Assistance method for adjusting the pressure of a tire fitted to a wheel mounted on a motor vehicle

Patent metadata

Field	Value
Publication number	US-9656522-B2
Application number	US-201414902751-A
Country	US
Kind code	B2
Filing date	Jun 26, 2014
Priority date	Jul 4, 2013
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

An assistance method for adjusting the pressure of a tire mounted on a wheel of a motor vehicle having an electronic module adapted to transmit, to an on-board central unit in the vehicle, signals including data representing the pressure of the associated tire, this assistance method includes, in the first place, during an action of adjusting the pressure of a tire, determining, after receiving a number n of initial measurement signals, where n≧2, the gradient or slope Cd of the straight line representing the variation of the measured value Pm(t) of the pressure as a function of time. Next, on receiving each subsequent measurement signal, the remaining time required to obtain the setpoint pressure Pc is deduced from the ratio |Pc-Pm(t)|/Cd, and, on the expiry of this remaining time, initiating a procedure for managing the cessation of the pressure adjustment, and signaling the end of the adjustment.

First claim

The invention claimed is:

1. An assistance method for adjusting the pressure of a tire mounted on a wheel of a motor vehicle equipped with an electronic module adapted to transmit, to an on-board central unit in said vehicle, signals comprising data enabling the pressure of the associated tire to be determined, said assistance method comprising the following procedures, during an action of adjusting the pressure of the tire of a wheel:
transmitting, by the electronic module fitted to this wheel, of a sequence of signals, called measurement signals, each comprising data for determining a measured value Pm(t) of the tire pressure,
if the measured value Pm(t) of the pressure corresponds to a predetermined value of setpoint pressure Pc, a procedure of managing the cessation of the pressure adjustment action, comprising a final step of signaling the end of said adjustment action,
initially, after the reception of a number n of initial measurement signals, where n≧2, the gradient or slope Cd of the straight line representing the variation of the measured value Pm(t) of the pressure as a function of time is determined, and then,
on reception of each subsequent measurement signal, the remaining time required to reach the setpoint pressure Pc is deduced from the ratio |Pc-Pm(t)|/Cd,
and, if this remaining time expires before the reception, or simultaneously with the reception, of a new measurement signal, the procedure for managing the cessation of the pressure adjustment action is initiated.

2. The assistance method as claimed in claim 1 , wherein:
each wheel is equipped with means for measuring the temperature of the air volume inside the tire,
in a preliminary step, a correspondence table is drawn up for each type of wheel fitted to the vehicle, this table:
comprising inputs consisting of initial temperatures T i , corresponding to temperatures measured inside a tire when an action of adjusting the pressure of this tire is initiated (t 0 ), and of final temperatures T f , corresponding to temperatures measured inside the tire when the action of adjusting the pressure of this tire is interrupted (t 1 ),
associating with each pair of temperatures (T i , T f ) a pressure value ΔP corresponding to the determined pressure variation, before stabilization, at the end of an adjustment action that started at an initial temperature T i and was interrupted at a final temperature T f ,

and, during each action of adjusting the pressure of a tire, the initial temperature T i is determined when this action of adjustment is initiated, and, when the setpoint pressure Pc is obtained, a procedure of managing the cessation of the action of adjusting the pressure is executed, which comprises:
measuring the final temperature T f , and determining, by consulting the correspondence table, the pressure value ΔP associated with the pair of temperatures (T i , T f ), and
causing the execution of the final step of signaling the end of said adjustment action, after a time lapse equivalent to ΔP/Cd following the instant at which the setpoint pressure Pc is obtained.

3. The assistance method as claimed in claim 2 , further comprising:
dividing the types of compressors that may be used for adjusting the pressure of a tire of a motor vehicle (V) into at least two categories, each characterized by a predetermined range of values of free air delivery,
drawing up a specific range of correspondence tables for each category of compressor,
and, during each action of adjusting the pressure of a tire, determining the category of the compressor used according to the value Cd of the slope.

4. The assistance method as claimed in claim 3 , for a motor vehicle having a plurality of transmitters positioned on the vehicle so that each wheel position is covered by the transmission area of one or two transmitters, each of these transmitters being controlled by the central unit so as to transmit signals requesting the transmission of predetermined data, such as, notably, an identification request signal, to each electronic module located in its transmission area, wherein, on the expiry of the remaining time before the reception of a new measurement signal, the central unit is programmed, on this expiry, to cause:
the transmission, by a transmitter whose transmission area covers the electronic module associated with the tire undergoing pressure adjustment, of at least one signal requesting the transmission of a measurement signal, and
the initiation of the procedure for managing the cessation of the pressure adjustment action, if the measured value of the pressure Pm(t) calculated on the basis of the data delivered by the measurement signal corresponds to the setpoint pressure Pc.

5. The assistance method as claimed in claim 1 , according to which the final step of signaling the end of the adjustment action consists in causing the activation of audible and/or visual means.

6. The assistance method as claimed in claim 2 , according to which the final step of signaling the end of the adjustment action consists in causing the activation of audible and/or visual means.

7. The assistance method as claimed in claim 3 , according to which the final step of signaling the end of the adjustment action consists in causing the activation of audible and/or visual means.

8. The assistance method as claimed in claim 4 , according to which the final step of signaling the end of the adjustment action consists in causing the activation of audible and/or visual means.

9. The assistance method as claimed in claim 1 , wherein the on-board central unit includes a microprocessor and incorporating an RF receiver equipped with an antenna for receiving the signals transmitted by the electronic module.

10. The assistance method as claimed in claim 1 , wherein there are four electronic modules.

11. The assistance method as claimed in claim 1 , wherein transmitters are controlled by the central unit.

12. The assistance method as claimed in claim 11 , wherein there are four transmitters, each transmitter being placed near a wheel position in such a way that said wheel position is covered by a transmission area of this transmitter only.

Assignees

• Continental Automotive France
• Continental Automotive Gmbh

Inventors

• Raoul Corine

Classifications

• B60C23/0406

  Alarms noticeable from outside the vehicle, e.g. indication in side mirror, front light or audible alarms (B60C23/0403, B60C23/0405 take precedence) · CPC title

• B60C23/002

  by monitoring conditions other than tyre pressure or deformation · CPC title

• B60C23/0484

  Detecting an ongoing tyre inflation · CPC title

• B60C23/0474 Primary

  Measurement control, e.g. setting measurement rate or calibrating of sensors; Further processing of measured values, e.g. filtering, compensating or slope monitoring · CPC title

• B60C23/0477

  Evaluating waveform of pressure readings · CPC title