| 摘要 |
<p>A routing for a pair of tension cords in a window covering with parallel, top and bottom rails that can be moved vertically along the tension cords, the tension cords: i) being connected by top and bottom pairs of attachment members to top and bottom portions of a window, ii) having middle portions which are attached to either the top or bottom pairs of attachment members, and iii) having end portions which are secured to the other of the top and bottom pairs of attachment members; the cord routing being characterized in that the middle portions are movably looped about the top or bottom pairs of attachment members and the tension cords are connected to each other by a single tension spring, whereby the tension cords are maintained in proper tension to keep the rails parallel when one or both rails are moved vertically along the tension cords</p> |
