Scaffold tube coupler

Claim 1

A coupler for connecting two round scaffold tubes together and of the kind, which comprises a central body formed as a metal drop forging having on each of two opposite sides thereof a tube receiving seating, the seatings being so relatively disposed that the two tubes are connected together in mutually perpendicular relationship, the body at each of two opposite sides thereof adjacent each seating being provided with a pair of hinge lugs formed integrally with the central body during the drop forging operation, so that each of the four lugs embody substantially the same mass of metal, one of the two lugs of each pair having hinged thereto one end of one of two tube securing jaws each formed to provide a tube receiving recess, and the other of the two lugs of each pair having hinged thereto a clamping bolt arranged for detachable clamping engagement with the other and free end of one of the two jaws, each clamping bolt being adapted to hinge under its own weight towards its associated jaw when the latter is at a horizontal level which is below that of the bolt, means being provided for limiting such hinging movement of each clamping bolt, the two lugs of each pair being disposed on diametrically opposite sides of their respective seatings, with the one end of each jaw connected to the jaw hinging lug being forked, with each jaw hinging lug extending between the two arms of the fork and being engageable at its free end with the jaw at the base of the fork so as to provide a stop to limit the opening pivotal movement of the jaw, characterised in that the stop forming free end of each jaw hinging lug is chamfered at a position and to an extent such as to allow the associated jaw to swing outwardly away from the associated body seating through an angle sufficiently greater than 90* as to permit of the horizontal tube being engaged with the said open jaw by displacing the tube transversely of its length without manually grasping and manipulating the adjacent clamping bolt in so doing, said angular opening movement of each jaw being so limited by the engagement between the associated stop forming lug and the open jaw, that the hoRizontal tube is still received in and supported by the recess of said open jaw, and each jaw hinging lug adjacent its junction with the central body having its cross section increased in a direction perpendicular to the axis of the jaw hinge pin to provide a rectilinear side directed away from the central body and thus strengthen it against bending by a mass of metal substantially equal to that saved by the said chamfering, and so as to maintain substantially the same mass of metal in each of the four lugs of the body.