JPH04213910A - Contour-shear crystal vibrator - Google Patents

Abstract

PURPOSE:To realize the vibrator with high frequency and less spurious radiation by forming the vibrator integrally with the etching method and forming a vibration part to be cylindrical. CONSTITUTION:A vibration part 2 is formed cylindrical and a bridge 3 is provided to two positions at different ends of the part 2 symmetrically and a projection 5 is led from the bridge 3 via a buffer having a hole 8. The projection 5 is fixed and supported. Each part is formed integrally and lots of vibrators are simultaneously formed from a crystal plate by the etching. Then an exciting electrode 6(7) is arranged to an upper (lower) face of the cylindrical vibration part 2 and contour-shear vibration is easily caused by impressing an alternate voltage between both the electrodes.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the shape of a contour sliding quartz crystal resonator in which a vibrating part and a supporting part are integrally formed by chemical etching. In particular, the present invention relates to a contour-slip crystal resonator that is optimal as a reference signal source for portable devices such as IC cards, pagers, and mobile radios, which have strong demands for ultra-thin and compact design.

0002

2. Description of the Related Art Conventional contour slip quartz crystal resonators are generally machined and have a square shape. The plate is supported and fixed by two opposing lead wires at the center of the plate. Therefore, the frequency of the vibrator made in this way was about 600 KHz at the highest. In addition, in order to increase the frequency and reduce the size, the inventor proposed and put into practical use a contour slip quartz crystal resonator in which a supporting part is added to a square vibrating part and integrally formed by an etching method. Judging from the frequency constant, at most 4MH
The frequency of z was the limit.

0003

[Problems to be Solved by the Invention] In the conventional machining method, when trying to downsize and increase the frequency, vibration energy loss due to the support points increases, and at high frequencies, R1 becomes large, making it insufficient for use as a vibrator. was unable to perform its functions. On the other hand, the vibrating part has a square shape,
The vibrator, which is formed integrally with the support part by an etching method, has a frequency constant of approximately 320 KHz・Cm (cut angle θ≒
37 degrees, and in order to obtain a frequency of 4 MHz or more, it is necessary to significantly reduce the area of the vibrating part. This is R1
This will inevitably lead to an increase in Therefore, in order to increase the frequency and obtain a vibrator with a small R1, it is naturally necessary to have a vibrating part shape with a large frequency constant.

0004

SUMMARY OF THE INVENTION Accordingly, the present invention solves the conventional problems in the following manner. That is, in a contour slip quartz crystal resonator that consists of a vibrating part and a support part and is integrally formed by an etching method, the support part is provided symmetrically to the vibrating part via a bridge part, and a hole can be formed in the support part. The object of the present invention is achieved by configuring the vibrator to be composed of a frame and a protruding portion that go around the same time, and the vibrating portion to have a circular shape.

[0005]

[Operation] As described above, the contour slip crystal resonator of the present invention has
It consists of a circular vibrating part, a bridge part, a frame that goes around the whole circle, and a protruding part. In particular, since the vibrating part has a circular shape, the frequency constant is larger than that of a square shape, approximately 385K.
Hz·Cm (cut angle θ≒37°). Therefore, if the frequency is the same, a circular shape can have a larger area, and R
A contour-slip crystal resonator with a small and high Q value of 1 is obtained.

[0006]

EXAMPLES Next, the present invention will be specifically explained based on examples. FIG. 1 is a plan view (a) and a side view (b) of an example of the shape and excitation electrode arrangement of the contour slip quartz crystal resonator of the present invention.
shows. The vibrator 1 is connected to a frame 4 that goes around the circular vibrating part 2 and the bridge part 3 so that a hole 8 is provided therein, and a protruding part 5 that is connected to this frame and fixed to other lead wires, a pedestal, etc. It is configured. This complexly shaped vibrator is integrally formed by chemical etching. Further, excitation electrodes 6 and 7 are arranged on the upper and lower surfaces of the circular vibrating section 2, and by applying an alternating voltage between the two electrodes, contour sliding vibration can be easily caused. In FIG. 1, the excitation electrode is arranged in a part of the vibrating section 2, and its size is optimally determined in order to avoid spurious vibrations that depend on the frequency and plate thickness. Usually 50%
~85% of the electrodes are suitable as oscillators. Of course, it goes without saying that if the excitation electrode is provided on the entire surface of the vibrating section 2, a small R1 can be obtained. Also, by making the vibrating part 2 circular, when the cut angle θ (the angle when the Y plate is rotated around the x-axis) is 37°, the frequency constant is approximately 38.
An experimental value of 5KHz・Cm was obtained, whereas the conventional square shape has a larger value of about 320KHz・Cm, which is about 16.9% larger for the circular shape.If the frequency is the same, the circular shape naturally has a longer side length. can be made larger. In other words, the effective area for generating distortion becomes larger, and R1 can be reduced. Next, let's talk about vibration leakage. This vibrator is provided symmetrically at both ends of a circular vibrating part 2, and has a bridge part 3.
The buffer section is formed by the frame 4 that goes around the frame 4 so as to form a hole 8 through the hole 8, and is further composed of a protrusion 5, so that the vibration energy of the vibrating section 2 is transferred to the protrusion 5 that is supported and fixed.
It doesn't get across at all. Therefore, good characteristics can be obtained without causing deterioration of the equivalent series resistance R1.

[0007]

As described above, the present invention has the following significant effects by proposing a new contour slip crystal resonator having a circular vibrating section. - Since the vibrating section is circular, the frequency constant is larger than that of a square vibrating section, making it possible to obtain a contour-slip crystal resonator with a higher frequency.

[0008] By additionally connecting the support section composed of the bridge section, the frame and the protruding section to the circular vibrating section, it becomes easy to support and fix the support section to an external terminal such as a lead wire or a pedestal. As a result, a contour slip crystal resonator having no vibration leakage, a small equivalent series resistance R1, and a high Q value is obtained. - Since the vibrating part and the support part of this vibrator are integrally molded using a chemical etching method, it is possible to make the vibrator smaller and thinner.

(2) Since the vibrating section has a circular shape, spurious vibrations such as thickness bending vibrations that depend on the thickness can be easily removed. ■ Excellent shock resistance as the vibrator is supported and fixed at both ends.

[Brief explanation of the drawing]

FIG. 1 shows a plan view (a) and a side view (b) of an example of the shape and excitation electrode arrangement of a contour slip quartz crystal resonator according to the present invention.

[Explanation of symbols]

1. Oscillator 2 Vibration part 3 Bridge part 4 Frame 5 Protruding part 6, 7 Excitation electrode 8 holes

Claims (1)

[Claims] Claim 1: In a contour slip quartz crystal resonator consisting of a vibrating part and a support part, which are integrally formed by an etching method, the support part is provided symmetrically to the vibrating part via a bridge part, and the support part has a hole. What is claimed is: 1. A contour slip quartz crystal resonator, characterized in that it is composed of a frame and a protruding part that go around the same time so as to form a circular frame, and that the vibrating part has a circular shape.