DEVICE FOR CHECKING AIR PRESSURE IN VEHICLE WHEEL TYRES Russian patent published in 1995 - IPC

FIELD: transport facilities. SUBSTANCE: device for checking air pressure in wheel tyres has two induction converters 1 and 2 in form of permanent magnets 3 and 4 intended for mounting on corresponding wheels and induction coils 5 and 6 made for mounting on vehicle fixed parts for interaction with corresponding magnets; device has also signal processing and display unit 8 with two information light-emitting diodes 9 and 10, blocking diode 11, indicating light-emitting diode 12 and shunting resistor 13. Change in tyre air pressure causes change in their radius and rotational frequency. Information signals of wheels induce in induction coils 5 and 6 pass along coupling channel 7 to high-emitting diodes 9 and 10 and the latter register wheel rotational frequency. Indicating light-emitting diode 12 separates frequency difference. Blocking diode 11 protects indicating light- emitting diode 12 from double reverse voltage, and shunting resistor 13 is selected to provide lighting of light-emitting diode 12 only when pulses on light-emitting diodes 9 and 10 coincide. Air pressure difference in corresponding pair of vehicle wheels can be judged by operation frequency of light-emitting diode 12. EFFECT: enlarged operating capabilities, enhanced reliability. 6 dwg