Interconnection of toy building elements in a releasable secure engagement

Abstract

Square and octagonal building elements for a set of toy building elements that are capable of being inteconnected in a releasable engagement both side-to-side and top-to-bottom. The side walls of the building elements include a groove and/or a split flexible tongue that is compressed when frontally forced into a groove in another such building element to effect a releasable restraining frictional engagement within the groove. The degree of frictional engagement provided by compression of the tongue when a distal portion of the tongue resides in a base region of the groove is such as to enable a stationary relative disposition of a pair of so engaged building elements to be varied precisely by smoothly sliding the tongue of one of the pair of engaged building elements within the groove of the other of the pair of engaged building elements, and also is such as to provide enough resistance to sliding as to maintain the stationary relative disposition when one of the pair of engaged building elements has the top of its engaged side wall disposed at a greater height than the top of the engaged side wall of the other of the pair of building elements. The tongues and the grooves are also dimensioned so that less force is required to effect engagement by frontally pressing the building elements together than is required to effect disengagement by frontally pulling the building elements apart.