US 12,345,094 B2
Balanced spring-loaded roller blind, and a torsion spring, a method, and a system therefor
Jean-Sébastien Binette, Montréal (CA)
Filed by Jean-Sébastien Binette, Montréal (CA)
Filed on Feb. 16, 2022, as Appl. No. 17/673,321.
Prior Publication US 2023/0258040 A1, Aug. 17, 2023
Int. Cl. E06B 9/42 (2006.01); E06B 9/60 (2006.01)
CPC E06B 9/42 (2013.01) [E06B 9/60 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method of making a roller blind for selectively covering a window having a known height thereof, the method comprising:
providing a cylindrical rotatable roller;
mounting a sheet to the roller for being rolled thereon and unrolled therefrom during rotation of the roller between a first position at which the sheet is fully rolled about the roller and a second position wherein a hanging portion of the sheet hangs from the roller in order to fully cover the window height, the sheet comprising a rolled portion thereof that is rolled about the roller between the first and second positions thereby defining a roll with the roller, the roll defining a lateral circular profile defining a roll radius that varies in diameter between the first and second positions, wherein the hanging portion of the sheet comprises a varying weight thereof between the first and second positions;
mounting a torsion assembly to the roller, the torsion assembly comprising a rotatable torsion spring fitted within the roller for being rotated thereby during rolling and unrolling movement of the sheet between the first and second positions to provide a spring force in a direction opposite the rotational direction of the roller from the first to the second positions, wherein the blind provides a blind force on the spring that is a function of the varying weight of the sheet hanging portion multiplied by the varying radius of the roll between the first and second positions;
determining the weight of a strip of the sheet that is unrolled from the roll at a one radian rotation of the roller, wherein the weight of the strip comprises a numerical value; and
providing for the spring to have a spring constant thereof that has a numerical value equal to the numerical value of the weight of the strip at the one radian rotation between the first and second positions thereby providing for the blind force to be equal to the spring force between the first and second positions thereby balancing the roller blind.