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US3120838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Boiler for central heating systems and for preparing hot water
Assignee: Schiff and Stern GmbH
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Filing: 1961-02-24
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Granted: 1964-02-11
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Expires: 1981-02-24
Abstract
No abstract record available.
Inventors
- 👤 Mueller Walter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 13:44
CPC Classifications
F; F24; F24H; F24H1/00; F24H1/48; F24H1/52; F22; F22B; F22B7/00; F22B7/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
133 words
A BOILER STRUCTURE FOR A CENTRAL HEATING SYSTEM AND FOR PREPARING HOT WATER, A BOILER COMPRISING TWO OUTER SHEET CYLINDERS AND TWO INNER SHEET STEEL CYLINDERS TO DEFINE AN OUTER WATER JACKET AND AN INNER WATER JACKET, RESPECTIVELY, SAID INNER WATER JACKET BEING COAXIALLY DISPOSED IN SAID OUTER JACKET, A FIRST TUBE DEFINING A FIRST SMOKE FLUE EXTENDING AXIALLY THROUGH SAID INNER WATER JACKET, A SECOND TUBE DEFINING A SECOND SMOKE FLUE EXTENDING AXIALLY THROUGH SAID OUTER WATER JACKET, MEANS DURING THIRD AND FOURTH SMOKE FLUES EXTENDING AXIALLY BETWEEN SAID INNER AND OUTER WATER JACKETS, MEANS FEEDING COLD WATER INTO SAID INNER WATER JACKET, HOT WATER DISCHARGE MEANS CONNECTED WITH SAID INNER WATER JACKET, MEANS FEEDING COLD WATER INTO SAID OUTER WATER JACKET, HOT WATER DISCHARGE MEANS CONNECTED WITH SAID OUTER WATER JACKET,
Claim 2
Dependent Claim
133 words
A BOILER STRUCTURE FOR A CENTRAL HEATING SYSTEM AND FOR PREPARING HOT WATER, A BOILER COMPRISING TWO OUTER SHEET CYLINDERS AND TWO INNER SHEET STEEL CYLINDERS TO DEFINE AN OUTER WATER JACKET AND AN INNER WATER JACKET, RESPECTIVELY, SAID INNER WATER JACKET BEING COAXIALLY DISPOSED IN SAID OUTER JACKET, A FIRST TUBE DEFINING A FIRST SMOKE FLUE EXTENDING AXIALLY THROUGH SAID INNER WATER JACKET, A SECOND TUBE DEFINING A SECOND SMOKE FLUE EXTENDING AXIALLY THROUGH SAID OUTER WATER JACKET, MEANS DURING THIRD AND FOURTH SMOKE FLUES EXTENDING AXIALLY BETWEEN SAID INNER AND OUTER WATER JACKETS, MEANS FEEDING COLD WATER INTO SAID INNER WATER JACKET, HOT WATER DISCHARGE MEANS CONNECTED WITH SAID INNER WATER JACKET, MEANS FEEDING COLD WATER INTO SAID OUTER WATER JACKET, HOT WATER DISCHARGE MEANS CONNECTED WITH SAID OUTER WATER JACKET,
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) | 1967-02-10 | 1967-08-12 | 1968-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-02-10 | 1971-08-12 | 1972-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-02-10 | 1975-08-12 | 1976-02-11 | $7700.00 | Window Closed / Lapsed |