Abstract: Pre-shaped wrought-iron rods are placed one beside another in a lattice array, in which node-forming portions of adjacent rods are disclosed close to each other at a plurality of node positions. All node-forming portions at each of said node positions are inserted into a U-shaped strip metal element having an inwardly protruding longitudinal rib. Each of said strip metal elements is joined to said node-forming portions inserted therein by a projection welding operation in which said rib is used as a projection. Each of said strip metal elements is subsequently closed to form a closed clip embracing said node-forming portions joined thereto.

Abstract: In a shutter construction typically installed on the outside of a window and including one or more panel assemblies mounted within an outer frame for horizontal sliding movement into and out of a shutter box, each of the panel assemblies is composed of a supporting frame and a series of aligned elementary panels closely fitted in the supporting frame. The supporting frame consists of top and bottom rails and a pair of stiles, and the stiles are formed wth a tongue and a pair of clamping jaws, respectively, projecting toward each other. Each elementary panel also has a tongue and a pair of clamping jaws along its respective lateral edges which are exactly identical with the tongue and jaws of the stiles. The elementary panels are connected to each other and to the stiles solely by the clamping engagement of the tongues by the respective pairs of jaws.