US3071675A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Induction heater
Assignee: Dow Chemical Co
•
Filing: 1960-09-13
•
Granted: 1963-01-01
•
Expires: 1980-09-13
Abstract
No abstract record available.
Inventors
- 👤 Luther C Cronberger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:40
CPC Classifications
E; E21; E21B; E21B36/00; E21B36/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
96 words
A TUBING HEATER COMPRISING A HOLLOW TUBULAR SECTION MADE OF MAGNETIC MATERIAL, AT LEAST ONE ELECTRICAL PRIMARY COIL WINDING DISPOSED AROUND THE PERIPHERAL SURFACE OF SAID TUBULAR SECTION AND IN CLOSE SPACED RELATIONSHIP WITH RESPECT THERETO, AND AT LEAST ONE ARRARY OF GENERALLY C-SHAPED MAGNETIC RETURN ELEMENTS EACH HAVING A PAIR OF OPEN END ENDS, SAID MAGNETIC RETURN ELEMENTS BEING SYMMETRICALLY DISPOSED AROUND SAID TUBULAR SECTION WITH THEIR OPEN ENDS STRADDLING SAID PRIMARY COIL AND IN PHYSICAL CONTACT WITH SAID TUBULAR SECTION, SAID TUBULAR SECTION ALSO BEING THE SINGLE TURN SECONDARY WINDING OF THE TUBING HEATER.
Claim 2
Dependent Claim
96 words
A TUBING HEATER COMPRISING A HOLLOW TUBULAR SECTION MADE OF MAGNETIC MATERIAL, AT LEAST ONE ELECTRICAL PRIMARY COIL WINDING DISPOSED AROUND THE PERIPHERAL SURFACE OF SAID TUBULAR SECTION AND IN CLOSE SPACED RELATIONSHIP WITH RESPECT THERETO, AND AT LEAST ONE ARRARY OF GENERALLY C-SHAPED MAGNETIC RETURN ELEMENTS EACH HAVING A PAIR OF OPEN END ENDS, SAID MAGNETIC RETURN ELEMENTS BEING SYMMETRICALLY DISPOSED AROUND SAID TUBULAR SECTION WITH THEIR OPEN ENDS STRADDLING SAID PRIMARY COIL AND IN PHYSICAL CONTACT WITH SAID TUBULAR SECTION, SAID TUBULAR SECTION ALSO BEING THE SINGLE TURN SECONDARY WINDING OF THE TUBING HEATER.
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) | 1965-12-31 | 1966-07-02 | 1967-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-12-31 | 1970-07-02 | 1971-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-12-31 | 1974-07-02 | 1975-01-01 | $7700.00 | Window Closed / Lapsed |