JPH07105689B2 - Piezoelectric vibrator - Google Patents

Description

TECHNICAL FIELD The present invention relates to a piezoelectric vibrator.

[Conventional technology]

In a conventional piezoelectric vibrator, a fixing method using an adhesive or a fixing method using solder having a Sn: Pb ratio of 6: 4 or 9: 1 was used for fixing the piezoelectric vibrating piece. Further, for the sealing, the press-fitting method using the solder or gold, the welding method and the pressure welding method have been used.

[Problems to be solved by the invention]

However, the above-mentioned conventional technique has a problem that it has a low storage temperature because it lacks heat resistance, a high temperature cannot be applied even during mounting, or is expensive. Therefore, the present invention solves such a problem, and an object of the present invention is to provide a piezoelectric vibrator which is inexpensive and has heat resistance.

[Means for solving problems]

A piezoelectric vibrator of the present invention includes: a piezoelectric vibrating piece; a case for encapsulating the piezoelectric vibrating piece; a lead wire electrically connected to the piezoelectric vibrating piece and plated with high-temperature solder; and holding the lead wire. Also, in a piezoelectric vibrator having a stem that has an annular metal part in the periphery and is press-fitted into the case, when the stem is press-fitted into the case, the case and the metal part are kept airtight. The means is high-temperature solder before being brought into a molten state, and the lead wire and the piezoelectric vibrating piece are joined by the high-temperature solder.

〔Example〕

FIG. 1 is a structural diagram of a crystal oscillator as one embodiment of the piezoelectric oscillator of the present invention. A tuning fork type crystal vibrating piece 1 made by a photolinography from a crystal plate is lead 3 to a metal ring 7.
To the lead 3 of the stem 2 that is sealed with glass, Sn vs. Pb
It is fixed by the high-temperature solder 4 having a melting point of 260 ° C. or higher with a ratio of about 1: 9. At this time, a solder chip is sandwiched between the crystal vibrating piece 1 and the lead 3 and fixed by passing through a high temperature furnace. Further, if the leads 3 are plated with high-temperature solder, the mass productivity is more excellent. The crystal resonator is completed by vacuum-sealing the case 6 having the inner surface plated with the high-temperature solder 5 on the metal ring 7 of the stem 2 to which the crystal vibrating piece 1 is fixed with the high-temperature solder 4 by a press-fitting method.

Since the conventional plating method of the solder on the stem or the case uses the rotary plating method, the solder adheres to the entire metal portion of the stem and the case. For this reason, the solder of the entire metal portion is melted and gas is released, and the gas adheres to the vibrating piece or the degree of vacuum is lowered, thereby deteriorating the characteristics.

However, in the piezoelectric vibrator of the present invention, the high temperature solder is press-fitted without melting and the high temperature solder is adhered only to the portion where the metal ring and the case are in contact with each other, so that no gas is generated. Further, as shown in FIG. 1, the high-temperature solder 4 is the crystal vibrating piece 1.
It is more preferable to carry out partial plating so that the high temperature solder 5 is used only for the fixed portion of the lead 3 and the sealing portion of the stem 2 and the case 6. This is because even if the solder does not melt, some gas is released from the solder inside the case, and Pb
This is because it is liable to be oxidized and the solderability may deteriorate unless flux is used.

FIG. 2 shows a state diagram of solder. The melting point of solder exceeds 260 ° C. when the composition of Sn: Pb ratio in the shaded area is 1: 9 or more. When the amount of Pb is large, not only is the heat resistance improved, but it is stable even at extremely low temperatures. This is because Sn may crack and crack at extremely low temperatures. Since high importance is attached to heat resistance and workability, the solder may be high temperature solder containing not only Sn and Pb but also a third metal such as Ag.

In the case of the above structure, the manufacturing technique is the same as the conventional one, the material is inexpensive, the mass production is possible, and the miniaturization is easy. This is because the process of fixing the piezoelectric vibrating piece tends to be loaded with a load, and the solder melting method facilitates manufacturing. Also, by adopting the press-fitting method as the sealing method, it becomes easy to manufacture with an inexpensive material. Further, since such a press-fit type crystal resonator has no heat resistance, it has not been mounted in the same manner as the recently developed chip parts. However, this press-fitting type heat-resistant crystal oscillator can be mounted simultaneously with a chip component. It was confirmed that the crystal unit did not deteriorate in characteristics at a mounting temperature of 260 ° C and a storage temperature of 150 ° C.

As described above, the tuning fork crystal vibrating piece has been described.However, even if the piezoelectric vibrating piece of other shape such as a rectangular AT-cut quartz vibrating piece and a lithium tantalate vibrating piece made by mechanical outer shape processing is used, the heat resistance is not deteriorated. It was confirmed that there was not.

〔The invention's effect〕

As described above, according to the present invention, by fixing the piezoelectric vibrating piece and the stem with the high-temperature solder, it is possible to obtain the heat resistance capable of being simultaneously mounted with the chip component in the piezoelectric vibrator which is easy to manufacture and inexpensive. . By adopting a press-fitting method using high-temperature solder for sealing, a highly reliable, small-sized and inexpensive piezoelectric vibrator can be obtained.

[Brief description of drawings]

 FIG. 1 is a structural diagram of the piezoelectric vibrator of the present invention. FIG. 2 is a state diagram of solder.

Claims (1)

[Claims] 1. A piezoelectric vibrating piece, a case for encapsulating the piezoelectric vibrating piece, a lead wire electrically connected to the piezoelectric vibrating piece, which is plated with high-temperature solder, and which holds the lead wire and surrounds it. In a piezoelectric vibrator having an annular metal part and a stem press-fitted into the case, a means for keeping the case and the metal part airtight when the stem is press-fitted into the case, A high-temperature solder before being in a molten state, wherein the lead wire and the piezoelectric vibrating piece are joined by the high-temperature solder.