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Patent US3210226A successfully refreshed from Google Patents.
US3210226A
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Method and means for controlling tapers in etching processes
Assignee: North American Aviation Corp
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Filing: 1961-09-28
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Granted: 1965-10-05
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Expires: 1981-09-28
Abstract
No abstract record available.
Inventors
- 👤 Jr Samuel Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:12
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/02; C23F1/10; C23F1/14; C23F1/16; C23F1/28
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
113 words
A METHOD OF CHEMICAL MILLING COMPRISING: MASKING A PORTION OF THE SURFACE OF A METAL WORKPIECE WITH AN ETCH RESISTANT MASK HAVING EDGES OF EXPOSING A PORTION OF SAID WORKPIECE; SUBJECTING THE EXPOSED PORTION OF SAID WORKPIECE TO LIQUID ETCHING MEDIUM FOR ETCHING THE EXPOSED PORTION TO FORM A DEPRESSION HAVING EDGE FILLETS; CONTROLLING THE ADVANCEMENT OF THE LIQUID ETCHING MEDIUM UNDER THE EDGES OF SAID MASK, BETWEEN SAID MASK AND T E UNETCHED WORKPIECE SURFACE AT A RATE RELATIVELY FASTER THAN THE RATE OF ADVANCEMENT OF ETCHING MEDIUM NORMAL TO THE SURFACE OF SAID WORKPIECE FOR FORMING THE EDGE FILLETS AS TAPERED PORTIONS BETWEEN THE DEPRESSION AND THE SURFACE OF SAID WORKPIECE.
Claim 2
Independent Claim
113 words
A METHOD OF CHEMICAL MILLING COMPRISING: MASKING A PORTION OF THE SURFACE OF A METAL WORKPIECE WITH AN ETCH RESISTANT MASK HAVING EDGES OF EXPOSING A PORTION OF SAID WORKPIECE; SUBJECTING THE EXPOSED PORTION OF SAID WORKPIECE TO LIQUID ETCHING MEDIUM FOR ETCHING THE EXPOSED PORTION TO FORM A DEPRESSION HAVING EDGE FILLETS; CONTROLLING THE ADVANCEMENT OF THE LIQUID ETCHING MEDIUM UNDER THE EDGES OF SAID MASK, BETWEEN SAID MASK AND T E UNETCHED WORKPIECE SURFACE AT A RATE RELATIVELY FASTER THAN THE RATE OF ADVANCEMENT OF ETCHING MEDIUM NORMAL TO THE SURFACE OF SAID WORKPIECE FOR FORMING THE EDGE FILLETS AS TAPERED PORTIONS BETWEEN THE DEPRESSION AND THE SURFACE OF SAID WORKPIECE.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-10-04 | 1969-04-05 | 1969-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-10-04 | 1973-04-05 | 1973-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-10-04 | 1977-04-05 | 1977-10-05 | $7700.00 | Window Closed / Lapsed |