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US3555591A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Friction-type door check
Assignee: Individual
•
Filing: 1968-06-25
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Granted: 1971-01-19
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Expires: 1988-06-25
Abstract
Abstract A DOOR CHECK FORMED OF A TUBULAR HOUSING WITH SPRINGS, A FRICTION RETARDING ELEMENT, AND A CONE-SHAPED WEDGE THEREIN IN WHICH ONE END OF THE HOUSING IS PIVOTALLY HELD TO THE DOOR FRAME. A ROD EXTENDING FROM THE OTHER END IS PIVOTALLY ATTACHED TO THE DOOR. AS THE DOOR IS OPENED THE SPRING IS READILY COMPRESSED, AND AS THE DOOR IS RELEASED THE SPRING AUTOMATICALLY CLOSES THE DOOR AND AT THE SAME TIME FORCES THE WEDGE INTO THE FRICTION ELEMENT WHICH BEARS AGAINST THE INNER SURFACE OF THE HOUSING RETARDING THE CLOSING OF THE DOOR. A SECOND SPRING IS PROVIDED FOR MAINTAINING THE FRICTION RETARDING ELEMENT AGAINST THE WEDGE DURING THE OPENING OF THE DOOR.
Inventors
- 👤 Nash P Sogoian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:00
CPC Classifications
E; E05; E05F; E05F3/00; E05F3/16; E05Y; E05Y2900/00; E05Y2900/10; E05Y2900/13; E05Y2900/132
Claims Analysis
Total Claims: 0
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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) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |