JP2007208227A - Common mode choke coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a common mode choke coil with stable characteristics by preventing a reduction in coupling coefficient due to the slack of a winding. <P>SOLUTION: In a region where at least the terminal part of a winding part of a winding core part 3 of a ferrite core 2 is located, there are provided engagement parts 7a and 7b. By hooking windings A and B on the engagement parts 7a and 7b, the slack of the windings due to the stretch of a conductor at the time of conductor junction is suppressed, and the generation of a gap between a pair of conductors in one turn of winding start or winding end is prevented. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention belongs to the technical field of a wound chip type common mode choke coil used in various electronic devices.

  The common mode choke coil is a coil component used for filtering radiation noise and the like of various electronic devices typified by personal computers, and the common of each line current flowing through a plurality of (2-4) coils with high coupling. This is one of the coil components that cancel and remove mode (in-phase component) noise.

  As shown in FIGS. 17 to 20, as a conventional structure of a wound chip type common mode choke coil, flange portions 44 are respectively provided at both ends in the axial direction AX of a core portion 43 of a ferrite core 42 made of a ferrite material or the like. A plurality of legs 45a, 45b, 45c, and 45d are provided on the lower surface of the flange 44, and terminal electrodes 46a, 46b, 46c, and 46d are formed at the tips of the legs, respectively. A winding portion M in which a plurality of windings A and B are wound around the portion 43 is formed, and lead-out portions A11, A12, B11, and B12 extend from the ends of the winding portion M, respectively, There is a common mode choke coil 41 having a structure in which the terminal electrodes 46a, 46c, 46b, and 46d are connected to each other through the joints A1, A2, B1, and B2 and are electrically connected by thermocompression bonding. .

  Also, in [Patent Document 1] below, the end of the winding is in contact with the terminal electrode by providing cut grooves at both ends of the core at the inner base of the flange where the terminal electrode is formed. A common mode choke coil having high reliability that prevents short circuit is shown.

JP 2002-313646 A

  When the end of the conducting wire is thermocompression bonded, the conducting wire is stretched because the wire is crushed and crimped. Since the conducting wire extends so as to spread in all directions, the lead-out portion also extends, and the winding may loosen. When winding is performed with a ferrite core having a conventional structure as shown in FIG. 20, as shown in FIG. 21, the winding is displaced and a gap 47 is formed between a pair of conducting wires at the start or end of winding. It sometimes occurred. For this reason, there has been a problem that the coupling coefficient is lowered and the normal mode impedance is increased.

  The present invention improves the winding structure of the common code choke coil as described above, and prevents a decrease in the coupling coefficient and provides a structure in which a wound common mode choke coil with more stable characteristics can be obtained. It is to provide.

  According to the present invention, flanges are provided at both axial ends of the core portion of the ferrite core, a plurality of legs are provided on the lower surface of the flange, terminal electrodes are respectively formed on the plurality of legs, and the winding In the common mode choke coil in which a winding part in which a plurality of windings are wound around the core part is formed, and a lead part extends from the end part of the winding part and is conductively connected to the terminal electrode. The ferrite core proposes a common mode choke coil including a locking portion at least in a region where an end of the winding portion of the winding core portion is located.

  Further, the present invention proposes a common mode choke coil characterized in that the locking portion is a groove.

  In addition, the present invention proposes a common mode choke coil, wherein the locking portion is a protrusion.

  According to the structure of the present invention, it is possible to prevent a gap from being generated in the pair of conductors by hooking the winding on the engaging portion formed in the ferrite core. As a result, a decrease in coupling coefficient can be prevented, and a common mode choke coil having stable characteristics can be obtained.

  An embodiment of a common mode choke coil according to the present invention will be described with reference to the following drawings.

