Patent US3206329A successfully refreshed from Google Patents.
US3206329A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Insulation coating for indirectly heated cathode heaters
Assignee: General Electric Co
•
Filing: 1962-01-08
•
Granted: 1965-09-14
•
Expires: 1982-01-08
Abstract
No abstract record available.
Inventors
- 👤 James C Hickle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:32
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/13; H01J1/20; H01J1/22
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
90 words
IN THE FABRICATION OF INDIRECTLY-HEATED CATHODES FOR ELECTRON DISCHARGE DEVICES TO MINIMIZE UNDESIRED RISE OF HEATER CURRENT AND HEATER-CATHODE ELECTRICAL CONDUCTIVITY, AND TO AVOID FRACTURE OF HEATER WIRE DURING NORMAL OPERATION OF SAID DEVICES, THE METHOD WHICH COMPRISES THE STEPS OF LEACHING A QUANTITY OF MULLITE POWDER TO REMOVE OXIDES OF MAGNESIUM AND IRON THAT MAY BE PRESENT AS IMPURITIES, FORMING A SLURRY HAVING NOT MORE THAN 90%, BY WEIGHT, ALUMINA IN A PRESELECTED VEHICLE, AND APPLYING THE LEACHED MULLITE AND ALUMINA TO A WIRE TO FORM A COATNG THEREON.
Claim 2
Dependent Claim
90 words
IN THE FABRICATION OF INDIRECTLY-HEATED CATHODES FOR ELECTRON DISCHARGE DEVICES TO MINIMIZE UNDESIRED RISE OF HEATER CURRENT AND HEATER-CATHODE ELECTRICAL CONDUCTIVITY, AND TO AVOID FRACTURE OF HEATER WIRE DURING NORMAL OPERATION OF SAID DEVICES, THE METHOD WHICH COMPRISES THE STEPS OF LEACHING A QUANTITY OF MULLITE POWDER TO REMOVE OXIDES OF MAGNESIUM AND IRON THAT MAY BE PRESENT AS IMPURITIES, FORMING A SLURRY HAVING NOT MORE THAN 90%, BY WEIGHT, ALUMINA IN A PRESELECTED VEHICLE, AND APPLYING THE LEACHED MULLITE AND ALUMINA TO A WIRE TO FORM A COATNG THEREON.
Claim 3
Dependent Claim
34 words
THE METHOD AS DEFINED IN CLAIM 1, WHEREIN SAID SLURRY COMPRISES 100%, BY WEIGHT, MULLITE AND FURTHER COMPRISING AN ADDITIONAL STEP OF APPLYING A LAYER OF SUBSTANTIALLY PURE ALUMINA OVER THE LAYER OF MULLITE.
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) | 1968-09-13 | 1969-03-15 | 1969-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-09-13 | 1973-03-15 | 1973-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-09-13 | 1977-03-15 | 1977-09-14 | $7700.00 | Window Closed / Lapsed |