Locking join for boxes
OwnerStephen E. McGrathinventor
Life of this patent
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Abstract
A non-releasable mechanical join useful for permanent joins of plastics material cartons is formed by a row of a plurality of engagement tabs interlocked in a complementary row of slots. The engagement tabs have heads able to pass through the slots in one direction but unable to return in the other direction. The tab heads may be formed as arrowheads, the barbs of which act against edges of the slots are convexly arcuate towards the approaching arrowheads. This may help to provide secure engagement. The greater number of tabs and slots, the greater may be the permanence of the join.
Claims8
In a carton formed of resilient plastics material, a mechanical joint between first and second plastics material panels;
- the first panel having a first edge and a first margin bordering said first edge, a plurality of aligned, spaced apart slots being provided in the margin parallel to the first edge, each the said slots each having a prechosen length;
- the second panel having a second edge and having a corresponding plurality of tabs projecting from the second edge;
- each one of said tabs having a neck portion and a tab head,
- each one of said tab heads having a leading insertion tip having a width less than said prechosen length, and said each one of said tab heads having a trailing non-return edge having a length greater than said prechosen length;
- said tabs being engaged in said slots with the neck portions extending through the slots so that the tab heads lie flush with one side of the first margin and the second edge lies against another surface of the first margin.
Dependencies are inferred from the claim text.