Patent · US Expired

Elastic column of adjustable length

US4096785A · kind A · utility

7Cited by
7References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 21, 1976
Grant dateJun 27, 1978
Priority date
Expiry dateJun 21, 1996

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA47C3/30
  • WIPO fieldFurniture, games
  • WIPO sectorOther fields

Abstract

A column including a cylinder, a piston axially slidable in the cylinder cavity, a piston rod axially projecting from the cylinder, and a valve permitting selective communication between the two compartments of the cylinder cavity separated by the piston for flow of fluid between the compartments is additionally provided with a helical compression spring coiled about the piston rod and impeding axial movement of the piston on the piston rod in one direction, movement in the other direction being limited by a radial abutment flange on the piston rod. The spring favorably affects the comfort of a chair whose seat is mounted on the column.

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