JPS62194720A - Contour shear crystal resonator - Google Patents

Abstract

PURPOSE:To realize a crystal resonator excellent in the linearity in the frequency temperature characteristic by selecting optimizingly a cut angle theta of a contour shear crystal resonator. CONSTITUTION:An exciting electrode 2 is arranged at upper and lower faces of a diaphragm 5 of a crystal 1. The diaphragm 5 of the crystal 1 is connected with a support 3 via a connection part 4 and they are formed incorporatedly by chemical etching. The electrode 2 is formed only to one side of the left side support 3 and the electrode 2 is arranged to the right side support 3 only at the face opposed to the said left support. A board formed by rotating the Y plate by 46-53 deg. around the X axis is used as the diaphragm 5. Thus, the crystal resonator excellent in the shock resistance and the linearity in the frequency temperature characteristic with small size is realized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a temperature sensor contour slip crystal oscillator used as a temperature sensor to measure temperature. In particular, it relates to the cutting angle and shape of a contour slip crystal resonator that has excellent linearity with respect to frequency and temperature.

[Summary of the invention]

When a contour slip quartz crystal resonator is used as a temperature sensor for temperature measurement, the present invention provides an optimum cutting angle of the resonator that allows temperature measurement to be performed with high precision over a wide temperature range;
The object of the present invention is to provide a contour-slip crystal resonator with a new shape that is compact, has excellent impact resistance, and has low power consumption.

[Conventional technology]

Temperature measurement is the basis of all physical measurements,
Various methods have been proposed and put into practical use. In general, there is a thermocouple method, which is simple in structure and easy to measure, and is the most commonly used method.

[Problem that the invention seeks to solve]

However, recently, there has been a demand for devices to be smaller, consume less power, and be lighter in weight, as well as to be able to measure temperature over a wider temperature range and with higher precision. The thermocouple method described above has a voltage-temperature characteristic where the voltage per 1° C. is small, that is, the sensitivity is poor, so there is a limit to the accuracy of temperature measurement. Furthermore, it is extremely difficult to accurately measure temperature with one thermocouple over a wide temperature range from the low temperature side to the high temperature side. As described above, the reality is that the conventional thermocouple system cannot fully meet recent demands. In addition, temperature sensors using thickness-shear vibration mode have been proposed, but they have drawbacks such as high frequency, high power consumption, and large vibrator size, making them susceptible to shock (and difficult to support methods). .Therefore,
The present invention proposes a new sensor for temperature measurement that improves the above-mentioned drawbacks, and in particular provides a contour slip crystal resonator with a relatively low frequency of around 2 MHz. In other words, it is small, has excellent shock resistance, and reliability.
The present invention provides a contour slip quartz crystal resonator for temperature measurement that has a high-accuracy body side and consumes low power.

[Means for solving problems]

FIG. 1 shows an embodiment of the profile slip crystal oscillator shape of the present invention. Excitation electrodes 2 are arranged on the upper and lower surfaces of the vibrating section 5 of the crystal 1, and the vibrator is excited by these electrodes. Also, crystal l
The vibrating part 5 is connected to the support part 3 through the connecting part 4 and is integrally formed by chemical etching. FIG. 1 shows a case in which both end support parts are connected at one point at the base 6.

The base 6 is connected to a lead wire (not shown) for taking out the electrode. At this time, the electrodes are configured so that no electric field acts on the support portion 3.

More specifically, one of the excitation electrodes 2 is arranged to extend to one support part, and the other electrode 2 extends to the other support part. Then, so that the electric field does not work in the support part 3,
The electrodes are configured. FIG. 2 also shows another embodiment of the profile slip quartz crystal resonator shape of the present invention. The vibrator is composed of a vibrating part and a support part like the vibrator shown in FIG. 1, and the electrodes 2 arranged on the vibrating part 5 are arranged in exactly the same way as in FIG.

Furthermore, one of the electrodes 2 is arranged to extend to one support, and the other electrode 2 extends to the other support. The electrodes are constructed in the same manner as shown in FIG. 1 so that no electric field is applied to the support portion 3.

However, in the embodiment shown in FIG. 2, the shape of the support part 3 is slightly different, and the support part 3 is provided with a mount part 7, which is mounted at both ends on a pedestal made of ceramic or the like.

Furthermore, the x, y', and Z' axes in FIGS. 1 and 2 indicate the electrical, mechanical, and optical axes of the crystal after coordinate rotation.

In this way, by integrally forming the vibrating part and the support part, the impact resistance is improved and the size is reduced, and at the same time, when the width and length of the vibrating part of the vibrator are approximately 1.56 mm, the frequency increases. The frequency is about 2 MHz, which is low, making it possible to reduce power consumption. In FIGS. 1 and 2, the shape of the excitation electrode is circular, but it goes without saying that even if the electrode is placed on the surface of the vibrating section, excellent electrical characteristics can be obtained as in the case of circular a.

