Method of manufacturing a vertical scaffolding element, and element thus obtained

Abstract

A vertical scaffolding element consists of a tubular portion provided with a number n of radially projecting sockets, distributed peripherally in a star arrangement. The element is designed for the attachment of one end of a horizontal crosspiece of the scaffolding. The sockets are defined by a metal strip folded in order to form a star-shaped part closed on itself having protuberances forming the sockets alternating with re-entrant regions bearing against the tubular portion. The upper and lower edges of the re-entrant regions in contact with the tubular portion are welded thereto by continuous or discontinuous annular weld beads.

1 . A method of manufacturing a vertical scaffolding element having a tubular portion to which is welded a star-shaped part defining a number n of radially projecting sockets, said sockets being distributed peripherally in a star arrangement and intended for the attachment to one end of a horizontal crosspiece of the scaffolding, said method comprising the steps of: 
 a) stamping a plane metal strip of a predetermined length at n regularly spaced locations so as to form a stamped strip with n recesses, each said recess being approximately a dihedral arrangement with a rounded ridge transverse to the length of the strip,    b) folding said stamped strip at joins joining ends of lateral faces of the dihedral arrangements with intermediate plane regions of the strip so as to bring closer to each other the lateral faces of two adjacent recesses which are located on each side of the plane regions of the strip and so as to position the rounded ridges of the recesses on an axisymmetric cylindrical outline having substantially a same diameter as an external surface of the tubular portion in order to close said stamped strip on itself with free ends of said stamped strip being abutted whereby a star-shaped member is formed,    c) positioning said star-shaped member on said tubular portion with the rounded ridges of the dihedral arrangements formed by the recesses resting against the external surface of the tubular portion, and    d) welding said star-shaped member to said tubular portion,    wherein the free abutted ends of the stamped strip are located substantially in a region of the star-shaped member which bears against the tubular portion after the star-shaped member has been mounted thereon, and    wherein after said folding step b) and before said positioning step c), both free abutted ends of the stamped strip are welded to each other so as to obtain the star-shaped member which is integral, and    wherein during said welding step d), said integral star-shaped member is secured to the tubular portion only by discontinuous circular welds made on upper and lower edges of the rounded ridges resting on the tubular portion.    
   
   
       2 . The method according to  claim 1 , wherein the recesses are formed as dihedral arrangements which are open over an angle of 2π/n.  
   
   
       3 . The method according to  claim 2 , wherein the stamped strip is folded so as to bring the lateral faces of two adjacent recesses into a substantially parallel mutual position.  
   
   
       4 . The method according to  claim 1 , wherein the stamped strip is folded so as to bring the lateral faces of two adjacent recesses into a substantially parallel mutual position.  
   
   
       5 . The method according to  claim 1 , wherein the number of recesses is four and wherein an angle α of opening of the dihedral arrangement formed by the recesses is about 90°, whereby the vertical scaffolding element consists of a tubular portion equipped with four said sockets placed substantially in a cross arrangement.  
   
   
       6 . The method according to  claim 1 , wherein the rounded ridges are formed with a concavity thereof turned outwards, so that the rounded ridges are applied tightly against the tubular portion.  
   
   
       7 . A vertical scaffolding element comprising four sockets defined by a metal strip folded in a cross arrangement with orthogonal branches and welded to a tubular portion, characterized in that said vertical scaffolding element is manufactured by implementing the method according to  claim 1.