JP2014132622A - Coil component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coil component capable of connecting a lead part and a terminal while surely securing an insulation distance.SOLUTION: The coil component includes: a bobbin (40) including a first hollow cylindrical part (44) having a primary coil (20) wound around its outer periphery, and a bobbin substrate (42) in which a primary terminal to be connected to the primary coil and a secondary terminal (72) to be connected to a secondary coil are installed and which is connected to a lower end of the first hollow cylindrical part; and a case (50) including a second hollow cylindrical part (54) which can be attached to the outer periphery of the primary coil and has the secondary coil wound around its outer periphery, a lower flange part (58) connected to a lower end of the second hollow cylindrical part so as to be attached to an upper surface of the bobbin substrate, and an upper flange part (52) connected to an upper end of the second hollow cylindrical part. At least one lead part (32a) of the secondary coil is connected to the secondary terminal after being pulled up from the second hollow cylindrical part to the upper flange part.

Description

  The present invention relates to a coil component suitably used as, for example, a resonant transformer.

  Coil components are used for various applications in various electrical products. For example, in driving a backlight of a liquid crystal display, an inverter resonance transformer is used to obtain a high voltage.

  A resonant transformer is required to realize external requirements such as a reduction in height in addition to electrical characteristics such as generation of appropriate leakage inductance. In the prior art, in order to meet such demands, a split structure in which the axial direction of the core is a horizontal type parallel to the installation surface, and the primary coil and the secondary coil are arranged separately along the axial direction of the core. Coil parts have been proposed. Further, the coil component having the divided structure has an advantage that it is relatively easy to insulate.

  However, the conventional technology has a problem that a large amount of leakage magnetic flux is generated in the downward direction where the installation surface on which the coil component is installed exists and in the opposite direction. For example, in a resonance transformer used for a backlight of a liquid crystal television, a structural material containing iron may be arranged in the vertical direction of a coil component. If it does so, the magnetic flux leakage from a coil component will generate the eddy current in a structural material etc., and the problem that the heat | fever and noise accompanying generation | occurrence | production of an eddy current will arise. In addition, in order to prevent magnetic flux leakage in the vertical direction, it is possible to take measures such as attaching an aluminum plate in the vertical direction of the coil component. However, such measures deteriorate the heat dissipation of the coil. There are problems such as.

  In order to solve such a problem, the secondary coil is arranged on the outer periphery of the primary coil by combining the bobbin substrate on which the primary coil is wound and the case on which the secondary coil is wound. The present applicant has proposed a coil component with a low profile.

  In such a coil component, it is necessary to pull out and connect the lead portion of the secondary coil wound around the case to the secondary terminal formed on the end of the bobbin substrate. When advanced, it becomes difficult to avoid contact between the lead portions in the vicinity of the terminals, and there is a problem that securing of the insulation distance prevents miniaturization of the coil component.

JP 2008-112753 A

  The present invention has been made in view of such a situation, and an object thereof is a coil component that can be reduced in height and size, and can connect a lead portion and a terminal while ensuring an insulation distance. Is to provide.

In order to achieve the above object, the coil component according to the present invention comprises:
A first hollow cylinder part around which the primary coil is wound, a primary terminal that connects the primary coil, and a secondary terminal that connects the secondary coil are installed and connected to the lower end of the first hollow cylinder part A bobbin substrate having a bobbin substrate,
A second hollow cylinder part that can be attached to the outer periphery of the primary coil and the secondary coil is wound around the outer periphery, and a lower end of the second hollow cylinder part that is attached to the upper surface of the bobbin substrate. A case having a lower collar part and an upper collar part connected to the upper end of the second hollow cylinder part;
A coil component comprising:
At least one lead part in the secondary coil is connected to the secondary terminal after being pulled up from the second hollow cylinder part to the upper collar part.

  In the coil component according to the present invention, since the secondary coil is arranged on the outer peripheral side of the primary coil, the shaft of the first hollow cylinder part around which the primary coil is wound and the second hollow cylinder part around which the secondary coil is wound The direction length can be shortened. Since these axial lengths are in the height direction of the coil component, the height of the coil component can be reduced. Furthermore, since the case that defines a part of the outer shape also serves as the bobbin of the secondary coil, the number of parts can be reduced while having a double structure.

  Further, since the primary terminal and the secondary terminal are formed on the bobbin substrate, it is not necessary to provide the terminal on the case. For this reason, it becomes possible to freely design the shape of the case, the degree of freedom in design is increased, the height is easily reduced, and a relatively inexpensive resin is selected as the case compared to the bobbin. It is possible to reduce the manufacturing cost. Note that the bobbin on which the terminal is formed is required to have heat resistance for soldering processing to the terminal.

