MOTOR VEHICLE TIRE PRESSURE MONITORING AND ADJUSTMENT SYSTEM AND MOTOR VEHICLE INCLUDING SUCH A SYSTEM

Abstract

The invention relates to a system (1) for monitoring and adjusting the pressure of at least one tire (3) of a motor vehicle, said system (1) comprising at least: – a tire (3); – a device for emitting acoustic waves (5) on and / or in said tire; – an acoustic sensor (7) for the acoustic waves emitted by said emitting device (5); – a device for adjusting the tire pressure; said system (1) being configured to evaluate, by means of the emitting device (5) and the sensor (7), the condition and / or pressure of the tire (3), and to modify the pressure of the tire (3), via the adjustment device (9), according to the condition and / or pressure of the tire (3). [Fig. 1]

Description

Title of the invention: SYSTEM FOR MONITORING AND ADJUSTING THE TIRE PRESSURE OF A MOTOR VEHICLE AND MOTOR VEHICLE COMPRISING SUCH A SYSTEM

[0001] The present invention relates to the field of motor vehicles, and more particularly to the field of monitoring the condition and / or pressure of at least one tire of a motor vehicle.

[0002] Monitoring the condition of a motor vehicle tire is generally carried out by measuring the pressure of said tire, for example by means of a pressure sensor housed in it.

[0003] Unfortunately, this type of monitoring device does not provide any information on the condition of the tire, i.e., its level of wear, defects, and / or damage that the tire may have sustained during use. Thus, only damage resulting in a leak, and therefore a drop in tire pressure, is detectable by a pressure sensor located in the tire.

[0004] Furthermore, in the case of electric vehicles, tire pressure is of great importance. Indeed, a tire that is not properly inflated for its condition can lead to excessive electrical consumption and thus reduce the range of the electric vehicle.

[0005] It is therefore necessary to find a system to improve the monitoring of the condition of the tires and / or their pressure level in order to allow an adjustment of the tire pressure accordingly and thus optimize the tire pressure to reduce the rolling resistance of the vehicle, thereby reducing the electrical or gasoline consumption of the vehicle, as well as tire wear, while reducing the safety risks associated with underinflated or worn tires.

[0006] The present invention thus aims to remedy at least one of the aforementioned drawbacks by proposing a new type of system for monitoring and adjusting the pressure of at least one motor vehicle tire, said system comprising at least: - a tire; - a device for emitting acoustic waves on and / or in said tire; - an acoustic sensor for the acoustic waves emitted by said emitting device; - a device for adjusting the tire pressure; said system being configured to evaluate, by means of said emission device and sensor, the condition and / or pressure of the tire, and to modify the tire pressure, by means of the adjustment device, according to the condition and / or pressure of the tire.

[0007] The system according to the invention makes it possible to determine the condition and / or pressure of a vehicle tire, at start-up and / or while driving, continuously or intermittently, and to adjust the tire pressure accordingly, thus making it possible to solve tire pressure management problems, thereby optimizing tire contact with the road, and thus reducing rolling resistance and improving the vehicle's energy efficiency, while increasing vehicle safety and tire durability.

[0008] The system also finds advantageous application in the field of electric vehicles, in particular by increasing the range of such vehicles, reducing operating and maintenance costs, and improving the user experience.

[0009] According to one possible characteristic, the acoustic waves emitted by said device are Rayleigh and / or Lamb waves.

[0010] Acoustic waves, such as ultrasonic waves, emitted by the wave-emitting device are advantageously configured to emit: - Rayleigh waves, which are surface waves that propagate mainly on the surface of solids, and which are sensitive to surface changes, such as those caused by pressure and / or wear, Rayleigh waves are thus suitable for detecting variations in tire pressure and damage to its surface; - Lamb waves, which are guided waves propagating in solids (preferably thin), such as the material constituting a tire, are thus effective in detecting internal variations in thickness of the material constituting a tire, variations for example caused by pressure variations and / or internal wear of the tire.

