Assembly of a piston and an oil spray nozzle for an internal combustion engine

Patent metadata

Field	Value
Publication number	US-10260452-B2
Application number	US-201515303220-A
Country	US
Kind code	B2
Filing date	Apr 9, 2015
Priority date	Apr 11, 2014
Publication date	Apr 16, 2019
Grant date	Apr 16, 2019

Abstract

An assembly for cooling oil for an internal combustion engine may include a piston having a piston head and a piston skirt. The piston head may include a piston crown with an undersurface having an outer region configured as a guiding surface for the cooling oil, a circumferential ring part, and, in a region of the circumferential ring part, a circumferential cooling channel with at least one feed opening for the cooling oil. The assembly may also include a first oil spray nozzle for creating a first cooling oil jet directed at the feed opening, and a second oil spray nozzle for creating a second cooling oil jet directed at the guiding surface such that the second cooling oil jet may deflect and flow along the guiding surface in a direction of the undersurface. At least the first oil spray nozzle may be positioned below the piston skirt.

First claim

The invention claimed is:

1. An assembly for cooling oil for an internal combustion engine, comprising:
a piston having a piston head and a piston skirt, the piston head including a piston crown with an undersurface having an outer region configured as a guiding surface for the cooling oil, a circumferential ring part, and in a region of the circumferential ring part a circumferential cooling channel with at least one feed opening for the cooling oil;
a first oil spray nozzle for creating a first cooling oil jet directed at the at least one feed opening; and
a second oil spray nozzle for creating a second cooling oil jet directed at the guiding surface so that the second cooling oil jet impinges on a defined starting point such that the second cooling oil jet is deflected, proceeding from the defined starting point, in a direction of the guiding surface and a resulting cooling oil flow streams along the guiding surface in a direction of the undersurface of the piston crown;
wherein at least the first oil spray nozzle is positioned below the piston skirt; and
wherein the guiding surface is less steep than the rest of the undersurface with respect to a center axis of the piston.

2. The assembly as claimed in claim 1 , wherein a center axis of the first oil spray nozzle is oriented parallel to the center axis of the piston.

3. The assembly as claimed in claim 1 , wherein a center axis of the second oil spray nozzle is oriented inclined in relation to the center axis of the piston.

4. The assembly as claimed in claim 1 , wherein the first oil spray nozzle has a larger nozzle cross section than the second oil spray nozzle.

5. The assembly as claimed in claim 1 , further comprising a connecting rod accommodated inside the piston, wherein a distance between the defined starting point and the center axis of the piston is 1.2 to 1.6 times an outer radius of a small connecting rod eye of the connecting rod.

6. The assembly as claimed in claim 1 , wherein the guiding surface subtends an angle of 15 degrees to 55 degrees from a horizontal line running perpendicular to the center axis of the piston.

7. The assembly as claimed in claim 6 , wherein the undersurface subtends an angle from the horizontal line, wherein a difference between the respective angles of the guiding surface and the undersurface is at most 15 degrees.

8. The assembly as claimed in claim 1 , wherein the guiding surface passes into the undersurface at a defined point.

9. The assembly as claimed in claim 8 , wherein the guiding surface passes steadily into the undersurface.

10. The assembly as claimed in claim 1 , wherein the piston skirt is thermally decoupled from the piston head.

11. The assembly as claimed in claim 1 , wherein the piston skirt has two piston bosses joined together by two running surfaces having respective inner surfaces, wherein the inner surface of one of the running surfaces at a pressure side of the piston is joined by a connection web to the undersurface of the piston crown.

12. The assembly as claimed in claim 1 , wherein the piston is assembled from at least two permanently joined components.

13. The assembly as claimed in claim 12 wherein the at least two permanently joined components include a piston base body and a piston ring element.

14. An assembly for cooling oil for an internal combustion engine, comprising:
a piston having a piston head and a piston skirt, the piston head including a piston crown with an undersurface having an outer region configured as a guiding surface for the cooling oil, a circumferential ring part, and in a region of the circumferential ring part a circumferential cooling channel with at least one feed opening for the cooling oil;
a first oil spray nozzle for creating a first cooling oil jet directed at the at least one feed opening;
a second oil spray nozzle for creating a second cooling oil jet directed at the guiding surface so that the second cooling oil jet impinges on a defined starting point such that the second cooling oil jet is deflected, proceeding from the defined starting point, in a direction of the guiding surface and a resulting cooling oil flow streams along the guiding surface in a direction of the undersurface of the piston crown; and
a connecting rod accommodated inside the piston, wherein a distance between the defined starting point and a center axis of the piston is 1.2 to 1.6 times an outer radius of a small connecting rod eye of the connecting rod;
wherein the first oil spray nozzle and the second spray nozzle are positioned below the piston skirt; and
wherein a center axis of the first oil spray nozzle is oriented parallel to the center axis of the piston, and a center axis of the second oil spray nozzle is oriented inclined in relation to the center axis of the piston.

15. The assembly as claimed in claim 14 , wherein the first oil spray nozzle has a larger nozzle cross section than the second oil spray nozzle.

16. The assembly as claimed in claim 1 , wherein the guiding surface passes into the undersurface at a defined point.

17. The assembly as claimed in claim 14 , wherein the guiding surface subtends an angle of 15 degrees to 55 degrees from a horizontal line running perpendicular to the center axis of the piston.

18. The assembly as claimed in claim 17 , wherein the undersurface subtends an angle from the horizontal line, wherein a difference between the respective angles of the guiding surface and the undersurface is at most 15 degrees.

19. An assembly for cooling oil for an internal combustion engine, comprising:
a piston having a piston head and a piston skirt, the piston head including a piston crown with an undersurface having an outer region configured as a guiding surface for the cooling oil, a circumferential ring part, and in a region of the circumferential ring part a circumferential cooling channel with at least one feed opening for the cooling oil;
a first oil spray nozzle for creating a first cooling oil jet directed at the at least one feed opening;
a second oil spray nozzle for creating a second cooling oil jet directed at the guiding surface so that the second cooling oil jet impinges on a defined starting point such that the second cooling oil jet is deflected, proceeding from the defined starting point, in a direction of the guiding surface and a resulting cooling oil flow streams along the guiding surface in a direction of the undersurface of the piston crown; and
a connecting rod accommodated inside the piston, wherein a distance between the defined starting point and a center axis of the piston is 1.2 to 1.6 times an outer radius of a small connecting rod eye of the connecting rod;
wherein at least the first oil spray nozzle is positioned below the piston skirt.

Assignees

• Mahle Int Gmbh

Inventors

• Linke Timo
• Scharp Rainer

Classifications

• F01P3/10

  Cooling by flow of coolant through pistons · CPC title

• F02F3/22 Primary

  the fluid being liquid · CPC title

• F01P3/08

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