  Further, in the present invention, at least one lead portion of the secondary coil is not pulled down from the second hollow cylinder portion to the secondary terminal and connected to the secondary terminal after being pulled up to the upper collar portion. It is connected. Thereby, it is possible to avoid that the lead parts connected to the secondary terminal come into contact with each other at a position close to the secondary terminal, such as the surface of the lower collar part. In particular, when the secondary terminal and the end portion of the lead portion are connected through a heating process such as soldering, the insulating coating of the lead portion may be thermally damaged in the vicinity of the secondary terminal. Therefore, it is preferable from the viewpoint of ensuring insulation that the lead wires are not in contact with each other in the vicinity of the secondary terminal. Further, by arranging the lead portions in this way, it is possible to perform wiring in a narrow range while ensuring insulation, and thus the coil component according to the present invention is advantageous for downsizing.

  Further, for example, a groove part through which the lead part passes may be formed in the upper collar part.

  By using the upper collar portion in which such a groove portion is formed, it is possible to easily arrange the lead portion having excellent insulating characteristics as described above. Therefore, the coil component having such an upper collar has excellent productivity. In the present invention, the groove portion is used as a concept including a notch or other concave portion.

  In addition, for example, a convex portion that engages with the lead portion may be formed on the upper collar portion.

  The lead part is pulled up to the upper collar part and then pulled down to the secondary terminal. By engaging the lead part with the convex part formed on the upper collar part, the wiring process of the lead part is easily performed. The coil component having such an upper collar has excellent productivity.

  Further, for example, the convex portion of the upper collar portion may have a locking portion that locks the lead portion.

  When the convex portion has the locking portion, the engagement between the lead portion and the convex portion can be prevented from being unexpectedly released, and the lead portion wiring process can be performed more easily.

  The convex portion may be configured by a base portion that protrudes substantially parallel to the lower flange portion from the upper collar portion, and the locking portion that is connected to the tip of the base portion and projects upward. .

  By forming such a convex portion, it is possible to shorten the wiring distance from when the lead portion is pulled up to the upper collar portion until it is connected to the secondary terminal, and the secondary coil becomes longer. Can be suppressed. Further, since the base portion and the locking portion can be reliably engaged with the lead portion, the upper collar portion having such a convex portion is prevented from being unexpectedly released from the engagement between the lead portion and the convex portion. It can be effectively prevented.

  The upper collar portion may include a plurality of the convex portions arranged substantially in parallel with a groove portion through which the lead portion passes.

  Even when the number of secondary coils wound around the second hollow cylindrical portion increases, for example, when the lead portion connected to the secondary terminal increases, the upper collar portion having a plurality of convex portions is near the terminal. It is possible to avoid contact between the lead portions.

  Further, for example, in the coil according to the present invention, a pair of ferrite core middle legs are respectively inserted into the through holes of the first hollow cylindrical portion from above and below the first hollow cylindrical portion, and the pair of ferrite cores The side legs and the base portion may be assembled so as to cover a part of the case and the bobbin from the outer periphery.

  A coil component having such a ferrite core has a small leakage magnetic flux in the vertical direction (perpendicular to the bobbin substrate), and suppresses the generation of eddy currents in the peripheral members and the accompanying heat and noise. be able to. Moreover, since it is not necessary to arrange | position the aluminum plate etc. for preventing a leakage magnetic flux, it has a suitable heat dissipation characteristic. Furthermore, since the secondary coil is arranged on the outer periphery of the primary coil, the middle leg and the side leg of the core can be shortened, and the strength and impact resistance characteristics of the coil parts are good.

FIG. 1 is an overall perspective view of a coil component according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the coil component shown in FIG. 3 is a cross-sectional view of the coil component corresponding to the cutting plane III shown in FIG. FIG. 4 is a bottom view of the coil component shown in FIG. FIG. 5 is a perspective view of a case used for the coil component according to the second embodiment of the present invention. FIG. 6 is a perspective view of a case used for the coil component according to the third embodiment of the present invention. FIG. 7 is a perspective view of a case used for the coil component according to the fourth embodiment of the present invention. FIG. 8 is an overall perspective view of a coil component according to the fifth embodiment of the present invention.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
First embodiment

  As shown in FIG. 1 which is an overall perspective view and FIG. 2 which is an exploded perspective view, a coil component 10 according to an embodiment of the present invention includes a core 12, a bobbin 40, a case 50, a primary coil 20, A secondary coil 30.

