Patent ID: 8341806

Claim:
A hinge for a folding step stool comprising: a top rail; an upper hinge having a c shape that surrounds the top rail; a front rail; a rear rail; a lower hinge having a c shape that surrounds the front rail, the upper hinge comprises two upper hinge plates that surround the rear rail and the lower hinge comprises two lower hinge plates that surround the upper hinge plates and the rear rail; a bushing that extends through the upper and lower hinges and rear rail and holds the upper and lower hinges and rear rail together and about which the upper and lower hinges and rear rail rotate relative to each other and the top rail, front rail and rear rail are held by the upper hinge and lower hinge essentially parallel in a folded state and the top rail is held in alignment with the front rail by the upper hinge and the rear rail is held in an acute angle with the front rail by the lower hinge in an unfolded state; and a bar that has a shank and a projection, and the bushing has a center hole in which the shank is disposed and rotates freely, and the projection fits into the lower hinge which constrains the bar to move with the lower hinge in the folded or unfolded state, and the projection fits into the upper hinge and either engages or disengages the upper hinge when the bar is slid axially in the bushing.