JPS6041707Y2 - electromagnetic device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to improvements in electromagnetic devices, primarily ballasts for discharge lamps.

In general, this type of discharge lamp ballast has a coil attached to the center leg of an E-shaped core, which has a center leg and side legs set slightly longer than the center leg, and an I-shaped core on the end surface of the side legs of the E-shaped core.
It is constructed by interposing an epoxy resin adhesive in the leakage gap formed between the end side surfaces of the E-shaped core and the central leg end surface of the E-shaped core and the central side surface of the I-shaped core. .

By the way, epoxy resin adhesives are used to reduce noise caused by the vibration of the core facing the leakage gap, but the viscosity decreases significantly before the curing reaction occurs due to heating, so it is difficult to prevent leakage. Even if a sufficient amount of adhesive is placed in the gap, most of it will leak into the gap between the coil bobbin and the core, leaving a very small amount of adhesive, which will reduce the adhesion strength of the core in the leakage gap. There is a disadvantage that the noise characteristics are lowered and fully satisfactory noise characteristics cannot be obtained.

In view of these points, the present invention provides an electromagnetic device that can ensure a sufficient residual amount even if an epoxy resin adhesive is interposed in the leakage gap, and can also effectively improve noise characteristics. , Examples will be described below.

In FIGS. 1 and 2, reference numeral 1 denotes a bobbin molded from a resin material, and flanges 3 and 4 are integrally formed at both ends of a cylindrical portion 2. As shown in FIG.

A partition wall 5 is integrally formed at one end inside the cylindrical portion 2 so as to be flush with the outer surface of the flange portion 3, for example, and a plurality of small through holes 6 are formed in the partition wall 5. There is.

Note that the through hole 6 also includes a slit hole.

A coil 7 is formed by winding a wire around the cylindrical portion 2 of the bobbin 1 without using any interlayer insulation material.

Note that an interlayer insulating material can also be used in forming the coil 7.

8 is an E-shaped core, for example, the central leg 9 is the side leg 10.
The length is set slightly shorter than 10.

In this E-shaped core 8, the central leg 9 is inserted into the cylindrical part 2 with respect to the bobbin 1, and the side legs 10 and 10 are inserted into the coil 7.
It is attached so that it is located on the circumferential surface of the

Reference numeral 11 denotes an I-shaped core, the side surfaces of both ends of which are abutted against the end surfaces of the side legs 10, 10 of the E-shaped core 8.

A partition wall 5 serving as a leakage gap is located between the central side surface of the I-shaped core 11 and the end surface of the central leg 9 of the E-shaped core 8. An adhesive 12 is supported.

Note that the adhesive 12 also includes varnish used for varnish impregnation treatment.

In this way, the cylindrical part 2 of the bobbin 1 has a plurality of small through holes 6.
Since the partition wall 5 having E is integrally formed, for example, E
When the adhesive 12 is applied to the end face of the central leg 9 of the shaped core 8 and inserted into the cylindrical part 2, the adhesive 12 spreads over the entire end face of the central leg 9 and is also injected into the through hole 6 of the partition wall 5. Ru.

Therefore, even if the viscosity of the adhesive 12 decreases during thermal curing, its surface tension allows it to be sufficiently supported in the through holes 6, thereby improving the adhesive strength of the core and significantly improving noise characteristics.

Furthermore, since the partition wall 5 is integrally formed with the cylindrical portion 2 of the bobbin 1, when the core end face is fixed with the adhesive 12 via the partition wall 5, the core end face is also attached to the partition wall 5 with the adhesive 12. Due to the fixed relationship, the fixing property can be improved more than fixing simply by the adhesive 12, and the noise prevention effect can be enhanced.

Further, by setting the thickness of the partition wall 5 to match the leakage gap, adjustment of impedance characteristics can be simplified or omitted, and the assembly work can be performed more efficiently.

Moreover, since the bottom of the bobbin 1 is shaped by a mold, the thickness of the partition wall 5 can be easily set to a desired value.
Further effects can be expected from the simplification or omission of the characteristic adjustment described above.

Furthermore, although it is generally practiced to insert a paper material or the like into the leakage gap, in the case where the magnetic path is formed by an E-shaped or ■-shaped core, the paper material tends to fall out from the leakage gap.

However, since the partition wall 5 is integrally formed with the bobbin 1 as in the above structure, there is no chance of it falling off during the assembly process, and automatic assembly can be improved.

FIG. 3 shows another embodiment of the bobbin according to the present invention,
The bobbin 13 has flange parts 3 and 4 integrally formed at both ends of the cylindrical part 2, and a partition wall 5 having a through hole 6 is integrally formed in the central part of the cylindrical part 2.

E-shaped cores are attached to the bobbin 13 from the left and right sides.

According to this embodiment, since the partition wall 5 is formed in the central portion of the cylindrical portion 2, the ability to carry the adhesive is improved and the noise characteristics can be further improved.

In this regard, the present inventor tried to compare it with the conventional product and was able to confirm that the noise of the proposed product was 5 to 7 horns lower on average.

As described above, according to the present invention, by interposing the partition wall having a plurality of small through holes in the leakage gap portion, the adhesive carrying capacity can be improved and the low back noise characteristics can be significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, FIG. 2 is a perspective view of a bobbin according to the present invention, and FIG. 3 is a side sectional view showing another embodiment of the bobbin according to the present invention. In the figure, 1 and 13 are bobbins, 2 is a cylindrical part, 3 and 4 are flange parts, 5 is a partition wall, 6 is a through hole, 7 is a coil, 8 and 11 are cores, and 12 is an adhesive.

Claims (1)

[Scope of utility model registration request] A resin bobbin is formed, in which flanges are integrally formed at both ends of the cylindrical part, and partition walls having a plurality of small through holes are integrally formed in the cylindrical part, and a wire is wound around the cylindrical part of the bobbin. 1. An electromagnetic device comprising a formed coil and a plurality of cores disposed on both sides of a partition wall of a bobbin, and an adhesive is supported in a through hole in a partition wall portion of the bobbin.