  The core 12 of the coil component 10 forms a magnetic path through which a magnetic flux generated by a coil, which will be described later, passes, and is formed by assembling two first components 12a and 12b that are separately molded. The The first core 12a and the second core 12b have a symmetrical shape, and are joined to each other so as to sandwich the case 50 and the bobbin 40 from the vertical direction (Z-axis direction in each drawing).

  As shown in FIG. 1, the core 12 has a first core 12 a and a second core 12 b each having a substantially E-shaped longitudinal section (cut plane including the X axis and the Z axis). As shown in FIG. 2, each of the cores 12a and 12b is made of a ferrite core, and extends in the X-axis direction. The flat base portions 13a and 13b extend from both ends of the bases 13a and 13b in the X-axis direction. Side legs 16a, 16b, 18a, 18b projecting from each other and middle legs 14a, 14b projecting in the Z-axis direction from intermediate positions in the X-axis direction of the bases 13a, 13b.

  In the drawings, the Z-axis is the height direction of the coil component 10, and the height of the coil component can be reduced as the height of the coil component 10 in the Z-axis direction becomes shorter. In addition, the X axis and the Y axis are perpendicular to each other and perpendicular to the Z axis. In this embodiment, the X axis coincides with the arrangement direction of the secondary terminals 72 and the longitudinal direction of the core 12. The axis coincides with the longitudinal direction of the coil component 10. Moreover, in FIGS. 1-4, description is abbreviate | omitted about the lead part of each coil, and only the part relevant to the structure of invention is displayed with the continuous line or the dotted line.

  As shown in FIG. 2, the bobbin 40 has a substantially flat plate-like bobbin substrate 42. In order to reduce the mounting area, the bobbin substrate 42 according to the present embodiment gradually decreases in width in the X-axis direction from the central portion sandwiched between the cores 12 toward the primary side end where the primary terminal 70 is installed. However, the shape of the bobbin substrate 42 is not limited to this.

  The bottom surface side of the bobbin substrate 42 is an installation surface for the coil component 10. A plurality (two in the illustrated example) of primary terminals 70 are installed at predetermined intervals along the X-axis direction at one end of the bobbin substrate 42 in the Y-axis direction. A plurality (9 in the illustrated example) of secondary terminals 72 are installed at predetermined intervals along the X-axis direction at the other end of the bobbin substrate 42 in the Y-axis direction.

  These terminals 70 and 72 are made of, for example, metal terminals, and are integrally formed by insert molding or the like on the bobbin substrate 42 made of an insulating material such as synthetic resin. As will be described later, the primary lead 70 is connected to the primary lead portion 23 (see FIG. 4) of the primary coil 70, and the secondary terminal 72 is connected to the secondary lead portions 33a and 33b of the secondary coil 30. The

  As shown in FIG. 3 which is a cross-sectional view of FIGS. 2 and 1, a first hollow cylinder portion 44 is disposed at a substantially central position of the bobbin substrate 42. The first hollow cylinder portion 44 protrudes from the bobbin substrate 42 in the Z-axis direction, and the bobbin substrate 42 is connected to the lower end of the first hollow cylinder portion 44. The primary coil 20 is wound around the outer periphery of the first hollow cylinder portion 44. The first hollow cylinder portion 44 functions as a bobbin main body of the primary coil 20.

  A bobbin upper collar 48 a is connected to the upper end of the first hollow cylinder portion 44. The bobbin upper collar 48a has a shape protruding in the radial direction from the first hollow cylindrical portion 44 along the X-axis-Y-axis plane, and has a function of holding the primary coil 20. A bobbin intermediate rod 48b for holding the primary coil 20 and securing an insulating distance is disposed between the bobbin upper rod 48a and the bobbin substrate 42. The bobbin intermediate rod 48b has a shape protruding in the radial direction from the first hollow cylinder portion 44, like the bobbin upper rod 48a. The bobbin substrate 42, the first hollow cylinder portion 44, the bobbin upper collar 48a, and the bobbin intermediate collar 48b are preferably integrally molded by injection molding or the like.

  The bobbin substrate 42, the first hollow cylindrical portion 44, the bobbin upper collar 48a, and the bobbin intermediate collar 48b are formed with through holes 44a penetrating them in the Z-axis direction. The opening shape of the through hole 44a is substantially the same as the opening shape of a through hole 52a formed in the case 50 to be described later, and as shown in FIG. 2, the middle leg in the core 12b (the same applies to 12a). 14b (the same applies to 14a / the same applies hereinafter) has an elliptical shape that can be inserted.

  As shown in FIG. 2, the shape of the inner periphery 21 of the primary coil, which is the inner periphery of the primary coil 20, coincides with the outer periphery of the first hollow cylindrical portion 44 and becomes an elliptical shape. The shape of the primary coil outer peripheral edge 22, which is the outer peripheral edge of the primary coil 20, is an elliptical shape having a major axis and a minor axis larger than the inner peripheral edge 21. As shown in FIG. 3, the outer periphery 22 of the primary coil is configured to fit inside a second hollow cylinder portion 54 of the case 50 described later.

  As shown in FIG. 2, on both side surfaces in the X-axis direction of the bobbin substrate 42, engagement protrusions 49 that are detachably engaged with engagement holes 59a of the case 50 described later are formed.

  The case 50 holds the secondary coil 30 (see FIG. 3 and the like) and defines a part of the outer shape of the coil component 10. As shown in FIG. 3, the case 50 includes a second hollow cylinder portion 54 around which the secondary coil 30 is wound. The second hollow cylinder portion 54 functions as a bobbin main body of the secondary coil 30.

  As shown in FIGS. 2 and 3, the upper collar portion 52 is connected to the upper end of the second hollow cylinder portion 54 in the Z-axis direction. The upper collar part 52 has a shape protruding radially inward and outward from the second hollow cylinder part 54 along the XY axis plane. The upper collar portion 52 is provided to face the bobbin upper collar 48a of the bobbin 40 and extends in parallel with the installation surface.

  As shown in FIG. 2, the upper collar part 52 is formed with a through hole 52a through which the middle leg 14a of the core 12a is inserted. The upper flange 52 is provided with an installation groove 52c for installing the base 13a of the core 12a.

  As shown in FIG. 3, the second hollow cylindrical portion 54 of the case 50 protrudes downward in the Z-axis direction substantially perpendicularly from the lower surface of the upper collar portion 52. The second hollow cylinder portion 54 has a shape that covers the bobbin upper collar 48a and the bobbin intermediate collar 48b shown in FIGS. 2 and 3 from the outer periphery, and in addition to these, the first hollow cylinder portion 44, The primary coil 20 wound around the hollow cylinder portion 44 and the middle leg 14a (14b) inserted through the first hollow cylinder portion 44 are housed inside. In other words, the middle leg 14 a (14 b) passes through the first hollow cylinder part 44 and the second hollow cylinder part 54 disposed on the outer periphery of the first hollow cylinder part 44.

  As shown in FIGS. 2 and 3, a lower collar portion 58 is connected to the lower end of the second hollow cylinder portion 54 in the Z-axis direction. Similarly to the upper collar part 52, the lower collar part 58 has a shape protruding in the radial direction from the second hollow cylinder part 54 along the XY axis plane. The lower collar portion 58 is mounted so as to cover the upper surface of the bobbin substrate 42 of the bobbin 40.

  Side portions 59 projecting downward in the Z-axis direction are formed at both end portions in the X-axis direction of the lower collar portion 58. An engagement hole 59 a that engages with the engagement protrusion 49 of the bobbin 40 is formed in the side surface portion 59.

  As shown in FIG. 3, on the outer peripheral surface of the second hollow cylindrical portion 54 located between the upper flange portion 52 and the lower flange portion 58, the secondary coil 30 is divided and arranged along the Z-axis direction. One or more intermediate flanges 56 are provided depending on the application of the coil component 10 or the like. These flanges 52, 56, and 58 are parallel along the XY axis plane. The case 50 composed of the flange portions 52, 56, 58 and the second hollow cylinder portion 54 is integrally formed by injection molding or the like. As shown in FIG. 3, the coil component 10 has a double structure in which the primary coil 20 and the secondary coil 30 double around the middle leg 14 a (14 b) of the core 12 a (12 b). .

  As shown in FIG. 2, the shape of the secondary coil inner peripheral edge 31, which is the inner peripheral edge of the secondary coil 30, matches the outer peripheral shape of the second hollow cylinder portion 54, and becomes an ellipse or a circular shape. Although the secondary coil 30 according to the present embodiment is configured by two independent coils, the secondary coil 30 may be configured by one coil or may be configured by three or more coils.

