US4100529A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Road hazard warning system, indicating specific hazard
Assignee: MEWS Inc
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Filing: 1976-09-13
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Granted: 1978-07-11
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Expires: 1996-09-13
Abstract
Abstract System for warning vehicle drivers of the proximity of a road hazard. Each road hazard, moving emergency vehicles for example, have associated with them a radio frequency signal transmitter which transmits a pulse length coded signal which is unique for each hazard. Private vehicles have receivers which are responsive to the set radio frequency. When such a vehicle is within range of the road hazard warning transmitter, a light in the vehicle will flash on and off in synchronism with the pulse length coded signal. In addition, this signal drives a sound generator on and off in synchronism with the flashing light producing a coded audio signal. The Radio frequency pulse length coded signal is modulated at an audio frequency in the receiver without disturbing the pulse length code of the radio frequency signal. This then allows a human observer to hear the pulse length code as a coded audio signal.
Inventors
- 👤 Edgar J. Evans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:29
CPC Classifications
G; G08; G08G; G08G1/00; G08G1/09; G08G1/0962; G08G1/0967; G08G1/096708; G08G1/096716; G08G1/096733; G08G1/096758; G08G1/096766; G08G1/096791
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
187 words
In a warning system to enable drivers of vehicles to be alerted to the presence of road hazards, the combination which comprises: transmitter means associated with said road hazards for transmitting a pulse length coded radio frequency signal that is unique for each particular road hazard; receiver means carried by said vehicles for receiving said pulse length coded signal; audio frequency generator means, comprising an audio frequency circuit connected in a feedback loop of a transistor amplifier, connected with said receiver means for further modulating said pulse length coded signal at an audio frequency, the period of oscillation of said audio frequency circuit serving to modulate said pulse length coded signal without disturbing said pulse length code; a visible light emitting means connected to the output of said audio frequency generator means for flashing in synchronism with said pulse length code signal from said transmitter; and an audible sound emitting means connected in series with said visible light emitting means for sounding an audible warning at the frequency set by said audio frequency generator means and in synchronism with said pulse length code from said transmitter means.
Claim 2
Dependent Claim
187 words
In a warning system to enable drivers of vehicles to be alerted to the presence of road hazards, the combination which comprises: transmitter means associated with said road hazards for transmitting a pulse length coded radio frequency signal that is unique for each particular road hazard; receiver means carried by said vehicles for receiving said pulse length coded signal; audio frequency generator means, comprising an audio frequency circuit connected in a feedback loop of a transistor amplifier, connected with said receiver means for further modulating said pulse length coded signal at an audio frequency, the period of oscillation of said audio frequency circuit serving to modulate said pulse length coded signal without disturbing said pulse length code; a visible light emitting means connected to the output of said audio frequency generator means for flashing in synchronism with said pulse length code signal from said transmitter; and an audible sound emitting means connected in series with said visible light emitting means for sounding an audible warning at the frequency set by said audio frequency generator means and in synchronism with said pulse length code from said transmitter means.
Claim 3
Dependent Claim
106 words
The system of claim 1 wherein said audio frequency generator means includes: a transistor having a base connected to said receiver means for receiving said pulse length coded signal, a collector connected to a power supply, and an emitter, said visible light emitting means and said audible sound emitting means being connected in series between said collector and said emitter; and an audio frequency circuit connected in a feedback loop between the emitter and the base of said transistor, the period of oscillation of said audio frequency circuit serving to modulate said pulse length code at an audio frequency without disturbing the continuity of said code.
Claim 4
Dependent Claim
62 words
The system of claim 1 which further includes: variable resistance means connected in parallel with said audible sound emitting means, said variable resistance means being variable to allow more or less of the power of said audio frequency pulse length coded signal to pass through said audible sound emitting means to thereby vary the output volume of said audible sound emitting means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-07-10 | 1982-01-09 | 1982-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-10 | 1986-01-09 | 1986-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-10 | 1990-01-09 | 1990-07-11 | $7700.00 | Window Closed / Lapsed |