Foldable articles

Claim 1

A foldable article comprising a structure formed in two halves with each half having a top surface, means hinging the halves together in such a way that they can be folded from an open position to a closed position in which the respective top surfaces of two halves lie against and face one another, an elongate member spaced from each half, means coupling the ends of the two elongate members together, a rigid coupling member on which the means hinging the two halves and the means coupling the two elongate members are pivotally mounted, two leg members each pivotally connected at one end to a respective half and intermediate its ends to a respective elongate member and spaced from the rigid coupling member, the lines joining the pivot points of a leg member to a half and to a respective elongate member and the pivot points of the hinging means And coupling means of the half and the elongate member respectively in the rigid coupling member forming a parallelogram, the pivotal axes of said pivot points being parallel, the leg members serving as means for supporting the article and each carrying at its lower end enabling means enabling the lower end of the leg member to be moved over a supporting surface, said coupling means including an operable couple operable to provide that, when the article is in an open position and one end is lifted, the other end is constrained to move with a motion of equal magnitude and opposite sense and the two leg members move towards one another on said enabling means, the distance between the pivot point of each supporting leg in the elongate member and the end of the supporting leg being such that when the structure is folded so that the top surface of one half lies up against the top surface of the other half, the coupled ends of the elongate members do not impede movement of the structure over the supporting surface on said enabling means.