Method of detecting a deflated tire on a vehicle
First Claim
1. A method of detecting a partially deflated pneumatic tire on a vehicle having first, second, third and fourth tires, each of the tires being mounted on a first, second, third and fourth wheel, respectively, comprising sensing the angular velocity of each of the wheels by providing for each of the wheels, a pulse generator means for providing a single pulse for each turn of each of the wheels, selecting the first wheel and measuring the time for one rotation of the first wheel, after beginning the measuring for the first wheel similarly measuring the times of one rotation for each of the second, third and fourth wheels, storing the times, for rotation of each of the wheels for at least three rotations of each of the wheels and averaging the times to produce an average angular velocity value signal for each of the wheels, storing in a processor unit at least 3 successive average angular velocity value signals for each of the wheels and calculating by interpolating therein the angular velocity for each of the wheels at a predetermined time, so that the angular velocities of all of the wheels are known for the same time, processing the four signals in the processor unit which subtracts the sum of the signals from one pair of diagonally opposite wheels from the sum of the signals from the other pair of diagonally opposite wheels, and senses when the magnitude of the resulting value is in a range between 0.05% and 0.60% of the mean of the two sums, and, when the resulting value is in the range, operating a warning device to indicate at least one of the tires is partially or completely deflated.
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Accused Products
Abstract
A method of detecting a partially deflated pneumatic tire on a vehicle having four tires each mounted on a wheel comprising sensing the angular velocity of each wheel by providing for each wheel, a signal generator to provide a single signal or pulse for each turn of the wheel, characterized by selecting a first wheel and measuring the time for one rotation of that first wheel, after beginning the first measurement similarly measuring the times of rotation for each other wheel, storing the times for each of the wheels for at least three rotations of each wheel and averaging the times to produce an average angular velocity value for each wheel, processing the four signals in a processor unit which subtracts the sum of the signals from one pair of diagonally opposite wheels from the sum of the signals from the other pair of diagonally opposite wheels, sensing when the magnitude of the result is between 0.05% and 0.60% of the mean of the two sums and when it is operating a warning device to indicate a tire is partially or completely deflated.
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Citations
19 Claims
- 1. A method of detecting a partially deflated pneumatic tire on a vehicle having first, second, third and fourth tires, each of the tires being mounted on a first, second, third and fourth wheel, respectively, comprising sensing the angular velocity of each of the wheels by providing for each of the wheels, a pulse generator means for providing a single pulse for each turn of each of the wheels, selecting the first wheel and measuring the time for one rotation of the first wheel, after beginning the measuring for the first wheel similarly measuring the times of one rotation for each of the second, third and fourth wheels, storing the times, for rotation of each of the wheels for at least three rotations of each of the wheels and averaging the times to produce an average angular velocity value signal for each of the wheels, storing in a processor unit at least 3 successive average angular velocity value signals for each of the wheels and calculating by interpolating therein the angular velocity for each of the wheels at a predetermined time, so that the angular velocities of all of the wheels are known for the same time, processing the four signals in the processor unit which subtracts the sum of the signals from one pair of diagonally opposite wheels from the sum of the signals from the other pair of diagonally opposite wheels, and senses when the magnitude of the resulting value is in a range between 0.05% and 0.60% of the mean of the two sums, and, when the resulting value is in the range, operating a warning device to indicate at least one of the tires is partially or completely deflated.
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19. A method of detecting a partially deflated pneumatic tire on a vehicle having first, second, third and fourth tires, each of the tires being mounted on a first, second, third and fourth wheel, respectively, comprising sensing the angular velocity of each of the wheels by providing for each of the wheels, a pulse generator means for providing a single pulse for each turn of each of the wheels, selecting the first wheel and measuring the time for one rotation of the first wheel, after beginning the measuring for the first wheel similarly measuring the times of one rotation for each of the second, third and fourth wheels, storing the times for rotation of each of the wheels for at least three rotations of each of the wheels and averaging the times to produce an average angular velocity value signal for each of the wheels, storing in a processor unit at least 3 successive average angular velocity value signals for each of the wheels and calculating by interpolating therein the angular velocity for each of the wheels at a predetermined time, so that the angular velocities of all of the wheels are known for the same time, processing the four signals in the processor unit which subtracts the sum of the signals from one pair of diagonally opposite wheels from the sum of the signals from the other pair of diagonally opposite wheels, and senses when the magnitude of the resulting value is in a range between 0.05% and 0.60% of the mean of the two sums, and comparing in the processor unit the signal for each of the wheels in turn with the signals for each of the remaining wheels, to sense when one of the signals is different from the average of all four signals by more than 0.1% , and, when the resulting value is in the range and one of the sigals is different from the average of all four signals by more than 0.1%, operating a warning device to indicate at least one of the tires is partially or completely deflated.
Specification