Patent · US Expired

Shell structure for use with a chair having synchronously moving seat and seat back

US5314240A · kind A · utility

98Cited by
11References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 27, 1991
Grant dateMay 24, 1994
Priority date
Expiry dateDec 27, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S297/02
  • WIPO fieldFurniture, games
  • WIPO sectorOther fields

Abstract

A shell for a chair in which a bottom shell structure and a backrest shell structure are connected to supporting frame members such that when a light load is applied to the separate backrest shell the backrest shell will bend to accommodate the load, whereas when a heavy load is applied to the backrest shell the backrest bends and the supporting bars rock backwards. The bottom shell structure has a bottom portion and a partial backrest portion which are integrally formed on the same material and are connected by a curved portion with plural slots. Sideways notches are connected to the extreme left and right slots and extend toward the left and right edges of the shell structure. The edges of the shell adjacent the notches are curved into a U shape. This construction increases the flexibility of the curved portion, while maintaining a significant portion of the unslotted material strength. A separate shell structure is attached to supporting bars and forms the remainder of the backrest support. This separate shell structure has a jagged cross sectional shape where substantially parallel projections and recesses form grooves which extend the length of the backrest shell.

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