CAST LIGHT METAL PISTON, IN PARTICULAR AN ALUMINUM PISTON

• US 20150027400A1
• Filed: 03/06/2013
• Published: 01/29/2015
• Est. Priority Date: 03/07/2012
• Status: Active Grant

• Current Assignee: Mahle International GmbH (MAHLE-STIFTUNG GmbH)
• Original Assignee: Mahle International GmbH (MAHLE-STIFTUNG GmbH)
• Inventors: Braig, Ralf, Marquardt, Michael, Adelmann, Jochen
• Granted Patent: US 10,655,561 B2
• Time in Patent Office: Days
• US Class Current: 123/193.6
• CPC Class Codes: F01P 3/10 Cooling by flow of coolant through pistons
• CPC Class Codes: F02F 2003/0007 Monolithic pistons; One piece constructions; Casting of pistons
• CPC Class Codes: F02F 3/0084 the pistons being constructed from specific materials
• CPC Class Codes: F02F 3/20 the means being a fluid flowing through or along piston
• CPC Class Codes: F02F 3/22 the fluid being liquid

Abstract

A cast light metal piston for an internal combustion engine may include a piston crown and a piston skirt adjoining the piston crown. The piston skirt may include two skirt walls arranged on a pressure side and a counterpressure side, respectively. The piston skirt may have two box walls connecting the skirt walls, which conically taper towards one another in a direction of the piston crown. The piston may include an annularly encircling cooling channel. A thickness of the piston crown may amount to a maximum of 4.5 mm.

Claims

1. A cast light metal piston for an internal combustion engine, comprising:

a piston crown and a piston skirt adjoining the piston crown, the piston skirt including two skirt walls arranged on a pressure side and a counterpressure side, respectively, and two box walls connecting the skirt walls, which conically taper towards one another in a direction of the piston crown, and

an annularly encircling cooling channel,

wherein a thickness of the piston crown amounts to a maximum of 4.5 mm.

2. The piston according to claim 1, wherein the thickness of the piston crown amounts to a maximum of 3.5 mm.

3. The piston according to claim 1, wherein the skirt wall arranged on the pressure side is shorter in a circumferential direction of the piston than the skirt wall arranged on the counterpressure side.

4. The piston according to claim 1, wherein the two box walls taper towards one another in a direction of the skirt wall on the pressure side.

5. The piston according to claim 1, wherein at least one of:

the two box walls diverge from one another in a direction of the skirt wall on the pressure side, and

the two box walls converge in the direction of the skirt wall on the counterpressure side.

6. The piston according to claim 1, wherein the cooling channel is formed via at least one of a salt and sand core.

16. The piston according to claim 1, wherein the piston crown and skirt are aluminum.

17. The piston according to claim 2, wherein the skirt wall arranged on the pressure side is shorter in a circumferential direction of the piston than the skirt wall arranged on the counterpressure side.

18. The piston according to claim 3, wherein the two box walls taper towards one another in a direction of the skirt wall on the pressure side.

19. The piston according to claim 4, wherein at least one of:

the box walls diverge from one another in a direction of the skirt wall on the pressure side; and

the two box walls converge in the direction of the skirt wall on the counterpressure side.

7. An internal combustion engine with at least one cast light metal piston, comprising:

a piston crown adjoining a piston skirt, the piston skirt including two skirt walls arranged on a pressure side and a counterpressure side, respectively, and two box walls connecting the skirt walls, the box walls conically tapering towards one another in a direction of the piston crown; and

an annularly encircling cooling channel arranged in the piston crown;

wherein a thickness of the piston crown is 4.5 mm or less.

8. The internal combustion engine according to claim 7, further comprising two spray nozzles for piston cooling, wherein one spray nozzle is directed at an inflow of the cooling channel and the other spray nozzle is directed at the piston crown.

9. The internal combustion engine according to claim 8, wherein the skirt wall arranged on the pressure side is shorter in a circumferential direction of the piston than the skirt wall arranged on the counterpressure side.

10. The internal combustion engine according to claim 7, wherein the thickness of the piston crown is 3.5 mm or less.

11. The internal combustion engine according to claim 7, wherein the skirt wall arranged on the pressure side is shorter in a circumferential direction of the piston than the skirt wall arranged on the counterpressure side.

12. The internal combustion engine according to claim 7, wherein the box walls taper towards one another in a direction of the skirt wall on the pressure side.

13. The internal combustion engine according to claim 7, wherein at least one of:

the box walls diverge from one another in a direction of the skirt wall on the pressure side; and

the two box walls converge in the direction of the skirt wall on the counterpressure side.

14. The internal combustion engine according to claim 7, wherein the cooling channel is formed via at least one of a salt and a sand core.

15. The internal combustion engine according to claim 7, wherein the piston crown and skirt are aluminum.

20. An internal combustion engine, comprising:

at least one aluminum piston, the piston including a piston crown adjoining a piston skirt, the piston skirt including two skirt walls arranged on a pressure side and a counterpressure side, respectively, wherein the skirt wall arranged on the pressure side is shorter in a circumferential direction of the piston than the skirt wall arranged on the counterpressure side, wherein the skirt includes two box walls connecting the skirt walls, the box walls conically tapering towards one another in a direction of the piston crown, wherein the box walls taper towards one another in a direction of the skirt wall on the pressure side and converge in the direction of the skirt wall on the counterpressure side;

an annularly encircling cooling channel disposed in the piston crown; and

at least two spray nozzles for piston cooling, wherein one spray nozzle is directed at an inflow of the cooling channel and the other spray nozzle is directed to the piston crown; and

wherein a thickness of the piston crown is 4.5 mm or less.