US3721343A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of checking card file activity
Assignee: Mosler Safe Co
•
Filing: 1971-05-21
•
Granted: 1973-03-20
•
Expires: 1991-05-21
Abstract
Abstract THE ACTIVITY OF EDGE CODED CARDS STORED IN A STORAGE COMPARTMENT OF A FILE IS CHECKED BY ALWAYS RETURNING CARDS TO THE FILE AT THE SAME RELATIVE POSITION IN THE STORAGE COMPARTMENT. A DISTINCTIVE DUMMY CARD INSERTED INTO THE COMPARTMENT AT THE INFILE POSITION ENABLES CARDS THEREAFTER SELECTED, USED AND RETURNED TO THE FILE TO BE ISOLATED ON ONE SIDE OF THE DUMMY CARD FROM THE UNSELECTED CARDS. THEREFORE, ANY CARDS STILL ON THE UNSELECTED CARD SIDE OF THE DUMMY CARD AFTER A SPECIFIED PERIOD HAVE NEVER BEEN USED AND MAY, IF SO DESIRED, BE PURGED FROM THE FILE AS ABSOLETE OR INACTIVE.
Inventors
- 👤 L Mustain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:47
CPC Classifications
G; G06; G06K; G06K17/00; G06K17/0003; G06K17/0009
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) | 1976-03-19 | 1976-09-18 | 1977-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-19 | 1980-09-18 | 1981-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-19 | 1984-09-18 | 1985-03-20 | $7700.00 | Window Closed / Lapsed |