Block interlocking insert

DETAILED DESCRIPTION I claim: 1.
In a block wall having upper and lower tiers of building block of the type having top and bottom surfaces with walls forming an internal core cavity of generally predetermined width extending therebetween, and with the cavities of the upper and lower tiers being aligned: a long, narrow strip of relatively stiff material having upper and lower surfaces, a width considerably less than that of said predetermined cavity width, and a length greater than said predetermined cavity width positioned between said tiers; said strip having a first upwardly extending U-shaped configuration followed by a first downwardly extending U-shaped configuration positioned longitudinally of each other and lengthwise of said strip, and a second downwardly extending U-shaped configuration and a second upwardly extending U-shaped configuration positioned longitudinally of each other and lengthwise of said strip; said first and second upwardly extendig U-shaped configurations being positioned against the respective opposing vertical core cavity wall surfaces of the upper tier and the first and second downwardly extending U-shaped configurations being positioned against the respective opposing vertical core cavity wall surfaces of the lower tier to key the two tiers together; said strip having end portions positioned between blocks of the upper and lower tiers to hold the blocks of the two tiers apart and provide a space therebetween; and a mortar joint material in said space between said keyed tiers.
2.
The device of claim 1 wherein said upwardly extending U-shaped configurations are spaced apart by a distance greater than said downwardly extending U-shaped configurations to accommodate a taper in the cavity sidewalls of the block.
3.
The device of claim 1 wherein the U-shaped configurations are constructed and arranged to resiliently abut the internal core cavity wall surfaces of blocks for which they are designed.
4.
The device of claim 1 having portions extending outwardly of said abutments, said portions having flanges bent vertically to provide spacing between vertically aligned blocks