Arrangement of monitoring the operating state of vehicle pneumatic tires mounted on wheel rims

• US 5,235,850 A
• Filed: 01/08/1992
• Issued: 08/17/1993
• Est. Priority Date: 01/09/1991
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments Deutschland Gesellschaft Mit Beschrã¤Nkter Haftung (Texas Instruments, Inc.)
• Inventors: Schurmann, Josef
• Primary Examiner(s): WOODIEL, DONALD
• Application Number:
  US07/818,190
• Time in Patent Office: 587 Days
• Field of Search: 73/146.5, 73/146.8, 73/146.2, 374/143, 340/443, 340/445, 340/448, 340/447
• US Class Current: 73/146.5
• CPC Class Codes: B60C 23/0461 externally triggered, e.g. by wireless request signal, magnet or manual switch
• CPC Class Codes: B60C 23/0493 for attachment on the tyre
• CPC Class Codes: B60C 23/0498 for rim attachments B60C23/0494, B60C23/0496 take precedence
• CPC Class Codes: G06K 19/07764 the adhering arrangement making the record carrier attachable to a tire tire temperature or pressur control arrangements, see B60C23/00
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer

Abstract

An arrangement for monitoring the operating state of vehicle pneumatic tires (14) mounted on wheel rims (10) is provided with sensors (40, 42) for detecting the air pressure and the air temperature in each tire. Furthermore, it includes transmitting means comprising rim-side mounted rotor members (28) and bodywork-side mounted stator members (32) coupled thereto for transmitting the parameters detected by the sensor (40, 42) to an evaluating arrangement in the vehicle connected to the stator members. The pressure sensor (40) and the temperature sensor (42) of each tire (14) are coupled to a first transponder (44) which as reaction to an interrogation signal generated by the evaluating arrangement transmits the data supplied to it by the pressure sensor (40) and the temperature sensor (42) to the rotor members (28) of the transmitting means. Disposed in the pneumatic tire (14) is a second transponder (48) which when it receives the interrogation signal transmits data designating the type of the pneumatic tire (14) to the stator members (32 ).

Claims

1. System for monitoring the operating state of vehicle pneumatic tires, which are comprised of tire material and have tire beards and side walls, mounted on wheel rims comprising:

sensors for detecting the air pressure and the air temperature in each tire;

transmitting means comprising rim-side mounted rotor members and bodywork-side mounted stator members coupled thereto for transmitting the parameters detected by the sensors to an evaluating arrangement in a vehicle connected to the stator members;

a first transponder, coupled to said temperature sensor and said pressure sensor, which in response to an interrogation signal generated by the evaluating arrangement, transmits temperature and pressure data supplied to said transponder by the pressure sensor and the temperature sensor to the rotor members of the transmitting means;

a second transponder, which is disposed in the pneumatic tires, and which, in response to an interrogation signal generated by the evaluating arrangement, transmits data to the stator members designating the type of the pneumatic tire.

2. System according to claim 1, wherein the transmitting power of the second transponder is higher than the transmitting power of the first transponder.

3. System according to claim 2, wherein the difference between the transmitting powers of the first and second transponders is greater than 1.5 Db.

4. System according to claim 2, wherein the difference between the transmitting powers of the first and second transponders falls within the range from 3 to 6 Db.

5. System according to claim 1, wherein the stator members are located with respect to the first and second transponders such that the second transponder is operable to generate a maximum field strength at the stator members that is greater than the field strength which can be generated by the first transponder.

6. System according to claim 1, wherein the second transponder is embedded into the tire material in the region of the tire bead.

7. System according to claim 1, wherein the second transponder is mounted on a side wall of the pneumatic tire.

8. System according to claim 1, wherein the first and second transponders are batteryless transponders which obtain their supply energy from the interrogation signal received by them.