US3585261A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Producing hot pressed ferrites utilizing thoria as a parting compound
Assignee: Ampex Corp
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Filing: 1968-09-12
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Granted: 1971-06-15
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Expires: 1988-09-12
Abstract
Abstract IN THE PRIOR ART HOT PRESSED FERRITE ARETICLES HAVE BEEN MADE BY COLD PRESSING FINELY GROUNDFERRITE COMPOSITIONS, SINTERING THE COLD PRESSED FERRITE SHAPE, SURROUNDING THE COOLED SINTERED SHAPE WITH FINELY GROUND ZIRCONIA OR ALUMINA PARTING AGENT IN A HOT PRESS CAVITY AND HOT PRESSING THE SINTERED FERRITE SHAPE TO FINAL DENSITY. THE PRESENT INVENTION USES THORIA IN PLACE OF THE ZIRCONIA OR ALUMINA PARTING AGENT WHICH ELIMINATES ANY REACTION BETWEEN THE PARTING AGENT AND THE FERRITE THAT WOULD AFFECT THE MAGNETIC PROPERTIES OF THE FERRITE.
Inventors
- 👤 Paul D Baba
- 👤 Joel E Zneimer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:20
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/26
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-14 | 1974-12-14 | 1975-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-14 | 1978-12-14 | 1979-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-14 | 1982-12-14 | 1983-06-15 | $7700.00 | Window Closed / Lapsed |