JPH0435513A - Surface mounting crystal resonator - Google Patents

Abstract

PURPOSE:To make the time aging characteristic satisfactory and to improve the workability by allowing both end outer peripheral parts of one face side in which a leader electrode of crystal piece is extended out to abut on a stepped part, interposing an elastic body between a cover and the other face of both end sides of the crystal piece and holding mechanically the crystal piece. CONSTITUTION:One face of both end outside peripheral part of a crystal piece 1 is allowed to abut on a stepped part, and between a cover 3 and the other face side of the crystal piece 1, a metallic elastic plate 8 is interposed. The elastic plate 8 is worked in a shape, its center part is joined in advance to the cover 3, and each leg part 9a - 9d abuts on leader four corner parts of the crystal piece 1. In this regard, it does not come into contact with a leader electrode. In such a state, at the time of seam welding of the cover 3, the crystal piece 1 is pressed by the elastic plate 8, and held and fixed. Simultaneously, a conductive line 7 of the stepped part and the leader electrode 4 extended out to both end outer peripheral parts of the other face side of the crystal piece 1 are connected elastically and allowed to conduct. In such a way, the time aging characteristic becomes satisfactory and the workability can be im proved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention is applied to a crystal resonator for surface mounting, and relates to a crystal resonator with good aging characteristics and good workability.

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 2 is a diagram explaining the basic configuration of such a conventional example.
FIG. 5(a) is a cross-sectional view, and FIG. 1(b) is a diagram of a crystal piece.

The crystal oscillator is an ink piece 1. It consists of a container body 2 and a cover 3. The crystal blank 1 is, for example, a rectangular AT cut, and counter electrodes 5 from which lead electrodes 4 extend are formed on both ends of the crystal blank 1 . 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 path 7 (not shown) is formed in the stepped portion and extends from the laminated surface of the ceramic 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 wire.

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

Then, when the conductive adhesive solidifies, it generates stress on the crystal piece. In addition, after the fixation, the container body 2
Due to the difference between the coefficient of linear expansion and the coefficient of linear expansion, the stress changes with temperature. This effect is particularly large when both ends are fixed. Furthermore, these organic substances cause the generation of gas over time, which causes a problem of deteriorating aging characteristics such as changing the oscillation frequency. Also, crystal piece 1
The work of fixing the material to the step part using a conductive adhesive is troublesome and has the problem of reducing workability.

(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 improves workability.

(Solution Means) The present invention provides a stepped portion on the inner wall of the container body to form a conductive path extending to the outer surface, and applies the outer peripheral portions of both ends of one side of the extending electrode of the crystal piece to the stepped portion. The crystal piece is mechanically held by interposing an elastic body between the cover and the other surface on both ends of the crystal piece, and the conductive path and the extraction electrode are electrically connected. These will be specifically explained using the following examples.

(Example) Figure 111 is a diagram of a crystal resonator for explaining an example of the present invention, where (,) is a new view, and rM (b) is an exploded view of the main 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.

The crystal resonator is constructed by mounting a crystal piece 1 inside a container body 2 and joining a cover 3 to the upper surface of the side wall (welding ring 6) by seam welding, as described above. and.

In this embodiment, one surface of the outer periphery of both ends of the crystal blank l is brought into contact with the stepped portion. A metallic elastic plate 8 is interposed between the cover 3 and the other side of the ink piece 1.

The elastic plate 8 is processed into an engineering shape (flat), and its center part is joined to the cover 3 in advance, and each leg part 9 (abed) is attached to the crystal piece 1.
It touches the four corners of the drawer. However, it does not come into contact with the extraction electrode. Then, when the cover 3 is seam welded, the crystal piece 1 is pressed by the elastic plate 8 to be held and fixed. At the same time, the conductive path 7 of the stepped portion and the extraction electrodes 4 extending to the outer periphery of both ends on the other side of the crystal piece l are also elastically connected to ensure continuity.

In such a device, since the crystal piece 1 is held and fixed to the stepped portion of the container body 2 using the elastic plate 8, organic matter can be removed from the inside of the container. Strictly speaking, both ends of the crystal blank 1 are in a free state, so that stress generation due to the assimilation of the conductive adhesive or the difference in linear expansion coefficients is avoided. therefore,
Prevents deterioration of aging characteristics such as changing the oscillation station wave number.

Furthermore, since the single elastic plate 8 also serves as an electrical connection to the conductive path 7, it is possible to eliminate electrical and mechanical bonding steps and improve workability.

(Other Matters) In the above embodiment, the elastic plate 8 has been described as having an integral engineering shape (plane), but the present invention is not limited to this, and separate elastic bodies may be used at both ends of the crystal piece. Further, it does not necessarily need to be joined to the cover 3, and it is sufficient if the positioning is sufficient. Further, a through hole (not shown) for frequency adjustment may be provided in the center of one elastic plate 8 to further improve workability, and there are various embodiments. Also, crystal piece 1. of-
Although the outer periphery of both ends on the surface side is brought into direct contact with the stepped portion, for example, a plate spring or the like (not shown) may be provided on the stepped portion. Although the explanation has been made as a crystal resonator, for example, an IC chip or the like may be mounted on the lower part of the container body to constitute a crystal oscillator or the like.

(Effects of the Invention) The present invention provides a stepped portion on the inner wall of the container body to form a conductive path extending to the outer surface, and connects the outer periphery of both ends of the extending electrode of the crystal piece to the stepped portion. The crystal piece is mechanically held by interposing an elastic body between the cover and the other surface on both sides of the crystal piece, and the conductive path and the extraction electrode are electrically connected. , it is possible to provide a crystal resonator for surface mounting that has good aging characteristics and improves workability.

[Brief explanation of drawings]

FIG. 1 is a diagram of a crystal resonator illustrating an embodiment of the present invention, with FIG. 1(a) being a sectional view and FIG. 1(b) being an exploded view of essential parts. Figure 2 is a diagram explaining the basic configuration of the conventional example;
is a cross-sectional view, and the same figure (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 step is provided to form a conductive path extending to the outer surface, and the outer periphery of both ends of the extending electrode of the crystal piece is brought into contact with the step, and the outer periphery of the both ends of the cover and the crystal piece is brought into contact with the step. A crystal resonator for surface mounting, characterized in that the crystal piece is mechanically held by interposing an elastic body between it and the other surface, and the conductive path and the extraction electrode are electrically connected.