Claims
- 1. A covering for an architectural opening comprising:
a headrail, a bottom rail, an intermediate rail, blind material interconnecting said bottom and intermediate rails, said blind material having a plurality of horizontally disposed slats that are pivotal about longitudinal axes when said blind material is moved between open and closed positions, a control system in said headrail operably connected to said intermediate rail to raise and lower said intermediate rail relative to said headrail, and a counterbalanced system operably interconnecting said headrail and bottom rail to selectively permit movement and positioning of said bottom rail relative to said headrail whereby the spacing between said intermediate rail and said bottom rail is adjustable to extend or retract said blind material.
- 2. The covering of claim 1 wherein said counterbalanced system includes a spring and a lift cord system, said lift cord system interconnecting said bottom rail with said spring such that said spring substantially offsets the weight of said bottom rail so that said bottom rail can be movably positioned at any selected position across said architectural opening.
- 3. The covering of claim 2 wherein said lift cord system includes one or more cords and at least one spool around which said one or more cords can be wrapped, said one or more cords interconnecting said spool and said bottom rail, said spring biasing said spool in a rotative direction to counterbalance the bias placed on said spool by the weight of said bottom rail.
- 4. The covering of claim 3 wherein there are a pair of spools and a pair of cords, each cord interconnecting a spool with one end of said bottom rail such that the ends of the bottom rail move vertically in unison as the cords are wrapped onto or off of said spools.
- 5. The covering of claim 3 or 4 further including a fixed pin associated with each spool and each cord, and wherein said cord is at least partially wrapped around said pin between said spool and said bottom rail.
- 6. The covering of claim 5 wherein there are a plurality of said pins associated with each cord and each spool.
- 7. The covering of claim 1 wherein said intermediate rail has opposite longitudinal edges and wherein said control system includes at least one cord of a second lift cord system and at least one spool around which said at least one cord can be wrapped and unwrapped, an operating system for selectively rotating said spool, said at least one cord further being operatively connected to said opposite longitudinal edges of said intermediate rail such that manipulation of said at least one cord causes said intermediate rail to (1) pivot about a horizontal longitudinal axis and (2) be raised or lowered within said architectural opening.
- 8. The covering of claim 7 further including a releasable brake for selectively preventing rotation of said spool.
- 9. The covering of claim 8 wherein said brake includes a trigger arm for sensing tension in said cord and wherein said trigger arm is operative to release said brake or set said brake dependent on the tension in said cord.
- 10. The covering of claim 9 wherein said spool is mounted for reversible rotation about an axis of rotation and further including a system for moving said spool linearly along said axis of rotation upon rotative movement of said spool.
- 11. The covering of claim 10 wherein said system for moving said spool linearly includes a threaded rod.
- 12. The covering of claim 7 wherein rotation of said spool in one direction causes said intermediate rail to pivot in one direction and be raised in said architectural opening and rotation of said spool in an opposite direction causes said intermediate rail to pivot in an opposite direction and be lowered in said architectural opening.
- 13. The covering of claim 7 or 8 further including a two-way clutch to selectively prevent rotation of said spool in either direction until said operating system is operated to rotate said spool.
- 14. The covering of claim 7, 9, 10, 12 or 13 wherein said intermediate rail has opposite ends, and there are two cords with each cord operatively connected to an opposite end of said intermediate rail.
- 15. The covering of claim 14 further including a pair of pins at each end of said intermediate rail with one of said pins being associated with one longitudinal edge of said intermediate rail and the other of said pins being associated with the other longitudinal edge of said intermediate rail, and wherein each cord is wrapped around each pin at its associated end of the intermediate rail.
- 16. The covering of claim 7 further including at least one roller for compressing said cord onto said spool.
- 17. The covering of claim 15 wherein said one cord has two ends with one end operatively anchored in a static position to said headrail and the other end anchored to said spool, and further wherein said cord as it passes from said spool to said static anchored position is just wrapped around said one pin and then around said other of said pins.
- 18. The covering of claim 15 wherein said one cord has two ends with one end operatively anchored in a static position to said headrail and the other end anchored to said spool, and further wherein said cord as it passes from said spool to said static anchored position is first wrapped around said other of said pins and then around said one pin.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. application Ser. No. 10/393,698, filed 18 Mar. 2003, which application claims the benefit of U.S. provisional application No. 60/366,286, filed 20 Mar. 2002. Each of the above-identified applications is hereby incorporated by reference as if fully disclosed herein.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60366286 |
Mar 2002 |
US |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
10393698 |
Mar 2003 |
US |
Child |
10642017 |
Aug 2003 |
US |