Stackable transport container

Claim 1

A stackable transport container comprising a one-piece container blank which can be flattened when not in use, having a quadrilateral bottom and four walls extending from the bottom in an upward and outwardly inclined direction to define a container space widening in an upward direction, stack supports formed of portions of the container blank wall portions which are adapted to be pushed into the container space and pushed back out of the container space, being provided at four corners of the container space in the erected condition of the container and having their upper edges located at a level that is lower than the upper edges of the adjacent portions of the walls of the container, said stack supports being formed of quadrilateral container blank portions which are in connection with the adjacent wall portions of the container along folding lines, all of said folding lines being located in a vertical position in the erected condition of the container and diverging from each other toward the upper edges of the stack support, said blank portions of each container space corner defining together with the imaginary extensions of the side walls of the container in the erected condition of the container a cavity that tapers in a downward direction and that extends from the upper end of the stack support to its lower end, the upper end of said cavity being open, and an insert member of rigid material being provided for each of said container space corners that is inserted in or removed from the cavity of each stack support, said insert member, when inserted in the cavity, resting on the bottom of the container and having a base body and a supporting surface extending above the upper edge of the stack support but being located at a level that is lower than the upper edges of the adjacent portions of the side walls of the container, so that, in use, with an upper container being stacked on a lower container, said supporting surface supports the bottom of an immediately overlying container within a stack and the upper edges of the walls of the lower container prevent the upper container from lateral sliding movement relative to the lower container, the surfaces of each insert member contacting the walls of said stack supports, and each insert member, when in position, gripping an inwardly folded flap of the container and thereby locking the container blank in the erected position thereof.