US3218180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat exchange body
Assignee: Individual
•
Filing: 1961-07-28
•
Granted: 1965-11-16
•
Expires: 1981-07-28
Abstract
No abstract record available.
Inventors
- 👤 Erik C Sjostrand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:23
CPC Classifications
C; C04; C04B; C04B33/00; C04B33/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
45 words
A SOLID SHAPED BODY SUITABLE FOR USE AS A HEAT EXCHANGE MEANS AND CHARACTERIZED BY HIGH RESISTANCE TO MECHANICAL AND THERMAL STRESS AND CONSISTING ESSENTIALLY OF A FIRED ADMIXTURE OF PARTICULATE OIL SHALE ASH AND FROM ABOUT 0.2 TO ABOUT 10% BY WEIGHT OF BENTONITE.
Claim 2
Dependent Claim
45 words
A SOLID SHAPED BODY SUITABLE FOR USE AS A HEAT EXCHANGE MEANS AND CHARACTERIZED BY HIGH RESISTANCE TO MECHANICAL AND THERMAL STRESS AND CONSISTING ESSENTIALLY OF A FIRED ADMIXTURE OF PARTICULATE OIL SHALE ASH AND FROM ABOUT 0.2 TO ABOUT 10% BY WEIGHT OF BENTONITE.
References Cited (Backward Citations)
US2880100A
Cited
US2965504A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-11-15 | 1969-05-17 | 1969-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-15 | 1973-05-17 | 1973-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-15 | 1977-05-17 | 1977-11-16 | $7700.00 | Window Closed / Lapsed |