JPS6214624Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] This invention uses an internal filter in audiovisual equipment such as a television receiver to reduce noise signals that enter the equipment via the power cord. A chiyoke coil was installed as a
Regarding the plug.

[Technical background of the invention]

For example, in a television receiver, if interference radio waves having a wide range of frequency components are emitted from internal wiring, circuit elements, etc., it may adversely affect the quality of image reception and sound quality. In order to prevent such noise signals from entering the circuit, measures are taken such as shielding each circuit element and providing a noise filter in each circuit.

In a power supply unit, which is one of the paths through which jamming waves can enter, the power cord itself becomes an antenna, and jamming waves can sometimes flow into the circuitry inside the device via the power line. To prevent this, a filter such as a choke coil may be provided in the plug of the power cord.

FIG. 1 shows a conventional example in which a filter is inserted into the plug of the power cord. That is, one end of the conducting wire 111 of a chiyoke coil 121 formed by spirally winding a conducting wire 111 around a cylindrical magnetic body 101 is connected to the terminal portion 141 of the electrode blade 131, and the other end is connected to one of the lead wires of the cord 15. Connect to 151. Similarly, magnetic material 10
2. A chiyoke coil 122 made up of a conducting wire 112 connects one end of the conducting wire 112 to the electrode blade 13.
2, and the other end is connected to the cord 15.
It is connected to another leader line 152 of. The two tie-yoke coils 121 and 122 are fixed side by side to a main body 171 of a T-shaped holder 17 made of an insulating material by a locking tool 16. Also, the electrode blade 131,1
32 is integrally fixed to the head 172 of the T-shaped holder 17 with respective terminal portions 141 and 142. The plug connected and arranged as described above is molded using a flexible insulating member with the electrode blades 131 and 132 protruding, and the plug body 1 is molded using a flexible insulating member.
8. At this time, the leader line 15 of the code 15
In order to prevent the plug body 18 from breaking due to an external force applied to the cord 15 during use, the plug body 18 is configured to surround and fix the covering member of the cord 15.

As mentioned above, each leader line 151, 1 of the code 15
52 and electrode blades 131, 132, respectively, to reduce the interference radio waves flowing into the device via the power cord.

[Problems with background technology]

However, in the above-mentioned plug, since there is a practical restriction on the size of the plug body, the two York coils must be placed close to each other. As a result, the electromagnetic induction effect between the chiyoke coils causes the chiyoke coil to beat, and magnetostrictive vibrations increase. In addition, the electric characteristics of the chiyoke coil tend to change easily, making it difficult to obtain stable filter performance.

[Purpose of invention]

This invention was made to improve the above-mentioned drawbacks, and the purpose is to provide a plug that prevents electromagnetic induction between the coils, prevents the coil beat phenomenon and magnetostrictive vibration, and has stable filter performance. shall be.

[Summary of the idea]

The plug according to this invention has two built-in coils each covered with an insulating material independently, and the surface of the insulating material on the winding part of each coil is coated with a conductive material to provide electromagnetic shielding. It is something.

[Example of idea]

An embodiment of this invention will be described below with reference to the drawings. In Fig. 2, Chiyoke coil 1
21 is a conductive wire 111 around a cylindrical magnetic body 101.
One end of the conductive wire is connected to the terminal portion 141 of the electrode blade 131, and the other end is connected to one of the lead wires 151 of the cord 15. Similarly, the chiyoke coil 122 is constituted by the magnetic body 102 and the conducting wire 112, and is connected to the terminal portion 142 of the electrode blade 132 and the lead wire 152 of the cord 15, respectively. In this way, the electrode blade 131,1
32 terminal portions 141, 142, chiyoke coils 121, 122, and lead wire 15 of the cord 15.
1 and 152 are separately molded using, for example, a thermoplastic insulating member and integrally formed to form insulating coverings 191 and 192. Only the outer peripheries of these two insulation coverings 191 and 192 corresponding to the portions where the respective cable coils 121 and 122 are present are coated with aluminum foil or coated with conductive paint to form a shield. 20
1,202 is formed. The insulating coverings 191, 192 configured in this way are connected to the electrode blades 131, 1
The plug body 18 is integrally molded using a mold using a thermoplastic insulating member, for example, with the tip of the plug body 32 projecting to the outside. At this time, the covering member of the cord 15 is surrounded and fixed by the insulating member constituting the plug body 18, and even if an external force is applied to the cord 15 during use, the lead wire 15
1,152 received no damage.

Due to the action of the shield parts 201 and 202, the two yoke coils 121 and 12 during use are
Electromagnetic interaction between the two is suppressed. As a result, it becomes possible to arrange the two York coils 121 and 122 close to each other, and the plug body can be made smaller.

Note that to form the insulating coverings 191 and 192, it is also possible to use an insulating cylindrical holder, a heat-shrinkable tube, or the like.

FIG. 3 shows another embodiment of this invention. Basically, the structure is almost the same as that shown in the embodiment shown in FIG. 2 above. Shield parts 201 and 202 formed around the two insulating sheaths 191 and 192, respectively, are led out of the plug body 18 by a lead wire 21 and connected to a ground terminal 22. In this way, the shield part 201,
By grounding 202, it is intended to increase the shielding effect.

[Effect of idea]

As described above, by using the plug according to this invention, it is possible to suppress the occurrence of the beat phenomenon of the chiyok coil and the increase in magnetostrictive vibration, and the change in the electrical characteristics of the chiyok coil is also less likely to occur.
Stable filter performance can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view illustrating the structure of a conventional plug, FIG. 2 is a plan view illustrating the structure of a plug according to this invention, and FIG. 3 is another embodiment of a plug according to this invention. FIG. 101,102...magnetic material, 111,112...
...Conductor wire, 121, 122...Chiyoke coil, 1
31,132... Electrode blade, 15... Cord, 15
1,152...Leader wire, 18...Plug body, 1
91, 192... Insulating covering, 201, 202...
...Shield part, 21...Lead wire, 22...Earth terminal.

Claims (1)

[Scope of utility model registration request] An electrode blade, a chiyoke coil with one end of the winding connected to the electrode blade and the other end connected to the lead wire of the power cord, an insulating sheath provided to cover the chiyoke coil, and the insulating sheath. An insertion plug characterized in that it comprises a shield means having a shield portion provided so as to cover an outer circumferential surface corresponding to the winding.