Tubular key and corresponding lock housing key entry construction

Abstract From the Canadian patent

A tubular key and axial pin tumbler lock construction with an annular keyway wherein the key shank has a plurality of longitudinally extending grooves positioned between the circumferential key cut receiving areas and the lock housing outer periphery of the key entry way is provided with corresponding shaped projections which allow the tubular key containing the grooves to pass into the entry way. The tubular key shank also includes a transverse annular recess spaced inwardly from the forward end of the key such that when the key is inserted to its lock operating position the key, grooves and housing projections are free of one another to allow the key to rotate within the lock. The tubular …