Patent ID: 7007344
Filing Date: 2006-03-07
Classification: E05D,E05Y,E06C,Y10T

Abstract:
1. A safety unit of a hinge for a folding ladder, the hinge comprising: a first joint unit having at a predetermined position thereof a first stop shoulder; a second joint unit coupled to the first joint unit by a central shaft so that the first and second joint units pivot on the central shaft while rotating relative to each other, with a second stop shoulder being provided at a predetermined position of the second joint unit to be opposite to the first stop shoulder; a guide disc provided in the first joint unit to be operated in cooperation with the second joint unit; and a locking unit provided at a predetermined position of the first joint unit, the locking unit engaging with one of notches provided along a peripheral edge of the second joint unit so that the first and second joint units are locked at a desired angular position, the safety unit being provided between the first and second stop shoulders, and comprising: a mount part fastened to a predetermined portion of the first joint unit to be positioned under the first stop shoulder, with an inside portion of the mount part being rounded to surround a part of the first joint unit; an insert part integrally extending from an upper end of the mount part and rounded to have a same curvature as the inside portion of the mount part, the insert part being inserted into the second stop shoulder when the second joint unit rotates relative to the first joint unit; an insert blade inwardly projected from horizontal center lines of inside portions of both the mount part and the insert part, the insert blade being circumferentially inserted into an outer circumferential surface of the first joint unit; a mount hole provided at a predetermined portion of the first joint unit to be disposed under the first stop shoulder; and a mount rod provided at a predetermined position of the mount part to be fitted into the mount hole.