Patent US3739376A successfully refreshed from Google Patents.
US3739376A
Expired / Lapsed
US
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Remote monitor and indicating system
Assignee: TRODYNE CORP
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Filing: 1970-10-12
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Granted: 1973-06-12
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Expires: 1990-10-12
Abstract
Abstract A passive parameter-sensing element is disposed at a location remote from an indicator. Upon the occurrence of a predetermined variation in the sensed parameter, an active unit coupled to the passive element produces a signal which operates the indicator. In one embodiment of the invention a plurality of passive sensing elements are housed in the blades of a helicopter. Upon the sensing of a change in the air pressure in one of the blades, the response of the passive element in that blade causes the active unit to produce a signal which has a characteristic uniquely associated with the particular blade in which the failure occurs.
Inventors
- 👤 F Keledy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:13
CPC Classifications
G; G08; G08C; G08C19/00; G08C19/12; B; B64; B64C; B64C27/00; B64C27/006; B64C27/007; G08B; G08B25/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
203 words
A system for monitoring a parameter at a plurality of spaced locations, said system comprising a plurality of parameter responsive switching means respectively located at said locations and operable in response to a predetermined change of said parameter, a plurality of electrically passive, normally inoperative resonant circuits respectively coupled to said parameter-sensitive means, said parameter sensitive switching means being effective when operated to render operative a corresponding one of said resonant circuits, a plurality of electrically active sources of signals at different frequencies located remote from said passive resonant circuits, a single winding coupled to the outputs of said plurality of signal sources and inductively coupled to said plurality of passive resonant circuits and effective upon the operation of one of said parameter-sensitive switching means to produce an electrical signal at one of said frequencies, said one of said frequencies being uniquely associated with said one of said parametersensitive means, a corresponding plurality of indicating means located remote from said passive resonant circuits, and a corresponding plurality of means having an input coupled to said single winding and an output respectively coupled to said indicating means for selectively applying said unique frequencies signal to a corresponding one of said plurality of indicating means.
Claim 2
Independent Claim
203 words
A system for monitoring a parameter at a plurality of spaced locations, said system comprising a plurality of parameter responsive switching means respectively located at said locations and operable in response to a predetermined change of said parameter, a plurality of electrically passive, normally inoperative resonant circuits respectively coupled to said parameter-sensitive means, said parameter sensitive switching means being effective when operated to render operative a corresponding one of said resonant circuits, a plurality of electrically active sources of signals at different frequencies located remote from said passive resonant circuits, a single winding coupled to the outputs of said plurality of signal sources and inductively coupled to said plurality of passive resonant circuits and effective upon the operation of one of said parameter-sensitive switching means to produce an electrical signal at one of said frequencies, said one of said frequencies being uniquely associated with said one of said parametersensitive means, a corresponding plurality of indicating means located remote from said passive resonant circuits, and a corresponding plurality of means having an input coupled to said single winding and an output respectively coupled to said indicating means for selectively applying said unique frequencies signal to a corresponding one of said plurality of indicating means.
Claim 3
Dependent Claim
22 words
The system of claim 1, in which said passive resonanT circuits each comprise an inductive winding inductively coupled to said single winding.
Claim 4
Dependent Claim
32 words
The system of claim 2, in which each of said signal sources includes a tuned circuit, said transformer winding being a component of the tuned circuit of each of said signal sources.
Claim 5
Dependent Claim
27 words
The system of claim 1, in which said signal applying means includes frequency-sensitive means respectively operatively interposed between said signal sources and said plurality of indicating means.
Claim 6
Dependent Claim
35 words
The system of claim 4, in which the outputs of each of said signal sources are coupled to a common point, and the inputs of said frequency-sensitive means are all coupled to said common point.
Claim 7
Dependent Claim
50 words
The system of claim 4, in which each of said indicating means comprises a first element operative only when the corresponding one of said parameter-sensitive means is in an operative condition, and a second element operative only when the corresponding one of said parameter-sensitive means is in its inoperative condition.
Claim 8
Dependent Claim
44 words
The system of claim 6, further comprising means operatively interposed between said signal producing means and said indicating means for selectively applying a control signal to one of said indicator elements in response to the condition of the associated one of said parameter-sensitive means.
Claim 9
Dependent Claim
125 words
In an aircraft having a plurality of blades rotatably mounted on a rotor, means on said aircraft for directing a beam of electromagnetic energy along a direction offset from the axis of the rotor so that when said blades are rotated said beam is sequentially and periodically interrupted by said blades, passive energy reflective means carried by said blades, switching means carried by said blades and operable in response to a change in the internal pressure of one of said blades for altering the reflective characteristics of the passive reflecting means on said one of said blades, and means located in the cockpit of said aircraft for sensing the change in the reflective characteristics of said passive reflective means, to thereby provide a warning indication.
Claim 10
Dependent Claim
125 words
In an aircraft having a plurality of blades rotatably mounted on a rotor, means on said aircraft for directing a beam of electromagnetic energy along a direction offset from the axis of the rotor so that when said blades are rotated said beam is sequentially and periodically interrupted by said blades, passive energy reflective means carried by said blades, switching means carried by said blades and operable in response to a change in the internal pressure of one of said blades for altering the reflective characteristics of the passive reflecting means on said one of said blades, and means located in the cockpit of said aircraft for sensing the change in the reflective characteristics of said passive reflective means, to thereby provide a warning indication.
Claim 11
Dependent Claim
65 words
The apparatus of claim 8, in which said passive reflective means each provide a different reflected signal to said sensing means, and further comprising means coupled to said sensing means for distinguishing the reflected signal, and a plurality of indicating means coupled to said signal-distinguishing means, one of said indicating means being made operative upon the operation of a corresponding one of said switch means.
Claim 12
Independent Claim
219 words
A system for detecting and indicating a predetermined change in a specified parameter at a plurality of remote locations comprising a plurality of electrically passive, normally inoperative resonant circuits resonant at a different frequency when operative and located respectively at said remote locations, a plurality of parameter-sensing switch means respectively coupled to said resonant circuits, said switch means being normally in a first inoperative state and being placed in a second operative state in response to said predetermined change in said parameter at one of said remote locations to render the one of said resonant circuits at said one remote location operative, a plurality of electrically active transmitting means producing signals at different frequencies and spaced from said remote locations and from said passive resonant circuits, said different frequencies being respectively approximately equal to the resonant frequencies of said resonant circuits, means for respectively inductively coupling said transmitting means to said passive resonant circuits, means coupled to said passive resonant circuits through said inductive coupling means for producing a fault signal upon the operation of said one of said passive resonant circuits, and indicating means coupled to said fault signal producing means and operable in response to said fault signal for providing an indication whenever said parameter changes by at least said predetermined amount at said one remote location.
Claim 13
Independent Claim
219 words
A system for detecting and indicating a predetermined change in a specified parameter at a plurality of remote locations comprising a plurality of electrically passive, normally inoperative resonant circuits resonant at a different frequency when operative and located respectively at said remote locations, a plurality of parameter-sensing switch means respectively coupled to said resonant circuits, said switch means being normally in a first inoperative state and being placed in a second operative state in response to said predetermined change in said parameter at one of said remote locations to render the one of said resonant circuits at said one remote location operative, a plurality of electrically active transmitting means producing signals at different frequencies and spaced from said remote locations and from said passive resonant circuits, said different frequencies being respectively approximately equal to the resonant frequencies of said resonant circuits, means for respectively inductively coupling said transmitting means to said passive resonant circuits, means coupled to said passive resonant circuits through said inductive coupling means for producing a fault signal upon the operation of said one of said passive resonant circuits, and indicating means coupled to said fault signal producing means and operable in response to said fault signal for providing an indication whenever said parameter changes by at least said predetermined amount at said one remote location.
Claim 14
Dependent Claim
36 words
The system of claim 10, in which said indicating means comprises a corresponding plurality of indicators, and further comprising a corresponding plurality of frequency-sensitive means respectively operatively interposed between said transmitters and said plurality of indicators.
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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) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |