Abstract: A piston for an internal combustion engine which includes a crown having spiral features designed to increase swirl of combustion gases in a cylinder of the engine is provided. The spiral features can be located in a combustion surface or in a combustion bowl of the crown. The increased swirl of the combustion gases is expected to improve mixing of the air and fuel injected into the cylinder, and thus cause the fuel to burn more completely, achieve better efficiency out of the injected fuel, and reduce unburned hydrocarbons in the exhaust gas.

Abstract: A piston for an internal combustion engine which includes a crown having spiral features designed to increase swirl of combustion gases in a cylinder of the engine is provided. The spiral features can be located in a combustion surface or in a combustion bowl of the crown. The increased swirl of the combustion gases is expected to improve mixing of the air and fuel injected into the cylinder, and thus cause the fuel to burn more completely, achieve better efficiency out of the injected fuel, and reduce unburned hydrocarbons in the exhaust gas.

Abstract: A piston for an internal combustion engine which is coated for enhanced oxidation protection and/or erosion protection is provided. The piston includes a body formed of an iron-based material. The iron-based material is coated with a superalloy and manganese phosphate. The superalloy is preferably NiCrAlY, NiCrAl, NiCr, CoCrAly, and/or CoNiCrAlY. The manganese phosphate can be disposed on the superalloy, but not between the superalloy and the iron-based material. The superalloy preferably has a thickness of 0.1 to 2.0 mm, a porosity of 1% to less than 5%, and a surface roughness of less than 5 microns Ra. Another component for an internal combustion engine which is coated with the superalloy and the manganese phosphate is also provided.

Abstract: A piston for an internal combustion engine which is coated for enhanced oxidation protection and/or erosion protection is provided. The piston includes a body formed of an iron-based material. The iron-based material is coated with a superalloy and manganese phosphate. The superalloy is preferably NiCrAlY, NiCrAl, NiCr, CoCrAly, and/or CoNiCrAlY. The manganese phosphate can be disposed on the superalloy, but not between the superalloy and the iron-based material. The superalloy preferably has a thickness of 0.1 to 2.0 mm, a porosity of 1% to less than 5%, and a surface roughness of less than 5 microns Ra. Another component for an internal combustion engine which is coated with the superalloy and the manganese phosphate is also provided.

Abstract: A piston capable of operating at a high temperature and consequently contributing to a high in-cylinder temperature, as well as reducing engine oil temperature, when used in an internal combustion engine, is provided. The piston includes an upper portion and a lower portion welded together to present a cooling gallery therebetween. The cooling gallery extends circumferentially around a center axis of the piston and is spaced the center axis. A partition is located in the cooing gallery and extends from one inner surface to another inner surface of the cooling gallery. The partition extends circumferentially around the center axis, and divides the cooling gallery into at least a first gallery portion and a second gallery portion. The partition can be formed as one piece with the upper portion or the lower portion. Alternatively, the partition can be formed as a separate piece from the upper portion and the lower portion.

Abstract: A galleryless piston for an internal combustion engine is provided. The piston has a monolithic piston body including an upper wall forming an upper combustion surface with first and second portions. The first portion extends annularly along an outer periphery of the upper wall and the second portion includes a combustion bowl. The first portion can also include valve pockets formed therein to reduce weight. The upper wall has an undercrown surface directly opposite the second portion of the upper combustion surface. To enhance cooling, a center portion of the undercrown surface is concave, such that oil is channeled during reciprocation of the piston from one side to the opposite side of the piston. The concave center portion is axially offset from the surrounding area of the undercrown surface.

Abstract: A steel piston with a bushing applied to pin bore surfaces by laser cladding or laser additive manufacturing is provided. The bushing is formed of metal, such as bronze, and metallurgically bonded to the steel of the piston. Thus, the bushing cannot fail by rotating relative to pin bore surfaces. The bushing has a porosity ranging from 0.05% to 5%, based on the total volume of the bushing, and a thickness ranging from 0.07 mm to 6 mm. Since the metal is applied directly to the steel by laser cladding or laser additive manufacturing, the overall size of the piston is reduced, compared to typical pistons with a separate steel backed bushing, and the possibility of bushing rotation is avoided. The bushing also provides scuffing resistance and increased unit load capacity of the pin bore.

