US2171587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Instrument for making perspective drawings from plan and elevation
Assignee: Individual
•
Filing: 1937-06-23
•
Granted: 1939-09-05
•
Expires: 1957-06-23
Abstract
No abstract record available.
Inventors
- 👤 Donald T Mcgregor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:55
CPC Classifications
B; B43; B43L; B43L13/00; B43L13/14; B43L13/148
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) | 1942-09-04 | 1943-03-06 | 1943-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-09-04 | 1947-03-06 | 1947-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-09-04 | 1951-03-06 | 1951-09-05 | $7700.00 | Window Closed / Lapsed |