Patent US2890944A successfully refreshed from Google Patents.
US2890944A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Continuous chemical milling process
Assignee: North American Aviation Corp
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Filing: 1956-05-25
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Granted: 1959-06-16
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Expires: 1976-05-25
Abstract
No abstract record available.
Inventors
- 👤 Stephen A Hays
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 04:41
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/28
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
131 words
THE CONTINUOUS PROCESS OF CHEMICALLY MILLING WORKPIECES OF GROUP VIII METALS AND ALLOYS THEREOF COMPRISING EXPOSING A WORKPIECE TO THE ETCHING ACTION OF A BATH INITIALLY CONTAINING DISSOLVED PHOSPHORUS AND METAL IN A PREDETERMINED WEIGHT RATIO OF FROM ABOUT 0.23 TO ABOUT 1.50 PHOSPHORUS-TO-METAL, WHEREIN THE PHOSPHORUS IS PRESENT IN THE FORM OF SOLUBLE PHOSPHATS, WITHDRAWING PARTIALLY SPENT PORTIONS OF SAID BATH CONTINIG SAID DISSOLVED METAL AND PHOSPHORUS, PRECIPITATING METAL PHOSPHATES FROM SAID PORTIONS TO FORM A PRECIPTATE OF METAL PHOSPHATE AND AN EFFUENT CONTAINING METAL HYDROGEN PHOSPHATES, RETURNING SAID EFFUENT TO SAID BATH, AND ADDING PHOSPHORUS IN THE FORM OF PHOSPHATES TO SAID BATH IN AN AMOUNT SUBSTANTIALLY EQUIVALENT TO THE PHOSPHORUS REMOVED IN SAID PARTIALLY SPENT PORTIONS AND MAINTAINING SAID DISSOLVED METAL AND PHOSPHORUS AT SAID PREDETERMINED WEIGHT RATIO.
Claim 2
Dependent Claim
131 words
THE CONTINUOUS PROCESS OF CHEMICALLY MILLING WORKPIECES OF GROUP VIII METALS AND ALLOYS THEREOF COMPRISING EXPOSING A WORKPIECE TO THE ETCHING ACTION OF A BATH INITIALLY CONTAINING DISSOLVED PHOSPHORUS AND METAL IN A PREDETERMINED WEIGHT RATIO OF FROM ABOUT 0.23 TO ABOUT 1.50 PHOSPHORUS-TO-METAL, WHEREIN THE PHOSPHORUS IS PRESENT IN THE FORM OF SOLUBLE PHOSPHATS, WITHDRAWING PARTIALLY SPENT PORTIONS OF SAID BATH CONTINIG SAID DISSOLVED METAL AND PHOSPHORUS, PRECIPITATING METAL PHOSPHATES FROM SAID PORTIONS TO FORM A PRECIPTATE OF METAL PHOSPHATE AND AN EFFUENT CONTAINING METAL HYDROGEN PHOSPHATES, RETURNING SAID EFFUENT TO SAID BATH, AND ADDING PHOSPHORUS IN THE FORM OF PHOSPHATES TO SAID BATH IN AN AMOUNT SUBSTANTIALLY EQUIVALENT TO THE PHOSPHORUS REMOVED IN SAID PARTIALLY SPENT PORTIONS AND MAINTAINING SAID DISSOLVED METAL AND PHOSPHORUS AT SAID PREDETERMINED WEIGHT RATIO.
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) | 1962-06-15 | 1962-12-15 | 1963-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-06-15 | 1966-12-15 | 1967-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-06-15 | 1970-12-15 | 1971-06-16 | $7700.00 | Window Closed / Lapsed |