Patent · US Expired

Extension spring system for an overhead door

US5615723A · kind A · utility

33Cited by
41References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 5, 1995
Grant dateApr 1, 1997
Priority date
Expiry dateMay 5, 2015

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.