Spring system for roller blinds
AssigneeHunter Douglas Industries BV
InventorsJorg Bohlen, Lars Koop
Life of this patent
Estimating the term…
Abstract
A roller blind including a roller of having a roller length and a roller outer diameter, a fabric attached to said roller for winding and unwinding from said roller. The fabric has a fabric length, a fabric weight, a fabric height, and fabric thickness. The blind includes a bottom bar having a bottom bar weight, and at least one spring operatively connected to the roller to drivingly rotate the roller in at least one direction of rotation. The spring is selected according to a Protocol such that it's length ensures that it drives the roller with a constant operating force.
Claims30
A roller blind including
- a roller having a roller length and a roller outer diameter,
- a fabric attached to said roller for winding and unwinding from said roller,
- the fabric having a fabric length, a fabric weight, a fabric height, and fabric thickness,
- a bottom bar having a bottom bar weight,
- and at least one helically wound torsion spring operatively connected to the roller to drivingly rotate the roller in at least one direction of rotation
- wherein the spring is selected according to a Protocol such that its length ensures that the blind operates with a constant operating force.
A spring assist module for window covering, the module including
- a stationary carrier connectable to an operating member of the window covering;
- at least one helically wound torsion spring having a first and a second spring end;
- at least one rotatable member to be keyed to a driven part of the window covering, such that rotation of the driven part rotates the rotatable member and;
- the torsion spring having a first end operatively coupled to the stationary carrier and a second end operatively coupled to the rotatable member;
- whereby in use upon rotation of the rotatable member in one direction of rotation kinetic energy may be stored by the torsion spring from the rotatable member and upon rotation of the rotatable member in an opposite direction of rotation any kinetic energy stored by the torsion spring may be released to the rotatable member and wherein the spring assist module is pre-assembled as a self-contained unit.
Dependencies are inferred from the claim text.