Patent ID: 7805850

Claim:
A modular edge reference tool comprising: a first segment of the edge reference tool defining a longitudinal axis and a reference edge and having a extending end; a second segment of the edge reference tool defining a longitudinal axis and reference edge and having a receptacle end; and a coupling mechanism including a first component mounted within the extending end of the first segment and a second component mounted within the receptacle end of the second segment, wherein the coupling mechanism couples the extending end of the first segment to the receptacle end of the second segment; wherein the first component of the coupling mechanism includes a shaft substantially collinear to and positioned along the longitudinal axis of the first segment, wherein the shaft includes an external geometry that extends from the extending end in a first position, retracts to be flush with the extending end in a second position, and retracts to be in a position in between the first and second position when engaged to the second component in a third position, and a spring that provides a bias on the shaft to be flush with the extending end in the second and third positions; wherein the second component of the coupling mechanism includes a hole substantially collinear to the longitudinal axis of the second segment, wherein the hole includes an entrance geometry that allows the hole to receive the shaft of the first component in the first position when the second segment is offset 90 degrees along the longitudinal axis from the first segment, and wherein the hole includes internal geometry that subsequently engages the external geometry of the shaft and moves the shaft deeper into the hole upon a 90 degree rotation of the second segment, upon which the spring provides a force against the movement, wherein the external geometry of the shaft, the internal geometry of the hole, and the spring force cooperate to align the first and second segments, and wherein retraction of the shaft to the third position provides further spring force to couple the first and second segments.