JP7750693B2 - Coil Device - Google Patents

Description

The present invention relates to a coil device.

Known coil devices used in transformers and the like include those described in Patent Documents 1 and 2. The coil device described in Patent Document 1 is a vertical coil device in which the coil winding axis is perpendicular to the surface of the mounting board, while the coil device described in Patent Document 2 is a horizontal coil device in which the coil winding axis is parallel to the surface of the mounting board.

Vertical coil devices such as those described in Patent Document 1 have the problem that their height along the winding axis tends to be large, making it difficult to achieve a low profile. In contrast, horizontal coil devices such as those described in Patent Document 2 can avoid the above problems and are advantageous for achieving a low profile.

However, in the coil device described in Patent Document 2, a first terminal block is formed below a first flange formed at one axial end of the bobbin, and a second terminal block is formed below a second flange formed at the other axial end of the bobbin. This increases the size of the coil device in both the axial direction of the bobbin and the direction perpendicular thereto, making it difficult to achieve miniaturization.

JP 2014-36194 A JP 2018-67673 A

The present invention was made in light of these circumstances, and its purpose is to provide a coil device that can be made smaller.

In order to achieve the above object, a coil device according to the present invention comprises:
a bobbin having a winding core portion around which a wire is wound and a flange portion formed at an axial end of the winding core portion;
a terminal block formed separately from the bobbin and attached to the bobbin,
The terminal block is disposed at a position spaced apart from the outer peripheral surface of the winding core in a direction perpendicular to the axial direction of the winding core.

The coil device according to the present invention has a terminal block that is formed separately from the bobbin and attached to the bobbin. Therefore, when manufacturing the coil device, it is possible to wind wire around the outer surface of the winding core with the terminal block removed from the bobbin. This prevents the terminal block from interfering with the automatic winding, particularly when winding wire using an automatic winding machine. Furthermore, by forming the terminal block (only) from a highly heat-resistant resin, separate from the bobbin, a heat-resistant coil device can be realized at low cost.

In addition, in the coil device according to the present invention, the terminal block is positioned at a distance from the outer peripheral surface of the winding core in a direction perpendicular to the axial direction of the winding core. This allows the terminal block to be positioned to the side of the winding core, making it possible to reduce the size (length) of the coil device in the axial direction of the winding core compared to conventional technology in which the terminal block is formed at the axial end of the winding core. Also, compared to conventional technology in which the terminal block is formed below the flange, it is possible to reduce the size (height) of the coil device in the direction perpendicular to the axial direction of the winding core (height direction of the coil device). Therefore, the coil device according to the present invention can be made more compact.

Preferably, the terminal block is connected to one axial end of the winding core and the other axial end of the winding core, and is arranged approximately parallel to the axial direction of the winding core. This configuration prevents the terminal block from being arranged in an unnecessarily protruding state in a direction perpendicular to the axial direction of the winding core (to the side of the winding core), making it possible to reduce the size of the coil device in the direction perpendicular to the axial direction of the winding core.

Preferably, the terminal block has an arm portion that protrudes toward the bobbin and has a hook-shaped first hook portion formed at its tip, and the flange portion has a flange engagement portion that extends in a direction approximately perpendicular to the arm portion and engages with the first hook portion. By engaging the arm portion of the terminal block with the flange engagement portion of the flange portion via the first hook portion, it is possible to attach the terminal block to the bobbin with sufficient fixing strength without using adhesives or the like, thereby reducing costs and speeding up manufacturing. Furthermore, the terminal block can be positioned at a distance corresponding to the length of the arm portion from the outer surface of the winding core portion in a direction perpendicular to the axial direction of the winding core portion, and the position of the terminal block can be adjusted by appropriately changing the length of the arm portion.

Preferably, a hook-shaped second hook portion is formed at the tip of the flange engagement portion, and the lead-out portion of the wire is drawn out along the periphery of the arm portion toward the terminal block while the first hook portion is engaged with the flange engagement portion. By drawing the lead-out portion of the wire along the periphery of the arm portion toward the terminal block, it is possible to draw the lead-out portion over a short distance from the winding core portion to the terminal block, preventing unnecessary routing of the lead-out portion (increasing the wire length of the lead-out portion), improving the quality of the coil device, and contributing to reducing electrical resistance and suppressing wire resonance. Furthermore, by forming a second hook portion on the flange engagement portion, it is possible to prevent the lead-out portion drawn out along the periphery of the arm portion from shifting position toward the tip of the flange engagement portion.

Preferably, a terminal block fixing portion to which the terminal block is fixed is formed at the axial end of the bobbin, the terminal block fixing portion having a first step portion, the terminal block having a second step portion, and the first step portion and the second step portion engaging with each other when the first step undersurface of the first step portion and the second step undersurface of the second step portion are in contact. This configuration fixes the first step portion and the second step portion to each other, preventing misalignment of the terminal block relative to the terminal block fixing portion in the normal directions of the first step undersurface and the second step undersurface, and allowing the terminal block to be attached to the terminal block fixing portion with sufficient fixing strength.

Preferably, a terminal block fixing portion to which the terminal block is fixed is formed at the axial end of the bobbin, the terminal block fixing portion having a convex portion that protrudes toward the terminal block, and the terminal block having a concave portion that engages with the convex portion. Engaging the convex portion of the terminal block fixing portion with the concave portion of the terminal block prevents the terminal block from shifting in position relative to the terminal block fixing portion in the extension direction of the terminal block (axial direction of the winding core).

Preferably, the flange is formed along the circumferential direction of the winding core, and the flange has a notch through which the lead-out portion of the wire passes. This configuration makes it possible to pull out the lead-out portion of the wire wound around the winding core from the inside of the flange where the winding core is located to the outside via the notch, preventing unnecessary routing of the lead-out portion.

Preferably, one lead-out portion of the wire passes through the notch and is led out from the outside of the flange toward the terminal block, and the other lead-out portion of the wire is led out from the inside of the flange toward the terminal block without passing through the notch. With this configuration, one lead-out portion of the wire passes outside the flange and the other lead-out portion passes inside the flange, thereby achieving good insulation between the one lead-out portion and the other lead-out portion via the flange.

Preferably, the terminal block further includes a cover portion disposed around the terminal block, the wire being made up of multiple wires, and multiple terminals, to which the lead-out portions of the multiple wires are respectively connected, attached to the terminal block along the axial direction of the winding core portion, the cover portion having a gripping portion for gripping the terminal block, a bottom portion disposed below the multiple terminals, and side portions extending from the side edges of the bottom portion. Gripping the terminal block with the gripping portion allows the cover portion to be attached to the terminal block with sufficient fixing strength without the use of adhesives, etc., thereby reducing costs and speeding up manufacturing. Furthermore, by providing the cover portion with a bottom portion and side portions, the terminals attached to the terminal block can be protected from external forces, etc., and the terminals and core can be well insulated via the bottom portion and side portions.

Preferably, the axial direction of the winding core portion is approximately parallel to the mounting surface. This configuration makes it possible to reduce the height of the coil device, thereby achieving a low-profile coil device.

Preferably, the coil further includes a case that houses the bobbin, the case being capable of being filled with potting resin, and at least one through-hole formed in the outer peripheral surface of the winding core. This configuration allows heat generated in the bobbin, etc., to be dissipated to the outside via the case and potting resin, allowing for efficient cooling of the coil device. Furthermore, by forming through-holes in the bobbin, it is possible for the potting resin to flow inside and outside the bobbin via the through-holes, allowing the potting resin to reach every corner of the case.

FIG. 1 is a perspective view of a coil device according to a first embodiment of the present invention. FIG. 2 is a perspective view of the coil device shown in FIG. 1 with the case and resin omitted. FIG. 3 is an exploded perspective view of the coil device shown in FIG. 4A is a side view of the base portion of the core shown in FIG. 3 as viewed from the outside in the Y-axis direction. 4B is a side view of the center leg portion and the outer leg portion of the core shown in FIG. 3 as viewed from the inside in the Y-axis direction. FIG. 5 is a cross-sectional view of the coil device shown in FIG. 1 taken along line VV. FIG. 6 is a perspective view of the bobbin shown in FIG. FIG. 7 is a side view of the bobbin shown in FIG. 6 on which the first coil portion and the second coil portion shown in FIG. 3 are mounted. FIG. 8 is a perspective view showing the terminal, terminal block, and cover portion shown in FIG. 9 is a perspective view of the bobbin shown in FIG. 6 to which the terminal block and cover shown in FIG. 8 are attached. FIG. 10 is a perspective view showing the configuration of the connection portion between the terminal block and the bobbin shown in FIG. FIG. 11 is a perspective view of a coil device according to a second embodiment of the present invention. FIG. 12 is an exploded perspective view of the coil device shown in FIG.

The present invention will now be described based on the embodiments shown in the drawings.

First Embodiment A coil device 10 according to this embodiment shown in FIG. 1 functions as, for example, a transformer and is used, for example, in an on-board charger for an EV (Electric Vehicle), a PHV (Plug-in Hybrid Vehicle), or a commuter vehicle, a power supply circuit for home or industrial electrical equipment, or a power supply circuit for computer equipment. The detailed configuration of the coil device 10 will be described below. In the following description, the positive Z-axis direction is referred to as the upper side, and the negative Z-axis direction is referred to as the lower side. Furthermore, the side toward the center of the coil device 10 is referred to as the inside or inner side, and the side away from the center of the coil device 10 is referred to as the outside or outer side.

As shown in FIG. 3, the coil device 10 includes a bobbin 20, a first coil portion 41 and a second coil portion 42, cores 50a and 50b, first terminals 61_1 and 61_2, second terminals 62_1 and 62_2, a terminal block 70, a cover portion 80, and a case 90. The coil device 10 is a horizontal coil device in which the winding axes of the first coil portion 41 and the second coil portion 42 are parallel to the surface of the mounting board (not shown). The mounting board is disposed above the coil device 10 shown in FIG. 1 (on the positive Z-axis side), and the top of the coil device 10 is the installation surface (mounting surface) of the coil device relative to the mounting board.

The case 90 is made of a metal with excellent cooling properties, such as aluminum, and has a case bottom 91 and case sides 92. The top of the case 90 is open, allowing the bobbin 20 and other items to be stored through an opening formed at the top of the case 90. The case bottom 91 has a roughly rectangular shape and forms the bottom surface of the case 90. The case sides 92 have a roughly square cylindrical shape overall and are formed along the outer edge of the case bottom 91.

More specifically, the case side portions 91 extend upward from each of the four sides that make up the outer edge of the case bottom portion 91. The case 90 is formed by bending a single metal plate or the like, and the mating surfaces of the bent portions of the case side portions 92 form joints 93. Note that the joints 93 may be sealed liquid-tight by applying an adhesive or the like to the joints 93.

The storage space formed by the case bottom 91 and case side 92 can accommodate the bobbin 20 and other components, and can be filled with potting resin 100, as shown in Figure 1. Potting resin 100 is made of silicone resin, urethane resin, epoxy resin, etc. The potting resin 100 is filled up to the opening of the case 90, and from the top surface of the hardened potting resin 100, part of the bobbin 20, parts of the first terminal 61_1, etc., and part of the cover 80 are exposed.

In this embodiment, heat generated by the bobbin 20 and other components can be dissipated to the outside via the case 90 and potting resin 100, allowing for efficient cooling of the coil device 10.

As shown in FIG. 3, the first coil portion 41 is formed by winding a first wire 41c around the outer peripheral surface of the winding core portion 21 of the bobbin 20. The second coil portion 42 is formed by winding a second wire 42c around the outer peripheral surface of the winding core portion 21 of the bobbin 20. The first wire 41c and the second wire 42c are wound around the outer peripheral surface of the winding core portion 21 using, for example, an automatic winding machine.

The first coil portion 41 is formed in two layers in a direction (radial direction) perpendicular to its winding axis, and the second coil portion 42 is formed in two layers in a direction (radial direction) perpendicular to its winding axis. The winding axes of the first coil portion 41 and the second coil portion 42 are approximately aligned and correspond to the Y-axis direction.

The first coil portion 41 is provided on one side of the winding core portion 21 in the Y-axis direction (positive Y-axis side), and the second coil portion 42 is provided on the other side of the winding core portion 21 in the Y-axis direction (negative Y-axis side). Either the first coil portion 41 or the second coil portion 42 constitutes a primary coil, and the other of the first coil portion 41 and the second coil portion 42 constitutes a secondary coil. The primary coil and secondary coil on the winding core portion 21 may be arranged on either one side or the other side of the winding core portion 21 in the Y-axis direction.

The first wire 41c and the second wire 42c are each made of an insulating wire, such as a copper wire. The first wire 41c and the second wire 42c may each be made of a solid wire or a twisted wire. The wire diameter (diameter) of the first wire 41c and the second wire 42c is preferably, for example, 1.0 to 3.0 mm. The wire diameters of the first wire 41c and the second wire 42c may be the same or different. For example, the wire diameter of the first wire 41c or the second wire 42c through which a larger current flows may be made thicker than the wire diameter of the other wire.

A lead portion 41a is formed at one end of the first coil portion 41, and a lead portion 41b is formed at the other end of the first coil portion 41. For example, the lead portion 41a is drawn out from the second layer of the first coil portion 41, and the lead portion 41b is drawn out from the first layer of the first coil portion 41.

In addition, a lead portion 42a is formed at one end of the second coil portion 42, and a lead portion 42b is formed at the other end of the second coil portion 42. For example, the lead portion 42a is drawn out from the second layer of the second coil portion 42, and the lead portion 42b is drawn out from the first layer of the second coil portion 42.

Core 50a and core 50b are so-called E-shaped cores and are attached to bobbin 20. Cores 50a and 50b can be made of, but are not limited to, magnetic materials such as metal and ferrite. Core 50a and core 50b each have the same shape. Core 50a has a base portion 51a, a pair of outer legs 52a, and a center leg portion 53a. Core 50b has a base portion 51b, a pair of outer legs 52b, and a center leg portion 53b. The following describes the configuration of core 50a, but the description of core 50a also applies to core 50b. Therefore, unless specifically necessary, a description of the configuration of core 50b will be omitted.

The base portion 51a has a predetermined thickness in the Y-axis direction, and as shown in Figures 4A and 4B, has predetermined lengths in both the X-axis and Z-axis directions. Hereinafter, the outer surface of the base portion 51a in the Y-axis direction will be referred to as the outer surface 510a, the inner surface of the base portion 51a in the Y-axis direction will be referred to as the inner surface 511a, the upper surface of the base portion 51a will be referred to as the upper surface 512a, and the lower surface of the base portion 51b will be referred to as the outer surface 510b, the inner surface of the base portion 51b in the Y-axis direction will be referred to as the inner surface 511b, the upper surface of the base portion 51b will be referred to as the upper surface 512b, and the lower surface of the base portion 51b will be referred to as the lower surface 513b.

The upper surface 512a and the lower surface 513a are surfaces that are perpendicular to the outer surface 510a and the inner surface 511a. The upper surface 512b and the lower surface 513b are surfaces that are perpendicular to the outer surface 510b and the inner surface 511b.

In this embodiment, an upper recess 54a is formed on the upper surface 512a of the base portion 51a, recessed at the position of the middle leg portion 53a. The upper recess 54a is formed in approximately the center of the base portion 51a in the X-axis direction, and has predetermined widths in the X-axis and Y-axis directions. The width of the upper recess 54a in the X-axis direction is approximately equal to the width of the middle leg portion 53a in the X-axis direction. The width of the upper recess 54a in the Y-axis direction is approximately equal to the thickness of the base portion 51a in the Y-axis direction (see Figure 3).

The upper recess 54a is recessed downward from the upper surface 512a to a predetermined depth, and the upper bottom surface 540a, which is the bottom surface of the upper recess 54a, is formed at approximately the same height as the upper portion of the outer periphery of the middle leg 53a. The upper bottom surface 540a is formed of a surface that is convexly curved upward, and the degree of curvature of the upper bottom surface 540a is approximately the same as the degree of curvature of the upper portion of the outer periphery of the middle leg 53a. Therefore, the upper bottom surface 540a is connected along the Y-axis direction so as to be approximately flush with the upper portion of the outer periphery of the middle leg 53a (see Figure 3).

Upper tapered surfaces 541a are formed on the inner wall surfaces of the upper recess 54a (surfaces raised from both sides of the upper bottom surface 540a in the X-axis direction). The upper tapered surfaces 541a are inclined at a predetermined angle and connect the upper surface 512a and the upper bottom surface 540a.

A lower recess 55a is formed on the underside 513a of the base portion 51a, recessed at the position of the middle leg portion 53a. The lower recess 55a is formed approximately in the center of the base portion 51a in the X-axis direction, and has a predetermined width in the X-axis and Y-axis directions. The width of the lower recess 55a in the X-axis direction is smaller than the width of the middle leg portion 53a in the X-axis direction, and is approximately equal to the width of the concave bottom portion 37a or 37b (Figure 6) of the bobbin 20 in the X-axis direction. The width of the lower recess 55a in the Y-axis direction is approximately equal to the thickness of the base portion 51a in the Y-axis direction.

As shown in FIG. 4B, the lower recess 55a is recessed upward from the lower surface 513a by a predetermined depth, and the depth of the lower recess 55a is greater than the depth of the upper recess 54a. The lower bottom surface 550a, which is the bottom surface of the lower recess 55a, is formed at a position spaced a predetermined distance below the lower portion of the outer peripheral surface of the middle leg 53a. The lower bottom surface 550a is a substantially flat surface, and a step is formed between the lower bottom surface 550a and the lower portion of the outer peripheral surface of the middle leg 53a.

A lower tapered surface 551a is formed on the inner wall surface of the lower recess 55a (surfaces raised from both sides of the lower bottom surface 550a in the X-axis direction). The lower tapered surface 551a is inclined at a predetermined angle and connects the lower surface 513a and the lower bottom surface 550a. The shape of the lower recess 55a roughly matches the shape of the recessed bottom 37a or 37b (Figure 6) of the bobbin 20.

In this embodiment, as shown in FIG. 3, the inside of the case 90 is filled with potting resin 100, and a resin layer made of potting resin 100 is formed around the cores 50a and 50b. In this case, the potting resin 100 penetrates into the upper recess 54a and the lower recess 55a shown in FIG. 4B, ensuring a sufficient contact area between the potting resin 100 and the cores 50a and 50b, and allowing heat generated in the cores 50a and 50b to be sufficiently dissipated via the potting resin 100.

Furthermore, by providing the upper recess 54a with an upper tapered surface 541a and the lower recess 55a with a lower tapered surface 551a, the surface area of the inner wall surfaces of the upper recess 54a and the lower recess 55a can be increased, thereby increasing the contact area between the upper recess 54a and the lower recess 55a and the potting resin 100.

Furthermore, when filling the case 90 with potting resin 100, the potting resin 100 flows through the upper recess 54a and the lower recess 55a, for example, from the inside (outside) to the outside (inside) in the Y-axis direction of the base portion 51a (i.e., the upper recess 54a and the lower recess 55a function as flow paths for the potting resin 100), allowing the potting resin 100 to reach every corner of the case 90.

The middle leg 53a is positioned between the pair of outer leg portions 52a and is connected to the inner surface 511a of the base portion 51a. The middle leg 53a extends a predetermined length along the Y-axis direction from the inner surface 511a and is positioned inside a through hole 211 formed in the winding core portion 21 of the bobbin 20. The middle leg 53a of the core 50a and the middle leg 53b of the core 50b are positioned inside the through hole 211 with their respective tip ends butted together. A gap may be formed along the Y-axis direction between the tip end of the middle leg 53a and the tip end of the middle leg 53b.

As shown in FIG. 4B , the middle leg 53a is not formed at the center of the inner surface 511a of the base portion 51a, but is formed at a position offset upward (to one side in the Z-axis direction) from the center C1 of the inner surface 511a. The distance L1 between the center C2 of the middle leg 53a and the center C1 of the inner surface 511a of the base portion 51a (i.e., the offset in the Z-axis direction of the center C2 of the middle leg 53a from the center C1 of the inner surface 511a) may be determined based on the length L2 of the base portion 51a (outer leg 52a) along the Z-axis direction. The ratio L1/L2 of L1 to L2 is preferably 0 < L1/L2 < 1/4, and more preferably 0 < L1/L2 < 1/6. In this embodiment, as will be described later, the middle leg portion 53a is positioned above the center C1 of the inner surface 511a in order to ensure sufficient space below the inner surface 511a to form the thick portion 56a in the outer leg portion 52a.

The upper portion of the outer periphery of the middle leg 53a is located close to the upper surface 512a of the base 51a and is located lower than the upper surface 512a. The shape of the upper portion of the outer periphery of the middle leg 53a roughly matches the shape of the upper bottom surface 540a (Figure 4A) of the base 51a. The lower portion of the outer periphery of the middle leg 53a is located close to the lower bottom surface 550a of the lower recess 55a and is located higher than the lower bottom surface 550a. In other words, the middle leg 53a is located between the upper surface 512a and the lower recess 55a (lower bottom surface 550a) in the Z-axis direction.

