JPH05251267A - Composite electronic component - Google Patents

Abstract

PURPOSE:To enable a capacitor to be formed into a non-inductive structure low in impedance and enhanced in noise attenuation characteristics by a method wherein the lateral edge of a second electrode foil is made to protrude from the winding edge of a dielectric film, and the second electrode foil and the dielectric film are connected in common into one piece. CONSTITUTION:A wide electrode foil 2, connected to a lead terminal 41, a dielectric film 31 narrower than the electrode foil 21, an electrode foil 22 connected to lead terminals 42 and 43, and a dielectric film 32 are successively wound in multilayer. The wide part 21a of the electrode foil 21 is made to protrude from a winding terminal 1a in a direction opposite to a lead terminal lead-out direction. The wound body concerned is pressed as heated to enable the wide part 21a of the electrode foil 21 which protrudes from the winding terminal 1a to come into close contact with the terminal 1a, whereby the multilayered and wound electrode foil 21 is connected in common with the wide part 21a. By this setup, a capacitor as a composite electronic component, can be set low in impedance and display an excellent noise eliminating performance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite electronic component in which a capacitor and a coil are integrally formed, and more particularly to a composite electronic component capable of maintaining a low impedance by using a non-inductive structure for the capacitor.

[0002]

2. Description of the Related Art Conventionally, it has been applied to electric and electronic devices,
A noise filter is used to remove electrical noise radiated from electric / electronic devices. Of these noise filters, the one that is used most often is a noise filter that has a structure in which one end of each of a capacitor and a coil is commonly connected. In addition to being connected, the capacitor is connected between the line and ground. As a result, the high frequency noise applied to the line is removed by being shielded by the coil and bypassing the capacitor to the ground side.

Even in such a useful noise filter, a small-sized composite electronic component in which a capacitor and a coil are integrated has begun to appear due to the influence of recent lightening and downsizing of electric and electronic equipment. As shown in FIG. 3, this composite electronic component 11 has lead terminals 13 ₁ arranged at appropriate positions on _one of the electrode foils 12 ₁ and 12 _{2 made} of metal such as aluminum or tin. , The other electrode foil 12 ₂
The lead terminals 13 ₂ and 13 ₃ are arranged near one end, which is the beginning of winding, and the other end, which is the end of winding, and dielectric films 14 ₁ and 14 ₂ made of a synthetic resin such as polyester, polypropylene, or polyethylene are provided. , The electrode foils 12 ₁ and 12 ₂ alternately from the inside to the electrode foil 12 ₁ , the dielectric film 14 ₁ , the electrode foil 12 ₂ and the dielectric film 14
_It is laminated in the order of ₂ and wound as shown in FIG.

In the composite electronic component 11, since the electrode foil 12 ₂ is wound, the lead terminals 13 ₂ and 13
Which has a function as a coil inductance occurs between the _3, electrode foil 1 through the dielectric film 14 ₁
2 ₁ , 12 ₂ lead terminals 13 ₁ , 13 ₂ (or 1
Between 3 ₃ ), an electric capacity is generated in the same manner as a normal winding type capacitor, and it has a function as a capacitor.
As a result, the filter circuit, which has been conventionally composed of at least one capacitor and one coil, can be made into a shape substantially equivalent to that of one winding type capacitor, so that a conventional filter can be mounted. Even a small device, which was difficult, can be mounted very easily.

[0005]

However, in the above-mentioned conventional composite electronic component 11, in addition to the electrode foil 12 ₂ having a function as a coil, the electrode foil 12 ₁ having a function as a capacitor is also wound. since it was, the electrode foils 12 _1, 12 ₂ of the lead terminals 13 _1, 13 ₂ (or 13
₃ ) There was unnecessary inductance between the two.

The composite electronic component 11 as described above is mounted on a device, and the lead terminal 13 _{1 is connected} to the ground side, the lead terminal 13 ₂ ,
When 13 ₃ is connected to the line side, the ground side lead terminal 13 ₁ and the line side lead terminal 13 ₂ (or 13
Due to the inductance of the coil component between ₃ ) and, the impedance between the line and ground becomes high, and it becomes difficult for noise to flow to the ground side, so the noise removal capability of the noise filter is poor.

The present invention has been devised in view of the above-mentioned points, and in a composite electronic component in which a capacitor and a coil are integrally formed, the capacitor can be extremely easily formed as a non-inductive structure to maintain a low impedance and to reduce noise. The purpose is to realize a composite electronic component with improved removal capability.

[0008]

In order to achieve the above-mentioned object, the composite electronic component of the present invention comprises a first lead terminal and a second lead terminal.
And a second electrode foil to which the third lead terminal is connected,
In the composite component, which is laminated and wound via a dielectric film, wherein the first electrode foil has an inductance and the first electrode foil and the second electrode foil have an electric capacity, the second component It is characterized in that the side edge of the electrode foil is projected from the winding end surface of the dielectric film and integrally connected in common.

[0009]

The side edges of the second electrode foil are protruded from the winding end surface of the dielectric film and are integrally connected in common so that the second electrode foil having the spirally wound spiral structure is electrically connected. Since it is short-circuited, the first
The capacitor having the electric capacity between the electrode foil and the second electrode foil has a non-inductive structure.

[0010]

1 is an exploded perspective view of a composite electronic component of the present invention, and FIG. 2 is a schematic perspective view of the composite electronic component of the present invention.

In the figure, 1 is a composite electronic component of the present invention, and 2
₁ , 2 ₂ are electrode foils made of metal such as aluminum or tin, 3
_1, 3 ₂ dielectric film made of polyester, polypropylene, synthetic resins such as polyethylene, 4 ₁ electrode foil 2 ₁
The lead terminals connected to the appropriate positions of 4 _{2 and} the electrode foil 2 ₂
Lead terminal connected to the vicinity of one end as the beginning of the winding, 4 ₃
Is a lead terminal connected to the vicinity of the other end of the winding end of the electrode foil 2 _2.

The electrode foil 2 ₁ is wider than the other electrode foils 2 ₁ and the dielectric films 3 ₁ and 3 ₂ by about 0.5 to ₂ mm, and the electrode foil 2 ₁ and the dielectric film 3 ₁ are arranged from the inside. Electrode foil 2
₂ , when the dielectric film 3 ₂ is laminated and wound in this order,
Electrode foil 2 ₁ in electrode foil 2 ₁ and dielectric films 3 ₁ and 3 ₂
The wide portions 2 ₁ a than to protrude from the wound edge 1a of a direction opposite to that of the lead terminal lead-out direction.

Then, this is heated and pressed, and at this time, the wide portion 2 ₁ a of the electrode foil 2 ₁ protruding from the winding end face ₁ a
The electrode foils 2 _{1 that} are laminated and wound are commonly connected in the wide portion 2 ₁ a by pressing and pressing. As a result, although the electrode foil 2 ₁ is wound in a laminated manner, the wide portions 2 ₁ a are commonly connected and electrically short-circuited, so that the inductance becomes almost zero.

FIG. 5 shows the conventional composite electronic component 11 described above.
3 shows noise attenuation characteristics of the composite electronic component 1 of the present invention.

5 is a graph showing the noise attenuation characteristics of the composite electronic component 1 of the present invention, and 6 is the conventional composite electronic component 1
It is a graph which shows the noise attenuation characteristic of 1. Both composite electronic components have an inductance of about 10,000 pF and an electric capacitance of about 0.5 μF. Comparing these two graphs 5 and 6, in the composite electronic component 1 of the present invention of graph 5, the noise attenuation rate in the frequency band of 35 MHz or higher is larger than the noise attenuation rate of graph 6, and The improvement is clear.

[0016]

As described above in detail, according to the composite electronic component of the present invention, the first electrode foil in which the first lead terminal and the second lead terminal are connected to both ends, and the third electrode foil The second electrode foil to which the lead terminal is connected is laminated and wound with a dielectric film interposed between the first electrode foil and the second electrode foil. In a composite component having an electric capacity, the side electrode of the second electrode foil is protruded from the winding end surface of the dielectric film and integrally connected in common to form a second electrode having a spiral structure of laminated winding. Since the foil is electrically short-circuited, it has no inductance, and the capacitor having the electric capacity between the first electrode foil and the second electrode foil has a non-inductive structure. As a result, the capacitor in the composite electronic component has a low impedance and can exhibit an excellent noise removal capability.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a composite electronic component of the present invention.

FIG. 2 is a schematic perspective view of a composite electronic component of the present invention.

FIG. 3 is an exploded perspective view of a conventional composite electronic component.

FIG. 4 is a schematic perspective view of a conventional composite electronic component.

FIG. 5 is a graph showing noise attenuation characteristics of the composite electronic component.

[Explanation of symbols]

1 composite electronic component 1a wound end face 2 _1, 2 ₂ electrode foil 2 ₁ a wide portion 3 _1, 3 ₂ dielectric film 4 _1, 4 _2, 4 ₃ lead terminal

Claims (1)

[Claims] 1. A dielectric material comprising a first electrode foil having a first lead terminal and a second lead terminal connected to both ends thereof and a second electrode foil having a third lead terminal connected thereto. In the composite component, which is laminated and wound via a film, the first electrode foil has an inductance, and the first electrode foil and the second electrode foil have an electric capacity, the second electrode foil. A composite electronic component, wherein side edges of the dielectric film are projected from a winding end surface of the dielectric film and integrally connected in common.