JPH08111602A - Multilayer filter - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide a small size and high performance multilayer filter without using a material having a large dielectric constant. [Structure] The ceramic sheets 1, 3, 5, 9, 11 are laminated to form a filter body 15, and the ceramic sheet 5
Then, a strip line 18 including a U-shaped electrode 16 having a U-shape having a recess and a strip electrode 17 protruding from the recess of the U-shape electrode 16 was provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated filter used for communication equipment and the like.

[0002]

2. Description of the Related Art A conventional technique will be described below with reference to the drawings.

FIG. 3 is an exploded perspective view of a conventional laminated filter. As shown in FIG. 3, the multilayer filter includes ceramic sheets 1, 3, 5, 9, 1 made of a plurality of dielectrics.
It is composed of a filter body 15 formed by laminating 1 pieces. The lower shield electrode 2 is provided on the ceramic sheet 1, the interstage coupling electrode 6, the input / output coupling electrode 7 and the frequency adjusting electrode 8 which are internal electrodes are provided on the ceramic sheet 3, and the strip line 4 is provided on the ceramic sheet 5. An upper shield electrode 10 is provided on each of the ceramic sheets 9.
Further, the lower shield electrode 2, the upper shield electrode 10, the strip electrode 4 of the strip line 4, the frequency adjusting electrode 8
Is electrically connected to the earth electrodes 12 and 14 which are external electrodes provided on the outer peripheral surface of the filter body 15. further,
The input / output coupling electrode 7, the lower shield electrode 2, and the upper shield electrode 10 are electrically connected to the input / output electrode 13, which is an external electrode provided on the outer peripheral surface of the filter body 15.

[0004]

In the above structure, generally, when a certain frequency band is to be obtained, the frequency band is uniquely determined by the length of the strip electrode 17 of the strip line 4, so that the size of the ceramic sheet 5 is large. The problem is that the length of the strip line 4 affects the laminated filter, and the laminated filter cannot be downsized.

The present invention solves the above problems, and an object of the present invention is to provide a multilayer filter which is downsized.

The present invention solves the above problems, and an object of the present invention is to provide a small-sized and high-performance laminated filter.

[0007]

In order to achieve the above object, the present invention provides a filter body formed by laminating a plurality of ceramic sheets, and a strip line and an internal electrode provided between the ceramic sheets of the filter body. An external electrode that is provided on the outer peripheral surface of the filter body and that is electrically connected to the strip line and the internal electrode, the strip line having a U-shaped electrode having a recess, and The strip-shaped electrode protrudes from the concave portion of the U-shaped electrode, and the strip-shaped electrode is electrically connected to the external electrode.

[0008]

According to the above structure, since the strip-shaped strip-shaped electrode projects from the recess of the U-shaped electrode, the ceramic sheet can be made small without changing the length of the strip line, and as a result, the laminated structure can be obtained. The mold filter can also be downsized.

[0009]

1 is an exploded perspective view of a laminated filter according to the present invention, and FIG. 2 is an enlarged view of a strip line of the laminated filter.

A filter body 15 is formed by laminating ceramic sheets 1, 3, 5, 9, and 11. The ceramic sheet 1 had a lower shield electrode 2, the ceramic sheet 3 had an interstage coupling electrode 6, an input / output coupling electrode 7 and a frequency adjusting electrode 8 as internal electrodes, and the ceramic sheet 5 had a recess. U-shaped electrode 16 having a U-shape
And the strip line 18 consisting of the strip-shaped electrode 17 protruding from the concave portion of the U-shaped electrode 16, the ceramic sheet 9
An upper shield electrode 10 is provided on each of the above. Further, the lower shield electrode 2, the upper shield electrode 10, the strip line 18, and the frequency adjusting electrode 8 are ground electrodes 12, which are external electrodes provided on the outer peripheral surface of the filter body 15.
It is electrically connected to 14.

Further, the input / output coupling electrode 7, the lower shield electrode 2 and the upper shield electrode 10 are electrically connected to the input / output electrode 13 which is an external electrode provided on the outer peripheral surface of the filter body 15.

According to the multilayer filter having the above structure, since the strip electrode 17 of the strip line 18 projects from the concave portion of the U-shaped electrode 16, the ceramic sheet 5 can be made small without changing the length of the strip line. can do. As a result, the size of the ceramic sheet 5 on which the strip lines 18 are laminated can be reduced, and the multilayer filter itself can be reduced accordingly.

[0013]

As described above, according to the present invention, a strip line composed of a U-shaped electrode having a recess and a strip electrode connected to the recess of the U-shaped electrode is provided between a plurality of ceramic sheets. Since the configuration is provided, it is possible to provide a small-sized and highly practical multilayer filter.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a laminated filter according to the present invention.

FIG. 2 is an enlarged plan view of a strip line of the same multilayer filter.

FIG. 3 is an exploded perspective view of a conventional laminated filter

[Explanation of symbols]

 1 Ceramic Sheet 2 Lower Shield Electrode 3 Ceramic Sheet 5 Ceramic Sheet 6 Inter-Stage Coupling Electrode 7 Input / Output Coupling Electrode 8 Frequency Adjustment Electrode 9 Ceramic Sheet 10 Upper Shield Electrode 11 Ceramic Sheet 12 Earth Input Electrode 13 Input / Output Electrode 14 Earth Electrode 15 Filter body 16 U-shaped electrode 17 Strip-shaped electrode 18 Strip line

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Banno 55-12 Oaza, Ozumi, Tanabe-cho, Tsuzuki-gun, Kyoto Prefecture Matsushita Nitto Electric Co., Ltd. (72) Hiroshi Shigemura, Tanabe-cho, Tsuji-gun, Kyoto Prefecture Sumikojihama 55-12 Matsushita Nitto Electric Co., Ltd.

Claims (1)

[Claims] 1. A filter body formed by laminating a plurality of ceramic sheets, a strip line and an internal electrode provided between the ceramic sheets of the filter body, an outer peripheral surface of the filter body, and the strip line and An external electrode electrically connected to the internal electrode is provided, and the strip line includes a U-shaped electrode having a U-shape having a recess, and a strip electrode protruding from the recess of the U-shape electrode, A laminated filter in which the strip electrode is electrically connected to the external electrode.