System and method for determining at least one parameter of at least one rotating member by means of reference and speed signals

• US 7,271,733 B2
• Filed: 11/16/2004
• Issued: 09/18/2007
• Est. Priority Date: 11/21/2003
• Status: Expired due to Fees

• Current Assignee: SNR Roulements
• Original Assignee: SNR Roulements
• Inventors: Duret, Christophe, Nicot, Christophe
• Primary Examiner(s): Hofsass; Jeffery
• Assistant Examiner(s): AU, SCOTT D
• Application Number:
  US10/988,570
• Publication Number:
  US 20050110626A1
• Time in Patent Office: 1,036 Days
• Field of Search: 340/825.49, 340/10.1, 340/445, 731/46
• US Class Current: 340/524
• CPC Class Codes: B60C 23/0408 transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
• CPC Class Codes: B60C 23/0433 Radio signals

Abstract

The invention concerns a system for determining at least one parameter of at least one member (1) rotating with respect to a fixed structure (2), comprising, for each rotating member (1), an assembly comprising a transponder (3), a code (5) comprising a reference singularity, a sensor (6) able to deliver a signal comprising a reference pulse corresponding to the detection of the reference singularity, a device (4) for detecting the parameter or parameters issuing from the transponder (3) and a device for measuring the speed of rotation of the rotating member (1);

the said system also comprising an activation device (7) which is connected to each sensor (6), to each detection device (4) and to each speed measurement device, the said activation device being able, when a reference pulse issuing from the sensor (6) of an assembly is recorded, to activate the detection device (4) of the assembly at a moment which is a function of the indexed position of the transponder (3) and of the measured speed, so that the transponder (3) of the assembly is in the transmission/reception cone of the communication means of the said detection device.

Claims

1. A system for determining at least one parameter of at least one member (1) rotating with respect to a fixed structure (2), said system comprising, for each rotating member (1), an assembly comprising:

a transponder (3) rotationally fixed to the rotating member (1), the transponder being able to measure the parameter or parameters to be determined;

a coder (5) rotationally fixed to the rotating member (1), the coder comprising a reference singularity whose angular position is indexed with respect to the angular position of the transponder (3) on the rotating member (1);

a sensor (6) fixed to the fixed structure (2), the sensor being disposed opposite to and at a reading distance from the coder (5), the sensor being able to deliver a rotation pulse signal comprising a reference pulse corresponding to the detection of the reference singularity;

a detection device (4) for detecting the parameter or parameters issuing from the transponder (3), the device being fixed to the fixed structure (2) and comprising a communication means able to send an excitation signal to the transponder (3) and to receive the measurement or measurements, said communication means having a transmission/reception cone;

a device for measuring the speed of rotation of the rotating member (1);

said system also comprising;

an activation device (7) which is connected to each sensor (6), to each detection device (4) and to each speed measurement device, the activation device being able, when a reference pulse issuing from the sensor (6) of an assembly is recorded, to activate the assembly detection device (4) at a moment which is a function of the indexed position of the transponder (3) and of the measured speed, so that the transponder (3) of the assembly is in the transmission/reception cone of the communication means of the detection device.

2. A system according claim 1, characterised in that the coder (5) comprises a main multipole track and a rotation pulse multipole track which are concentric, the rotation pulse track comprising the reference singularity, the sensor (6) comprising an electronic circuit delivering the rotation pulse signal and forming a device for measuring the speed of rotation.

3. A system according to claim 2, characterised in that the coder (5) is formed from a magnetic ring comprising on its surface the main track and the rotation pulse track which are concentric, the tracks comprising a succession of North and South poles, the reference singularity being produced by a magnetic transition which is different from the others.

4. A system according to any one of claims 1 to 3, characterised in that the reference singularity is indexed with respect to all the possible angular positions of the transponder (3) on the rotating member (1), the activation device (7) being able, when the reference pulse is recorded, to activate the detection device (4) when each possible angular position of the transponder is in the transmission/reception cone of the communication means.

5. A system according to any one of claims 1 to 3, characterised in that each coder (5) also comprises pulse coding means which are different from one coder (5) to another, the activation device (7) comprising means for identifying the coding so as to activate the detection device (4) corresponding to the assembly of the coder (5) from which the pulse came.

6. A system according to claim 5, characterised in that the coding means comprise a number of supplementary singularities which are distributed on the coder.

7. A method of determining at least one parameter of at least one member (1) rotating with respect to a fixed structure (2) by a system according to claim 1, in which, when a reference pulse is recorded, the activation device (7) determines an activation time as a function of the measured speed and the indexed position of the transponder (3), the device activating the detection device (4) after the elapse of this time.

8. A method according to claim 7, characterised in that it comprises a procedure of recalculating the time according to the variations in speed occurring before the activation.

9. A method according to claim 8, characterised in that the indexed position of the transponder (3) with respect to the reference singularity is previously stored in the activation device (7).

10. A method according to claim 8, characterised in that it comprises a prior procedure of indexing the position of the reference singularity with respect to the angular position of the transponder (3) on the rotating member (1).

11. A method according to claim 10, characterised in that the indexing procedure is effected by activating the detection device (4) at fixed frequency and, when the signal measured by the device is satisfactory, determination of the position indexed when the following reference pulse is detected.

12. A method according to claim 7, characterised in that the indexed position of the transponder (3) with respect to the reference singularity is previously stored in the activation device (7).

13. A method according to claim 7, characterised in that it comprises a prior procedure of indexing the position of the reference singularity with respect to the angular position of the transponder (3) on the rotating member (1).

14. A method according to claim 13, characterised in that the indexing procedure is effected by activating the detection device (4) at fixed frequency and, when the signal measured by the device is satisfactory, determination of the position indexed when the following reference pulse is detected.

15. A method according to any one of claims, 7, 8, 12, 13, 14, 9, 10, or 11, characterized in that it comprise an iterative procedure of optimising the indexed position in which the quality of the signal issuing from the detection device (4) is analyzed, and, if the quality is below a threshold, the indexed position is incremented and/or decremented by a given step in order to determine a new optimised indexed position which is used subsequently by the activation device (7).

16. A method according to claim 13, characterised in that it comprises an iterative procedure of optimising the indexed position in which the quality of the signal issuing from the detection device (4) is analysed, and, if the quality is below a threshold, the indexed position is incremented and/or decremented by a given step in order to determine a new optimised indexed position which is used subsequently by the activation device (7) in which, if the quality of the signal is below a second threshold which is below the first threshold, the indexing procedure is carried out in place of the optimisation procedure.

17. A method according to claim 7, characterised in that the activation time is also a function of the operating conditions of the rotating member (1).

18. A motor vehicle comprising a system according to any one of claims 1 to 3, each assembly being disposed so as to determine at least one parameter of a tyre (1) of the said vehicle.

19. A vehicle according to claim 18, characterised in that the communication means is housed in the arch of the wheel on which the tyre (1) is mounted and in that the transponder (3) is housed in the valve of the tyre (1).

20. A motor vehicle comprising a system to claim 4, each assembly being disposed so as to determine at least one parameter of a tyre (1) of the said vehicle.

21. A vehicle according to claim 20, characterised in that the communication means is housed in the arch of the wheel on which the tyre (1) is mounted and in that the transponder (3) is housed in the valve of the tyre (1).

22. A motor vehicle comprising a system to claim 5, each assembly being disposed so as to determine at least one parameter of a tyre (1) of the said vehicle.

23. A vehicle according to claim 22, characterised in that the communication means is housed in the arch of the wheel on which the tyre (1) is mounted and in that the transponder (3) is housed in the valve of the tyre (1).

24. A motor vehicle comprising a system to claim 6, each assembly being disposed so as to determine at least one parameter of a tyre (1) of the said vehicle.

25. A vehicle according to claim 24, characterised in that the communication means is housed in the arch of the wheel on which the tyre (1) is mounted and in that the transponder (3) is housed in the valve of the tyre (1).