JPH06290973A - Line filter - Google Patents

Abstract

PURPOSE:To provide a line filter having high performance and high safety in the line falter being inserted in a power circuit for various electronic equipment and preventing the intrusion and leakage of noises. CONSTITUTION:Two-split winding bobbins 4, in which projecting sections 2 are formed to collar sections, are incorporated into a square hollowed-shaped closed magnetic circuit core 1 and a pair of windings are carried out, and the magnetic core 1 is into a horizontal case 8, in which a plurality of movable tongue piece sections 10 and thin triangular rib sections 14 are formed to the core 1, the magnetic core 1 and the winding bobbins 4 are fitted and fixed to the horizontal case 8, and a stable line filter, in which no adhesive is used and deterioration with time of inductance is hardly generated and which has high safety, can be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line filter which is inserted in a power supply circuit of electronic equipment to prevent noise from entering and leaking.

[0002]

2. Description of the Related Art Generally, a line filter is mainly used to prevent a common mode noise component generated between a pair of lines in a power supply line and ground, and its electric circuit diagram is shown in FIG. That is, the line filter includes the pair of windings 17 so that the magnetic flux generated by the line current does not magnetically saturate the magnetic core 16 forming the closed magnetic circuit.
Are configured so that the magnetic fluxes generated by the line currents cancel each other out.

As an example of a concrete configuration of the line filter, as shown in FIGS. 15 and 16, on a magnetic leg of a square-shaped closed magnetic circuit core 18 made of a magnetic material having a high magnetic permeability such as ferrite, or on the sun. A winding bobbin 20 made of a resin molded body divided into two is incorporated on the central magnetic leg of the V-shaped closed magnetic circuit magnetic core 19, and a gear portion 21 provided on the end face or the central portion of the winding bobbin 20 is used. By rotating the winding bobbin 20, a pair of windings 17 are provided on the winding bobbin 20.

Next, the metal terminal 22 is inserted into the through hole provided in the flange portion of the winding bobbin 20, or the metal terminal 2 is inserted.
The terminal plate 23 made of the resin molded body 2 mounted on the metal core 22 is attached to the structural body made of the magnetic cores 18 and 19 and the winding bobbin 20, and the winding lead is wound around the metal terminal 22 and connected by soldering or the like. . Finally, in order to prevent rattling of the magnetic cores 18 and 19, the winding bobbin 20, and the terminal plate 23, an adhesive 24 or the like is used to fix them to form a line filter.

Further, a case is attached to the line filter shown in FIG. 16, the case, the terminal plate 23, and the letter-shaped closed magnetic circuit magnetic core 1 are attached.
There are also those configured as in JP-A-62-213222 and JP-A-61-205013, in which No. 9 is fixed.

[0006]

In the line filter having the above structure, the magnetic cores 18 and 19 are rotatable by 360 ° with respect to the bobbin 20, and the magnetic core 1 is fixed to fix the magnetic cores 18 and 19.
8 and 19 and the winding bobbin 20, or the magnetic cores 18 and 19 and the terminal plate 23 were fixed with an adhesive 24. As a result, stress in adhesive curing is applied to the magnetic cores 18 and 19,
Magnetic strain was generated in the magnetic cores 18 and 19 and deterioration of the inductance with time of about 5 to 30% occurred. Further, due to external shocks, vibrations, etc., the magnetic cores 18, 19 made of ferrite or the like, which are conductors, may be worst broken and fallen off, or the case may come off, so that sufficient safety cannot be ensured.

An object of the present invention is to eliminate the above-mentioned conventional drawbacks and provide a high-performance and highly safe line filter.

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention is provided on one magnetic leg of a closed-type closed magnetic circuit magnetic core with an integrated mouth or on a central magnetic leg of a closed closed magnetic circuit magnetic core of an integrated type. A two-divided winding bobbin that is mounted and has protrusions on the flanges at both ends, a pair of windings applied to this winding bobbin, and a movable body that fits these assembled components to the protrusions of the winding bobbin. The tongue portion, a rib portion for fixing the magnetic core on the inner wall, and an L-shaped movable tongue portion for preventing the magnetic core from moving are formed of a resin molded body case.

[0009]

With the above structure, when the structure consisting of the magnetic core and the wound bobbin is inserted into the case that covers the outer periphery thereof, the protrusion provided on the collar of the winding bobbin and the movable tongue provided on the case. By fitting and fixing one part, it is possible to prevent rattling in the insertion direction of the winding bobbin and the case, and to prevent it from coming off.Furthermore, the magnetic core is brought into contact with the rib part provided on the inner wall of the case, and the L-shaped movable connecting from the top By supporting the magnetic core with the tongue piece, it is possible to hold the magnetic core stably without rattling. For these reasons, the magnetic core, the winding bobbin, and the case can be fixed without using an adhesive, and the inductance due to adhesion will not change over time. It is possible to provide a line filter that is stable and highly safe against external shocks and vibrations without deterioration.

[0010]

1 is a perspective view of a line filter according to a first embodiment of the present invention.

As shown in FIG. 2, two to six projections 2 are provided on the flanges at both ends on one magnetic leg of the V-shaped integrated closed magnetic circuit core 1 made of a high magnetic permeability material such as ferrite. Two semicircular winding bobbins 4 made of a resin molded body having a gear portion 3 provided at the center or the end face are fitted and fixed by sandwiching two magnetic bobbins 4 with one magnetic leg in between.

Next, by rotating the gear part 3 of the winding bobbin 4 from the outside, the winding bobbin 4 is rotated and the insulating coating copper wire is provided in the two winding grooves of the winding bobbin 4. A pair of windings 5 are wound in the direction. The winding start and winding end lead wires 6 are wound around metal terminals 7 which are inserted and fixed after winding in through holes provided in the flanges of both ends of the winding bobbin 4, and are connected by soldering or the like. Alternatively, before winding, the metal terminal 7 is inserted into the winding bobbin 4 for winding, and after winding, the metal terminal 7 is moved by a required length to be a printed circuit board insertion terminal, and the winding start and winding are performed. The end lead wire 6 may be connected to the metal terminal 7.

Next, a horizontal case 8 made of a resin molded body for inserting and fixing the assembly structure of the V-shaped closed magnetic circuit magnetic core 1, the winding bobbin 4, and the winding 5 will be described below. Figure 3
Is a perspective view of the horizontal case 8 having an opening in one direction, FIG. 4 is a front view of the horizontal case 8, and FIGS. 5 and 6 are A- of FIG.
It is an A'sectional view and a BB 'sectional view. As shown in FIGS. 4 and 5, two notch tongues 9 having a width of about 2 to 5 mm are provided on the side surface of the horizontal case 8 and further directed downward from the top plate at a position symmetrical to the notch tongues 9. I own two movable tongues 10 that are extended.

The distance between the linear portions of the notch tongue portion 9 and the movable tongue portion 10 is set to be equal to or slightly larger than the distance between the protrusions of the collar portion of the winding bobbin 4, and the notch tongue portion 9, A taper portion 11 is provided at the upper end of the movable tongue portion 10 for fitting inwardly with the protrusion 2 of the collar portion of the winding bobbin 4 having a thickness of about 0.2 to 1 mm. Further, as shown in FIG. 6, two L-shaped movable tongue portions 12 extending downward from the top plate of the horizontal case 8 are provided for fixing the V-shaped closed magnetic circuit magnetic core 1, and the horizontal case 8 is provided. L-shaped movable tongue piece 12 from the inner surface of the top plate
The distance to the bent portion 13 is set to be equal to or slightly larger than the thickness of the magnetic leg of the V-shaped closed magnetic circuit magnetic core 1.

Further, a triangular thin rib portion 14 is provided at a symmetrical position on the inner side surface portion of the horizontal case 8 into which the mouth-shaped closed magnetic circuit magnetic core 1 is inserted, and the distance between the tips of the rib portions 14 is closed. It is set so as to be slightly smaller than the outer dimension or thickness of the magnetic leg of the magnetic core 1, and it is provided at 2 to 6 places.

As shown in FIGS. 7 and 8, in the horizontal case 8 having the above-described structure, the closed closed magnetic circuit magnetic core 1 and the coiled bobbin are arranged. Is oriented horizontally and is inserted from the opening of the horizontal case 8. The protrusion 2 of the collar of the winding bobbin 4 is inserted along the side surface of the horizontal case 8 and the movable tongue portion 10 extending downward from the top plate, and the protrusion 2 of the winding bobbin 4 is inserted into the horizontal case 8 The notched tongue portion 9 and the tapered portion 11 of the movable tongue portion 10 are further inserted while being expanded outwardly, and are fitted together as shown in FIG.

At this time, the horizontally closed V-shaped closed magnetic circuit magnetic core 1 is also inserted into the horizontal case 8 at the same time, and the L-shaped movable tongue portion 12 extending from the top plate is spread to further expand the horizontal shape. The thin triangular rib portion 14 provided on the inner surface of the case 8 is slightly shaved and inserted to fit the square V-shaped closed magnetic circuit magnetic core 1 into the horizontal case 8 as shown in FIGS. As described above, the winding bobbin 4, the square-shaped closed magnetic circuit magnetic core 1, and the horizontal case 8 are provided.
The line filter is constructed by inserting, fitting and fixing.

As another embodiment, a line filter may be constructed using a vertical case 15 having an opening in one direction, which is shown in a perspective view in FIG. 10 is a front view of the vertical case 15, and FIG. 11 is a sectional view taken along the line AA 'in FIG. Figure 10,
As shown in FIG. 11, four notch tongue portions 9 having a width of about 2 to 5 mm are provided on both sides of the vertical case 15, and the distance between the notch tongue portions 9 is the same as that of the collar portion of the winding bobbin 4. The distance between the protrusions 2 is set to be equal to or slightly larger than the distance between the protrusions 2. At the upper end of the notch tongue portion 9, the protrusion 2 of the collar portion of the winding bobbin 4 having a thickness of about 0.2 to 1 mm toward the inside is formed. A tapered portion 11 for fitting with is provided.

Above the vertical case 15, a space, which is set to be slightly larger than the outer shape and thickness of the magnetic leg for accommodating the V-shaped closed magnetic circuit magnetic core 1, is provided inside the vertical case 15, and as shown in FIG. Triangular thin rib portions 14 are set at symmetrical positions on the side surface portions so that the distance between the tips of the rib portions 14 is slightly smaller than the outer dimension or thickness of the magnetic leg and provided at 4 to 6 places.

As shown in FIG. 12, a structure composed of the V-shaped closed magnetic circuit magnetic core 1 and the wound bobbin is placed in the vertical case 15 having the above-described structure in the upward direction. As shown in FIG. 12, the protrusion 2 provided on the flange of the winding bobbin 4 and the notch tongue of the vertical case 15 are inserted in the opening of the vertical case 15 as shown in FIG. The taper portion 11 of the piece portion 9 is fitted, and at the same time, the upper magnetic leg of the V-shaped closed magnetic circuit magnetic core 1 is inserted while slightly scraping the thin-walled triangular rib portion 14 provided in the vertical case 15. The wire bobbin 4 and the V-shaped closed magnetic circuit magnetic core 1 are inserted into the vertical case 15 and fitted and fixed to form a line filter as shown in FIG.

The above-mentioned configuration has been described with reference to the embodiment in which the line filter is constructed by using the square V-shaped closed magnetic circuit magnetic core 1.
Instead of the mouth-shaped closed magnetic circuit core 1, a day-shaped closed magnetic circuit core is used, a winding bobbin is attached to the central magnetic leg, and after winding and wiring, it is inserted into the same horizontal or vertical case as above. A similar line filter can be configured by fitting and fixing.

In the line filter constructed as described above, the stress applied to the magnetic core is smaller than that in the conventional line filter in which the magnetic core and the winding bobbin or the magnetic core and the terminal plate are fixed with an adhesive or the like. Almost no magnetic distortion occurs, and the deterioration of inductance with time is extremely small. Further, since the magnetic core is covered by the case against external impacts and vibrations, the stability is high, and there is no problem that the magnetic core falls off.

Further, the horizontal case 8 and the vertical case 15 are formed by molding a mixture of a magnetic powder such as ferrite powder and a resin material, and a line filter is formed. Electromagnetic noise radiated from the magnetic core material to the surroundings or electromagnetic noise coupled to the line filter from the outside, the horizontal case 8,
Alternatively, the vertical case 15 can be electromagnetically shielded, and an additional effect is obtained in that unnecessary electromagnetic radiation to the surroundings or coupling of external noise can be reduced.

[0024]

With the above-mentioned structure, the present invention provides
By fitting and fixing the magnetic core and winding bobbin in the resin case by combining multiple movable tongues and thin-walled triangular ribs, the stress applied to the magnetic core material is small, and there is almost no deterioration of inductance over time. It is possible to improve the performance of. Furthermore, it is stable to external shocks and vibrations, has high safety, and has good workability in assembly, and is of great industrial value.

[Brief description of drawings]

FIG. 1 is a perspective view of a line filter according to an embodiment of the present invention.

FIG. 2 is a perspective view for explaining the assembly of the line filter.

FIG. 3 is a perspective view of a horizontal case used for the line filter.

FIG. 4 is a front view of the horizontal case.

5 is a sectional view taken along the line AA ′ of the horizontal case shown in FIG.

6 is a cross-sectional view taken along line BB ′ of the horizontal case shown in FIG.

FIG. 7 is a sectional view of the line filter.

FIG. 8 is a bottom view of the line filter.

FIG. 9 is a perspective view of a vertical case used for the line filter.

FIG. 10 is a front view of the vertical case.

FIG. 11 is a sectional view of the vertical case.

FIG. 12 is a sectional view of the line filter.

FIG. 13 is a perspective view of the line filter.

FIG. 14 is a circuit diagram of a general line filter.

FIG. 15 is a perspective view of a conventional line filter.

FIG. 16 is a perspective view of a conventional line filter.

[Explanation of symbols]

 1 Closed magnetic circuit magnetic core 2 Protrusions 3 Gears 4 Winding bobbins 5 Windings 6 Lead wires 7 Metal terminals 8 Horizontal cases 9 Notched tongues 10 Movable tongues 11 Tapered parts 12 Movable tongues 13 Bent part 14 Rib part 15 Vertical case

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI Technical display location H01F 41/06 E 8019-5E (72) Inventor Tatsuya Mori 1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. Within

Claims (2)

[Claims] 1. A two-divided type, which is mounted on one magnetic leg of a closed-ended magnetic circuit core with an integrated mouth or on a central magnetic leg of a closed closed-circuit magnetic core with an integrated Japanese character, and is provided with protrusions at both end flanges. A winding bobbin,
A pair of windings applied to this winding bobbin, and a movable tongue portion that covers the outer periphery of these assembled components and has an opening in one direction and that fits on the protruding portion of the winding bobbin, on the inner wall L connected to the rib for fixing the magnetic core and the top plate for preventing the magnetic core from moving
A line filter including a case formed of a resin molded body provided with a character-shaped movable tongue portion. 2. The line filter according to claim 1, wherein a case is formed by molding a mixture of magnetic powder such as ferrite powder and a resin material.