Abstract: A galleryless steel piston for an internal combustion engine is provided. The piston has a monolithic piston body including an upper wall forming an upper combustion surface with first and second portions. The first portion extends annularly along an outer periphery of the upper wall and the second portion defines a combustion bowl. The piston further includes undercrown surface located directly opposite the combustion bowl with an exposed 2-dimensional surface area allowing for contact of cooling oil. The exposed 2-dimensional surface area ranges from 25 to 60 percent of a cross-sectional area defined by a maximum outer diameter of the piston body. To further enhance cooling, a portion of the undercrown surface is concave or convex, such that oil is channeled during reciprocation of the piston from one side to the opposite side of the piston.

Abstract: A vehicle internal combustion piston and method of construction thereof are provided. The piston includes piston body extending along a central longitudinal axis, having an upper combustion wall forming an upper combustion surface and an undercrown surface opposite the upper combustion surface. An annular ring belt region depends from the upper combustion surface, a pair of skirt panels depend from the ring belt region, and a pair of pin bosses depend from the undercrown surface to provide laterally spaced pin bores aligned along a pin bore axis for receipt of a wrist pin. The undercrown surface forms a central undercrown region, and a portion of either an open outer cooling gallery, a sealed outer cooling gallery, or an outer galleryless region, wherein an insulating coating including a thermoset resin, such as a phenolic or epoxy resin, with additives is applied to at least one of the portions of the undercrown surface.

Abstract: A piston for an internal combustion engine and method of construction is provided. The piston has a robust, lightweight monolithic piston body including an upper wall forming a combustion bowl depending radially inwardly from an annular, uppermost combustion surface. An undercrown surface is formed on an underside of the combustion bowl, with at least a portion of the undercrown surface being bounded by diametrically opposite skirt portions, pin bosses and strut portions connecting the skirt portions to the pin bosses. The bounded undercrown surface has an openly exposed surface area, as viewed looking along a central longitudinal axis along which the piston reciprocates, providing an expansive area against which oil being splashed or sprayed can come into direct contact with to enhance cooling the piston while in use. Through channels extending over upper regions of the pin bosses can be provided to further reduce weight and facilitate cooling.

Abstract: A piston assembly, piston therefor and methods of construction are provided. The assembly includes a piston head and connecting rod operably coupled thereto via a wrist pin. The piston head has an upper crown with a combustion bowl and an undercrown surface. The lower crown includes axially aligned pin bores receiving the wrist pin. An upper wall of the lower crown has an oil inlet, an oil outlet and a concave, saddle bearing surface that bears against the wrist pin. A toroid-shaped outer cooling gallery is formed between wall portions of the upper and lower crowns, wherein the outer cooling gallery surrounds an inner cooling gallery. The connecting rod is fixed to the wrist pin for conjoint oscillation. The connecting rod has an oil passage in fluid communication with a through hole in the wrist pin to allow oil to flow therethrough into the inner cooling gallery via the oil inlet.

Abstract: A pin including recesses extending longitudinally between opposite ends, and a piston assembly including the pin, for a two-stroke engine, is provided. The recesses preferably have a radius of curvature less than a radius of curvature of the remaining outer surface of the pin. The pin is rotationally fixed relative to the connecting rod. As the connecting rod swings back and forth during operation, some of the recesses rotate beyond the load bearing region of the pin joint where oil is located, allowing oil to fill the recesses. As the pin swings back, these recesses carrying the oil enter the load bearing region of the pin joint, transferring the oil with them. Preferably, at least one of the recesses aligns with an oil opening in the pin, which aligns with an oil hole in the connecting rod, to receive and distribute oil along the full length of the pin.

Abstract: A galleryless piston having a reduced temperature during operation in an engine is provided. The piston includes an upper wall with an exposed undercrown surface. A ring belt and pin bosses depend from the upper wall, and a pair of skirt panels depend from the ring belt and are coupled to the pin bosses by struts. The piston includes an inner undercrown region and outer pockets extending along the undercrown surface. The inner undercrown region is surrounded by the skirt panels, the struts, and the pin bosses. Each outer pocket is surrounded by one of the pin bosses, a portion of the ring belt, and the struts adjacent the one pin boss. A plurality of holes extend through the pin bosses and/or the struts from the inner undercrown region to one of the outer pockets to convey cooling oil from the inner undercrown region to the outer pockets.

Abstract: A galleryless piston and method of construction provide a piston body forged from a single piece of material having an upper combustion surface extending around a longitudinal center axis along which the piston reciprocates for exposure to a combustion chamber of an internal combustion engine. The upper combustion surface has an asymmetric geometry relative to a center plane extending along the central longitudinal axis in generally perpendicular relation to a pin bore axis.

Abstract: A piston assembly for a two-stroke internal combustion engine includes an upper part joined to a lower part by hybrid induction welding. The upper part includes an upper and lower walls radially spacing inner and outer walls to present an outer cooling gallery therebetween. The lower wall includes first portions extending radially inwardly from the outer wall to the inner wall above the skirt sections and second portions extending radially inwardly from the outer wall to the inner wall above the pin bosses. The first portions extend oblique to the center axis and undulate between the inner and outer walls to reduce the stiffness of the skirt sections. The second portions of the lower wall extend perpendicular to the center axis. Skirt sections of the piston include a lower portion with a greater radial thickness and containing ring grooves.

Abstract: A piston galleryless piston capable achieving improved thermal efficiency, fuel consumption, and engine performance is provided. The piston includes an undercrown surface exposed from an underside of the piston, a ring belt, pin bosses, and a pair of skirt panels coupled to the pin bosses by struts. The piston includes an inner undercrown region extending along the undercrown surface and surrounded by the skirt panels, struts, and pin bosses. The piston also includes a pair of outer pockets extending along the undercrown surface and each being surrounded by a portion of the ring belt, one of the pin bosses, and the struts coupling the one pin boss to the skirt panels. Each pin boss includes an opening extending from the inner undercrown region to one of the outer pockets for conveying cooling oil. The opening is located between a pin bore of the associated pin boss and the undercrown surface.

Abstract: A galleryless piston having a reduced weight and a reduced operating temperature is provided. The piston includes an undercrown surface exposed from an underside of the piston, a ring belt, pin bosses each presenting a pin bore, and skirt panels depending from the ring belt and coupled to the pin bosses by strut. The piston further includes an inner undercrown region extending along the undercrown surface and surrounded by the skirt panels, the struts, and the pin bosses. The piston also includes outer pockets each extending along the undercrown surface and each surrounded by a portion of the ring belt, one of the pin bosses, and the struts coupling the one pin boss to the skirt panels. Cutouts are located in the pin bosses above the pin bores to increase the area of the undercrown surface and thus allow cooling oil to remove more heat from the undercrown surface.

Abstract: A piston assembly, piston therefor and methods of construction are provided. The assembly includes a piston head and connecting rod operably coupled thereto via a wrist pin. The piston head has an upper crown with a combustion bowl and an undercrown surface. The lower crown includes axially aligned pin bores receiving the wrist pin. An upper wall of the lower crown has an oil inlet, an oil outlet and a concave, saddle bearing surface that bears against the wrist pin. A toroid-shaped outer cooling gallery is formed between wall portions of the upper and lower crowns, wherein the outer cooling gallery surrounds an inner cooling gallery. The connecting rod is fixed to the wrist pin for conjoint oscillation. The connecting rod has an oil passage in fluid communication with a through hole in the wrist pin to allow oil to flow therethrough into the inner cooling gallery via the oil inlet.

Abstract: A galleryless piston for an internal combustion engine and method of construction thereof are provided. The piston has a monolithic piston body extending along a central longitudinal axis. The piston body has an upper wall forming an upper combustion surface with first and second portions, with the first portion extending annularly along an outer periphery of the upper wall and the second portion forming a combustion bowl. The upper wall has an undercrown surface on an underside of the combustion bowl directly opposite the second portion of the upper combustion surface. The undercrown surface has an openly exposed surface area, as viewed looking along the central longitudinal axis, thereby providing an expansive area against which oil being splashed or sprayed can freely contact to cool the piston.

Abstract: A piston assembly, piston therefor and methods of construction are provided. The assembly includes a piston head and connecting rod operably coupled thereto via a wrist pin. The piston head has an upper crown with a combustion bowl and an undercrown surface. The lower crown includes axially aligned pin bores receiving the wrist pin. An upper wall of the lower crown has an oil inlet, an oil outlet and a concave, saddle bearing surface that bears against the wrist pin. A toroid-shaped outer cooling gallery is formed between wall portions of the upper and lower crowns, wherein the outer cooling gallery surrounds an inner cooling gallery. The connecting rod is fixed to the wrist pin for conjoint oscillation. The connecting rod has an oil passage in fluid communication with a through hole in the wrist pin to allow oil to flow therethrough into the inner cooling gallery via the oil inlet.