Abstract: A positioning joint for a folding ladeer including a pair of first joint members each of which having an axial hole and a pair of locking holes, a second joint member having an axial hole and several pairs of positioning holes, a button mechanism having an axial shaft for combining a locking member and a coil spring being placed around the shaft, and a locking member having a pair of locking bars. The two joint members are relatively pivotable about a bushing passing through the axial holes thereof and are lockable in a series of predetermined angular positions by engaging the locking bars into the locking holes and positioning holes by means of the button mechanism and locking member.

Abstract: A folding ladder comprising a plurality of hingedly intermounted sections having channel-shaped side members, ladder rungs being shiftedly connected to a first of the side members and being pivotally connected to a second of the side members, such that the rungs slide upon collapse of the side members together after a folding of the sections into a compact unit for carriage and storage.

Abstract: A positioning joint for a folding ladder comprising a first joint member having a locking device, and a second joint member having a relatively fitted guide-disc plate. The two joint members are relatively pivotable about a common axis and are lockable in a series of predetermined angular positions by engaging the locking device provided on the first joint member in notches formed at the peripheral edge of the other member, under the control of the guide-disc plate.