  As shown in FIG. 1, the upper collar portion 52 of the case 50 is formed with an upper collar convex portion 53 that engages with the lead portions 33 a and 33 b of the secondary coil 30. The upper collar convex portion 53 is formed at one end of the upper collar 52 in the Y-axis direction (end in the Y-axis positive direction). The upper collar portion 52 is formed with a plurality of upper collar convex portions 53, and the plurality of upper collar convex portions 53 are arranged substantially in parallel with the upper collar groove portion 52b through which the lead portions 33a and 33b pass. ing.

  As shown in FIG. 1 and FIG. 3, the upper collar convex portion 53 is connected to the base 53b that is substantially parallel to the lower collar 58 and protrudes in the Y-axis direction, and the tip of the base 53b. It is comprised by the latching | locking part 53a which protrudes in a Z-axis positive direction). Of the lead portions of the secondary coil 30, the lead portions 33 a and 33 b are pulled up from the second hollow cylinder portion 54 to the height of the upper surface of the upper flange portion 52 (in the positive Z-axis direction), and then to the secondary terminal 72. Connected.

  As shown in FIG. 1, the upper gutter groove part 52b formed between the upper gutter convex parts 53 has penetrated in the up-down direction. The lead portions 33a and 33b drawn out from the second hollow cylinder portion 54 are routed from the lower side to the upper side through the upper eaves groove portion 52b to the upper surface of the upper eave portion 52, and are engaged with the upper eaves convex portion 53. After joining, this time, it passes through the upper groove portion 52b from the upper side to the lower side, and is led to the secondary terminal 72. The engaging portion 53a provided at the tip of the upper collar convex portion 53 in the Y-axis direction releases the engagement between the lead portions 33a and 33b and the upper collar convex portion 53, and the lead portion 33a falls off the upper collar convex portion 53. To prevent that.

  Further, the intermediate flange portion 56 and the lower flange portion 58 of the case 50 are extended to the vicinity of the end portion of the bobbin substrate 42 where the secondary terminal 72 is installed. The intermediate groove portion 56b and the lower flange portion 58b for guiding the lead portions 33a and 33b of the secondary coil 30 to the secondary terminal 72 are arranged along the X-axis direction. Further, the substrate groove portion 47 for guiding the lead portions 33 a and 33 b of the secondary coil 30 to the secondary terminal 72 is also formed on the bobbin substrate 42 of the bobbin 40. After the lead portions 33a and 33b are pulled out from the second hollow cylinder portion 54 and engaged with the upper flange convex portion 53, the lead portions 33a and 33b pass through the intermediate groove portion 56b, the lower flange portion 58b, and the substrate groove portion 47 to the secondary terminal 72. Connected. Further, among the lead portions of the secondary coil 30, the other lead portions that do not engage with the upper flange convex portion 53 are pulled out from the second hollow cylinder portion 54, and then the intermediate groove portion 56 b, the lower flange groove portion 58 b, and the substrate groove portion. 47 and connected to the secondary terminal 72.

  In this embodiment, the intermediate groove portion 56b, the lower collar groove portion 58b, and the substrate groove portion 47 are formed corresponding to the number and positions of the gaps between the secondary terminals 72 and the secondary terminals 72 that are adjacent to each other. There is no need. Further, the upper flange 53 is formed corresponding to the number and position of the gaps between the adjacent intermediate groove 56b (the same applies to the lower flange 58 and the substrate groove 47) and the intermediate flange 56. There is no need to let them. Since it is not necessary to engage all of the lead portions of the secondary coil 30 with the upper hook convex portion 53, only the upper hook convex portion 53 with which the lead portions 33a and 33b are actually engaged may be formed. Further, in order to flexibly cope with a design change or the like related to terminal arrangement or the like, as shown in FIG. 1, an upper collar convex portion 53 to which the lead portion of the secondary coil 30 is not engaged may be formed.

  The coil component 10 according to the present embodiment is created by assembling the members shown in FIG. 2 and winding a wire around the bobbin 40 and the case 50. Below, an example of the manufacturing method of the coil component 10 is demonstrated using FIG. In creating the coil component 10, first, the bobbin 40 to which the primary terminal 70 and the secondary terminal 72 are attached is prepared. The material of the bobbin 40 is not particularly limited, but the bobbin 40 is formed of an insulating material such as resin.

  Next, a winding is wound around the first hollow cylinder portion 44 of the bobbin 40 to form the primary coil 20. Although it does not specifically limit as a winding used for formation of the primary coil 20, A litz wire etc. are used suitably. Moreover, the primary lead part 23 which is the terminal part of the winding at the time of forming the primary coil 20 is entangled and connected to the primary terminal 70 through the communication path 46 of the bobbin 40 (see FIG. 3 etc.).

  Next, the case 50 shown in FIG. 2 is attached to the bobbin 40 on which the primary coil 20 is formed. The case 50 and the bobbin 40 are assembled by engaging the engagement hole 59a of the case 50 with the engagement protrusion 49 of the bobbin 40. The case 50 and the bobbin 40 are fixed by adhesion or the like as necessary. The material of the case 50 is not particularly limited, and is formed of an insulating material such as resin.

  Next, a winding is wound around the second hollow cylinder portion 54 of the case 50 to form the secondary coil 30. Although it does not specifically limit as a winding used for formation of the secondary coil 30, A litz wire etc. are used suitably. A part of the lead portion (lead portions 33a and 33b in FIG. 1) which is the end portion of the winding when the secondary coil 30 is formed is pulled up to the height of the upper surface of the upper collar portion 52 and the upper collar convex portion 53 After being engaged with each other, the intermediate groove portion 56b, the lower flange portion 58b, and the substrate groove portion 47 are passed through, and finally wound around the secondary terminal 72. In addition, the other part of the lead portion passes through the intermediate groove portion 56b, the lower flange groove portion 58b, the substrate groove portion 47, and the like from the second hollow cylinder portion 54 without being pulled up to the upper flange convex portion 53. Then, it is wound around the secondary terminal 72. The upper coil groove part 52b, the upper coil convex part 53, the intermediate groove part 56b, the lower coil groove part 58b, and the substrate groove part 47 facilitate the winding work of the secondary coil 30, and facilitate the automation of the work.

  In addition, since the adjacent lead portions pass through the intermediate groove portion 56b, the lower groove portion 58b, and the substrate groove portion 47, it is possible to suitably secure an insulation distance, and the insulation properties between adjacent lead portions are also good. To be kept. Further, the lead portions 33a and 33b are once pulled up to the height of the upper surface of the upper collar portion 52 and engaged with the upper collar convex portion 53, so that the lead portions contact each other in the vicinity of the secondary terminal 72. This can be suitably avoided. Therefore, for example, a plurality of mutually separated coils are arranged in the second hollow cylinder portion 54 (see FIG. 3) to form the secondary coil 30, and many lead portions are connected from the second hollow cylinder portion 54 to the secondary terminal 72. Even in the case of wiring up to, it is possible to maintain good insulation between the lead portions. However, since the secondary coil 30 is configured by a lead wire whose core wire is covered with insulation, it does not prevent a portion of the lead portion from contacting or intersecting with another lead portion.

  Next, the first core 12a and the second core 12b of the core 12 are attached to the intermediate assembly in which the primary coil 20, the secondary coil 30, the case 50, and the bobbin 40 are combined from above and below in the Z-axis direction. The core 12 is formed. That is, the tips of the middle legs 14a, 14b of the first core 12a and the second core 12b, the tips of the side legs 16a, 16b, and the tips of the side legs 18a, 18b are joined. A gap may be provided between the tips of the middle legs 14a and 14b.

  Examples of the material of the core 12 include soft magnetic materials such as metal and ferrite, but are not particularly limited. The first core 12a and the second core 12b of the core 12 are fixed to the case 50 and the bobbin 40 by being bonded using an adhesive or by winding the outer periphery with a tape. In addition, the varnish impregnation process may be performed with respect to the coil component 10 after a series of assembly processes. The coil component 10 according to the present embodiment can be manufactured through the steps as described above.

  As shown in FIG. 3, the coil component 10 is a vertical type in which the Z-axis direction (direction in which the magnetic flux flows) of the middle legs 14 a (14 b) is perpendicular to the installation surface. As shown in FIGS. 1 and 3, the vertical coil component 10 has base portions 13a and 13b of the core 12 arranged in the vertical direction of the Z axis of the primary and secondary coils 20 and 30, and these base portions 13a. , 13b has an effect of suppressing leakage magnetic flux in the vertical direction. Therefore, the coil component 10 can suppress the leakage magnetic flux in the vertical direction of the coil component 10 as compared with the horizontal type in which the vertical direction of the coil is hardly shielded by the core.

  As shown in FIG. 3, the coil component 10 has a double structure in which the secondary coil 30 goes around the outer periphery of the primary coil 20. By adopting a double structure, the coil component 10 can shorten the axial length of the core 12 and realize a thin coil while being a vertical type.

