Patent ID: 7425892

Claim:
A tire inflation pressure sensing apparatus comprising: a plurality of pressure sensors each of which is provided on one of a plurality of wheels of a vehicle, each of said pressure sensors working to sense an inflation pressure of a tire mounted on a corresponding one of the wheels and output a pressure signal representative of the sensed inflation pressure of the tire; a plurality of transmitters each of which is provided on one of the plurality of wheels of the vehicle, each of said transmitters being configured to receive the pressure signal outputted from a corresponding one of said pressure sensors and send out a pressure transmitting signal corresponding to the received pressure signal; a first receiver provided on a body of the vehicle, said first receiver being configured to receive the pressure transmitting signals sent out from said transmitters and determine the inflation pressures of the tires based on the respective received pressure transmitting signals; a plurality of second receivers each of which is provided on one of the plurality of wheels of the vehicle, each of said second receivers working to receive a signal generated by a signal source that is located in the vehicle and provide the received signal to a corresponding one of said transmitters; and a plurality of acceleration sensors each of which is provided on one of the plurality of wheels of the vehicle, each of said acceleration sensors working to generate an acceleration signal as a function of a circumferential acceleration of a corresponding one of the wheels and output the acceleration signal to a corresponding one of said transmitters, wherein each of said transmitters works to make a first determination for a corresponding one of the wheels of the vehicle as to whether the wheel is a front-wheel or a rear-wheel of the vehicle based on a level of the signal provided by a corresponding one of said second receivers and make a second determination for the same as to whether the wheel is a right-wheel or a left-wheel of the vehicle based on the acceleration signal outputted from a corresponding one of said acceleration sensors.