Multi-layer composite-wall panel or case structure

A method for producing a composite-wall case structure comprising two assembled composite wall panels, each comprising at least two shaped walls having regions in which confronting surfaces thereof are in adjoining relation to each other and interconnected by bonding and spot-welding and regions in which hollow bodies are formed between said confronting surfaces for imparting a required rigidity to the panel, one of said walls constituting an outer shell and the other wall constituting a rolling bearing-carrying wall located inside said case structure, said walls defining apertures for the passage of shafts, said method comprising providing at least two shaped walls each having a main surface, assembling said walls on their main surfaces, with interposition of a layer of a bonding material so as to constitute a laminated structure, and subjecting said laminated structure to a spot-welding step and thereafter to a final treatment for activating said bonding material.