Pistons and piston assemblies for internal combustion engines

Patent metadata

Field	Value
Publication number	US-11959412-B2
Application number	US-202217661778-A
Country	US
Kind code	B2
Filing date	May 3, 2022
Priority date	May 4, 2021
Publication date	Apr 16, 2024
Grant date	Apr 16, 2024

Abstract

Pistons and piston assemblies for an internal combustion engine is provided. The piston assembly includes a piston coupled to a connecting rod with a piston pin. The piston pin includes a non-circular outer cross-sectional shape.

First claim

What is claimed is:

1. A piston pin for coupling a connecting rod to a piston, the piston pin comprising:
a cylindrical piston pin body including a first surface configured to be engaged to an end of the connecting rod with the piston pin body positioned within the piston to couple the connecting rod to the piston, the piston pin body extending along a longitudinal axis that is transverse to the connecting rod, the piston pin body further including an outer surface extending around the longitudinal axis from the first surface, the outer surface having a non-circular shape around the longitudinal axis from one side of the first surface to an opposite side of the first surface, the opposite sides of the first surface and the non-circular shape extending a length of the piston pin body along the longitudinal axis.

2. The piston pin of claim 1 , wherein the outer surface includes:
a first portion opposite the first surface, the first portion of the outer surface extending along an arc defined by a diameter extending through a center of the piston pin body; and
a second portion forming a non-circular shaped portion of the outer surface around the longitudinal axis that connects the first portion to the one side of the first surface.

3. The piston pin of claim 2 , wherein the outer surface includes:
a third portion opposite the second portion, the third portion forming a non-circular shaped portion of the outer surface around the longitudinal axis that connects the first portion to the opposite side of the first surface.

4. The piston pin of claim 3 , wherein each of the first portion and the first surface connects the second portion and the third portion on opposite sides of the piston pin body, and the first surface is a flat surface.

5. The piston pin of claim 3 , wherein:
the piston pin body includes a vertical axis extending through the center of the piston body;
the first portion is centered on the vertical axis;
the piston pin body includes a horizontal axis orthogonal to the longitudinal axis and the vertical axis; and
the second portion and the third portion are elliptical in shape and offset vertically from the horizontal axis by an angular orientation.

6. The piston pin of claim 1 , wherein the outer surface of the piston pin body includes:
a second surface opposite the first surface and the-non-circular shape of the outer surface forms at least one lobe located between first surface and the second surface; and
the first surface is a flat surface extending along the longitudinal axis and the flat surface includes at least one hole for receiving a fastener to engage the piston pin body to the end of the connecting rod.

7. A piston assembly for an internal combustion engine, the piston assembly comprising:
a piston that is movable along a cylinder bore of the internal combustion engine, the piston including an upper portion and a lower portion, the upper portion of the piston including a crown facing the cylinder bore; and
a piston pin extending along a longitudinal axis transversely to the piston, the piston pin being coupled to the piston below the crown, wherein the piston pin includes an outer surface extending around the longitudinal axis and a flat surface with opposite sides extending a length of the piston pin along the longitudinal axis, the outer surface having a non-circular shape from one side of the flat surface and from an opposite side of the flat surface to a first portion of the outer surface opposite the flat surface so that gaps for receiving fluid are created between the piston pin and the upper portion of the piston in response to the piston moving along the cylinder bore.

8. The piston assembly of claim 7 , further comprising a bearing cage in the piston, the piston pin being engaged to the bearing cage, and the bearing cage is coupled to the piston to form a cooling gallery below the crown.

9. The piston assembly of claim 8 , wherein the bearing cage includes a pin bore, and the piston pin is housed in the pin bore.

10. The piston assembly of claim 7 , wherein:
the piston pin includes a vertical axis that intersects the longitudinal axis and a horizontal axis orthogonal to the longitudinal axis and the vertical axis;
the first portion of the outer surface is centered on the longitudinal axis, the first portion lying on a circle having a diameter extending through the center; and
the outer surface includes a second portion and a third portion opposite the second portion, the first and second portions connecting the flat surface to the first portion on opposite sides of the vertical axis, wherein the second and third portions form lobes that project outwardly from the circle defined by the diameter, the lobes being vertically offset from the horizontal axis by an angular orientation.

11. The piston assembly of claim 9 , wherein the piston pin is configured to lift the piston off the piston bore in response to movement of the piston along the cylinder bore.

12. The piston assembly of claim 10 , wherein the connecting rod includes a passage to supply fluid to the piston pin.

13. The piston assembly of claim 7 , further comprising at least one piston cooling nozzle interface port on an underside of the piston that is configured to direct fluid toward the crown for cooling the piston.

14. The piston assembly of claim 7 , wherein upper portion of the piston includes a piston bowl in the crown of the piston, and the lower portion of the piston includes a piston skirt that extends around the piston pin.

15. The piston assembly of claim 14 , wherein the upper portion and the lower portion of the piston mate together to form a cooling gallery below the piston bowl.

16. The piston assembly of claim 15 , wherein the piston includes at least one inlet that directs fluid toward the cooling gallery to cool the piston and at least one outlet for the fluid to exit the piston.

17. A piston cooling arrangement for an internal combustion engine, the piston cooling arrangement comprising:
a piston configured to reciprocally move in a cylinder bore of the internal combustion engine; and
a piston bearing cage provided inside the piston, the piston bearing cage including:
at least one inlet port for fluid and at least one outlet port for fluid, wherein the at least one inlet port is obliquely angled from an outer perimeter of the piston bearing cage to direct fluid flowing into the piston from a first trajectory that follows the outer perimeter of the piston bearing cage to a second trajectory towards a center location of the piston.

18. The piston cooling arrangement of claim 17 , further comprising a crown located at a top of the piston, and wherein the at least one inlet port extends along a trajectory toward a center of the crown, the trajectory being obliquely oriented to a direction of movement of the piston in the cylinder bore.

19. The piston cooling arrangement of claim 17 , wherein piston includes a piston pin that connects the piston to a connecting rod, and the at least one inlet port directs the cooling fluid toward an impingement location positioned above the piston pin.

20. The piston cooling arrangement of claim 17 , wherein the at least one inlet port includes a first inlet port on a first side of the piston cooling gallery and a second inlet port on a second side of the piston cooling gallery, the second side being opposite the first side.

Assignees

• Cummins Inc
• Achates Power Inc

Inventors

• Cecil Adam C

Classifications

• F01P3/08 Primary

  Cooling of piston exterior only, e.g. by jets · CPC title

• F02F3/18

  the means being a liquid or solid coolant, e.g. sodium, in a closed chamber in piston · CPC title

• F16J1/005

  obtained by assembling several pieces · CPC title

• F16J1/18

  Securing of gudgeon-pins · CPC title

• F16J1/16 Primary

  with gudgeon-pin; Gudgeon-pins · CPC title