As shown in FIG. 3, the pair of outer legs 52a are arranged at a predetermined interval along the X-axis direction and are connected to the inner surface 511a of the base portion 51a. One of the pair of outer legs 52a is arranged at one end of the inner surface 511a in the X-axis direction, and the other of the pair of outer legs 52a is arranged at the other end of the inner surface 511a in the X-axis direction.

The pair of outer legs 52a extend a predetermined length from the inner surface 511a along the Y-axis direction and are positioned outside the winding core 21 of the bobbin 20.

As shown in FIG. 4B, a thick portion 56a is formed at the end of each of the pair of outer legs 52a in the Z-axis direction. The thick portion 56a is formed at the lower end of the outer leg 52a (i.e., the end on the opposite side in the Z-axis direction from the positional deviation direction (upward) of the middle leg 53a described above).

The thickened portion 56a protrudes inward in the X-axis direction (the side where the center C1 of the inner surface 511a of the base portion 51a is located) and is formed to be thick in the X-axis direction. By forming the thickened portion 56a in the outer leg portion 52a, it is possible to ensure a sufficient cross-sectional area of the outer leg portion 52a, resulting in a coil device 10 with good inductance characteristics.

In addition, since the cross-sectional area of the outer leg 52a increases by the amount of the thickened portion 56a, even if the length of the outer leg 52a along the X-axis or Z-axis direction is reduced (i.e., the volume of the core 50a is reduced), it is possible to sufficiently secure the necessary cross-sectional area, thereby successfully achieving a reduction in the size of the core 50a and, in turn, the coil device 10. Furthermore, by reducing the size of the core 50a, for example, when filling the potting resin 100 around the core 50a, the potting resin 100 can be more easily introduced around the core 50a.

The width W1 of the thick portion 56a along the X-axis direction increases downward. The ratio W1/W2 of the width W1 of the thick portion 56a along the X-axis direction to the maximum width W2 of the base portion 51a along the X-axis direction is preferably 0 < W1/W2 < 1/2. Setting the value of W1/W2 within the above range ensures a sufficient volume for the thick portion 56a and also ensures a sufficient volume for the area where the thick portion 56a is not formed, contributing to improved inductance characteristics of the coil device 10.

The inner surface 520a of the outer leg 52a curves inward in the X-axis direction toward the lower end of the outer leg 52a. That is, because the thickened portion 56a is formed in the outer leg 52a, the inner surface 520a curves toward the center C1 of the inner surface 511a of the base portion 51a at the position of the thickened portion 56a. The curved portion of the inner surface 520a curves generally along the outer peripheral surface of the middle leg 53a. Also, as shown in FIG. 5, the curved portion of the inner surface 520a curves generally along the peripheral edge of the flange 22a (flange main body 220a) of the bobbin 20. The outer surface of the outer leg 52a, located on the opposite side of the inner surface 520a in the X-axis direction, extends along the Z-axis direction, and the shape of the inner surface 520a is different from that of the outer surface.

As shown in FIG. 4B, in this embodiment, the cross-sectional area S1 of the middle leg portion 53a is approximately equal to the sum of the cross-sectional areas S2 and S3 of one and the other of the pair of outer legs 52a. In this embodiment, the cross-sectional area of the outer leg portion 52a is increased as a result of forming the thick portion 56a in the outer leg portion 52a. Therefore, even if the overall size of the outer leg portion 52a is reduced, the sum of the cross-sectional areas of the pair of outer legs 52a (S2 + S3) can be made approximately equal to the cross-sectional area S1 of the middle leg portion 53a.

By forming a thick portion 56a on the outer leg portion 52a and using this configuration, it is possible to effectively prevent magnetic saturation of the magnetic flux passing through the middle leg portion 53a and the pair of outer legs 52a, thereby improving the inductance characteristics of the coil device 10.

The bobbin 20 is made of plastic, such as PPS, PET, PBT, or LCP, or other insulating material (preferably a heat-resistant material). As shown in Figure 3, the bobbin 20 has a winding core portion 21, flange portions 22a and 22b, and terminal block fixing portions 23a and 23b.

A first wire 41c and a second wire 42c are wound around the outer peripheral surface of the winding core 21 to form the first coil portion 41 and the second coil portion 42. The first coil portion 41 is positioned on one side of the winding core 21 in the Y-axis direction, between the flange 22a and protrusions 33 and 34 (Figure 7), which will be described later.

One end of the first coil portion 41 in the winding axis direction is located adjacent to the flange portion 22a, and the other end of the first coil portion 41 in the winding axis direction is located adjacent to the protrusions 33 and 34. One end of the second coil portion 42 in the winding axis direction is located adjacent to the flange portion 22b, and the other end of the second coil portion 42 in the winding axis direction is located adjacent to the protrusions 33 and 34.

The winding core 21 is a cylindrical body having a substantially elliptical shape, and the axial direction of the winding core 21 coincides with the Y-axis direction. A through hole 211 is formed inside the winding core 21, and the middle legs 53a and 53b of the cores 50a and 50b can be accommodated inside the through hole 211. As described above, the coil device 10 in this embodiment is a horizontal coil device, and therefore the axial direction of the winding core 21 is substantially parallel to the mounting surface of the coil device 10 or the mounting surface of the mounting board (not shown). This makes it possible to reduce the height of the coil device 10, thereby enabling the coil device 10 to have a low profile.

The cross-sectional shape of the winding core 21 (the cross-sectional shape of a surface parallel to the XZ plane) is approximately elliptical (see Figure 5). The long-side surfaces of the winding core 21 (the upper and lower portions of the outer circumferential surface of the winding core 21) are approximately flat, while the short-side surfaces of the winding core 21 (the side portions of the outer circumferential surface of the winding core 21) are curved. Note that the long-side surfaces of the winding core 21 may be curved, but the degree of curvature is preferably smaller than the degree of curvature of the short-side surfaces of the winding core 21.

As shown in FIG. 6 , through-holes 35a and 35b are formed at a predetermined interval in the Y-axis direction in the upper portion of the outer peripheral surface of winding core 21. Through-holes 35a and 35b are located in the center of winding core 21 in the X-axis direction. Through-hole 35a is located on one side of protrusion 33 in the Y-axis direction (where first coil 41 is located) and is located between flange 22a and protrusion 33 in the Y-axis direction. Through-hole 35b is located on the other side of protrusion 33 in the Y-axis direction (where second coil 42 is located) and is located between flange 22b and protrusion 33 in the Y-axis direction. Through-holes 35a and 35b each have the same shape and have a roughly elliptical opening with a long side in the Y-axis direction.

Through-holes 36a and 36b are formed at a predetermined interval in the Y-axis direction in the lower portion of the outer peripheral surface of the winding core 21. The through-holes 36a and 36b are located in the center of the winding core 21 in the X-axis direction. The through-hole 36a is located on one side of the protrusion 34 (Figure 7) in the Y-axis direction (where the first coil 41 is located) and is located between the flange 22a and the protrusion 34 in the Y-axis direction. The through-hole 36b is located on the other side of the protrusion 34 in the Y-axis direction (where the second coil 42 is located) and is located between the flange 22b and the protrusion 34 in the Y-axis direction. The through-holes 36a and 36b are identical in shape and have approximately elliptical openings with their long sides in the Y-axis direction. The position of the through-hole 36a corresponds to the position of the through-hole 35a in the Z-axis direction, and the position of the through-hole 36b corresponds to the position of the through-hole 35b.

By forming through-holes 35a, 35b, 36a, and 36b in the winding core 21, the potting resin 100 (Figure 1) can flow inside and outside the bobbin 20 (winding core 21) through these through-holes, allowing the potting resin 100 to reach every corner of the case 90.

Flange portion 22a is formed at one axial end of winding core portion 21, and flange portion 22b is formed at the other axial end of winding core portion 21. Flange portion 22a and flange portion 22b have the same shape. Flange portion 22a has a flange main body 220a that extends circumferentially along the outer surface of winding core portion 21 at one end of winding core portion 21 in the Y axis direction. Flange portion 22b has a flange main body 220b that extends circumferentially along the outer surface of winding core portion 21 at the other end of winding core portion 21 in the Y axis direction. Flange main body 220a is made of a plate with a predetermined thickness in the Y axis direction and protrudes outward in the radial direction of winding core portion 21. Flange main body 220b is made of a plate with a predetermined thickness in the Y axis direction and protrudes outward in the radial direction of winding core portion 21.

A pair of mounting portions 32a are formed below the flange body 220a (see Figure 5). One mounting portion 32a is formed on one side of the flange body 220a in the X-axis direction, and the other mounting portion 32a is formed on the other side of the flange body 220a in the X-axis direction. The one mounting portion 32a and the other mounting portion 32a are arranged at a predetermined distance in the X-axis direction. The pair of mounting portions 32a extend approximately parallel to the flange body 220a along the XZ plane, and the bottom surfaces of the pair of mounting portions 32a are approximately flat. The pair of mounting portions 32a are placed on the case bottom 91 of the case 90 shown in Figure 3.

A pair of mounting portions 32b are formed below the flange main body 220b. The configuration and function of the pair of mounting portions 32b are similar to those of the pair of mounting portions 32a, so a detailed description thereof will be omitted. The pair of mounting portions 32a and the pair of mounting portions 32b can support the winding core portion 21 of the bobbin 20, etc.

A concave bottom 37a is formed between each of the pair of mounting portions 32a, and a concave bottom 37b is formed between each of the pair of mounting portions 32b. The concave bottoms 37a and 37b are recessed upward from the bottom surfaces of the mounting portions 32a and 32b. The bottoms of the concave bottoms 37a and 37b form the outer peripheral surfaces of the flange bodies 220a and 220b, and portions of the inner wall surfaces of the concave bottoms 37a and 37b are tapered. By forming the recessed bottoms 37a and 37b in the flange bodies 220a and 220b, when the potting resin 100 (FIG. 1) is filled, the potting resin 100 flows through the recessed bottoms 37a and 37b, for example, from the inside (outside) to the outside (inside) in the Y-axis direction of the recessed bottoms 37a and 37b (i.e., the recessed bottoms 37a and 37b function as flow paths for the potting resin 100), allowing the potting resin 100 to spread particularly below the bobbin 20.

A flange engagement portion 24a is formed above the flange body 220a. The flange engagement portion 24a is integrally connected to the upper part of the flange body 220a and extends approximately parallel to the flange body 220a along the XZ plane. In other words, the flange engagement portion 24a has a shape that extends upward from the flange body 220a and constitutes part of the flange body 220a. The flange engagement portion 24a is formed on the upper end of the flange body 220a on the negative X-axis direction side, and protrudes above the fixed body portion 230a of the terminal block fixed portion 23a.

The flange engagement portion 24a has a predetermined thickness in the Y-axis direction and a surface that is approximately parallel to the XZ plane. The flange engagement portion 24a extends in a direction that is approximately perpendicular to the longitudinal direction (X-axis direction) of the arm portion 72a (Figure 8) of the terminal block 70 (described below). The terminal block hook portion 73a (Figure 8) formed at the tip of the arm portion 72a can be engaged with the flange engagement portion 24a.

A hook-shaped bobbin hook 25a is formed at the tip (upper end) of the flange engagement portion 24a. The bobbin hook 25a is configured to protrude inward in the X-axis direction and outward in the Z-axis direction from the upper end of the flange engagement portion 24a. More specifically, the bobbin hook 25a protrudes outward in the Y-axis direction beyond the outer surface of the flange engagement portion 24a in the Y-axis direction. The bobbin hook 25a also protrudes inward in the X-axis direction beyond the inner surface of the flange engagement portion 24a in the X-axis direction. The cross-sectional area of the bobbin hook 25a along the XY plane is larger than the cross-sectional area of the flange engagement portion 24a along the XY plane. The bobbin hook portion 25a has a function (locking function) of preventing the lead portion 41a or 41b of the first coil portion 41, which is pulled out along the periphery of the flange engagement portion 24a, from shifting position above the flange engagement portion 24a.

The configuration and function of the flange engagement portion 24b formed above the flange main body 220b and the bobbin hook portion 25b formed at the tip of the flange engagement portion 24b are similar to those of the flange engagement portion 24a and bobbin hook portion 25a described above, respectively, and therefore will not be described in detail. The bobbin hook portion 25b also has a function (locking function) of preventing the lead portion 42a or 42b of the second coil portion 42, which is pulled out along the periphery of the flange engagement portion 24b, from shifting position above the flange engagement portion 24b.

A terminal block fixing portion 23a is formed at one end of the bobbin 20 in the Y-axis direction, to which one end of the terminal block 70 (Figure 8) in the Y-axis direction is fixed, and a terminal block fixing portion 23b is formed at the other end of the bobbin 20 in the Y-axis direction, to which the other end of the terminal block 70 in the Y-axis direction is fixed. The terminal block fixing portions 23a and 23b not only function to fix the terminal block 70, but also serve to fix part of the automatic winding machine when the first wire 41c and second wire 42c are wound around the winding core 21 by the automatic winding machine.

The terminal block fixing portion 23a has a fixing main body portion 230a, a bobbin protrusion portion 30a, and a bobbin step portion 31a. The terminal block fixing portion 23b has a fixing main body portion 230b, a bobbin protrusion portion 30b, and a bobbin step portion 31b.

The fixed main bodies 230a and 230b are generally flat plate-shaped with surfaces generally parallel to the XY plane, and have a predetermined thickness in the Z-axis direction. The width of the fixed main bodies 230a and 230b along the X-axis direction is greater than the width of the winding core 21 along the X-axis direction, and is generally equal to the width of the flange main bodies 220a and 220b along the X-axis direction. The fixed main body 230a is integrally connected to the outer surface in the Y-axis direction of the flange main body 220a of the flange 22a, and protrudes outward in the Y-axis direction from that surface. The fixed main body 230b is integrally connected to the outer surface in the Y-axis direction of the flange main body 220b of the flange 22b, and protrudes outward in the Y-axis direction from that surface.

The bobbin protrusions 30a and 30b consist of protruding pieces with a protruding shape, and protrude a predetermined length outward in the X-axis direction from the side (side surface) of the fixed main body 230a and 230b, respectively. The protruding direction of the bobbin protrusions 30a and 30b corresponds to the direction in which the terminal block 70 is arranged.

The bobbin protrusions 30a and 30b have a flattened, approximately rectangular parallelepiped shape, and the thickness of the bobbin protrusions 30a and 30b in the Z-axis direction is smaller than the thickness of the fixed main bodies 230a and 230b in the Z-axis direction. The bobbin protrusion 30a engages with the terminal block recess 75a (Figure 8) of the terminal block 70, and the bobbin protrusion 30b engages with the terminal block recess 75b (Figure 8) of the terminal block 70.

The bobbin step portion 31a is formed on the back surface of the fixed main body portion 230a, at the corner where the end portion (side portion) of the fixed main body portion 230a on the negative X-axis side intersects with the end portion on the positive Y-axis side. The bobbin step portion 31b is formed on the back surface of the fixed main body portion 230b, at the corner where the end portion (side portion) of the fixed main body portion 230b on the negative X-axis side intersects with the end portion on the negative Y-axis side.

Bobbin step portion 31a is formed adjacent to bobbin protrusion 30a, and bobbin step portion 31b is formed adjacent to bobbin protrusion 30b. Furthermore, bobbin protrusion 30a is formed between flange engagement portion 24a and bobbin step portion 31a in the Y-axis direction, and bobbin protrusion 30b is formed between flange engagement portion 24b and bobbin step portion 31b in the Y-axis direction.

The flange engagement portion 24a, bobbin protrusion 30a, and bobbin step portion 31a all function to form an engagement state with the terminal block 70, and are concentrated at the end of the fixed main body portion 230a in the X-axis direction. The flange engagement portion 24b, bobbin protrusion 30b, and bobbin step portion 31b all function to form an engagement state with the terminal block 70, and are concentrated at the end of the fixed main body portion 230b in the X-axis direction.

The bobbin step portions 31a and 31b form a step on the back surface of the fixed main body portions 230a and 230b. The bobbin step portions 31a and 31b have a stepped shape (concave shape) recessed to a predetermined depth in the Z-axis direction from the back surface of the fixed main body portions 230a and 230b, and the shape of the bobbin step portions 31a and 31b when viewed from the Z-axis direction is approximately rectangular (see Figure 10).

The bobbin step portion 31a has a step lower surface 310a (a substantially rectangular surface having a predetermined length in the X-axis direction and a predetermined length in the Y-axis direction) that is approximately parallel to the back surface of the fixed main body portion 230a. The bobbin step portion 31b has a step lower surface 310b (a substantially rectangular surface having a predetermined length in the X-axis direction and a predetermined length in the Y-axis direction) that is approximately parallel to the back surface of the fixed main body portion 230b. The step lower surfaces 310a and 310b form the lower surfaces of the steps that form the bobbin step portions 31a and 31b. The upper surfaces of the steps that form the bobbin step portions 31a and 31b form the back surface of the fixed main body portion 230a. The bobbin step portion 31a engages with the terminal block step portion 74a (Figure 8) of the terminal block 70, and the bobbin step portion 31b engages with the terminal block step portion 74b (Figure 8) of the terminal block 70.

An extended flange 27a is formed above the flange main body 220a. The extended flange 27a is integrally connected to the upper part of the flange main body 220a and extends approximately parallel to the XZ plane relative to the flange main body 220a. In other words, the extended flange 27a has a shape that extends upward from the flange main body 220a, and constitutes part of the flange main body 220a. The extended flange 27a has a predetermined thickness in the Y-axis direction and has a surface that is approximately parallel to the XZ plane.

The flange engagement portion 24a described above is formed on the upper end of the flange main body 220a, at the end facing the negative X-axis direction, while the extended flange portion 27a is formed on the upper end of the flange main body 220a, at the end facing the positive X-axis direction. The extended flange portion 27a is positioned at a predetermined distance along the X-axis direction relative to the flange engagement portion 24a, and protrudes above the fixed main body portion 230a of the terminal block fixing portion 23a.

A partition 26a is formed between the flange engagement portion 24a and the extended flange portion 27a. The flange engagement portion 24a, the extended flange portion 27a, and the partition 26a are arranged along the X-axis direction. The partition 26a is integrally connected to the upper part of the flange main body 220a and extends approximately parallel to the XZ plane relative to the flange main body 220a. In other words, the partition 26a has a shape that extends upward from the flange main body 220a, and constitutes part of the flange main body 220a. The partition 26a has a predetermined thickness in the Y-axis direction and has a surface that is approximately parallel to the XZ plane.

An extension flange 27b and a partition 26b are formed above the flange main body 220b. The configurations of the extension flange 27b and the partition 26b are similar to those of the extension flange 27a and the partition 26a, so a detailed description will be omitted.

A notch 28a is formed between the flange engagement portion 24a and the partition portion 26a, and a notch 29a is formed between the extension flange portion 27a and the partition portion 26a. Either the lead portion 41a or 41b of the first wire 41c (Figure 3) can be inserted into the notch 28a. The same applies to the notch 29a.

A notch 28b is formed between the flange engagement portion 24b and the partition portion 26b, and a notch 29b is formed between the extension flange portion 27b and the partition portion 26b. Either the lead portion 42a or 42b of the second wire 42c (Figure 3) can be inserted into the notch 28b. The same applies to the notch 29b.

In this embodiment, as shown in FIG. 2, of the lead portions 41a and 41b, the lead portion 41a is inserted through the notch 29a, and the lead portion 41a is pulled out from the inside to the outside in the Y-axis direction of the flange portion 22a via the notch 29a, and is also pulled out from the outside in the Y-axis direction of the flange portion 22a toward the terminal block 70. Therefore, when pulling the lead portion 41a out toward the terminal block 70, unnecessary routing of the lead portion 41a can be prevented.

On the other hand, lead portion 41b does not pass through either notch 28a or 29a, but is pulled out from the inside of flange portion 22a in the Y-axis direction toward terminal block 70. As a result, lead portion 41a passes outside flange engagement portion 24a in the Y-axis direction, and lead portion 41b passes inside flange engagement portion 24a in the Y-axis direction, thereby providing good insulation between lead portions 41a and 41b via flange engagement portion 24a.

In addition, a partition 26a is formed between the notch 28a and the notch 29a, which allows the position of the lead 41a inserted through the notch 29a to be adjusted by the partition 26a and prevents the lead 41a from shifting position.

Of the lead portions 42a and 42b, the lead portion 42a is inserted through the notch 28b, and the lead portion 42a is pulled out from the inside to the outside in the Y-axis direction of the flange portion 22b via the notch 28b, and is also pulled out from the outside in the Y-axis direction of the flange portion 22b toward the terminal block 70. Therefore, unnecessary routing of the lead portion 42a can be prevented when pulling the lead portion 42a toward the terminal block 70.

On the other hand, lead portion 42b is pulled out from the inside of flange portion 22b in the Y-axis direction toward terminal block 70 without passing through either notch 28b or 29b. As a result, lead portion 42a passes outside flange engagement portion 24b in the Y-axis direction, and lead portion 42b passes inside flange engagement portion 24b in the Y-axis direction, thereby providing good insulation between lead portions 42a and 42b via flange engagement portion 24b.

A partition 26b is formed between notches 28b and 29b, allowing the position of the lead 42a inserted through notch 28b to be adjusted by partition 26b and preventing misalignment of the lead 42a.

As shown in Figures 6 and 7, in this embodiment, the winding core portion 21 has protrusions 33 and 34. The protrusions 33 and 34 have the function of adjusting the leakage characteristics between the first coil portion 41 (Figure 3) and the second coil portion 42 depending on their circumferential length (or length along the X-axis direction) or length along the Y-axis direction (thickness).

Protrusions 33 and 34 are integrally formed on the outer peripheral surface of winding core 21, extending outward from the outer peripheral surface of winding core 21 and extending circumferentially around winding core 21. Protrusions 33 and 34 are formed on the long side of the outer peripheral surface of winding core 21. That is, protrusion 33 is formed on the upper portion of the outer peripheral surface of winding core 21, and protrusion 34 is formed on the lower portion of the outer peripheral surface of winding core 21. Note that the upper and lower portions of the outer peripheral surface of winding core 21 are generally flat, and it is preferable that protrusions 33 and 34 be formed on the generally flat surface of winding core 21 as described above rather than on the curved portions (side portions) of winding core 21.

Protrusions 33 and 34 are formed approximately in the center of the axial direction (Y-axis direction) of winding core 21. Protrusions 33 and 34 are arranged on opposite sides of each other along the radial direction of winding core 21, and are formed at corresponding positions in the Z-axis direction.

Protrusions 33 and 34 have the same shape, and are generally rectangular parallelepipeds (flattened shapes) with their longitudinal direction in the direction perpendicular to the axial direction of winding core 21 (X-axis direction). The length of protrusions 33 and 34 along the X-axis direction is greater than their length (height) along the Z-axis direction, and the length of protrusions 33 and 34 along the Z-axis direction is greater than their thickness along the Y-axis direction. The end (upper end) of protrusion 33 in the Z-axis direction has a curved surface (rounded corners), but the shape of protrusion 33 is not limited to this. Although detailed illustrations are omitted, the same applies to the shape of protrusion 34.

The length of the protrusion 33 along the circumferential direction of the winding core 21 (or the length of the protrusion 33 along the X-axis direction) is shorter than the length along the circumferential direction of the winding core 21. As shown in FIG. 9 , the ratio L3/L4 of the length L3 of the protrusion 33 along the circumferential direction of the winding core 21 (or the length L3 of the protrusion 33 along the X-axis direction) to the length L4 (not shown) along the circumferential direction of the winding core 21 (total length) is preferably 0 < L3/L4 < 1/2, more preferably 0 < L3/L4 < 1/4, and particularly preferably 1/10 < L3/L4 < 1/5. By appropriately adjusting the value of L3/L4 within the above range, the leakage characteristics between the first coil portion 41 (FIG. 3) and the second coil portion 42 can be appropriately adjusted to the desired value. The same applies to the ratio between the length of the protrusion 34 along the circumferential direction of the winding core 21 (or the length of the protrusion 34 along the X-axis direction) and the length along the circumferential direction of the winding core 21.

The length of the protrusion 33 along the circumferential direction of the winding core 21 (or the length of the protrusion 33 along the X-axis direction) is shorter than the length of the winding core 21 along the X-axis direction. The ratio L3/L5 of the length L3 of the protrusion 33 along the circumferential direction of the winding core 21 (or the length L5 of the protrusion 33 along the X-axis direction) to the length L5 of the winding core 21 along the X-axis direction is preferably 0 < L3/L5 < 1, more preferably 0 < L3/L5 < 3/4, and particularly preferably 1/6 < L3/L5 < 2/3. By appropriately adjusting the value of L3/L5 within the above range, the leakage characteristics between the first coil portion 41 (Figure 3) and the second coil portion 42 can be appropriately adjusted to the desired value. The same applies to the ratio between the length of the protrusion 34 along the circumferential direction of the winding core 21 (or the length of the protrusion 34 along the X-axis direction) and the length of the winding core 21 along the X-axis direction.

The length L6 of the protrusion 33 along the Z-axis direction is determined, for example, according to the wire diameter of the first wire 41c (Figure 3) or the wire diameter of the second wire 42c. In this embodiment, the first wire 41c and the second wire 42c are each formed in two layers in the radial direction of the winding core 21. Therefore, so that the first coil portion 41 and the second coil portion 42 can be fixed by the protrusion 33, it is preferable that the length L6 be at least twice the wire diameter of the first wire 41c (Figure 3) or the wire diameter of the second wire 42c. In other words, the length L6 is preferably greater than the height of the first coil portion 41 or the second coil portion 42 from the outer circumferential surface of the winding core 21. The same applies to the length of the protrusion 34 along the Z-axis direction.

By determining the length L6 of the protrusion 33 along the Z-axis direction as described above, the protrusion 33 effectively prevents misalignment of the first wire 41c and the second wire 42c along the Y-axis direction at the position of the protrusion 33. Furthermore, by fixing the first wire 41c and the second wire 42c to the protrusion 33, loosening of the first coil portion 41 and the second coil portion 42 can be prevented. Furthermore, when the first wire 41c and the second wire 42c are wound around the outer circumferential surface of the winding core 21 so as to return between the axial end of the winding core 21 and the protrusions 33 and 34, the first wire 41c and the second wire 42c can be folded back while being fixed to the protrusions 33 and 34, thereby preventing variations in the position and number of turns of the first coil portion 41 and the second coil portion 42.

As shown in FIG. 7, the length L7 of the protrusion 33 along the axial direction of the winding core 21 is preferably smaller than the wire diameter of the first wire 41c or the second wire 42c. In this embodiment, the length L7 of the protrusion 33 is approximately equal to the thickness of the flange 22a or 22b along the Y-axis direction.

As shown in Figures 2 and 7, the first coil portion 41 is arranged on one side of the protrusions 33 and 34 in the Y-axis direction, and the second coil portion 42 is arranged on the other side of the protrusions 33 and 34 in the Y-axis direction. In other words, the protrusions 33 and 34 are arranged between the first coil portion 41 and the second coil portion 42 in the Y-axis direction.

The first coil portion 41 and the second coil portion 42 are in partial contact along the circumferential direction of the winding core portion 21, with the protrusions 33 and 34 sandwiched between them. In other words, when viewed along the circumferential direction of the winding core portion 21, the first coil portion 41 and the second coil portion 42 do not come into contact at the position where the protrusion 33 is formed, because the protrusion 33 is interposed between them. In other words, the protrusion 33 separates the first coil portion 41 and the second coil portion 42 in the Y-axis direction, and a non-contact region 44 is formed between the first coil portion 41 and the second coil portion 42.

Furthermore, at the position where the protrusion 34 is formed, the first coil portion 41 and the second coil portion 42 do not come into contact with each other because the protrusion 34 is interposed between them. In other words, the protrusion 34 separates the first coil portion 41 and the second coil portion 42 in the Y-axis direction, and a non-contact region 45 is formed between the first coil portion 41 and the second coil portion 42.

On the other hand, in positions where protrusions 33 and 34 are not formed, the first coil portion 41 and the second coil portion 42 come into contact with each other because protrusions 33 and 34 are not interposed between them. As a result, a contact region 43 is formed between the first coil portion 41 and the second coil portion 42.

The contact region 43 is formed so as to be sandwiched between the non-contact region 44 and the non-contact region 45, and is formed in a partial region along the circumferential direction of the winding core 21. The contact region 43 is formed from a side portion of the outer peripheral surface of the winding core 21, spanning the upper and lower portions of the outer peripheral surface of the winding core 21, and extends a predetermined length along the outer peripheral surface of the winding core 21 so as to bend in a roughly C-shape. The contact region 43 is formed discontinuously on one side and the other side of the winding core 21 in the X-axis direction. The non-contact regions 44 and 45 are formed in the upper and lower portions of the outer peripheral surface of the winding core 21, respectively, and extend a predetermined length along the X-axis direction. The contact region 43 and the non-contact region 44 or 45 are formed alternately along the circumferential direction of the winding core 21.

The length of the contact region 43 along the circumferential direction of the winding core 21 is longer than the length of the non-contact region 44 or 45 along the circumferential direction of the winding core 21, and most of the first coil portion 41 and the second coil portion 42 are in contact along the circumferential direction of the winding core 21. By forming only a portion of the non-contact regions 44 and 45 between the first coil portion 41 and the second coil portion 42 along the circumferential direction of the winding core 21, the leakage characteristics between the first coil portion 41 and the second coil portion 42 can be appropriately adjusted to a desired value.

As shown in FIG. 3, the terminal block 70 is formed separately from the bobbin 20 and is detachably attached to the bobbin 20. The terminal block 70 may be made of the same insulating material as the bobbin 20, but is preferably made of an insulating material with better formability or heat resistance. The terminal block 70 is disposed on the lateral side of the winding core 21 on the negative X-axis direction, spaced apart from the outer peripheral surface of the winding core 21 in a direction perpendicular to the axial direction of the winding core 21 (X-axis direction). Therefore, a gap G (FIG. 9) having a predetermined length in the X-axis direction is formed between the lateral portion of the outer peripheral surface of the winding core 21 and the terminal block 70, along the axial direction of the winding core 21.

As shown in FIG. 8, the terminal block 70 has a terminal block base portion 71, arm portions 72a and 72b, terminal block hook portions 73a and 73b, terminal block step portions 74a and 74b, terminal block recesses 75a and 75b, lead insertion grooves 76a and 76b, terminal fixing portions 77a_1 and 77a_2, terminal fixing portions 77b_1 and 77b_2, a cover mounting portion 78, and a bottom fixing portion 79.

The terminal block base 71 is a substantially rectangular parallelepiped columnar body with its longitudinal direction in the Y-axis direction. It is positioned to the side of the winding core 21 in the X-axis direction, substantially parallel to the axial direction of the winding core 21. The length of the terminal block base 71 along the Y-axis direction is substantially equal to the length of the bobbin 20 along the Y-axis direction. As shown in FIG. 5 , the terminal block base 71 (bottom surface of the terminal block base 71) is positioned above the center of the winding core 21 in the Z-axis direction, at a position spaced apart from the side portion of the outer circumferential surface of the winding core 21 in the X-axis direction, and also above the upper portion of the outer circumferential surface of the winding core 21. However, the height position at which the terminal block base 71 is installed is not limited thereto; the terminal block base 71 (bottom surface of the terminal block base 71) may be positioned at a height substantially equal to or lower than the upper portion of the outer circumferential surface of the winding core 21.

As shown in Figures 5 and 9, the terminal block base portion 71 is positioned at a position spaced a gap G to the side in the X-axis direction from the outer surface of the winding core portion 21, so the end of the terminal block base portion 71 on the positive X-axis side (the side where the bobbin 20 is located) and the outer surface of the winding core portion 21 do not overlap in the Z-axis direction.

However, the position of the terminal block base portion 71 may be shifted toward the positive X-axis direction, so that the end of the terminal block base portion 71 facing the positive X-axis direction and the outer peripheral surface of the winding core portion 21 overlap in the Z-axis direction (when viewed from the Z-axis direction). In other words, the position of the terminal block base portion 71 is not particularly limited as long as it is positioned a predetermined distance away from the outer peripheral surface of the winding core portion 21 in the radial direction of the winding core portion 21. For example, the terminal block base portion 71 may be positioned a predetermined distance to the side of the winding core portion 21 (negative X-axis direction) from any position on the outer peripheral surface of the winding core portion 21, and may also be positioned a predetermined distance above the winding core portion 21 (positive Z-axis direction) from that position on the outer peripheral surface of the winding core portion 21.

The position of the end (side) of the terminal block base portion 71 on the positive side of the X-axis is approximately the same as the position of the ends of the flange engagement portions 24a and 24b of the bobbin 20 on the negative side of the X-axis, and they are arranged closely together.

As shown in FIG. 8, arm portion 72a is formed on one side of terminal block base portion 71 in the Y-axis direction, and arm portion 72b is formed on the other side of terminal block base portion 71 in the Y-axis direction. Arm portions 72a and 72b protrude a predetermined length from the end (side) of terminal block base portion 71 in the X-axis direction toward the bobbin 20. As shown in FIG. 9, the length of arm portions 72a and 72b along the X-axis direction is longer than the length of the above-mentioned gap G in the X-axis direction, and is approximately equal to the length of flange engagement portions 24a and 24b of the bobbin 20 along the X-axis direction.

As shown in Figure 8, a hook-shaped terminal block hook portion 73a is formed at the tip of arm portion 72a, and a hook-shaped terminal block hook portion 73b is formed at the tip of arm portion 72b. Terminal block hook portions 73a and 73b protrude a predetermined length from the tips of arm portions 72a and 72b along the Y-axis direction, in directions approaching each other (toward the inside of terminal block 70). The protruding direction of terminal block hook portions 73a and 73b is approximately perpendicular to the longitudinal direction of arm portions 72a and 72b.

As shown in FIG. 10, when the terminal block 70 is fixed to the terminal block fixing portions 23a and 23b of the bobbin 20, the arm portion 72a is positioned along the outer surface of the flange engagement portion 24a of the bobbin 20 in the Y-axis direction, and the terminal block hook portion 73a engages with the side portion of the flange engagement portion 24a facing the positive X-axis direction. Furthermore, the arm portion 72b is positioned along the outer surface of the flange engagement portion 24b of the bobbin 20 in the Y-axis direction, and the terminal block hook portion 73b engages with the side portion of the flange engagement portion 24b facing the positive X-axis direction. This allows the terminal block 70 to be attached to the terminal block fixing portions 23a and 23b via the arm portions 72a and 72b.

When the terminal block hook portion 73a is engaged with the flange engagement portion 24a, the lead portion 41a of the first wire 41c shown in FIG. 2 is drawn out along the periphery of the arm portion 72a toward the terminal block 70. When the terminal block hook portion 73b is engaged with the flange engagement portion 24b, the lead portion 42a of the second wire 42c shown in FIG. 2 is drawn out along the periphery of the arm portion 72b toward the terminal block 70. Because the lead portions 41a and 41b are drawn out along the outer surfaces (outer surfaces in the Y-axis direction) of the arm portions 72a and 72b, respectively, the arm portions 72a and 72b serve to guide the lead portions 41a and 41b toward the terminal block 70.

As shown in FIG. 8, terminal block step portion 74a is formed at one end of terminal block base portion 71 in the Y-axis direction, and terminal block step portion 74b is formed at the other end of terminal block base portion 71 in the Y-axis direction. Terminal block step portions 74a and 74b are positioned further outward in the Y-axis direction than arm portions 72a and 72b.

The terminal block step portion 74a has a step lower surface 740a (a roughly rectangular surface having a predetermined length in the X-axis direction and a Y-axis direction) that is approximately parallel to the upper or lower surface of the terminal block base portion 71. The terminal block step portion 74b has a step lower surface 740b (a roughly rectangular surface having a predetermined length in the X-axis direction and a Y-axis direction) that is approximately parallel to the upper or lower surface of the terminal block base portion 71. The step lower surfaces 740a and 740b form the lower surfaces of the steps that form the terminal block step portions 74a and 74b.

As shown in Figures 9 and 10, the terminal block step portions 74a and 74b engage with the bobbin step portions 31a and 31b of the bobbin 20. More specifically, when the step lower surfaces 740a and 740b of the terminal block step portions 74a and 74b abut against the step lower surfaces 310a and 310b of the bobbin step portions 31a and 31b, the terminal block step portions 74a and 74b engage with the bobbin step portions 31a and 31b.

As shown in FIG. 8, terminal block recess 75a is formed at one end of terminal block base portion 71 in the Y-axis direction, and terminal block recess 75b is formed at the other end of terminal block base portion 71 in the Y-axis direction. Terminal block recess 75a is located between arm portion 72a and terminal block step portion 74a in the Y-axis direction, and terminal block recess 75b is located between arm portion 72b and terminal block step portion 74b in the Y-axis direction. Terminal block recesses 75a and 75b are recesses with a predetermined depth, and the positive X-axis side of terminal block recesses 75a and 75b is open. The depth of terminal block recesses 75a and 75b is approximately equal to the thickness along the Z-axis direction of bobbin protrusions 30a and 30b (FIG. 6) of bobbin 20.

The terminal block recesses 75a and 75b are recessed a predetermined length from the end (side) of the terminal block base 71 on the positive X-axis side toward the negative X-axis side. The bottom surfaces of the terminal block recesses 75a and 75b are roughly rectangular, corresponding to the shapes of the upper and lower surfaces of the bobbin protrusions 30a and 30b of the bobbin 20.

As shown in Figures 9 and 10, the terminal block recesses 75a and 75b engage with the bobbin protrusions 30a and 30b of the bobbin 20. More specifically, the bobbin protrusions 30a and 30b are housed inside the terminal block recesses 75a and 75b, respectively, thereby engaging the terminal block recesses 75a and 75b with the bobbin protrusions 30a and 30b.

In this way, in this embodiment, by engaging the terminal block hook portions 73a and 73b with the flange engagement portions 24a and 24b as the first engagement portions, it is possible to prevent misalignment of the terminal block 70 along the X-axis direction relative to the terminal block fixing portions 23a and 23b.

Furthermore, by engaging the terminal block step portions 74a and 74b with the bobbin step portions 31a and 31b as second engagement portions, it is possible to prevent misalignment of the terminal block 70 along the Z-axis direction relative to the terminal block fixing portions 23a and 23b.

Furthermore, by engaging the terminal block recesses 75a and 75b with the bobbin protrusions 30a and 30b as a third engagement portion, it is possible to prevent misalignment of the terminal block 70 along the Y-axis direction relative to the terminal block fixing portions 23a and 23b. This allows the terminal block 70 to be attached to the terminal block fixing portions 23a and 23b with sufficient fixing strength.

Furthermore, by engaging the above-mentioned engaging portions, the terminal block 70 can be connected to one end and the other end of the winding core portion 21 in the axial direction, and can be positioned approximately parallel to the axial direction of the winding core portion 21. The terminal block 70 is fixed to the terminal block fixing portions 23a and 23b by three-point support at the above-mentioned engaging portions, and does not need to be fixed using adhesive or the like. Note that any of the above-mentioned engaging portions may be omitted. Furthermore, if necessary, fixing (reinforcement) may be performed using adhesive or the like.

As shown in Figure 8, the cover mounting portion 78 is formed in approximately the center of the terminal block base portion 71 in the Y-axis direction. The cover mounting portion 78 has approximately flat upper and lower surfaces, and the grip portion 84 of the cover portion 80 is fixed to the cover mounting portion 78.

Terminal fixing portions 77a_1 and 77a_2 are formed on one side of cover mounting portion 78 in the Y-axis direction. Terminal fixing portion 77a_1 is positioned further outward in the Y-axis direction than terminal fixing portion 77a_2. Terminal fixing portions 77a_1 and 77a_2 are formed thicker than the surrounding areas, allowing terminals 61_1 and 61_2 to be fixed to terminal fixing portions 77a_1 and 77a_2, respectively.

Terminal insertion grooves 770a_1 and 770a_2 are formed in terminal fixing portions 77a_1 and 77a_2, respectively. Terminal insertion grooves 770a_1 and 770a_2 are bent in a generally L-shape to correspond to the shapes of terminals 61_1 and 61_2. Terminals 61_1 and 61_2 are fixed to terminal fixing portions 77a_1 and 77a_2 by integral molding (insert molding).

Terminal fixing portions 77b_1 and 77b_2 are formed on the other side of cover mounting portion 78 in the Y-axis direction. Terminal fixing portion 77b_1 is positioned further outward in the Y-axis direction than terminal fixing portion 77b_2. Terminal fixing portions 77b_1 and 77b_2 are formed thicker than their surrounding areas, allowing terminals 62_1 and 62_2 to be fixed to terminal fixing portions 77b_1 and 77b_2, respectively.

Terminal insertion grooves 770b_1 and 770b_2 are formed in terminal fixing portions 77b_1 and 77b_2, respectively. Terminal insertion grooves 770b_1 and 770b_2 are grooves that are bent in a roughly L-shape to correspond to the shapes of terminals 62_1 and 62_2. Terminals 62_1 and 62_2 are fixed to terminal fixing portions 77b_1 and 77b_2 by integral molding (insert molding).

Lead insertion groove 76a is formed between terminal fixing portion 77a_1 and terminal fixing portion 77a_2, and lead insertion groove 76b is formed between terminal fixing portion 77b_1 and terminal fixing portion 77b_2. Lead insertion grooves 76a and 76b are recesses recessed from the end of terminal block base portion 71 on the positive X-axis side, and extend from the upper end to the lower end of terminal block base portion 71. The lead portion 41b of the first wire 41c is inserted into lead insertion groove 76a, and the lead portion 42b of the second wire 41c is inserted into lead insertion groove 76b (see Figure 2).

The bottom surface fixing portion 79 is formed in a stepped shape on the bottom surface of the terminal block base portion 71 at the end on the negative X-axis direction side of the terminal block base portion 71 (opposite the side on which the bobbin 20 is arranged). The bottom surface fixing portion 79 has a substantially flat surface and has a predetermined length along the X-axis direction and a predetermined length along the Y-axis direction. The bottom surface fixing portion 79 is formed along the Y-axis direction from one end of the terminal block base portion 71 to the other end in the Y-axis direction. The X-axis end of the cover bottom portion 81 of the cover portion 80 is fixed to the bottom surface fixing portion 79.

Terminals 61_1, 61_2, 62_1, and 62_2 are attached to terminal block 70 at a predetermined interval along the Y-axis direction. Terminals 61_1 and 61_2 have the same shape and are fixed to terminal fixing portions 77a_1 and 77a_2, respectively. Lead portion 41a of first wire 41c is connected to terminal 61_1, and lead portion 41b of first wire 41c is connected to terminal 61_2.

Furthermore, terminals 62_1 and 62_2 have the same shape and are fixed to terminal fixing portions 77b_1 and 77b_2, respectively. The lead portion 42a of the second wire 42c is connected to terminal 62_1, and the lead portion 42b of the second wire 42c is connected to terminal 62_2.

The terminal 61_1 has an external connection portion 610_1, a connecting portion 611_1, a connection wire bottom portion 612_1, and a connection wire fold portion 613_1. The external connection portion 610_1 is the portion that is connected to the mounting board, and protrudes from the upper portion of the terminal fixing portion 77a_1 (terminal insertion groove 770a_1) and extends upward. The external connection portion 610_1 protrudes upward beyond the upper edge of the case 90 (Figure 1).

The connecting portion 611_1 connects the external connection portion 610_1 and the connecting wire bottom portion 612_1, and extends toward the negative X-axis direction while bending outward in the Y-axis direction.

The connecting wire bottom portion 612_1 and the connecting wire fold portion 613_1 are portions that connect the lead portion 41a, and are capable of sandwiching (crimping) the lead portion 41a between the connecting wire bottom portion 612_1 and the connecting wire fold portion 613_1. The connecting wire fold portion 613_1 is integrally connected to the outer end of the connecting wire bottom portion 612_1 in the Y-axis direction, and is positioned opposite the connecting wire bottom portion 612_1 in the Z-axis direction. The connecting wire fold portion 613_1 has a curved surface, but may also be formed in a substantially flat shape.

Terminal 61_2 has an external connection portion 610_2, a connecting portion 611_2, a wire connection bottom portion 612_2, and a wire connection fold portion 613_2. The shapes and functions of the components constituting terminal 61_2 are similar to those of terminal 61_1, and therefore detailed descriptions thereof will be omitted.

Terminal 62_1 has an external connection portion 620_1, a connecting portion 621_1, a connection wire bottom portion 622_1, and a connection wire fold portion 623_1. Terminal 62_1 differs from terminal 61_1 in that it is formed symmetrically with respect to the X-axis. In all other respects, terminal 62_1 is the same as terminal 61_1, so a detailed description of terminal 62_1 will be omitted.

Terminal 62_2 has an external connection portion 620_2, a connecting portion 621_2, a connection wire bottom portion 622_2, and a connection wire fold portion 623_2. Terminal 62_2 differs from terminal 61_2 in that it is formed symmetrically with respect to the X-axis. In all other respects, terminal 62_2 is the same as terminal 61_2, so a detailed description of terminal 62_2 will be omitted.

The cover portion 80 has a cover bottom portion 81, an insulating portion 82, cover side portions 83a and 83b, and a grip portion 84. The cover portion 80 is formed separately from the terminal block 70 and is removably attached to the terminal block 70 so as to be positioned around the terminal block 70.

The cover bottom 81 has a plate surface that is approximately parallel to the XY plane and is positioned below the terminals 61_1 and 61_2 and terminals 62_1 and 62_2 that are attached to the terminal block 70. The tip of the cover bottom 81 in the X-axis direction is fixed in a state where it engages with the bottom fixing portion 79 of the terminal block 70. By fixing the cover bottom 81 to the bottom fixing portion 79, it is possible to prevent the cover 80 from shifting in the Z-axis direction relative to the terminal block 70.

The insulating portion 82 is formed in approximately the center of the cover portion 80 in the Y-axis direction. An insulating recess 820 is formed in the insulating portion 82. The insulating recess 820 is recessed downward from the top surface of the insulating portion 820 and recessed from the side surface of the insulating recess 820 on the negative X-axis direction side toward the positive X-axis direction. Terminal 61_2 is arranged on one side of the insulating portion 82 in the Y-axis direction, and terminal 62_2 is arranged on the other side of the insulating portion 82 in the Y-axis direction.

By forming an insulating portion 82 with an insulating recess 820 on the cover portion 80, it is possible to extend the insulation distance between the terminal 61_2 to which the lead portion 41b of the first wire 41c is connected and the terminal 62_2 to which the lead portion 42b of the second wire 42c is connected, thereby achieving good insulation between these wires (primary coil and secondary coil).

The cover side portions 83a and 83b extend upward and rise from the end of the cover bottom portion 81 on the negative side of the X-axis, generally perpendicular to the cover bottom portion 81. The cover side portion 83a is formed on one side of the insulating portion 82 in the Y-axis direction, and the cover side portion 83b is formed on the other side of the insulating portion 82 in the Y-axis direction.

By forming the cover bottom 81 and cover side portions 83a and 83b on the cover portion 80, terminals 61_1 and 61_2 and terminals 62_1 and 62_2 attached to the terminal block 70 can be protected from external forces, etc. Furthermore, the cover bottom 81 and cover side portion 83a provide excellent insulation between terminals 61_1 and 61_2 and core 50a (Figure 3), and the cover bottom 81 and cover side portion 83b provide excellent insulation between terminals 62_1 and 62_2 and core 50b (Figure 3).

The gripping portion 84 is formed approximately in the center of the cover bottom portion 81 in the Y-axis direction and protrudes from the position of the insulating portion 82 toward the terminal block 70. The gripping portion 84 is used to grip the cover mounting portion 78 of the terminal block 70.

The gripping portion 84 has an upper arm 841 and a lower arm 842. The upper arm 841 is formed at the upper end of the insulating portion 82 and extends toward the terminal block 70. The lower arm 842 is formed at the lower end of the insulating portion 82 (at the position of the cover bottom 81) and extends toward the terminal block 70 so as to be approximately parallel to the upper arm 841. The tips of the upper arm 841 and the lower arm 842 are hook-shaped and bent toward each other. The upper arm 841 and the lower arm 842 grip the upper and lower surfaces of the cover mounting portion 78, respectively, allowing the gripping portion 84 to be attached to the cover mounting portion 78.

By gripping the cover mounting portion 78 of the terminal block 70 with the upper arm 841 and lower arm 842, it is possible to attach the cover portion 80 to the cover mounting portion 78 with sufficient fixing strength without using adhesives, etc., thereby reducing costs and speeding up manufacturing.

Next, a method for manufacturing the coil device 10 will be described with reference to Figure 3 and other figures. First, the components shown in Figure 3 are prepared. Terminals 61_1 and 61_2 and terminals 62_1 and 62_2 are attached to the terminal block 70 in advance by insert molding or the like. In addition, the cover portion 80 is attached to the terminal block 70. These are attached by gripping the cover mounting portion 78 of the terminal block 70 with the gripping portion 84 of the cover portion 80; no adhesive or the like is required.

Next, the first wire 41c and the second wire 42c are wound around the outer peripheral surface of the winding core 21 of the bobbin 20, forming the first coil portion 41 on one side of the protrusions 33 and 34 in the Y-axis direction, and the second coil portion 42 on the other side. The lead portions 41a and 41b of the first wire 41c are pulled out from one axial end of the winding core 21. The lead portions 42a and 42b of the second wire 42c are pulled out from the other axial end of the winding core 21.

Next, one end of the terminal block 70 in the Y-axis direction is fixed to the terminal block fixing portion 23a of the bobbin 20, and the other end of the terminal block 70 in the Y-axis direction is fixed to the terminal block fixing portion 23b of the bobbin 20, and the terminal block 70 is positioned a predetermined distance outward (to the side) in the X-axis direction from the outer circumferential surface of the winding core portion 21.

Next, lead portion 41a is connected to terminal 61_1 by crimping or the like, lead portion 41b is connected to terminal 61_2 by crimping or the like, lead portion 42a is connected to terminal 62_1 by crimping or the like, and lead portion 42b is connected to terminal 62_2 by crimping or the like (see Figure 2). Next, center leg portion 53a of core 50a and center leg portion 53b of core 50b are inserted into through-hole 211 of bobbin 20, and cores 50a and 50b are attached to bobbin 20.

Next, the bobbin 20 and other components are placed inside the case 90, and the potting resin 100 is filled into the case 90, thereby obtaining the coil device 10 shown in Figure 1.

As described above, the coil device 10 according to this embodiment has a terminal block 70 formed separately from the bobbin 20, as shown in FIG. 3. Therefore, when manufacturing the coil device 10, the first wire 41c and the second wire 42c can be wound around the outer circumferential surface of the winding core 21 with the terminal block 70 removed from the bobbin 20. This prevents the terminal block 70 from interfering with the automatic winding, particularly when winding the first wire 41c and the second wire 42c using an automatic winding machine. Furthermore, by forming only the terminal block 70 from a highly heat-resistant resin, separate from the bobbin 20, a heat-resistant coil device 10 can be realized at low cost.

In addition, the terminal block 70 is positioned at a distance in the X-axis direction from the outer peripheral surface of the winding core 21. This allows the terminal block 70 to be positioned to the side of the winding core 21 in the X-axis direction, making it possible to reduce the size of the coil device 10 in both the X-axis and Z-axis directions, thereby achieving a more compact coil device 10.

Furthermore, the terminal block 70 is arranged approximately parallel to the axial direction of the winding core 21. This prevents the terminal block 70 from being arranged in an unnecessarily protruding state to the side of the winding core 21 in the X-axis direction, thereby reducing the size of the coil device 10 in the X-axis direction.

In addition, in this embodiment, as shown in FIG. 8, the arm portions 72a and 72b are engaged with the flange engagement portions 24a and 24b (FIG. 6) via the terminal block hook portions 73a and 73b. This makes it possible to attach the terminal block 70 to the bobbin 20 with sufficient fixing strength without using adhesives or the like, thereby reducing costs and speeding up manufacturing. Furthermore, the terminal block 70 can be positioned at a distance in the X-axis direction from the outer peripheral surface of the winding core portion 21 that corresponds to the length of the arm portions 72a and 72b. The position of the terminal block 70 can be adjusted by appropriately changing the length of the arm portions 72a and 72b.

