JPS60264108A - Manufacture for piezoelectric filter - Google Patents

Abstract

PURPOSE:To eliminate the need or the etching process and further to make the connecting state unchanged against split by splitting an electrode of a piezoelectric vibrator while the piezoelectric vibrator is fixed to a frame with a lead. CONSTITUTION:A conductor pattern 13 is formed to the front and back side around a cut-out part 12 of the frame 10. The electrode 15 is formed to the entire major surfaces opposite to each other of a ceramic vibrator 11 by means of printing. Nodes of the vibration of the vibrator 11 are supporte by the cut-out part 12 while the electrode 15 of the front and back sides is fixed to the lead wire 16. The end of the lead wire 16 is fixed to the conductor pattern 13. Solder 17 fixes the pattern 13 and the lead wire 16, and the lead wire 16 and the electrode 15. Then the lead wire 16 of the front side, the electrode 15 and the pattern 13 are split in this state. The middle part of the electrode 15 is split and the lead wire 16 is split at the soldered part. A split slit 18 is processed with high accuracy by a cutting machine. The lead wire 16 of the front side, the electrode 15 and the conductor pattern 13 are divided into two parts by this split and a 3-terminal type piezoelectric filter having input/output sides is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing a piezoelectric filter using a rectangular piezoelectric vibrator, mainly a three-terminal piezoelectric filter.

[Prior art and its problems]

FIG. 11 is an explanatory diagram of a conventional three-terminal piezoelectric filter.
．． Input electrode 3. Output electrodes 4 are provided, and lead wires are elastically connected to each electrode. A lead wire 7°8 is connected to the input electrode 3 and the output voltage fM4, which are divided, via an anisotropically conductive rubber sheet 6, and a lead wire 9 is in direct contact with the ground electrode 2, which is provided on the entire surface. are doing. The ceramic resonator 1 used has three electrodes formed in advance. The anisotropic conductive rubber sheet 6 is a ceramic resonator l
The role is to prevent misalignment due to vibration, etc. However, in order to provide divided electrodes on the ceramic resonator 1, it is necessary to form polarization electrodes on the entire surface, print a photoresist film, and then perform etching. Furthermore, when lead wires are connected to the ceramic vibrator 1, the characteristics such as the pass band tend to shift irregularly when measured by the ceramic vibrator 1 alone, depending on its elastic force and the state of connection, making adjustment cumbersome.

[Object of the present invention]

The purpose of the present invention is to improve these conventional drawbacks.

An object of the present invention is to provide a method for manufacturing a piezoelectric filter that efficiently forms divided electrodes of a ceramic vibrator and reduces deviation in characteristics due to lead wires.

[Structure and effects of the invention]

The method for manufacturing a piezoelectric filter of the present invention is to provide a punched part of a planar insulating frame, which has a conductive pattern on both the front and back surfaces around the punched part, and to apply electrodes to the entire surface of each of the two opposing sides of the punched part. A rectangular piezoelectric vibrator is supported with an electrode fixed to a lead wire that crosses the punched portion in a direction perpendicular to the length direction of the piezoelectric vibrator, and at least the lead wire and the electrode are separated. Therefore, the divided electrodes of the piezoelectric vibrator can be formed without going through an etching process, and irregular deviations in the characteristics of the piezoelectric vibrator can be prevented during the mounting process.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an explanation will be given with reference to FIGS. 1 to 4, which are perspective views showing an embodiment of a method for manufacturing a piezoelectric filter according to the present invention.

In Figures 1 to 4, 10 is a synthetic resin frame;
1 is a cheekbone-shaped ceramic vibrator.

The frame body 10 has a square punched part 12 in the center as shown in FIG.
sb, the overall planar shape is a mouth shape. A conductor pattern 13 is formed on both the front and back surfaces around the punched portion 12. ! 4 is a portion where the conductor pattern 13 is not present, but it is present all over the back surface. The ceramic vibrator 11 has stain electrodes 15 formed on each of the opposing main surfaces to prevent printing from burning. The ceramic resonator 11 is the second
As shown in the figure, the front and back electrodes 15 are fixed to lead wires 16 that cross the punched portion 12, and the vibration nodes are supported by the punched portion 12.

The ceramic vibrator 11 performs longitudinal vibration. The lead wire 16 crosses the punched portion 12 in a direction perpendicular to the longitudinal direction of the ceramic vibrator 11, and its end is fixed to the conductor pattern 13. 17 is the conductor pattern 13 and the lead wire 16. This is solder that fixes the lead wire 16 and the electrode 15. Then, in the state shown in FIG. 2, the lead wire 16, electrode 15, and conductor pattern 13 on the front side are divided as shown in FIG. The electrode 15 is divided at the center along its length, and the lead wire 16 is also divided at the soldered portion. Further, the position where the conductor pattern 130 is divided is on the extension line of the position where the electrode 150 is divided. 1B is a dividing groove, which can be cut using a cutting tool or similar cutting machine.

Depth and size can be determined with high precision.

Due to this division, the lead wire 16 on the front side is connected to the lead 16A.
The J-wire 16B and the electrode 15 form an electric piezoelectric filter with the electrode 15A. FIG. 6 is an equivalent circuit diagram of FIG. 3. For example, if the A side is the input side, the conductor pattern 13A and the conductor pattern 13B serve as input and output terminals, respectively.

The frame body 10 is covered with a flat plate-shaped lid body 19 and a lid body 20 of the same size from the front and back sides as shown in FIG. 4. Good 1 is a recess provided in the lid 20 so as not to inhibit the vibration of the ceramic vibrator 11, and a similar one is provided in the lid 19 as well. The planar size of the recessed portion 21 is the same as that of the punched portion 12.
is almost the same.

