SU915223A1 - Method of frequency tuning of vacuum piezoelectric resonators - Google Patents

Description

The invention relates to electronics and can be used in the manufacture of piezoelectric resonators.

A known method of adjusting the frequency of piezoelectric resonators, based on a change in the mass of the active zones of the piezoelectric element, in which a part of the mass of the piezoelectric element is mechanically removed before it is evacuated Γΐ].

The disadvantages of this method are the low frequency tuning accuracy and the deterioration of the good quality of the resonators after tuning.

Also known is a method of adjusting the frequency of vacuum piezoelectric resonators, in which excitation electrodes are applied to a piezoelectric element in a vacuum chamber, evacuate the resonator and adjust the frequency by plasma action by applying a high voltage between the additionally inserted electrode and the plasma concentrator located on the exciting electrode of the piezoelectric element [2].

The disadvantage of this method is the low tuning accuracy, which is associated with a significant area of plasma effect on piezo 2

element and frequency change after evacuation of the resonator.

The purpose of the invention is to improve the accuracy of setting the frequency of vacuum

piezoelectric resonators.

This goal is achieved by the fact that according to the method of adjusting the frequency of vacuum piezoelectric resonators, in which the exciting electrodes are applied to the piezoelectric cell in the vacuum chamber, the resonator is evacuated and the frequency is adjusted by the action of plasma by applying high electrical voltage

15 between the additionally inserted electrode and the plasma concentrator located on the exciting electrode of the piezoelectric element, after applying the exciting electrodes, they are protected outside the location of the plasma concentrator with the process screen, and the frequency is adjusted before evacuating the resonator in the same vacuum chamber.

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Figure 1 shows a piezoelectric resonator subject to adjustment by the proposed method; in Fig.2 block diagram of the installation to configure

30 and vacuum resonator.

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915223

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The piezoelectric resonator contains a piezoelectric element 1 with exciting electrodes 2 and 3, on which plasma concentrators 4 and 5 are located. from electrically conductive material. The piezoelectric element 1 is mounted on the base 5. 5 Before setting up, the piezoelectric element 1 is protected with a technological screen 7 outside the location of the concentrators 4 and 5.

A piezoelectric resonator with a '10 technological screen 7 is placed in a vacuum chamber 8, in which a pressure of 1-5 · 10' ³ mm Hg is created. An inert gas, for example argon, is then injected into the chamber 8. The pressure is maintained at a pressure of 5 · "* ^l -1 -10 ' ¹ } mm Hg. Using a switch 9, a frequency meter 10 is connected to the resonator. After that, using a switch 9, a high voltage source 11 is connected to the resonator 20. This mode ensures the ignition mode and maintains an anomalous glow discharge, while using switch 12, this voltage is applied to one of the concentrators 4 or 5 by 25. frequency high voltage is first fed to one of the hubs, and then zd drugoy.- as hubs 4 and 5 can be used solder particles soldered to the excitation electrodes 2 and 3.

A glow discharge in the vacuum chamber 8 is maintained between concentration-. 4 or 5 and an additional electrode 13. The removal of the material, concentrators, and, consequently, the speed of adjustment, linearly depend on the time of exposure to a glow discharge. Therefore, the required tuning mode is easily set by nomograms. Setup is carried out

at voltages 0.8-2.5 kV. At a current through the discharge gap of 7–10 µA, a frequency tuning value of 20 · .10 * 5 of the nominal frequency is provided. At the same time, the tuning accuracy is ± 5 · 10 * ⁶ .

The proposed method provides high frequency tuning accuracy, does not impair the electrical parameters of the resonators and ensures high adaptability of the tuning operation.

Claims (1)

Claim The method of adjusting the frequency of the vacuum piezoelectric resonators, in which the exciting electrodes are applied to the piezoelectric element in the vacuum chamber, evacuates the resonator and adjusts the frequency by the action of plasma by applying a high voltage between the additionally introduced electrode and the plasma concentrator located on the exciting electrode of the piezoelectric element, which is , in order to increase the tuning accuracy, after applying the exciting electrodes they are protected outside the location of the plasma concentrator s screen process, and the frequency setting is carried out before evacuation of the resonator in the same vacuum chamber.