← Back to Patent Explorer
US2777258A Expired / Lapsed US ⏱️ 0.0 years remaining

Sharpening machine

Assignee: DARELL E AVRA
•
Filing: 1953-09-01
•
Granted: 1957-01-15
•
Expires: 1973-09-01
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

No abstract record available.

Inventors

  • 👤 Lela M Avra

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 14:24
CPC Classifications
B; B24; B24B; B24B3/00; B24B3/36; B24B3/42

Claims Analysis

Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.

References Cited (Backward Citations)

US556868A Cited
US1967118A Cited
US2149774A Cited
US2187289A Cited
US2286970A Cited
US2279798A Cited
US2377126A Cited
US2466905A Cited
US2493619A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1960-01-15 1960-07-16 1961-01-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1964-01-15 1964-07-16 1965-01-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1968-01-15 1968-07-16 1969-01-15 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag