JP2016134590A - Coil device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coil device which allows for strong and reliable wire connection processing, while reducing damage on a magnetic core.SOLUTION: Terminal electrodes 60, 70 have rising pieces 62 for wire connection to be raised integrally from one end of an attachment piece 61 in the longitudinal direction along the side face of a flange in the X axis direction, and a connection piece formed integrally on the upper end side of the rising pieces for wire connection, and where weld balls to which the leads 12a, 12b of a wire are connected by laser welding are formed. Laser shield members 63, 73 are disposed between the weld balls 68a, 78a and the flange 40 of a drum core 20.SELECTED DRAWING: Figure 1A

Description

  The present invention relates to a coil device, and more particularly to a coil device that can perform a strong and reliable wire connection process and that causes little damage to a magnetic core.

  In order to reduce the thickness, for example, a drum core and a terminal shape as shown in Patent Document 1 below are well known. However, in the coil device disclosed in Patent Document 1, the lead portion of the wire for winding is soldered to the terminal electrode.

  For this reason, for example, when soldering when mounting the terminal electrode on the circuit board, there is a problem that the connection between the lead portion of the wire for winding and the terminal electrode tends to be insufficient due to the heat. doing. In particular, in order to make the device compact and the like, when the connection portion between the lead portion and the terminal electrode is close to the mounting surface, the connection between the lead portion and the terminal electrode tends to be insufficient.

  Therefore, it has been studied to connect the lead portion of the wire for winding and the terminal electrode by laser welding. However, the magnetic core may be damaged by laser light and its reflection during laser welding. As damage to the magnetic core, breakage, cracking or chipping of the core due to thermal shock can be considered.

  A coil device as shown in Patent Document 2 below is also known. In this coil device, a connection piece for tying a lead end of a wire protrudes outward from the coil device. The protruding portion may contact a device such as a mounter in the process of transporting to the mounting machine, etc., and may break due to the impact or stress, and may damage the core.

  Also, in order to reduce the size of the device, if a binding terminal that is not considered for laser welding of the lead end is placed near the magnetic core and laser welding is performed on the binding terminal as it is, the laser is still used. There is a risk that the magnetic core may be damaged by the laser beam or its reflection during welding.

WO2009 / 034860 Utility Model Registration No. 3171315

  The present invention has been made in view of such a situation, and an object of the present invention is to provide a coil device that can perform a strong and reliable wire connecting process and that has little damage to a magnetic core.

In order to achieve the above object, a coil device according to the present invention comprises:
A magnetic core having a core portion around which a wire is wound so as to form a coil;
A coil device having a terminal electrode attached to an outer end surface in the winding axis direction of the collar portion formed at an end portion in the winding axis direction of the core portion,
The terminal electrode is
A mounting piece in contact with the outer end surface in the winding axis direction of the flange,
From one end in the longitudinal direction of the attachment piece, a rising piece for connection that is integrally raised along the first axial direction side surface of the flange,
A connection piece formed integrally with the upper end side of the connection rising piece, and formed with a weld ball to which the lead portion of the wire is connected by laser welding,
A laser shielding member is disposed between the weld ball and the magnetic core.

  In the coil device according to the present invention, the lead portion of the wire for winding and the terminal electrode are connected by laser welding. Therefore, a strong and reliable wire connection process is possible.

  In the coil device of the present invention, since a laser shielding member is disposed between the connection piece on which the weld ball is to be formed and the magnetic core, the laser beam or reflected light is emitted during laser welding. The magnetic core is not irradiated. Therefore, even if the device is made compact and the connecting piece is arranged near the magnetic core, there is no possibility that the magnetic core is damaged by the laser beam or its reflection during laser welding. Therefore, the core is not damaged, cracked or chipped by thermal shock.

  Preferably, the shielding member is held in a space between the weld ball and the magnetic core. By comprising in this way, it becomes difficult to transmit the thermal influence of the laser beam at the time of the said welding ball being made to a magnetic core, and the damage of a magnetic core can further be reduced.

  Preferably, the shielding member is formed integrally with the terminal electrode. By comprising in this way, it becomes unnecessary to prepare a shielding member separately and it contributes to reduction of a number of parts. The shielding member may be made of ceramic, metal, or the like, and may be attached only to a necessary portion of the magnetic core or may be integrally formed.

  Preferably, the lead connecting portion made of the weld ball is formed within the thickness range of the flange portion. By adopting such a configuration, the coil device can be made compact.

  Preferably, the periphery of the core portion around which the wire is wound is covered with an exterior resin. By being covered with the exterior resin, the coil portion can be effectively protected, and short-circuit defects and the like can be suppressed. Moreover, it is preferable that exterior resin is comprised with magnetic body containing resin. By comprising in this way, the exterior resin containing a magnetic substance becomes a path of a magnetic field, and the magnetic characteristic of a coil apparatus improves.

  Preferably, a temporary fixing piece for temporarily fixing the lead portion of the wire is integrally formed on the upper end side of the connection rising piece separately from the connection piece. By forming the temporary fixing piece, the laser welding operation is facilitated.

  Preferably, on the side surface in the first axial direction of the flange portion, an upright piece facing plane that positions the connecting piece facing the upright piece for connection, and a concave inward from the upright piece facing plane And a terminal gap recess for forming a gap with the formation rising piece. By comprising in this way, the connection piece of a terminal electrode is positioned favorably with respect to the collar part of a magnetic core, and the lead end of a wire can be reliably connected to a terminal electrode by laser irradiation.

  Further, the recess for the terminal gap alleviates the thermal shock when laser welding the lead end of the wire to the connecting portion of the terminal electrode, and can effectively prevent the core from being damaged, cracked, or chipped. In addition, since there is a gap between the side surface of the buttock and the rising piece for connection, external force acting on the terminal electrode is absorbed, and it is possible to effectively prevent wire breakage or core breakage due to external force. it can. Furthermore, since there is a gap between the side surface of the flange portion and the connecting electrode rising piece, the heat dissipation is excellent.

  Preferably, in order to connect the tip of the lead portion of the wire and the connection piece, from the direction intersecting the first axial side surface, toward the tip of the connection piece and the lead portion of the wire, The shielding member that shields the laser beam from being irradiated onto the magnetic core when the laser beam is irradiated is formed integrally with the connecting rising piece. By comprising in this way, formation of a shielding member becomes easy.

FIG. 1A is a perspective view of a coil device according to an embodiment of the present invention. 1B is a front view of the coil device shown in FIG. 1C is a right side view of the coil device shown in FIG. 1 (the left side view is symmetrical to the right side view). FIG. 1D is a rear view of the coil device shown in FIG. FIG. 1E is a plan view of the coil device shown in FIG. FIG. 1F is a bottom view of the coil device shown in FIG. FIG. 2 is a schematic sectional view taken along line II-II shown in FIG. 1A. FIG. 3 is a cross-sectional perspective view taken along line III-III shown in FIG. 4 is a cross-sectional perspective view taken along the line IV-IV shown in FIG. FIG. 5 is an exploded perspective view of the coil device shown in FIG. FIG. 6 is an enlarged perspective view of the terminal electrode shown in FIG. FIG. 7 is a perspective view showing the manufacturing process of the coil device shown in FIG. FIG. 8 is a perspective view showing a step subsequent to FIG. FIG. 9 is a perspective view showing a step subsequent to FIG.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
A coil device 2 according to an embodiment of the present invention shown in FIGS. 1A to 1F is used as, for example, a choke coil, a noise filter, and the like, and particularly preferably a coil device used for in-vehicle use.

  As shown in FIG. 2, the coil device 2 includes a drum core 20 as a magnetic core. Examples of the magnetic material constituting the drum core 20 include, but are not particularly limited to, soft magnetic materials such as metal and ferrite. The drum core 20 includes a winding core 30 in which a wire 12 constituting the coil 10 is wound along the winding axis direction of the core 20.

  It is preferable that the periphery of the core portion 30 around which the wire 12 is wound is covered with the exterior resin 15. By being covered with the exterior resin 15, the coil portion 10 can be effectively protected, and short-circuit defects can be suppressed. The exterior resin 15 is preferably composed of a magnetic substance-containing resin. By comprising in this way, the magnetic body containing exterior resin 15 becomes a path of a magnetic field, and the magnetic characteristic of the coil apparatus 2 improves. Although it does not specifically limit as a magnetic body contained in the exterior resin 15, The magnetic body powder similar to the magnetic body powder which comprises the core 20, or another magnetic body powder is illustrated.

  The wire 12 is not particularly limited, and is, for example, a conductive wire such as a flat wire, a round wire, a stranded wire, a litz wire, a braided wire, or the like formed of copper or the like, or a wire in which these conductive wires are covered with insulation. Etc. can be used. Specifically, known windings such as AIW (polyimide wire), UEW (polyurethane wire), UEW, and USTC can be used. The wire diameter of the wire 12 is not specifically limited, For example, it is 0.1-0.5 mm.

  A first flange portion 40 and a second flange portion 50 are integrally formed at both ends of the winding core portion 30 in the winding axis direction (Z-axis direction). The first flange part 40 and the second flange part 50 protrude in the XY axis plane with respect to the core part 30. Note that the X axis, the Y axis, and the Z axis are perpendicular to each other, and the Z axis coincides with the axial direction of the winding axis.

  The cross section (cross section of the XY axis plane) of the core part 30 is not particularly limited, and may be a square cross section, a rectangular cross section, a circular cross section, or other cross sectional shapes. As shown in FIG. 3, it is substantially circular.

  As shown in FIG. 2, the second flange 50 has a second axial outer end surface 52 and a second axial inner surface 53 located on the opposite side. The upper end in the Z-axis direction of the coil portion 10 is positioned on the second axial inner surface 53. In FIG. 2, the coil 12 is formed by double-winding the wire 12 around the core 30, but the number of winding layers is not particularly limited, and the winding is wound more than twice. May be. Moreover, the winding method of the wire 12 is not particularly limited.

  In the present embodiment, as shown in FIG. 1F, the planar shapes of the first collar part 40 and the second collar part 50 are different from each other, and the outer size of the second collar part 50 is the outer dimension of the first collar part 40. Greater than size. The specific planar shape of the second flange portion 50 is not particularly limited, but in the present embodiment, as shown in FIG. 1E, it has a rectangular shape as a whole, and R portions 54 are formed at four corner portions, respectively. It is. The R portion 54 is integrally formed with the first flange portion 40, the second flange portion 50, and the core portion 30 when the drum core 20 shown in FIG. 5 is formed. However, after the integral formation, the R portion 54 is cut or polished. It may be formed.

  As shown in FIG. 1E, the planar shape of the second flange 50 is such that when the drum core 20 is viewed in the Z-axis direction from the second axially outer end surface 52 of the second flange 50, the first flange 40 is It is the shape which is located inside the 2nd collar part 50 and cannot be seen.

  As shown in FIG. 2, the first flange 40 has a winding-axis direction outer end surface 42 and a winding-axis direction inner surface 43 located on the opposite side. The lower end in the Z-axis direction of the coil portion 10 is positioned on the inner surface 43 in the winding axis direction. The first terminal electrode 60 and the second terminal electrode 70 are bonded to both ends in the Y-axis direction on the outer end surface 42 in the winding axis direction of the first flange portion 40 with an adhesive or the like.

  The first terminal electrode 60 and the second terminal electrode 70 each have a symmetrical shape with respect to the X axis, and the details thereof will be described later. For example, they are conductive materials such as tough pitch steel, phosphor bronze, brass, iron and nickel. It is made of a reactive metal.

  The specific planar shape of the first collar 40 is not particularly limited, but in the present embodiment, as shown in FIGS. 1F and 4, the center of gravity is substantially the same as the second collar 50 in the XY axis plane. (It is substantially the same as the core part 30). In addition, the first flange portion 40 has a shape having notches 44 that are largely recessed at the four corner portions as compared with the four corner portions of the second flange portion 50.

  As shown in FIG. 5, the maximum width Ly1 in the Y-axis direction of the first collar portion 40 is substantially the same as or less than the maximum width Ly2 of the second collar portion 50 in the Y-axis direction. The both side surfaces 40a in the Y-axis direction substantially coincide with the both side surfaces 50a in the Y-axis direction of the second flange 50 or are recessed in the Y-axis direction.

  Further, the maximum width Lx1 in the X-axis direction of the first flange portion 40 is substantially the same as or less than the maximum width Lx2 in the X-axis direction of the second flange portion 50, and both sides of the first flange portion 40 in the X-axis direction. The surface 40b is retracted in the X-axis direction at the portion corresponding to the notch 44 except for the central portion in the Y-axis direction with respect to both side surfaces 50b in the X-axis direction of the second flange portion 50.

  As shown in FIG. 4, trapezoidal convex portions 40 b 1 projecting outward in the X-axis direction at the center portion in the Y-axis direction are formed on both side surfaces 40 b in the X-axis direction of the first flange portion 40. Further, each concave portion 44 is formed with rising piece facing flat surfaces 45a and 45b or opposite flat surfaces 46a and 46b, and terminal gap concave portions 47a and 47b or opposite concave portions 48a and 48b recessed inwardly from these. It is. The relationship between the flat surfaces 45a, 45b, 46a, 46b, the recesses 47a, 47b, 48a, 48b, and the terminal electrodes 60, 70 will be described later.

  As shown in FIGS. 5 and 6, the first terminal electrode 60 and the second terminal electrode 70 have plate-like attachment pieces 61 and 71 that are elongated in the X-axis direction, respectively. As shown in FIG. 2, these attachment pieces 61 and 71 are respectively bonded to both ends in the Y-axis direction of the winding-end direction outer end surface 42 of the first flange 40 by an adhesive or the like. A terminal mounting groove that matches the shape of the mounting pieces 61 and 71 may be formed on the outer end face 42 of the first flange 40 to which the mounting pieces 61 and 71 are bonded.

  The groove depth of the terminal mounting groove is preferably smaller than the thicknesses of the mounting pieces 61 and 71, and the bottom surfaces of the mounting pieces 61 and 71 preferably protrude beyond the outer end surface 42 in the winding axis direction. . By doing in this way, the mounting operation | work at the time of connecting the attachment pieces 61 and 71 of the coil apparatus 2 to electrode patterns, such as a circuit board, becomes easy.

  As shown in FIG. 5 and FIG. 6, the connecting rising pieces 62 and 72 are integrally formed at one end in the X-axis direction of the mounting piece 61 and the mounting piece 71 so as to rise in the Z-axis direction, respectively. A rising piece is not formed on the other end.

  As shown in FIG. 4, the rising pieces 62 and 72 can come into contact with the rising piece facing flat surfaces 45 a and 46 a formed on one side surface 40 b of the first flange 40, respectively. A gap is formed between the concave portions 47a and 48a. The terminal electrodes 60 and 70 are not engaged with each other on the opposite flat surfaces 45b and 46b and the opposite concave portions 47b and 48b formed on the other side surface 40b of the first flange 40.

  The first terminal electrode 60 is positioned in the X-axis direction with respect to the first flange portion 40 by the connection rising piece 62 contacting the rising piece facing flat surface 45a. The first terminal electrode 60 is preferably made of a conductive metal and has a spring property. There may be a slight gap between the rising piece facing flat surface 45a and the connecting rising piece 62.

  Similarly, the second terminal electrode 70 is positioned in the X-axis direction with respect to the first flange portion 40 by bringing the rising pieces 72 into contact with the rising piece facing flat surface 46a. The second terminal electrode 70 is preferably made of a conductive metal and has a spring property. There may be a slight gap between the rising piece facing flat surface 46 a and the rising piece 72.

  At the upper ends in the Z-axis direction of the connecting stand-up pieces 62 and 72 formed at one end in the X-axis direction of the mounting pieces 61 and 71, grip pieces 64 and 74 as connecting portions are integrally formed, respectively. It is. As shown in FIG. 3, these gripping pieces 64 and 74 are substantially flush with the winding shaft direction inner surface 43 of the first flange 40 (or lower than it in the Z axis direction), 72 is formed by being bent.

  As shown in FIG. 1A, the gripping piece 64 as the connecting portion includes a temporary fixing piece 65 and a connection piece 66. The temporary fastening piece 65 is located on the inner side in the Y-axis direction with respect to the connection piece 66 and is located at a position close to the trapezoidal convex portion 40b1 located at the center of the X-axis direction side surface 40b of the first flange portion 40. A gap through which the lead portion 12a of the wire 12 can pass is formed between the trapezoidal convex portion 40b1 and the temporary fixing piece 65. A slit 67 extending in the X-axis direction and the Z-axis direction is formed between the temporary fixing piece 65 and the connection piece 66. The Y-axis direction width of the slit 67 is not particularly limited, but is preferably 0.1 to 0.5 mm.

  The temporary fixing piece 65 sandwiches the lead portion 12a, which is one end of the wire 12, between the connecting rising pieces 62 and temporarily fixes it before laser welding of the lead portion 12a described later. The connecting piece 66 sandwiches the lead portion 12a, which is one end of the wire 12, between the connecting rising pieces 62, and at the lead connecting portion 68a formed on the outer side in the Y-axis direction. Integrated and electrically connected to the lead portion 12a.

  As shown in FIGS. 5 to 9, a wide portion 68 wider than the base end portion is formed at the tip of the connection piece 66 before the lead connection portion 68 a is formed. Is mainly the lead connection portion 68a. However, the wide portion 68 is not necessarily formed. Further, in this embodiment, the Y-axis direction width of the temporary fixing piece 65 and the Y-axis direction width of the connection piece 66 are substantially equal, but may be different depending on the wire diameter of the lead portion 12a of the wire 12 and the like.

  Similarly, the holding piece 74 is provided with a temporary fixing piece 75 and a connection piece 76. A slit 77 extending in the X-axis and Z-axis directions is formed between the temporary fixing piece 75 and the connection piece 76. The width of the slit 77 in the Y-axis direction is the same as that of the slit 67, but may not necessarily be the same and may be different.

  A wide portion 78 wider than the base end portion is also formed at the distal end of the connecting piece 76 before the lead joint portion 78a is formed, and this portion mainly becomes the lead connecting portion 78a. However, the wide portion 78 is not necessarily formed. In the present embodiment, the Y-axis direction width of the temporary fixing piece 75 and the Y-axis direction width of the connection piece 76 are substantially equal, but may be different according to the wire diameter of the lead portion 12b of the wire 12 and the like.

  As shown in FIG. 4, a shielding piece 63 as a shielding member is integrally formed on the outer side of the connection rising piece 62 in the Y-axis direction. The shielding piece 63 has substantially the same Z-axis direction width as that of the connection rising piece 62. Further, the tip end of the shielding piece 63 in the Y-axis direction is bent in the X-axis direction toward the terminal gap recess 47a, and is substantially flush with the one side surface 40a in the Y-axis direction of the first flange portion 40. It is preferable. This is to achieve both the shielding effect of the laser beam by the shielding piece 63 as described later and the compactness of the apparatus.

  Note that the tip end of the shielding piece 63 in the Y-axis direction may slightly protrude outward in the Y-axis direction from the side surface 40a in the Y-axis direction of the first flange portion 40, or may be slightly retracted inward in the Y-axis direction. May be. The end of the bent shielding piece 63 enters the terminal gap recess 47a of the first flange 40, but does not come into contact with the drum core 20 including the first flange 40.

  A shielding piece 73 similar to the shielding piece 63 is also integrally formed on the outside of the connecting rising piece 72 in the Y-axis direction. The shielding piece 73 has substantially the same Z-axis direction width as the connection rising piece 72. The tip end of the shielding piece 73 in the Y-axis direction is bent in the X-axis direction toward the terminal gap recess 48a, and is substantially flush with the other side surface 40a of the first flange 40 in the Y-axis direction. It is preferable. This is to achieve both the shielding effect of the laser beam by the shielding piece 73 as described later and the compactness of the apparatus.

  It should be noted that the tip end of the shielding piece 73 in the Y-axis direction may slightly protrude outward in the Y-axis direction from the side surface 40a in the Y-axis direction of the first flange portion 40, or slightly retracted inward in the Y-axis direction. May be. The bent tip of the shielding piece 73 enters the terminal gap recess 48 a of the first flange 40, but does not come into contact with the drum core 20 including the first flange 40.

  As shown in FIG. 5 and FIG. 6, fillet forming pieces 69, 79 are integrated with the attachment pieces 61, 71 of the terminal electrodes 60, 70 respectively at the outer end in the Y-axis direction and in the middle of the X-axis direction. Is formed. The fillet forming pieces 69 and 79 are fitted and contacted with fitting recesses 40a1 formed on both side surfaces 40a in the Y-axis direction of the first flange 40, respectively. Note that the fitting recess 40a1 is not necessarily provided. Moreover, it is preferable that the rising height of the fillet forming pieces 69 and 79 in the Z-axis direction is substantially the same as or lower than the thickness of the first flange 40 in the Z-axis direction.

  Next, the manufacturing method of the coil apparatus 2 shown to FIG. 1A-FIG. 4 is demonstrated. First, the drum core 20 shown in FIG. 5 is formed. The molding method of the drum core 20 is not particularly limited, and compression molding, CIM (ceramic injection molding) molding, MIM (metal injection molding) molding, and the like are conceivable. It is fired after forming into a sintered body.

  Next, the 1st terminal electrode 60 and the 2nd terminal electrode 70 are attached to the winding-axis direction outer side end surface 42 in the 1st collar part 40 of the drum core 20. As shown in FIG. The first terminal electrode 60 and the second terminal electrode 70 can be easily formed by stamping and bending a single metal plate (for example, a copper plate). After the terminal electrodes 60 and 70 are attached to the drum core, or before that, the wire 12 is wound around the core portion 30 of the drum core 20 shown in FIG.

  In a state where the coil portion 10 is formed on the core portion 30, the lead portions 12a and 12b, which are both ends of the wire constituting the coil portion 10, are connected to the grip piece 64 and the first piece 64 of the first terminal electrode 60, as shown in FIG. The gripping piece 74 of the two-terminal electrode 70 is positioned below the Z-axis direction. In this state, next, as shown in FIG. 8, only the temporary fixing pieces 65 and 75 are bent, and the lead portions 12a and 12b are moved between the temporary fixing pieces 65 and 75 and the rising pieces 62 and 72. It is sandwiched and temporarily fixed under the gripping pieces 64 and 74.

  In this state, when the lead portions 12a and 12b shown in FIG. 8 are viewed from the front side in the X-axis direction, the lead portions extending from the temporary fixing pieces 65 and 75 to the outer side in the Y-axis direction are not hidden by the connection pieces 68. Can see.

  In this state, the lead portions 12a and 12b are formed by irradiating the coating portions peeling laser light from the front side in the X-axis direction toward the lead portions 12a and 12b protruding from the temporary fixing pieces 65 and 75. The coating layer such as polyamideimide formed on the outer periphery of the wire can be peeled off.

  Even if the laser beam is irradiated, since the rising pieces 62 and 72 and the shielding pieces 63 and 73 are present, the laser beam is not irradiated to the drum core 20 and the deterioration of the drum core can be prevented. Further, since the lead portions 12a and 12b are irradiated with laser while being temporarily fixed by the temporary fixing pieces 65 and 75, the influence of the peeling of the coating layer of the wire reaches the temporary fixing pieces 65 and 75, which is unnecessary. The release layer is not removed within the range. In addition, when using the wire which does not need to peel a coating layer as the wire 12, the peeling process of the coating layer by such laser irradiation becomes unnecessary.

  Next, as shown in FIG. 9, the connecting pieces 66 and 76 (including the wide portions 68 and 78) are bent, and the leading ends of the lead portions 12a and 12b are sandwiched and temporarily fixed. In this state, the leading ends 12a1 and 12b1 of the lead portions 12a and 12b protrude slightly from the outer ends in the Y-axis direction of the wide portions 68 and 78, and protrude beyond the side surface 40a of the first flange portion 40 in the Y-axis direction. Also good.

  In this state, the laser beam for welding is directed from the front side in the X-axis direction toward the irradiation range LB (for example, a circular irradiation range) including the tips 12a1 and 12b1 of the lead portions 12a and 12b and the wide portions 68 and 78. Irradiate. As a result, as shown in FIG. 1B, at least the tip of the lead portion 12a and the connection piece 66 (including the wide portion 68) are integrated to form the lead connection portion 68a. Similarly, at least the tip of the lead portion 12b and the connecting piece 76 (including the wide portion 78) are integrated to form the lead connecting portion 78a. The outer ends of the lead connecting portions 68a and 78a in the Y-axis direction are substantially flush with the Y-axis direction side surface 40a of the first flange 40, or retracted in the Y-axis direction as a result of laser welding. .

  Even if the laser beam for welding is irradiated, since the rising pieces 62 and 72 and the shielding pieces 63 and 73 are present, the laser beam is not irradiated to the drum core 20 and the deterioration of the drum core can be prevented. In laser welding, as shown in FIG. 9, it is preferable that the wide portions 68 and 78 are located on the front side of the lead portions 12a and 12b when viewed from the direction in which the laser light is emitted.

  With this configuration, the leading ends 12a1 and 12b1 of the lead portions 12a and 12b are first melted and contracted inward in the Y-axis direction by laser light irradiation, and integrated with the wide portions 68 and 78, as shown in FIG. 1B. It is easy to make the lead connection portions 68a and 78a made of a weld ball close to a spherical shape. The outer diameter of the weld ball is not particularly limited, but is preferably 0.35 to 0.45 mm. It is preferable that the lead joint portions 68a and 78a made of weld balls are not integrated with the shielding pieces 63 and 73 and the rising pieces 62 and 72 located behind the X-axis direction. More preferably, the shielding pieces 3 and 73 are held in a space between the lead joint portions 68 a and 78 a made of weld balls and the first flange portion 40 of the core 20. However, they may be in contact with each other.

  In the drawing, only the leading ends of the lead portions 12a and 12b and the wide portions 68 and 78 are integrated to form lead connecting portions 68a and 78a. Depending on the amount of energy of laser irradiation, the tips of the lead portions 12a and 12b and the connecting pieces 66 and 76 may be integrated into the ball-shaped lead connecting portions 68a and 78a. In some cases, the temporary fixing pieces 65 and 75 may be integrated with the ball-shaped lead connecting portions 68a and 78a, respectively.

  In the coil device 2 according to the present embodiment, as shown in FIG. 4, one side surface 40 b in the X-axis direction of the first collar portion 40 faces the rising pieces 62 and 72 of the terminal electrodes 60 and 70. The rising piece facing flat surfaces 45a and 46a for positioning the connecting portion are formed. For this reason, the gripping pieces 64 and 74 which are a part of the connecting portions of the terminal electrodes 60 and 70 are well positioned with respect to the first flange portion 40 of the drum core, and the lead portions 12a and 12a of the wire 12 in the gripping pieces. 12b can be reliably connected to the terminal electrodes 60 and 70 by laser irradiation. Therefore, a strong and reliable wire connection process is possible.

  In the coil device 2 according to the present embodiment, the side surface 40b of the first flange 40 is recessed inward from the rising piece facing flat surfaces 45a and 46a and includes the rising pieces 62 and 72 (including the shielding pieces 63 and 73). ) Terminal gap recesses 47a and 48a are formed together with the rising piece facing flat surfaces 45a and 46a. For this reason, the thermal shock at the time of laser welding the lead portions 12a and 12b of the wire 12 to the connecting portions of the terminal electrodes 60 and 70 is mitigated, and breakage, cracking, chipping and the like of the core 20 can be effectively prevented. . In addition, since there is a gap between the side surface 40b of the first flange 40 and the rising pieces 62 and 72 of the terminal electrode, the external force acting on the terminal electrodes 60 and 70 is absorbed, Breakage of the core 20 can be effectively prevented. Furthermore, since there is a gap between the side surface 40b of the first flange 40 and the rising pieces 62, 72 of the terminal electrode, the heat dissipation of the connecting portion is also excellent.

  In the present embodiment, the rising size 62 of the terminal electrodes 60 and 70 is formed at the corner of the first flange 40 because the outer size of the second flange 50 is larger than the outer size of the first flange 40. , 72 is easy to make the recess 44 (see FIG. 4).

  That is, in this embodiment, it is possible to minimize the protruding amount of the terminal fittings 60 and 70 with respect to the second flange 50 without maintaining the size of the flanges 40 and 50 and reducing the inductance. In addition, there is less possibility that the terminal fittings 60 and 70 and the lead connection portions 68a and 78a collide with the mounting device or the like during the transfer of the coil device.

  In the present embodiment, the grip pieces 64 and 74 are formed with slits 67 and 77. Since the slits 67 and 77 are formed, the heat dissipation is improved. In addition, since the slits 67 and 77 are provided between the temporary fixing pieces 65 and 75 and the connection pieces 66 and 76, the size of the weld ball-shaped lead connection portions 68a and 78a can be easily controlled, which is convenient for connection. Therefore, it is possible to easily form the lead connecting portions 68a and 78a having good sizes.

  Furthermore, in this embodiment, the lead portions 12a and 12b of the winding wire 12 are higher than laser welding (temperature of 1000 ° C. or higher), that is, a temperature (230 to 280 ° C.) for forming a solder fillet. And terminal electrodes 60 and 70 are connected. Therefore, the wire 12 can be securely and reliably connected.

  In the coil device 2 of the present embodiment, the rising pieces 62 and 72 are formed only at one end in the X-axis direction of the mounting pieces 61 and 71, and the rising piece is formed at the other end. Not formed. For this reason, it is possible to effectively prevent displacement of the terminal electrodes 60 and 70 along the X-axis direction as compared with the prior art.

  Incidentally, conventionally, a rising piece is also formed at the other end, and a solder fillet is formed at that portion. And the solder fillet is not formed in the upright pieces 62 and 72 because of the connecting portions 68a and 78a by laser welding. Therefore, conventionally, the entire coil device 2 together with the terminal electrodes 60 and 70 is arranged in the X-axis direction with respect to the circuit board due to the external force due to the solder fillet attached to the rising piece formed at the other end. There was a risk of displacement.

  On the other hand, in this embodiment, the rising piece is not formed at the other end in the X-axis direction of the attachment pieces 61 and 71. Instead, from one end in the short direction (Y-axis direction) intersecting with the longitudinal direction (X-axis direction) of the mounting pieces 61 and 71, the first flange portion 40 stands integrally along the Y-axis direction side surface 40a. Solder fillets at the time of mounting are formed on the raised fillet forming pieces 69 and 79. By this solder fillet, the mounting circuit board (not shown) and the terminal electrodes 60, 70 are firmly connected, and the positional displacement of the terminal electrodes 60, 70 along the X-axis direction can be effectively prevented. .

  Further, by providing these fillet forming pieces 69 and 79 on the terminal electrodes 60 and 70, the following effects can be expected. That is, when the coil device 2 is mounted on, for example, a circuit board, the solder attached to the lower surfaces of the terminals 60 and 70 also adheres to the outer surfaces of the fillet forming pieces 69 and 79, When viewed from the above, it is possible to check the degree of soldering without being hidden by the second flange 50.

  In addition, since a pair of terminal electrodes 60 and 70 are attached to the winding direction outer side end face 42 of the first flange portion 40, the positional deviation in the Y direction of the terminal electrodes is formed in the pair of terminal electrodes 60 and 70, respectively. This is prevented by the interaction of the opposing joining forces of the solder fillets formed on the fillet forming pieces 69, 79.

  In the present embodiment, lead connection portions 68 a and 78 a in which the lead portions 12 a and 12 b of the wire 12 are connected to the connection pieces 66 and 76 are formed within the thickness range of the first flange portion 40. By adopting such a configuration, the coil device 2 can be made compact.

  Furthermore, in the present embodiment, the rising height of the fillet forming pieces 69 and 79 is lower than the thickness of the first flange portion 40 in the winding axis direction. With this configuration, the coil device 2 can be made compact. Further, the possibility that the exterior resin 15 adheres to the fillet forming pieces 69 and 79 is reduced, and does not hinder the formation of the solder fillet during mounting.

  Moreover, in this embodiment, the fitting recessed part 40a1 in which the fillet formation pieces 69 and 79 enter is formed in the Y-axis direction side surface 40a of the 1st collar part 40. As shown in FIG. By fitting the fillet forming pieces 69 and 798 in the fitting recess 40a1, the positioning of the terminal electrodes 60 and 70 and the core 20 is facilitated. Further, the possibility that the exterior resin 15 adheres to the fillet forming pieces 69 and 79 is reduced, and does not hinder the formation of the solder fillet during mounting.

  The outer surfaces of the fillet forming pieces 69 and 79 are flush with the Y-axis direction side surface 40a other than the fitting recess 40a1, or are recessed inside the Y-axis direction side surface 40a other than the fitting recess 40a1. With this configuration, the handling characteristics of the coil device 2 before mounting are improved. That is, the edge portions of the fillet forming pieces 69 and 79 are not caught by other parts and devices, and the other parts and devices are not damaged.

  As shown in FIG. 9, in order to connect the tips 12a1 and 12b1 of the lead portions 12a and 12b of the wire 12 and the wide portions 68 and 78 of the connection pieces 66 and 76, the laser beam LB is irradiated from the X-axis direction. . Shielding pieces 63 and 73 are arranged behind the tips 12a1 and 12b1 of the lead portions 12a and 12b and the wide portions 68 and 78 of the connection pieces 66 and 76, respectively. Therefore, the shielding pieces 63 and 73 are shielded from the laser beam LB.

  Therefore, even if the device is made compact and the connecting piece 66 is arranged near the core 20, there is no possibility that the core 20 will be damaged by the laser beam or its reflection during laser welding. Therefore, the core 20 is not damaged, cracked or chipped by thermal shock.

  Further, since the shielding pieces 63 and 73 are held in the space between the lead joint portions 68a and 78a and the first flange portion 40 of the core 20, the thermal influence of the laser beam when the welding ball is made. Can hardly be transmitted to the core 20, and damage to the core 20 can be further reduced.

  Furthermore, since the shielding pieces 63 and 73 are formed integrally with the terminal electrodes 60 and 70, respectively, it is not necessary to prepare a shielding member separately, which contributes to a reduction in the number of parts.

  The present invention is not limited to the above-described embodiment, and can be variously modified within the scope of the present invention.

  For example, the shielding member of the present invention may be made of ceramic, metal, or the like, and may be attached only to a necessary portion of the core 20 or may be integrally formed.

  In the above-described embodiment, as shown in FIGS. 5 and 7, the temporary fixing pieces 65 and 75 and the connection pieces 68 and 78 are opened before the laser welding, and thereafter, as shown in FIG. 8, The temporary fixing pieces 65 and 75 are bent, and then the connecting pieces 68 and 78 are bent. However, as shown in FIG. 6, the temporary fixing pieces 65 and 75 and the connecting pieces 68 and 78 may be bent from the beginning.

  That is, at least the temporary fixing pieces 65 and 75 may be bent in advance on the upper convex in the Z-axis direction so as to accommodate the lead portions 12a and 12b of the wire 12 from the lower side in the Z-axis direction. The same applies to the connection pieces 68 and 78.

  Further, in the terminal electrodes 60 and 70 of the above-described embodiments, it is preferable that the surface in contact with the drum core 20 is not formed with a plating film in order to improve the adhesion to the drum core. In order to improve the bonding property with the solder, tin plating may be performed on the back surface to be the surface.

DESCRIPTION OF SYMBOLS 2 ... Coil apparatus 10 ... Coil part 12 ... Wire 15 ... Exterior resin 20 ... Drum core 30 ... Core part 40 ... 1st collar part 40a, 40b ... Side 42 ... Winding direction outer side end surface 43 ... Winding direction inner surface 44 ... Cutting Notches 45a, 46a ... Standing piece opposing planes 47a, 48a ... Terminal gap recesses 45b, 46b ... Opposite side planes 47b, 48b ... Opposite side recess 50 ... Second flange 52 ... Second axial outer end face 53 ... Second Axial inner surface 54 ... R portion 60 ... first terminal electrodes 61, 71 ... mounting pieces 62, 72 ... connecting upright pieces 63, 73 ... shielding pieces 64, 74 ... gripping pieces 65, 75 ... temporary fastening pieces 66, 76 ... Connection pieces 67, 77 ... Slits 68, 78 ... Wide portions 68a, 78a ... Lead connection portions 69, 79 ... Fillet forming pieces

Claims (8)

A magnetic core having a core portion around which a wire is wound so as to form a coil;
A coil device having a terminal electrode attached to an outer end surface in the winding axis direction of the collar portion formed at an end portion in the winding axis direction of the core portion,
The terminal electrode is
A mounting piece in contact with the outer end surface in the winding axis direction of the flange,
From one end in the longitudinal direction of the attachment piece, a rising piece for connection that is integrally raised along the first axial direction side surface of the flange,
A connection piece formed integrally with the upper end side of the connection rising piece, and formed with a weld ball to which the lead portion of the wire is connected by laser welding,
A coil device in which a laser shielding member is disposed between the weld ball and the magnetic core.   The coil device according to claim 1, wherein the shielding member is held in a space between the weld ball and the magnetic core.   The coil device according to claim 2, wherein the shielding member is formed integrally with the terminal electrode.   The coil device according to any one of claims 1 to 3, wherein a lead connection portion made of the weld ball is formed within a thickness range of the flange portion.   The coil device according to any one of claims 1 to 4, wherein a periphery of a core portion around which the wire is wound is covered with an exterior resin.   The temporary fixing piece for temporarily fixing the lead portion of the wire is integrally formed on the upper end side of the rising piece for connection, separately from the connection piece. The coil apparatus as described.   On the side surface in the first axial direction of the flange portion, the rising piece facing plane that positions the connecting piece so as to oppose the connecting rising piece, and the recess is formed inwardly from the rising piece facing plane. The coil device according to any one of claims 1 to 6, wherein a terminal gap recess for forming a gap with the rising piece is formed.   In order to connect the tip of the lead portion of the wire and the connecting piece, laser light is emitted from the direction intersecting the first axial side surface toward the tip of the connecting piece and the lead portion of the wire. The said shielding member which shields that the said laser beam is irradiated to the said magnetic core when irradiated is integrally formed in the said starting piece for connection. Coil device.

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