PROCESS OF FORMATION OF ULTRASONIC FIELD TO SCARE AWAY RODENTS AND GEAR FOR ITS IMPLEMENTATION Russian patent published in 1998 - IPC

FIELD: protection of objects from actions of rodents by means of ultrasonic signal. SUBSTANCE: during formation of ultrasonic field signal changes in each period from 20 to 70 kHz. Period of each pulse lasts 20-40 ms and rate of change of signal frequency is comparable with constant of conversion time of electric signal by piezoelectric radiator into ultrasonic field. Gear for implementation of process includes frequency modulator, retunable generator of electric signal, power amplifier of electric signal and piezoelectric radiator connected in series. With parameters of electric signal specified above and rate of change of its frequency efficiency of scaring away rodents is the highest. EFFECT: maximum efficiency of scaring away rodents. 2 cl, 2 dwg , 1 tbl