JP2004103862A - Wound coil component, and method of connecting coil conductor and metal terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the problems caused by welding of the end of a coil conductor and a metal terminal, while preventing increase of the component size. <P>SOLUTION: The end part 7a (7b) of the coil conductor to be connected to the metal terminal 5a (5b) is thinned by machining. The metal terminal 5a (5b) is brought into contact with the thinned end 7a (7b) of the coil conductor and is welded thereto, resulting in a compact joint between the end 7a (7b) of the coil conductor and the metal terminal 5a (5b). Since the end 7a (7b) of the coil conductor to be welded is reduced in volume, energy required for welding can be reduced. Moreover, since the quantity of heat to be applied to the end 7a (7b) of the coil conductor at the time of welding can also be reduced, transmission of excessive heat from the end 7a (7b) of the coil conductor to other parts of the coil conductor applied with different coating can be suppressed, resulting in preventing the thermal deterioration of the coating of the coil conductor and thereby reducing shorting problems of the coil. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wire-wound coil component having a coil formed by winding a conductive wire, and a method for connecting a conductive wire of the coil to a metal terminal.
[0002]
[Background Art]
FIG. 6 shows an example of a wound coil component (see Patent Document 1). The coil-type coil component 20 is of a surface-mount type that is surface-mounted on a circuit board or the like and incorporated into a circuit. In the wire-wound coil component 20, a coil 22 is wound around a coil bobbin 21 to form a coil 23. A metal terminal 24 is attached to the coil bobbin 21. The metal terminal 24 is entangled with an end 22a of a winding 22 forming a coil 23, and the metal terminal 24 is connected to the winding end 22a. Are connected by welding. For example, the coil 23 can be connected to an external circuit via the metal terminal 24 by surface-mounting the wound coil component 20 at a set position on the circuit board.
[0003]
[Patent Document 1]
JP 2001-93746 A
[Problems to be solved by the invention]
By the way, as a coil component that can be incorporated in a circuit of a power supply device, for example, a coil component that can conduct a larger current is required. In response to this demand, there is a type in which the diameter of the winding 22 of the coil 23 is increased.
[0005]
However, this increase in diameter causes the following problem. The problem is that, for example, surface mount components such as the coil type coil component 20 are required to be reduced in size. In order to meet this requirement, it is difficult to increase the size of, for example, the metal terminal 24 of the coil-type coil component 20. Since the diameter of the winding 22 is increased in such a situation, the thickness of the winding 22 is too large relative to the size of the metal terminal 24, and the winding end 22 a is entangled with the metal terminal 24. This makes it difficult to do so. Even if the winding end 22a can be entangled with the metal terminal 24, the connection between the winding end 22a and the metal terminal 24 becomes large because the winding end 22a is thick. There is a problem that the miniaturization of the wound coil component 20 is hindered.
[0006]
Further, when welding the winding end 22a and the metal terminal 24, if the winding end 22a is thick, the energy required to melt the winding end 22a increases. Furthermore, since the amount of heat supplied to the winding end 22a during welding increases, the amount of heat conducted from the winding end 22a to other parts of the winding 22 increases. The winding 22 of the coil 23 is a covered conductor in which a covering is applied to the conducting wire. The covering of the winding end 22 a is removed and the covering end is welded to the metal terminal 24. When excessive heat is transferred from the winding end 22a to another portion of the winding 22 (that is, a portion where the coating is applied), the heat deteriorates the coating of the winding 22 and causes a short circuit problem. May occur.
[0007]
The present invention has been made to solve the above-described problems, and an object of the present invention is to reduce the size of a coil-type coil component while preventing a problem caused by welding between a coil conductor and a metal terminal. It is an object of the present invention to provide a wire-wound coil component capable of satisfactorily connecting the conductive wire and the metal terminal, and a method for connecting the conductive wire of the coil and the metal terminal.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides means for solving the above problems with the following configuration. That is, a wire-wound coil component according to the present invention is a wire-wound coil component having a coil formed by winding a wire and a metal terminal connected to the wire end of the coil. The terminals are connected by welding, and the end of the lead wire to be welded to the metal terminal is cut and thinned.
[0009]
Further, in the method of connecting a conductor of a coil and a metal terminal according to the present invention, the end of the conductor forming the coil is cut and thinned, and then the metal terminal is brought into contact with the end of the thinned conductor, It is characterized in that a contact portion between the end of the conductive wire and the metal terminal is joined by welding.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0011]
As shown in FIG. 3, the wound coil component of this embodiment has a configuration in which a coil 3 formed by winding a winding 2 is embedded in a block 4 made of a magnetic material. The winding 2 is a covered conductor in which a conductor such as copper, silver or gold is coated with an insulating material such as polyurethane. The diameter of the coated conductor is 0.6 mm or more and 1.5 mm or less. In this embodiment, the coil 2 is wound to form a coil 3 so as to fit within a region having an area of, for example, 13 mm × 13 mm or less.
[0012]
The wire-wound coil component 1 is provided with metal terminals 5 (5a, 5b) for connecting the coil 3 to the outside. Both ends 6a and 6b of the winding 2 of the coil 3 are stripped of the coating to expose the conductor, and a part of the metal terminals 5a and 5b is welded to the bare conductors 6a and 6b, respectively. The welded portions between the bare conductor portions 6a and 6b at the coil ends and the metal terminals 5a and 5b are buried inside the block body 4. Further, a part of the metal terminals 5 a and 5 b is disposed so as to be exposed to the outside of the block body 4. The externally exposed portions of the metal terminals 5a and 5b are arranged along the side surfaces of the block body 4, and the tips are bent toward the bottom surface. The coil-type coil component 1 of this embodiment is a surface-mount component, and a portion disposed on the bottom surface side of the metal terminals 5a and 5b forms an external connection portion for connecting to a circuit on a circuit board. .
[0013]
The most characteristic feature of this embodiment is that, as shown in FIG. 1, in the bare conductor portions 6a and 6b at the ends of the winding 2 of the coil 3, the portions 7a and 7b connected to the metal terminals 5 are cut. It is thinner by processing. In addition, the code | symbol 10 in FIG.
[0014]
The amount removed by cutting at the wire ends 7a and 7b connected to the metal terminal 5 is determined by various conditions such as the diameter of the bare wire of the winding 2 and the size and thickness of the metal terminal 5, Although not particularly limited, for example, for example, for example, 25% or more of the volume before processing is removed by cutting. That is, the ends 7a and 7b of the conductive wires connected to the metal terminals 5 are reduced to, for example, 75% or less of the volume before cutting by cutting.
[0015]
As a method of cutting the ends 7a, 7b of the winding 2 connected to the metal terminals 5a, 5b, for example, there is a method of cutting like a pencil sharpener. There is also a method of crushing the ends of the bare conductor portions 6a and 6b, thereby removing both sides of the flat conductor end. In this case, the cut portion has a substantially square cross-sectional shape. As described above, there are various methods for cutting the end portion of the conductive wire, and any of the methods may be employed here.
[0016]
In this embodiment, since the winding 2 is too thick with respect to the size of the metal terminals 5a and 5b in order to increase the diameter of the winding 2, the winding 2 is not entangled with the metal terminals 5a and 5b. Is difficult. For this reason, as shown in FIG. 2, the metal terminals 5 a and 5 b are wound around the winding 2. In this embodiment, the wire ends 7a and 7b of the winding 2 are thinned by cutting, and the metal terminals 5a and 5b are formed on the circumferential surfaces of the wire portions 7a and 7b whose diameters are reduced in the circumferential direction. And then crimped and then joined by, for example, arc welding. In FIG. 2, reference numeral 12 denotes an electrode used in arc welding, and reference numeral 13 denotes a ground.
[0017]
According to this embodiment, the winding 2 of the coil 3 is made thicker with respect to the size of the metal terminals 5a and 5b due to the increase in diameter, so that the winding 2 is entangled with the metal terminals 5a and 5b. Instead, a metal terminal is wound around the winding 2. Thereby, the end portions 7a, 7b of the winding 2 and the metal terminals 5a, 5b can be firmly welded while avoiding an increase in the size of the wound coil component 1.
[0018]
Further, in this embodiment, since the wire ends 7a, 7b of the coil 3 connected to the metal terminals 5a, 5b are thin, the volume of the wire portions 7a, 7b heated when welding is reduced. Thereby, the energy required for welding can be reduced. In addition, since the amount of heat supplied to the ends 7a and 7b of the coil 3 during welding is reduced, the amount of heat conducted from the ends 7a and 7b of the coil 3 to other portions of the winding 2 is reduced. Thereby, it is possible to prevent thermal deterioration of the coating of the winding 2 due to heating during welding. Thereby, the short-circuit problem of the winding 2 of the coil 3 can be avoided.
[0019]
Hereinafter, an example of a manufacturing process of the coiled coil component 1 will be described with reference to FIG. For example, first, as shown in FIG. 4A, the coil 2 is formed by winding the winding 2. Then, the coating on both ends of the winding end and the winding start of the winding 2 of the coil 3 is removed, and the above-mentioned cutting is performed to make the winding thin. Alternatively, when the length necessary for forming the coil 3 is known, for example, the winding 2 having a length necessary for forming the coil is prepared. Then, the coil 3 may be formed by winding the winding 2 after removing the coating on both ends of the winding 2 and cutting it to make it thin.
[0020]
Metal terminals 5a and 5b are wound around the respective ends 7a and 7b of the winding 2 of the coil 3 to make surface contact, and then swaged. Thereafter, the contact portions between the ends 7a and 7b of the winding 2 and the metal terminals 5a and 5b are welded by arc welding.
[0021]
Thereafter, the coil 3 and the metal terminals 5a and 5b are set in a mold. Then, the magnetic material powder is filled in the mold. For example, the magnetic material powder has a resin layer formed on the surface of pure iron powder or sendust powder. The magnetic material powder preferably has an average particle size of 20 μm or less from the viewpoint of improving the inductance characteristics of the coil-type coil component 1.
[0022]
Thereafter, the magnetic material powder is molded under pressure with a pressure in the range of, for example, 1 to 10 t / cm ² , and heat-treated to form a block 4 of magnetic material in which the coil 3 is embedded as shown in FIG. Is molded. External connection portions of the metal terminals 5a and 5b protrude from the block body 4.
[0023]
Thereafter, as shown in FIG. 4C, the portions of the metal terminals 5a and 5b protruding from the block body 4 are bent along the surface of the block body 4. In this way, the wound coil component 1 can be manufactured.
[0024]
It should be noted that the present invention is not limited to this embodiment, but can adopt various embodiments. For example, in this embodiment, the metal terminals 5a and 5b are wound around the entire periphery of the cut wire ends 7a and 7b, respectively, and welded to the wire ends 7a and 7b. However, for example, as shown in FIG. 5, the metal terminals 5 a and 5 b may be configured to be in surface contact with a part of the peripheral surface of the conductive wire ends 7 a and 7 b in a circumferential direction and welded. Alternatively, if the welding strength can be increased, for example, the metal terminals 5a and 5b may be welded to the conductor ends 7a and 7b in line contact.
[0025]
Further, in this embodiment, the coil 2 is formed by winding the coil 2 so as to fit within a region having an area of 13 mm × 13 mm or less, but the size of the coil 3 is not limited. Furthermore, in this embodiment, the winding 2 has a circular cross section. However, the shape of the winding 2 is not limited to the shape shown in this embodiment. 2 or the like may be used. Further, in this embodiment, the winding 2 has a diameter in the range of 0.6 mm or more and 1.5 mm or less, but the winding 2 having a thickness outside the range is used. Even in the adopted coil-type coil component, the end of the conductive wire connected to the metal terminal in the winding 2 may be made thin by cutting.
[0026]
Furthermore, in the wound type coil component 1 of this embodiment, the connection portions of the conductor ends 7a and 7b of the coil 3 and the metal terminals 5a and 5b are embedded in the block body 4. May be arranged outside.
[0027]
Furthermore, in this embodiment, the example in which the coil 3 is buried inside the block body 4 has been described. However, the present invention is not limited to this. The present invention can be applied to a wound coil component.
[0028]
【The invention's effect】
According to the present invention, since the end of the conductive wire of the coil to be welded to the metal terminal is cut and thinned, the volume of the end of the conductive wire to be welded to the metal terminal is reduced. Energy can be reduced. Also, when welding, the amount of heat supplied to the end of the conductor of the coil is reduced, so that the amount of heat transmitted from the end of the conductor to another portion of the coil, for example, to which the coating is applied, is reduced. Therefore, it is possible to prevent thermal deterioration of the coating of the coil conductor due to heating of the conductor during welding. As a result, the problem of short-circuiting of the coil wire can be suppressed.
[0029]
If the diameter of the coil wire is large, for example, the diameter of the coil wire is 0.6 mm or more and 1.5 mm or less, the wire to be welded to the metal terminal is used. Since the volume of the end is large, an energy problem or a short circuit problem due to welding is likely to occur. On the other hand, in the present invention, since the end of the coil wire to be welded to the metal terminal is made thin, even if the wire of the coil becomes thick, it is possible to suppress the occurrence of a problem due to welding.
[0030]
Furthermore, if the thickness of the coil wire is too large with respect to the size of the metal terminal due to the increase in the diameter of the coil wire, the metal terminal is formed in at least a part of the peripheral surface of the wire end portion of the cut coil in the circumferential direction. By welding in a surface contact along the direction, the connection portion between the metal terminal and the end of the coil conductor can be reduced. Thus, it is possible to prevent an increase in the size of the wound coil component. In addition, since the metal terminal and the end of the coil lead are in surface contact, the metal terminal and the end of the coil lead can be satisfactorily and firmly welded. Therefore, in a coiled coil component having a coil made of a large-diameter wire and capable of conducting a large current, it is possible to provide a small-sized coiled coil component having high reliability in connection between a metal terminal and an end of the coil wire. be able to.
[0031]
In the case where the conductor wire end and the metal terminal are connected by arc welding, an energy problem or a short circuit problem due to the above-described welding is likely to occur. Very effective.
[0032]
In addition, the surface-mount type, for example, a coil-type coil component having a configuration in which the coil is buried inside a block body made of a magnetic material, has a small size of the component itself, and thus is caused by welding. Although the problem and the problem due to the increase in the diameter of the coil wire are likely to occur, by employing the configuration of the present invention, it is possible to suppress the occurrence of such a problem while reducing the size of the wound coil component. it can.
[0033]
Further, in the case where the magnetic material of the block body of the wound coil component is made of a metal magnetic material, characteristics such as the inductance characteristics of the wound coil component can be improved.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of a unique configuration according to an embodiment of the present invention.
FIG. 2 is a view for explaining an example of a welded connection between a wire end of a coil and a metal terminal in the wire-wound coil component of the embodiment.
FIG. 3 is a perspective view schematically showing a wound coil component of the embodiment.
FIG. 4 is a diagram illustrating an example of a manufacturing process of the wound coil component of the embodiment.
FIG. 5 is a diagram for explaining another embodiment.
FIG. 6 is a model diagram showing a conventional example of a wound coil component.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Winding type coil part 2 Winding 3 Coil 4 Block body 5a, 5b Metal terminal 7a, 7b Metal terminal connection conductive wire part

Claims (7)

In a wire-wound coil component having a coil formed by winding a conductive wire and a metal terminal connected to the conductive wire end, the conductive wire end of the coil and the metal terminal are connected by welding. A wire-type coil component wherein a wire end to be welded to a terminal is cut and thinned. 2. The wire-wound coil component according to claim 1, wherein the metal terminal is welded to at least a part of the peripheral surface of the end portion of the conducting wire which has been subjected to the cutting process in a surface contact along a circumferential direction. 3. The wire-wound coil component according to claim 1, wherein a diameter of a conductive wire forming the coil is in a range of 0.6 mm or more and 1.5 mm or less. 4. The wire-wound coil component according to claim 1, wherein an end of the coil and the metal terminal are connected by arc welding. The coil is configured to be buried inside a block made of a magnetic material, and the welded portion between the conductor wire end and the metal terminal is buried inside the block, and the external connection part of the metal terminal is connected to the block. The wire-wound coil component according to any one of claims 1 to 4, wherein the wire-wound coil component is disposed so as to be exposed to the outside. 6. The wire-wound coil component according to claim 5, wherein the magnetic material of the block in which the coil is embedded is a metal magnetic material, and the block is formed by press molding. Cutting the wire end forming the coil to make it thinner, then contacting the metal terminal with the thinned wire end, and joining the contact portion between the wire end and the metal terminal by welding. Characteristic method of connection between coil wire and metal terminal.

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