Source: http://www.google.com/patents/US7471179?dq=7125605
Timestamp: 2014-04-16 16:23:02
Document Index: 597151353

Matched Legal Cases: ['art 12', 'art 12', 'art 12', 'art 12', 'art 12', 'art 14', 'art 14', 'art 12', 'art 14', 'art 12', 'art 12', 'art 15', 'art 14', 'art 15', 'art 15', 'art 12', 'art 14', 'art 15', 'art 15', 'art 14', 'art 16', 'art 14', 'art 16', 'art 16', 'art 12', 'art 14', 'art 16', 'art 16', 'art 14', 'art 15', 'art 15', 'art 15', 'art 12', 'art 15', 'art 15', 'art 15', 'art 15', 'art 16', 'art 16', 'art 16', 'art 12', 'art 16', 'art 16', 'art 16', 'art 16', 'art 16', 'art 16', 'art 16']

Patent US7471179 - Coil component - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsEach terminal electrode has a welded portion at which each end portion of a conducting wire is electrically connected to each terminal electrode upon laser welding. The conducting wire is provided with an insulation coating. The insulation layer has an edge on the surface of the conducting wire. Each...http://www.google.com/patents/US7471179?utm_source=gb-gplus-sharePatent US7471179 - Coil componentAdvanced Patent SearchPublication numberUS7471179 B2Publication typeGrantApplication numberUS 11/812,058Publication dateDec 30, 2008Filing dateJun 14, 2007Priority dateJun 30, 2006Fee statusPaidAlso published asDE102007030057A1, US20080003865Publication number11812058, 812058, US 7471179 B2, US 7471179B2, US-B2-7471179, US7471179 B2, US7471179B2InventorsYutaka Hatakeyama, Kouzou KajiwaraOriginal AssigneeTdk CorporationExport CitationBiBTeX, EndNote, RefManPatent Citations (15), Non-Patent Citations (1), Classifications (7), Legal Events (2) External Links: USPTO, USPTO Assignment, EspacenetCoil componentUS 7471179 B2Abstract Each terminal electrode has a welded portion at which each end portion of a conducting wire is electrically connected to each terminal electrode upon laser welding. The conducting wire is provided with an insulation coating. The insulation layer has an edge on the surface of the conducting wire. Each welded portion has a bulge portion bulging in a direction away from the core and in contact with only the edge of the insulation coating. The edge determines a shape position and size of a melted bulge portion.
at least one conducting wire provided with an insulation coating having a distal edge;
a core on which the at least one conducting wire is wound, the core having mounting portions to be mounted on a circuit board; and
terminal electrodes provided at the mounting portions and having numbers corresponds to the numbers of end portions of the at least one conducting wire, each terminal electrode having a welded portion at which each of the end portions of the at least one conducting wire is electrically connected to each of the terminal electrodes upon welding, each welded portion having a bulge portion bulging in a direction away from the core and in contact with only the distal edge of the insulation coating.
2. The coil component as defined in claim 1, wherein the insulation covering is made from a material providing a heat resistance capable of avoiding melting at a temperature required for electrically connecting the end portion to the terminal electrode by a laser welding.
3. The coil component as defined in claim 1, wherein each terminal electrode comprises a terminal bracket each including a holding portion that temporarily holds each end portion at a position close to the welding portion, each end portion having a region from the holding portion to the bulge portion, the region being entirely covered with the insulation coating.
4. The coil component as defined in claim 1, wherein each of the terminal electrodes has a foundation portion facing each end portion, the bulge portion facing the foundation, and
the coil component further comprising an insulating layer provided in the bulge portion at a position between an equivalent end portion corresponding to the end portion and the foundation portion.
5. The coil component as defined in claim 4, wherein the insulating layer is a part of the insulation coating.
6. The coil component as defined in claim 4, wherein each of the terminal electrode is in a form of a terminal bracket, a part of the terminal bracket and the end portion of the conducting wire forming the equivalent end portion in the bulge portion as a result of melting thereof upon laser welding. Description
CROSS-REFERENCE TO THE RELATED APPLICATION The present application is closely related to a U.S. Patent Application filed on the even date (Priority application No. JP2006-181881 filed Jun. 30, 2006).
BACKGROUND OF THE INVENTION The present invention relates to a coil component, and more particularly to a type thereof including terminal electrodes and a conducting wire, in which each end of the conducting wire is electrically connected to respective terminal electrode.