  With the arrangement of the core as described above, the coil component 10 can prevent the generation of eddy currents in the surrounding structural material and the like without providing an aluminum shielding plate or the like. Further, by preventing the generation of eddy current, the coil component 10 can reduce the generation of heat and noise accompanying the generation of eddy current. Moreover, since the coil component 10 does not need to be provided with a shielding plate for shielding leakage magnetic flux, the coil component 10 has good heat dissipation characteristics. Furthermore, since the length of the middle legs 14a, 14b and the side legs 16a, 16b, 18a, 18b of the core 12 is short, the coil component 10 can prevent damage to the core 12 due to external impacts or the like.

  In the present embodiment, since the primary terminal 70 and the secondary terminal 72 are formed on the bobbin substrate 42, it is not necessary to provide terminals on the case 50. For this reason, it becomes possible to design the shape of the case 50 freely, the degree of freedom of design is increased, the reduction in height is facilitated, and the resin is relatively inexpensive as the case 50 compared to the bobbin 40. The manufacturing cost can be reduced. Note that the bobbin 40 on which the terminals 70 and 72 are formed is required to have heat resistance for soldering to the terminals 70 and 72.

  Further, as shown in FIG. 1, some of the lead portions 33 a and 33 b are pulled up to the upper collar portion 52 and then connected to the secondary terminal 72, so that, for example, the intermediate collar portion 56 and the lower collar portion 58 are connected. It is possible to avoid that the lead portions come into contact with each other at a position close to the secondary terminal 72 like the surface. In particular, when the secondary terminal 72 and the end of the lead portion are connected through a heating process such as soldering, the insulating coating of the lead portion may be thermally damaged in the vicinity of the secondary terminal 72. is there. Therefore, it is preferable from the viewpoint of ensuring insulation that the lead wires are not in contact with each other in the vicinity of the secondary terminal 72. Further, by arranging the lead portions in this way, it is possible to perform wiring within a narrow range while ensuring insulation, and thus the coil component 10 is advantageous for downsizing.

Second Embodiment FIG. 5 is a perspective view of a case 50a used for a coil component according to a second embodiment of the present invention. The coil component according to the second embodiment is the same as the coil component 10 according to the first embodiment, except that the shape of the upper collar protrusion 81 in the case 50a is different. Unlike the upper ridge protrusion 53 shown in FIG. 1, the upper ridge protrusion 81 does not have a locking portion 53 a, but by appropriately securing a protruding length in the Y-axis direction, It is possible to prevent the engaging lead portions 33a and 33b from falling off. The coil component according to the second embodiment also has the same effect as the coil component according to the first embodiment.

Third Embodiment FIG. 6 is a perspective view of a case 50b used for a coil component according to a third embodiment of the present invention. The coil component according to the third embodiment is the same as the coil component 10 according to the first embodiment, except that the shape of the upper collar protrusion 82 in the case 50b is different. The upper collar convex portion 82 has an upper groove portion 82c that opens upward, and a locking portion 82a that is connected to the tip side from the upper groove portion 82c. When engaging the lead portions 32a and 32b with the upper flange portion 82, the lead portions 33a and 33b can be prevented from falling off by passing through the upper groove portion 82c, and the positions of the lead portions 33a and 33b can be adjusted. It can be stabilized. The coil component according to the third embodiment also has the same effect as the coil component according to the first embodiment.

Fourth Embodiment FIG. 7 is a perspective view of a case 50c used for a coil component according to a fourth embodiment of the present invention. The coil component according to the fourth embodiment is the same as the coil component 10 according to the first embodiment, except that the shapes of the upper collar protrusion 86 and the upper collar grooves 87a, 87b in the case 50c are different. The upper flange portions 87 a and 87 b of the case 50 c are formed on the outer peripheral edge portion 85 of the upper flange portion 84. That is, an outer peripheral edge 85 protruding upward from the flat plate portion 84a is formed on the outer peripheral portion of the upper flange portion 84 except for a portion through which the core 12 passes, and the upper flange portions 87a and 87b are formed on the outer peripheral edge portion. A part of 85 is cut out.

  Between the two upper hook groove portions 87a and 87b, an upper hook convex portion 86 with which the lead portion 33c of the secondary coil is engaged is formed. Unlike the upper ridge protrusion 53 according to the first embodiment, the upper ridge protrusion 86 protrudes upward (Z-axis direction) from the upper flange 84. The case 50c used in the fourth embodiment has a simpler shape and is easier to manufacture than the cases 50, 50a, 50b used in the first to third embodiments. Moreover, the coil component which concerns on 4th Embodiment also has the same effect as the coil component which concerns on 1st-3rd Embodiment.

