Abstract: A tire parameter monitoring system has a plurality of sensor units for monitoring tire parameters, with each sensor unit mounted with a different vehicle tire. Each sensor unit has an RFID tag reader for interrogating an RFID tag securely mounted to the vehicle adjacent the corresponding tire and containing a unique identification code. Each sensor unit has a microcontroller for combining each RFID identification code with corresponding tire parameter signals, and a transmitter for transmitting the combined signals to a receiving location. Received tire parameter signals are correlated with the tire location using the RFID identification code, and driver advisory signals are presented to the driver by a display/alarm unit. Two alternative power supplies are provided. A first type uses a battery and a power management circuit for eliminating power drain when the RFID tag reader is energized. A second type uses inductive power to provide an inexhaustible power source.

Abstract: A tire parameter sensor unit for monitoring one or more vehicle tire parameters such as internal tire pressure and temperature and developing a permanent log of the operational history of the tire. The sensor unit has a power system, a processor/transmitter, a radio time clock, one or more sensors, and a memory mounted on a substrate. This assembly is permanently attached to the tire in the side wall or tread wall. Initial tire identification information is stored in the memory upon tire fabrication. During the lifetime of the tire, operational information specifying the tire operating conditions (pressure, temperature, etc.) is permanently stored in the memory along with real time data. The operational information and real time data can be read out from memory to provide the history log.

Abstract: A tire parameter monitoring system has a plurality of sensor units each mounted with a different vehicle tire. Each sensor unit has a magnetic sensing element for converting magnetic field signals generated by a proximate set of magnets mounted to the vehicle at the tire locations. Each magnet set generates a unique magnetic field which identifies the magnet set location. Each sensor unit has a microcontroller for combining the converted magnetic field signals with fire parameter signals, and a transmitter for transmitting the combined signals to a receiving location. Received tire parameter signals are correlated with the tire location using the location signals, and driver advisory signals are presented to the driver.

Abstract: A battery powered vehicle tire pressure sensor system has a power saving unit which controls the application of electrical power to the system as a function of tire speed to prolong battery life. The power saving unit has a power control switch which is responsive to tire angular speed. Each sensor assembly of the system is mounted on or in the side wall of a pneumatic tire to generate signals representative of tire pressure whenever power is applied. A processor periodically samples the signals. When the processor determines that the tire pressure is outside a safe range, an r.f. generator is activated by the processor to generate an unsafe tire pressure signal. This signal is converted by a receiver to a warning for the driver.

Abstract: A battery-less tire parameter sensor system for monitoring a vehicle tire parameter such as pressure and temperature. A sensor assembly has a power system, a processor/transmitter, a sensor, and a power coil mounted on a substrate. This assembly is mounted on or in the side wall or tread wall of a tire. A magnet is mounted on the vehicle in proximity to the path of the power coil during tire rotation. The moving power coil passes through the magnetic field and generates operating voltage for the sensor assembly components. The power system includes a voltage multiplier, a voltage regulator, and a storage capacitor. Two or more sensor assemblies can be mounted on the same tire to monitor different parameters.

Abstract: A battery powered tire pressure sensor system with a high sensitivity stretch sensor assembly having a variable resistance longitudinal displacement characteristic. The stretch sensor assembly has at least two juxtaposed stretch sensors, each with a first layer bearing the variable resistance element and a second support layer. The sensor assembly is mounted on or in the side wall of a pneumatic tire so that the assembly is displaced by the tire side wall and the resistance is a function of internal tire pressure. The assembly is coupled to a processor which samples the resistance of the stretch sensor assembly periodically. When the processor determines that the pressure is outside a safe range, an r.f. generator is activated by the processor to generate an unsafe tire pressure signal. This signal is converted by a receiver to a warning for the driver. A power saving unit controls application of electrical power to the system as a function of tire speed to prolong battery life.

Abstract: An external mount tire pressure sensor system with a stretch sensor having a variable resistance longitudinal displacement characteristic. The stretch sensor is coupled to a processor which samples the resistance of the stretch sensor periodically. The sensor body is attached to the external side wall of a pneumatic tire so that the body is displaced by the tire side wall and the resistance is a function of internal tire pressure. When the processor determines that the pressure is below a threshold value, an r.f. generator is activated by the processor to generate a low tire pressure signal. This signal is converted by a receiver to a warning for the driver.