Patent attributes
A half spread folding door is comprised of plural door leaves; door frames supporting each door leaf in both side ends thereof; a hinge means for connecting successively each door leaf with adjacent door leaf along its width direction, a pair of hinge means are lengthwise each mounted in both side ends of the door leaf and plural hinge means are lengthwise mounted in the middle of the door leaf, allowing each door leaf to be rotated around a hinge shaft correlatively, and for folding each door leaf toward alternative dead end of the door leaves sequentially; and a spread confining means for limiting relative rotation angles of every door leaves interconnected by the hinge means and a spread range of each door leaf in an angle of 30° to 60° to configure as the form of zigzag when the door leaves are spread. Each door leaf has a form of zigzag when closed, a thinner thickness door than a conventional flat type folding door can be configured using the same property material, which attains the very lighter but highly rigid door. The door can be easily opened/closed and the door leaves can be smoothly folded during its opening operation, adapting to use an opening of large structure or a foldable roof such as large depot and an airshed, etc.
