Patent ID: 9631576
Date: 2017-04-25
CPC Classifications: B23K,F02F,Y10T

Claim:
1. A method, comprising: providing a piston body that forms an entire upper combustion bowl surface, which is free from welds, the piston body forming a first portion of a cooling gallery, the piston body including radially inner and radially outer body mating surfaces and defining a piston axis; assembling a cooling gallery ring with the piston body, the cooling gallery ring forming a second portion of the cooling gallery, the cooling gallery ring including a radially inner ring mating surface and a radially outer ring mating surface; forming the cooling gallery with the first and second portions by laser welding the piston body to the cooling gallery ring along a radially inner interface region, the radially inner interface region including the radially inner mating surfaces of the piston body and the cooling gallery ring; and laser welding the piston body to the cooling gallery ring along a radially outer interface region, the radially outer interface region including the radially outer mating surfaces of the piston body and cooling gallery ring; wherein, at the radially inner interface region, the piston body includes a body step portion formed on the piston body being axially offset to and extending radially from the radially inner body mating surface, the body step portion comprising a laterally extending surface that faces the cooling gallery ring, and the body step portion forming a part of the cooling gallery; and wherein, at the radially outer interface region, the cooling gallery ring includes a cooling gallery step portion being radially offset to and axially extending from the radially outer ring mating surface, a vertically extending surface formed on the cooling gallery step portion that faces the piston body, and the cooling gallery step portion forms a part of the cooling gallery.