US3531981A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Test apparatus to detect restriction in the brake pipe of railway brake systems
Assignee: Westinghouse Air Brake Co
•
Filing: 1968-12-27
•
Granted: 1970-10-06
•
Expires: 1988-12-27
Abstract
No abstract record available.
Inventors
- 👤 Andrew J Pommer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:00
CPC Classifications
B; B60; B60T; B60T17/00; B60T17/18; B60T17/22; B60T17/228
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-10-05 | 1974-04-06 | 1974-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-10-05 | 1978-04-06 | 1978-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-10-05 | 1982-04-06 | 1982-10-06 | $7700.00 | Window Closed / Lapsed |