US3889185A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lightning current measuring systems
Assignee: National Aeronautics and Space Administration
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Filing: 1974-04-15
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Granted: 1975-06-10
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Expires: 1994-04-15
Abstract
Abstract An apparatus for monitoring and analyzing electrical currents produced by lightning strikes. The apparatus includes an electrical conductive mast having a first circuit coupled thereto for generating a DC voltage proportional to a peak current generated in the mast by each lightning strike. A second circuit is coupled to the mast for generating a digital signal representative of the wave shape of the current generated in the mast by each lightning strike and a third circuit is provided closely adjacent the mast for producing a reference voltage. Signals are fed into a strip chart recorder making a permanent record of the current produced by the lightning strike.
Inventors
- 👤 Ronald J Wojtasinski
- 👤 James H Jones
- 👤 Raymond V Lisle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:58
CPC Classifications
G; G01; G01R; G01R15/00; G01R15/14; G01R15/18; G01R15/181
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
299 words
An apparatus for monitoring and analyzing electrical currents produced by lightning strikes comprising: a. an electrically conductive mast having currents produced therein responsive to lightning strikes, b. a first circuit means coupled to said mast for generating a voltage proportional to a peak current generated in said mast by each lightning strike, c. said first circuit means including: i. a first coil encircling said mast for sensing the flux change produced by said current flowing through said mast and generating a voltage responsive thereto, ii. an integrator coupled to said first coil for generating an integrated voltage proportional to said flux change sensed by said first coil, iii. a peak voltage detector coupled to said integrator for generating a voltage having an amplitude proportional to the peak of said integrated voltage, d. a second circuit means coupled to said mast for generating a digital signal representative of the wave shape of said current generated in said mast by each lightning strike, e. said second circuit means including: i. a second coil encircling said mast for sensing the flux change produced by said current flowing through said mast caused by a lightning strike and generating a voltage responsive thereto, ii. a second integrator coupled to said second coil for generating an integrated voltage directly proportional to the amplitude of said current flowing in said lightning mast, iii. an analog to digital convertor coupled to said second integrator for sampling said integrated voltage at a predetermined rate and generating digital signals corresponding to said integrated voltage, and f. means for recording said voltage generated by said first circuit and said digital signals produced by said second circuit for producing a record representing the wave shape of said current produced in said mast by said lightning strike and the peak current produced.
Claim 2
Independent Claim
299 words
An apparatus for monitoring and analyzing electrical currents produced by lightning strikes comprising: a. an electrically conductive mast having currents produced therein responsive to lightning strikes, b. a first circuit means coupled to said mast for generating a voltage proportional to a peak current generated in said mast by each lightning strike, c. said first circuit means including: i. a first coil encircling said mast for sensing the flux change produced by said current flowing through said mast and generating a voltage responsive thereto, ii. an integrator coupled to said first coil for generating an integrated voltage proportional to said flux change sensed by said first coil, iii. a peak voltage detector coupled to said integrator for generating a voltage having an amplitude proportional to the peak of said integrated voltage, d. a second circuit means coupled to said mast for generating a digital signal representative of the wave shape of said current generated in said mast by each lightning strike, e. said second circuit means including: i. a second coil encircling said mast for sensing the flux change produced by said current flowing through said mast caused by a lightning strike and generating a voltage responsive thereto, ii. a second integrator coupled to said second coil for generating an integrated voltage directly proportional to the amplitude of said current flowing in said lightning mast, iii. an analog to digital convertor coupled to said second integrator for sampling said integrated voltage at a predetermined rate and generating digital signals corresponding to said integrated voltage, and f. means for recording said voltage generated by said first circuit and said digital signals produced by said second circuit for producing a record representing the wave shape of said current produced in said mast by said lightning strike and the peak current produced.
Claim 3
Dependent Claim
86 words
The apparatus as set forth in claim 2 wherein said second circuit incLudes: a. a magnetic core provided for generating a triggering signal responsive to said second coil sensing a flux change in said mast for triggering said analog-to-digital convertor off after a predetermined period of time, b. a digital memory coupled to an output of said analog to digital convertor for storing said digital signal from said analog to digital convertor, and c. said means for recording includes a strip recorder for recording said signals.
Claim 4
Dependent Claim
93 words
The apparatus as set forth in claim 1 further comprising: a. shielded cables connecting said first and second coils to said first and second integrators respectively, b. a reference voltage circuit, c. said reference voltage circuit including: i. a third coil carried closely adjacent said mast, ii. a third integrator, iii. a shielded cable connecting said third coil to said third integrator, and iv. a peak voltage detector coupled to said third integrator for generating a reference voltage corresponding to the induced voltage generated in said shielded cable responsive to a lightning strike.
Claim 5
Dependent Claim
31 words
The apparatus as set forth in claim 1 further comprising: a. an auxiliary self sustaining power supply coupled to said integrators, peak voltage detectors, analog-to-digital convertor and said means for recording.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-09 | 1978-12-09 | 1979-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-09 | 1982-12-09 | 1983-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-09 | 1986-12-09 | 1987-06-10 | $7700.00 | Window Closed / Lapsed |