Skew adjustment mechanism for a window covering

Patent metadata

Field	Value
Publication number	US-9357868-B2
Application number	US-201314089861-A
Country	US
Kind code	B2
Filing date	Nov 26, 2013
Priority date	Dec 6, 2012
Publication date	Jun 7, 2016
Grant date	Jun 7, 2016

Abstract

A skew adjustment method and apparatus for adjusting the skewed condition of a movable rail of a window covering in which the movable rail is supported by lift cords wrapped around spools. A drive train disconnecting mechanism is used to disconnect a first spool from a second spool, the first spool is rotated relative to the second spool, thereby changing the length of the first lift cord relative to the second lift cord until the movable rail is in the desired position; and then the first and second spools are reconnected so the first and second spools rotate together. An end cap may be used to enable multiple disassemblies and reassemblies of the end cap to access the skew adjustment mechanism. In one embodiment, there are two movable rails, and the lift cords for both movable rails extend through the same rout holes in the covering. Disconnecting the first spool from the second spool may activate a mechanism that prevents the second spool from rotating.

First claim

What is claimed is:

1. A skew adjustment mechanism for adjusting a skewed movable rail in a window covering, comprising:
a movable rail having first and second ends, said movable rail being connected to an expandable covering;
a second rail substantially parallel to said movable rail;
first and second lift cords supporting said movable rail;
first and second rotatable spools, each having an axis of rotation, wherein both of said first and second rotatable spools are located on the same one of said movable and second rails;
wherein said first and second lift cords are connected to said first and second rotatable spools, respectively, and wrap onto and off of the respective rotatable spools as said respective rotatable spools rotate so as to increase and decrease the effective length of said first and second lift cords and to extend and retract the covering;
a drive train also located on said one rail and interconnecting said first and second rotatable spools so said first and second rotatable spools rotate together during normal operation; and
a biased disconnector in said drive train, biased in a first direction, said biased disconnector being responsive to an outside force acting opposite the first direction to temporarily disconnect said first rotatable spool from said second rotatable spool to enable the rotation of one of said first and second rotatable spools relative to the other of said first and second rotatable spools in order to enable changing the effective length of said first lift cord relative to said second lift cord and which re-connects said first and second rotatable spools for normal operation when the outside force is released.

2. A skew adjustment mechanism for adjusting a skewed movable rail in a window covering as recited in claim 1 , wherein said biased disconnector includes a biasing spring acting axially along the axis of rotation of said first rotatable spool.

3. A skew adjustment mechanism for adjusting a skewed movable rail in a window covering as recited in claim 2 , wherein said biased disconnector includes a one-way brake, which permits the first rotatable spool to be rotated in a first direction relative to the second rotatable spool without requiring an outside force acting against the biasing spring.

4. A skew adjustment mechanism for adjusting a skewed movable rail in a window covering as recited in claim 3 , wherein said one-way brake includes a ratchet mechanism.

5. A skew adjustment mechanism for adjusting a skewed movable rail in a window covering as recited in claim 3 , wherein said one-way brake includes a wrap spring.

6. A skew adjustment mechanism for adjusting a skewed movable rail in a window covering as recited in claim 1 , and further comprising a third rotatable spool located on said one rail and a third lift cord supporting said movable rail and connected to said third rotatable spool, and further comprising a spring motor operatively connected to said third rotatable spool so as to keep said third lift cord taut independently of said drive train.

7. A skew adjustment mechanism for adjusting a skewed movable rail in a window covering as recited in claim 1 , and further comprising a third rotatable spool located on said one rail, wherein said first lift cord extends from said first lift spool, to a rail parallel to said one of said movable and second rails and back to said third rotatable spool.

8. A skew adjustment mechanism for adjusting a skewed movable rail in a window covering as recited in claim 1 , and further comprising a third rotatable spool located on said one rail, wherein said second lift cord extends from said second lift spool, to a rail parallel to said one of said movable and second rails and back to said third rotatable spool.

Assignees

• Hunter Douglas

Inventors

• Anderson Richard N
• Haarer Steven R

Classifications

• E06B9/388

  Details of bottom or upper slats or their attachment · CPC title

• E06B2009/3225

  Arrangements to aid the winding of cords rollers · CPC title

• E06B9/262

  with flexibly-interconnected horizontal or vertical strips; Concertina blinds {, i.e. upwardly folding flexible screens} · CPC title

• E06B2009/2625

  Pleated screens, e.g. concertina- or accordion-like · CPC title

• E06B2009/2627

  Cellular screens, e.g. box or honeycomb-like · CPC title