WHEEL-MONITORING MODULE

• US 20100256946A1
• Filed: 11/30/2007
• Published: 10/07/2010
• Est. Priority Date: 11/30/2007
• Status: Active Grant

• Current Assignee: Volvo Technology Corporation
• Original Assignee: Volvo Lastvagnar AB (Volvo AB)
• Inventors: Trygg, Anders, Hasselberg, Per, Carresjö, Erik
• Granted Patent: US 10,035,387 B2
• Time in Patent Office: Days
• US Class Current: 702/138
• CPC Class Codes: B60C 23/0462 Structure of transmission protocol
• CPC Class Codes: B60C 23/0474 Measurement control, e.g. setting measurement rate or calibrating of sensors; Further processing of measured values, e.g. filtering, compensating or slope monitoring
• CPC Class Codes: G01L 17/00 Devices or apparatus for measuring tyre pressure or the pressure in other inflated bodies
• CPC Class Codes: G01L 27/00 Testing or calibrating of apparatus for measuring fluid pressure
• CPC Class Codes: G07C 5/085 using electronic data carriers

Abstract

A module is operable to monitor at least a pressure within a tire of a wheel, the module being operatively mounted to said wheel, the module including:

• (a) a pressure sensor for measuring the pressure (P) and generating a corresponding pressure signal; and
• b1) an associated data memory including a data field containing data relevant to the functional status of the tyre.

Claims

1. A module operable to monitor at least a pressure within a tire of a wheel, the module being operatively mounted to the wheel, the module includes:

(a) a pressure sensor for measuring the pressure and generating a corresponding pressure signal; and

b1) an associated data memory including a data field containing data relevant to the functional status of the tyre;

wherein

the module includes a flag which can be set by a data processor to represent “

VALID”

or “

INVALID”

for denoting validity or invalidity of the data relevant to the functional status of the tire and that the flag is set to be changed from “

VALID”

to “

INVALID”

as soon as the pressure measured by the pressure sensor falls below the predetermined threshold value.

2. A module according to claim 1, wherein the data field containing data relevant to the functional status of the tire including one or more of the following data:

a) tire slip curves,

b) tire size,

c) tire age

d) a record of the distance the tire has been used,

e) a field containing record of samples of pressure measured by the pressure sensor,

f) a field containing record of samples of the temperature measured by a temperature sensor mounted on the wheel for monitoring the temperature of the tyre

3. A module according to claim 1, wherein the data processor is prevented to change the flag from “

INVALID”

to “

VALID”

unless a key code signal is received externally from the module.

4. A module according to claim 1, wherein the data processor is operable to change the flag from “

INVALID”

to “

VALID”

when a key code signal is received externally from the module.

5. A module according to claim 1, wherein the data processor is operable to monitor the pressure measured by the pressure sensor and to maintain the flag as “

VALID”

as long as the pressure is maintained above a predetermined threshold value, and to set the flag to “

INVALID”

invalid as soon as the pressure measured by the pressure sensor falls below the predetermined threshold value.

6. A module according to claim 1, wherein the field containing data relevant to the functional status of the tire includes a field containing record of samples of pressure measured by the pressure sensor, and that the data processor is operable to set the flag to “

INVALID”

when the record of samples contains at least one sample below the predetermined threshold value.

7. A module according to claim 1, wherein the data processor is coupled in communication with the associated data memory and operable to receive the pressure signal is arranged in the module.

8. A module according to claim 1, wherein the pressure sensor is mounted on a rim of the wheel.

9. A module according to claim 1, wherein the module further comprising

(c) a wireless interface coupled in communication with the processor for enabling the processor to communicate externally to the module;

(d) a source of power for providing operating power for the module;

Wherein the data processor is operable to a generate a record of the pressure as a function of time in the data memory for monitoring the wheel and its tire and to communicate information derived from the record via the wireless interface for enabling a condition of the wheel to be monitored externally to the module.

10. A module as claimed in claim 1, wherein the module is operable to detect depressurization events experienced by the wheel and an exchange of the tire include corresponding information in the record.

