Elements for interconnection of ends of profiles at corners in frames, panel points and the like

An unitary element for interconnecting the ends of frame sections at corners in frames, panel points and the like, comprising four legs arranged in a cross configuration, one pair of adjacent legs at an angle to each other and each having in common an inner and an outer angle wall said angle walls being opposed to each other and defining an intermediate space therebetween and inclined end walls connected to the corresponding ends of the angle walls in each leg, the inner angle wall which borders the interior space of the angle defined by the pair of legs forming an inner apex point, and the other pair of adjacent legs having the same arrangement of inner, outer, and inclined end walls as the one pair, the arrangements of both pairs being joined back-to-back along a common axis of their respective outer walls to form the cross configuration, said element further comprising means for drawing the inner apex points of the respective arrangements toward each other so as to impart in each of the four legs a displacement of the walls relative to each other which, in cooperation with the inclined end walls of the respective legs, causes contemporary and substantially equal force to be applied so as to expand the legs in the ends of the respective frame sections to fasten the frame sections together.