← Back to Patent Explorer
US2890944A Expired / Lapsed US ⏱️ 0.0 years remaining

Continuous chemical milling process

Assignee: North American Aviation Corp
•
Filing: 1956-05-25
•
Granted: 1959-06-16
•
Expires: 1976-05-25
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

No abstract record available.

Inventors

  • 👤 Stephen A Hays

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 09:23
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)

US2235658A Cited
US2337062A Cited
US2662814A Cited

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

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag