← Back to Patent Explorer
US3158805A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for magnetically marking sheet steel by deposition of metal ions

Assignee: Individual
•
Filing: 1958-06-02
•
Granted: 1964-11-24
•
Expires: 1978-06-02
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

No abstract record available.

Inventors

  • 👤 David C Kalbfell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 03:09
CPC Classifications
H; H01; H01F; H01F41/00; H01F41/14; H01F41/18

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 68 words
IN COMBINATION: FIRST AND SECOND MAGNETIZABLE METALLIC MEANS HAVING FIRST AND SECOND PERMEABILITY VALUES, RESPECTIVELY; MEANS FOR ALLOYING A PORTION OF SAID FIRST MAGNETIZABLE MEANS WITH SAID SECOND MAGNETIZABLE MEANS AT A PREDETERMINED SURFACE PART WHEREBY SAID PREDETERMINED PART HAS A PERMEABILITY VALUE DIFFERING FROM SAID FIRST PERMEABILITY VALUE OF THE REMAINING SURFACE PART; AND PERMEABILITY DIFFERENCE DETECTING MEANS RESPECTIVELY ASSOCIATED WITH SAID REMAINING SURFACE PART OF THE

References Cited (Backward Citations)

US2477099A Cited
US1139291A Cited
US2239642A Cited
US2466251A Cited
US2612582A Cited
US2703384A Cited
US2814719A Cited
US2885534A Cited
US2832040A Cited
US2844788A Cited
US2845524A Cited
US2922023A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1967-11-24 1968-05-25 1968-11-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1971-11-24 1972-05-25 1972-11-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1975-11-24 1976-05-25 1976-11-24 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag