Patent US3551033A successfully refreshed from Google Patents.
← Back to Patent Explorer
US3551033A Expired / Lapsed US ⏱️ 0.0 years remaining

Quick change filter

Assignee: McDonnell Douglas Corp
•
Filing: 1967-07-03
•
Granted: 1970-12-29
•
Expires: 1987-07-03
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

No abstract record available.

Inventors

  • 👤 Robert L Beesley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 11:01
CPC Classifications
F; F21; F21V; F21V9/00; B; B60; B60Q; B60Q3/00; B60Q3/70; B60Q3/76; B60Q3/80; B60Q3/85; F21V9/02

Claims Analysis

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

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1973-12-28 1974-06-29 1974-12-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1977-12-28 1978-06-29 1978-12-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1981-12-28 1982-06-29 1982-12-29 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag