JPS58213518A - Piezoelectric vibrator and its production - Google Patents

Abstract

PURPOSE:To fix the supporting stress of a piezo-diaphragm such as a crystal diaphragm and to obtain stable vibrator characteristics by housing the piezo- diaphragm and the supporting, by-pass and projection parts of a supporting member in a cylindrical case. CONSTITUTION:A cylindrical case 30 consists of a cylinder 31 and two caps 32. The cylinder 31 is obtained by molding an insulating material such as glass, ceramic or resin like a pipe, and said crystal diaphragm 10 and the supporting part 21, by-pass part 22 and projection part 23 of the supporting member 20 are contained in the cylinder 31. Although thermal or mechanical impact is applied at the time of sealing treatment, the impact is reduced and the supporting stress of the supporting member 20 can be kept almost at a fixed value because the by-pass part is inserted into the supporting member.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a piezoelectric vibrator made of a rectangular piezoelectric diaphragm and a method for manufacturing the same.

A crystal oscillator is widely known as this type of piezoelectric oscillator.
There is also a support member that supports the rectangular crystal diaphragm, but a support member with axes extending in opposite directions from both longitudinal ends of the support member allows the oscillator to be mounted on the surface. Although it is convenient, it has not yet been put into practical use.

For example, as shown in FIG. 1, a rectangular crystal diaphragm 1 is supported near both longitudinal ends by support members 2 and housed in a cylindrical container 3.
While maintaining the supporting stress of the crystal diaphragm 1 constant,
It was difficult to make it airtight. In other words, as the airtight process is subjected to mechanical shocks such as press-fitting and cold-open pressure welding, and thermal shocks such as welding and high-temperature soldering due to metal film baking, the support stress of the support member 2 suddenly changes, and the crystal resonator It was changing the various characteristics of.

An object of the present invention is to provide a piezoelectric vibrator which eliminates the above-mentioned drawbacks, makes the supporting stress of a piezoelectric diaphragm such as a quartz diaphragm constant by a support member during airtight treatment of a cylindrical container, and exhibits stable vibrator characteristics. and its manufacturing method,
Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIGS. 2(a), 2(b) and 2(c) show an embodiment of a crystal resonator according to the present invention, in which a crystal diaphragm 10
The excitation electrodes 12 and 13 to be vibrated by thickness sliding on the bidirectional surfaces of the AT-cut rectangular crystal plate 11, and the extraction electrodes 14 drawn out from the excitation electrodes 12 and 13 in opposite directions to the periphery in the longitudinal direction, 15 are arranged by vacuum evaporation or sputtering. The support member 20 is machined from a metal plate such as brass or Kovar material, and has a shaft 24 extending in opposite directions from near both ends of the extraction electrodes 14 and 15 along the longitudinal direction of the crystal diaphragm 10. a support part 21 that supports the crystal diaphragm 10; a four-turn part 22 that is curved on both sides of the shaft 24, has a hole in the center to form a 0-shape, and is detoured in a direction perpendicular to the longitudinal direction; It is provided with protrusions 23 protruding from both sides of the shaft 24, and is formed by etching, press working, or the like. Then, the drawer ff1 of the crystal diaphragm 1o
The vicinity of both ends of the ri 14 and 15 are placed on the support part 21 of the support member 2o, and conductive adhesive 25 is applied by applying a conductive adhesive or soldering to support and fix the crystal diaphragm 1° to the support member 2o. . The cylindrical container 3o has a cylinder 31 and two +t
The cylinder 31 is made of an insulating material such as glass, tramic or resin and formed into a pipe shape.
The crystal diaphragm 1o and the support portion 21, detour portion 22, and protrusion portion 23 of the support member 2o are accommodated therein. The openings at both ends of this cylinder 31 are covered with round tabs 32 made of metal such as nickel silver or brass, and a hole 33° is bored near the center of the axis of the +yudge. When covering the seven moons 3, the terminal-side shaft 24 of the support member 20 passes through the hole 33. Then, the outer surface of the cylinder 31 and the
Air-tight processing of the opening with the inner surface of the joint 32 is performed by high-temperature soldering or by applying a heat-resistant adhesive. In addition, for this airtight treatment, a nickel chromium layer is attached as a lower layer and a soft metal film such as silver as an upper layer on the outer surface of the cylinder 31, and the inner diameter of the cap 32 is adjusted to a size that removes the soft metal film. If this setting is made, it is possible to mechanically press-fit the cylinder 31 with the aforementioned two-layered outer surface and the +Yaffe 32 with the recommended inner surface. If the dimensions are set, it is also possible to weld the fitting onto the silver film and perform so-called metal plating/desigguing.

In any case, during the airtight treatment, thermal or mechanical shock is applied, but according to the present invention, the four-turn portion 22 of the support member 2°
Because of the presence of the support member 2o, the impact can be alleviated and the support stress of the support member 2o can be maintained substantially constant.

Next, in the gap between the hole 33 of the carriage 32 and the terminal-side shaft 24 of the support member 20 penetrating therefrom, a filler 34 such as high-temperature soldering or heat-resistant adhesive coating is applied to make the cylindrical container 30 airtight. . During filling, the filler 34 flows into the support member 2o inside the cylinder 31, but according to the invention, the protrusion 2o
3, the inflow can be prevented to ensure a constant support stress of the support member 20.

