Complex-shaped piston oil galleries with piston crowns made by cast metal or powder metal processes
AssigneeFederal-Mogul Corporation
InventorNORBERT G. SCHNEIDER
Life of this patent
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Abstract
A steel piston with an oil gallery, and process for forming a steel piston oil gallery channel, which corresponds to the complex shape of the combustion bowl in the piston crown. The piston crown is made by a cast metal or powder metal forming process. The oil gallery channel is formed to the basic shape that corresponds to the shape of the walls of the combustion bowl. Machine-turning surfaces in the oil gallery channel can be machine-finished as desired. Surfaces in the oil gallery which cannot be machined with conventional turning operations, such as recesses and protrusions into the channel, are left in the original as-formed condition.
Claims15
(canceled)
A piston comprising:
- a lower member, said lower member comprising sidewall portions and pin bores;
- an upper crown member joined to said lower member, said upper crown member having a combustion bowl on an upper side thereof and a lower surface on a lower side thereof, wherein said combustion bowl includes a plurality of protrusions spaced from one another along its outer perimeter, and said lower surface includes machined portions.
A method of manufacturing a piston, comprising the steps of:
- providing a lower member including sidewall portions and pin bores;
- providing an upper crown member having a combustion bowl on an upper side thereof and a lower surface on a lower side thereof, wherein the combustion bowl includes a plurality of protrusions spaced from one another along its outer perimeter;
- machining the lower surface of the upper crown member;
- and
- joining the upper crown member to the lower crown member.
Dependencies are inferred from the claim text.