← Back to Patent Explorer
US2558637A Expired / Lapsed US ⏱️ 0.0 years remaining

Flash-back indicator

Assignee: WALKIRT Co
•
Filing: 1949-04-12
•
Granted: 1951-06-26
•
Expires: 1969-04-12
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

No abstract record available.

Inventors

  • 👤 Richard F Walz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 09:14
CPC Classifications
H; H02; H02H; H02H7/00; H02H7/10; H02H7/12; H02H7/125; H02H7/127

Claims Analysis

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

References Cited (Backward Citations)

US2057531A Cited
US2141927A Cited
US2405397A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1954-06-25 1954-12-25 1955-06-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1958-06-25 1958-12-25 1959-06-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1962-06-25 1962-12-25 1963-06-26 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag