Method and apparatus using directional antenna or learning modes for tire inflation pressure monitoring and location determination

• US 20020092345A1
• Filed: 01/17/2001
• Published: 07/18/2002
• Est. Priority Date: 01/17/2001
• Status: Active Grant

• Current Assignee: Microchip Technology Incorporated
• Original Assignee: Microchip Technology Incorporated
• Inventors: Van Niekerk, Jan, Katz, Paul N., Uradnik, Joseph A., St. Amand, Roger
• Granted Patent: US 6,571,617 B2
• Time in Patent Office: Days
• US Class Current: 73/146
• CPC Class Codes: B60C 23/008 having wheels on more than two axles
• CPC Class Codes: B60C 23/0479 Communicating with external units being not part of the vehicle, e.g. tools for diagnostic, mobile phones, electronic keys or service stations
• CPC Class Codes: G01L 17/00 Devices or apparatus for measuring tyre pressure or the pressure in other inflated bodies
• CPC Class Codes: G01M 17/02 Tyres

Abstract

A wireless tire inflation pressure measurement device is used to obtain inflation pressure information for a tire of a vehicle and a signal therefrom may be used for determining the location of the tire. An identifier may be associated with the inflation pressure information for each wheel of the vehicle. Tire rotation speed may be determined by amplitude fluctuations of a radio frequency carrier from a radio frequency transmitter rotating with the wheel. Differences in wheel rotation speeds during a turn may be used in determining the location of each tire of the vehicle. An antenna may be placed on each wheel toward the outer perimeter of the wheel and connected to the radio frequency transmitter. A radio frequency identification (RFID) tag and pressure sensor may be used as the wireless tire inflation pressure measurement device and a RFID pickup coil may be provided in each wheel well for pickup of the inflation pressure signals from each RFID tag on a wheel.

Claims

4EM1. EM1. A method for determining inflation pressures of tires and locations thereof on wheels of a vehicle, said method comprising the steps of:

providing a wireless inflation pressure measuring device for each wheel of a vehicle, each of the wireless inflation pressure measuring devices transmits a radio frequency signal containing inflation pressure information; and

providing a inflation pressure monitor having a radio frequency receiver adapted for receiving the radio frequency signals from each of the inflation pressure measuring devices with a directional signal location antenna device, wherein a transmission point for each of the radio frequency signals may be determined and thereby define the locations of the wheels on the vehicle.

4EM2. EM2. The method of claim 4EM1, wherein the inflation pressure monitor alarms upon detecting a low inflation pressure and indicates the location of the wheel having the low inflation pressure.

4EM3. EM3. The method of claim 4EM1, further comprising the step of encrypting the inflation pressure information.

4EM4. EM4. The method of claim 4EM1, further comprising the steps of:

providing a temperature sensor coupled to the wireless inflation pressure measuring device; and

measuring tire temperature with the temperature sensor, wherein the radio frequency signal further comprises tire temperature information.

4EM5. EM5. The method of claim 4EM4, further comprising the step of calculating a corrected tire pressure for each tire of the vehicle based upon the respective tire temperature and pressure.

4EM6. EM6. The method of claim 4EM1, further comprising the step of generating an alert signal when a tire pressure is at a desired pressure.

4EM7. EM7. The method of claim 4EM1, further comprising the step of generating an alert signal when a tire pressure exceeds a maximum pressure.

4EA1. EA1. An apparatus for determining inflation pressures of tires and locations thereof on wheels of a vehicle, comprising:

a wireless inflation pressure measuring device for each wheel of a vehicle, wherein each of the wireless inflation pressure measuring devices transmits a radio frequency signal comprising inflation pressure information of a tire mounted on a respective one of the wheels; and

an inflation pressure monitor having a radio frequency receiver adapted for receiving the radio frequency signals from each of the inflation pressure measuring devices with a directional signal location antenna device, wherein a transmission point for each of the radio frequency signals may be determined and thereby define the locations of the wheels on the vehicle.

4EA2. EA2. The apparatus of claim 4EA1, wherein the inflation pressure monitor alarms upon detecting a low inflation pressure and indicates the location of the wheel having the low inflation pressure.

4EA3. EA3. The apparatus of claim 4EA1, further comprising an encryption circuit for encrypting the tire inflation pressure information.

4EA4. EA4. The apparatus of claim 4EA1, further comprising an alert signal when a tire pressure is at a desired pressure.

4EA5. EA5. The apparatus of claim 4EA1, further comprising an alert signal when a tire pressure exceeds a maximum pressure.

7EM1. EM1. A method for measuring inflation pressures of tires on wheels of a vehicle, said method comprising the steps of:

providing a wireless inflation pressure measuring device for each wheel of a vehicle, wherein the wireless inflation pressure measuring devices provide inflation pressure information and a identifier for each of the vehicle wheels; and

providing a inflation pressure monitor that is adapted to read the tire inflation pressure information and the identifier from each of the wireless inflation pressure measuring devices, wherein the inflation pressure monitor has a learning mode whereby wheel locations are correlated with the identifiers for subsequent indication of tire inflation pressure of each wheel and the location thereof.

7EM2. EM2. The method of 7EM1, wherein the wireless inflation pressure measuring device is a pressure sensor, radio frequency transmitter and antenna.

7EM3. EM3. The method of 7EM1, wherein the wireless inflation pressure measuring device is a pressure sensor and radio frequency identification (RFID) tag and the inflation pressure monitor includes a RFID tag reader.

7EM4. EM4. The method of claim 7EM1, further comprising the step of encrypting the inflation pressure information.

7EM5. EM5. The method of claim 7EM1, further comprising the step of generating an alert signal when a tire pressure is at a desired pressure.

7EM6. EM6. The method of claim 7EM1, further comprising the step of generating an alert signal when a tire pressure exceeds a maximum pressure.

7EA1. EA1. An apparatus for measuring inflation pressures of tires on wheels of a vehicle, comprising:

a wireless inflation pressure measuring device for each wheel of a vehicle, wherein the wireless inflation pressure measuring devices provide tire inflation pressure information and a identifier for each tire on the vehicle wheels; and

a tire inflation pressure monitor that is adapted to read the tire inflation pressure information and the identifier from each of the wireless inflation pressure measuring devices, wherein the inflation pressure monitor has a learning mode in which to correlate wheel locations with the identifiers for later indication of inflation pressure of the tire and its corresponding location on a wheel of the vehicle.

7EA2. EA2. The apparatus of 7EA1, wherein the wireless tire inflation pressure measuring device is a pressure sensor, radio frequency transmitter and antenna.

7EA3. EA3. The apparatus of 7EA1, wherein the wireless tire inflation pressure measuring device is a pressure sensor and radio frequency identification (RFID) tag and the inflation pressure monitor includes a RFID tag reader.

7EA4. EA4. The apparatus of claim 7EA1, further comprising an encryption circuit for encrypting the tire inflation pressure information and identifier.

7EA5. EA5. The apparatus of claim 7EA1, further comprising an alert signal when a tire pressure is at a desired pressure.

7EA6. EA6. The apparatus of claim 7EA1, further comprising an alert signal when a tire pressure exceeds a maximum pressure.

8EM1. EM1. A method for measuring inflation pressures of tires on wheels of a vehicle, said method comprising the steps of:

providing a wireless inflation pressure measuring device for each wheel of a vehicle, wherein the wireless inflation pressure measuring devices provide tire inflation pressure information and a identifier for each of the vehicle tires; and

providing a inflation pressure monitor that is adapted to read the inflation pressure information and the identifier from each of the wireless inflation pressure measuring devices, wherein each of the identifiers is marked on the respective wheels so as to correlate wheel locations with the identifiers for later indication of inflation pressure of each tire and location thereof.

8EM2. EM2. The method of 8EM1, wherein the wireless inflation pressure measuring device is a pressure sensor, radio frequency transmitter and antenna.

8EM3. EM3. The method of 8EM1, wherein the wireless inflation pressure measuring device is a pressure sensor and radio frequency identification (RFID) tag and the inflation pressure monitor is coupled to a RFID tag reader.

8EM4. EM4. The method of claim 8EM1, further comprising the step of encrypting the inflation pressure information and the identifier.

8EM5. EM5. The method of claim 8EM1, further comprising the step of generating an alert signal when a tire pressure is at a desired pressure.

8EM6. EM6. The method of claim 8EM1, further comprising the step of generating an alert signal when a tire pressure exceeds a maximum pressure.

8EA1. EA1. An apparatus for measuring inflation pressures of tires on wheels of a vehicle, comprising:

a wireless inflation pressure measuring device for each tire of a vehicle, wherein the wireless inflation pressure measuring devices provide tire inflation pressure information and a identifier for each tire on the wheels of the vehicle; and

an inflation pressure monitor that is adapted to read the tire inflation pressure information and the identifier from each of the wireless tire inflation pressure measuring devices, wherein each of the identifiers is marked on the respective wheels so as to correlate wheel locations with the identifiers for later indication of inflation pressure and location of each tire.

8EA2. EA2. The apparatus of 8EA1, wherein the wireless tire inflation pressure measuring device is a pressure sensor, radio frequency transmitter and antenna.

8EA3. EA3. The apparatus of 8EA1, wherein the wireless tire inflation pressure measuring device is a pressure sensor and radio frequency identification (RFID) tag and the inflation pressure monitor is coupled to a RFID tag reader.

8EA4. EA4. The apparatus of claim 8EA1, further comprising an encryption circuit for encrypting the tire inflation pressure information and identifier.

8EA5. EA5. The apparatus of claim 8EA1, further comprising an alert signal when a tire pressure is at a desired pressure.

8EA6. EA6. The apparatus of claim 8EA1, further comprising an alert signal when a tire pressure exceeds a maximum pressure.