JPH0332829U

JPH0332829U -

Info

Publication number: JPH0332829U
Application number: JP9162389U
Authority: JP
Priority date: 1989-08-03
Filing date: 1989-08-03
Publication date: 1991-03-29
Anticipated expiration: 2004-08-03
Also published as: JP2516083Y2

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，ｂはそれぞれ同圧電フイ
ルタの他面側の電極形状の変形例を示す平面図、
第３図ａ，ｂ，ｃはそれぞれ同圧電フイルタの片
面側の各電極形状の変形例を示す平面図、第４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４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図は第１
図、第４図に示す圧電フイルタの等価回路図、第
９図ａ，ｃおよびｂ，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
１０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１０図ｂは従来の角板拡がりモード
振動型の圧電フイルタの一例の特性グラフ、第１
１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１１図ｃは同圧電フイル
タの斜視図、第１２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１３図は同
圧電フイルタの等価回路図、第１４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１５図は同圧電フイルタの
等価回路図である。符号の説明、１，１ａ……圧電フイルタ、１…
…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。 Figures 1a and b 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 Figures 2a and b are electrodes on the other side of the piezoelectric filter, respectively. A plan view showing a modified example of the shape,
FIGS. 3a, b, and c are plan views showing modified examples of the shape of each electrode on one side of the same piezoelectric filter, respectively, and FIGS. A plan view of the other side viewed from the same direction, FIG. 5 is an explanatory schematic diagram showing the vibration mode of a tuning fork type piezoelectric filter, and FIGS. 6 a and b are views of the piezoelectric filter shown in FIGS. 1 and 4, respectively. FIG. 7 is an exploded perspective view showing another example of the exterior of the piezoelectric filter shown in FIG.
Figure 9 is an equivalent circuit diagram of the piezoelectric filter shown in Figure 4, Figures 9a, c, b, and d are schematic diagrams showing the electrode formation area conditions of the first and second electrodes, respectively, and Figure 10a is a schematic diagram of the piezoelectric filter shown in Figure 4. Figure 10b is a characteristic graph of an example of a piezoelectric filter shown in the figure.
Figures 1a and 1b are plan views showing one side and the other side of the piezoelectric filter, Figure 11c is a perspective view of the piezoelectric filter, and Figures 12a, b, and c show the state of vibration of the piezoelectric filter. Fig. 13 is an equivalent circuit diagram of the same piezoelectric filter, Fig. 14 a and b
1 is a plan view showing one side and the other side of a conventional tuning fork type piezoelectric filter, and FIG. 15 is an equivalent circuit diagram of the same piezoelectric filter. Explanation of symbols, 1, 1a...Piezoelectric filter, 1...
...Piezoelectric substrate, 3...Slit, 4...Arm, 5...
... Tuning fork part, 7 ... First electrode, 8 ... Second electrode, 9
...Third electrode.

Claims

[Claims for Utility Model Registration] A piezoelectric filter comprising a plurality of electrodes formed on a piezoelectric substrate, comprising: 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 provided on one side of the piezoelectric substrate and formed near the periphery of the slit; and a first electrode provided on one side of the piezoelectric substrate separately from the first electrode and on one side with respect to the slit. A second electrode formed along the outer edge of the arm, and a third electrode provided on the other side of the piezoelectric substrate and facing the first electrode and the second electrode. A piezoelectric filter characterized by: