Method for determining the speed of a wheel on a motor vehicle
First Claim
1. Method for determining the speed of a wheel on a motor vehicle, for which purpose an acceleration sensor is mounted on the wheel, wherein the frequency ω
- of an alternating signal produced by the influence of the gravitational acceleration g and contained in the acceleration signal supplied by the acceleration sensor is determined as the speed of the wheel, characterised in that for the purpose of distinguishing in this method between a right wheel and a left wheel of a vehicle, in which an acceleration sensor is provided on both wheels and both acceleration sensors are arranged on the wheels in equal mounting positions, the tangential acceleration b resulting from the motion state of the respective wheel is measured;
the sign of the tangential acceleration b is determined;
the frequency ω
of an alternating signal contained in the tangential acceleration signal and produced by the influence of the gravitational acceleration g is observed as the speed of the wheel;
when the speed varies over time the sign of the variation is determined; and
the product of the sign of the tangential acceleration b and the sign of the variation in speed of the respective wheel is formed.
5 Assignments
0 Petitions
Accused Products
Abstract
There is described a method for determining the speed of a wheel on a motor vehicle, for which purpose an acceleration sensor is mounted on the wheel. It is proposed according to the invention to measure the frequency ω or the period T of an alternating signal contained in the acceleration signal supplied by the acceleration sensor and produced by the influence of gravitational acceleration g. The method is suited for use in automatic tyre-pressure monitoring systems for assigning signals, that have been transmitted by radio from a wheel-mounted electronic module, to a particular wheel position and for controlling the transmission rate of a wheel-mounted electronic module as a function of the speed.
17 Citations
7 Claims
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1. Method for determining the speed of a wheel on a motor vehicle, for which purpose an acceleration sensor is mounted on the wheel, wherein the frequency ω
- of an alternating signal produced by the influence of the gravitational acceleration g and contained in the acceleration signal supplied by the acceleration sensor is determined as the speed of the wheel, characterised in that for the purpose of distinguishing in this method between a right wheel and a left wheel of a vehicle, in which an acceleration sensor is provided on both wheels and both acceleration sensors are arranged on the wheels in equal mounting positions,
the tangential acceleration b resulting from the motion state of the respective wheel is measured;
the sign of the tangential acceleration b is determined;
the frequency ω
of an alternating signal contained in the tangential acceleration signal and produced by the influence of the gravitational acceleration g is observed as the speed of the wheel;
when the speed varies over time the sign of the variation is determined; and
the product of the sign of the tangential acceleration b and the sign of the variation in speed of the respective wheel is formed. - View Dependent Claims (3, 5)
- of an alternating signal produced by the influence of the gravitational acceleration g and contained in the acceleration signal supplied by the acceleration sensor is determined as the speed of the wheel, characterised in that for the purpose of distinguishing in this method between a right wheel and a left wheel of a vehicle, in which an acceleration sensor is provided on both wheels and both acceleration sensors are arranged on the wheels in equal mounting positions,
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2. Method for determining the reciprocal value of the speed of the wheel on a vehicle, for which purpose an acceleration sensor is mounted on the wheel, wherein the period T of an alternating signal produced by the influence of the gravitational acceleration g and contained in the acceleration signal supplied by the acceleration sensor is determined as the reciprocal value of the speed of the wheel, characterised in that for the purpose of distinguishing in this method between a right wheel and a left wheel of a vehicle, in which an acceleration sensor is provided on both wheels and both acceleration sensors are arranged on the wheels in equal mounting positions,
a tangential acceleration b resulting from the motion state of the respective wheel is measured; -
the sign of the tangential acceleration b is determined;
the period T of an alternating signal contained in the tangential acceleration signal and produced by the influence of the gravitational acceleration g is observed;
when the period T varies over time the sign of the variation is determined; and
the product of the sign of the tangential acceleration b and the sign of the variation of the period T of the respective wheel is formed. - View Dependent Claims (4)
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6. Method for determining the speed of a wheel on a motor vehicle, for which purpose an acceleration sensor is mounted on the wheel, wherein the frequency ω
- of an alternating signal produced by the influence of the gravitational acceleration g and contained in the acceleration signal supplied by the acceleration sensor is determined as the speed of the wheel, characterised in that when applying this method to a system for monitoring and signalling by radio any pressure change in pneumatic tyres of wheels on vehicles, which system is mounted on the respective wheel and comprises
a current source, an acceleration sensor for determining the speed of the wheel, a pressure sensor measuring the tyre pressure at first time intervals, and a transmitter that transmits an information on the measured tyre pressure to a receiver located in the vehicle at second time intervals, that are longer than or equal to the first time intervals, the first time intervals are controlled in dependence on the speed ω
of the respective wheel.
- of an alternating signal produced by the influence of the gravitational acceleration g and contained in the acceleration signal supplied by the acceleration sensor is determined as the speed of the wheel, characterised in that when applying this method to a system for monitoring and signalling by radio any pressure change in pneumatic tyres of wheels on vehicles, which system is mounted on the respective wheel and comprises
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7. Method for determining the reciprocal value of the speed of a wheel on a motor vehicle, for which purpose an acceleration sensor is mounted on the wheel, wherein the period T of an alternating signal produced by the influence of the gravitational acceleration g and contained in the acceleration signal supplied by the acceleration sensor is determined as the reciprocal value of the speed of the wheel, characterised in that when applying this method to a system for monitoring and signalling by radio any pressure change in pneumatic tyres of wheels on vehicles, which system is mounted on the respective wheel and comprises
a current source, an acceleration sensor for determining the speed of the wheel, a pressure sensor measuring the tyre pressure at first time intervals, and a transmitter that transmits an information on the measured tyre pressure to a receiver located in the vehicle at second time intervals, which are longer than or equal to the first time intervals, the first time intervals are controlled in dependence on the reciprocal value T of the speed ω - .
Specification