Patent ID: 7131323

Claim:
A tire inflation pressure sensing apparatus comprising: a first pressure sensor provided on a running wheel of a vehicle, said first pressure sensor working to sense an inflation pressure of a tire mounted on the running wheel and generate a pressure signal representative of the sensed inflation pressure; a first transmitter provided on the running wheel of the vehicle, said first transmitter being configured to send out the pressure signal generated by said first pressure sensor upon being triggered by a trigger signal; a second pressure sensor provided on a spare wheel of the vehicle, said second pressure sensor working to sense an inflation pressure of a tire mounted on the spare wheel and generate a pressure signal representative of the sensed inflation pressure; a second transmitter provided on the spare wheel of the vehicle, said second transmitter being configured to send out the pressure signal generated by said second pressure sensor upon being triggered by the trigger signal; and a receiver provided on a body of the vehicle, said receiver being configured to: send out the trigger signal; operate in a first mode if only the pressure signal sent out from said first transmitter is received, in the first mode said receiver determining the inflation pressure of the tire on the running wheel of the vehicle based on the received pressure signal; and operate in a second mode if both the pressure signals sent out from said first and said second transmitters are received, in the second mode said receiver generating one RSSI (Received Signal Strength Indicator) signal for each of the two pressure signals, identifying whether each of the two pressure signals is sent out from said first transmitter or said second transmitter based on the RSSI signal generated therefor, and determining the inflation pressure of the tire on the running wheel of the vehicle based on the pressure signal sent out from said first transmitter.