JPH0435311A - Crystal resonator for surface mount - Google Patents

Abstract

PURPOSE:To improve the secular change characteristic and the productivity by forming a step to an inner wall of a package main body, abutting one face at both ends of a crystal chip on the step, supporting the crystal chip with a flat elastic body mechanically and providing a frequency adjustment throughhole to the flat elastic body. CONSTITUTION:One side of an outer circumference of both ends of a crystal chip 1 is abutted on a step in a package main body 2. Then a metallic elastic plate 8 is interposed between a cover 3 and the other side of the crystal chip 1 and the crystal chip 1 is fixed by seam welding. The flat elastic body 8 is processed in H-shape so as to have legs 9a, 9b, 9c, 9d folded at both ends of the flat elastic body 8 and a throughhole 10 is provided in the middle. Then the middle part of the flat elastic body 8 is in press contact with the cover 3 and each leg 9 is press contact with the four corners of the crystal chip 1. Moreover, a lead electrode 4 prolonged to an outer circumference of both endsof the other side of the crystal chip 1 is connected to a conductor path 7 by bonding through a metallic thin wire 11.

Description

Detailed Description of the Invention (Industrial Field of Application) The field of the present invention is a crystal resonator for surface mounting. Concerning children.

BACKGROUND OF THE INVENTION Quartz crystals are useful as time or frequency reference sources, filter elements, and other essential components. in recent years,
Surface-mountable devices are desired, as typified by chip devices such as resistors and capacitors.

(Prior art) Figure 3 is a diagram explaining the basic configuration of such a conventional example.
Figure (a) is a new view, and figure (b) is a diagram of the crystal piece.

The crystal resonator consists of a crystal piece 1, a container body 2, and a cover 3. The crystal piece 1 is, for example, a rectangular AT-cut, and counter electrodes 5 from which lead electrodes 4 extend are formed at both ends. The container body 2 is mainly a concave laminated ceramic body having a stepped portion, and a weld ring 6 is provided on the upper surface of the side wall. The weld ring 6 is formed by press working (punching). The cover 3 has a thin outer periphery and has a step on the outer periphery. Then, both ends of the crystal blank 1 are fixed and held on the stepped portions. Note that a conductive conductor (not shown) is formed in the stepped portion and extends from the ceramic laminated surface to the outer surface. Then, the outer periphery of the cover 3 is seam-welded to the welding ring 6 to seal it. In the seam welding, a pair of rollers (not shown) are brought into contact with opposing outer peripheral ridgeline portions of the cover 3, respectively. Then, the rollers are rotated and energized to resistance weld first a pair of opposite sides, and then similarly the opposite sides of the base assembly.

(Prior art interlocking point) However, in the above structure, when fixing both ends of the crystal piece 1 to the step part, a conductive adhesive (not shown), which is an organic substance of polymeric resin, is used.

Then, the conductive adhesive generates stress on the crystal blank 1 by solidifying. In addition, after fixation, the stress fluctuates with temperature due to the difference in linear expansion coefficient with the capacitor body 2. In this example, since both ends are fixed, this effect is particularly large, but it is the same even if one end is fixed. There is an influence.

Furthermore, these organic substances have an interlayer that deteriorates aging characteristics such as changing the oscillation frequency due to the generation of gas over time. In addition, generally, an adjustment mask (not shown) is provided in front of the crystal blank 1, and, for example, metal is vapor-deposited on the excitation electrode 5 to adjust the frequency by the mass load effect.Therefore, it is necessary to remove the mask, which reduces productivity. There was also a WIJ.

(Objective of the Invention) An object of the present invention is to provide a crystal resonator for surface mounting that has good aging characteristics and improved productivity.