In addition, in this embodiment, the lead portion 41a of the first wire 41c and the lead portion 42a of the second wire 42c are pulled out toward the terminal block 70 along the periphery of the arm portions 72a and 72b, respectively (see Figures 2, 9, and 10). This makes it possible to pull the lead portions 41a and 42a from the winding core portion 21 to the terminal block 70 over a short distance, preventing unnecessary routing of the lead portions 41a and 42a (increasing the wire length of the lead portions 41a and 42a), improving the quality of the coil device 10, and contributing to reducing electrical resistance and suppressing resonance of the first wire 41c and the second wire 42c.

Furthermore, as shown in Figure 6, bobbin hooks 25a and 25b are formed on the flange engagement portions 24a and 24b, preventing the lead portions 41a and 42a drawn out along the periphery of the arm portions 72a and 72b from shifting position toward the upper ends of the flange engagement portions 24a and 24b.

In addition, in this embodiment, as shown in FIG. 1, heat generated in the bobbin 20 and the like can be dissipated to the outside via the case 90 and potting resin 100, allowing for efficient cooling of the coil device 10. Furthermore, as shown in FIG. 6, the bobbin 20 is formed with through-holes 35a and 35b and through-holes 36a and 36b, which allow the potting resin 100 to circulate inside and outside the bobbin 20, allowing the potting resin 100 to reach every corner of the case 90.

Second Embodiment A coil device 110 according to a second embodiment of the present invention is similar in configuration to the first embodiment described above, with the only difference being the following: In the drawings, members common to the first embodiment are designated by the same reference numerals, and descriptions of overlapping parts will be omitted.

As shown in FIG. 11 , coil device 110 has terminal blocks 70_1 and 70_2 and cover portions 80_1 and 80_2. That is, coil device 110 in this embodiment is similar to coil device 10 in the first embodiment in that it has terminal block 70_1 and cover portion 80_1 located away from the outer peripheral surface of winding core portion 21 in the negative X-axis direction, but differs from coil device 10 in the first embodiment in that it also has terminal block 70_2 and cover portion 80_2 located away from the outer peripheral surface of winding core portion 21 in the positive X-axis direction.

As shown in FIG. 12, in order to enable attachment of terminal block 70_2, terminal block fixing portions 23a and 23b of winding core portion 120 are formed with flange engagement portions 24a and 24b, bobbin protrusions 30a and 30b, and bobbin step portions 31a and 31b at the end on the positive X-axis side in addition to the end on the negative X-axis side. Therefore, the shape of one side of bobbin 120 from the center in the X-axis direction is the same as the shape of the other side of bobbin 120 from the center in the X-axis direction (they are symmetrical).

This embodiment also achieves the same effects as the first embodiment. Additionally, in this embodiment, because terminal blocks 70_1 and 70_2 are formed on both sides of the winding core 21 in the X-axis direction, the lead portions 41a and/or 41b of the first wire 41c can be pulled out and secured to the side where terminal block 70_2 is located, instead of the side where terminal block 70_1 is located. Furthermore, the lead portions 42a and/or 42b of the second wire 42c can be pulled out and secured to the side where terminal block 70_2 is located, instead of the side where terminal block 70_1 is located. Furthermore, for example, when four wires are wound around the outer peripheral surface of the winding core 21, the lead portions of each wire can be connected to each of the eight terminals shown in FIG. 11.

Note that the present invention is not limited to the above-described embodiments and can be modified in various ways within the scope of the present invention.

In the above embodiments, examples of application of the present invention to transformers have been described, but the present invention can also be applied to other coil devices.

In the above embodiments, cores 50a and 50b are each configured as an E-shaped core, but one of cores 50a and 50b may be configured as an E-shaped core and the other as an I-shaped core. Alternatively, cores 50a and 50b may each be configured as a U-shaped core. Alternatively, one of cores 50a and 50b may be configured as a U-shaped core and the other as an I-shaped core. Alternatively, core 50a may be configured as a combination of two U-shaped cores, and core 50b may be configured as a combination of two U-shaped cores.

In the above embodiments, multiple (four) through-holes (through-holes 35a, 35b, 36a, 36b) were formed on the outer peripheral surface of the winding core 21, but the number of through-holes may be one. For example, only one through-hole may be formed in either the upper or lower portion of the outer peripheral surface of the winding core 21. The number of through-holes may also be two to three, or five or more.

In the first embodiment described above, lead portion 41a may be inserted through notch 28a shown in Figure 2. Furthermore, of lead portions 41a and 41b, lead portion 41b may be inserted through notch 28a or notch 29a.

Similarly, lead portion 42a may be inserted through notch 29b. Furthermore, of lead portions 42a and 42b, lead portion 42b may be inserted through notch 28b or notch 29b.

In the above embodiments, the protrusions 33 and 34 were formed approximately in the center of the winding core 21 in the Y-axis direction, but they may also be formed in a position shifted to one side or the other in the Y-axis direction from that position.

In each of the above embodiments, two protrusions (protrusions 33 and 34) were formed on the winding core 21, but the number of protrusions may be one, or three or more.

In each of the above embodiments, two coil sections (first coil section 41 and second coil section 42) were formed on the winding core section 21, but three or more coil sections may also be formed.

10, 110... Coil device, 20, 120... Bobbin, 21... Winding core portion, 211... Through hole, 22a, 22b... Flange portion, 220a, 220b... Flange portion main body, 23a, 23b... Terminal block fixing portion, 230a, 230b... Fixing main body portion, 24a, 24b... Flange engagement portion, 25a, 25b... Bobbin hook portion, 26a, 26 b...partition portion, 27a, 27b...extension flange portion, 28a, 28b, 29a, 29b...notch portion, 30a, 30b...bobbin protrusion portion, 31a, 31b...bobbin step portion, 310a, 310b...step lower surface, 32a, 32b...placing portion, 33, 34...protrusion portion, 35a, 35b, 36a, 36b...through hole portion, 37a , 37b...concave bottom portion, 41...first coil portion, 42...second coil portion, 41a, 41b...first lead portion, 41c...first wire, 42a, 42b...second lead portion, 42c...second wire, 43...contact region, 44, 45...non-contact region, 50a, 50b...core, 51a, 51b...base portion, 510a, 510b...outer surface, 511a, 511b...inner surface, 512a, 512b...upper surface, 513a, 513b...lower surface, 52a, 52b...outer leg portion, 520a, 520b...inner surface of outer leg, 53a, 53b...middle leg portion, 54a, 54b...upper recess, 540a, 540b...upper bottom surface, 541a, 541b...upper taper Surface, 55a, 55b... lower recess, 550a, 550b... lower bottom surface 550a, 551b... lower tapered surface, 56a, 56b... thick portion, 61_1, 61_2, 62_1, 62_2... terminal, 610_1, 610_2, 620_1, 620_2... external connection portion, 611_1, 611_2, 621_1, 621_2... Connection part, 612_1, 612_2, 622_1, 622_2... Connection line bottom, 613_1, 613_2, 623_1, 623_2... Connection line Folding part, 70, 70_1, 70_2...Terminal block, 71...Terminal block base part, 72a, 72b...Arm part, 73a, 73b...Terminal block hook part, 74a, 74 b...terminal block step portion, 740a, 740b...step underside, 75a, 75b...terminal block recess, 76a, 76b...lead insertion groove, 77a_1, 77a_2, 77b_1, 77b_2...terminal fixing portion, 770a_1, 770a_2, 770b_1, 770b_2...terminal insertion groove, 78...cover mounting portion, 79...bottom fixing portion, 80, 80_1, 80_2...cover portion, 81...cover bottom portion, 82...insulating portion, 820...insulating recess, 83a, 83b...cover side portion, 84...gripping portion, 841...upper arm, 842...lower arm, 90...case, 91...case bottom, 92...case side, 93...joint portion, 100...resin.

Claims (10)

a bobbin having a winding core portion around which a wire is wound and a flange portion formed at an axial end of the winding core portion;
a terminal block formed separately from the bobbin and attached to the bobbin,
the terminal block is disposed at a position spaced apart from the outer peripheral surface of the winding core in a direction perpendicular to the axial direction of the winding core ,
The flange of the bobbin is formed with a flat terminal block fixing body portion that protrudes substantially perpendicularly from an outer end surface of the flange,
the terminal block fixing body has a bobbin protrusion,
The terminal block has a terminal block base portion, and a terminal block extension portion at a longitudinal end of the terminal block base portion, the terminal block extension portion having a terminal block recess formed therein;
an arm portion protruding toward the terminal block fixing body portion is formed on the terminal block base portion on the inner side along the longitudinal direction of the terminal block recess,
The bobbin protrusion and the terminal block recess engage with each other,
the arm portion is attached to the bobbin above the terminal block fixing body portion,
The lead-out portion of the wire is led out along the arm portion toward the terminal block.
Coil device. The coil device described in claim 1, wherein the terminal block is arranged approximately parallel to the axial direction of the winding core portion. a first hook portion having a hook shape is formed at the tip of the arm portion ,
3. The coil device according to claim 1, wherein the flange portion is formed with a flange engaging portion that extends in a direction substantially perpendicular to the terminal block fixing main body portion and that engages with the first hook portion. A second hook portion having a hook shape is formed at the tip end of the flange engagement portion,
The coil device according to claim 3 , wherein the lead-out portion of the wire is led out along the arm portion toward the terminal block with the first hook portion engaged with the flange engaging portion. the terminal block fixing body has a first step portion,
the terminal block base portion has a second step portion on the outer side along the longitudinal direction of the terminal block recess ,
A coil device as described in any one of claims 1 to 4, wherein the first step portion and the second step portion engage with each other when the first step lower surface of the first step portion and the second step lower surface of the second step portion are in contact with each other. The flange portion is formed along the circumferential direction of the winding core portion,
The coil device according to any one of claims 1 to 5 , wherein the flange portion has a notch formed therein through which the lead-out portion of the wire is inserted. One of the lead-out portions of the wire passes through the notch and is led out from the outside of the flange toward the terminal block,
The coil device according to claim 6 , wherein the other lead-out portion of the wire is led out from inside the flange toward the terminal block without passing through the notch. The terminal block further includes a cover portion disposed around the terminal block,
The wire comprises a plurality of wires,
a plurality of terminals to which the lead-out portions of the plurality of wires are respectively connected are attached to the terminal block along the axial direction of the winding core portion;
The coil device according to any one of claims 1 to 7 , wherein the cover portion has a gripping portion that grips the terminal block, a bottom portion that is positioned below the plurality of terminals, and a side portion that rises from a side end of the bottom portion. The coil device according to any one of claims 1 to 8 , wherein the axial direction of the winding core portion is approximately parallel to the mounting surface. The device further includes a case in which the bobbin is housed,
The case can be filled with a potting resin,
The coil device according to any one of claims 1 to 9 , wherein at least one through hole is formed in the outer peripheral surface of the winding core.