Piston of an internal combustion engine

Patent metadata

Field	Value
Publication number	US-9670829-B2
Application number	US-201314391388-A
Country	US
Kind code	B2
Filing date	Apr 12, 2013
Priority date	Apr 13, 2012
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

An engine block of an internal combustion engine is disclosed. The engine block may have a piston and at least one gas exchange valve. The piston may have a piston skirt having a first center axis. The piston may also have a piston head delimiting the piston skirt at the top with a diameter D. The piston head may have a piston head edge and a piston head recess with a piston recess wall having a height H. At least one valve pocket may be formed into the piston head edge. The at least one valve pocket may have a valve pocket depth T with respect to the piston head edge. The valve pocket depth T may fulfill the following condition with respect to the wall height H: 0.05 H<=T<=0.5H.

First claim

The invention claimed is:

1. A piston of an internal combustion engine, comprising:
a piston skirt having a centre axis; and
a piston head delimiting the piston skirt to a top, the piston head having a diameter D and including:
a piston head edge;
a piston head recess with a piston recess wall having a wall height H; and
at least one valve pocket formed in the piston head edge, the at least one valve pocket having a valve pocket bottom disposed at a valve pocket depth T with respect to the piston head edge adjacent the piston skirt, the valve pocket bottom being inclined relative to the centre axis, wherein the valve pocket depth T with respect to the wall height H fulfils the following condition, at least in the region of the piston recess wall: 0.05 H<=T<=0.5 H.

2. The piston according to claim 1 , wherein the valve pocket bottom is inclined relative to the centre axis by an angle β, with 1°<=β<=25°, wherein the depth T increases towards the piston head recess.

3. The piston according to claim 1 , wherein the at least one valve pocket is a first valve pocket and the piston includes a plurality of valve pockets.

4. The piston according to claim 3 , wherein a second valve pocket selected from the valve pockets has a second valve pocket bottom with a second surface normal arranged in an inclined manner relative to the center axis by an angle β.

5. The piston according to claim 4 , wherein the angle β ranges from 1° to 25° and the depth T increases towards the piston head recess.

6. An engine block of an internal combustion engine, comprising:
a piston guided in the engine block, including:
a piston skirt having a first centre axis; and
a piston head delimiting the piston skirt to a top, with a diameter D, wherein the piston head includes:
a piston head edge;
a piston head recess with a piston recess wall having a wall height H; and
at least one valve pocket formed in the piston head edge, the at least one valve pocket having a valve pocket bottom; and

at least one gas exchange valve having a second centre axis, the at least one gas exchange valve configured to be disposed partially within the at least one valve pocket at a distance “a” from the valve pocket bottom, wherein the distance a increases to a distance A at least in the region of the piston recess wall, with A>=a+2 mm.

7. The engine block according to claim 6 , the distance A fulfilling the following condition: 0.05 H<=A<=0.5 H.

8. The engine block according to claim 6 , the valve pocket bottom having a surface normal N arranged in an inclined manner to the first centre axis by an angle β, with 1°<=β<=25°.

9. The engine block according to claim 6 , the valve pocket having a depth T, at least in the region of the piston recess wall, wherein the depth T with respect to the height H fulfils the following condition: 0.05 H<=T<=0.5 H.

10. The engine block according to claim 6 , wherein the distance a is a minimum distance for ensuring a free movement of the open gas exchange valve, and a depth T of the valve pocket bottom adjacent the piston skirt exceeds the distance a by at least 1 mm.

11. An engine, comprising:
a piston, including:
a piston skirt having a centre axis; and
a piston head delimiting the piston skirt to a top, the piston head having a diameter D and including:
a piston head edge;
a piston head recess with a piston recess wall having a wall height H; and
at least one valve pocket formed in the piston head edge, the at least one valve pocket having a valve pocket bottom disposed at a valve pocket depth T with respect to the piston head edge adjacent the piston skirt, the valve pocket bottom being inclined relative to the centre axis, wherein the valve pocket depth T with respect to the wall height H fulfils the following condition, at least in the region of the piston recess wall: 0.05 H<=T<=0.5 H.

12. An engine comprising an engine block including:
a piston guided in the engine block, including:
a piston skirt having a first centre axis; and
a piston head delimiting the piston skirt to a top, with a diameter D, wherein the piston head includes:
a piston head edge;
a piston head recess with a piston recess wall having a wall height H; and
at least one valve pocket formed in the piston head edge, the at least one valve pocket having a valve pocket bottom; and

at least one gas exchange valve having a second centre axis, the at least one gas exchange valve configured to be disposed partially within the at least one valve pocket at a distance “a” from the valve pocket bottom, wherein the distance a increases to a distance A at least in the region of the piston recess wall, with A>=a+2 mm.

13. The engine according to claim 12 , wherein the valve pocket bottom has a surface normal arranged in an inclined manner relative to the first centre axis by an angle β, with 1°<=β<=25°.

14. The engine according to claim 12 , wherein the engine comprises at least one of a diesel engine, an Otto engine, and an Otto gas engine.

15. The engine according to claim 12 , wherein the at least one valve pocket is a first valve pocket and the piston includes a plurality of valve pockets.

16. The engine according to claim 15 , wherein a second valve pocket selected from the valve pockets has a second valve pocket bottom with a second surface normal arranged in an inclined manner relative to the first center axis by an angle β.

17. The engine according to claim 12 , wherein the distance a is a minimum distance for ensuring a free movement of the open as exchange valve, and a depth T of the valve pocket bottom adjacent the piston skirt exceeds the distance a by at least 1 mm.

18. The engine according to claim 12 , the distance A fulfilling the following condition: 0.05 H<=A<=0.5 H.

19. The engine according to claim 12 , wherein the distance A fulfils the condition a+1 mm<A<a+20 mm.

20. The engine according to claim 12 , the valve pocket having a depth T, at least in the region of the piston recess wall, wherein the depth T with respect to the height H fulfils the following condition: 0.05 H<=T<=0.5 H.

Assignees

• Caterpillar Energy Solutions Gmbh

Inventors

• Böwing Robert
• Drehobl Enrico
• Drexel Christian
• Rapp Manfred

Classifications

• F02B23/0639 Primary

  the combustion space having substantially the shape of a cylinder · CPC title

• Y02T10/125

  Cross-Sectional Technologies · mapped topic

• F02F3/28

  Other pistons with specially-shaped head · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02F3/26

  having combustion chamber in piston head (the surface thereof being covered F02F3/14) · CPC title