Cordless blinds

Abstract

A window blind assembly includes a headrail having a longitudinal axis extending between first and second ends thereof, a first tube rotatably mounted between the first and second ends of the headrail and a second tube rotatably mounted between the first tube and the second end of the headrail. The assembly also has a bottom rail suspended below the headrail, an intermediate rail suspended below the headrail and positioned between the headrail and the bottom rail, and a window covering material extending between the intermediate rail and the headrail, the window covering material having an upper end attached to the intermediate rail and a lower end attached to the bottom rail. The assembly further includes a first lift cord having an upper end secured to the first tube and a lower end secured to the intermediate rail, and a second lift cord having an upper end secured to the second tube and a lower end secured to the bottom rail, whereby the intermediate rail and the bottom rail are movable independently of one another.

1 . A cordless window blind assembly comprising: 
 a headrail having a longitudinal axis extending between first and second ends thereof;    a first tube rotatably mounted between the first and second ends of said headrail;    a second tube rotatably mounted between said first tube and the second end of said headrail, wherein said first and second tubes rotate independently of one another;    a bottom rail suspended below said headrail by lift cords;    a window covering material extending between said headrail and said bottom rail;    said lift cords including a first lift cord having an upper end secured to said first tube and a lower end secured to said bottom rail and a second lift cord having an upper end secured to said second tube and a lower end secured to said bottom rail.    
     
     
         2 . The assembly as claimed in  claim 1 , wherein said window covering material has an upper end attached to said headrail and a lower end attached to said bottom rail.  
     
     
         3 . The assembly as claimed in  claim 1 , further comprising: 
 a third lift cord having an upper end secured to said first tube and a lower end secured to said bottom rail; and    a fourth lift cord having an upper end secured to said second tube and a lower end secured to said bottom rail.    
     
     
         4 . The assembly as claimed in  claim 1 , further comprising: 
 a first guide connected to said headrail and being adapted to direct said first lift cord through a path including a first leg extending away from said first tube, a second leg extending away from said first tube and toward said second tube, and a third leg extending away from said second tube and toward said bottom rail; and    a second guide connected to said headrail and being adapted to direct said second lift cord through a path including a first leg extending away from said second tube, a second leg extending away from said second tube and toward said first tube, and a third leg extending away from said first tube and toward said bottom rail.    
     
     
         5 . The assembly as claimed in  claim 1 , wherein the first leg of said first lift cord extends in a direction generally perpendicular to the longitudinal axis of said headrail, the second leg of said first lift cord extends in a direction generally parallel to the longitudinal axis of said headrail and the third leg of said first lift cord extends in a direction generally perpendicular to the longitudinal axis of said headrail, and 
 wherein the first leg of said second lift cord extends in a direction generally perpendicular to the longitudinal axis of said headrail, the second leg of said second lift cord extends in a direction generally parallel to the longitudinal axis of said headrail and the third leg of said second lift cord extends in a direction generally perpendicular to the longitudinal axis of said headrail.    
     
     
         6 . The window blind assembly as claimed in  claim 1 , wherein said first guide comprises a cradle mounted in said headrail for supporting rotation of said first tube and a cord guide attached to said window covering material, and wherein said second guide comprises a second cradle mounted in said headrail for supporting rotation of said second tube and a second cord guide attached to said window covering material.  
     
     
         7 . The assembly as claimed in  claim 1 , further comprising a third lift cord extending between said first tube and said bottom rail in a direction substantially perpendicular to the longitudinal axis of said headrail and a fourth lift cord extending between said second tube and said bottom rail in a direction substantially perpendicular to the longitudinal axis of said headrail.  
     
     
         8 . The assembly as claimed in  claim 7 , wherein said third lift cord has an upper end secured to said first tube and said fourth lift cord has an upper end secured to said second tube.  
     
     
         9 . The assembly as claimed in  claim 1 , further comprising: 
 a first threaded support rod disposed in said headrail and threadably coupled with said first tube for providing traversing movement to said first tube; and    a second threaded support rod disposed in said headrail and threadably coupled with said second tube for providing traversing movement to said second tube, wherein said first and second tubes are movable independently of one another between the first and second ends of said headrail.    
     
     
         10 . The assembly as claimed in  claim 1 , wherein said first motor is a first spring motor disposed in said headrail and coupled with said first tube for driving said first tube, wherein said first tube traverses between the first and second ends of said headrail when being driven by said first spring motor; and 
 said second motor is a second spring motor disposed in said headrail and coupled with said second tube for driving said second tube, wherein said second tube traverses between the first and second ends of said headrail when being driven by said second spring motor.    
     
     
         11 . The assembly as claimed in  claim 10 , wherein said first and second spring motors include drive gears that rotate about axes that are substantially parallel to the longitudinal axis of said headrail.