Low tire warning system
First Claim
1. A tire profile monitoring apparatus including at least one telemetry means adapted to be mounted adjacent a pneumatic tire of a vehicle, said telemetry means comprising:
- transducer means for sensing an abnormal tire profile and for producing electric pulses in response to said detected abnormal profile;
accumulator means for accumulating said transducer pulses, said accumulator means operatively connected with transducer means, said accumulator means comprising counting means for counting an indicia of the number of transducer pulses received, said counting means causing an enable signal upon counting to a predetermined number;
encoder means for producing a modulating signal;
transmitting means for transmitting modulated radio signals, said transmitting means operatively connected with encoder means for receiving said modulating signal for producing modulated radio signals, said transmitting means being enabled by said enable signal, said transmitting means being operatively connected with said accumulator means for receiving said enable signal whereby said transmitting means transmits a modulated radio signal when the counting means counts the predetermined number of counts.
4 Assignments
0 Petitions
Accused Products
Abstract
An abnormal tire profile indicating system comprising a telemetry unit mounted on each wheel of a vehicle and a central receiver. Each telemetry unit comprises a piezoelectric transducer which is deflected with each wheel revolution when the tire profile is low. Deflecting the transducer produces an electric pulse. The transducer pulses are accumulated on a charge storage capacitor until a threshold level is reached. A threshold level detector causes a transistor connected to the capacitor to become conductive when the threshold level is exceeded. This transistor, when conductive, powers a counter, an encoder and a transmitter. The counter counts the number of times the transistor become conductive and produces an enable signal when a predetermined number is counted. The enable signal enables the transmitter to receive an encoded signal from the encoder and modulates a radio carrier frequency with the encoder signal. The modulated radio signals are received from each telemetry unit by the central receiver. The central receiver produces an indicia of the occurrence of the abnormal tire profile at one or more of the wheels. The counter limits the transmitter to transmitting only after a sufficient number of detections to assure that the sensed conditions are due to a low profile rather than rough roads or extraneous signals. Further, the counter allows radio transmissions only after a sufficient number of wheel revolutions to meet FCC requirements on the periodicity of transmissions.
36 Citations
11 Claims
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1. A tire profile monitoring apparatus including at least one telemetry means adapted to be mounted adjacent a pneumatic tire of a vehicle, said telemetry means comprising:
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transducer means for sensing an abnormal tire profile and for producing electric pulses in response to said detected abnormal profile; accumulator means for accumulating said transducer pulses, said accumulator means operatively connected with transducer means, said accumulator means comprising counting means for counting an indicia of the number of transducer pulses received, said counting means causing an enable signal upon counting to a predetermined number; encoder means for producing a modulating signal; transmitting means for transmitting modulated radio signals, said transmitting means operatively connected with encoder means for receiving said modulating signal for producing modulated radio signals, said transmitting means being enabled by said enable signal, said transmitting means being operatively connected with said accumulator means for receiving said enable signal whereby said transmitting means transmits a modulated radio signal when the counting means counts the predetermined number of counts. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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Specification