In these resonators the heating tempera¬ture of the piezoelement is extremely non-uniform. Ensuring uniform heating of the piezoelement by means of a heater made in the form of a thin film and directly deposited on the piezoelement is made difficult by the fact that there is no free space on the surface of the piezoelement where the heater can be placed since the surface of the piezoelement is occupied by the electrodes deposited on it.nIn the proposed piezoelectric resonator with a heating element, piezoelectric resonator electrodes made in the form of a ribbon spiral divided by insulating grooves are used as a heating element for uniform heating of the whole surface of the resonator. The heat liberated as the electric current flows through the film covering will uniformly heat the whole surface of the piezoelement to the required temperature in a short time if the value of the current is selected in a suit-able manner. In order to heat the piezoelement more uniformly, the conducting covering may have dividing lines located in a manner such that the current density will be as alike as possible over the whole surface of the covering.
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