JPH10209799A - Vibrator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a vibrator that is used for a communication equipment or the like against external noises and to avoid effects of internal radiation from the vibration onto other components. SOLUTION: A conductor 20 is formed to the inside of a 2nd cover 2, and the conductor 20 has electric continuity to a 2nd external electrode 15 via a 2nd through-hole 9 made on a diaphragm 3 and a 2nd through-hole 11 on a 1st cover 1, to allow the conductor 20 to act as an electric shield for the vibrator. Thus, the vibrator is protected against external noises, and the effects by internal radiation from the vibrator onto other components is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibrator used for communication equipment and the like.

[0002]

2. Description of the Related Art Conventionally, a quartz oscillator has been known as this type of oscillator. The crystal oscillator is shown in FIGS. FIG. 3A shows an external shape of a conventional crystal unit, and FIG. 3B shows a cross-sectional shape thereof. 3, reference numeral 1 denotes a first cover, and 2 denotes a second cover having a thickness of 400.
3 is a diaphragm with a thickness of 100 μm
It is composed of a quartz plate. The first cover 1 and the second cover 2 are directly joined to the front and back surfaces of the diaphragm 3.

[0003] Reference numeral 4 denotes a tongue-shaped vibrating portion formed on the vibrating plate 3, and 6 denotes an excitation electrode formed on the front and back surfaces of the vibrating portion 4. Reference numeral 7 denotes a lead electrode extracted from the excitation electrode 6. Reference numeral 10 denotes a through hole formed in the first cover 1;
Is a sealing electrode, and 14 is an external electrode. The sealing electrode 12 covers the through hole 10 to maintain airtight sealing. The lead electrode 7 and the external electrode 14 are electrically connected to each other by the sealing electrode 12 through the through hole 10.

Next, the internal structure of the crystal unit will be described with reference to FIG. 4 (a) and 4 (c) show the external shape of the crystal unit, and FIG.
(C) shows the external shape viewed from below. FIG. 2B is an exploded perspective view of the crystal unit viewed from above, showing the second cover 2, the diaphragm 3, and the first cover 1 from above. Similarly, (d) is an exploded perspective view of the crystal unit viewed from below, and shows the second cover 2, the diaphragm 3, and the first cover 1 from above.

In FIG. 4, a diaphragm 3 is formed with a U-shaped cut groove 5 inside thereof, whereby a tongue-shaped vibrating portion 4 is formed.
Are formed. Excitation electrodes 6 are formed on the front and back surfaces of the vibrating portion 4, and the lead electrodes 7 are drawn out through the root portions of the vibrating portion 4, respectively. One end of the lead electrode 7 penetrates the diaphragm 3 through the through hole 8, and then extends to the side opposite to the root through the side of the vibrating part 4. Each of these lead electrodes 7 is electrically connected to an external electrode 14 via a corresponding through hole 10 formed in the first cover 1.

The diaphragm 3 is sandwiched between the first cover 1 and the second cover 2 at the outer peripheral portions of the front and back surfaces, and is directly joined.
Are connected at the outer peripheral portion of the vibrating portion 4 and the lead electrode 7 passes through the side of the vibrating portion 4.
The outer side is joined to the first cover 1 and the second cover 2.

[0007]

However, in the above-described configuration, since the electrode portion having a shielding effect is not provided, the reference frequency of the crystal resonator often fluctuates due to external noise or the like. There is a problem that the radiation from the crystal unit affects other components to change the frequency.

In view of the above problems, the present invention provides a conductor inside a cover of a quartz oscillator, and electrically connects the conductor with an external electrode so that the conductor functions as an electric shield, and the noise is caused by external noise. It is an object of the present invention to provide a crystal resonator in which the reference frequency of the crystal resonator does not fluctuate and which can prevent radiation from affecting other components.

[0009]

According to the present invention, there is provided a crystal resonator comprising: a conductor provided inside a cover of the crystal resonator; and the conductor is electrically connected to an external electrode. Thus, the conductor functions as an electric shield, and it is possible to prevent fluctuation of the reference frequency of the crystal unit due to external noise, and to prevent influence of radiation on other components.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is directed to a diaphragm having a tongue-shaped vibrating portion, excitation electrodes provided on each of the front and back surfaces of the diaphragm, A lead electrode drawn out from each of the excitation electrodes to the base of the vibrating portion, first and second covers for sandwiching the front and back surfaces of the vibrating plate with their outer peripheral portions, and an outer portion of the first cover And a conductor provided inside the second cover, and electrically connects the first external electrode and the lead electrode. A second external electrode is formed by electrically connecting the conductor, and by connecting the second external electrode to the ground, the conductor is electrically shielded from external noise and internal radiation of the vibrator. Has the effect of working as.

According to a second aspect of the present invention, the first cover is provided with first and second through-holes, and the first external electrode and the lead electrode are electrically connected through the first through-hole. , A second external electrode and a conductor are connected through the second through hole, and the conductor is electrically connected to external noise and internal radiation of the vibrator by a very simple configuration. It has the effect of acting as a shield.

According to a third aspect of the present invention, the conductor is formed of a conductive paste or a thin metal film, or the conductor is made of at least Au, Ag, Cu, Cr, or Ni. It contains one or more components, and all have the effect that the conductor can be easily formed by using a thin film printing technique such as screen printing or a thin film forming technique such as vapor deposition or sputtering. Have.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. The vibrator according to the embodiment of the present invention shown in FIGS. 1 and 2 has basically the same configuration as the conventional vibrator shown in FIGS. 3 and 4, and the same components are denoted by the same reference numerals. And the detailed description is omitted.

(Embodiment 1) FIGS. 1A and 1B show an embodiment of the present invention, in which FIG. 1A shows its external shape and FIG. 1B shows its cross-sectional shape. In FIG. 1, reference numeral 9 denotes a second through hole formed in the diaphragm 3, and reference numeral 11 denotes a second through hole formed in the first cover 1. 13 is a second sealing electrode,
Reference numeral 15 denotes a second external electrode. Reference numeral 20 denotes a conductor formed inside the second cover, and reference numeral 21 denotes an auxiliary electrode formed in the second through hole 9.

Next, features of the present embodiment will be described with reference to FIG. 2A is an external view as viewed from above, FIG. 2B is an exploded perspective view thereof, FIG. 2C is an external view as viewed from below, and FIG. 2D is an exploded perspective view thereof. In the figure, the second through-hole 9 is processed at the same time when the cut groove 5 and the through-hole 8 of the diaphragm 3 are processed by sandblasting and / or etching. After that, the excitation electrode 6 and the lead electrode 7 are formed on the front and back surfaces of the diaphragm 3 by a thin film forming technique such as vapor deposition or sputtering in the same manner as in the conventional technique.

At this time, an auxiliary electrode 21 is also formed inside the second through hole 9. In addition, the first cover 1 processes the first through-hole 10 and the second through-hole 11 from one side by sandblasting or etching or both,
A recess is formed on the other surface. This other surface is later directly joined to the diaphragm 3 at the outer peripheral portion. However, since the other surface side of the first through hole 10 is in a position where it comes into contact with the lead electrode 7, the thickness of the lead electrode 7 is not less than Step is provided.

The other surface of the second through hole 11 is machined so as to coincide with the second through hole 9 formed in the diaphragm 3, and the diameter of the second through hole 11 is the second through hole 9. Is larger than the hole diameter of the through hole 9. Further, the peripheral portion of the second through hole 11 and the diaphragm 3 are directly joined. With respect to the second cover 2, a concave portion is formed on the surface side directly joined to the diaphragm 3 later, and the conductor 20 is formed inside the concave portion.

The conductor 20 may be formed by a thick film printing technique such as screen printing using a conductive paste, or by a thin film forming technique such as vapor deposition or sputtering. Au, Ag, Cu, Cr, Ni or the like may be used. Desirably contains at least one material having a low internal resistance.

As shown in FIG. 1 and FIG. 2, the recessed portion formed in the second cover 2 has a second through hole 11 formed in the first cover 1 and a second through hole 11 formed in the diaphragm 3. A position facing the through hole 9 is provided with a certain level difference, and a conductor 20 is also formed on this facing surface. In addition, the step on the facing surface needs to be at least the thickness of the conductor 20. Then, after the first cover 1, the second cover 2, and the diaphragm 3 are individually formed, they are directly joined to a predetermined position.

Thereafter, in a vacuum state, the first sealing electrode 12 and the second sealing electrode 1 are formed in the first through hole 10 and the second through hole 11 by vapor deposition or sputtering.
Form 3 At this time, the inside of the vibrator is the first sealing electrode 1.
It is hermetically sealed by the second and second sealing electrodes 13.
Further, the first sealing electrode 12 is electrically connected to the lead electrode 7, and the second sealing electrode 13 is electrically connected to the conductor 20. The degree of adhesion of the second sealing electrode 13 is increased by an auxiliary electrode 21 formed on the diaphragm 3. After that, a first external electrode 14 is formed on the first sealing electrode 12 so as to fill a step of the first through hole 10, and a second penetrating electrode is formed on the second sealing electrode 13. A second external electrode 15 is formed so as to fill a step of the hole 11 to form a crystal resonator.

[0021]

As described above, according to the present invention, the conductor is formed inside the second cover of the vibrator, and the conductor is electrically connected to the external electrode. The vibrator can have a shielding effect. as a result,
An object of the present invention is to provide a crystal resonator that does not cause a change in a reference frequency of the crystal resonator due to external noise and can prevent radiation from affecting other components.

[Brief description of the drawings]

FIG. 1A is an external view of a crystal unit according to an embodiment of the present invention, and FIG.

2A is an external view of the crystal resonator according to the embodiment as viewed from above, FIG. 2B is an exploded perspective view of the same, and FIG. Figure

FIG. 3A is an external view of a conventional crystal unit. FIG.

FIG. 4A is an external view of the conventional example as viewed from above. FIG. 4B is an exploded perspective view of the conventional example. FIG.

[Description of Signs] 1 First cover 2 Second cover 3 Vibrating plate 4 Vibrating part 5 Cut groove 6 Excitation electrode 7 Lead electrode 8 Through hole 9 Second through hole 10 First through hole 11 Second through Hole 12 First sealing electrode 13 Second sealing electrode 14 First external electrode 15 Second external electrode 20 Conductor 21 Auxiliary electrode

Claims (5)

[Claims] 1. A diaphragm having a tongue-shaped vibrating portion, excitation electrodes provided on each of a front surface and a rear surface of the vibration plate, and each of the excitation electrodes pulled out to a root portion of the vibration portion. A lead electrode, first and second covers for sandwiching the front and back surfaces of the diaphragm at their outer peripheral portions, first and second external electrodes provided outside the first cover, A conductor provided inside the second cover, for electrically connecting the first external electrode and the lead electrode, and electrically connecting the second external electrode to the conductor; A vibrator characterized in that the vibrator is operated. A first cover provided with first and second through-holes to electrically connect the first external electrode and the lead electrode via the first through-hole; The vibrator according to claim 1, wherein an electrode and a conductor are connected through the second through hole. 3. The vibrator according to claim 1, wherein the conductor is formed of a conductive paste. 4. The vibrator according to claim 1, wherein the conductor is formed of a metal thin film. 5. The conductor is made of Au, Ag, or C.
The vibrator according to claim 1, further comprising at least one of u, Cr, and Ni.