11. A module as claimed in claim 1 mountable at one or more locations on the wheel, the one or more locations including:

(a) on a hub of the wheel substantially at an axis of rotation of the wheel;

(b) on a hub of the wheel at a radial distance from the axis of rotation of the wheel;

(c) on a hub of the wheel in fluid communication with a filling valve (80) of a tire of the wheel for sensing a pressure within the tire;

(d) within a tire of the wheel for sensing a pressure within the tire, the module being mounted to a peripheral surface of a hub of the wheel;

(e) within a tire of the wheel for sensing a pressure within the tire, the module being mounted to an inside side-wall surface of said the tire for measuring flexural characteristics of the side-wall; and

(f) on an inside surface of a peripheral rim of the wheel for measuring acceleration thereat.

12. A module as claimed in claim 1, wherein the module includes a temperature sensor for sensing a temperature thereat, the temperature sensor being operable to generate a temperature signal representative of the temperature for receipt at the data processor for at least one of recording in the data memory and communicating via the wireless interface externally to the module.

13. A module as claimed in claim 1, wherein the module includes at least one of:

(a) a strain gauge sensor for measuring flexure of the tire of the wheel, the strain gauge sensor being operable to generate a signal indicative of the flexure for receipt at the data processor for at least one of recording in the data memory and communicating via the wireless interface externally to the module;

(b) an accelerometer for measuring acceleration in at least one axis at a mounting location of the module on the wheel, the accelerometer being operable to generate a signal indicative of the acceleration for receipt at the data processor for at least one of recording in the data memory and communicating via the wireless interface externally to the module; and

(c) a magnetic sensor for measuring a magnetic field applied to the module, the module being operable to generate a signal indicative of the applied magnetic field to the data processor for at least one of recording in the data memory and communicating via the wireless interface externally to the module.

14. A module as claimed in claim 1, wherein the module is provided with a corresponding identification code for communicating to a processing arrangement external to the module, so that a processing arrangement operatively in communication with the module is able to recognize the module when corresponding signal data has been sent therefrom and attribute the signal data to the module.

15. A module as claimed in any-preceding claim 1, wherein the data processor is coupled to the data memory, and the module via its pressure sensor is operable to record the pressure within the tire of the wheel in relation to time as determined by a clock arrangement included within the module, and the processor is operable to monitor changes in the pressure with time to identify one or more of:

(a) a gradual leak of air or gas from the tire indicative of a need to recharge the tire with air or gas; and

(b) any abrupt depressurization of the tire indicative of a puncturing event or a rapid deflation event having occurred, or the tire having been exchanged.

16. A module as claimed in claim 15, wherein the module is operable to communicate a message therefrom that sensed data pertaining to the tire of the wheel being potentially unreliable on account of the abrupt depressurization.

17. A module as claimed in claim 1 wherein the module is operable to also respond with data indicative of expected characteristics of the wheel to which the module is mounted in operation.

18. A module as claimed in claim 1, wherein the module is operable to monitor a tampering event applied to the wheel.

19. A method of validation of data relevant to the functional status of a tire stored in a module mounted in a wheel, wherein the following method steps are performed:

a) monitoring a pressure measured by a pressure sensor;

b) maintaining the data relevant to the functional status of the tire as valid as long as the pressure is maintained above a predetermined threshold value;

c) setting the data relevant to the functional status of the tire as invalid as soon as the pressure measured by the pressure sensor falls below the predetermined threshold value.

20. A method according to claim 19, wherein the field containing data relevant to the functional status of the tire includes a field containing record of samples of pressure measured by the pressure sensor, wherein the data processor is sets the data relevant to the functional status of the tire as invalid when the record of samples contains at least one sample below the predetermined threshold value.

21. A method according to claim 19, wherein the following further method steps are performed:

a1) storing record of samples of pressure measured by the pressure sensor in the field containing data relevant to the functional status of the tire,

c1) setting the data relevant to the functional status of the tire as invalid when the record of samples contains at least one sample below the predetermined threshold value.

22. A method according to claim 19, wherein the module contains a flag which can be set to represent “

VALID”

or “

INVALID” and

that the data processor changes the flag from “

VALID”

to “

INVALID”

as soon as the pressure measured by the pressure sensor falls below the predetermined threshold value.

23. A method according to claim 22, wherein the data processor is prevented to change the flag from “

INVALID”

to “

VALID”

unless a key code signal is received externally from the module.

24. A method according to claim 22, wherein the data processor changes the flag from “

INVALID”

to “

VALID”

upon reception of a key code signal externally from the module.

25. A method according to claim 19, wherein the data field containing data relevant to the functional status of the tire including one or more of the following data:

a) tire slip curves,

b) tire size.

26. A method according to claim 19, wherein the data field containing data relevant to the functional status of the tire furthermore including one or more of the following data:

c) tire age

d) a record of the distance the tire has been used,

e) a field containing record of samples of pressure measured by the pressure sensor,

f) a field containing record of samples of the temperature measured by a temperature sensor mounted on the wheel for monitoring the temperature of the tire, and that the data processor is operable to continuously or periodically update the data

27. A method according to claim 19, wherein the following method steps are performed:

(a) measuring the pressure using a pressure sensor of the module for generating a corresponding pressure signal;

(b) receiving the pressure signal at a data processor of the module, the data processor being coupled in communication with an associated data memory;

(c) generating a record the pressure as a function of time in the data memory for monitoring the wheel and its tire; and

(d) communicating information derived from the record via a wireless interface of the module for enable a condition of the wheel to be monitored externally to the module.

28. A method according to claim 19, including a further step of detecting depressurization events experienced by the wheel and an exchange of the tire and including corresponding information in the record.

29. A method according to claim 19, including a step of mounting the module at one or more locations on the wheel, the one or more locations including:

(a) on a hub of the wheel substantially at an axis of rotation of the wheel;

(b) on a hub of the wheel at a radial distance from the axis of rotation of the wheel;

(c) on a hub of the wheel in fluid communication with a filling valve of a tire of the wheel for sensing a pressure within the tire;

(d) within a tire of the wheel for sensing a pressure within the tire, the module being mounted to a peripheral surface of a hub of the wheel;

(e) within a tire of the wheel for sensing a pressure within the tire, the module being mounted to an inside side-wall surface of the tire for measuring flexural characteristics of the side-wall; and

(f) on an inside surface of a peripheral rim of the wheel for measuring acceleration thereat.

30. A method according to claim 19, wherein the module includes a temperature sensor for sensing a temperature thereat, the temperature sensor being operable to generate a temperature signal representative of the temperature for receipt at the data processor for at least one of recording in the data memory and communicating via the wireless interface externally to the module.

31. A method as claimed in claim 19, wherein the module includes at least one of:

(a) a strain gauge sensor for measuring flexure of the tire of the wheel, the strain gauge sensor being operable to generate a signal indicative of the flexure for receipt at the data processor for at least one of recording in the data memory and communicating via the wireless interface externally to the module;

(b) an accelerometer for measuring acceleration in at least one axis at a mounting location of the module on the wheel, the accelerometer being operable to generate a signal indicative of the acceleration for receipt at the data processor for at least one of recording in the data memory and communicating via the wireless interface externally to the module; and

(c) a magnetic sensor for measuring a magnetic field applied to the module, the module being operable to generate a signal indicative of the applied magnetic field to the data processor for at least one of recording in the data memory and communicating via the wireless interface externally to the module.

32. A method as claimed in claim 19, wherein the module is provided with a corresponding identification code for communicating to a processing arrangement external to the module, so that the processing arrangement is able to recognize the module when corresponding signal data has been sent therefrom and attribute the signal data to the module.

33. A method as claimed in claim 19, wherein the data processor is coupled to the data memory, and the module via its pressure sensor is operable to record the pressure within the tire of the wheel in relation to time as determined by a clock arrangement included within the module, and the processor is operable to monitor changes in the pressure with time to identify one or more of:

(a) a gradual leak of air or gas from the tire indicative of a need to recharge the tire with air or gas; and

(b) any abrupt depressurization of the tire indicative of a puncturing event or a rapid deflation event having occurred, or the tire having been exchanged.

34. A method as claimed in claim 33, including a step of communicating from the module a message that sensed data pertaining to the tire of the wheel being potentially unreliable on account of the abrupt depressurization.

35. A method as claimed in claim 30, including a step of monitoring using the module a tampering event applied to the wheel.

36. A method of detecting misuse of tires wherein a data processor is operable to continuously or periodically update data stored in a data field containing data relevant to the functional status of the tire,

the data field includes at least one of:

d) a record of the distance the tire has been used,

e) a field containing record of samples of pressure measured by the pressure sensor,

f) a field containing record of samples of the temperature measured by a temperature sensor mounted on the wheel for monitoring the temperature of the tyre;

validating the data fields by a method according to claim 19, and,

determining that a misuse of the tire has been present if validated data shows that the field containing record of samples of pressure measured by the pressure sensor contains data outside a set range or if the field containing record of samples of the temperature measured by a temperature sensor contains data above a threshold value.