Here, "the magnetic member is disposed straddling the flange 116 of the first bobbin 111 and the flange 116 of the second bobbin 112" means that a portion of the magnetic member is in contact with the flange 116 of the first bobbin 111 and another portion is in contact with the flange 116 of the second bobbin 112. In this embodiment, the I-core 143 is in contact with the outer surface 116c of the upper flange 116 of each of the first bobbin 111 and the second bobbin 112. In this embodiment, as shown in FIG. 9 , the surface of the I-core 143 in contact with the upper flange 116a of the first bobbin 111 and the upper flange 116b of the second bobbin 112 is rectangular. The protrusion 117 has an L-shape formed integrally by two intersecting straight lines, and the two straight lines are arranged along the sides of the magnetic member, but this is not limited to this. It is sufficient that the protrusion 117 is arranged near each side of the I-core 143 that contacts the flange 116 in a rectangular shape. For example, one protrusion 117 may be arranged on each of the four sides, or multiple protrusions 117 may be arranged in a line along the side. Furthermore, the protrusion 117 and the magnetic member (I-core 143) may be in contact with each other, or may be adjacent to each other without contacting each other.

[0042] In this embodiment, the protrusion 117 is provided on the upper flange 116, but it may also be provided on the lower flange 114. When the protrusion 117 is provided on the upper flange 116, the protrusions 117 of the first bobbin 111 and the second bobbin 112 are sandwiched between the outer surfaces 116c of the upper flanges 116 of the first bobbin 111 and the second bobbin 112 in the unfolded state. Furthermore, in the folded state, the I core 143 is disposed on the outer surface 116c of the upper flange 116, and the U core 142 is inserted from the lower end side of the coil bobbin 10. On the other hand, when the protrusion 117 is provided on the lower flange 114, the outer surfaces 116c of the upper flanges 116 of the first bobbin 111 and the second bobbin 112 come into contact with each other in the unfolded state. In addition, in the folded state, the I core 143 is disposed on the outer surface 116c of the lower flange 114, and the U core 142 is inserted from the upper end side of the coil bobbin 10. By providing the protrusions 117 on the lower flanges 114 of the first bobbin 111 and the second bobbin 112, the distance between the upper flanges 116 of the first bobbin 111 and the second bobbin 112 in the unfolded state is reduced, and the length of the bridge portion 122 spanning from the recess 115 of the first bobbin 111 to the recess 115 of the second bobbin 112 can be reduced. This reduces the length of the slack portion 121, making it possible to prevent the winding 120 from accidentally coming out of the coil device 100 in the folded state. When the protrusions 117 are provided on the upper flanges 116 of the first bobbin 111 and the second bobbin 112, the U-core 142 can be inserted from the lower end of the coil bobbin 10 to easily prevent the first bobbin 111 and the second bobbin 112 from returning from the folded state to the unfolded state. This is because the U-core 142 can regulate the rotation of the first bobbin 111 and the second bobbin 112 at the center where the first bobbin 111 and the second bobbin 112 are folded, i.e., at the lower end far from the upper end where the transition portion 122 is located. Furthermore, when the protrusions 117 are provided on the upper flange 116, the depth of the recess 115 may be more than half the height of the protrusions 117. Here, the height of the protrusions 117 refers to the height of the protrusions 117 axially outward from the surface of the flange 116. When the protrusion 117 is provided on the upper flange 116, the transition portion 122 of the winding 120, which will be described later, becomes longer by the height of the protrusion 117. By making the depth of the recess 115 at least half the height of the protrusion 117, it is possible to reduce the increase in the length of the transition portion 122 due to the height of the protrusion 117.

[0043] The magnetic members are positioned on the flanges 116 of the first bobbin 111 and the second bobbin 112, and protrusions 117 are arranged around the magnetic members, thereby preventing lateral displacement of the magnetic members on the flanges 116 (116a, 114a) of the first bobbin 111 and the flanges 116 (116b, 114b) of the second bobbin 112. This facilitates stable assembly of the coil device 100.

[0044] (Terminal Portion) As shown in FIG. 9 , the coil component 100 has a terminal portion 150. Both ends of the winding 120 are electrically connected to and mounted on an electronic board (not shown) by the terminal portion 150. An example of a method for mounting the winding 120 on an electronic board is to directly solder the winding 120 to the electronic board. Specifically, the terminal portion 150 is configured as follows. The terminal portion 150 has a mounting base 151, which is disposed below the coil component and parallel to the flange portion 116. Both ends of the winding 120 are drawn from the winding shaft portion 113 of the first bobbin 111 or the second bobbin 112 to the lower side of the flange portion 116, and then pass through the mounting base 151 and are drawn to the lower side of the mounting base 151. The mounting base 151 and the coil component 100 are fixed together by a sealing material such as a resin, which will be described later. Both ends of the winding 120 are arranged parallel to each other, and are mounted on the electronic board by soldering or the like as rod-shaped terminals 152. Alternatively, the drawn-out tip of the winding 120 can be extended so that it forms a surface parallel to the mounting base 151, and the extended surface can be mounted on the electronic board by soldering or the like as a surface-mounted terminal 152. The mounting method on the electronic board is not limited to connecting the winding 120 to the electronic board as the terminal 152. For example, the coil component 100 can be provided with binding terminals electrically connected to the mounting terminals, and the winding 120 can be electrically connected to the binding terminals by binding both ends of the winding 120 to the corresponding binding terminals. The mounting terminals are joined to the electronic board by soldering or the like.

[0045] The coil bobbin 10 according to this embodiment can also be provided as two bobbins 110 (first bobbin 111 and second bobbin 112) without including the winding 120 or the core 140. As described above, the coil bobbin 10 according to this embodiment includes two bobbins 110 (first bobbin 111 and second bobbin 112). The bobbin 110 has a protruding region at one end of the bobbin 110 that extends in the circumferential direction of the winding shaft portion 113 around which the winding 120 is wound. The protruding region is provided with a recessed portion 115 that is recessed from the outer periphery toward the winding shaft portion 113 of the bobbin. The bobbin 110 has a concave-convex engaging portion 118. When the two bobbins 110 (first bobbin 111 and second bobbin 112) are arranged side by side with their axial directions aligned, and the recessed portions 115 are facing inward with respect to the space between the two bobbins 110, the concave-convex engaging portions 118 engage with each other.

[0046] The coil bobbin 10 can be easily manufactured by winding the winding 120 therearound using a method for manufacturing the coil bobbin 10, which will be described later. Specifically, by passing the winding 120 through the recess 115 in the winding process, the position of the winding 120 from the first bobbin 111 to the second bobbin 112 can be determined within a certain range. This prevents the winding 120 from shifting laterally during the folding process in which the first bobbin 111 and the second bobbin 112 are folded side-by-side. Furthermore, providing the protruding region prevents the winding 120 from loosening from the protruding region toward the opposite side of the winding shaft 113. Furthermore, the concave-convex engaging portion 118 prevents the first bobbin 111 and the second bobbin 112 from shifting laterally in the folded state, facilitating the assembly of the coil device 100.

[0047] (Method of Manufacturing Coil Bobbin) Next, an outline of a method of manufacturing the above-mentioned coil bobbin 10 will be described. The coil bobbin 10 has a winding 120 and a first bobbin 111 and a second bobbin 112 arranged side by side, each having a winding shaft portion 113 around which the winding 120 is wound. The method of manufacturing the coil bobbin 10 includes a winding process and a folding process. In the winding process, the first bobbin 111 and the second bobbin 112 are arranged vertically so that the winding shaft portions 113 are aligned in a substantially straight line, and the winding 120 is wound continuously across the winding shaft portion 113 of the first bobbin 111 and the winding shaft portion 113 of the second bobbin 112. In the folding process, the first bobbin 111 and the second bobbin 112 are folded and arranged side by side, with a crossover portion 122, which is a length region of the winding 120 that straddles the first bobbin 111 and the second bobbin 112, facing inward.