A coil component such as a common mode filter has been known in which a plurality of insulated conducting wires are wound over a drum type core. Japanese Patent Application Publication No. 2004-14671 discloses the drum type core including a core part and a pair of flange parts each coupled to each axial end of the core part. The plurality of conducting wires, for example, two wires, are each wound over the core part of the drum type core.
A plurality of terminal electrodes, whose number corresponds to the numbers of conducting wires, are provided at each flange part. One end portion of each conducting wire is electrically connected to each terminal electrode of each flange part. The other end of each conducting wire is electrically connected to each terminal electrode of the other flange part. For the connection, the insulation coating at each end portion of each conducting wire has been peeled off.
Each terminal electrode is constituted by a metallic terminal bracket. A portion of the terminal electrode to which each end of each conducting wires is connected will be referred to as a connection part.
Each terminal electrode has a temporary wire holding part at a position close to the connection part for holding the end portion of the conducting wire to facilitate electrical connection by for example welding. The insulated layer is made from urethane, for example. However, in the conventional coil component, more improved electrical connection is required at the connection part.
SUMMARY Accordingly, it is an object of the present invention to provide a coil component having an improved connection part ensuring satisfactory electrical connection between the terminal electrode and the end portion of the conducting wire.
This and other objects of the present invention will be attained by a coil component including at least one conducting wire, a core, and terminal electrodes. The at least one conducting wire is provided with an insulation coating having a distal edge. The at least one conducting wire is wound over the core. The core has mounting portions to be mounted on a circuit board. The terminal electrodes are provided at the mounting portions and have numbers corresponds to the numbers of end portions of the at least one conducting wire. Each terminal electrode has a welded portion at which each of the end portions of the at least one conducting wire is electrically connected to each of the terminal electrodes upon welding. Each welded portion has a bulge portion bulging in a direction away from the core and in contact with only the distal edge of the insulation coating.
DETAILED DESCRIPTION A coil component according to an embodiment of the present invention will be described with reference to FIG. 1 through FIG. 5. The embodiment pertains to a common mode filter.
The core part 12 and the flanges 13 are formed integrally. A combination of the core part 12 and two flanges 13 is H-shaped in cross-section taken along a plane extending on an axis of the core part 12. The two flanges 13 have shape generally identical to each other. Therefore, a description is hereinafter given for only one of the flanges unless otherwise specified. By definition, a longitudinal direction of the core part 12 will be referred to as �X-axis direction�, a widthwise direction of the core part 12 will be referred to as �Y-axis direction�, and the direction orthogonal to the X-axis and Y-axis directions will be referred to as �Z-axis direction�, as shown in FIG. 1.
In the first part 14, Z-axis direction is a longitudinal direction, and Y-axis direction is a widthwise direction. The first part 14 is a generally rectangular column having a width almost equal to that of the core part 12. The first part 14 includes a pair of first sides 14 a and 14 b, a pair of second sides 14 c and 14 d, and a pair of third sides 14 e and 14 f. The first sides 14 a and 14 b face each other as viewed in the X-axis direction. The second sides 14 c and 14 d face each other as viewed in the Z-axis direction, extending in the direction to cross the first sides 14 a and 14 b (the orthogonal direction in the embodiment). The third sides 14 e and 14 f face each other as viewed in the Y-axis direction, extending in the direction where the third sides 14 e and 14 f cross the first sides 14 a and 14 b and the second sides 14 c and 14 d (the orthogonal direction in the embodiment), respectively. The first sides 14 a and 14 b are each orthogonal to the axial direction of the core part 12. The core part 12 is coupled to the first side 14 b. The second part 15 protrudes from the third side 14 e of the first part 14 in the Y-axis direction. The second part 15 has a generally rectangular column shape having its longitudinal direction in the Z-axis direction. The second part 15 includes a pair of first sides 15 a and 15 b, a pair of second sides 15 c and 15 d, and a third side 15 e. The first sides 15 a and 15 b face each other as viewed in the X-axis direction. The second sides 15 c and 15 d face each other as viewed in the Z-axis direction, extending in the direction to cross the first sides 15 a and 15 b. The third side 15 e extends in the direction to cross the first side 15 a and 15 b, and the second sides 15 c and 15 d. The first sides 15 a and 15 b are each orthogonal to the axial direction of the core part 12. A step is formed between the second side 14 c of the first part 14 and the second side 15 c of the second part 15 across the third side 14 e so that the second side 15 c of the second part 15 is positioned lower than the second side 14 c of the first part 14.
The third part 16 protrudes from the third side 14 f of the first part 14 in the Y-axis direction. The third part 16 is a generally rectangular column having its longitudinal direction in the Z-axis direction. The third part 16 includes a pair of first sides 16 a and 16 b, a pair of second sides 16 c and 16 d, and a third side 16 e. The first sides 16 a and 16 b face each other as viewed in the X-axis direction. The second sides 16 c and 16 d face each other as viewed in the Z-axis direction, extending in the direction to cross the first sides 16 a and 16 b. The third side 16 e extends in the direction to cross the first sides 16 a and 16 b, and the second sides 16 c and 16 d. The first sides 16 a and 16 b are each orthogonal to the axial direction of the core part 12. A step is formed between the second side 14 c of the first part 14 and the second side 16 c of the third part 16 across the third side 14 f so that the second side 16 c of the third part 16 is positioned lower than the second side 14 c of the first part 14.
Each of the first terminal electrodes 41 and 42 includes a first terminal 43, a pair of second terminals 44 and 45 extending from each end of the first terminal 43, and first/second pieces 46 and 47 extending from the second terminal 44. The first terminal 43, the pair of second terminals 44 and 45, and the first piece 46 and a second piece 47 are formed by bending a metal plate. The first terminal 43 faces the first side 15 a of the second part 15 of the flange 13. The second terminal 44 faces the second side 15 c of the second part 15 of the flange 13. The second terminal 45 faces the second side 15 d of the second part 15 of the flange 13. Each end of the pair of second terminals 44 and 45 is bent toward the core part 12.
The second piece 47 serves as a fixing element converted into a molten state upon laser welding. The second piece 47 is bent so as to hold the end portion of the conducting wire 31 with the second terminal 44 (The second piece 47 referred herein is identical to a second piece 57 in FIGS. 2 and 3). In a state that the first piece 46 and the second piece 47 hold the end portion of the conducting wire 31 with the second terminal 44, laser welding is performed as will be described later. The first terminal electrode 41 is thus connected to the end portion of the conducting wire 31 mechanically and electrically. Prior to fitting the first terminal electrodes 41 and 42 to the flange 13, the first terminal 43 in the Z-axis direction is slightly longer than the first side 15 a in the Z-axis direction, and the distance between free ends of the pair of second terminals 44 and 45 in the Z-axis direction is slightly shorter than the first side 15 a in the Z-axis direction.
The first terminal electrodes 41 and 42 are fixed to the second part 15 of the flange 13 by the pair of second terminals 44 and 45 holding the pair of second sides 15 c and 15 d. In order to fit each of the first terminal electrodes 41 and 42 to the second part 15 of the flange 13, the first terminal electrodes 41 and 42 cover the second part 15 from the side of the first side 15 a of the second part 15, while a distance between the pair of second terminals 44 and 45 is increasing.
Each of the second terminal electrodes 51 and 52 includes a first terminal 53, a pair of second terminals 54 and 55 extending from each end of the first terminal 53, and first and second pieces 56 and 57 extending from the second terminal 54. The first terminal 53, the pair of second terminals 54 and 55, and the first and second pieces 56 and 57 are formed by bending a metal plate (see FIGS. 2 and 3). The first terminal 53 faces the first side 16 a of the third part 16 of the flange 13. The second terminal 54 faces the second side 16 c of the third part 16 of the flange 13. The second terminal 55 faces the second side 16 d of the third part 16 of the flange 13. Each end of the pair of second terminals 54 and 55 is bent toward the core part 12.
The second piece 57 serves as a fixing element converted into a molten state upon laser welding. The second piece 57 is bent from the state shown in FIG. 2 so as to hold the conducting wire 31 with the second terminal 54 as shown in FIG. 3. In a state that the first and second pieces 56 and 57 hold the end portion of the conducting wire 31 with the second terminal 54, laser welding is performed. The second terminal electrode 51 is thus connected to the end portion of the conducting wire 31 mechanically and electrically. Prior to fitting the second terminal electrodes 51 and 52 to the flange 13, the first terminal 53 in the Z-axis direction is slightly longer than the first side 16 a in the Z-axis direction, and the distance between free ends of the pair of second terminals 54 and 55 in the Z-axis direction is slightly shorter than the first side 16 a in the Z-axis direction.
The second terminal electrodes 51 and 52 are fixed to the third part 16 of the flange 13 by the pair of second terminals 54 and 55 holding the pair of second sides 16 c and 16 d. In order to fit each of the second terminal electrodes 51 and 52 to the third part 16 of the flange 13, the second terminal electrodes 51 and 52 cover the third part 16 from the side of the first side 16 a of the third part 16, while a distance between the pair of second terminals 54 and 55 is increasing.
As mentioned above, the second piece 57 is melted by laser welding. Further, the end portion of the conducting wire 31 held by the second piece 57 and the second terminal 54 is also melted. Furthermore, a surface area of the second terminal 54, the surface area being facing the second piece 57 and the end portion of the conducting wire 31, is also melted by laser welding. On the other hand, a portion directly facing the second side 16 c of the third part 16 of the flange 13, i.e., a lower portion of second terminal 54 in its thickness direction shown in FIG. 5 remains non-melted as a foundation 54A.
The above parts are thus melted to be mixed with one another, thereby forming a melted portion 16A. As shown in FIG. 5, the melted portion 16A includes a bulge 16B which bulges in a direction away from the second side 16 c of third part 16. In this case, the �bulge 16B� corresponds to a substantially upper portion of the so-called welding ball, except its lower end, which bulges generally hemispherically in a direction away from the third part 16. The bulge 16B does not include the portion which faces the foundation 54A and the insulation covering.
A plate core (not shown) can be placed above the common mode filter 1 so as to make a closed magnetic circuit. To this effect, the plate core will be fixed to the second sides 14 c and 14 c of the pair of flanges 13. In this case, if the size of the bulge 16B is too large, the bulge 16B will prevent the plate core from directly contacting with the second sides 14 c, 14 c of the pair of flanges 13. On the other hand, in the illustrated embodiment, since the shape of the bulge 16B is managed stably as described above, excessive increase in size of the bulge 16B can be avoided. Therefore, the bulge 16B does not become an obstacle for this fixing. Therefore any assembly error of the plate core to the flanges 13 can be obviated.
Next, the covering of the winding 30 (each of the conducting wires 31) is partially stripped off. The stripping is performed by irradiating the covering for the portion directly facing the second pieces 47 and 57 at the end portion of the winding 30 temporarily fixed to each of the terminal electrodes 41, 42, 51 and 52. The covering to be irradiated is on the side opposite to the side directly facing the terminal electrodes 41, 42, 51, and 52. Irradiation is performed with a pulsed laser beam using a YAG laser irradiation device (not shown). More specifically, from the position above the area shown in FIG. 2, only one pulsed laser beam is applied for a duration of not more than 40 nsec. so that the covering is stripped off. The pulsed laser beam has a wavelength of 1064 nm, a pulse width of not more than 100 nsec, a frequency of 20 Hz, and an irradiation energy of 230 J/m2�10%, approximately.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS6154112 *Jul 9, 1999Nov 28, 2000Taiyo Yuden Co., Ltd.Chip inductorUS6157283 *Jan 25, 1999Dec 5, 2000Taiyo Yuden Co., Ltd.Surface-mounting-type coil componentUS6373366 *Sep 19, 2000Apr 16, 2002Tdk CorporationCommon mode filterUS6427315 *Jun 16, 1999Aug 6, 2002Murata Manufacturing Co., Ltd.Coil component and manufacturing method for the sameUS6535095 *Apr 18, 2001Mar 18, 2003Taiyo Yuden Co., Ltd.Wound type common mode choke coilJP2004014671A Title not availableJP2005093564A Title not availableJP2005142459A Title not availableJP2005322675A Title not availableJP2006121013A Title not availableJP2007067206A Title not availableJPH04369811A Title not availableJPH06141432A Title not availableJPH10153621A Title not availableJPS5792807A * Title not available* Cited by examinerNon-Patent CitationsReference1U.S. Appl. No. 11/812,053, filed Jun. 14, 2007 in the name of Yutaka Hatakeyama et al.Classifications U.S. Classification336/192International ClassificationH01F27/29Cooperative ClassificationH01F17/045, H01F41/10, H01F27/292European ClassificationH01F17/04C, H01F27/29BLegal EventsDateCodeEventDescriptionMay 30, 2012FPAYFee paymentYear of fee payment: 4Jun 14, 2007ASAssignmentOwner name: TDK CORPORATION, JAPANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HATAKEYAMA, YUTAKA;KAJIWARA, KOUZOU;REEL/FRAME:019461/0214;SIGNING DATES FROM 20070530 TO 20070612Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HATAKEYAMA, YUTAKA;KAJIWARA, KOUZOU;SIGNING DATES FROM 20070530 TO 20070612;REEL/FRAME:019461/0214RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google