Method for the production of a multi-part piston for an internal combustion engine

Abstract

A multi-part piston for an internal combustion engine has an upper piston part having a piston crown, and a lower piston part. The lower piston part has pin boss supports and pin bosses connected with them and the upper piston part and the lower piston part each have an inner and an outer support element, which elements delimit an outer circumferential cooling channel. The inner support elements delimit a cavity that is open toward the pin bosses. The cavity has a separate cooling oil collector that has at least one cooling oil opening. The piston is produced by manufacturing the upper piston part and lower piston part, inserting the cooling oil collector into the upper piston part or lower piston part, and joining the upper and lower piston parts together by friction welding.

1 . A method for the production of a multi-part piston for an internal combustion engine, comprising the following steps:
 producing an upper piston part having a piston crown as well as an inner and an outer support element;   producing a lower piston part having pin boss supports and pin bosses connected with them, as well as having an inner and an outer support element;   inserting a separate cooling oil collector, having at least one cooling oil opening, into the upper piston part or the lower piston part,   connecting the upper piston part and the lower piston part so that the inner and outer support elements delimit an outer circumferential cooling channel and a cavity that is open toward the pin bosses and provided with the cooling oil collector.   
     
     
         2 . The method according to  claim 1 , wherein the cooling oil collector is inserted into a region of the inner support element of the upper piston part, or into a region of the inner support element of the lower piston part. 
     
     
         3 . The method according to  claim 1 , wherein the inner support elements of the upper piston part and the lower piston part are connected with one another by means of a friction welding method that produces friction weld beads, and wherein the cooling oil collector is held between the friction weld beads and pin boss supports. 
     
     
         4 . The method according to  claim 1 , wherein the inner support elements of the upper piston part and the lower piston part are connected with one another by means of a friction welding method that produces friction weld beads, and wherein the cooling oil collector is held between the friction weld beads and an underside of the piston crown. 
     
     
         5 . The method according to  claim 1 , wherein the cooling oil collector is held in the upper piston part or the lower piston part, under spring bias, before upper piston part and lower piston part are connected.