  FIG. 1 is a bottom view showing the common mode choke coil of the first embodiment. FIG. 2 is a top view showing the common mode choke coil of the first embodiment. FIG. 3 is a side view showing the common mode choke coil of the first embodiment. FIG. 4A is a bottom view showing the ferrite core of the common mode choke coil of the first embodiment. FIG. 4B is a side view of the same. FIG. 4C is a front view of the same. FIG. 5 is a bottom view showing the common mode choke coil of the second embodiment. FIG. 6 is a top view showing the common mode choke coil of the second embodiment. FIG. 7 is a side view showing the common mode choke coil of the second embodiment. FIG. 8A is a bottom view showing the ferrite core of the common mode choke coil according to the second embodiment. FIG. 8B is a side view of the same. FIG. 8C is a cross-sectional view taken along line X-X ′. FIG. 9 is a bottom view showing the common mode choke coil of the third embodiment. FIG. 10 is a top view showing the common mode choke coil of the third embodiment. FIG. 11 is a side view showing the common mode choke coil of the third embodiment. FIG. 12A is a bottom view showing the ferrite core of the common mode choke coil according to the third embodiment. FIG. 12B is a side view of the same. FIG. 12C is a cross-sectional view taken along the line Y-Y ′. FIG. 13 is a bottom view showing the common mode choke coil of the fourth embodiment. FIG. 14 is a top view showing a common mode choke coil according to the fourth embodiment. FIG. 15 is a side view showing a common mode choke coil according to the fourth embodiment. FIG. 16A is a bottom view showing the ferrite core of the common mode choke coil according to the fourth embodiment. FIG. 16B is a side view thereof. FIG. 16C is a cross-sectional view of Z-Z ′.

  As shown in FIGS. 1 to 4, in the common mode choke coil 1 according to the first embodiment of the present invention, the winding portion 3 as shown in FIGS. 4A, 4 </ b> B, and 4 </ b> C is used. The flange portions 4 are provided at both ends in the axial direction AX, and the leg portions 5a, 5b, 5c, and 5d are provided on the lower surface of the flange portion 4, and the ridge formed by the upper surface and the side surface of the winding portion 3 is provided. A ferrite core 2 is prepared in which groove-like locking portions 7a and 7b are formed in a point-symmetrical position around a vertical central axis in a side region near the flange portion including the leg portion as shown in FIG. Terminal electrodes 6a, 6b, 6c and 6d are provided on 5a, 5b, 5c and 5d, respectively, and terminal junctions A1, B1, A2 and B2 of a plurality of windings A and B (two in this embodiment) are provided. Each of the terminal electrodes 6a, 6b, 6c, 6d is conductively connected by thermocompression bonding or the like, and ends A3, B3 of the winding portions. A4, and B4 and the terminal joint portions A1, B1, A2, B2 and between the are connected by respective lead portions A11, B11, A12, B12.

  In the present embodiment, as shown in FIGS. 2 and 3, end portions A3, B3 and A4, B4 of the winding portion are hooked on the locking portions 7a and 7b. In this way, when the winding is crimped to the terminal electrode, even if the winding is extended and loosened, the movement of the winding is suppressed by the locking portions 7a and 7b, so that the generation of the gap 47 as shown in FIG. 21 is prevented. can do. This can prevent the coupling coefficient from decreasing.

  In the common mode choke coil 11 of the second embodiment according to the present invention shown in FIGS. 5 to 8, the shaft of the winding part 13 as shown in FIGS. 8 (a), (b) and (c). The flanges 14 are provided at both ends in the direction AX, the leg portions 15a, 15b, 15c, and 15d are provided on the lower surface of the flange portion 14, and the ridge portion formed by the upper surface and the side surface of the winding portion 13 is provided. A ferrite core 12 having groove-shaped locking portions 17a and 17b formed in a point-symmetrical position around the vertical central axis in a side region near the flange portion is prepared, and as shown in FIG. Terminal electrodes 16a, 16b, 16c, and 16d are provided on 15b, 15c, and 15d, respectively, and terminal junctions A1, B1, A2, and B2 of a plurality of (two in this embodiment) windings A and B are terminals. By thermocompression bonding to the electrodes 16a, 16b, 16c, 16d Are conductively connected, it is connected end A3 of the winding portion, B3, A4, B4 and the terminal joint portions A1, B1, A2, B2 and between the respectively lead portions A11, B11, A12, B12.