[0048] Next, a detailed description will be given of the manufacturing method of the coil bobbin 10. As described above, the first bobbin 111 and the second bobbin 112 have a protruding region extending in the circumferential direction of the winding shaft portion 113 at at least one end, and the protruding region has a recessed portion 115 formed in a concave shape extending from the outer circumferential edge of the protruding region toward the winding shaft portion 113. The protruding region is provided at one end on the side where the first bobbin 111 and the second bobbin 112 abut.

[0049] 7 and 8 , in the winding process, first bobbin 111 and second bobbin 112 abut one end thereof, and first bobbin 111 and second bobbin 112 are linearly arranged so that recesses 115 of first bobbin 111 and second bobbin 112 are located on the same circumferential side of winding shaft portion 113. Here, "the recesses 115 of first bobbin 111 and second bobbin 112 are located on the same circumferential side of winding shaft portion 113" means that the opening directions of recesses 115 of first bobbin 111 and second bobbin 112 are substantially the same. Specifically, when first bobbin 111 and second bobbin 112 are viewed from either lateral direction perpendicular to the winding axis direction in the expanded state of first bobbin 111 and second bobbin 112, the openings of recesses 115 of first bobbin 111 and second bobbin 112 can be seen at once. Preferably, the recesses 115 of the first bobbin 111 and the second bobbin 112 are in communication with each other. That is, when viewed in the axial direction of the first bobbin 111 and the second bobbin 112, the recesses 115 of the first bobbin 111 and the recesses 115 of the second bobbin 112 at least partially overlap. When the recesses of the first bobbin 111 and the second bobbin 112 are in communication with each other, the distance between the recesses 115 of the first bobbin 111 and the recesses 115 of the second bobbin 112 can be made shorter than when the recesses are not in communication, thereby shortening the length of the slack portion 121. When the winding 120 is thinner than the height of the protrusion 117, the recesses 115 of the first bobbin 111 and the second bobbin 112 do not have to be in communication with each other in the folded state, and may be shifted circumferentially or radially.

[0050] 8 , in the winding process of the winding 120, the transition portion 122 is passed through the recesses 115 of the first bobbin 111 and the second bobbin 112, and the winding 120 is wound continuously across the winding shaft portion 113 of the first bobbin 111 and the winding shaft portion 113 of the second bobbin 112. Specifically, the winding 120 is wound, for example, from one end (the left end in FIG. 8 ) of the first bobbin 111 to the other end (the right end in FIG. 8 ) and passes through the recesses 115 of the first bobbin 111 to cross from the first bobbin 111 to the second bobbin 112. The winding 120 then passes through the recesses 115 of the second bobbin 112 and is wound continuously across the second bobbin 112 from one end (the left end in FIG. 8 ) to the other end (the right end in FIG. 8 ). Here, the crossover portion 122 of the winding 120 refers to the length of the winding 120 sandwiched between the winding 120 wound around the first winding shaft portion 113 a and the winding 120 wound around the second winding shaft portion 113 b. In this embodiment, the crossover portion 122 is the length of the winding 120 spanning from the recess 115 of the first bobbin 111 to the recess 115 of the second bobbin 112.

[0051] In the folding process, the first bobbin 111 and the second bobbin 112 are folded so that the transition portion 122 faces inward, that is, so that the recesses 115 of the first bobbin 111 and the second bobbin 112 face inward. At this time, the first bobbin 111 and the second bobbin 112, which were arranged in a substantially linear manner, are rotated by approximately 180 degrees without being twisted until they are arranged side by side with their axial directions aligned with each other.

[0052] When the coil bobbin 10 is folded, the above-described multiple magnetic members are inserted or positioned, and the above-described terminal portion 150 is provided. As shown in FIG. 2, the winding 120 may protrude outward beyond the outer surface 116c of the flange 116 through the recess 115 (see FIG. 1). In this case, the winding 120 protruding beyond the outer surface 116c of the flange 116 may prevent stable contact between the I-core 143 and the outer surface 116c of the flange 116, which may result in poor adhesion between the I-core 143 and the flange 116. To avoid this, it is recommended to push the winding 120 protruding outward beyond the outer surface 116c of the flange 116 toward the winding shaft portion 113, and position the I-core 143 so that the winding 120 does not protrude above the outer surface 116c of the flange 116, as shown in FIG. 4. The I-core 143, which is a magnetic member, may be fixed to the flange 116 with an adhesive. Alternatively, the mounting base 151 and the U-core 142 may be fixed to the coil bobbin 10 with an adhesive. Furthermore, the portions other than the terminals 152 may be covered with a sealing material such as epoxy resin or polyester resin. Both ends of the winding 120 are electrically connected to the electronic board as described above.

[0053] Here, when attempting to wind the winding 120 onto the first bobbin 111 with the first bobbin 111 and the second bobbin 112 arranged side by side, the wire supply unit of the winding device is likely to interfere with the second bobbin 112, which is located radially adjacent to the first bobbin 111. For this reason, in order to wind the winding 120 with the first bobbin 111 and the second bobbin 112 located close to each other, it is necessary to wind the winding while avoiding interference between the second bobbin 112 and the wire supply unit, which reduces the efficiency of the winding process of the winding 120. When winding the winding 120 onto the first bobbin 111 with the winding shaft units 113 of the first bobbin 111 and the second bobbin 112 arranged linearly, the second bobbin 112 is not located radially of the first bobbin 111, so interference between the second bobbin 112 and the wire supply unit is prevented. This allows the winding 120 to be wound continuously from the first bobbin 111 to the second bobbin 112, thereby improving the efficiency of the winding process of the winding 120. Furthermore, after the winding 120 is wound, the first bobbin 111 and the second bobbin 112 are folded and placed side by side so that the gap between the first bobbin 111 and the second bobbin 112 can be freely adjusted. In other words, the gap between the first bobbin 111 and the second bobbin 112 can be reduced to make the coil bobbin 10 more compact. Furthermore, when attempting to wind the winding 120 sequentially around the first bobbin 111 and the second bobbin 112 with the first bobbin 111 and the second bobbin 112 arranged side by side, it is necessary to switch the winding direction between the first bobbin 111 and the second bobbin 112. In other words, it is necessary to wind the winding 120 in opposite directions around the first winding shaft portion 113a and the second winding shaft portion 113b. This is because the winding 120 is wound in the same direction as the direction of the magnetic lines of force passing through the closed magnetic path formed by the magnetic member. On the other hand, when the winding 120 is wound with the first bobbin 111 and the second bobbin 112 in the unfolded state, the winding 120 is wound in the same direction when winding the winding 120 around the first bobbin 111 and when winding the winding 120 around the second bobbin 112, and there is no need to switch the winding direction. Furthermore, by folding the first bobbin 111 and the second bobbin 112, the winding directions of the winding 120 around the first winding shaft portion 113a and the second winding shaft portion 113b naturally become opposite to each other.Since there is no need to change the winding direction of the winding 120 in this way, the efficiency of the winding process can be improved.

[0054] By providing recesses 115 at the ends of the first bobbin 111 and the second bobbin 112 that abut in the unfolded state, it is possible to determine within a certain range the position of the winding 120 that spans the first bobbin 111 and the second bobbin 112. This makes it possible to prevent the winding 120 from shifting sideways during the folding process, and to maintain a constant folding position of the winding 120 in the manufactured coil bobbin 10.

[0055] The present invention is not limited to the above-described embodiment and includes various modifications, improvements, and the like as long as the object of the present invention is achieved. In the first embodiment, the first bobbin 111 and the second bobbin 112 may not have protruding regions such as the flanges 116. In this case, the winding 120 passes between the first bobbin 111 and the second bobbin 112 from any location on the first bobbin 111 and the second bobbin 112. The coil bobbin 10 may include three or more bobbins 110. That is, in the winding process, three or more bobbins 110 may be arranged in a straight line and the winding 120 may be wound continuously around them, and in the folding process, the bobbins may be folded at two or more locations so that the crossover portions 122 are on the inside. For example, when the winding 120 is wound around three bobbins 110, the three bobbins 110 are folded so as to be arranged in a triangle, and when the winding 120 is wound around four bobbins 110, the four bobbins are folded so as to be arranged in a square. This allows the winding 120 to be wound around all sides of the polygonal closed magnetic circuit. The winding 120 may be wound around the bobbin 110 in multiple layers. By winding the winding 120 in an odd number of layers, such as three or five layers, both ends of the winding 120 can be arranged at the lower end of the coil bobbin 10 to form terminal portions 150, and the winding 120 can be passed from the first bobbin 111 to the second bobbin 112 at the upper end of the coil bobbin 10. Furthermore, multiple windings 120 may be wound around the bobbin 110. In this case, the multiple windings 120 may be wound in an overlapping manner, or may be wound at different positions in the winding axis direction of the winding shaft portion 113. In other words, the winding positions on the winding shaft portion 113 may be divided for each winding 120. In this case, in order to separate the winding positions of the windings 120, a flange may be provided midway along the length of the winding shaft portion 113, with one winding 120 wound on one side of the flange and another winding 120 wound on the other side of the flange. A concave-convex engaging portion 118 may be formed on this flange.

[0056] The above embodiments encompass the following technical concepts: (1) A coil bobbin including a winding and a first bobbin and a second bobbin arranged side by side with their axial directions aligned with each other, wherein the winding is wound continuously across the first bobbin and the second bobbin and is passed from the first bobbin to the second bobbin through an inner space sandwiched between the side by side first and second bobbins, and wherein the inner space has a slack portion. (2) The first bobbin and the second bobbin each have a winding shaft portion around which the winding is wound, and a protruding region extending in the circumferential direction of the winding shaft portion at one end of the first bobbin and the second bobbin, wherein the protruding region has a recess formed in a concave shape extending from an outer circumferential edge of the protruding region toward the winding shaft portion, and the first bobbin and the second bobbin are arranged so that at least a portion of each recess is located inside the space sandwiched between the first bobbin and the second bobbin. (3) The coil bobbin according to (2), wherein the slack portion has a length that allows the winding to pass through the recess and span between the first bobbin and the second bobbin when the first bobbin and the second bobbin are linearly arranged with their ends, on which the protrusion regions are provided, abutting against each other. (4) The coil bobbin according to (3), wherein the length of the slack portion is equal to or greater than the sum of the height of a bottom of the recess from the circumferential surface of the winding shaft portion of the first bobbin, the height of the bottom of the recess of the second bobbin, and the distance from the recess of the first bobbin to the recess of the second bobbin when the first bobbin and the second bobbin are linearly arranged with their ends, on which the protrusion regions are provided, abutting against each other. (5) The coil bobbin according to any one of (2) to (4), characterized in that the protruding region is a flange portion that protrudes from the winding shaft portion of the first bobbin or the second bobbin in a direction intersecting the axial direction, and the winding is passed from the first bobbin to the second bobbin on the winding shaft portion side of the flange portion. (6) The coil bobbin according to (1) to (5), wherein the first bobbin and the second bobbin have concave-convex engaging portions that engage with each other when arranged side by side so that their axial directions are aligned with each other.(7) A coil component comprising the coil bobbin according to any one of (1) to (6) and a core having magnetic legs inserted through each of the first bobbin and the second bobbin in the winding axis direction of the winding and configured by combining a plurality of magnetic members, wherein the first bobbin and the second bobbin have a winding shaft portion around which the winding is wound and a flange portion formed on one end and the other end of the first bobbin and the second bobbin, respectively, protruding from the winding shaft portion in a direction intersecting with the axial direction, wherein the flange portion at the one end or the flange portion at the other end of each of the first bobbin and the second bobbin has a protrusion on an outer surface opposite to the winding shaft portion, and at least one of the magnetic members is disposed across the flange portion of the first bobbin and the flange portion of the second bobbin, and the protrusion is disposed around the magnetic member. (8) A coil bobbin including two bobbins, wherein the bobbins have a protruding region at one end of the bobbin that extends in the circumferential direction of a winding shaft portion on which a winding is wound, and the protruding region has a recess formed in a concave shape that extends from the outer peripheral edge toward the winding shaft portion of the bobbin, and the bobbins are arranged side by side with their axial directions aligned with each other, and have concave-convex engaging portions that engage with each other when the two bobbins are arranged side by side with their axial directions aligned with each other and the recesses are facing inward with respect to the space sandwiched between the two bobbins. (9) A method for manufacturing a coil bobbin having a winding and a first bobbin and a second bobbin arranged side by side, each having a winding shaft portion around which the winding is wound, the method including: a winding process in which the first bobbin and the second bobbin are arranged vertically so that the winding shaft portions are aligned in a substantially straight line, and the winding is wound continuously across the winding shaft portion of the first bobbin and the winding shaft portion of the second bobbin; and a folding process in which the first bobbin and the second bobbin are folded and arranged side by side, with a crossover portion, which is a length region of the winding that spans the first bobbin and the second bobbin, facing inward.(10) The method for manufacturing a coil bobbin according to (9), wherein the first bobbin and the second bobbin have, at least at one end, a protruding region extending in the circumferential direction of the winding shaft portion, the protruding region having a recess formed in a concave shape extending from the outer circumferential edge of the protruding region toward the winding shaft portion, and in the winding process, the one end portions are abutted against each other and the first bobbin and the second bobbin are linearly arranged so that the recesses are located on the same circumferential side of the winding shaft portion, and the winding is wound continuously across the winding shaft portion of the first bobbin and the winding shaft portion of the second bobbin by passing the bridge portion through the recesses of the first bobbin and the second bobbin.

Claims

1. a winding, and a first bobbin and a second bobbin arranged side by side so that their axial directions are aligned with each other; The winding comprises: The wire is wound continuously around the first bobbin and the second bobbin, The wire is passed from the first bobbin to the second bobbin through an inner space between the first and second bobbins arranged side by side, A coil bobbin having a slack portion in the inner space.

2. The first bobbin and the second bobbin are a winding shaft portion around which the winding is wound; a protruding region extending in a circumferential direction of the winding shaft portion at one end of the first bobbin and the second bobbin, The protruding region is a recess formed in a concave shape extending from an outer circumferential edge of the protruding region toward the winding shaft portion, The first bobbin and the second bobbin, 2. The coil bobbin according to claim 1, wherein at least a portion of each of the recesses is disposed on an inner side between the first bobbin and the second bobbin.

3. The slack portion is 3. The coil bobbin according to claim 2, wherein when the first bobbin and the second bobbin are arranged in a straight line with their ends on which the protrusion region is provided abutting each other, the winding has a length that enables it to pass through the recess and span from the first bobbin to the second bobbin.

4. The length of the slack portion is 4. The coil bobbin according to claim 3, characterized in that the height of a bottom of the recess from a peripheral surface of the winding shaft portion in the first bobbin, the height of the bottom of the recess in the second bobbin, and the distance from the recess of the first bobbin to the recess of the second bobbin when the first bobbin and the second bobbin are arranged in a straight line with their ends having the protrusion region abutting each other.

5. The protruding region is a flange portion protruding from the winding shaft portion of the first bobbin or the second bobbin in a direction intersecting the axial direction, The winding comprises:

5. The coil bobbin according to claim 2, wherein the first bobbin is connected to the second bobbin on a side closer to the winding shaft portion than an outer surface of the flange portion.

6. The first bobbin and the second bobbin are The recessed and protruding engaging portions are arranged side by side so that the axial directions are aligned with each other, and engage with each other. The concave-convex engagement portion is a combination of at least a pair of engagement protrusions and an engagement recess having a concave shape corresponding to the engagement protrusions, 5. The coil bobbin according to claim 1, wherein the engaging protrusion has a shape that becomes monotonically narrower in a protruding direction of the engaging protrusion as viewed in the axial direction.

