Spring system for roller blinds

Patent metadata

Field	Value
Publication number	US-10138678-B2
Application number	US-201414309499-A
Country	US
Kind code	B2
Filing date	Jun 19, 2014
Priority date	Feb 9, 2009
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

A method of selecting one or more springs for a roller blind is provided. The method may include determining one or more parameters of the blind, determining a torque curve of the blind based on the one or more parameters of the blind, and selecting one or more springs having a wire diameter and a spring diameter. The method may further include determining a length of the one or more springs based on the torque curve, the wire diameter of the one or more springs, and the spring diameter of the one or more springs to ensure the blind operates with a constant operating force.

First claim

What is claimed is:

1. A method of selecting one or more springs for a roller blind, comprising:
providing a roller blind including a roller, a sheet attached to said roller for winding and unwinding from said roller, and a bottom rail;
determining one or more parameters of the blind, including a roller length, a roller outer diameter, a sheet length, a sheet weight, a sheet height, a sheet thickness, and a bottom rail weight;
determining a torque curve of the blind based on the one or more parameters of the blind;
selecting a first spring having a wire diameter and a spring diameter, said first spring being operatively connected to the roller to drivingly rotate the roller in at least one direction of rotation; and
based on the torque curve, the wire diameter of the first spring, and the spring diameter of the first spring, determining a length of the first spring; wherein the wire diameter, the spring diameter, and the length of the first spring are selected to match the torque curve.

2. The method of claim 1 , further comprising:
determining a revised torque curve of the blind based on the one or more parameters of the blind and on an operating torque of the first spring;
selecting a second spring having a wire diameter and a spring diameter, said second spring being operatively connected to the roller to drivingly rotate the roller in at least one direction of rotation; and
based on the revised torque curve, the wire diameter of the second spring, and the spring diameter of the second spring, determining a length of the second spring such that the combination of the first spring and the second spring ensures the blind operates with a constant operating force.

3. The method of claim 2 , wherein the first spring and the second spring have identical lengths.

4. The method of claim 2 , wherein the first spring and the second spring have different lengths.

5. The method of claim 2 , wherein the first spring and the second spring have identical wire diameters.

6. The method of claim 2 , wherein the first spring and the second spring have identical spring diameters.

7. The method of claim 2 , wherein the first spring and the second spring have identical wire diameters and spring diameters.

8. The method of claim 2 , wherein the first spring and the second spring have different wire diameters, spring diameters, or both.

9. The method of claim 1 , wherein determining the one or more parameters comprises:
determining an outer diameter of a roller;
determining a height, a width, a thickness, and a weight of a sheet attached to the roller; and
determining a weight of a bottom rail attached to the sheet.

10. The method of claim 1 , wherein the length of the first spring ensures the blind operates with a constant operating force.

11. The method of claim 1 , further comprising:
operatively coupling a first end of the first spring to a central shaft to limit rotational movement of the first end of the first spring relative to the central shaft;
operatively coupling the second end of the first spring to a rotatable member; and
wherein in use upon rotation of the rotatable member in one direction kinetic energy is stored by the first spring and upon rotation of the rotatable member in an opposite direction kinetic energy stored by the spring may be released to the rotatable member.

12. The method of claim 11 , further comprising:
providing a connector on each end of the central shaft, each of the connectors operable to interchangeably connect either end of the first spring to the roller blind.

13. A method of assembling a roller blind, comprising:
attaching a first end portion of the first spring of claim 1 to a stationary member; and
attaching a second end portion of the first spring of claim 1 to a rotatable member keyed to a roller such that rotation of the roller rotates the rotatable member, wherein kinetic energy is stored by the first spring from the rotatable member upon rotation of the rotatable member in one direction of rotation, and the kinetic energy stored by the first spring is released to the rotatable member upon rotation of the rotatable member in an opposite direction of rotation.

14. The method of claim 13 , further comprising arranging the first spring, the stationary member, and the rotatable member around a stationary shaft.

15. A method of selecting one or more springs for a roller blind, comprising:
providing a roller blind including a roller, a sheet attached to said roller for winding and unwinding from said roller, and a bottom rail;
determining an outer diameter of the roller;
determining a height, a width, a thickness, and a weight of the fabric sheet attached to the roller;
determining a weight of the bottom rail attached to the fabric sheet;
determining a number of springs in the roller blind; and
determining a length of each of the number of springs, the combined length of the number of springs configured to provide the roller blind with a constant operating force in lifting and lowering the sheet.

16. The method of claim 15 , wherein the length of one or more of the number of springs is determined using the following formula:

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Assignees

• Hunter Douglas Ind Bv

Inventors

• Bohlen Jorg
• Koop Lars

Classifications

• E06B9/74

  adapted for selective electrical or manual operation · CPC title

• E06B9/68

  Operating devices or mechanisms, e.g. with electric drive · CPC title

• E06B9/42

  Parts or details of roller blinds, e.g. suspension devices, blind boxes (brackets or adjustable mountings for roller blinds and drawable curtains A47H1/13) · CPC title

• E06B9/62 Primary

  Counterweighting arrangements (E06B9/60 takes precedence) · CPC title