US Patent 8388291 Mat lock pin

A mat lock pin for releasably holding together overlapping mats has an outer body and a rotor rotatably held within the outer body. The outer body is sized and shaped so as to snugly fit within aligned holes in overlapping mats, and is shaped so as to be non-rotational within the holes. The rotor has a central stem and a foot at each end. When the mat lock pin is in place extending through holes in overlapping mats, the rotor feet are at the outermost surfaces of the mats. Rotation of the rotor brings angled surfaces on the rotor feet to bear against the outermost mat surfaces, generating an axial force forcing the mats together. The axial forces forcing the mats together are carried by the rotor, permitting the outer body to be made of relatively low strength, and low cost, material.