Fifth Embodiment FIG. 8 is an overall perspective view of a coil component 10a according to a fifth embodiment of the present invention. The coil component 10a according to the fifth embodiment is the same as the coil component 10 according to the first embodiment except that the shapes of the lower flange portion 88 and the bobbin substrate 92 of the case 50d on the primary terminal 70 side from the core 12 are different. is there. As shown in FIG. 8, the shapes of the case 50d and the bobbin substrate 92 on the primary terminal 70 side from the core 12 are not particularly limited, and can be appropriately changed in consideration of ease of handling in the mounting process, mounting area, and the like. . The coil component 10a according to the fifth embodiment also has the same effect as the coil component according to the first to fourth embodiments.

  In the above-described embodiment, the cross-sectional shape of the middle leg 14a (14b) of the core 12 is an ellipse, but the cross-sectional shape of the middle leg 14a (14b) is not particularly limited, and other shapes such as a circle, a polygon, and the like. It may be. Moreover, it is not specifically limited about the winding shape of the primary coil 20 and the secondary coil 30, Other shapes, such as a circle | round | yen and a polygon, may be sufficient.

  In addition, the names of “primary” and “secondary” for the coil, lead wire, and terminal are convenient, and in the present invention, the coil mounted on the bobbin 40 is referred to as a primary coil, and the coil mounted on the case. Is referred to as a secondary coil, and the primary coil is not necessarily on the input side, the primary coil may be on the output side, and the secondary coil may be on the input side.

DESCRIPTION OF SYMBOLS 10,10a ... Coil components 12 ... Core 12a, 12b ... 2nd core 13a, 13b ... Base part 14a, 14b ... Middle leg 16a, 16b, 18a, 18b ... Side leg 20 ... Primary coil 30 ... Secondary coil 33a, 33b , 33c ... lead part 40 ... bobbin 42, 92 ... bobbin substrate 44 ... first hollow cylinder part 48a ... bobbin upper collar 48b ... bobbin intermediate collar 49 ... engagement protrusion 50, 50a, 50b, 50c, 50d ... case 52, 84 ... Upper collar part 44a, 52a ... Through hole 52b, 87a, 87b ... Upper collar groove part 52c ... Installation groove part 53,81,82,86 ... Upper collar convex part 53a, 82a ... Locking part 53b ... Base part 54 ... Second hollow Tube portion 56 ... Intermediate flange portion 56b ... Intermediate groove portion 58, 88 ... Lower flange portion 58b ... Lower flange portion 70 ... Primary terminal 72 ... Secondary terminal

Claims (7)

A first hollow cylinder part around which the primary coil is wound, a primary terminal that connects the primary coil, and a secondary terminal that connects the secondary coil are installed and connected to the lower end of the first hollow cylinder part A bobbin substrate having a bobbin substrate,
A second hollow cylinder part that can be attached to the outer periphery of the primary coil and the secondary coil is wound around the outer periphery, and a lower end of the second hollow cylinder part that is attached to the upper surface of the bobbin substrate. A case having a lower collar part and an upper collar part connected to the upper end of the second hollow cylinder part;
A coil component comprising:
At least one lead part in the secondary coil is connected to the secondary terminal after being pulled up from the second hollow cylinder part to the upper collar part.   The coil component according to claim 1, wherein a groove portion through which the lead portion passes is formed in the upper collar portion.   3. The coil component according to claim 1, wherein a convex portion with which the lead portion is engaged is formed on the upper collar portion.   The coil component according to claim 3, wherein the convex portion of the upper collar portion has a locking portion that locks the lead portion.   The convex portion includes a base portion that protrudes substantially parallel to the lower flange portion from the upper flange portion, and a locking portion that is connected to the tip of the base portion and protrudes upward. The coil component according to claim 4.   6. The coil component according to claim 4, wherein the upper collar portion has a plurality of the convex portions arranged substantially in parallel with a groove portion through which the lead portion passes. 6.   Middle legs of a pair of ferrite cores are inserted into the through holes of the first hollow cylinder part from above and below the first hollow cylinder parts, respectively, and the side legs and base parts of the pair of ferrite cores are the case and The coil component according to any one of claims 1 to 6, wherein the coil component is assembled so as to cover a part of the bobbin from the outer periphery.

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