Internal Combustion Engine

• US 20090007879A1
• Filed: 09/16/2005
• Published: 01/08/2009
• Est. Priority Date: 09/21/2004
• Status: Active Grant

• Current Assignee: Daimler Truck AG (Daimler Truck Holding AG)
• Original Assignee: Daimler Chrysler Company LLC (Stellantis NV)
• Inventors: Hutmacher, Rolf
• Granted Patent: US 8,511,271 B2
• Time in Patent Office: Days
• US Class Current: 123/193.600
• CPC Class Codes: F02B 2275/14 Direct injection into combustion chamber
• CPC Class Codes: F02B 23/0669 having multiple fuel spray jets per injector nozzle
• CPC Class Codes: F02B 23/0696 W-piston bowl, i.e. the combustion space having a central projection pointing towards the cylinder head and the surrounding wall being inclined towards the cylinder wall
• CPC Class Codes: F02B 3/06 with compression ignition compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

In an internal combustion engine having at least one cylinder, in which a combustion chamber is delimited between a piston and a cylinder head, a fuel injector, is arranged in the cylinder head and has an injection nozzle with a plurality of injection bores. A piston depression is arranged in the piston, and a compression projection, with a projection cone angle, is positioned opposite the injection nozzle in the piston depression. The injection bores are formed such that, during a fuel injection in a range from 20° C.A before top dead center to 35° C.A after top dead center, the fuel jets emerging from the injection bores with a fuel cone angle impinge on the piston depression and are guided by a piston depression surface. The injection bores and the compression projection are formed such that a generated ratio of fuel cone angle to projection cone angle is in a range between 0.95 and 1.36, so that the injected fuel mass is distributed uniformly within the piston depressions, and a mixture of fuel with combustion air is intensified.

Claims

1-11. -11. (canceled)

12. An internal combustion engine comprising:

at least one cylinder, in which a combustion chamber is delimited between a piston and a cylinder head,

a fuel injector arranged in the cylinder head and having an injection nozzle with a plurality of injection bores, and

a piston depression arranged in the piston and having a depression base with a maximum depression depth TM,

wherein a compression projection, with a depression angle, is positioned in the piston depression opposite the injection nozzle,

wherein the injection bores are formed such that fuel jets emerge from the injection bores with a fuel cone angle, and

wherein, below a horizontal plane which is aligned with an uppermost part of the depression edge, the piston depression has a depression volume MV and is formed in such a way that a ratio TM/MV of said maximum depression depth TM to said depression volume MV is in a range of front 0.05 to 0.35.

13. The internal combustion engine according to claim 12, wherein the ratio is from 0.1 to 0.25.

14. The internal combustion engine according to claim 12, wherein the piston depression is enclosed by an annular depression edge with a maximum depression diameter DM, wherein the piston has a piston diameter DK, and wherein a ratio DK/DM of said piston diameter to said maximum depression diameter is in a range of from 1.1 to 1.2.

20. The internal combustion engine as claim 12, wherein the fuel jets emerging from the injection bores during a fuel injection which takes place in a range from 20°

C.A before top dead center to 35°

after top dead center impinge on the piston depression, and wherein the injection bores and the compression projection are formed such that a generated ratio β

/α

of fuel cone angle β

to depression angle α

is generated in a range of 0.95 to 1.36.

21. The internal combustion engine as claimed in claim 20, wherein the ratio β

/α

is in a range of 1.15 to 1.3.

15. An internal combustion engine comprising:

at least one cylinder, in which a combustion chamber is delimited between a piston and a cylinder head,

a fuel injector arranged in the cylinder head and having an injection nozzle with a plurality of injection bores,

a piston depression arranged in the piston and having a compression projection, with a depression angle, positioned in the piston depression opposite the injection nozzle,

wherein the injection bores are formed such that, during fuel injection which takes place in a range from 20°

C.A before top dead center to 35°

after top dead center, fuel jets emerging from the injection bores with a fuel cone angle impinge on the piston depression, and

wherein the injection bores and the compression projection are formed such that a generated ratio β

/α

of fuel cone angle β

to depression angle α

is in a range of from 1.15 to 1.3.

16. The internal combustion engine as claimed in claim 15, wherein, below a horizontal plane aligned with an uppermost part of a depression edge, the depression has a depression volume MV and is formed in such a way that a ratio TM/MV of a maximum depression depth TM to said depression volume MV is in a range of from 0.05 to 0.35.

17. The internal combustion engine according to claim 16, wherein said ratio TM/MV is from 0.1 to 0.25.

18. The internal combustion engine as claimed in claim 15, wherein the piston depression is enclosed by an annular depression edge with a maximum depression diameter, wherein the piston has a piston diameter DK, and wherein a ratio DK/DM of the piston diameter to the maximum depression diameter is in a range of from 1.05 to 1.4.

19. The internal combustion engine as claimed in claim 18, wherein the ratio DK/DM is in a range of from 1.1 to 1.2.

22. The internal combustion engine as claimed in claim 15, wherein, below a horizontal plane which is aligned with an uppermost part of the depression edge, the depression has a depression volume MV and is formed in such a way that a ratio TM/MV of a maximum depression depth TM to said depression volume MV is in a range of from 0.05 to 0.35.

23. The internal combustion engine as claimed in claim 22, wherein said range is from 0.1 to 0.25.

24. The internal combustion engine as claimed in claim 23, wherein the piston depression is enclosed by an annular depression edge with a maximum depression diameter DM, wherein the piston has a piston diameter DK, and wherein a ratio DK/DM of the piston diameter DK to the maximum depression diameter DM is in a range between 1.05 and 1.4.

25. The internal combustion engine as claimed in claim 24, wherein said range is from 1.1 to 1.2.

26. The internal combustion engine as claimed in claim 15, wherein the piston depression has a depression base with a maximum depression depth, and wherein a ratio Dmin/DK of a diameter Dmin at the maximum depression depth to a piston diameter DK is in a range of from 0.22 to 0.45.

27. The internal combustion engine as claimed in claim 26, wherein the ratio Dmin/DK is in a range of from 0.3 to 0.39.

28. The internal combustion engine as claimed in claim 15, wherein a piston depression contour has a depression base radius RK between a depression base and a depression edge, and wherein a ratio RK/DM of the depression base radius RK to a maximum depression diameter DM is in a range of from 0.1 to 0.35.

29. The internal combustion engine as claimed in claim 28, wherein the ration RK/DM is in a range of from 0.16 to 0.22.

30. The internal combustion engine as claimed in claim 15, wherein a piston depression contour has a projection radius RH between the compression projection and a depression base, and wherein a ratio RH/DM of the projection radius RH to a maximum depression diameter DM is in a range of from 0.45 to 1.1.

31. The internal combustion engine as claimed in claim 15, wherein the compression projection is formed such that a highest compression projection region is spaced apart from a piston head by a compression spacing H, and wherein a ratio H/TM of the compression spacing H to a maximum depression depth TM is in a range of from 0.1 to 0.45.

32. The internal combustion engine as claimed in claim 31, wherein the ratio H/TM is in a range of from 0.15 to 0.25.