JPH0241949Y2 - - Google Patents
Info
- Publication number
- JPH0241949Y2 JPH0241949Y2 JP9235684U JP9235684U JPH0241949Y2 JP H0241949 Y2 JPH0241949 Y2 JP H0241949Y2 JP 9235684 U JP9235684 U JP 9235684U JP 9235684 U JP9235684 U JP 9235684U JP H0241949 Y2 JPH0241949 Y2 JP H0241949Y2
- Authority
- JP
- Japan
- Prior art keywords
- piezoelectric ceramic
- outer electrode
- electrode
- spurious
- ceramic vibrator
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000000919 ceramic Substances 0.000 claims description 43
- 230000002093 peripheral effect Effects 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 description 8
- 230000000694 effects Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 230000001629 suppression Effects 0.000 description 4
- 238000007796 conventional method Methods 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000007650 screen-printing Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
Description
【考案の詳細な説明】
産業上の利用分野
本考案は、例えば455KHzのAMバンドの圧電
フイルタとして使用するのに好適な圧電磁器振動
子に関する。[Detailed Description of the Invention] Industrial Application Field The present invention relates to a piezoelectric ceramic vibrator suitable for use as a piezoelectric filter in the AM band of 455 KHz, for example.
従来技術
この種の圧電磁器振動子としては、例えば第１
図及び第２図に示すように、平行四辺形の平板状
に形成された圧電磁器素体１の一面上に、その外
周縁に沿つて外側電極２をリング状に設けると共
に、この外側電極２の内側にギヤツプg1を隔て
て、内側電極３をドツト状に設け、更に圧電磁器
素体１の他面の略全面に内側電極３及び外側電極
２に共通に対向する共通電極４を設けた角板型の
ものが知られている。Prior Art As this type of piezoelectric ceramic vibrator, for example, the first
As shown in the figures and FIG. 2, an outer electrode 2 is provided in a ring shape along the outer periphery on one surface of a piezoelectric ceramic body 1 formed in the shape of a parallelogram plate. An inner electrode 3 is provided in a dot shape on the inside of the piezoelectric ceramic body 1 with a gap g 1 in between, and a common electrode 4 is provided on substantially the entire other surface of the piezoelectric ceramic body 1 to commonly face the inner electrode 3 and the outer electrode 2. A square plate type is known.
しかし、第１図及び第２図に示した圧電磁器振
動子の場合、基本共振周波数に対する高次高調波
のスプリアスが非常に大きく、圧電フイルタとし
て使用することが困難である。高調波スプリアス
抑圧を目的とした従来技術としては、、例えば特
公昭46−18457号、特開昭55−143815、或いは特
開昭55−143816号等を挙げることができる。これ
らの従来技術の内、特公昭46−18457号は外側電
極と内側電極との外辺比を特定の値に設定するこ
とにより、また特開昭55−143815号及び特開昭55
−143816号は圧電磁器素体の長辺と短辺の辺比及
び二辺のなす頂角の角度を特定の値に設定するこ
とにより、高調波スプリアスを低減させるもので
ある。 However, in the case of the piezoelectric ceramic vibrator shown in FIGS. 1 and 2, spurious high-order harmonics relative to the fundamental resonance frequency are extremely large, making it difficult to use as a piezoelectric filter. Examples of conventional techniques aimed at suppressing harmonic spurious waves include Japanese Patent Publication No. 46-18457, Japanese Patent Application Laid-open No. 143815-1983, and Japanese Patent Application Laid-Open No. 143816-1984. Among these conventional techniques, Japanese Patent Publication No. 46-18457 sets the outer edge ratio of the outer electrode and the inner electrode to a specific value, and
No. 143816 reduces harmonic spurious by setting the ratio of the long side to the short side of the piezoelectric ceramic body and the apex angle formed by the two sides to specific values.
従来技術の欠点
しかしながら、特公昭46−18457号は或る特定
の高調波スプリアス、例えば基本共振周波数
455KHzとした場合、その３次高調波に略等しい
1.2MHz付近に発生するスプリアスを抑圧できる
だけで、他の高調波のスプリアスをを抑圧するこ
とはできない。Disadvantages of the prior art However, Japanese Patent Publication No. 18457/1986 has a certain harmonic spurious, e.g. fundamental resonant frequency.
When set to 455KHz, it is approximately equal to its third harmonic.
It can only suppress the spurious that occurs around 1.2MHz, but it cannot suppress the spurious of other harmonics.