  In the present embodiment, the locking portions 17a and 17b are grooves formed only in the ridge portion formed on the upper surface and the side surface of the winding portion. The locking portions 17a and 17b can exert their effects as long as they can press the ends A3, B3, A4, and B4 of the winding portion. Therefore, according to the present embodiment, the generation of the gap 47 as shown in FIG. 21 can be prevented, and the reduction of the coupling coefficient can be prevented.

  In the common mode choke coil 21 according to the third embodiment of the present invention shown in FIGS. 9 to 12, the shaft of the winding portion 23 as shown in FIGS. 12 (a), 12 (b), and 12 (c). The flange portions 24 are provided at both ends in the direction AX, and leg portions 25a, 25b, 25c, and 25d are provided on the lower surface of the flange portion 24, and include ridge portions formed by the upper surface and the side surface of the winding portion 23. A ferrite core 22 is prepared in a side surface region near the flange portion so that protrusion-like locking portions 27a and 27b extending from the upper surface to the bottom surface are in a point-symmetrical position around the vertical center axis, as shown in FIG. As described above, terminal electrodes 26a, 26b, 26c, and 26d are provided on the legs 25a, 25b, 25c, and 25d, respectively, and a plurality of (in this embodiment, two) windings A and B are connected to terminal joints A1, B1, A2, and B2 are terminal electrodes 26a, 6b, 26c, and 26d are conductively connected by thermocompression bonding or the like, and between the end portions A3, B3, A4, and B4 of the winding portion and the terminal joint portions A1, B1, A2, and B2 are drawn portions A11 and B11, respectively. , A12 and B12.

  In the present embodiment, the locking portions 27a and 27b are protrusions formed on the side surfaces and extending from the top surface to the bottom surface. The end portions A3, B3, A4, and B4 of the winding portion can be pressed by the protruding locking portions 27a and 27b. With such a configuration, the generation of the gap 47 as shown in FIG. 21 can be prevented, so that the coupling coefficient can be prevented from being lowered.

  In the common mode choke coil 31 of the fourth embodiment according to the present invention shown in FIGS. 13 to 16, the shaft of the winding portion 33 as shown in FIGS. 16 (a), (b), and (c). The flanges 34 are provided at both ends in the direction AX, and the legs 35 a, 35 b, 35 c, 35 d are provided on the lower surface of the flange 34, and include ridges formed by the upper surface and side surfaces of the winding portion 33. A ferrite core 32 is prepared in which protrusion-like locking portions 37a and 37b are formed in a point-symmetrical position around the vertical center axis in the upper surface region near the flange portion, and as shown in FIG. , 35b, 35c, and 35d are provided with terminal electrodes 36a, 36b, 36c, and 36d, respectively, and terminal junctions A1, B1, A2, and B2 of a plurality (two in this embodiment) of windings A and B are respectively provided. Terminal electrodes 36a, 36b, 36c, 36d Conductive connection is made by thermocompression bonding or the like, and between the end portions A3, B3, A4, B4 of the winding portion and the end portions A1, B1, A2, B2 of the windings A, B, respectively, lead portions A11, B11, They are connected by A12 and B12.

  In the present embodiment, the locking portions 37 a and 37 b are protrusions formed only on the ridge portion formed on the surface of the winding portion 33. Even in the projection-like locking portions 37a and 37b as in the present embodiment, the end portions A3, B3, A4, and B4 of the winding portion can be pressed. With such a configuration, the generation of the gap 47 as shown in FIG. 21 can be prevented, so that the coupling coefficient can be prevented from being lowered.

  The common mode choke coils 1, 11, 21, and 31 having the core structure and the winding structure according to the present invention as described above can obtain high characteristics with high coupling, high reliability, and high speed differential transmission. It is particularly effective.

  As a precaution, the common mode choke coil of the present invention has a resin mold type in which the outer periphery of the coil is covered with a resin material or a ferrite plate-like magnetic core attached to the upper surface of the ferrite core with an adhesive or the like. Of course, a common mode choke coil having a closed magnetic circuit structure is also included.

It is a bottom view which shows the common mode choke coil of 1st embodiment. It is a top view which shows the common mode choke coil of 1st embodiment. It is a side view which shows the common mode choke coil of 1st embodiment. (A) shows the bottom view of the ferrite core of the common mode choke coil of the first embodiment. (B) shows the side view. (C) shows a sectional view of W-W '. It is a bottom view which shows the common mode choke coil of 2nd embodiment. It is a top view which shows the common mode choke coil of 2nd embodiment. It is a side view which shows the common mode choke coil of 2nd embodiment. (A) shows the bottom view of the ferrite core of the common mode choke coil of the second embodiment. (B) shows the side view. (C) shows a cross-sectional view of X-X ′. It is a bottom view which shows the common mode choke coil of 3rd embodiment. It is a top view which shows the common mode choke coil of 3rd embodiment. It is a side view which shows the common mode choke coil of 3rd embodiment. (A) shows the bottom view of the ferrite core of the common mode choke coil of the third embodiment. (B) shows the side view. (C) shows a cross-sectional view of Y-Y ′. It is a bottom view which shows the common mode choke coil of 4th embodiment. It is a top view which shows the common mode choke coil of 4th embodiment. It is a side view which shows the common mode choke coil of 4th embodiment. (A) shows the bottom view of the ferrite core of the common mode choke coil of the fourth embodiment. (B) shows the side view. (C) shows a sectional view of Z-Z ′. It is a bottom view which shows the conventional common mode choke coil. It is a top view which shows the conventional common mode choke coil. It is a side view which shows the conventional common mode choke coil. (A) shows the bottom view of the ferrite core of the conventional common mode choke coil. (B) shows the side view. (C) shows the same front view. It is a top view which shows the problem of the conventional common mode choke coil.

Explanation of symbols

1, 11, 21, 31, 41 Common mode choke coil 2, 12, 22, 32, 42 Ferrite core 3, 13, 23, 33, 43 Winding part 4, 14, 24, 34, 44 Fence part 5a, 5b 5c, 5d, 15a, 15b, 15c, 15d, 25a, 25b, 25c, 25d, 35a, 35b, 35c, 35d, 45a, 45b, 45c, 45d Legs 6a, 6b, 6c, 6d, 16a, 16b, 16c, 16d, 26a, 26b, 26c, 26d, 36a, 36b, 36c, 36d, 46a, 46b, 46c, 46d Terminal electrode 7a, 7b, 17a, 17b Locking part (groove)
27a, 27b, 37a, 37b Locking part (protrusion)
47 Gap A, B Windings A1, A2, B1, B2 Terminal joints A3, A4, B3, B4 Ends A11, A12, B11, B12 of the winding part.
AX Axial direction M Winding part

Claims (3)

A flange portion is provided at both axial ends of the core portion of the ferrite core, a plurality of leg portions are provided on the lower surface of the flange portion, terminal electrodes are respectively formed on the plurality of leg portions, and a plurality of portions are provided on the core portion. In a common mode choke coil in which a winding portion is formed by winding a plurality of windings, and a lead portion extends from an end portion of the winding portion and is electrically connected to the terminal electrode,
The ferrite core includes a locking portion at least in a region where an end portion of the winding portion of the winding core portion is located.   The common mode choke coil according to claim 1, wherein the locking portion is a groove.   The common mode choke coil according to claim 1, wherein the locking portion is a protrusion.

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