[0011] According to another possible feature, said at least one adjustment device includes a compressor and / or a valve configured to adjust (dynamically) the tire pressure. Advantageously, said at least one adjustment device is configured to increase and / or decrease the tire pressure, thus allowing a change in tire pressure as soon as the condition and / or pressure value of the tire requires it. The adjustment device includes, for example, a compressor and / or a valve that are configured to be controlled by the system according to the invention as soon as the condition and / or pressure value of the tire are determined by means of acoustic waves, thus allowing proper real-time adjustment of the tires.

[0012] According to another possible characteristic, the acoustic wave emission device and the sensor are the same element, a piezoelectric type sensor. Advantageously, the emission device and the acoustic wave sensor are the same element, such as a piezoelectric sensor, reducing the costs of the system according to the invention and facilitating its implementation in a motor vehicle.

[0013] According to another possible feature, said system comprises at least two piezoelectric type sensors. The said system may include two or three piezoelectric type sensors depending on the mathematical method used to determine the state and / or pressure of the tire based on the acoustic waves received by the sensor(s). Thus, if there are two sensors, the method used is a so-called "Bayesian statistics" method, while if there are three sensors, the method used is a so-called "hyperbolic" method. The hyperbolic method is generally more accurate and suitable for working in situations where the geometry of the signals or the characteristics of the tires vary significantly, but therefore requires more sensors (and is therefore more expensive).

[0014] According to another possible feature, said system includes an alerting device configured to issue an alert based on the condition and / or pressure of the tire. Advantageously, the system includes a separate warning device and / or a (usually pre-existing) vehicle human-machine interface to indicate the tire condition and / or pressure value, thereby alerting the vehicle user in the event of a critical tire-related situation that could compromise their safety. The warning device can also inform the user of the tire condition and / or pressure value.

[0015] According to another possible feature, said system includes a control module configured to communicate with and control the acoustic wave emission device, the sensor, said emission device and the tire pressure adjustment device. Advantageously, the system includes a control module that communicates with and controls the various system components, enabling, among other things, the analysis of sensor data, preferably in real time, to determine the condition and / or pressure of the tire. The control module is, for example, a separate computer installed in the vehicle or the vehicle's on-board computer.

[0016] According to another possible characteristic, the acoustic waves have a frequency between 100 kHz and 1000 MHz.

[0017] The invention also relates to a method for monitoring and / or adjusting at least one motor vehicle tire, said method comprising the following steps: - emission of acoustic waves in and / or on said tire; - reception of said acoustic waves and determination of the state and / or pressure of the tire; - issuing an alert and / or adjusting the pressure of said tire according to the condition and / or pressure of the tire (determined previously).

[0018] The invention also relates to a motor vehicle, for example thermal, hybrid or electric, characterized in that said vehicle includes a system for monitoring and adjusting the pressure of at least one tire as defined above.

[0019] The invention will be better understood, and other objects, details, features and advantages thereof will become more apparent from the following description of a particular embodiment of the invention, given solely by way of illustration and not limitation, with reference to the accompanying drawings, in which: - Fig. 1 illustrates a very schematic view of a system for monitoring and adjusting the pressure of at least one tire according to the invention; - Fig. 2 illustrates a flowchart of a method for monitoring and adjusting the pressure of at least one tire according to the invention.

[0020] In the following description, the term "include" is synonymous with "include" and is not limiting in that it permits the presence of other elements in the vehicle, or the structure to which it relates. It is understood that the term "include" includes the terms "consist of".

[0021] Fig. 1 thus illustrates a very schematic view of a system 1 for monitoring and adjusting the pressure of at least one tire 3 intended to equip a motor vehicle, for example a thermal, hybrid or electric vehicle.

