This invention relates to boxes of chipboard or the like, supplied folded flat for filling and closing by means of side tabs and a top having a tongue that slides into the box and is provided with notches for locking the top in closed position. The invention is especially directed to such boxes in which the side tabs, as well as the top flap interlock to provide a more secure closure.
The object of the invention is to improve the side tab interlocking means to largely avoid the commonly experienced problem of tearing the portions of the side tabs intended to lock them together as the box is being closed so that a large proportion of the boxes are rendered useless and are discarded.
More specifically, the invention provides an interlocking arrangement which can be readily assembled without straining the box material and which securely locks the entire top closure structure together.