Operating modular conveyor belts with migrating hinge pins

In a modular conveyor belt of the type comprising a series of rows of side-by-side belt modules extending from a first end to a second end in the direction of belt travel and from a top surface to a bottom surface through the thickness of the modules, with a first set of hinge eyes along the first end and a second set of hinge eyes along the second end, the rows being connected end to end with the first set of hinge eyes of a row interleaved with the second set of hinge eyes of an adjacent row by a hinge pin extending through the interleaved hinge eyes to form a hinge between adjacent rows, the improvement comprising:

• a protrusion extending from a first side of a first belt module in a belt row;
• and
• a receptacle formed by discontinuous wall structure at the confronting second side of a second module in the belt row,
• wherein the discontinuous wall structure defines a gap in the wall structure opening toward at least one of the top surface and the bottom surface of the second module to receive the protrusion into the receptacle through the gap from a direction generally perpendicular to the top and bottom surfaces of the modules.