JPH021844Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a shielded inductor coated with a magnetic material such as ferrite.

Conventionally, as shown in the first diagram, this type of inductor has a cylindrical core b with a flange, which has a lead wire a led out in the axial direction from the end, and a winding c is applied to the core b. accommodated in the hollow part of the shaped core d,
It is known that the gap between the core d and the cylindrical core b is filled with a synthetic resin e for the purpose of moisture-proofing the windings and fixing the cylindrical core b, but this method has the following disadvantages. That is, since the cylindrical core d is long and tends to be distorted during molding, the inner diameter thereof is molded to a size with a margin larger than that of the cylindrical core b. Therefore, a gap is likely to be formed between the outer periphery of the cylindrical core b and the inner periphery of the cylindrical core d, making it impossible to provide complete shielding and causing variations in inductance.
Further, when filling the synthetic resin e, the resin is difficult to inject and easily flows after injection, making manufacturing difficult.

The object of the present invention is to provide a shielded inductor free from the above-mentioned disadvantages, and is a cylindrical core having a winding 1 on the circumferential surface and a lead wire 2 led out in the axial direction from the end. 3 and two pot cores 5, 5 having a through hole 4 for the lead wire 2 on the bottom surface, the open ends of the two pot cores 5, 5 are joined to each other, and the cylindrical core 3 is housed inside. At the same time, the lead wire 2 is inserted into the through hole 4.

FIG. 2 shows a cross-sectional view of one embodiment of the present invention.

In the figure, a flanged core is used as the cylindrical core 3 of the inductor provided with the winding 1, two pot cores 5, 5 are used as the shielding core, and the base of the lead wire 2 is attached to the bottom of the pot core 5. A recess 7 is formed to accommodate the terminal 6 of the connected winding 1.
The pot cores 5, 5 are sized so that when the opening lids are fixed together, the flange of the cylindrical core 3 housed inside comes into contact with the bottom surface. Further, a cylindrical core 3 is located approximately at the center of the bottom surface of the pot cores 5, 5.
A through hole 4 is provided for the lead wire 2 led out in the axial direction from the end of the pot core 5, the lead wire 2 is inserted into the through hole 4, and the cylindrical core 3 is disposed approximately in the center of the internal space of the two pot cores 5, 5. It has been set. Further, the joint between the pot cores 5, 5 and the pot core lead-out portion of the lead 2 were filled with resin and sealed.

In the figure, reference numeral 8 denotes an adhesive that bonds the two pot cores 5, 5 to each other on the inside thereof, and also bonds the pot cores 5, 5 and the inductor. FIG. 3 shows a cross-sectional view of another embodiment of the invention. In the figure, a flangeless drum core was used as the cylindrical core 3 of the inductor to which the winding 1 was applied.

The two pot cores 5, 5 that cover the drum core 3 are fixed to each other by coating their entire outer periphery with a resin paint 9, and metal caps 10, 10 are fitted to each end of the pot cores 5, 5, and the metal caps 10 are attached to the metal caps 10. The end of the lead wire 2 inserted through the hole was soldered. This inductor is suitable for being soldered directly to a printed circuit board as an inductance chip.

It is more convenient to use a heat-shrinkable resin tube instead of the resin paint.

As described above, according to the present invention, since the two pot cores 5, 5, which are short in length and have a bottom plate at one end, are used as shielding cores, there is less shape distortion and variation in inductance compared to conventional ones. Magnetic leakage can be completely blocked. In addition, since the lead wire 2 is inserted through the through hole 4 provided at the bottom of the pot cores 5, 5, the positioning of the cylindrical core 3 with respect to the pot core 5 is easy, and there is little variation in inductance. By sealing the joint portion and the lead wire penetration portion of the pot core 5, the purpose of moisture proofing can be achieved, and this work can be done quickly and easily.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional shielded inductor, and FIGS. 2 and 3 are sectional views of an embodiment of the present invention, respectively. 1... Winding wire, 2... Lead wire, 3... Cylindrical core, 4... Through hole, 5... Pot core.

Claims (1)

[Scope of utility model registration request] A cylindrical core 3 having a winding 1 on the circumferential surface and a lead wire 2 led out in the axial direction from the end, and two pot cores 5, 5 having a through hole 4 for the lead wire 2 on the bottom surface. The two pot cores 5,
5 are joined together at their open ends, the cylindrical core 3 is accommodated therein, and the lead wire 2 thereof is inserted through the through hole 4.