Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
206 words
A system for detecting warning sounds external to a vehicle and producing a corresponding warning signal to a driver of a vehicle, said system comprising in combination: a. sound transducer means for receiving warning sound signals reflected from a roadway supporting said vehicle and producing an electrical audio frequency signal in response to said received warning sound signals, said sound transducer means being oriented downward to efficiently detect reflected warning sound signals approaching said vehicle from any lateral direction with respect to said vehicle while tending to block out detection of unreflected sound signals; b. audio amplifier means responsive to said audio frequency electrical signal for amplifying said audio frequency electrical signal; c. tone detector circuit means coupled to an output of said audio amplifier means for producing an output signal having a first level if the output signal produced by said audio amplifier is within a predetermined range of frequencies and a second level if said output of said audio amplifier means is not within said predetermined range of frequencies; and d. warning indicator means responsive to said tone detector circuit means for producing said warning signal in response to said first level, said warning signal being readily perceivable by the driver of said vehicle.
Claim 2
Independent Claim
206 words
A system for detecting warning sounds external to a vehicle and producing a corresponding warning signal to a driver of a vehicle, said system comprising in combination: a. sound transducer means for receiving warning sound signals reflected from a roadway supporting said vehicle and producing an electrical audio frequency signal in response to said received warning sound signals, said sound transducer means being oriented downward to efficiently detect reflected warning sound signals approaching said vehicle from any lateral direction with respect to said vehicle while tending to block out detection of unreflected sound signals; b. audio amplifier means responsive to said audio frequency electrical signal for amplifying said audio frequency electrical signal; c. tone detector circuit means coupled to an output of said audio amplifier means for producing an output signal having a first level if the output signal produced by said audio amplifier is within a predetermined range of frequencies and a second level if said output of said audio amplifier means is not within said predetermined range of frequencies; and d. warning indicator means responsive to said tone detector circuit means for producing said warning signal in response to said first level, said warning signal being readily perceivable by the driver of said vehicle.
Claim 3
Dependent Claim
40 words
The system of claim 1 wherein said tone detector means includes a plurality of phase locked loop tone decoder circuits, each responsive to audio frequency electrical signals in a separate predetermined frequency range, said predetermined frequency ranges being mutually exclusive.
Claim 4
Dependent Claim
17 words
The system of claim 1 wherein each of said frequency ranges is approximately 500 hertz in width.
Claim 5
Dependent Claim
23 words
The system of claim 3 wherein said frequency ranges lie within the range of frequencies from approximately 1000 hertz to approximately 3500 hertz.
Claim 6
Dependent Claim
45 words
The system of claim 1 wherein said sound transducer means includes a ceramic microphone oriented vertically downward toward said roadway, whereby said ceramic microphone is approximately equally responsive to reflected warning sound waves approaching said vehicle from any lateral direction with respect to said vehicle.
Claim 7
Dependent Claim
47 words
The system of claim 1 wherein said warning indicator means includes a warning light mounted in the driver's compartment of said vehicle, said warning light being lit when a warning sound having a frequency in one of said frequency ranges is received by said transducer sensing means.
Claim 8
Dependent Claim
30 words
The system of claim 1 wherein said warning indicator means includes an audio transducer for producing a characteristic audio frequency signal when said tone detecting means produces said first level.
Claim 9
Dependent Claim
16 words
The system of claim 7 wherein said audio amplifier means includes an integrated circuit audio amplifier.
Claim 10
Dependent Claim
16 words
The system of claim 2 wherein said phase locked loop tone decoder circuits are integrated circuits.
Claim 11
Dependent Claim
52 words
The system of claim 1 wherein said sound transducer means includes a microphone mounted at the top of a fender cavity of the vehicle, the microphone being oriented approximately downward to efficiently detect ones of said reflected warning sound signals entering said fender cavity from the bottom opening of said fender cavity.