Window blind assembly

A Venetian blind assembly comprising:

• an elongated top rail member including lift cord locking means, and an elongated bottom rail member spaced in parallel relation from the top rail member, the bottom rail member being movable toward or away from the top rail member;
• a collapsible ladder and slat structure extending between and interconnecteding the rail members, the structure including a plurality of slats, parallel to each other and to the rail members, and two or more flexible ladders for supporting the slats, the ladders extending between the rail members and being perpendicular to the slats and the rail members, the upper ends of the ladders being connected to the top rail member, the lower ends of the ladders being connected to the bottom rail member;
• two or more lift cords extending between the rails through vertically aligned apertures in the slats, the upper ends of the lift cords being movable through the lift cord locking means, the lower ends of the lift cords having portions contained within the bottom rail member;
• and
• spiral tension spring means contained within the lower rail member for retaining the lower lift cord portions within the bottom rail as the lift cords are manipulated by the user to raise or lower the bottom rail member relative to the top rail member, the spring means being in an unexpanded, untensioned condition when the bottom rail member is free to move toward or away from the top rail member, wherein, when the bottom rail member is held at a fixed distance from the top rail member, the lower portions of the lift cords can be partially pulled from the bottom rail member to expand the spiral tension spring means wherein the spring means applies a tensioning force on the lift cords which can then be locked in position by use of the lift cord locking means, the tensioned lift cords, extending through the apertures in the slats, maintaining and stabilizing the position of the ladder and slat structure.

In a Venetian blind assembly having an elongated top rail member and an elongated bottom rail member spaced in parallel relation from the top rail member, said blind assembly further including a ladder and slat structure extending between and interconnecting the rail members, the structure including a plurality of slats, parallel to each other and to the rail members, and two or more flexible ladders extending between the rail members and being perpendicular to the slats and the rail members, the upper ends of the ladders being connected to the top rail member, the lower ends of the ladders being connected to the bottom rail member, each ladder including a pair of elongated sidepieces interconnected by a plurality of rungs or crosspieces upon which said slats rests, means for connecting each of the bottom ends of the ladders to the bottom rail comprising:

• an annular member located below a portion of the bottom rail, said bottom rail portion being located between the lower ends of the sidepieces, the annular member extending transverse to the elongated bottom rail member, the lower end of one of the sidepieces extending through the annular member from one end thereof, the lower end of the other sidepiece extending through the annular member from the other end thereof, said end pieces being retained within said annular member, said portion of the bottom rail resting upon and being supported by the interconnected lower ends of the sidepieces of the ladder.