Piston and internal combustion engine having such a piston

Patent metadata

Field	Value
Publication number	US-12209552-B2
Application number	US-202018038705-A
Country	US
Kind code	B2
Filing date	Nov 27, 2020
Priority date	Nov 27, 2020
Publication date	Jan 28, 2025
Grant date	Jan 28, 2025

Abstract

Piston for an internal combustion engine, preferably a gas engine comprising a pre-chamber, comprising a piston crown limiting the piston on a side facing a cylinder head when the piston is arranged inside an internal combustion engine, wherein the piston crown comprises at least one piston bowl which has a lower surface level than a radial edge region of the piston crown, wherein the piston bowl comprises a depth (d), which is defined by the distance between the radial edge region and the lower surface level of the piston bowl measured parallel to central elevation which has a height (H), wherein the height (H) of the central elevation equals the depth (d) of the piston bowl plus/minus 50%, preferably 20%, of the depth (d) of the piston bowl.

First claim

The invention claimed is:

1. A system, comprising:
a piston for an internal combustion engine, wherein the piston comprises:
a piston crown limiting the piston on a side facing a cylinder head when the piston is arranged inside the internal combustion engine, wherein the piston crown comprises at least one piston bowl having a lower surface level than a radial edge region of the piston crown, wherein the piston bowl comprises a depth, wherein the depth is defined by a distance between the radial edge region and the lower surface level of the piston bowl measured parallel to a center line of the piston, wherein the piston crown comprises a central elevation having a height, wherein the height of the central elevation is in a range of the depth of the piston bowl between plus/minus 20% of the depth of the piston bowl, wherein the piston crown transitions between the radial edge region and the central elevation with curvatures having radii at least greater than the depth of the piston bowl.

2. The system as set forth in claim 1 , wherein the top portion of the central elevation reaches a lower level than the radial edge region of the piston crown measured parallel to the center line of the piston.

3. The system as set forth in claim 1 , wherein the piston crown extends radially inward from an outer diameter of the piston crown having the radial edge region, the piston crown has a first tangential transition from the outer diameter to the piston bowl, and the piston crown has a second tangential transition from the piston bowl to the central elevation.

4. The system as set forth in claim 1 , wherein the top portion of the central elevation reaches a higher level than the radial edge region of the piston crown measured parallel to the center line of the piston.

5. The system as set forth in claim 1 , wherein the central elevation reaches the same height as the radial edge region of the piston crown.

6. The system as set forth in claim 1 , wherein the radial edge region extends essentially at a right angle with respect to the center line of the piston.

7. The system as set forth in claim 1 , wherein the piston bowl is rotationally symmetric around a center line of the piston.

8. The system as set forth in claim 1 , wherein the piston bowl transitions essentially tangentially into the radial edge region of the piston crown.

9. The system as set forth in claim 1 , wherein the piston bowl transitions essentially tangentially into the central elevation of the piston crown.

10. The system as set forth in claim 1 , wherein a first tangential transition from the piston bowl to the radial edge region and/or a second tangential transition from the piston bowl to the central elevation are formed by at least one transition radius.

11. The system as set forth in claim 1 , wherein the piston bowl is formed by a curvature having at least one bowl radius.

12. The system as set forth in claim 1 , wherein the central elevation of the piston crown comprises a spherical portion and is arranged symmetrically around the center line of the piston, with the spherical portion comprising a central elevation radius.

13. The system as set forth in claim 1 , wherein
a first ratio of a transition radius from the piston bowl to the radial edge region and a bowl radius is between 0.5 and 1.5; and
a second ratio of a central elevation radius and the bowl radius is between 0.1 and 0.7.

14. The system as set forth in claim 1 , wherein the piston bowl comprises
a first bowl radius and a second bowl radius, wherein
a first ratio of a transition radius from the piston bowl to the radial edge region and the second bowl radius is between 0.5 and 0.7; and
a second ratio of the second bowl radius and the first bowl radius is between 0.3 and 0.8.

15. The system as set forth in claim 1 , wherein a ratio of a diameter of the piston and the depth of the piston bowl is between 14 and 18.

16. The system as set forth in claim 1 , wherein the piston comprises an upper piston component part and a lower piston component part, wherein the piston crown is arranged at the upper piston component part and a connecting device for connecting the piston with a connecting rod is arranged at the lower piston component part.

17. The system as set forth in claim 1 , comprising the internal combustion engine having at least one pre-chamber and at least one of the piston.

18. The system as set forth in claim 17 , wherein the internal combustion engine has a compression ratio between 10.5 and 14.5.

19. A method, comprising:
forming a piston crown of a piston for an internal combustion engine, wherein the piston crown comprises at least one piston bowl having a lower surface level than a radial edge region of the piston crown, wherein the piston bowl comprises a depth, wherein the depth is defined by a distance between the radial edge region and the lower surface level of the piston bowl measured parallel to a center line of the piston, wherein the piston crown comprises a central elevation having a height, wherein the height of the central elevation is in a range of the depth of the piston bowl between plus/minus 20% of the depth of the piston bowl, wherein the piston crown transitions between the radial edge region and the central elevation with curvatures having radii at least greater than the depth of the piston bowl.

20. A system comprising:
a piston crown of a piston, wherein the piston crown comprises a piston bowl having a lower surface level than a radial edge region of the piston crown, wherein the piston bowl comprises a depth defined by a distance between the radial edge region and the lower surface level of the piston bowl measured parallel to a center line of the piston, wherein the piston crown comprises a central elevation having a height, wherein the height of the central elevation is in a range of the depth of the piston bowl between plus/minus 20% of the depth of the piston bowl, wherein the piston crown transitions between the radial edge region and the central elevation with curvatures having radii at least greater than the depth of the piston bowl.

21. The system of claim 20 , comprising the piston having the piston crown, wherein the piston is configured to reciprocate in a cylinder head of a reciprocating machine.

22. The system of claim 20 , wherein the piston bowl comprises a first curvature having one or more radii between the radial edge region and the central elevation, the central elevation comprises a second curvature, and the first and second curvatures are symmetric about the center line of the piston.

Assignees

• Innio Jenbacher Gmbh & Co Og

Inventors

• Raibel Matthias
• Fuchs Jochen
• Boewing Robert
• Birgel Andreas

Classifications

• F02B19/00 Primary

  Engines characterised by precombustion chambers · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02B43/00

  Engines characterised by operating on gaseous fuels; Plants including such engines (engines characterised by the gas-air charge being ignited by compression ignition of an additional fuel F02B7/06; engines convertible from gas to other fuel consumption F02B69/04) · CPC title

• F02B23/08

  with positive ignition · CPC title

• F02F3/28 Primary

  Other pistons with specially-shaped head · CPC title