Method and system for determining tire pressure imbalances
AssigneeGeneral Motors Corporation
InventorJames R. Rosseau
Life of this patent
Estimating the term…
Abstract
A tire deflation warning system is based solely on the measured distance traveled by each tire of a: vehicle. The vehicle is equipped with a sensor which generates pulses representative of the distance traveled by each wheel such as generated by an ABS brake system. The system accumulates the pulses in the controller to determine whether the vehicle is stable. If the vehicle is stable, it performs a test to cover individual tires, opposing diagonal tires or any combination of three tires using an average of the diagonal ratio. These tests are performed by utilizing the pulses generated by each wheel representing the distance traveled by the wheel.
Claims24
A method of detecting tire pressure imbalances in a set of tires of a vehicle, the vehicle having four wheels, a right front wheel, a left front wheel, a right rear wheel and a left rear wheel, each of the four wheels having a sensor generating a pulse for a predetermined amount of distance traveled by the respective wheel, said method comprising the steps of:
- initiating a calibration mode;
- accumulating a number of pulses generated by each sensor during a predetermined calibration time interval;
- storing the number of pulses generated by each sensor during a measured interval equal in length to the calibration interval into an individual account for each sensor in a storage device;
- computing a stability check using the number of pulses stored in the individual accounts, discarding the numbers stored in the individual accounts if the stability check is unsatisfactory;
- summing the number of pulses in each of the accounts for a comparison total for each measured interval not discarded;
- comparing the comparison total to the calibration standard;
- and
- triggering an alarm when the comparison total is less than the calibration standard for a predetermined number of measured intervals.
A tire pressure detection system for a vehicle having a plurality of wheels comprising:
- providing a pulse generating sensor for each wheel of the vehicle to generate a pulse sum for each wheel as each wheel rotates;
- adding the pulse sums from the pulse generating sensors of each wheel to generate a total sum of pulses for all the pulse generating sensors;
- comparing the total sum of pulses to a calibrated pulse sum;
- comparing the pulse sum of at least one wheel to an individual wheel calibrated pulse sum when the total sum of pulses is equal to the calibrated pulse sum;
- triggering an indicator when the pulse sum of the at least one wheel is not equal to the individual wheel calibrated pulse sum.
A method of detecting tire pressure imbalances in a set of tires of vehicle, the vehicle having four wheels, and each wheel having a sensor generating a pulse for a predetermined amount of distance traveled by the wheel, the method comprising:
- entering a calibration mode;
- accumulating a number of pulses from each sensor and adding the number of pulses from each sensor to generate a calibrated total pulse count in the calibration mode;
- storing the individual pulse sums of each said sensor used to generate the calibrated total pulse count as individual pulse sum calibration values;
- storing the calibrated total pulse count;
- exiting the calibration mode;
- accumulating a number of pulses from each sensor to generate operating individual pulse sums and adding the number of operating individual pulse sums to generate an operating pulse count;
- determining if the operating pulse count is equal to the calibrated total pulse count;
- comparing at least one of the operating individual pulse sums to the individual pulse sum calibration values when the operating pulse count is equal to the calibrated total pulse count;
- and
- triggering an indicator if at least one of the operating individual pulse sums is not equal to the individual pulse sum calibrations.
A system for detecting tire pressure imbalance in a vehicle comprising:
- a plurality of wheels coupled to the vehicle;
- a plurality of pulse generating sensors operatively coupled to said plurality of wheels, each said pulse generating sensor generating a pulse for a predetermined amount of distance traveled by each said wheel;
- a controller for receiving said pulses generated by said plurality of pulse generating sensors;
- wherein said controller accumulates individual pulse sums from each of said pulse generating sensors pulses to generate a sum of total pulses;
- wherein said controller stores said individual pulse sums and said sum of total pulses;
- wherein said controller compares said sum of total pulses to a calibrated pulse total;
- wherein when said sum of total pulses is equal to said calibrated pulse total, said controller compares at least one of said individual pulse sums to a calibrated individual pulse sum for a specific wheel;
- and
- wherein when at least one of said individual pulse sums is not equal to said calibrated individual:. pulse sum for a specific wheel an indicator will be triggered.
A system for detecting tire pressure imbalance comprising:
- a vehicle;
- a plurality of wheels coupled to said vehicle;
- a plurality of sensors operatively coupled to said plurality of wheels, each said sensor sensing one of said plurality of wheels, said sensors generating pulses indicative of distance traveled by each said wheel;
- a controller for receiving said pulses generated by said sensors;
- wherein said controller accumulates individual pulse sums from each of said pulse generating sensors pulses to generate a sum of total pulses;
- wherein said controller:stores said individual pulse sums and said sum of total pulses;
- wherein said controller compares said sum of total pulses to a calibrated pulse total;
- wherein when said sum of total pulses is equal to said calibrated pulse total, said individual pulse sums from at least two wheels are used to generate a ratio;
- wherein said ratio is compared to a calibrated ratio;
- and
- wherein an indicator is triggered when said ratio is not equal to a calibrated ratio.
A method of calibrating for tire pressure imbalances in a set of tires of vehicle, the vehicle having four wheels, and each wheel having a sensor generating a pulse for a predetermined amount of distance traveled by the wheel, the method comprising:
- entering a calibration mode;
- accumulating a number of pulses from each sensor and adding the number of pulses from each sensor to generate a calibrated total pulse count in the calibration mode;
- storing the individual pulse sums of each sensor used to generate the calibrated total pulse count as individual pulse sum calibration values;
- storing the calibrated total pulse count;
- and
- exiting the calibration mode.
A method of detecting tire pressure imbalances in a set of tires of vehicle, the vehicle having four wheels, and each wheel having a. sensor generating a pulse for a predetermined amount of distance traveled by the wheel, the method comprising:
- entering a calibration mode;
- accumulating a number of pulses from each sensor and adding the number of pulses from each sensor to generate a calibrated total pulse count in the calibration mode;
- storing the individual pulse sums of each sensor used to generate the calibrated total pulse count as individual pulse sum calibration values;
- generating at least one ratio of the individual pulse sum calibration values;
- storing the at least one. ratio of the individual pulse sum calibration values;
- storing the calibrated total pulse count;
- exiting the calibration mode;
- accumulating a number of pulses from each sensor to generate operating individual pulse sums and adding the number of operating individual pulse sums to generate an operating pulse count;
- determining if the operating pulse count is equal to the calibrated total pulse count;
- generating a ratio of operating individual pulse sums for at least two wheels;
- comparing the ratio of operating individual pulse sums to the at least one ratio of individual pulse sum calibration values for the at least two wheels when the operating pulse count is equal to the calibrated total pulse count;
- and
- triggering an indicator when the ratios are not equal.
Dependencies are inferred from the claim text.