[0022] Said system 1 thus comprises at least: - the tire 3; - a device for emitting acoustic waves 5 on and / or in said tire; - an acoustic sensor 7 of the acoustic waves emitted by said emitting device 5; - a tire pressure adjustment device 9 3; - a control module 11 which is configured, on the one hand, to communicate and control the acoustic wave emission device 5, the sensor 7, said tire pressure adjustment device 9 and, on the other hand, to determine, based on the acoustic waves received by the sensor 7, the state and / or pressure of the tire 3.

[0023] In the embodiment of the invention described herein, said at least one acoustic wave emission device 5 and sensor 7 are the same element, a piezoelectric type sensor, but these can also be separate elements.

[0024] Thus, said at least one piezoelectric sensor 5 is configured to emit and receive acoustic waves in the ultrasonic range, i.e. having for example a frequency between 100 kHz and 1000 MHz.

[0025] Advantageously, said system 1 comprises two or three piezoelectric type sensors 5 disposed in and / or on the tire 3 so as to emit acoustic waves in and / or on the tire 3.

[0026] The acoustic waves emitted by the sensor(s) 5 are advantageously progressive waves of at least one of the following two types: - Rayleigh waves which are surface waves which propagate mainly on the surface of solids, and which are sensitive to surface changes, such as those caused by pressure and / or wear, Rayleigh waves making it possible to detect variations in the pressure of the tire 3 and damage to the surface of said tire 3; - Lamb waves which are guided waves propagating in solids (preferably thin), such as the material constituting the tire 3, Lamb waves making it possible to detect internal variations in thickness of the material constituting the tire 3, variations for example caused by variations in pressure and / or internal wear of said tire 3.

[0027] The adjustment device 9 is, for its part, configured to adjust the pressure of the tire 3, under the control of the control module 11, according to the condition and / or pressure of the tire 3.

[0028] Thus, the adjustment device 9 may advantageously include a compressor and / or a valve which are configured to increase and / or decrease the pressure of the tire 3.

[0029] The control module 11, for example, is a separate computer installed in the vehicle or the on-board computer of said vehicle, and is configured to analyze the data from the sensor 5, preferably in real time, in order to determine the condition and / or pressure of the tire 3.

[0030] It should be noted that if system 1 comprises: - two sensors 5, the mathematical method implemented by module 11 to determine the state and / or pressure of the tire 5 as a function of the acoustic waves received by the sensors 5 is a method called "Bayesian statistics"; - three sensors 5, the mathematical method implemented by module 11 to determine the state and / or pressure of the tire 5 as a function of the acoustic waves received by the sensors 5 is a so-called "hyperbolic" method.

[0031] Furthermore, the sensors 5 can be located on the surface of the tire 3 to detect Rayleigh waves, which propagate along the surface of the tire 3 (waves that are sensitive to surface anomalies such as cracks and / or tread wear). However, the sensors 5 can also be located (or housed) inside the tire 3, such sensors 5 being more suitable for detecting Lamb waves, which propagate through the material of said tire 3 (and can detect internal defects such as delamination or changes in density).

[0032] Thus, it is advantageous to have sensors 5 located on and in the tire 5 for more precise and exhaustive monitoring of the tire 3, but it is nevertheless possible to have sensors 5 only on the tire 3 or only housed in the tire 3 (this according to the specific needs of the system and / or cost constraints).

[0033] Said system 1 may further include an alert device 13 (configured to issue an alert based on the condition and / or pressure of the tire 3. The alert device 13 may be a separate device and / or a (pre-existing) human-machine interface, such as an on-board display located in the vehicle's passenger compartment, to indicate the condition and / or pressure value of the tire 3, and thus alert the vehicle user if the tire 3 represents a danger or a risk to their safety.

[0034] Said system 1 is therefore advantageously configured to control the emission of acoustic waves when the vehicle is starting and / or when the vehicle is in motion.

[0035] Fig. 2 illustrates a flowchart of a method 100 for monitoring and / or adjusting at least one tire 3 that can be implemented by the system 1.

[0036] Said process 100 thus comprises the following steps: - emission of acoustic waves Sb by the emission device 5, in and / or on said tire 3; - reception of said acoustic waves S2, by the sensor 7, and determination S3, by the control module 11, of the state and / or pressure of the tire 3; - issuing an alert S4 and / or adjusting the pressure S5, using the adjustment device 9, of said tire 3 according to the condition and / or pressure of tire 3.

[0037] Thus, Rayleigh and / or Lamb waves propagate respectively in (i.e., the material constituting the tire) and / or on the surface of the tire 3, the sensor 7 receiving an acoustic wave exhibiting modifications which depend on the state and / or pressure of the tire 3.

[0038] The data retrieved via the sensors 7 are analyzed and processed using mathematical methods by the control module 11, in order to determine the state and / or pressure of the tire 3.

[0039] Thus, based on the data analysis, the control module 11 sends an alert and / or the result of the analysis, displayed via the human-machine interface 13, to the vehicle user, but also commands to the compressor and / or the valve to adjust the pressure of the tire 3. The alert thus displayed by the human-machine interface makes it possible to signal to the vehicle user significant anomalies on the tire 3, such as pressure leaks or excessive tire wear, so that said user can take the necessary corrective measures.

[0040] System 1 is also configured so that the actions implemented to change the pressure of the tire 3 are displayed on the human-machine interface 13 to inform the vehicle user.

[0041] The system 1 can therefore implement the process 100 at the start of the vehicle, and thus optimize the level of pressure of the tire 3, or implement it when the vehicle is in motion, in order to respond to the alterations suffered by the tire 3 and / or to the variations in the pressure values ​​of the tire 3 during use (change of temperature due to the environment, damage, etc.).

[0042] In an unrepresented embodiment of the invention, the acoustic waves used to evaluate the state and / or pressure of the tire are Love waves.

Claims

Demands

1. System (1) for monitoring and adjusting the pressure of at least one tire (3) of a motor vehicle, said system (1) comprising at least: - a tire (3); - a device for emitting acoustic waves (5) on and / or in said tire; - an acoustic sensor (7) for the acoustic waves emitted by said emitting device (5); - a device for adjusting the tire pressure (9); said system (1) being configured to evaluate, by means of the emitting device (5) and the sensor (7), the condition and / or pressure of the tire (3), and to modify the pressure of the tire (3), by means of the adjustment device (9), according to the condition and / or pressure of the tire (3).

2. System (1) according to the preceding claim, characterized in that the acoustic waves emitted by said device (5) are Rayleigh and / or Lamb waves.

3. System (1) according to any one of the preceding claims, characterized in that said at least one adjustment device comprises a compressor and / or a valve configured to adjust the pressure of the tire (3).

4. System (1) according to any one of the preceding claims, characterized in that the acoustic wave emission device (5) and the sensor (7) are a single element, a piezoelectric type sensor.

5. System (1) according to the preceding claim, characterized in that said system (1) comprises at least two piezoelectric type sensors.

6. System (1) according to any one of the preceding claims, characterized in that said system (1) comprises an alerting device (13) configured to issue an alert based on the condition and / or pressure of the tire (3).

7. System (1) according to any one of the preceding claims, characterized in that said system (1) comprises a control module (11) configured to communicate with and control the acoustic wave emission device (5), the sensor (7), said emission device (5) and said at least one tire pressure adjustment device (9) (3).

8. System (1) according to any one of the preceding claims, characterized in that the acoustic waves have a frequency between 100 kHz and 1000 MHz.

9. Method (100) for monitoring and / or adjusting at least one motor vehicle tire, said method (100) comprising the following steps: - emission of acoustic waves (S1) in and / or on said tire; - reception of said acoustic waves (S2) and determination (S4) of the condition and / or pressure of the tire; - issuance of an alert (S5) and / or adjustment of the pressure (S6) of said tire (3) according to the condition and / or pressure of the tire (3).

10. Motor vehicle, characterized in that said vehicle comprises a system (1) for monitoring and adjusting the pressure of at least one tire (3) according to any one of claims 1 to 8.