US2590894A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical conductor
Assignee: Individual
•
Filing: 1949-09-20
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Granted: 1952-04-01
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Expires: 1969-09-20
Abstract
No abstract record available.
Inventors
- 👤 Paul H Sanborn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:52
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; H; H01; H01C; H01C7/00; H01C7/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
164 words
AN ELECTRICALLY CONDUCTING CERAMIC BODY HAVING A NEGATIVE TEMPERATURE COEFFICIENT OF RESISTANCE, SAID BODY BEING A FIRED SUBSTANTIALLY HOMOGENEOUS VITRIFIED COMPOSITION CONSISTING OF FROM 0.05 TO 63% TITANIUM DIOXIDE, 23.88 TO 99.95% FERRIC OXIDE AND 0 TO 75% OTHER CERAMIC OXIDES BY WEIGHT, SAID OTHER CERAMIC OXIDES BEING IN A STATE OF OXIDATION EQUIVALENT TO THAT OF FERRIC OXIDE AND TITANIUM DIOXIDE, THE PERCENTAGE OF ANY HEAVY METAL OXIDES OTHER THAN SAID FERRIC OXIDE AND SAID TITANIUM DIOXIDE NOT EXCEEDING THE PERCENTAGE OF SAID TITANIUM DOIXIDE, AND IN ANY SAID COMPOSITION THE PERCENTAGE OF TITANIUM DIOXIDE NOT BEING GREATER THAN THAT OBTAINED BY MULTIPLYING THE PERCENTAGE OF FERRIC OXIDE BY 4.7165 AND THEN SUBSTRACTING 111.51%. OR LESS THAN THAT OBTAINED BY MULTIPLYING THE PERCENTAGE OF FERRIC OXIDE BY 0.01407 AND SUBTRACTING THE RESULT FROM 1.4560% AND THE PERCENTAGE OF OTHER CERAMIC OXIDES NOT BEING GREATER THAN THAT OBTAINED BY MULTIPLYING THE PERCENTAGE OF FERRIC OXIDE BY 0.9859 AND SUBTRACTING THE LATTER RESULT FROM 98.544%.
Claim 2
Dependent Claim
164 words
AN ELECTRICALLY CONDUCTING CERAMIC BODY HAVING A NEGATIVE TEMPERATURE COEFFICIENT OF RESISTANCE, SAID BODY BEING A FIRED SUBSTANTIALLY HOMOGENEOUS VITRIFIED COMPOSITION CONSISTING OF FROM 0.05 TO 63% TITANIUM DIOXIDE, 23.88 TO 99.95% FERRIC OXIDE AND 0 TO 75% OTHER CERAMIC OXIDES BY WEIGHT, SAID OTHER CERAMIC OXIDES BEING IN A STATE OF OXIDATION EQUIVALENT TO THAT OF FERRIC OXIDE AND TITANIUM DIOXIDE, THE PERCENTAGE OF ANY HEAVY METAL OXIDES OTHER THAN SAID FERRIC OXIDE AND SAID TITANIUM DIOXIDE NOT EXCEEDING THE PERCENTAGE OF SAID TITANIUM DOIXIDE, AND IN ANY SAID COMPOSITION THE PERCENTAGE OF TITANIUM DIOXIDE NOT BEING GREATER THAN THAT OBTAINED BY MULTIPLYING THE PERCENTAGE OF FERRIC OXIDE BY 4.7165 AND THEN SUBSTRACTING 111.51%. OR LESS THAN THAT OBTAINED BY MULTIPLYING THE PERCENTAGE OF FERRIC OXIDE BY 0.01407 AND SUBTRACTING THE RESULT FROM 1.4560% AND THE PERCENTAGE OF OTHER CERAMIC OXIDES NOT BEING GREATER THAN THAT OBTAINED BY MULTIPLYING THE PERCENTAGE OF FERRIC OXIDE BY 0.9859 AND SUBTRACTING THE LATTER RESULT FROM 98.544%.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-04-01 | 1955-10-01 | 1956-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-04-01 | 1959-10-01 | 1960-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-04-01 | 1963-10-01 | 1964-04-01 | $7700.00 | Window Closed / Lapsed |