Hold-open apparatus for door
Abstract
Abstract THE APPARATUS CONTROLS AXIAL MOVEMENT OF A SHAFT LONGITUDINALLY OF ITS OWN AXIS, WHICH SHAFT IS ARRANGED FOR AXIAL MOVEMENT IN RESPONSE, RESPECTIVELY, TO OPENING AND CLOSING MOVEMENT OF A DOOR UPON A FIXED HINGE AXIS. A BOSS HAVING A CAMMING SURFACE IS MOUNTED IN A FIXED AXIAL POSITION ALONG THE SHAFT. OWING TO A HOLDING ARRANGEMENT OF AN EXPANDABLE GROUP OR RING OF BALLS ENCIRCLING THE SHAFT, WHICH BALLS ARE ACTED UPON BY RESILIENT MEANS, AN AXIAL PULLING FORCE ON THE SHAFT IS REQUIRED TO PERMIT AXIAL MOVEMENT OF ITS CAMMING BOSS THROUGH THE RING OF BALLS WHEN THE SHAFT MOVES IN A DOOR CLOSING DIRECTION. BECAUSE OF THE CONFIGURATION OF THE BOSS OR CAM, A LESSER AXIAL PULLING FORCE ON THE SHAFT SUFFICES TO PERMIT AXIAL MOVEMENT OF THE CAM THROUGH THE RING OF BALLS, WHEN THE SHAFT IS MOVING IN A DOOR OPENING DIRECTION.
Inventors
- 👤 Burke J Crane
Bibliographic Details
Claims Analysis
Total Claims: 0References 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) | 1974-02-08 | 1974-08-10 | 1975-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-08 | 1978-08-10 | 1979-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-08 | 1982-08-10 | 1983-02-09 | $7700.00 | Window Closed / Lapsed |