JPH0922857A - Electronic parts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress noise in wide frequency band from low to high frequency by forming an insulation layer and a conductive layer in order at least on a part of the surface of a coillike conductor. SOLUTION: Since the outer periphery of a coil-like conductor 13 coated with an insulation layer 14 is coated with a conductive layer 15, inductance component is generated at the coil-like part of the conductor 13, and further electrostatic capacity component is generated between the conductor 13 and the conductor layer 15, with the insulation layer 14 in between, so that an LC filter circuit is constituted. Therefore, without using a capacitor of complex configuration, noise in wide area from low to high frequency is suppressed with simple configuration in which no inductor element is added. And, since the outer periphery part of the conductor 13 is surrounded with the conductor layer 15 and a conductive member 16, cold loss is about 40db even when the frequency of high frequency current gets high, thus, occurring of high frequency noise is suppressed almost perfectly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component for removing noise used in electronic equipment, microwave ovens and the like.

[0002]

2. Description of the Related Art As shown in FIG. 9, a conventional capacitor 1 includes a first dielectric film 3 having a first electrode layer 2 and a second dielectric film 5 having a second electrode layer 4.
As shown in FIG. 10, a cylindrical capacitor unit 8 formed by superposing and winding on a cylindrical core 7 made of an insulating material that surrounds the outer peripheral portion of the through terminal 6 and inserted into the core 7. A ring-shaped first metallikon electrode 9 connected to the first electrode layer 2, and inserted into the winding core 7;
Ring-shaped second metallikon electrode 10 connected to the electrode layer 4, the grounding terminal plate 11 inserted into the winding core 7 and soldered to the first metallikon electrode 9, and the penetrating terminal 6
And a current collector plate 12 which is inserted into the second metallikon electrode 10 and soldered to the second metallikon electrode 10. An inductor element (not shown) is connected to this capacitor 1 to provide a wide range of frequencies from low frequency to high frequency. The noise in the band was suppressed.

[0003]

However, in the conventional capacitor 1 as described above, the structure becomes complicated, and since the inductor element is further connected, the manufacturing cost becomes high, and the frequency of the high frequency current becomes high.
There is a problem that the high frequency noise is radiated outward from both ends of the outer periphery of the capacitor unit 8 and the effect of suppressing the high frequency noise is small.

The present invention provides an electronic component capable of suppressing noise in a wide frequency band from a low frequency to a high frequency with a simple structure without adding an inductor element.

[0005]

The electronic component of the present invention is one in which an insulating layer and a conductive layer are sequentially formed on at least a part of the surface of a coil-shaped conductor.

[0006]

With this structure, an inductance component is generated in the coil-shaped portion of the conductor, and a capacitance component is generated between the conductor and the conductive layer via the insulating layer, so that noise can be generated over a wide frequency band. Can be suppressed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings.

The electronic component of the first embodiment of the present invention is shown in FIGS.
As shown in FIG. 4, a wire diameter of 1-2 mm, an outer diameter of 6-8 mm,
Coil-shaped annealed copper wire having a length of 15 to 25 mm, conductor 13 made of aluminum or the like, and polyamide imide having a thickness of 30 to 500 μm covering the surface of the conductor 13, fluororesin and silicon, and pressure resistance and heat resistance The insulating layer 14 is made of a resin having a resin, and the outer peripheral surface of the insulating layer 14 is provided with a silver paste coated or a conductive layer 15 made of zinc, nickel, copper, tin or the like coated by thermal spraying. The conductive layer 15 is inserted and fixed in a cylindrical conductive member 16 made of aluminum, zinc, iron or the like, and is attached to the grounding terminal plate 17 made of aluminum, zinc, iron or the like provided on the conductive member 16. It is electrically connected. Then, the conductor 13, the conductive member 16, and the grounding terminal plate 17
Are molded with an insulating resin 18. With this structure, an electrostatic capacitance is formed between the conductor 13 and the ground terminal plate 17.

Next, the operation of the electronic component will be described. In the first embodiment of the present invention, since the conductive layer 15 is coated on the outer peripheral surface of the coil-shaped conductor 13 coated with the insulating layer 14, an inductance component is generated in the coil-shaped portion of the conductor 13 and insulation is achieved. Conductor 13 and conductive layer 15 through layer 14
An electrostatic capacitance component is generated between and to form an LC filter circuit. Therefore, the electronic component of the present embodiment is different from the conventional one in that it does not use a capacitor having a complicated configuration and has a simple configuration in which an inductor element is not added, and noise in a wide frequency band from a low frequency to a high frequency is generated. Can be suppressed. Further, since the outer peripheral portion of the conductor 13 is surrounded by the conductive layer 15 and the conductive member 16, the cold loss is about 40 dB even when the frequency of the high frequency current is high, and the generation of high frequency noise is almost completely suppressed. can do.

Next, an experimental example confirming the effect of the present invention will be described. In the electronic component (invention product) of the embodiment of the present invention having the configuration shown in FIG. 1, the conductor 13 is an annealed copper wire having a wire diameter of 1.4 mm and having an outer diameter of 5.5 mm and a length of 30 μm, which is coated with polyamide-imide. It is formed into a coil shape having a length of 21 mm, and the outer peripheral surface of the coil is covered with a conductive layer 15 of silver paste, and has a capacitance of about 500 pF.

In order to compare with this, a structure (conventional product) having the structure shown in FIG. 10 in which an inductor element of about 2 μF is connected in series to a conventional capacitor having an electrostatic capacity of about 500 pF was manufactured.

When the noise attenuation of these in cold state was investigated, the results shown in FIG. 5 were obtained. The curve A shows the product of the present invention, and the curve B shows the conventional product.

As is apparent from FIG. 5, the product of the present invention is 3
In the cold state of the wide band of 0 KHz to 3 GHz,
From the conventional product, it can be seen that the cold loss becomes flat at about 40 dB over the entire area, and the LC filter circuit capable of suppressing noise is configured.

FIG. 6 shows a second embodiment of the present invention. In this case, the first embodiment differs from the first embodiment in that the coil-shaped inner diameter portion of the conductor 13 has a rod-shaped ferrite core 1 as a high-frequency absorbing member.
The difference is that 9 is provided.

According to the second embodiment, by providing the ferrite core 19, noise can be further suppressed.

FIG. 7 shows a third embodiment of the present invention. In this case, the conductive layer 15 differs from the first embodiment in that the conductive layer 15 covers the conductive layer 15 in the coil length direction and the non-coating. The difference is that the portions 21 are repeated to form stripes.

According to the third embodiment, the covered portion 20 and the uncovered portion 21 of the conductive layer 15 are arranged in the coil length direction of the conductor 13.
Since it is formed repeatedly, an inductance component is generated in the non-covered portion 21 and an inductance component and a capacitance component are generated in the coated portion 20 to form the LC filter circuit. The coil length can be further shortened. Also, to shorten the length, the covering portion 20
The relationship between the uncovered part 21 and the uncovered part 21 is such that the width X of the covered part 20 is larger than the width Y of the uncovered part 21, preferably the width X of the covered part 20.
Is preferably about twice the width Y of the uncovered portion 21.

In the first to third embodiments described above, the case where the conductive layer 15 is provided on the outer peripheral surface of the coil-shaped conductor 13 covered with the insulating layer 14 has been described, but the coil-shaped portion of the conductor 13 is described. It may be provided on the outer peripheral surface or the inner peripheral surface. Also,
Although the coil-shaped portion of the conductor 13 is described as being circular, it may be elliptical, angular, spiral, or the like. Further, in the third embodiment, the covering portion 20 and the non-covering portion 21 of the conductive layer 15 are
Although the case where the coil is repeatedly formed in the coil length direction has been described, it may be repeatedly formed in the radial direction or spirally formed on the coil-shaped outer peripheral surface.

