Counterbalancing mechanism for an overhead door
US5632063A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 1994 |
| Grant date | May 27, 1997 |
| Priority date | — |
| Expiry date | Jun 16, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S16/07
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An overhead door apparatus utilizing a torsion spring counterbalancing mechanism. The counterbalancing mechanism includes a worm drive ring-shaped gear winding mechanism for setting the appropriate torque or number of winds in the spring. A counting mechanism is provided to indicate to the installer the number of winds being given to the spring. The ring-shaped gear is a spur gear which is formed integrally with the fitting or cone which attaches by way of a threaded connection with one end of the spring. Means are also provided for accommodating spring growth and contraction during winding and unwinding using the winding mechanism and during normal raising and lowering of the door. A spring clip gear retainer is disclosed for preventing rotation or creep of the worm drive gear and spur gear during normal raising and lowering of the door.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.