The support member 2o described above is shown in a detailed perspective view in FIG. 3(A), and as a modification thereof, as shown in FIG. I don't but V
It may be formed in a shape such as a letter or an S letter.

The protrusions 23 preferably protrude from both sides of the shaft 24 as in this example, but may protrude from one side.

Next, Figure 4 (a), CI]), (c) and (d)
shows an example of the method for manufacturing a crystal resonator according to the present invention,
First, the vicinity of both longitudinal ends of the extraction electrodes 14 and 15 of the crystal diaphragm 10 are placed on the support part 21 of the support member 20 which is integrally formed with the common holding member 26 in advance, and supported by the conductive adhesive 25. After fixing, the support member 20 is attached to the common holding member 2.
Separate it from 6 ((a), (l]) in the same figure).

Next, the support member 20 supporting and fixing the crystal diaphragm 10 is housed in the cylinder 31 (FIG. 3(C)), and the shaft 24 on both terminal sides of the support member 20 is passed through the hole 33 of the +Yapu 32.
The tube 32 is placed over the cylinder 31, and the gap between the cylinder 31 and the cap 32 and the gap between the hole 33 of the tube 32 and the shaft 24 of the support member 2o is air-tightened as described above.

According to such a manufacturing method, in addition to the mitigating effect of the above-mentioned detour portion 22 against the mechanical or thermal shock that occurs during the airtight process, the shaft 24 of the support member 20 during the airtight process penetrates through the hole 33 of the cap 32, so rotational movement around the shaft 24 and movement in the longitudinal direction of the shaft 24 are freely ensured, and the impact is further alleviated by these movements, and the support member 20 Therefore, the supporting stress on the crystal diaphragm 10 can be maintained constant.

In the above embodiments, a cylindrical container was used, but in the present invention, a rectangular or elliptical container may also be used.In addition to a quartz plate as a piezoelectric plate, lithium tacitate, The present invention can also be carried out with piezoelectric plates such as lithium diphosphate or piezoelectric t-ramic.Furthermore, the shaft on the terminal side of the support member becomes the terminal of the vibrator, but if this is cut off, the cap can be attached to the terminal. It is also possible to provide a piezoelectric vibrator in the shape of a tube.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing the structure of a conventional crystal resonator, Figure 2 (
A), (0) and (C) show the structure of a crystal resonator which is an embodiment of the present invention; 1, FIG. 3 (A) and (U) are detailed perspective views showing the supporting member; FIG. (stomach). ([1), (c), and (d) are diagrams showing a method for manufacturing a crystal resonator according to an embodiment of the present invention. 10...Crystal diaphragm, 11...Crystal plate, 12, 1
3... Excitation electrode, 20, 20'... Support member,
21. , support portion, 22 , 22°...detour portion, 23
...Protruding portion 1.24...shaft, 25...conductive adhesive,
30... Cylindrical container, 31... Cylindrical, 32... Kiya Soji, 33... Hole Patent applicant, Zt Ju Co., Ltd., Representative Takehiko Oda (-゛)

Claims (5)

[Claims] (1) In a piezoelectric vibrator in which the vicinity of both longitudinal ends of a piezoelectric diaphragm, in which excitation electrodes are arranged on the bidirectional surfaces of a rectangular piezoelectric plate, are supported by support members whose axes extend in the longitudinal direction in opposite directions. , the support member forms a support part supporting the piezoelectric diaphragm, a detour part rotated from the shaft in a direction perpendicular to the longitudinal direction, and a protrusion part protruding from the shaft, and the piezoelectric diaphragm A piezoelectric vibrator characterized in that the support part, the circular part, and the protrusion part of the support member are housed in a cylindrical container. (2) The piezoelectric vibrator according to claim 1, wherein the detour portion is formed in a 0-shape, a U-shape, a 4V-shape, or an S-shape. (3) A piezoelectric vibrator as set forth in claim 1, characterized in that the cylindrical container comprises a cylinder and a cap covering open portions at both ends of a core portion. (4) In claim 3, the core portion is made of an insulating material, the +P tube is made of a metal material, and the outer surface near the openings at both ends of the core portion and the inner surface of the cap are sealed by airtight treatment. A piezoelectric vibrator characterized in that a gap between a hole formed in the cap and a hole passing through the shaft on the terminal side of the support member is sealed. (5) A piezoelectric vibrator in which the vicinity of both longitudinal ends of a piezoelectric diaphragm, in which excitation electrodes are arranged on the bidirectional surfaces of a rectangular piezoelectric plate, are supported by support members whose axes extend in the longitudinal direction in opposite directions. In the manufacturing method, a support part that supports the piezoelectric diaphragm, a detour part that detours from the axis in a direction perpendicular to the longitudinal direction, and a protrusion part that protrudes from the axis are formed in advance on the support member, The vicinity of both longitudinal ends of the piezoelectric diaphragm are conductively bonded to the support portion of the support member, and then the piezoelectric diaphragm, the support portion, the detour portion, and the protrusion portion of the support member are attached to the inside of the cylinder. At the same time, the core part and the cap are airtighted by covering the openings at both ends of the core part with +yudges and passing the shaft on the terminal side of the support member through the hole made in the cap, A method for manufacturing a piezoelectric vibrator, characterized in that a gap between the shaft of the support and the shaft of the support is sealed.