Investment-cast piston crown cap with encapsulated non-metallic insulating core
AssigneeAe PLC
InventorDavid F. Fletcher-Jones
Life of this patent
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Abstract
Pistons for internal combustion engines, particularly compression ignition engines. The pistons have insulating crowns and include a crown having a cap thereon, extending over the crown surface area, the crown cap being composed of an iron-based or a nickel-based alloy and having on the underside thereof ribs which are encast into an aluminium alloy which forms the piston body. The crown cap further includes a ceramic insert encapsulated therein. The ceramic insert may also be leached out by chemical means to leave a void in the cap.
Claims14
A piston for an internal combustion engine, the piston comprising a crown portion and a body portion, the crown portion having a cap extending over the surface area thereof, said crown cap being an investment casting of an iron-based or a nickel-based alloy, said investment casting also having encasted and encapsulated therein a non-metallic insulating core.
A method of making a piston having a crown portion and a skirt portion for an internal combustion engine, the method comprising the steps of making an iron-based or nickel-based alloy crown cap having therein an encasted and encapsulated ceramic core by an investment casting technique, placing the crown cap into a casting die and casting an aluminium alloy onto said crown cap to form said skirt portion.
Dependencies are inferred from the claim text.