WO2012136354A1

WO2012136354A1 - Method and apparatus for visual and/or acoustic information of a vehicle user about tire pressure in vehicle wheels during filling operation

Info

Publication number: WO2012136354A1
Application number: PCT/EP2012/001480
Authority: WO
Inventors: Charles-Henri DE CATUELAN; Elie Abi Chaaya; Douglas C. Campbell
Original assignee: Johnson Controls Automotive Electronics Sas
Priority date: 2011-04-06
Filing date: 2012-04-03
Publication date: 2012-10-11

Abstract

The present invention refers to a method and a device for providing a user with visual and/or acoustic information about the actual tire pressure in a vehicle wheel during tire filling by measuring the actual tire pressure in a wheel of the vehicle using a pressure sensor provided in the wheel, analyzing the measured tire pressure data by a control unit and generating visual and/or acoustic information when the control unit detects that actual tire pressure reaches a predefined threshold during tire filling.

Description

DESCRIPTION

TITLE

Method and apparatus for visual and/or acoustic information of a vehicle user about tire pressure in vehicle wheels during filling operation

BACKGROUND

The invention relates to a method and an apparatus for providing a vehicle user with a visual and/or acoustic information about a tire pressure of the wheels of the vehicle during tire filling.

In the prior art, a tire pressure is displayed to the user only inaccurately with large tolerances or deviations. The actual tire pressure is often monitored to the person filling up the tire pressure by means of imprecise analog displays, for instance.

SUMMARY

It is therefore an object of the present invention to provide an improved method and device for providing a vehicle user with visual and/or acoustic information about the tire pressure in a corresponding vehicle wheel during tire filling.

The object of the present invention is achieved by a method and a device for providing a person e.g. the vehicle user or vehicle driver, with visual and/or acoustic information about the actual tire pressure in a corresponding vehicle wheel during tire filling, wherein a pressure sensor is provided for each wheel of the vehicle for measuring the tire pressure of the corresponding wheel and transferring the tire pressure data to a control unit of the car and wherein the person is provided with a visual and/or acoustic information when the actual tire pressure reaches a predefined threshold during tire filling. It is herewith advantageously possible for the person inflating the tire to easily and accurately adjust the correct tire pressure which is e.g. predetermined by the tire or car manufacturer.

The rolling resistance of the tire and therefore also the fuel consumption can be reduced by setting up the correct tire pressure. According to a preferred embodiment of the present invention, the device comprises at least one temperature sensor, wherein the visual and/or acoustic information is generated in dependency of a temperature signal provided by the temperature sensor.

It is conceivable that either the threshold is adjusted in dependency of the temperature signal or the actual tire pressure is determined in dependency of a pressure signal measured by the tire pressure sensor as well as in dependency of the temperature signal. In particular, the temperature sensor measures the temperature of the external environment of the car and/or the temperature of a certain tire.

Preferably, the device comprises one temperature sensor per tire, so that the temperature of each tire can be determined precisely. In particular, the temperature sensor is integrated into the pressure sensor. Alternatively, the device comprises a central temperature sensor to determine ambient temperature.

It is herewith advantageously possible to precisely determine the internal pressure of the tires by taking into account the corresponding actual temperature in the tire and/or at least the ambient temperature. In this manner changes in temperature which leads to pressure changes can be compensated.

Preferably, it is possible that tire temperature rise above ambient temperature could be estimated based on driving time and/or speed and/or lateral acceleration. It is herewith also possible to calculate the correct tire pressure for a certain temperature (where the tire is cold) in dependency of the measured ambient temperature. Particularly preferably, this estimate, combined with the ambient temperature measurement, could be used to calculate the correct cold tire pressure if the tires do not measure temperature directly.

For example, vehicle user often control and inflate the tire pressure of their vehicle after the vehicle has been used (e.g. driving to a petrol station for filling up the tires with pressurized air), so that the tires has already been warmed up by driving when the pressure is adjusted. However, in many cases, the car or tire manufacturers predetermine correct tire pressure values which only applies to tires which has not been warmed up. Furthermore, temperature changes caused by different seasons can be compensated. By utilizing only the temperature information transmitted by the tern- 2012/001480

3 perature sensor measuring the tire temperature or combining it with the ambient temperature, the control unit calculates the correct warm tire pressure. This is used for generating the visual and/or acoustic information, so that when the tire cools down, the tire is at the correct temperature.

These and other characteristics, features and advantages of the present invention will become apparent from the following description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. The description is given for the sake of example only, without limiting the scope of the invention. The reference figures quoted below refer to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 illustrates schematically a device for accomplishing a method according to an exemplary first embodiment of the present invention.

Figure 2 illustrates schematically a device for accomplishing a method according to an exemplary second embodiment of the present invention.

DETAILED DESCRIPTION

The present invention will be described with respect to particular embodiments and with reference to certain drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and are non-limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn on scale for illustrative purposes.

Where an indefinite or definite article is used when referring to a singular noun, e.g. "a", "an", "the", this includes a plural of that noun unless something else is specifically stated.

Furthermore, the terms first, second, third and the like in the description and in the claims are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodi- merits of the invention described herein are capable of operation in other sequences than described of illustrated herein.

In figure 1 , a device 1 for accomplishing a method according to a first embodiment of the present invention is schematically illustrated. This device 1 comprises at least one tire pressure sensor 2 for each wheel 3 of the vehicle 4 which is/are in particular assigned to the corresponding wheel 3. The device 1 further comprises a control unit 5 and means for acoustic and/or visual information output 6, 7.

The tire pressure sensor 2 is provided in or at each wheel 3 in such a manner that the tire pressure sensor 2 determines the internal tire pressure of the wheel 3. The determined tire pressure is transmitted via a known wireless transmission methods to the control unit 5. A sensor-individual identification key is transmitted to the control unit 5 in addition to the tire pressure, so that the respective tire pressure sensors 2 of the vehicle 4 are distinguishable and that the determined tire pressure can be assigned to a certain wheel 3 in or by the control unit 5. In a first embodiment of the present invention, the internal tire pressure of the wheel 3 is detected and transmitted by the tire pressure sensor 2 continuously. The pressure information can be transmitted at predetermined intervals or due to a specific event such as changes in speed, acceleration, or tire pressure.

According to an alternative embodiment of the present invention, the tire pressure sensor 2 transmits the internal tire pressure of the wheel 3 only when the tire pressure is equal to or exceed a predetermined threshold value. A suchlike threshold represents a correct tire inflation pressure, which is predetermined by the car or tire manufacturer, for instance.

The control unit 5 is a conventional control unit and is preferably coupled to a bus system of the vehicle 4 which is not illustrated. The control unit 5 can be configured as a separate control unit or be integrated into an existing control unit of the vehicle 4.

The identification keys of all tire pressure sensors 2 provided in the vehicle 4 are stored in the control unit 5, so that a certain tire pressure sensor 4 can be determined on the basis of the identification key and that preferably also the position of the tire nrnociirn O II _ -J - tions of the different tire pressure sensors 4 are stored in the control unit 5. It is herewith possible that a tire pressure transmitted by a tire pressure sensor 2 to the control unit 5 is assigned to a certain wheel 3 of the vehicle 4.

Furthermore, a predetermined threshold value of the tire internal pressure can be stored in the control unit 5, which represents the correct tire pressure e.g. predetermined by the car or tire manufacturer. The predetermined threshold could be programmed by the manufacturer at the assembly plant or at a dealership. The predetermined threshold could also be stored in another module and communicated to the control unit 5. The user could adjust the predetermine threshold in case different tires have been installed on the vehicle which require a different cold temperature setting. This could be done through the switches, instrument cluster, or information display and communicated to the control unit.

If the control unit 5 detects that the tire internal pressure is equal to or exceed the threshold value, means of acoustic and/or visual information output 6, 7 are activated. Here, the means of acoustic and/or visual information output 6, 7 can be activated together or separately. According to an alternative embodiment, means for either acoustic or visual information output 6, 7 are provided in the vehicle 4.

The means of acoustic and/or visual information output 6, 7 are electrically coupled to the control unit 5, for example by means of a conventional bus system.

For example, the means of acoustic information output 6 comprises a conventional buzzer, a warning bell, an alarm horn or a car horn. In an alternative embodiment, a warning sound or an acoustic warning is generated by means of speakers of a conventional car information and entertainment system, whereby the speakers are located in the interior of the vehicle 4.

The means for visual information output 7 comprises e.g. conventional waming lamps emitting a flash of light or a steady light or provided as alert means of a conventional instrument cluster or information display (also referred to as combined instrument) arranged in the interior of the vehicle 4. According to an alternative embodiment, at least a warning lamp provided on an outer wall or edge of the vehicle 4 is arranged in such a manner that the warning lamp is always located inside the field of view of a vehicle user who is filling up a certain tire. By means of the acoustic and/or visual information output 6, 7 the vehicle user is able to easily set up the correct internal tire pressure during filling of each tire.

According to a preferred embodiment, it is possible that tire temperature rise above ambient temperature could be estimated based on driving time and/or speed and/or lateral acceleration. The correct tire pressure is calculated for a certain temperature (where the tire is cold) in dependency of the measured ambient temperature. Particularly preferably, this estimate, combined with the ambient temperature measurement, could be used to calculate the correct cold tire pressure if the tires do not measure temperature directly.

In figure 2, a device 1 for accomplishing a method according to an exemplary second embodiment of the present invention is schematically illustrated, wherein in principle the first embodiment and the second embodiment are identical. In contrast, the device 1 according to the second embodiment comprises four temperature sensors 8 each integrated into one of the tire pressure sensors 2 in order to measure the temperature of each wheel 3.

Furthermore, the device 1 comprises a central temperature sensor 9 in order to determine the ambient temperature of the vehicle 4. The control unit 5 adjusts the threshold for generating the acoustic and/or visual information output 6, 7 in dependency of the temperature provided by the temperature sensors 8, 9.

The visual and/or acoustic information 7,8 is generated based on the recalculated threshold value in such a manner that the internal pressure of the tires will be at the correct temperature, if the temperature of the tires cools down or reaches a common reference value.

It is herewith for the vehicle user advantageously possible to set up the correct internal pressure independently from the actual tire or ambient temperature, even if the correct temperature value predetermined by the car or tire manufacturer applies to a reference temperature which strongly deviates from the actual tire temperature. REFERENCE SIGNS

1 device

2 tire pressure sensor

3 wheel

4 vehicle

5 control unit

6 acoustic information output

7 visual information output

8 temperature sensor 9 central temperature sensor

Claims

PATENT CLAIMS

1. A method for providing a user with visual and/or acoustic information (6, 7) about the actual tire pressure in a vehicle wheel (3) during tire filling comprising the following steps:

- Measuring the actual tire pressure in a wheel (3) of the vehicle (4) using a pressure sensor (2) provided in the wheel (3);

- Analyzing the measured tire pressure data by a control unit (5);

- Generating visual and/or acoustic information (6, 7) when the control unit (5) detects that actual tire pressure reaches a predefined threshold during tire filling.

2. Method according to claim 1 , wherein the visual and/or acoustic information (6, 7) is generated in dependency of a temperature signal provided by a temperature sensor (8, 9).

3. Method according to claim 2, wherein the temperature sensor (9) measures the ambient temperature of the vehicle (4) and/or wherein the temperature sensor (8) measures the temperature in the vehicle wheel (3).

4. Method according to one of the claims 2 or 3, wherein the threshold is adjusted in dependency of the temperature signal.

5. Method according to one of the claims 2 to 4, wherein the correct tire pressure is determined in dependency of the measured pressure data and in dependency of the measured temperature data.

6. Method according to claim 5, wherein the correct tire pressure is determined in dependency of the measured actual temperature in the tire and in dependency of the measured ambient temperature.

7. Device (1 ) for providing a user with visual and/or acoustic information (6, 7) about the actual tire pressure in a vehicle wheel (3) during tire filling comprising - at least one pressure sensor (2) in a wheel (3) of the vehicle (4) for measuring the actual tire pressure of the wheel (3),

- a control unit (5) for analyzing the measured tire pressure data and

- means for providing visual and/or acoustic information (6, 7) when the control unit (5) detects that actual tire pressure reaches a predefined threshold during tire filling.

8. Device (1 ) according to claim 7, wherein the device (1 ) comprises at least one temperature sensor (8) for measuring the temperature in the vehicle wheel (3), wherein the visual and/or acoustic information (6, 7) is generated in dependency of a temperature signal provided by the temperature sensor (8).

9. Device (1 ) according to claim 8, wherein the temperature sensor (8) is integrated into the pressure sensor (2).

10. Device (1) according to one of the claims 7 to 9, wherein the device (1 ) comprises a central temperature sensor (9) to determine ambient temperature of the vehicle (4).