また、特開昭55−143815号及び特開昭55−
143816号は特公昭46−18457号の上記欠点を解決
することを狙つたものであるが、圧電磁器素体を
製造するに当つて、長辺及び短辺の辺比を特定の
寸法比に設定し、更に頂角の角度を特定の値に設
定する必要があるため、圧電磁器素体の製造が面
倒であること、辺比及び角度を要求値に正確にセ
ツトすることが容易ではなく、所期のスプリアス
抑圧効果を得ることが困難であること、圧電磁器
素体の材料無駄を生じ易いこと等の難点がある。 Also, JP-A-55-143815 and JP-A-55-
No. 143816 aims to solve the above-mentioned shortcomings of Japanese Patent Publication No. 46-18457, but when manufacturing a piezoelectric ceramic body, the side ratio of the long side and short side is set to a specific dimensional ratio. However, since it is necessary to set the apex angle to a specific value, manufacturing the piezoelectric ceramic body is troublesome, and it is not easy to accurately set the side ratio and angle to the required values, and However, there are disadvantages such as difficulty in obtaining the desired spurious suppression effect and the tendency to waste material in the piezoelectric ceramic body.
本考案の目的
本考案は上述する従来の問題点を解決し、複数
種の高調波スプリアスを確実に抑圧することがで
き、しかも、製造が容易で、製造上の特性バラツ
キ等を生じることなく、所期の高調波スプリアス
抑圧作用を確実に引出し得る圧電磁器振動子を提
供することを目的とする。Purpose of the present invention The present invention solves the above-mentioned conventional problems, can reliably suppress multiple types of harmonic spurious, is easy to manufacture, and does not cause variations in manufacturing characteristics. It is an object of the present invention to provide a piezoelectric ceramic vibrator that can reliably bring out the desired harmonic spurious suppression effect.
本考案の構成
上記目的を達成するため、本考案は、平行四辺
形の外形を有して平板状に形成された圧電磁器素
体の一面上に、その外周縁に沿つて外側電極を設
けると共に、この外側電極の内側にギヤツプを隔
てて内側電極を設け、前記圧電磁器素体の他面側
に前記内側電極及び外側電極に共通に対向する共
通電極を設けた圧電磁器振動子において、前記圧
電磁器素体の少なくとも一つの隅部に、前記外側
電極の存在しない領域を有することを特徴とす
る。Structure of the present invention In order to achieve the above object, the present invention provides an outer electrode along the outer periphery on one surface of a piezoelectric ceramic element having a parallelogram outer shape and formed into a flat plate. In the piezoelectric ceramic vibrator, an inner electrode is provided inside the outer electrode with a gap therebetween, and a common electrode is provided on the other surface side of the piezoelectric ceramic body, which commonly faces the inner electrode and the outer electrode. It is characterized in that the ceramic body has a region in which the outer electrode does not exist in at least one corner.
実施例
第３図は本考案に係る圧電磁器振動子の実施例
１の平面図、第４図は第３図B1−B1線上におけ
る断面図である。図において、第１図及び第２図
と同一の参照符号は同一性ある構成部分を示す。
本考案においては、平行四辺形状の外形を有して
平板状に形成された圧電磁器素体１の一面上の外
周縁に沿つて、外側電極２をリング状に設ける場
合に、圧電磁器素体１の四隅部イ〜ニの内の少な
くとも一つの隅部イに、外側電極２の存在しない
領域５を設ける。この実施例１では、領域５は隅
部イの頂角６を構成する二辺７，８からギヤツプ
の方向に向つて、外側電極２を分断するように形
成されている。このような領域５は、内側電極３
及び外側電極２を例えばスクリーン印刷等の手段
によつて塗布形成する場合のパターンにより同時
に形成できる。Embodiment FIG. 3 is a plan view of Embodiment 1 of the piezoelectric ceramic vibrator according to the present invention, and FIG. 4 is a sectional view taken along line B 1 -B 1 in FIG. In the figures, the same reference numerals as in FIGS. 1 and 2 indicate identical components.
In the present invention, when the outer electrode 2 is provided in a ring shape along the outer periphery on one surface of the piezoelectric ceramic element 1, which is formed into a flat plate shape and has a parallelogram shape, the piezoelectric ceramic element A region 5 where the outer electrode 2 does not exist is provided in at least one corner A of the four corners A to D of 1. In the first embodiment, the region 5 is formed so as to divide the outer electrode 2 from the two sides 7 and 8 forming the apex angle 6 of the corner A in the direction of the gap. Such a region 5 is the inner electrode 3
and the outer electrode 2 can be formed at the same time according to a pattern used when forming the outer electrode 2 by coating by means such as screen printing.
上述のように、圧電磁器素体１の四隅部イ〜ニ
の少なくとも一隅部イに、外側電極２の存在しな
い領域５を設けると、高調波スプリアスを確実に
抑圧することができることが解つた。例えば、基
本共振周波数をAMバンドの455KHzに選定した
場合には、650KHz，950KHz，1.2MHz付近におけ
る各スプリアスを抑圧できる。第５図は第１図及
び第２図に示した従来の圧電磁器振動子の周波数
−利得特性図、第６図は第３図及び第４図におい
て実施例１として示した圧電磁器振動子の周波数
−利得特性図である。第５図と第６図との比較か
ら明らかなように、基本共振周波数455KHzに対
して、650KHz，950KHz及び1.2MHzの何れの高調
波におけるスプリアス減衰量も、本考案に係る実
施例１の圧電磁器振動子の方が従来例の場合より
大きくなつている。より詳しいデータを挙げる
と、基本共振周波数455KHzに対して、650Kmm2，
950KHz，1.2MHz付近のスプリアス減衰量が、第
１図及び第２図に示す従来例では、それぞれ、−
13.23dB，−9.64dB，−12.05dBであつたが、本考
案の実施例１では、それぞれ、−15.83dB，−
10.04dB，−13.82dBとなり、明らかなスプリアス
改善効果が得られた。 As mentioned above, it has been found that harmonic spurious can be reliably suppressed by providing the region 5 where the outer electrode 2 does not exist in at least one corner A of the four corners A to D of the piezoelectric ceramic body 1. For example, if the fundamental resonant frequency is selected to be 455 KHz in the AM band, each spurious at around 650 KHz, 950 KHz, and 1.2 MHz can be suppressed. FIG. 5 is a frequency-gain characteristic diagram of the conventional piezoelectric ceramic vibrator shown in FIGS. 1 and 2, and FIG. 6 is a diagram of the piezoelectric ceramic vibrator shown as Example 1 in FIGS. 3 and 4. It is a frequency-gain characteristic diagram. As is clear from the comparison between FIG. 5 and FIG. 6, the amount of spurious attenuation at any of the harmonics of 650 KHz, 950 KHz and 1.2 MHz with respect to the fundamental resonance frequency of 455 KHz is The magnetic vibrator is larger than the conventional example. To give more detailed data, the fundamental resonance frequency is 455KHz, 650Kmm 2 ,
In the conventional examples shown in Figures 1 and 2, the amount of spurious attenuation near 950KHz and 1.2MHz is -
13.23dB, -9.64dB, -12.05dB, but in Example 1 of the present invention, -15.83dB, -12.05dB, respectively.
10.04dB, -13.82dB, and a clear spurious improvement effect was obtained.
本考案の圧電磁器振動子の具体的構造に関して
は、上記実施例１の他にも、種々の実施態様が考
えられる。その代表例を第７図〜第１０図に示し
てある。まず、第７図の実施例では、同一辺７を
含む２つの隅部イ，ロに外側電極２の存在しない
領域５１，５２をそれぞれ形成してある。各領域
５１，５２は外側電極２を分断するように設けら
れる。領域５１，５２によつて分断された外側電
極２−２間は電気的に導通接続させて、同電位に
保つ。これを実施例２とする。 Regarding the specific structure of the piezoelectric ceramic vibrator of the present invention, various embodiments can be considered in addition to the first embodiment described above. Typical examples thereof are shown in FIGS. 7 to 10. First, in the embodiment shown in FIG. 7, regions 51 and 52 where the outer electrode 2 does not exist are formed at two corners A and B including the same side 7, respectively. Each region 51, 52 is provided so as to divide the outer electrode 2. The outer electrodes 2-2 separated by the regions 51 and 52 are electrically connected and kept at the same potential. This is referred to as Example 2.
次に第８図の実施例では、四つの隅部イ〜ニの
それぞれに外側電極２の存在しない領域５１〜５
４を設けた例を示している。各領域５１〜５４は
外側電極２の内部に形成さる。従つて、外側電極
２は前記領域５１〜５４によつて分断されること
がなく、電気的に同電位となつている。これを実
施例３とする。 Next, in the embodiment shown in FIG.
4 is shown. Each region 51 to 54 is formed inside the outer electrode 2. Therefore, the outer electrode 2 is not divided by the regions 51 to 54 and is electrically at the same potential. This is referred to as Example 3.
また第９図では、一つの隅部イにおいて、頂角
６を挟む辺７及び８に平行する方向にギヤツプg1
を延長して外側電極２の存在しない領域５１，５
２を形成してある。 In addition, in FIG. 9, at one corner A, there is a gap g 1 in a direction parallel to sides 7 and 8 that sandwich the apex angle 6.
is extended to form regions 51, 5 where the outer electrode 2 does not exist.
2 is formed.
これを実施例４とする。 This is referred to as Example 4.
更に第１０図の実施例では、対向する頂各部分
イ，ハに外側電極２の存在しない領域５１，５２
を設けてある。領域５１，５２の両側の外側電極
２−２間は電気的に導通接続させて同電位に保
つ。これを実施例５とする。 Furthermore, in the embodiment shown in FIG. 10, regions 51 and 52 where the outer electrode 2 is not present are provided at each of the opposing top portions A and C.
is provided. The outer electrodes 2-2 on both sides of the regions 51 and 52 are electrically connected and kept at the same potential. This is referred to as Example 5.
次に、第１図及び第２図に示した従来例と、上
記実施例１〜５に示した圧電磁器振動子につい
て、650KHz，950KHz，1.2MHzの各高調波におけ
るスプリアス減衰量dBを下に示す。 Next, for the conventional example shown in Fig. 1 and Fig. 2 and the piezoelectric ceramic vibrator shown in Examples 1 to 5 above, the spurious attenuation amount dB at each harmonic of 650 KHz, 950 KHz, and 1.2 MHz is determined below. show.
スプリアス抑圧量dB
650KHz 950KHz 1.2MHz
従来例 13.23 9.64 12.05
実施例１ 15.83 10.40 12.58
実施例２ 17.43 11.34 13.56
実施例３ 14.76 11.30 12.26
実施例４ 16.25 9.26 11.90
実施例５ 15.28 12.02 13.82
上記データから明らかなように、何れの実施１
〜５の場合にも、高調波に対するスプリアス改善
効果が得られる。なお、実施例４においては、
950KHz及び1.2MHzのスプリアス改善効果はあま
り期待できないが、最も問題となる基本共振周波
数455KHzに隣接する650KHzのスプリアス改善効
果が高くなつている点で有効である。Spurious suppression amount dB 650KHz 950KHz 1.2MHz Conventional example 13.23 9.64 12.05 Example 1 15.83 10.40 12.58 Example 2 17.43 11.34 13.56 Example 3 14.76 11.30 12.26 Example 4 16.25 9.2 6 11.90 Example 5 15.28 12.02 13.82 As is clear from the above data , which implementation 1
.about.5, the spurious improvement effect on harmonics can also be obtained. In addition, in Example 4,
Although the spurious improvement effect at 950KHz and 1.2MHz cannot be expected much, it is effective in that the spurious improvement effect at 650KHz adjacent to the fundamental resonance frequency 455KHz, which is the most problematic, is enhanced.
しかも、上述のように、外側電極２のパターン
選択と言う簡単な方法によつて各高調波スプリア
スを改善できるので、製造が容易で、製造上の特
性バラツキ等を生じることなく、所期の高調波ス
プリアス抑圧作用を確実に引出し得る圧電磁器振
動子を提供することが可能である。 Moreover, as mentioned above, each harmonic spurious can be improved by the simple method of selecting the pattern of the outer electrode 2, so manufacturing is easy and the desired harmonic can be achieved without causing variations in manufacturing characteristics. It is possible to provide a piezoelectric ceramic vibrator that can reliably bring out the wave spurious suppression effect.
本考案の効果
以上述べたように、本考案は、平行四辺形の外
形を有して平板状に形成された圧電磁器素体の一
面上に、その外周縁に沿つて外側電極を設けると
共に、この外側電極の内側にギヤツプを隔てて内
側電極を設け、前記圧電磁器素体の他面側に前記
内側電極及び外側電極に共通に対向する共通電極
を設けた圧電磁器振動子において、前記圧電磁器
素体の少なくとも一つの隅部に、前記外側電極の
存在しない領域を有することを特徴とするから、
複数種の高調波スプリアスを確実に抑圧すること
ができ、しかも、製造が容易で、製造上の特性バ
ラツキ等を生じることなく、所期の高調波スプリ
アス抑圧作用を確実に引出し得る圧電磁器振動子
を提供することができる。Effects of the present invention As described above, the present invention provides an outer electrode along the outer periphery on one surface of a piezoelectric ceramic element having a parallelogram outer shape and formed into a flat plate. In the piezoelectric ceramic vibrator, an inner electrode is provided inside the outer electrode with a gap therebetween, and a common electrode is provided on the other surface side of the piezoelectric ceramic body, which commonly faces the inner electrode and the outer electrode. It is characterized by having a region where the outer electrode does not exist in at least one corner of the element body,
A piezoelectric ceramic vibrator that can reliably suppress multiple types of harmonic spurious, is easy to manufacture, and can reliably bring out the desired harmonic spurious suppressing effect without causing variations in manufacturing characteristics. can be provided.