FIG. 8 shows a fourth embodiment of the present invention. In this case, a pair of conductors 13a and 13b whose outer peripheral portions are successively covered with an insulating layer 14 and a conductive layer 15 are ring-shaped high frequency absorbing members. Each of the conductors 13a and 13b is wound around a coil 19a in the form of a coil, and the outer peripheral circular portion of the conductive layer 15 is fixed by a conductive member 16a made of a ring-shaped copper wire. The conductive layer 15 of the conductors 13a and 13b is electrically connected to the ring-shaped conductive member 16a and grounded. As a result, an inductance component is generated in the coil-shaped portions of the conductors 13a and 13b, and a capacitance component is generated between the conductors 13a and 13b and the conductive layer 15 via the insulating layer 14 to form an LC filter circuit. be able to.

According to the fourth embodiment, since the conductors 13a and 13b are wound around the ring-shaped high frequency absorbing member 19a in a coil shape, a current containing a noise component flowing through the conductors 13a and 13b is passed. Then, a magnetic flux is generated in the high frequency absorbing member 19a of the conductor 13a and the conductor 13b in a direction opposite to the current containing the noise component, and the magnetic flux cancels the noise component of the current flowing in the conductors 13a and 13b. The effect of suppressing high frequency noise can be improved.

In the fourth embodiment, the outer circumferential circle of the conductive layer 15 of the conductors 13a and 13b wound in a ring shape is
Although the case where the conductive member 16a is fixed by the conductive member 16a has been described, the conductive member 16a is formed by surrounding the conductors 13a and 13b and the high frequency absorbing member 19a, or a cylindrical conductive member as shown in FIG. The member is formed in a ring shape, and the conductors 13a and 13b and the high frequency absorbing member 1 are also provided.
9a is changed to a conductive member surrounded by a tubular portion, and the conductive members fix the outer peripheral portions of the conductors 13a and 13b to electrically connect the conductive member and the conductive layer 15. Good. With this configuration, the high frequency absorbing member 19a
Since the conductors 13a and 13b are surrounded by the conductive member, the generation of high frequency noise can be suppressed almost completely even if the frequency of the high frequency current is increased.

[0022]

As described above, the present invention has a structure in which an insulating layer and a conductive layer are sequentially formed on at least a part of the surface of a coil-shaped conductor, thereby simplifying the structure of the LC filter circuit. To reduce costs,
Moreover, it is possible to obtain a capacitor capable of suppressing noise in a wide frequency band.

[Brief description of drawings]

FIG. 1 is a front sectional view of a capacitor which is a first embodiment of the present invention.

[Fig. 2] Left side view of the capacitor

FIG. 3 is a configuration diagram of a main part of the capacitor.

FIG. 4 is a cross-sectional view taken along the line A-A ′ of the main part configuration diagram of the capacitor.

FIG. 5 is a noise attenuation characteristic diagram of the product of the present invention and the conventional product.

FIG. 6 is a front sectional view of a main part of a capacitor which is a second embodiment of the present invention.

FIG. 7 is a front sectional view showing an essential part of a capacitor which is a third embodiment of the present invention.

FIG. 8 is a front sectional view of a main part of a capacitor which is a fourth embodiment of the present invention.

FIG. 9 is a perspective view of a main part of a capacitor unit of a conventional capacitor.

FIG. 10 is a front sectional view of the capacitor.

[Explanation of symbols]

 13 conductor 14 insulating layer 15 conductive layer

Claims (8)

[Claims] 1. An electronic component, wherein an insulating layer and a conductive layer are sequentially formed on at least a part of the surface of a coil-shaped conductor. 2. The electronic component according to claim 1, wherein the conductive layer is coated in a stripe shape. 3. A conductive layer is formed in a lengthwise direction of a coil-shaped conductor, and a relationship between a covered portion and an uncovered portion of the conductive layer is such that the covered portion width is larger than the uncovered portion width. The electronic component according to claim 2. 4. The electronic component according to claim 1, wherein the insulating layer has a thickness of 30 to 500 μm. 5. The electronic component according to claim 1, wherein the conductive layer is inserted and fixed in a cylindrical conductive member, and the conductive member is grounded. 6. The electronic component according to claim 1, wherein a high-frequency absorbing member is provided on a coil-shaped inner diameter portion of the conductor. 7. The electronic component according to claim 6, wherein the high frequency absorbing member has a ring shape. 8. The electronic component according to claim 7, wherein the coil shape of the high frequency absorbing member and the conductor is surrounded by a conductive member, and the conductive member is grounded.