7. A coil bobbin according to any one of claims 1 to 4, a core having magnetic legs inserted in the first bobbin and the second bobbin in a winding axis direction of the winding, the core being configured by combining a plurality of magnetic members, The first bobbin and the second bobbin are a winding shaft portion around which the winding is wound; a flange portion formed at one end and the other end of the first bobbin and protruding from the winding shaft portion in a direction intersecting with the axial direction, The flange portion at the one end portion or the flange portion at the other end portion of each of the first bobbin and the second bobbin is a protrusion on an outer surface opposite to the winding shaft portion, At least one of the magnetic members is the protrusion is disposed across the flange portion of the first bobbin and the flange portion of the second bobbin, and the protrusion is disposed around the magnetic member, A coil component, wherein the protrusion provided on the flange portion of the first bobbin and the protrusion provided on the flange portion of the second bobbin are spaced apart from each other in a direction in which the first bobbin and the second bobbin are arranged horizontally.

8. A coil bobbin including two bobbins, The bobbin is a protruding region extending in a circumferential direction of a winding shaft portion around which a winding is wound is provided at one end of the bobbin; The protruding region includes: a recess formed in a concave shape extending from an outer circumferential edge toward the winding shaft portion of the bobbin, The bobbin is A coil bobbin characterized in that two of the bobbins are arranged side by side with their axial directions aligned with each other, and the bobbins have a concave-convex engagement portion that engages with each other when the concave portions are facing inward toward the space sandwiched between the two bobbins.

9. A method for manufacturing a coil bobbin having a winding, and a first bobbin and a second bobbin arranged side by side, each of which has a winding shaft portion around which the winding is wound, comprising the steps of: a winding process in which the winding is wound continuously around the winding shaft portion of the first bobbin and the winding shaft portion of the second bobbin in a state in which the first bobbin and the second bobbin are vertically arranged such that the winding shaft portions are aligned in a substantially straight line; a folding process in which the first bobbin and the second bobbin are folded and arranged side by side with a transition portion, which is a length region of the winding that spans the first bobbin and the second bobbin, on the inside; A method for manufacturing a coil bobbin comprising the steps of:

10. The first bobbin and the second bobbin are a flange portion extending in a circumferential direction of the winding shaft portion at least at one end thereof; The flange portion is a recess formed in a concave shape extending from an outer circumferential edge of the flange portion toward the winding shaft portion, In the winding step, the first bobbin and the second bobbin are linearly arranged such that the one ends are in contact with each other and the recesses are located on the same circumferential side of the winding shaft portion, and the winding is wound continuously across the winding shaft portion of the first bobbin and the winding shaft portion of the second bobbin by passing the transition portion through the recesses of the first bobbin and the second bobbin, 10. The method for manufacturing a coil bobbin according to claim 9, wherein a length of the transition portion is a sum of a distance from a peripheral surface of the winding shaft portion of the first bobbin to a deepest portion of the recess, a distance from a peripheral surface of the winding shaft portion of the second bobbin to a deepest portion of the recess, and a distance between an inner surface of the flange portion of the first bobbin that abuts against the second bobbin and an inner surface of the flange portion of the second bobbin that abuts against the first bobbin when the first bobbin and the second bobbin are arranged vertically such that the winding shaft portions are aligned in a substantially straight line.

11. The first bobbin and the second bobbin are a flange portion extending in a circumferential direction of the winding shaft portion at at least one end portion in an axial direction of the winding shaft portion, The flange portion of each of the first bobbin and the second bobbin is a protrusion on an outer surface opposite to the winding shaft portion, In the winding step, the first bobbin and the second bobbin are vertically arranged so that the winding shaft portions are aligned in a substantially straight line, the protruding portion of the first bobbin abuts against the outer surface of the flange portion of the second bobbin, The method for manufacturing a coil bobbin according to claim 9 , wherein the protruding portion of the second bobbin abuts against the outer surface of the flange portion of the first bobbin.