第１図は従来の圧電磁器振動子の平面図、第２
図は第１図のA1−A1線上における断面図、第３
図は本考案に係る圧電磁器振動子の平面図、第４
図は第３図B1−B1線上における断面図、第５図
は従来の圧電磁器振動子の周波数−利得特性図、
第６図は第３図及び第４図に示した本考案に係る
圧電磁器振動子の周波数−利得特性図、第７図〜
第１０図は本考案に係る圧電磁器振動子の別々の
実施例における各平面図である。
１……圧電磁器素体、２……外側電極、３……
内側電極、４……共通電極、５，５１〜５４……
外側電極の存在しない領域。
Figure 1 is a plan view of a conventional piezoelectric ceramic vibrator;
The figure is a cross-sectional view taken along line A 1 - A 1 in Figure 1.
The figure is a plan view of the piezoelectric ceramic vibrator according to the present invention, No. 4
The figure is a sectional view taken along the line B1 - B1 in Figure 3, and Figure 5 is a frequency-gain characteristic diagram of a conventional piezoelectric ceramic vibrator.
FIG. 6 is a frequency-gain characteristic diagram of the piezoelectric ceramic vibrator according to the present invention shown in FIGS. 3 and 4, and FIGS.
FIG. 10 is a plan view of different embodiments of the piezoelectric ceramic vibrator according to the present invention. 1...Piezoelectric ceramic element body, 2...Outer electrode, 3...
Inner electrode, 4... Common electrode, 5, 51-54...
Area without outer electrodes.
Claims (1)
た圧電磁器素体の一面上に、その外周縁に沿つ
て外側電極を設けると共に、この外側電極の内
側にギヤツプを隔てて内側電極を設け、前記圧
電磁器素体の他面側に前記内側電極及び外側電
極に共通に対向する共通電極を設けた圧電磁器
振動子において、前記圧電磁器素体の少なくと
も一つの隅部に、前記外側電極の存在しない領
域を有することを特徴とする圧電磁器振動子。 (2) 前記領域は、前記隅部の頂角を構成する二辺
にかかるように設けられることを特徴とする実
用新案登録請求の範囲第１項に記載の圧電磁器
振動子。 (3) 前記領域は、前記圧電磁器素体の外周端縁か
ら前記ギヤツプに達し、前記外側電極を分断す
るように形成したことを特徴とする実用新案登
録請求の範囲第１項または第２項に記載の圧電
磁器振動子。 (4) 前記領域は、前記外側電極を分断せずに面積
を縮小するように形成したことを特徴とする実
用新案登録請求の範囲第１項または第２項に記
載の圧電磁器振動子。[Claims for Utility Model Registration] (1) An outer electrode is provided along the outer periphery on one surface of a piezoelectric ceramic element having a parallelogram outer shape and formed into a flat plate. In the piezoelectric ceramic vibrator, an inner electrode is provided on the inside of the piezoelectric ceramic element with a gap therebetween, and a common electrode is provided on the other side of the piezoelectric ceramic element, which commonly faces the inner electrode and the outer electrode. A piezoelectric ceramic vibrator having a region in which the outer electrode does not exist in at least one corner. (2) The piezoelectric ceramic vibrator according to claim 1, wherein the region is provided so as to span two sides forming the apex angle of the corner. (3) The area is formed to reach the gap from the outer peripheral edge of the piezoelectric ceramic body and divide the outer electrode, as claimed in claim 1 or 2 of the utility model registration claim. A piezoelectric ceramic vibrator described in . (4) The piezoelectric ceramic vibrator according to claim 1 or 2, wherein the region is formed so as to reduce the area without dividing the outer electrode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9235684U JPS617125U (en) | 1984-06-19 | 1984-06-19 | piezoelectric vibrator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9235684U JPS617125U (en) | 1984-06-19 | 1984-06-19 | piezoelectric vibrator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS617125U JPS617125U (en) | 1986-01-17 |
| JPH0241949Y2 true JPH0241949Y2 (en) | 1990-11-08 |
Family
ID=30649079
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9235684U Granted JPS617125U (en) | 1984-06-19 | 1984-06-19 | piezoelectric vibrator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS617125U (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0568820U (en) * | 1991-11-13 | 1993-09-17 | 和則 石井 | Gift storage box |
-
1984
- 1984-06-19 JP JP9235684U patent/JPS617125U/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS617125U (en) | 1986-01-17 |
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