JPS5912805Y2 - Width shear oscillator - Google Patents

Description

[Detailed description of the invention] The present invention relates to a width shear vibrator that generates width shear vibration, and more specifically to a width shear vibrator that has been designed to be smaller in size and to have improved shock resistance and vibration characteristics prior to the width shear vibration. be.

When a predetermined electric field is applied to a resonator such as a crystal resonator, it causes distortion and oscillates at a predetermined frequency. Crystal resonators are classified into DT cut, CT cut 1, AT cut, BT cut, NT cut crystal resonators, etc.

When an appropriate electric field is applied to the crystal resonator cut in this manner, vibrations corresponding to the above-mentioned resonators are generated, such as width shear vibration, contour shear vibration, thickness shear vibration, and bending vibration.

For convenience of explanation, a width shear resonator that causes width shear vibration is taken as an example of a crystal resonator, as shown in Figs. 1 and 2.
For example, the Z-axis (optical axis) perpendicular to the X-axis (electrical axis) of the crystal body is rotated around the X-axis by θ (for example, in the case of Fig. 1, about 3
5° to 52°) and the above-mentioned X-axis, which are parallel to the z'-x plane and facing each other, and the above-mentioned Z-axis and the X-axis are orthogonal to the Z-X plane. The y-axis is rotated by θ with the X-axis as the rotation axis, and the cut planes parallel to the
It can be said that it is formed as a modification of the AT-cut crystal resonator 1X-cut crystal resonator 2, etc., which has opposing cut surfaces parallel to the y'-2' plane constituted by the axis and the 2' axis.

The width-slip crystal resonator 3, which is formed as a modification of the AT-cut crystal resonator 1, is cut along the X-axis and formed into a rectangular shape elongated in the X-axis direction, as shown in FIG. The width-slip crystal oscillator 4, which is formed as a modification of the oscillator 2, is cut along the y-axis and has a rectangular shape elongated in the y'-axis direction, as shown in FIG.

These are sometimes called a type of DT-cut crystal resonator depending on the configuration of their drive electrodes.

The width shear oscillator 3゜4 formed in this way is conventionally 0
．． It is being developed for filters with frequencies of 5 MHz or higher, or for oscillators, but basically, as shown in Figure 3a, the length 1 is 20 to 30 times or more the width W, and the width W is the thickness. It is formed into a rectangular shape with a dimension 2 to 3 times larger than t.

When an electric field is applied via the electrodes 6, 6 to the pair of cut surfaces 5, 5 perpendicular to the thickness t direction, the width-slip crystal oscillators 3, 4 undergo width-slip as shown by the arrows b in FIG. This causes distortion, causing main vibration A that vibrates at a predetermined frequency (resonant frequency) as shown in FIG. 4, and a large number of spurious vibrations B that vibrate at frequencies other than the predetermined frequency.

The main vibration of the width shear vibrator is obtained by the width shear strain described above, and its resonant frequency fo is mainly determined by the dimension of the width W.

The conventionally proposed width shear oscillator 7 is formed into a plano bevel shape that is tapered so that the width at both ends becomes narrow, as shown in FIG. Chain points 8°9 are provided for support.

The width shear vibrator 7 is supported via support handles 10 and 11 fixed to the chain points 8 and 9 with solder, conductive adhesive, etc. The vibration constrained area at the end is the chain point 8,
9. Since it becomes large due to soldering, etc., the Q value tends to decrease and vibration characteristics tend to deteriorate.

In addition, since the vibration constraint area is large, the support handles 10, 11
has a large influence on the above-mentioned Q value and vibration characteristics, so the influence of the support is reduced by making the length 1 of the width shear vibration 7 sufficiently larger than the width W, and also by making the support handle 10.11 thinner or longer. Although it is necessary to weaken the support strength by increasing the length and reduce the influence on vibration characteristics, the support handle 10
If the support strength of .
At a relatively low frequency such as ~1.5 MH2 (7), it has the defect that the vibrator size becomes too large.

Therefore, it has been difficult to use it as an oscillator inside a small portable electronic device such as an electronic wristwatch.

This invention eliminates the above-mentioned conventional defects, reduces the vibration binding area, increases the Q value of the vibrator, and improves the vibration characteristics, and can also be used in small portable electronic devices such as electronic wristwatches. This paper proposes a compact width-shear oscillator that can perform

Hereinafter, the present invention will be explained in detail with reference to the illustrated embodiments.

FIG. 6 shows an embodiment of a width-shear oscillator according to the present invention, and reference numeral 12 indicates a oscillator body of the width-shear oscillator.

The vibrator main body 12 has a shape that allows width-shear vibration to occur efficiently even when downsized, for example, the length l is at least 10 times the width W□-E
, is formed in a plano-convex shape so that the width W1 is 2 to 5 times the thickness t, and the width W2 at both ends in the length direction is narrower than the width W1.

Electrodes 14.14 are formed on a pair of cut surfaces 13.13 perpendicular to the thickness direction of the vibrator body 12 by means such as vapor deposition or sputtering.

The electrode 14 is composed of a main electrode 15 formed approximately at the center of the vibrator body 12, and extraction electrodes 16 extending from the main electrode 15 to the longitudinal ends of the vibrator body 12, respectively.

Width W2 near both longitudinal ends of the vibrator body 12
At approximately the center of the electrode 14, holes 17 and 18 are machined to penetrate through the part of the electrode 14 where the extraction electrode 16 is formed.

The holes 17, 18 are formed by etching or the like, but they can also be machined using a drill or the like.

Linear support handles 19.20 made of a conductive elastic material are attached to holes 17.18 as processed parts provided near both longitudinal ends of the vibrator main body 12, and the above-mentioned electrodes It is electrically connected to the 14 lead electrodes 16 via solder or the like.

Therefore, the vibrator main body 12 has the support handle 19.2.
0 and is electrically connected to the electrode 14.

In this way, holes 17.18 are provided near both ends of the vibrator body 12 in the length direction, and the support handles 19.20 attached to these holes 17.18 are used to connect the vibrator body 12.
Q
To obtain sufficient vibration characteristics for use in a high-precision electronic wristwatch even if the length l of a vibrator main body 12 is significantly reduced compared to the conventional one, by increasing the vibration characteristics of width shear vibration. At the same time, the support handles 19 and 20 can be firmly fixed to the holes 17 and 18 serving as the processed portions, and even if the rigidity of the support handles 19 and 20 is weakened, there is no possibility that the support handles 19 and 20 will separate from the holes 17 and 18. It is possible to obtain a width shear vibrator with no leakage and high impact resistance.

In addition, the vibrator body 12 has holes 17.18 as processed parts, and the support handle 19.20 is attached to the hole 17.18, so the workability is good and the vibration restraint area can be made uniform even in mass production. A width-shear resonator with uniform vibration characteristics can be obtained.

With this configuration, the width shear oscillator can be made compact, and the oscillator used in small portable electronic devices such as electronic wristwatches can be easily miniaturized without deteriorating the performance. can.

FIG. 7 shows another embodiment of the width-shear transducer according to the present invention. The difference from the above-mentioned embodiment is that both longitudinal ends of the transducer body 21 are tapered from both sides. While cutting, the width W3 near the end in the length direction
A rectangular shaped concave portion 22 serving as a processed portion is formed approximately in the center of the .
23 is formed by means such as etching.

An elongated support handle 24.25 in the shape of a square rod is attached to the recessed portion 22.23 serving as the processed portion.

By bevel-cutting both lengthwise ends of the vibrator body 21 in this manner, vibrations at the lengthwise ends of the vibrator body 21 can be damped more effectively, and the support handles 24 and 25 It is possible to reduce the negative influence on the vibration characteristics due to the support, and it becomes easy to improve the Q value and the vibration characteristics.

FIG. 8 shows still another embodiment of the width-shear oscillator according to the present invention. The difference from the above-mentioned embodiment is that the width of the oscillator body 26 is gradually changed in an arc shape in the longitudinal direction. The second point is that the processed portions provided at both ends of the vibrator body 26 are formed into grooves 27 and 28 parallel to the length direction.

The grooves 27 and 28 as the processed parts are machined using a cutter or the like, and in the case of mass production, a large number of vibrator bodies 26 are overlapped and grooves are formed in a large number of vibrator bodies 26 in one machining process. 27.28 can be formed.

The grooves 27.28 as the processed portions include the grooves 27.2 and 27.28.
A support handle 29,30 formed in a plate shape conforming to the size of the 8 is attached.

With this configuration, the grooves 27 and 28 as processed parts
can be processed uniformly and easily, and manufacturing costs can be reduced.

Furthermore, by forming the support handles 29 and 30 in a plate shape, the impact resistance, especially the impact resistance in the twisting direction, can be significantly improved.

Although the details of the present invention have been explained above with reference to the illustrated embodiments, the present invention is not limited to the illustrated embodiments, and the shape of the vibrator body and the processed portion formed on the vibrator body. It is possible to make various changes and improvements, such as the possibility of making various changes, and furthermore, the vibrator main body can be made of a piezoelectric crystal such as tantalate or niobate.

As described above, the width-slip vibrator according to the present invention has processed parts near both ends in the length direction of the vibrator body, which is formed to have a sufficiently long length relative to its width and a width greater than its thickness. By supporting the vibrator via the support handle attached to the processed part, it is possible to reduce the vibration restraint area caused by the support on the surface of the vibrator body, increase the Q value, and improve the vibration characteristics of width shear vibration. Can be downsized,
Furthermore, the support handle can be easily and firmly fixed to the processing part, improving workability and facilitating mass production, as well as improving impact resistance, making it compact and vibration-resistant. It is possible to construct an oscillator with high characteristics and can be widely used in small portable electronic devices such as electronic wristwatches, and it can fully achieve the intended purpose and has great practical effects. have

[Brief explanation of the drawing]

Figures 1 and 2 are perspective views showing generally used width-shear resonators in correspondence with AT-cut crystal resonators and X-cut crystal resonators, and Figure 3 is a width-shear resonator that causes width-shear vibration. In this figure, a is a perspective view,
Fig. 4 is a diagram showing the frequency spectrum near the resonance point of the width-shear oscillator; Fig. 5 is a perspective view of a conventional width-shear oscillator; FIG. 6 is a perspective view showing one embodiment of the width shear oscillator according to the present invention, FIG. 7 is a perspective view showing another embodiment of the same width shear oscillator, and FIG. 8 is a perspective view showing another embodiment of the same width shear oscillator. FIG. 7 is a perspective view showing another embodiment. 3, 4. 7... Conventional width shear oscillator, 12.2
1゜26... Vibrator body of width-slip vibrator, 14...
・Electrode, 17°18... Hole as processing part, 19.2
0.24. Fathom -29,30...Support handle attached to the processed part, 22;-23...Recessed part as a processed part, 2
7.28...Groove as a processed part, l...Length of the vibrator body, W...Width of the vibrator body, t...Thickness of the vibrator body.

Claims (1)

[Scope of utility model registration request] In a width shear vibrator that is formed to be sufficiently long in length relative to its width and wider than its thickness, there is a groove formed approximately at the center of the width near both ends in the length direction, and a groove within this groove. A width-slip oscillator characterized by comprising a support handle provided in the width-slip oscillator.