1. Field of the Invention
The subject invention pertains generally to collapsible carts or tray stands and more particularly to X-frame type carts having crossing support legs which diverge into a free-standing configuration.
2. The Prior Art
Folding carts or tray stands are well known. Typically, available carts are of metallic construction and include a crossing pair of support legs at each side. Each pair of support legs consists of an outwardly and an inwardly disposed leg pivotally coupled at their mid-sections. Lower ends of the legs, which extend from the mid-sections, can selectively diverge into a free-standing configuration or converge into a storage position.
Such carts commonly provide a shelf extending transversely between and supported by the crossing side legs. The shelf can be of fabric or of solid construction. With carts having a fabric shelf, the fabric is stretched between the support legs upon divergence of the legs and functions to limit such divergence at the free-standing position. Alternatively, in carts having solid shelves, the shelf is typically hinged to a first cross member so as to swing into a horizontal orientation for connection to a second cross member as the support legs assume the free-standing position. Again, the shelf acts to brace the cart against inadvertent collapse and serves to retain the support legs in the free-standing position.
While the aforementioned carts function well, certain deficiencies make available carts less than optimal. First, the crossing support legs and casters do not lie in a common plane, which increases the overall width of the cart. Such carts are thereby more cumbersome to manuever.
Secondly, the support and structural rigidity provided by the shelf member to the support legs in the extended free standing condition is inadequate. Inadvertent contact between the cart and obstructions can initiate its collapse, particularly with fabric shelves which provide little resistance to convergence of the support legs. Inadequate structural bracing of the support legs sharply limits the load which can be supported.
Finally, available carts or stands are relatively expensive to manufacture, relying as they must upon metal components for structural integrity.
USPTO Backgrounds
USPTO Backgrounds