(Solution Means) The present invention forms a stepped portion on the inner wall of the container body so that one surface on both ends of the crystal piece is brought into contact with the other surface on both ends of the ink piece. The crystal piece is mechanically held by a body, and a through hole for frequency adjustment is provided in the flat elastic body corresponding to the excitation electrode of the crystal piece, and a through hole is provided on the other side of both sides of the crystal piece. The solution is to derive the extracted extraction electrode by bonding. 6 (Example) Figure 111 is a diagram of a crystal oscillator to explain an embodiment of the present invention.
It is an exploded view of 11 parts. Note that the same parts as those in the previous conventional example drawings are given the same numbers and their explanations will be omitted.

As for the crystal mass, place the crystal piece 1 inside the container body 2 in the same manner as described above, and weigh 11g! The cover 3 is joined to the upper surface (welding ring 6) by seam welding. and.

In this embodiment, one surface of the outer periphery of both ends of the crystal piece 1 is brought into contact with the stepped portion. A metallic flat elastic body 8 is interposed between the cover 3 and the other surface of the crystal blank 1 to hold and fix the crystal blank 1 during seam welding. The flat elastic body 8 has legs 9 (abcd) bent from both ends, is processed into an engineering shape (flat), and is further provided with a through hole 10 in the center. and,
The center portion is fixed to the cover 3, and each leg portion 9 is fixed to the four corners of the crystal piece 1. Further, the lead electrodes 4 extending to the outer periphery of both ends on the other side of the crystal piece 1 are electrically conductive by bonding the metal side wires 11. 7.

In such a device, the crystal piece 1 is held and fixed to the stepped portion of the container body 2 using the flat elastic body 8, and the extraction electrode 4 is led out by bonding, so that organic matter can be removed from the inside of the container. In addition, although both @ parts of the crystal piece 1 are fixed to the flat elastic body 8, strictly speaking, both @ parts are in a state of both @7 Lee, so generation of stress due to solidification of adhesive and stress fluctuation due to difference in linear expansion coefficient can be avoided. can. For this reason, aging characteristics such as changes in oscillation frequency over time are made to be good.

In addition, since the flat elastic body 8 also serves as an adjustment mask through which the metal particles (arrow P) pass through through the through holes 9, it is not necessary to remove it after adjustment, which improves productivity.

(Other matters) In the above embodiment, the flat elastic body 8 was explained as having an integral engineering shape (flat), but as shown in FIG. There are various ways to prevent the metal particles from scattering onto the end surface of the crystal piece 1. Although it was explained as a crystal oscillator, for example, an IC chip or the like can be mounted on the bottom of the container body to generate a crystal. It is also possible to configure an III or the like.

(Effects of the Invention) The present invention provides a step part formed on the inner wall of the container body so that one surface on both ends of the crystal piece is brought into contact with the flat plate-shaped part interposed between the cover and the other surface on both ends of the crystal piece. The crystal piece is mechanically held by an elastic body.

A through hole for frequency adjustment was provided in the flat elastic body corresponding to the excitation electrode of the crystal piece, and extraction electrodes extending to the other side of both ends of the crystal piece were led out by bonding. It is possible to provide a crystal resonator for surface mounting that has good characteristics and improved productivity.

[Brief explanation of the drawing]

FIG. 311 is a diagram of a crystal resonator illustrating an embodiment of the present invention, in which FIG. 311 is a cross-sectional view and FIG. 311 is an exploded view of essential parts. 'M2 is a diagram of another embodiment of the present invention, particularly of a flat elastic body. Figures 1 and 3 are diagrams explaining the basic configuration of the conventional example.
) is a sectional view, and FIG. 1(b) is a diagram of a crystal piece.

Claims (1)

[Claims] In a surface mount crystal resonator, a welding ring is provided on the upper surface of a side wall of a container body that accommodates a crystal piece, and a cover for sealing the container body and the welding ring are joined by seam welding. A stepped portion is formed so that one side of both ends of the crystal piece comes into contact with the other side, and a flat elastic body is interposed between the cover and the other side of both ends of the crystal piece to elastically hold the crystal piece. , providing a through hole for frequency adjustment in the flat elastic body corresponding to the excitation electrode of the crystal piece;
A crystal resonator for surface mounting, characterized in that extraction electrodes extending to the other surface of both ends of the crystal piece are led out by bonding.