PISTON INCLUDING A PAIR OF COOLING CHAMBERS

• US 20130032103A1
• Filed: 08/04/2011
• Published: 02/07/2013
• Est. Priority Date: 08/04/2011
• Status: Active Grant

• Current Assignee: Tenneco Incorporated (Apollo Global Management, Inc.)
• Original Assignee: Federal-Mogul Corporation (Apollo Global Management, Inc.)
• Inventors: Azevedo, Miguel
• Granted Patent: US 8,544,441 B2
• Time in Patent Office: Days
• US Class Current: 123/41.35
• CPC Class Codes: F01P 3/06 Arrangements for cooling pistons
• CPC Class Codes: F02F 3/22 the fluid being liquid
• CPC Class Codes: F02F 3/225 the liquid being directed into blind holes
• CPC Class Codes: Y10T 29/49249 Piston making

Abstract

A piston for an internal combustion engine including a piston body (20). The piston body (20) defines a first cooling chamber (46) that is sealed closed and contains a first cooling medium (48) other than air. During operation of the piston, the first cooling medium (48) extracts heat from the surrounding regions of the piston body (20) to cool the piston body (20). The piston body (20) also defines a second cooling chamber (50) adjacent to the first cooling chamber (46). A cooling oil (51) is projected into the second cooling chamber (50) and against the portion of the piston body (20) separating the first and second cooling chambers (46, 50) to extract heat from the first cooling medium (48). The cooling oil (51) is redirected within the second cooling chamber (50) to extract additional heat from the first cooling medium (48) or directly from the piston body (20).

Claims

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

a piston body having a first cooling chamber that is sealed closed and which contains therein a first cooling medium other than air which is operative during operation of the piston to extract heat from surrounding regions of said piston body; and

a second cooling chamber disposed adjacent said first cooling chamber and which is at least partially open to receive a flow of cooling oil into said second cooling chamber during operation of said piston to extract additional heat from said piston body.

2. The piston as set forth in claim 1 wherein said piston body defines a wall separating said first cooling chamber from said second cooling chamber for transferring heat from the first cooling medium contained in said first cooling chamber to the cooling oil received in said second cooling chamber.

3. The piston as set forth in claim 2 further including a flange spaced from said wall to define said second cooling chamber and wherein said second cooling chamber is open in a radial direction.

4. The piston as set forth in claim 3 wherein said flange presents at least one aperture through which the cooling oil flows into the second cooling chamber during operation of said piston.

5. The piston as set forth in claim 1 wherein said piston body includes a crown and a skirt.

6. The piston as set forth in claim 5 wherein said first cooling chamber is disposed in said crown of said piston body.

7. The piston as set forth in claim 6 wherein said crown presents a top surface having a flat outer periphery to define a bowl rim.

8. The piston as set forth in claim 7 wherein said first cooling chamber is disposed in said crown adjacent to said bowl rim for extracting heat from said bowl rim of said piston.

9. The piston as set forth in claim 6 wherein said crown defines at least one groove extending circumferentially around said crown.

10. The piston as set forth in claim 9 further including at least one piston ring disposed in said groove of said crown.

11. The piston as set forth in claim 10 wherein said first cooling chamber is disposed in said crown adjacent to said groove for extracting heat from said piston ring.

12. The piston as set forth in claim 1 wherein the first cooling medium has a melting point of between fifty and two hundred degrees Celsius.

13. The piston as set forth in claim 12 wherein the first cooling medium has a melting point of approximately one hundred degrees Celsius.

14. The piston as set forth in claim 13 wherein the first cooling medium is sodium or a sodium-based compound.

15. A method of cooling a piston in an internal combustion engine, comprising the steps of:

providing a piston body including a first cooling chamber and a second cooling chamber adjacent the first cooling chamber;

sealing a first cooling medium in the first cooling chamber for extracting heat from the surrounding regions of the piston body; and

providing at least one opening in the second cooling chamber for receiving a cooling oil to extract additional heat from the piston body.

16. The method as set forth in claim 15 wherein the piston body defines a wall separating the first and second cooling chambers for transferring heat from the first cooling medium to the cooling oil.

17. The method as set forth in claim 15 further including the step of projecting the cooling oil into the second cooling chamber to extract heat from the piston body and the first cooling medium.

18. The method as set forth in claim 17 further including the step of redirecting the second cooling oil in the second cooling chamber against the piston body to extract additional heat from the piston body and the first cooling medium.

19. The method as set forth in claim 15 further including the step of shaking the first cooling medium within the first cooling chamber to transfer heat from the piston body to the first cooling medium.

20. The method as set forth in claim 15 wherein the piston body includes a bowl rim and a plurality of grooves each supporting a piston ring and wherein the first cooling chamber is disposed adjacent to the bowl rim and the grooves for extracting heat from the bowl rim and the piston rings.