JPH0332832U

JPH0332832U -

Info

Publication number: JPH0332832U
Application number: JP9270389U
Authority: JP
Priority date: 1989-08-07
Filing date: 1989-08-07
Publication date: 1991-03-29
Anticipated expiration: 2004-08-07
Also published as: JP2563654Y2

Description

[Brief explanation of the drawing]

第１図ａおよびｂは本考案の一実施例に係る圧
電フイルタの片面側および他面側を同じ方向から
見た平面図、第２図ａおよびｂは同圧電フイルタ
の圧電基板形状の変形例の片面側および他面側を
同じ方向から見た平面図、第３図ａおよびｂは本
考案の他の実施例に係る圧電フイルタの片面側お
よび他面側を同じ方向から見た平面図、第４図ａ
およびｂは同圧電フイルタの圧電基板形状の変形
例の片面側および他面側を同じ方向から見た平面
図、第５図は音叉型の圧電フイルタの振動モード
を示す説明模式図、第６図ａ，ｂはそれぞれ第１
図、第２図に示す圧電フイルタの外装の一例を示
す斜視図、第７図は第１図に示す圧電フイルタの
外装の他の例を示す分解斜視図、第８図は本考案
に係る圧電フイルタの各電極の位置関係を示す模
式図、第９図は同圧電フイルタの等価回路図、第
１０図ａ，ｂ，ｃ，ｄはそれぞれ第１電極および
第２電極の電極形成領域条件を示す模式図、第１
１図ａは電極の電荷分布を測定するための接続図
、第１１図ｂは同電極の電荷分布曲線図、第１２
図ａは第１図に示す圧電フイルタの一例の特性グ
ラフ、第１２図ｂは従来の角板広がりモード振動
型の圧電フイルタの一例の特性グラフ、第１３図
ａおよびｂは同圧電フイルタの片面側および他面
側を示す平面図、第１３図ｃは同圧電フイルタの
斜視図、第１４図ａ，ｂ，ｃは同圧電フイルタの
振動の状態を示す説明模式図、第１５図は同圧電
フイルタの等価回路図、第１６図ａおよびｂは従
来の音叉型の圧電フイルタの片面側および他面側
を示す平面図、第１７図は同圧電フイルタの等価
回路図、第１８図は同圧電フイルタの各電極の位
置関係を示す模式図である。符号の説明、１，１ａ，１ｂ，１ｃ……圧電フ
イルタ、２……圧電基板、３……スリツト、４…
…腕部、５……音叉部、７……第１電極、８……
第２電極、９……第３電極、１０……第４電極。 1A and 1B are plan views of one side and the other side of a piezoelectric filter according to an embodiment of the present invention viewed from the same direction, and FIGS. 2A and 2B are modified examples of the piezoelectric substrate shape of the same piezoelectric filter. 3A and 3B are plan views of one side and the other side of a piezoelectric filter according to another embodiment of the present invention viewed from the same direction, Figure 4a
and b are plan views of one side and the other side of a modified example of the piezoelectric substrate shape of the same piezoelectric filter, viewed from the same direction, Fig. 5 is an explanatory schematic diagram showing the vibration mode of a tuning fork type piezoelectric filter, and Fig. 6 a and b are the first
2, FIG. 7 is an exploded perspective view showing another example of the piezoelectric filter exterior shown in FIG. 1, and FIG. 8 is a piezoelectric filter according to the present invention. A schematic diagram showing the positional relationship of each electrode of the filter, Fig. 9 is an equivalent circuit diagram of the same piezoelectric filter, and Fig. 10 a, b, c, and d show the electrode formation area conditions of the first electrode and the second electrode, respectively. Schematic diagram, 1st
Figure 1a is a connection diagram for measuring the charge distribution of an electrode, Figure 11b is a charge distribution curve diagram of the same electrode, and Figure 12 is a diagram of the charge distribution curve of the same electrode.
Figure a is a characteristic graph of an example of the piezoelectric filter shown in Figure 1, Figure 12 b is a characteristic graph of an example of a conventional square plate spreading mode vibration type piezoelectric filter, and Figures 13 a and b are one side of the same piezoelectric filter. FIG. 13c is a perspective view of the piezoelectric filter, FIGS. 14a, b, and c are schematic explanatory diagrams showing the vibration states of the piezoelectric filter, and FIG. 15 is a perspective view of the piezoelectric filter. Equivalent circuit diagram of the filter, Figures 16a and b are plan views showing one side and the other side of a conventional tuning fork type piezoelectric filter, Figure 17 is an equivalent circuit diagram of the same piezoelectric filter, and Figure 18 is the same piezoelectric filter. It is a schematic diagram showing the positional relationship of each electrode of a filter. Explanation of symbols: 1, 1a, 1b, 1c...Piezoelectric filter, 2...Piezoelectric substrate, 3...Slit, 4...
...Arm part, 5...Tuning fork part, 7...First electrode, 8...
2nd electrode, 9...3rd electrode, 10...4th electrode.

Claims

[Claims for Utility Model Registration] 1. A piezoelectric filter formed by forming a plurality of electrodes on a piezoelectric substrate, a tuning fork portion formed by cutting at least one slit into the piezoelectric substrate and forming arms on both sides of the slit; A first electrode and a second electrode are provided on one side of the piezoelectric substrate near the periphery of the slit and are separated on both sides of the slit; a third electrode facing the first electrode and short-circuited to the second electrode; and a third electrode provided on the other side of the piezoelectric substrate and facing the second electrode and formed separately from the third electrode. 4th to be done
A piezoelectric filter comprising an electrode. 2. A piezoelectric filter having a plurality of electrodes formed on a piezoelectric substrate, a tuning fork portion formed by cutting at least one slit in the piezoelectric substrate and configuring both sides of the slit as arm portions; A first electrode and a second electrode are provided along the outer edge of the arm with respect to the slit, and the first electrode and the second electrode are provided separately on both sides of the slit, and the electrode is provided on the other side of the piezoelectric substrate. a third electrode facing the first electrode and short-circuited to the second electrode; and a third electrode provided on the other side of the piezoelectric substrate and facing the second electrode and formed separately from the third electrode. 4th to be done
A piezoelectric filter comprising an electrode.