Patent · US Expired

Sash counterbalance leveling device

US5216782A · kind A · utility

11Cited by
1References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 11, 1992
Grant dateJun 8, 1993
Priority date
Expiry dateMay 11, 2012

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE05F15/665
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A sash counterbalance device for a fume hood including a first cable having a first end and a second end, the first end being secured on the left side of a fume hood sash and wherein a first counterweight is secured on the second end of the first cable; a second cable having a first end and a second end, the first end of the second cable being secured on the right side of the sash, and wherein a second counterweight is secured on the second end of the second cable; and an axle which is mounted on the fume hood. The first and second cables are individually, separably, and concentrically wrapped about the axle such that movement of the sash causes a simultaneous movement of the axle by movement of the counterweights axle in a predetermined direction. The rotation of the axle synchronizes the movement of the first and second cables thereby causing the left and right sides of the sash to move vertically and in correspondingly equal amounts within a fume hood access opening thereby preventing the sash from becoming lodged within the access opening.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.