JPH09232154A - Inductance element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inductance element capable of reducing the thickness and dealing with a large current easily. SOLUTION: This inductance element is composed of a bobbinless coil 1 made up of flat type copper wire, an iron core consisting of an E-shaped core 2 and an I-shaped core 3 made of magnetic substances, and a holder 4 made up of heat-resisting resin. Here, the lead wires 1a of the bobbinless coil 1 pass leading-out holes 4a provided in the holder 4, are bent on the external surface of the holder, 4 and are wired to the bottom surface of the holder 4. And the ends of the leads 1a are fixed so as to adhere closely to the bottom surface of the holder 4 to become surface-mounting terminals. Besides, cut-off parts 4b are provided at the upper surface of the holder 4 which touches the four corners of the core, and the E-shaped core 2, the I-shaped core 3, and the holder 4 are fixed simultaneously by applying an adhesive agent, etc., to the cut-off parts 4b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a choke coil used for a switching power supply or the like.

[0002]

2. Description of the Related Art A conventional inductance element will be described with reference to the drawings. FIG. 10 shows a coil of a conventional inductance element. FIG. 11 shows a coil of another conventional inductance element. The conventional inductance element has a structure in which a coil formed by winding a copper wire around a bobbin made of resin or the like and a magnetic core are combined, or a thin strip conductor such as a copper plate is punched as shown in FIG. A method of producing a turn coil 51 and combining a plurality of the one-turn coils 51 to form a coil having several turns or dozens of turns and combining with a magnetic core to form an inductance element, or a continuous method as shown in FIG. There has been a method of forming an inductor by combining a conductor made of a copper plate or the like with a bending process to form a coil.

Further, in response to the demand for a swing choke having an L-shaped or linearly decreasing inductance with respect to a DC current, the middle leg of the magnetic core is conventionally processed into a T-shaped or L-shaped. I made a swing choke.

[0004]

SUMMARY OF THE INVENTION In the conventional configuration,
It is difficult to reduce the thickness of the inductance element using the bobbin due to the thickness of the bobbin for insulation. Also,
The coil configured by combining the one-turn coils shown in FIG. 10 can be thinned as an inductance element. However, in the combination of the one-turn coil and another one-turn coil, the connection of the coil-to-coil connecting portion 52 is performed. Since resistance is generated, the DC resistance of the coil increases, which is a problem. Further, in the structure shown in FIG. 11 in which a thin conductor such as a copper plate is bent to form a coil, the bent portions 61 of the conductors are overlapped with each other, so that the coil becomes thick.

Further, when manufacturing a swing choke,
Swing characteristics can be achieved by processing the magnetic core,
To process the middle leg of the magnetic core into a T-shape or L-shape,
A special cutting machine etc. was required, and processing precision was required. INDUSTRIAL APPLICABILITY The present invention provides an inductance element which can be thinned and whose current capacity can be increased, does not require special processing of the magnetic core, can be easily processed into a coil terminal, and can be easily mounted on a mounting board. is there.

[0006]

DISCLOSURE OF THE INVENTION According to the present invention, a coil in which a wide flat plane of a rectangular copper wire is substantially perpendicular to the winding axis direction, and a magnetic core made of a magnetic material whose central leg is substantially circular are provided. In a magnetic component formed by combining the above, the winding start and winding end leads of the coil are bent along the outer surface of the holder through the lead-out holes formed in the holder made of resin, and are led to the bottom surface of the holder. It becomes a board mounting terminal. In addition, the number of turns of the coil is 0.
The number of windings is added by 5 times, and the coil that is configured so that the winding start and winding ends are almost in a straight line when viewed from the top surface of the coil and the magnetic core in which the length of the central leg is shorter than the length of the side leg are combined. It is an inductance element.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The inductance element of the present invention
By winding the wide flat surface of the flat copper wire almost at right angles to the winding axis direction, it becomes easy to reduce the thickness of the coil, and the wound flat copper wire forming the coil is used as a coil. Since the shape can be retained without the bobbin, a coil without a bobbin can be manufactured, and the space factor of the coil can be improved by the thickness of the bobbin, thus reducing the size and thickness and increasing the allowable current. Can be planned.
Further, the holder made of insulating resin is provided with the hole for drawing out the coil, becomes a hole for leading out the lead at the beginning and end of winding of the coil, and the lead passing through the hole is bent along the outer surface of the holder, The terminal end is arranged on the bottom surface of the holder and becomes a terminal for mounting on the board.

Further, the number of turns of the coil is 0.
By adding 5 turns and combining the magnetic cores with shorter middle legs compared to the outer legs, the magnetic path except the middle leg of the core with a gap forms a closed magnetic path at low current. The coil becomes a through coil with one turn,
It produces a larger inductance than that produced by the coil wound around the gapped middle leg.
In addition, since the wound coil has a gap in the middle leg of the magnetic core, the magnetic core does not saturate against a large current and an inductance can be generated, and an inductance having a swing characteristic with respect to a current can be obtained. It is a thing.

[0009]

Embodiments of the inductance element according to the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a component structure of an embodiment of an inductance element of the present invention. FIG. 2 shows FIG.
3 is a perspective view of the inductance element of the present invention shown in FIG.
FIG. 3 is a perspective view of a coil used in another embodiment of the inductance element of the present invention. FIG. 4 is a perspective view of another embodiment of the inductance element of the present invention incorporating the coil shown in FIG. FIG. 5 shows a DC superimposition characteristic diagram of another embodiment of the inductance element of the present invention.

As shown in FIGS. 1 and 2, the inductance element of the present invention is for leading out a lead and a magnetic core made of a bobbinless coil 1 made of a rectangular copper wire, an E type core 2 made of a magnetic material, and an I type core 3. The holder 4 is made of a heat resistant resin and has a hole 4a. The lead wire 1a of the bobbinless coil 1 passes through the lead-out hole 4a formed in the holder 4, is bent at the outer surface of the holder 4, and is wired to the bottom surface of the holder 4. The end of the lead 1a led out to the bottom surface of the holder 4 is fixed so as to be in close contact with the bottom surface of the holder 4, and serves as an optimum terminal for surface mounting. Also, the joint 4c of the holder 4 is
The structure is sandwiched between the E-shaped core 2 and the I-shaped core 3, and the notch 4 is formed on the upper surface of the holder 4 in contact with the four corners of the magnetic core.
b is provided, and the E core 2, the I core 3 and the holder 4 can be fixed at the same time by applying an adhesive or the like to the cutout portion 4b.

The coil 11 shown in FIG. 3 represents the number of turns of the coil added to the positive number of turns by 0.5.
FIG. 4 shows an inductance element of the present invention in which the coil 11 is incorporated into an E-shaped core 12, an I-shaped core 13 and a holder 14 in which a gap is formed in the middle leg of the magnetic core. Table 1
10 is a comparison of direct current resistance between the coil shown in FIG. 3 according to the present invention and the conventional coil shown in FIG. 10 under the same conditions.

[Table 1] As compared with Table 1, it is inevitable that the coil made by laminating the conductor consisting of the conventional one-turn coil is 1
Although the direct current resistance is high at the connection between the turn coils, the coil according to the present invention has a lower direct current resistance than the conventional coil because the coil is made of a continuous conductor.

The E-shaped core 1 having a gap in the middle leg
2 and the I-shaped core 13, the coil 11 of the present invention shown in FIG.
As shown in FIG. 5, the DC superimposition characteristics in the case of incorporating is a curve having an L-shaped inductance with respect to the DC current. 6 and 8 are diagrams simply expressing the function of the inductance element according to the present invention shown in FIG. 4, and FIGS. 7 and 9 are the DC superposition characteristic diagrams of FIGS. 6 and 8. . When the direct current flowing through the coil 11 shown in FIG. 3 is small, a magnetic flux 25 having a magnetic path in the middle leg of the E-shaped core provided with the gap 24 is also generated. The magnetic core excluding the legs becomes a substantially closed magnetic path with respect to the coil 11, and a magnetic flux 26 larger than the magnetic flux 25 is generated in the closed magnetic path. Therefore, it is substantially represented by the one-turn through coil 21 as shown in FIG. Since the magnetic path of the through coil 21 is a closed magnetic path, it has a characteristic that the inductance sharply decreases with respect to the current as shown in FIG. Further, when a relatively large current flows through the coil 11, the magnetic flux 26 in the magnetic path formed by the magnetic core excluding the middle leg with the gap of the E-shaped core shown above is saturated, so that no inductance is generated. This is not possible, and thereafter, the inductance shown in FIG. 9 is generated by the magnetic flux 25 generated by the coil 21 wound around the middle leg provided with the gap 24 as shown in FIG. That is, it is possible to manufacture an inductance element having an L-shaped direct current superposition characteristic, which has a high inductance at a low current and can generate an inductance even for a relatively high current.

[0013]

As described above, according to the present invention, since the coil forming the inductance element can reduce the bobbinless and the direct current resistance, it is easy to make the inductance element thin and increase the current of the coil. To do. Furthermore, the terminals located on the bottom of the holder are
It is composed of flat conductors and has a structure suitable for a mounting board. Further, since no special processing of the core is required, it is possible to reduce the man-hours for processing the core and provide an inexpensive swing choke coil.

[Brief description of drawings]

FIG. 1 is a perspective view of a fixture configuration of an embodiment of an inductance element of the present invention.

FIG. 2 is a perspective view of an embodiment of the inductance element of the present invention in FIG.

FIG. 3 is a perspective view of a coil used in another embodiment of the inductance element of the present invention.

FIG. 4 is a perspective view of another embodiment of the inductance element of the present invention.

FIG. 5 is a DC superimposition characteristic diagram of another embodiment of the inductance element of the present invention.

FIG. 6 is a diagram simply expressing the function of another embodiment of the inductance element of the present invention at a low current.

FIG. 7 is a DC superposition characteristic diagram of FIG.

FIG. 8 is a diagram simply expressing the function of another embodiment of the inductance element of the present invention when a relatively large current is applied.

9 shows the DC superposition characteristic of FIG.

FIG. 10 is a plan view of a part view and a completed view of a coil used in a conventional inductance element.

FIG. 11 is a plan view of a part view and a completed view of a coil used in another conventional inductance element.

[Explanation of symbols]

 1 bobbinless coil 1a lead 2 E-type core 3 I-type core 4 holder 4a lead-out hole 4b notch 4c joint 11 bobbinless coil 11a lead 12 E-type core 13 I-type core 14 holder 21 1-turn coil 22 E-type core 23 I-type core 24 Gap 25 Magnetic flux 26 Magnetic flux 51 1 Turn coil 52 Connection part 61 Overlapping part

Claims (2)

[Claims] 1. A magnetic component comprising a coil wound in such a manner that a wide flat plane of a rectangular copper wire is substantially perpendicular to a winding axis direction, and a magnetic core made of a magnetic material whose central leg is substantially circular. Leads at the beginning and end of winding of the coil are bent along the outer surface of the holder through a lead-out hole formed in a holder made of resin, and lead out to the bottom surface of the holder to serve as board mounting terminals. And an inductance element. 2. The number of windings of the coil is set to the number of windings obtained by adding 0.5 to the integer number of windings, and the leads at the beginning and end of winding are arranged in a substantially straight line when viewed from the upper surface of the coil, and a center portion The inductance element according to claim 1, which is combined with a magnetic core having a leg length shorter than a side leg length.