Next, frequency temperature characteristics will be explained. Theoretical analysis was performed on a rectangular plate. FIG. 5 shows the coordinate system and cutting method of the vibrator of the present invention. That is, the width W and length e of the crystal plate 8 are the Z axis,
The plate thickness is taken in the X-axis direction and perpendicular to the Y-axis.

Then, the frequency equation of the rectangular plate is approximately given by the following equation.

Here, ρ is the density of the crystal, SzS is the elastic compliance after coordinate rotation, m and n are constants determined by the vibration order, and in the case of the fundamental wave, m = n-1. Since it is a function of
The next temperature coefficient β can be determined as a function of the cut angle θ. Figure 3 shows the calculation results and experimental values.The horizontal axis shows the cut angle θ and the vertical axis shows α and β.The solid line is the calculated value.
0 and x marks are experimental values. According to this calculation, the cut angle θ for β = 0 is approximately 47.9' in the calculated value and approximately 4 in the experimental value.
7.5 @, and α at this time is 55.0p each.
pm/'C and 40.59 pm/'C. Therefore,
Through calculations and experiments, we were able to develop a temperature sensor with excellent linearity.

The contour slip crystal oscillator with linearity of the present invention has θ=4
7.5" is the best, but in reality β varies, β-
〇 is preferable, but in the present invention, in order to obtain a vibrator with sufficient linearity, including the variation in β, the force and throat angle should be 46″.
' to 53'' is sufficient. Fig. 4 shows an embodiment of the contour slip crystal resonator of the present invention. The width W and length l of the resonator are each 1.56 mm, and the cut angle θ is 50 mm. In this example, α was approximately 509I)I11/'C. As is clear from FIG. 3, it was possible to obtain a contour-slip crystal resonator with excellent linearity over a wide temperature range.

[Effect]

In this way, the present invention improves the frequency-temperature characteristics by optimally selecting the cut angle θ of the contour-slip crystal resonator.
This provides a temperature sensor with excellent linearity. As a result, highly accurate temperature measurement is possible over a wide temperature range. At the same time, the new shape of the contour slip crystal resonator is compact and has excellent shock resistance, making it ideal for small devices.

〔Example〕

Embodiments of the present invention will be described below based on the drawings. 1st
The figure shows an example of the shape of the contour slip crystal resonator of the present invention. The vibrator has two supporting parts in the X-axis direction, and the length l (not shown) of the vibrating part and the width direction are provided so as to coincide with the Z'-axis direction. Excitation electrodes 2 are arranged on the upper and lower surfaces of the vibrating part 5 of the crystal 1, and each electrode extends in the direction of a different support part. Vibration can be easily caused by applying an alternating voltage between these two electrodes. Further, the vibrating portion 5 of the crystal 1 is integrally formed with the supporting portion 3 via the connecting portion 4. Furthermore, both end support parts 3 are connected at a central base part 6. On the other hand, FIG. 2 shows another embodiment of the present invention, in which supporting parts 3 are connected to both ends of a vibrating part 5 via connecting parts 4. Furthermore, the support part is provided with a mount part 7, and is fixed to the pedestal here. Figure 4 shows that the width and length of the contour slip crystal resonator of the present invention are 1, 56+1Jl, and θ=
This is an example of frequency temperature characteristics when the temperature is 50.

〔Effect of the invention〕

As described above, the present invention proposes a new shape for the contour slip crystal resonator, and has the advantage that it is small and has excellent impact resistance, and also has low power consumption due to its low frequency. In addition, by optimally selecting the cutting angle of the resonator, it is possible to obtain a crystal temperature sensor with excellent linearity over a wide temperature range between the frequency and temperature characteristics, making it possible to perform highly accurate temperature measurement over a wide temperature range. has.

[Brief explanation of drawings]

FIG. 1 is a side view and a plan view showing one embodiment of the contour slipping crystal resonator shape and electrode arrangement of the present invention, and FIG. The side view and plan view shown in FIG.
FIG. 4 is a diagram showing an example of the frequency-temperature characteristics of the contour slip crystal resonator of the present invention, and FIG. 5 is a diagram showing the coordinate system and cutting method of the resonator of the present invention. FIG. 1...Crystal 2...Excitation electrode 3...Support part 4...Connection part 5...Vibration part 6...Base 7...Mount part and above Applicant Seiko Electronic Components Co., Ltd. Collection 1 Figure 2 Cut angle θ (/i) ih 3 Figure 5

Claims (1)

[Claims] In the contour-slip crystal resonator, the crystal resonator consists of a vibrating part and a support part, and excitation electrodes are arranged on the upper and lower surfaces of the vibrating part, and one support part has an excitation electrode on one side only, and a support part on the other side. An electrode connected to the excitation electrode is arranged only on the opposite surface of the support part to the one support part, and the vibrator is formed of a plate rotated by 46° to 53° with the Y plate as the rotation axis, and A contour slip crystal oscillator characterized in that the oscillator is formed by chemical etching.