Spring system for roller blinds

Patent metadata

Field	Value
Publication number	US-10030442-B2
Application number	US-201414309571-A
Country	US
Kind code	B2
Filing date	Jun 19, 2014
Priority date	Feb 9, 2009
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

A spring assist module for window covering includes a stationary member, at least one torsion spring, and at least one rotatable member. The stationary member may be connectable to an operating member of the window covering. The at least one rotatable member may be keyable to a driven part of the window covering, such that rotation of the driven part rotates the at least one rotatable member. The at least one torsion spring may include a first end operatively coupled to the stationary member and a second end operatively coupled to the at least one rotatable member. The spring assist module may be pre-assembled as a self-contained unit.

First claim

What is claimed is:

1. A spring assist module for a covering for an architectural opening, the spring assist module comprising:
a central member connectable to an operating member of the covering;
at least one torsion spring including a first end and a second end; and
at least one non-rotatable member non-rotatably coupled to the central member, the first end of the at least one torsion spring being operatively coupled to the at least one non-rotatable member;
at least one rotatable member keyable to a driven part of the covering such that rotation of the driven part rotates the at least one rotatable member, the second end of the at least one torsion spring being operatively coupled to the at least one rotatable member;
wherein:
kinetic energy is stored by the at least one torsion spring from the at least one rotatable member upon rotation of the at least one rotatable member in one direction of rotation;
the kinetic energy stored by the at least one torsion spring is released to the at least one rotatable member upon rotation of the at least one rotatable member in an opposite direction of rotation;
the at least one torsion spring is selected according to a protocol such that its length ensures that it drives the driven part with a constant operating force; and
the protocol is arranged to calculate a torque curve for the covering, and to calculate the length of the at least one torsion spring as a function of: a number of springs of the at least one torsion spring; an outer diameter of the driven part; at least one of a size parameter or a weight parameter associated with at least one of a fabric of the covering or a bottom rail of the covering; and an assumed torque increase of the at least one torsion spring with respect to a corresponding assumed spring length of the at least one torsion spring.

2. The spring assist module of claim 1 , wherein the central member remains stationary during rotation of the rotatable member.

3. The spring assist module of claim 2 , wherein the at least one torsion spring concentrically surrounds the central member.

4. The spring assist module of claim 1 , wherein the central member is a shaft with a continuous unround profile.

5. The spring assist module according to claim 1 , further comprising an electrically powered drive motor operatively arranged between the central member and the at least one rotatable member.

6. The spring assist module according to claim 1 , wherein:
each end of the central member includes a connector operable to interchangeably connect either end of the spring assist module to the covering; and
the connector on each end of the central member keeps the central member stationary with respect to the covering with which it is adapted to cooperate.

7. The spring assist module according to claim 6 , wherein the connector on each axial end of the central member is configured to maintain the integrity of the spring assist module as a self-contained unit.

8. The spring assist module of claim 1 , wherein the at least one torsion spring comprises at least two torsion springs having equal lengths, and wherein the at least two torsion springs in combination drive the covering with the constant operating force.

9. The spring assist module of claim 8 , wherein the at least two torsion springs have identical wire diameters and spring diameters.

10. The spring assist module of claim 8 , wherein the at least two torsion springs have different wire diameters and spring diameters.

11. The spring assist module of claim 1 , wherein the at least one torsion spring comprises at least two torsion springs having different lengths, and wherein the at least two torsion springs in combination drive the covering with the constant operating force.

12. The spring assist module of claim 11 , wherein the at least two torsion springs have identical wire diameters and spring diameters.

13. The spring assist module of claim 11 , wherein the at least two torsion springs have different wire diameters and spring diameters.

14. The spring assist module of claim 1 , wherein the number of springs of the at least one torsion spring is determined by 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

• E06B9/62 Primary

  Counterweighting arrangements (E06B9/60 takes precedence) · 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