Patent US3127571A successfully refreshed from Google Patents.
US3127571A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for producing frequency changes by oppositely varying two inductors
Assignee: Imperial Chemical Industries Ltd
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Filing: 1959-05-25
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Granted: 1964-03-31
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Expires: 1979-05-25
Abstract
No abstract record available.
Inventors
- 👤 Croweroft Peter Lester
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:39
CPC Classifications
G; G01; G01L; G01L9/00; G01L9/0001; G01L9/0004; G01L9/10; G01L9/105
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
167 words
APPARATUS FOR SENSING A PHYSICAL DISPLACEMENT AND PRODUCING AN ELECTRICAL SIGNAL THE FREQUENCY OF WHICH BEARS A LINEAR RELATION TO THE SAID DISPLACEMENT, COMPRISING IN COMBINATION A PAIR OF INDUCTANCE TRANSDUCERS, EACH TRANSDUCER INCLUDING COIL MEANS AND A MAGNETIC CIRCUIT LINKING SAID COIL MEANS AND HAVING AN AIR GAP THEREIN; SENSING MEANS OPERATIVELY CONNECTED TO SAID PAIR OF TRANSDUCERS AND RESPONSIVE TO AN APPLIED DISPLACEMENT TO ADJUST THE AIR GAPS OF EACH MAGNETIC CIRCUIT IN OPPOSITE SENSES TO AN EXTENT PROPORTIONATE TO THE DISPLACEMENT TO PRODUCE AN INDUCTANCE CHANGE IN ONE OF SAID TRANSDUCERS WHICH IS INVERSELY PROPORTIONAL TO A DECREASE IN THE AIR GAP OF ITS ASSOCIATED MAGNETIC CIRCUIT RESULTING FROM THE ADJUSTMENT AND TO PRODUCE AN INDUCTANCE CHANGE IN THE OTHER OF SAID TRANSDUCERS WHICH IS INVERSELY PROPORTIONAL TO AN INCREASE IN THE AIR GAP OF ITS ASSOCIATED MAGNETIC CIRCUIT RESULTING FROM THE ADJUSTMENT; A CIRCUIT CONNECTED TO EACH COIL MEANS TO FORM THEREWITH SEPARATE OSCILLATORS THE FREQUENCIES OF WHICH ARE MODULATED IN INVERSE PRO-
Claim 2
Dependent Claim
167 words
APPARATUS FOR SENSING A PHYSICAL DISPLACEMENT AND PRODUCING AN ELECTRICAL SIGNAL THE FREQUENCY OF WHICH BEARS A LINEAR RELATION TO THE SAID DISPLACEMENT, COMPRISING IN COMBINATION A PAIR OF INDUCTANCE TRANSDUCERS, EACH TRANSDUCER INCLUDING COIL MEANS AND A MAGNETIC CIRCUIT LINKING SAID COIL MEANS AND HAVING AN AIR GAP THEREIN; SENSING MEANS OPERATIVELY CONNECTED TO SAID PAIR OF TRANSDUCERS AND RESPONSIVE TO AN APPLIED DISPLACEMENT TO ADJUST THE AIR GAPS OF EACH MAGNETIC CIRCUIT IN OPPOSITE SENSES TO AN EXTENT PROPORTIONATE TO THE DISPLACEMENT TO PRODUCE AN INDUCTANCE CHANGE IN ONE OF SAID TRANSDUCERS WHICH IS INVERSELY PROPORTIONAL TO A DECREASE IN THE AIR GAP OF ITS ASSOCIATED MAGNETIC CIRCUIT RESULTING FROM THE ADJUSTMENT AND TO PRODUCE AN INDUCTANCE CHANGE IN THE OTHER OF SAID TRANSDUCERS WHICH IS INVERSELY PROPORTIONAL TO AN INCREASE IN THE AIR GAP OF ITS ASSOCIATED MAGNETIC CIRCUIT RESULTING FROM THE ADJUSTMENT; A CIRCUIT CONNECTED TO EACH COIL MEANS TO FORM THEREWITH SEPARATE OSCILLATORS THE FREQUENCIES OF WHICH ARE MODULATED IN INVERSE PRO-
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) | 1967-03-31 | 1967-09-30 | 1968-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-03-31 | 1971-09-30 | 1972-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-03-31 | 1975-09-30 | 1976-03-31 | $7700.00 | Window Closed / Lapsed |