METHOD FOR DETERMINING THE LENGTH OF THE FOOTPRINT ON THE GROUND OF A TIRE OF A WHEEL OF A VEHICLE

• US 20090205414A1
• Filed: 02/13/2009
• Published: 08/20/2009
• Est. Priority Date: 02/15/2008
• Status: Active Grant

• Current Assignee: Continental Automotive France (Continental AG)
• Original Assignee: Continental Automotive France (Continental AG)
• Inventors: BOUKRAA, Riad, VASSILIEFF, Youri
• Granted Patent: US 7,942,047 B2
• Time in Patent Office: Days
• US Class Current: 73/146
• CPC Class Codes: B60C 23/066 by monitoring wheel-centre to ground distance
• CPC Class Codes: B60T 2240/04 Tire deformation
• CPC Class Codes: G01B 7/14 for measuring distance or clearance between spaced objects or spaced apertures G01B7/30 takes precedence
• CPC Class Codes: G01M 17/02 Tyres

Abstract

The invention relates to a method for determining, while a vehicle is traveling, the length of the footprint on the ground of a tire (7) comprising a metal belt, fitted to a rim (6) of a wheel of said vehicle. According to the invention, this method consists in mounting a magnetic sensor (16) on the rim (6) and in analyzing the signal representing the magnetic field measured by said magnetic sensor, so as to detect the variations of the magnetic field resulting from the deformations sustained by a circumferential zone of the tire (7) situated opposite the magnetic sensor (8) when, respectively, said circumferential zone enters into contact with the ground and leaves the ground.

Claims

1. A method for determining, while a vehicle (1) is traveling, the length of the footprint on the ground of a tire (7) comprising a metal belt, fitted to a rim (6) of a wheel (2-5) of said vehicle, a magnetic sensor (16) on the rim (6) and said method consisting in analyzing the signal representing the magnetic field measured by said magnetic sensor, so as to detect the variations of the magnetic field resulting from the deformations sustained by a circumferential zone of the tire (7) situated opposite the magnetic sensor (16), characterized in that it analyzes the signal representative of the magnetic field measured by said magnetic sensor, when, respectively, said circumferential zone enters into contact with the ground and leaves the ground in order to determine the footprint on the ground of the tire.

2. The determination method as claimed in claim 1, characterized in that the magnetic sensor (16) is positioned so that said magnetic sensor has an axis of maximum sensitivity extending parallel to the axis of rotation of the wheel (2-5).

3. The determination method as claimed in claim 1, characterized in that the metal belt of the tire (7) is first magnetized in at least the circumferential zone of said tire intended to be facing the magnetic sensor (16).

4. The determination method as claimed in claim 3 taken together, characterized in that the metal belt of the tire (7) is magnetized along an axis of magnetization parallel to the axis of maximum sensitivity of the magnetic sensor (16).

5. The determination method as claimed in claim 3, characterized in that the metal belt of the tire (7) is first magnetized in the only circumferential zone of said tire placed facing the magnetic sensor (16), by means of an electromagnet, and after the tire (7) has been mounted on a rim (6) fitted with the magnetic sensor (16).

6. The determination method as claimed in claim 1, characterized in that the magnetic sensor (16) is incorporated into an electronic module (8-11) of a system for monitoring the operating parameters of a wheel (2-5) of the vehicle (1).