Patent US3111571A successfully refreshed from Google Patents.
US3111571A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric heating unit
Assignee: WILLIAMSON Co
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Filing: 1962-01-26
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Granted: 1963-11-19
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Expires: 1982-01-26
Abstract
No abstract record available.
Inventors
- 👤 Camp Albert E De
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:53
CPC Classifications
F; F24; F24H; F24H3/00; F24H3/02; F24H3/04; F24H3/0405; F24D; F24D5/00; F24D5/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
101 words
A LOW VOLTAGE CONTROLLED ELECTRIC HEATING UNIT ADAPTED TO BE UTILIZED IN A FORCED AIR SYSTEM COMPRISING, A SECTION OF DUCT IN THE FORM OF AN OUTER SLEEVE, AN INNER SLEEVE MOUNTED WITHIN SAID OUTER SLEEVE, LONGITUDINALLY EXTENDING CHANNEL MEANS BETWEEN SAID SLEEVES HAVING LATERAL EDGES DEFINED BY A PAIR OF LONGITUDINALLY EXTENDING MEMBERS, AN ELECTRIC HEATING ELEMENT WOUND IN AN AXIALLY REVERSING MANNER MOUNTED AROUND THE INNER SURFACE OF SAID INNER SLEEVE, SAID ELEMENT HAVING REVERSE CURVES OCCURRING AT POINTS ADJACENT SAID LONGITUDINALLY EXTENDING MEMBERS, A TERMINAL BOX MOUNTED UPON SAID HEATING UNIT OVER SAID CHANNEL MEANS WHEREBY AIR PASS-
Claim 2
Dependent Claim
101 words
A LOW VOLTAGE CONTROLLED ELECTRIC HEATING UNIT ADAPTED TO BE UTILIZED IN A FORCED AIR SYSTEM COMPRISING, A SECTION OF DUCT IN THE FORM OF AN OUTER SLEEVE, AN INNER SLEEVE MOUNTED WITHIN SAID OUTER SLEEVE, LONGITUDINALLY EXTENDING CHANNEL MEANS BETWEEN SAID SLEEVES HAVING LATERAL EDGES DEFINED BY A PAIR OF LONGITUDINALLY EXTENDING MEMBERS, AN ELECTRIC HEATING ELEMENT WOUND IN AN AXIALLY REVERSING MANNER MOUNTED AROUND THE INNER SURFACE OF SAID INNER SLEEVE, SAID ELEMENT HAVING REVERSE CURVES OCCURRING AT POINTS ADJACENT SAID LONGITUDINALLY EXTENDING MEMBERS, A TERMINAL BOX MOUNTED UPON SAID HEATING UNIT OVER SAID CHANNEL MEANS WHEREBY AIR PASS-
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) | 1966-11-18 | 1967-05-20 | 1967-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-11-18 | 1971-05-20 | 1971-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-11-18 | 1975-05-20 | 1975-11-19 | $7700.00 | Window Closed / Lapsed |