Gas Absorbers for Vibrational Gyroscopes

The effect of residual gas on oscillation damping of vibrational gyroscope resonators as well as properties ofdifferent getters and issues oftheir application for maintaining high vacuum in these devices are considered. In vibrational gyroscopes, a high rarefication must be maintained inside the device body, in particular, in micromechanical gyroscopes where the mass and overall dimensions characteristics are small and gaps amount to several micrometers. With consideration for the small volume of device body and the developed inner surface of micromechanical gyroscopes, the getter application seems to be necessary. It is recommended to apply non-evaporable getters, in which mixtures of zirconium, titanium, rare-earth metals and alloys based on them are used. Non-evaporable getters have high specific sorption capacity and can be regenerated after saturation by means of heating. While constructing gyroscopes, it is expedient to isolate getter from the vacuum volume of device till the completion of pumping and degasing as well as to avoid using materials that can emit hydrocarbons (adhesives, insulators, etc.).

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