Coupling assembly for joining two profiled rails

Claim 1

A coupling assembly comprising: a multi-walled first elongated profiled hollow rail having a longitudinal axis, an inner space running along said axis and an opening into the inner space of said rail, said opening extending essentially over the full length of said first rail and giving access to said inner space; a clamping element having a bearing surface and being constructed of a size and shape to allow passage thereof across said opening, said clamping element being formed with a threaded hole; means mounting said clamping element in said inner space for non-rotational but translational movement relative to said axis; means defining a fixed clamping surface in said inner space, said clamping surface and said bearing surface defining therebetween a clamping gap; said first profiled rail having a wall formed with a hole therethrough facing said threaded hole of said clamping member; a screw extending freely through said wall hole and screwed into said threaded hole of said clamping member, constructed so that rotation of said screw causes said translational movement of said clamping member and variation in the width of said clamping gap; and a second profiled rail having a leg inserted into said clamping gap, whereby rotation of said clamping screw in one direction produces a clamping pressure on said leg to secure said profiled rails together and rotation of said screw in reverse direction loosens said pressure and frees said profiled rails from one another so as to allow relative spatial adjustment of said rails, said second profiled rail having a longitudinal axis and said leg having a slot which extends into said leg from a free longitudinal edge of said leg substantially perpendicularly to the longitudinal axis of said second rail, and wherein said screw extends through said slot.