Device for assembling sectional for instance metallic bars

Device for endwise assembling a first sectional bar onto a second sectional bar extending at right angles thereto and having at least one flat face formed with a half-closed groove terminating at its open portion, at said flat face, in lips which restrict the size of the opening, said device comprising a rod portion and a tubular element which receives the rod portion, the latter being provided with an elongated head portion with parallel sides adapted to be inserted into the groove of the second sectional bar at any point thereof and then locked with the latter through a quarter turn rotation, said rod portion being provided with a high pitch helical groove extending over a quarter turn thereabout and terminating in a cup-like recess, a set screw screwed into a threaded hole in said tubular element and engaging said high pitch helical groove, said set screw projecting into the cup-like recess for holding said rod portion againsts motion in the tight clamping position, the position and shape of said cup-like recess ensuring that the lips of said groove are pressed against said head portion and the end of said first sectional bar, said element being positioned within the end of a hollow core of said first sectional bar, one face of this core being formed with an elongated slot the length of which is at least equal to the sum of the depth of said groove of said second sectional bar and of the length of said helical groove of said rod portion, said set screw extending through said slot whereby through displacement of said screw in said slot, said head portion may be fully retracted inside of said hollow core of said first sectional bar, said element further comprising means preventing its relative rotation with respect to at least one of said sectional bars.