Process for transmission laser welding of plastic parts

Abstract

A process for transmission laser welding of a first plastic part and a second plastic part that can be at least partially received in the first plastic part is proposed. The second plastic part is introduced into the first plastic part, to which it is connected by means of an interference fit connection, whereby at least one contact zone between the second plastic part and the first plastic part is formed as a result of this interference fit. A laser beam is directed to impinge on the second plastic part, through the first plastic part, along the at least one contact zone to form a weld.

1 . A process for welding a plastic housing of an electrical device, comprising the steps of: 
 providing an outer housing part comprising a cylindrical shell closed at one end; providing an inner housing part comprising a support element, in which electrical components are accommodated, and a cylindrical element having an outer diameter which is inferior to the inner diameter of said cylindrical shell of said outer housing part, said cylindrical element further comprising a peripheral rib having an outer diameter which is superior to the inner diameter of said cylindrical shell of said outer housing part;    introducing said inner housing part into said outer housing part in such a way that said support element with said electrical components are enclosed by the two housing parts, and that said peripheral, annular rib is inside the outer housing part, about the open end thereof, whereby an annular contact zone is formed between said rib and said cylindrical shell of said outer housing part; and    directing a laser beam to impinge on said peripheral, annular rib, through said cylindrical shell of said outer housing part, along said at least one contact zone to form a weld; wherein said laser beam should preferably be perpendicular to said outer housing at the point of incidence.    
     
     
         2 . A process for welding a plastic housing of an electrical device of  claim 1 , wherein said laser beam has a wavelength ranging from 0.50 μm to 10.90 μm, preferably between 800 to 1100 nm.  
     
     
         3 . A process for welding a plastic housing of an electrical device of  claim 1 , wherein said inner housing part and said outer housing part comprises of polyolefines, polyamides, polyformaldehyd, PMMA, PBT, PET or a combination comprising at least one of the foregoing.  
     
     
         4 . A process for welding a plastic housing of an electrical device of  claim 3 , wherein said inner housing part or said outer housing part or both comprises glass fibers, glass globes or a combination of at least one of the foregoing.