A device for indicating, on the vehicle's control panel inside the driver's cabinet during driving or stopping, the minimum and the maximum pneumatic pressure limits (lower and upper safety thresholds) in the inflated tyres of the vehicle.

摘要

A device for indicating, on the vehicle's driving panel duri­ng driving or stopping, the minimum and the maximum pressure limits (lower and upper thresholds) which is inside the infla­ted tyres of the vehicle. The device, which can transmit the dangerous limits of the pressure in the inflated tyres into the driving panel, can operate with the help of two isolated metallic strips (2, 3 or 151, 152) which play the role of a plate or cylindrical capacitor respectivelly, of one electro­nic circuit (27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 12, 11, 10, 9, 8, 5, 7, 3, 2, 32, 1, 28, 4, 6, 34, 29, 30) and of one pressure gauge (transducer) (1) which is a kind of an electric switch of the above circuit. One of the metallic strips (2 or 151) is placed on the rotating wheel and the other strip (3 or 152) is fixed on the non-rotating frame of the vehicle's chassis near to the wheel and very close to the first metallic strip so that to be a plate or cylindrical air capacitor. The electronic circuit produces alternative volta­ge in the ends of the coil (10) and when the pressure gauge close a circuit, by grounding the plate (2) on the metallic frame of the wheel (rim), in case of dangerous pressures, an alternating current flows in the circuit, which activates the photodiode (5).