| 主权项 |
1. An elongated double-fold foldable structural truss having a quadrilateral framework extending along a longitudinal direction, the structural truss being movable between a folded position and an unfolded position, and including:
four chord beam units disposed parallel to one another, each chord beam unit being located at a corresponding corner of the quadrilateral framework and having four sides, two of the sides being inner sides and two of the sides being outer sides, each inner side facing a corresponding one of the inner sides of another one of the chord beam units of the structural truss, each chord beam unit including:
two spaced-apart and juxtaposed beams running parallel to one another, the beams defining between them a first open channel extending substantially along an entire length of the structural truss, the first open channel being opened on one of the inner sides of the chord beam unit, the chord beam unit having a second open channel on the other one the inner sides of the chord beam unit, the second open channel extending substantially along the entire length of the structural truss;a plurality of first pivot joints extending transversally in-between the two spaced-apart beams and across the first open channel, the first pivot joints having first pivot axes that are parallel to one another and that are perpendicular to the longitudinal direction; anda plurality of second pivot joints extending perpendicularly across the second open channel, the second pivot joints having second pivot axes that are parallel to one another, that are perpendicular to the longitudinal direction and that are perpendicular to the first pivot axes of the chord beam unit; and four web units, each including a plurality of brace members interconnecting two corresponding ones of the chord beam units, the brace members of two of the web units having opposite ends that are pivotally connected to corresponding ones of the first pivot joints and the braces members of two of the web units having opposite ends that are pivotally connected to corresponding ones of the second pivot joints, the brace members of at least two of the web units being telescopic, each telescopic brace member including two sections in telescopic engagement with one another and being movable between a retracted position and an extended position, the telescopic brace members being all in their extended position when the structural truss is in its unfolded position and being all in their retracted position when the structural truss is in its folded position, all brace members extending at least partially inside a corresponding one of the open channels when the structural truss is in its folded position. |