FIG. 5 is a perspective view of the assembled piezoelectric filter. 2
2, 23, and 24 are external terminals formed by applying conductive paint, and external terminal 22 is a conductor/4 Fil.
- turn 13A and external terminal 24 are connected to the conductor pattern (turn 13B and external terminal 23 are connected to the conductor pattern 13 on the back side, respectively).

The external terminal 23 connected to the undivided conductor butter y13 serves as an external terminal on the ground side. If the conductor pattern 13 and lead wire 16 on the back side are divided in the same way as on the front side, a four-terminal piezoelectric filter is obtained as shown in the equivalent circuit diagram of FIG. Although FIG. 10 is a perspective view of another piezoelectric filter, it is also possible to support two ceramic vibrators 32 in the punched portion 31 of the frame 30. conductor pattern 330
The dividing groove 86 is located in the middle of the juxtaposed ceramic vibrators 32, but may be located on the extension line of the dividing groove 35 on one side of the electrode 34.

8 and 9 are plan views showing another embodiment of the piezoelectric filter manufacturing method of the present invention.

A plurality of punched portions 41 are provided in the continuous elongated frame body 40.
A ceramic vibrator 42 is supported by a lead wire 43 in each punched portion 4L.
1J43u are fixed to the conductive patterns 44 on both the front and back surfaces of the frame body 40 with solder 45 every time the punched portion 41 is crossed. In this state, as shown in FIG. 9, the electrode 46 on the front side of the ceramic vibrator 420 is divided at the center along its length. Lead @43 and conductor pattern 44
The electrodes 46 are also divided along the dividing positions. 47 is a dividing groove. For example, by cutting and separating the frame 40 at a position indicated by a chain line, a piezoelectric filter in which three three-terminal type ceramic loss elements 42 are connected can be obtained. The conductor pattern 44 at the end serves as input and output terminals.

As in this embodiment, a piezoelectric filter having an arbitrary number of oscillators 42 can be easily obtained depending on the cutting position of the frame 40.A lid body having a shape corresponding to the frame 40 is prepared separately. It is also possible to almost complete the assembly at the time of cutting in a state where it is placed over the frame body 40.

In addition, in the manufacturing method of the present invention, there is no need to limit the shapes of the frame, the lid, and the external terminal. The frame body may have a planar shape and may be U-shaped. The lid body may also be box-shaped instead of the shape of the embodiment in which the lid body is divided into front and back parts. Alternatively, the outer terminal may be a metal piece soldered to the conductor pattern of the frame and pulled out. Furthermore, in the case of FIG. 10, the conductor pattern 33 may be separated in advance at the edge of the dividing groove 36 of the conductor pattern 330.

As described above, in the manufacturing method of the present invention, the electrodes are divided with the piezoelectric vibrator fixed to the frame by the lead wire, and an etching step is not necessary. Furthermore, the lead wires are also divided at the same time as the electrodes are divided, but since the electrodes and the lead wires are fixed and are separated, there is almost no change in the connection state.

Since a dividing groove is formed and the lead wires and solder are partially removed, the characteristics of the piezoelectric vibrator will slightly deviate when compared to before separation. can be easily predicted.

Furthermore, when the series lead wire is fixed to the electrode by soldering, welding, etc., there is less variation in the connection state compared to conventional elastic contact. Therefore, if the characteristics of the piezoelectric vibrator are adjusted in anticipation of subsequent changes in the two-terminal state before installation to the piezoelectric filter, deviations in characteristics due to time or separation of electrodes can be prevented during installation. Furthermore, even if it is necessary to adjust the characteristics by cutting the piezoelectric vibrator after installation, the work is easy because it is completely fixed. Thermal theory The piezoelectric filter obtained by the manufacturing method of the present invention has strong support for the vibrator and is also physically strong. Furthermore, assembly is performed with the piezoelectric vibrator fixed, and there is no need to fit the piezoelectric vibrator between sheets using anisotropically conductive rubber sheets, and manufacturing is easy.

[Brief explanation of drawings]

1 to 4 are perspective views showing an embodiment of the piezoelectric filter manufacturing method of the present invention, FIG. 5 is an assembled perspective view, and FIGS. 6 and 7 are equivalent circuit diagrams of the piezoelectric filter. 8 and 9 are plan views showing another implementation of the piezoelectric filter manufacturing method of the present invention, FIG. 10 is a perspective view of another piezoelectric filter according to the manufacturing method of the present invention, and FIG. 11 is a FIG. 2 is an explanatory diagram of a conventional piezoelectric filter. 10/30/408 frame body. ! !・32・42=ceramic oscillator. 12 buildings 31/41! Punching part. 13・13A・13B・33φ44@conductor pattern. 15-15A-15B-34-46 as electrode. 16/16A/16B-43: Lead wire. 18.35.36.47! Splitting groove. 19.20g lid body, 21: recess. 22, 23, 24; External terminal patent applicant Toko Co., Ltd. Figure 3 Figure 5 Figure II

Claims (1)

[Claims] A rectangular piezoelectric vibrator with electrodes formed on each of the two opposing sides is attached to the punched part of a planar insulating frame with conductive patterns on both the front and back sides around the punched part. A method for manufacturing a piezoelectric filter, characterized in that electrodes are supported in a fixed state on lead wires that cross a punched portion in a direction perpendicular to the length direction of the filter, and at least the lead wire and the electrodes are separated.