GB1138890A - Locking hinge - Google Patents

Abstract

1,138,890. Self-locking hinge. HARSCOCORP. 21 Dec., 1966 [2 Feb., 1966], No. 57298/66. Heading E2F. An automatically locking hinge for locking two elongated members in an extended position comprises two housing parts hinged together end to end by a laterally offset hinge, one part having a longitudinal recess with end and side openings presenting its end opening to a like recess in the other part, a rod or keeper being mounted transversely across one recess and a spring biased latch, rockably pivoted in the other recess, extending into the first recess to bear yieldingly upon and lock into engagement with the keeper. Two housing parts, 12 and 13, telescoped into 'the ends 10 and 11 of elongated structral members (e.g. scaffold poles) and secured by deformations 14, have laterally projecting hinge lugs, a single lug 15 on part 12 being disposed between two spaced lugs 16 on part 13, which are secured together by a pivot pin 17. Housing 12 has a recess 20, opening laterally and through the end face 18, wherein is transversely mounted a keeper or rod 21. Housing 12 carries a latch 23 pivotably mounted at 24 in a like recess 22, the latch having a stud 32 at one end, a boss 27 with a first bearing face 28 positioned to ride on the inner face 29 of the recess, and an outer end forming a second bearing face 33 intersecting a locking face 34 at a shoulder 35. A spring 31 is positioned in a cavity 30, and engages with the stud 32 to bias the latch towards locking engagement with the keeper. When the parts are as shown in Fig. 5, movement towards the extended position of Fig. 3 'brings the second bearing face 33 into engagement with the keeper, which latter, when it passes the shoulder 35, allows the latch to lock into engagement under pressure from the spring, with the first bearing face 28 of the boss bearing on the surface 29 to stabilise the joint and prevent wobbling. By manual pressure on part 26 of the latch, the latter is disengaged from the keeper to unlock the joint.