JPH08330888A - Ceramic resonator - Google Patents

Abstract

PURPOSE: To provide a ceramic resonator attaining miniaturization (small area). CONSTITUTION: Terminal plates 11a to 11c consisting of metalic material are integrated to a cap case 10 housing a capacitive element 3 and a piezoelectric element 6 to engage an insulated substrate 12 with the level difference part 10b of an opening part. Then the other terminals 11d to 11f of the terminal plates 11a to 11c are bent to the side of the outside of the insulated substrate 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic resonator utilizing the vibration of a piezoelectric element.

[0002]

2. Description of the Related Art Ceramic resonators are electronic parts that are expected to develop in the future as indispensable electronic parts for clock oscillation for microcomputers and oscillations of various remote control devices.

A conventional ceramic resonator will be described below. FIG. 5 is an external perspective view of a conventional ceramic resonator,
FIG. 6 is an enlarged cross-sectional view of the main part, and FIG. 7 is an equivalent circuit diagram thereof. Note that FIG. 6 shows only the left half because of left-right symmetry.

A first electrode 2a, a second electrode 2b, and a third electrode 2c are provided on the front and back surfaces of the insulating substrate 1 at regular intervals, and have a semicircular cutout shape formed on the side surface of the insulating substrate 1. Electrical connection between the front and back is achieved via the side surface electrodes 2d, 2e, 2f. The capacitive element 3 is in the form of a thin plate, and a front electrode 4a, a right front electrode (not shown) symmetrical to the front electrode 4a, and a back electrode 4b form two capacitances (capacitors) in the longitudinal direction. Each electrode 2a, 2 of the insulating substrate 1
b and 2c and the electrodes 4a, 4b and 4c of the capacitive element 3 are the first electrode 2a and the front side electrode 4a, the second electrode 2b and the back side electrode 4 respectively.
b, each connection between the third electrode 2c and the front electrode is a conductive adhesive 5
Is done by.

The piezoelectric element 6 has a thin plate shape and is provided with a front electrode 7a and a back electrode 7b. Both ends of the piezoelectric element 6 in the lengthwise direction are electrically conductive adhesive 5 and the front electrode 4a of the capacitive element 3 and the piezoelectric element 6 are provided.
The front side electrode 7a, the front side electrode 4c, and the back side electrode 7b are connected to each other. The cap case 8 has an opening 8a at one end and a hollow portion 8b inside, and the outer peripheral side surface 8c is a box having a U-shaped cross section that is a linear plane. The hollow portion 8b has a capacitive element 3 and a piezoelectric element 6 therein. And the opening 8a is hermetically fixed on the insulating substrate 1 with an adhesive 9. The above configuration is shown in an equivalent circuit in FIG. 7, which is a ceramic resonator in which the piezoelectric element 6 and the capacitors A and B are housed at the same time.

[0006]

SUMMARY OF THE INVENTION In the above conventional configuration,
The surface electrodes 2a, 2b, 2c of the insulating substrate 1 are flat with a constant film thickness, and the opening 8a of the cap case 8 is also flat, so that the adhesive 9 between the insulating substrate 1 and the cap case 8 is used. If the side surface 8c of the cap case 8 is too close to the semicircular cutout side surface electrodes 2d, 2e, 2f of the insulating substrate 1, the adhesive 9 causes the side surface electrodes 2d, 2e, 2f to come into contact with each other. Flow into the solder and lead to poor soldering. In consideration of these preventions, it is necessary to make the size of the insulating substrate 1 to be a large area in consideration of mounting misalignment, so that there is a problem that the mounting area becomes large.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a ceramic resonator whose area can be easily reduced during mounting.

[0008]

In order to achieve this object, the present invention provides a cap case having a U-shaped cross section having a step inside the opening end, a capacitive element housed in the cap case, and A piezoelectric element and an insulating substrate fitted to the step inside the opening end of the cap case,
After pulling out the other end of the metal terminal plate, one end of which is electrically connected to the piezoelectric element inside the cap case, from the top or side of the cap case to the outside of the cap case, the insulating substrate at the open end of this cap case It is bent to the outside and used as an input and output terminal.

[0009]

According to this structure, the capacitative element and the piezoelectric element are housed in the cap case, the insulating substrate is fitted to the step inside the opening end of the cap case, and the other end of the metal terminal plate is capped. Since it is bent from the side of the case to the outer surface of the insulating board and used as input and output terminals, there is no misalignment of the cap case and it is possible to reduce the area of the insulating board.
Therefore, the mounting area can be reduced.

[0010]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a ceramic resonator according to an embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view of an essential part of the present invention, and FIG. 3 is an exploded perspective view showing its assembly configuration.
FIG. 3 shows only the left half because of left-right symmetry. Further, the same parts as those in the conventional example are designated by the same reference numerals.

The cap case 10 has an opening 10 at one end.
a, a stepped portion 10b inside the opening 10a, and a hollow portion 10c inside the box having a U-shaped cross section. The long terminal plates 11a to 11c made of a metal material are the cap case 1
In the vicinity of the top surface 10d of 0, one end is inserted into the internal cavity 10c, and three spaces are provided at regular intervals.
Also, the other ends 11d, 11e, 1 of the terminal plates 11a to 11c.
1f protrudes from both sides of the outer surface 10e of the cap case 10, is bent toward the opening 10a, and is finally bent toward the outer surface of the insulating substrate 12 fitted in the step portion 10b as shown in FIG. . The capacitive element 3 is a thin plate and has a front electrode 4
a, and the front side electrode 4c and the back side electrode 4 at symmetrical positions
Capacitance (capacitor) at two locations in the longitudinal direction depending on b
Are those that have. One end of each of the terminal plates 11a to 11c protruding into the cavity 10c of the cap case 10 is electrically connected to each of the electrodes 4a, 4b, 4c of the capacitive element 3 by the conductive adhesive 5.

The piezoelectric element 6 has a thin plate shape and is provided with a front side electrode 7a and a back side electrode 7b. Both ends in the lengthwise direction are covered with a conductive adhesive 5 and the front side electrode 4a of the capacitive element 3 and the piezoelectric element 6 are connected.
The front side electrode 7a, the front side electrode 4c and the back side electrode 7b are electrically connected to each other. That is, the terminal boards 11a to 1
1c is electrically connected to the capacitive element 3 and the piezoelectric element 6.

The insulating substrate 12 is fitted and installed in the step portion 10b of the opening 10a of the cap case 10, and the cap case for sealing the capacitive element 3 and the piezoelectric element 6 housed and installed in the cavity 10c. 10 and insulating substrate 12
Are bonded by the adhesive 9. In this state, the other ends 11d, 11e, 11 of the terminal plates 11a to 11c pulled out from the outer surface 10e of the cap case 10 as described above.
f is bent on the outer surface side of the insulating substrate 10 as shown in FIG.

In this embodiment, the insulating substrate 12 and the cap case 10 are adhered to each other by the adhesive agent 9. However, the same resin material is used for ultrasonic welding to achieve the joining and sealing. Is also possible.

With the above configuration, the size of the cap case 10 becomes the product size, and therefore the size can be reduced, and stable soldering is ensured by using the metal terminal plates 11a to 11c as terminals. It will be.

[0016]

As described above, according to the present invention, the capacitative element and the piezoelectric element are housed in the cap case, and the insulating substrate is fitted to the step inside the opening end of the cap case.
Furthermore, since the other end of the metal terminal plate is bent from the side surface of the cap case to the outer surface side of the insulating substrate to serve as an input / output terminal, the mounting displacement of the cap case does not occur, and it is possible to reduce the area of the insulating substrate. Therefore, the mounting area can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of a ceramic resonator showing an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of the main part of FIG.

FIG. 3 is an exploded perspective view of a ceramic resonator according to an embodiment of the present invention before assembly.

FIG. 4 is a side view of a ceramic resonator showing an embodiment of the present invention.

FIG. 5 is a perspective view of a conventional ceramic resonator.

FIG. 6 is an enlarged sectional view of a main part of a conventional ceramic resonator.

FIG. 7: Equivalent circuit diagram of ceramic resonator

[Explanation of symbols]

 3 Capacitance element 6 Piezoelectric element 10 Cap case 11a Terminal board 11b Terminal board 11c Terminal board 12 Insulation board

Claims (2)

[Claims] 1. A cap case having a U-shaped cross section having a step inside the opening end, a capacitive element and a piezoelectric element housed in the cap case, and a step inside the opening end of the cap case. Consisting of a combined insulating substrate, one end of which is electrically connected to the piezoelectric element in the cap case, the other end of which is pulled out from the top or side of the cap case to the outside of the cap case. A ceramic resonator that is bent to the outside of the insulating substrate at the open end of this cap case and used as the input and output terminals. 2. The ceramic resonator according to claim 1, wherein the cap case and the insulating substrate are made of the same material, and the fitting portion is joined by ultrasonic welding.