JPH0522072A - Tuning fork type torsional crystal oscillator - Google Patents

Abstract

PURPOSE:To reduce equalizing serial resistance by arranging the tuning fork type torsional crystal oscillator on an etching surface so that an electrode faced to the oscillation part of a tuning fork arm can be different polarity from an adjacent electrode. CONSTITUTION:An excitation electrode 4 arranged on the etching surface as the side face of an oscillation part 2 as one tuning fork arm is connected through a connecting electrode 12 to an excitation electrode 7. Further, the excitation electrode 7 is connected through a connecting electrode, which is arranged on the lower surface of an oscillator 1, to excited electrodes 9 and 10 and finally connected to a terminal electrode 15. Completely similarly, an excitation electrode 11 arranged on the etching surface as the different pole is connected through a connecting electrode 13 to an excitation electrode 8, and the excitation electrode 8 is connected through an electrode, which is arranged on the surface of the oscillator 1, to a terminal electrode 14 and simultaneously connected to an excited electrode 5 as well. Thus, two temrinal electrodes are formed by the terminal electrodes 14 and 15. Therefore, by impressing an alternate voltage between both these temrinals, torsional oscillation can easily generate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excitation electrode structure of a tuning fork-shaped torsional quartz crystal resonator in which a plurality of vibrating portions and a supporting portion are integrally formed by a chemical etching method. In particular, wristwatches that are highly demanded for downsizing, high precision, impact resistance, and low cost,
The present invention relates to a tuning fork type twisted crystal oscillator which is most suitable as a reference signal source for pagers, IC cards, mobile radios and the like.

[0002]

2. Description of the Related Art In a conventional tuning-fork crystal oscillator, since the oscillator forming method by machining is adopted, the excitation electrodes are arranged on both upper and lower surfaces of the vibrating arm. Moreover, the upper and lower electrodes were divided so that a parallel electric field was applied.

[0003]

However, in the conventional excitation electrode arrangement method, since the effective component of the electric field is brought by the parallel electric field, the electric field efficiency is poor and the equivalent series resistance R _{1 of the} vibrator becomes large, so that Q There remains a very important problem such as a decrease in the value and a large current consumption in the oscillation circuit. Therefore, a new method of arranging the excitation electrodes, which has a smaller electric field efficiency and can make R ₁ smaller, has been desired.

[0004]

The present invention solves the conventional problems by the following methods. That is, a tuning-fork-shaped twisted quartz crystal oscillator having a plurality of vibrating arms and a vibrating portion and a supporting portion formed integrally by a chemical etching method, and an electrode facing or facing an etching surface of the vibrating portion. The problem is solved by arranging an excitation electrode in which adjacent electrodes have different polarities.

[0005]

By arranging the excitation electrodes in this way, the electric field components of the opposing electrodes become vertical, so that the electric field efficiency is improved, and as a result, the twisted quartz vibration with a small equivalent series resistance R ₁ and a high Q value I have a child.

[0006]

EXAMPLES Next, the present invention will be specifically described based on Examples. 1A and 1B are a schematic view (a) and a cross-sectional view (b) of the xz plane showing an embodiment of the tuning fork type twisted crystal oscillator of the present invention and its excitation electrode arrangement. The vibrator 1 includes excitation electrodes 4, 5, 6,
It is composed of a vibrating portion 2 having 7, 8, 9, 10, 11 and connecting electrodes 12, 13 and a supporting portion 3 having terminal electrodes 14, 15. In particular, the excitation electrodes 4 and 6, 5 and 7, 8 and 1
0, 9 and 11 are arranged so as to face the vibrating portion 2. On the other hand, the excitation electrodes 4 and 5, 6 and 7, 8 and 9, 1
0 and 11 are arranged so as to be adjacent to each other. The tuning fork type torsion oscillator of the present invention is formed by a chemical etching method. The excitation electrode 4 arranged on the etching surface of the side surface of the vibrating portion 2 which is one tuning fork arm is connected to the excitation electrode 7 via the connection electrode 12.

Further, the excitation electrode 7 is connected to the excitation electrodes 9 and 10 and finally to the terminal electrode 15 via a connection electrode arranged on the lower surface (not shown) of the vibrator 1. Exciting electrodes 11 arranged on the etching surfaces having opposite polarities are connected to exciting electrodes 8 via connecting electrodes 13. Further, the excitation electrode 8 is connected to the terminal electrode 14 via the electrode arranged on the upper surface of the vibrator 1, and at the same time, further connected to the excitation electrode 5. Therefore, the terminal electrode 14
And 15 form a two-terminal electrode. By applying an alternating voltage between the two terminals, torsional vibration can be easily caused.

By constructing the excitation electrode in the tuning fork shape as described above, the equivalent series resistance R ₁ can be reduced and the vibration energy can be confined inside the vibrating portion of the tuning fork arm. A tuning fork type twisted crystal oscillator is obtained. Although the tuning fork shape having two arms has been described in the embodiment of the present invention, even in the tuning fork shape having three or more arms, the object of the present invention can be achieved by disposing the adjacent electrodes in different polarities. It goes without saying that you can do it. Further, in the present embodiment, the case where four counter electrodes are provided for the tuning fork arm has been described, but the object of the present invention can be achieved if at least one counter electrode is provided.

[0009]

As described above, the present invention has the following remarkable effects by proposing a tuning fork type twisted crystal oscillator having a tuning fork shape and a new excitation electrode configuration. (1) Since the excitation electrodes are arranged so that the excitation electrode facing the tuning fork arm and the adjacent excitation electrode have different polarities on the etching surface on the side surface of the tuning fork vibrating portion, excellent electric field efficiency and equivalent series The resistance R ₁ is small and the Q value is high. (2) Since this oscillator is integrally formed by the etching method, it can be made compact and thin. (3) Since it is mounted on a lead wire or the like on one side, it can be manufactured easily and at low cost. (4) Since it has a tuning fork shape, it is possible to obtain a twisted quartz oscillator without vibration leakage. Therefore, a vibrator having a small R ₁ can be obtained even if it is supported and fixed to the lead wire or the like by the mount portion.

[Brief description of drawings]

FIG. 1 is a schematic view (a) and a cross-sectional view (b) of an xz plane of an embodiment of an excitation electrode arrangement of a tuning fork type twisted crystal oscillator of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 vibrator 2 vibrating part 3 support part 4-11 excitation electrode 12, 13 connection electrode 14, 15 terminal electrode x electrical axis y mechanical axis z optical axis

Claims (1)

Claim: What is claimed is: 1. A tuning fork-shaped twisted quartz resonator having a plurality of vibrating arms, wherein a vibrating portion and a supporting portion are integrally formed by a chemical etching method. A tuning-fork type twisted quartz crystal resonator, in which an opposing electrode or an exciting electrode in which an opposing electrode and an electrode adjacent to the opposing electrode have different polarities is arranged.