← Back to Patent Explorer
US2561357A Expired / Lapsed US ⏱️ 0.0 years remaining

Frequency monitoring and indicating system

Assignee: International Standard Electric Corp
•
Filing: 1947-12-24
•
Granted: 1951-07-24
•
Expires: 1967-12-24
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

No abstract record available.

Inventors

  • 👤 Garfield William Littery

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 10:12
CPC Classifications
G; G05; G05B; G05B1/00; G05B1/01; G05B1/02; G05B1/022

Claims Analysis

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

References Cited (Backward Citations)

US1647270A Cited
US1781497A Cited
US1977776A Cited
US2112826A Cited
US2421771A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1954-07-23 1955-01-22 1955-07-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1958-07-23 1959-01-22 1959-07-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1962-07-23 1963-01-22 1963-07-24 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag