FIELD: automotive industry; controls and instruments. SUBSTANCE: device is designed for putting out warning signals if pressure in automobile tyre drops below tolerable value. Oscillatory circuit is installed on vehicle wheel. This circuit is shunted by change-over switch in case of inadmissible pressure drop and is inductively coupled with coupling coil installed on vehicle body. Coupling coil is connected with generator through current amplifier and, through comparator, with one of inputs of logic phase detector whose other input is connected to generator output. Detector reveals change in phase of signal on coil at shunting of oscillatory circuit and switches on pressure drop indicator. EFFECT: enhanced operation reliability owing to use of phase principle of detection. 3 dwg
