Patent ID: 8171651
Filing Date: 2012-05-08
Classification: G01B

Abstract:
1. A frame squareness testing instrument comprising a pair of arms of equal length, wherein each of said arms has opposite ends for contacting inner sides of a frame structure; and wherein said arms are pivotally interconnected at a pivot point at the centers of said arms and equi-distant from said opposite ends; wherein said pivot point is fixed and untranslatable along the axis of said arms; and wherein each of said arm ends is shaped such that, irrespective of the relative pivotal positioning of said arms, said pair of arms fit squarely into a corresponding rectangular frame with each of said arm ends in contact with adjoining inner sides of a respective corner of said corresponding rectangular frame so that there are eight points of contact between said pair of arms and said corresponding frame, whereby said pair of arms are positionable inside a structure and pivotable apart to try and bring said arm ends in contact with inner sides of said structure to test at least one of the squareness and parallelism thereof.