Abstract: A connection between a circular cylindrical tube and a plate or sleeve includes a housing extending along an axis from an inlet opening in a surface of the plate or sleeve and a circular cylindrical tube having an end fittable in the housing. The housing includes a first cylindrical truncated cone extending to the inlet opening and having a vertex angle .beta. with respect to the axis of between 5.degree. and 20.degree., and a second oval truncated cone coaxial with the first cone and connected thereto. The second cone has generatrices forming an angle .alpha. of between 0.5.degree. and 5.degree. with respect to the axis.

Abstract: Device for assembly of profiles by a groove, tongue fitting, with locking by key, which avoids the risks of tongue and key sliding along groove. The device consists of making one of the male elements, tongue or key, longer than the other, in the direction of the generatrices of groove, and making one of the side surfaces of the longer element concave along the generatrices of groove. The invention allows realization of trellis constructions having oblique bars.

Abstract: The present invention provides an improved method for hydro-mechanical stamping wherein hollow products are formed from flat blanks by the cooperation of a punch and a liquid female tool. The present method particularly provides for submerging in the liquid the blank which is to be stamped, the level of the liquid being also maintained above the usual stamping ring. The invention further provides apparatus which acts to center the blank relative to the stamping ring, the present apparatus comprising an additional ring rigidly connected to the stamping ring and having radial apertures therein which form portions of circuitous liquid paths through which liquid flows on stamping, the paths acting to prevent localized rupture during stamping. The present method and apparatus find particular application to the high-speed manufacture of hollow, thin-walled articles of non-cylindrical shape.

Abstract: A process for producing thermoformed articles from thin-walled blanks composed of aluminum or magnesium alloys, the present invention particularly provides for forming a layer of alumina or magnesia on the surfaces of the respective aluminum or magnesium blank. The alumina or magnesia layers so formed are artificially formed in order to obtain desired thicknesses, the regular layers allowing ready removal of the articles from thermoforming molds. The present process is particularly intended for the production of thin-wall packaging members and motor vehicle components.