US 7,320,503 B2
Backrest for seats and chairs having pressure and tensile elements
Volker Wilhelm Eysing, Kiel (Germany)
Assigned to Volker W. Eysing, Kiel (Germany); and Provenda Marketing AG, Sennwald (Switzerland)
Filed on Jul. 06, 2005, as Appl. No. 11/175,028.
Claims priority of application No. 10 2004 032 765 (DE), filed on Jul. 06, 2004; application No. 20 2004 018 712 U (DE), filed on Dec. 02, 2004; and application No. 0277/05 (CH), filed on Feb. 16, 2005.
Prior Publication US 2006/0033369 A1, Feb. 16, 2006
Int. Cl. A47C 7/02 (2006.01)
U.S. Cl. 297—452.63  [297/452.15; 297/452.29; 297/440.2; 297/285] 46 Claims
OG exemplary drawing
 
1. A backrest with a support area extending from a first and lower end region to a second and top end region for supporting the back of a user, said backrest comprising:
at least one mounting element for mounting the backrest to a backrest bracket, said at least one mounting element being arranged between the end regions at a distance from the first end region and at a distance from the second end region of the support area, and
at least one extended structure with a tension element at the front side of the structure and a pressure element at its rear side, both the tension element and the pressure element extending from the first end region of the support area to the second end region of the support area,
whereby
the tension element connects the first end region of the support area to the second end region of the support area thereby transmitting tensile forces, and
the pressure element is in the extension direction non-displaceably connected to the tension element as well in the first end region of the support area as in the second end region of the support area,
the pressure element between the first end region and the second end region is arranged at a distance from the tension element and can take thrust forces,
between the end regions the tension element and the pressure element are connected to one another by means of spacers, which spacers keep the distance between the pressure element and the tension element and allow a relative movement between the tension element and the pressure element in the extension direction of the structure, and
the spacers together with the tension element and the pressure element in a cross section in the extension direction form a polygon structure, said structure having angles that are deformed by loading.