Extension spring system for an overhead door
US5577544A · kind A · utility
32Cited by
19References
34Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 10, 1994 |
| Grant date | Nov 26, 1996 |
| Priority date | — |
| Expiry date | Aug 10, 2014 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16F2236/04
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An extension spring overhead door system in which the spring may be quickly and easily placed in tension with the door in a closed position. A spring tensioning device is provided which eliminates the need for multiple installers to lift the full weight of the door and then clamp or otherwise prop the door in an open position. An extension spring containment tube is also provided which surrounds the entire periphery of the spring to fully contain the entire length of the extension spring.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.