Piston for an internal combustion engine

Patent metadata

Field	Value
Publication number	US-10352444-B2
Application number	US-201615763092-A
Country	US
Kind code	B2
Filing date	Sep 13, 2016
Priority date	Sep 25, 2015
Publication date	Jul 16, 2019
Grant date	Jul 16, 2019

Abstract

A piston for an internal combustion engine may include a piston head and a piston skirt. The piston skirt may include a plurality of box walls and a plurality of skirt walls. The plurality of box walls may be arranged opposite one another and may include a plurality of boss bores. The plurality of skirt walls may be arranged opposite one another and may have running surfaces. The piston may also include a cover element that may include a substantially circular cover plate and an aperture. The aperture may be disposed on the cover plate and may be configured for the passage of a connecting rod. The cover element may be secured to a lower region of the piston skirt. The cover plate may close a piston cross-sectional area.

First claim

The invention claimed is:

1. A piston for an internal combustion engine, comprising:
a piston head and a piston skirt;
the piston skirt including a plurality of box walls and a plurality of skirt walls, the plurality of box walls arranged opposite one another and including a plurality of boss bores, the plurality of skirt walls arranged opposite one another and having running surfaces;
a cover element including a cover plate, a plurality of retaining webs that cover the plurality of boss bores from an outside, and an aperture, the aperture disposed on the cover plate and configured for the passage of a connecting rod, the cover element secured to a lower region of the piston skirt;
wherein the cover plate closes a piston cross-sectional area.

2. The piston as claimed in claim 1 , wherein the plurality of retaining webs project from the cover plate toward the piston head and are disposed radially outside the plurality of box walls relative to a central axis of the piston head.

3. The piston as claimed in claim 2 , further comprising an extension complementary to at least one boss bore of the plurality of boss bores arranged on a respective retaining web of the plurality of retaining webs, the extension engaging in the at least one boss bore and closing the at least one boss bore with respect to the outside when the cover element is mounted.

4. The piston as claimed in claim 3 , wherein the respective retaining web and the extension together provide a pin securing mechanism and secure a pin accommodated in the at least one boss bore.

5. The piston as claimed in claim 2 , further comprising a plurality of extensions, each extension of the plurality of extensions configured complementary to a respective boss bore of the plurality of boss bores, wherein each extension is arranged on a respective retaining web of the plurality of retaining webs projecting radially inward therefrom relative to the central axis, wherein each extension is received in and engages the respective boss bore and closes the respective boss bore with respect to the outside when the cover element is mounted.

6. The piston as claimed in claim 5 , wherein each extension has a radially inward facing surface which is sloped radially outward in an axial direction, relative to the central axis, from the lower region of the piston skirt to the piston head.

7. The piston as claimed in claim 1 , wherein the cover plate includes an aperture rim projecting toward the piston head and surrounding the aperture.

8. The piston as claimed in claim 1 , wherein the cover plate includes at least one edge rim projecting toward the piston head and extending at least partial around an outer edge of the cover plate.

9. The piston as claimed in claim 1 , wherein the cover element includes an injection opening through which oil is injectable.

10. The piston as claimed in claim 9 , wherein the injection opening is surrounded by an injection opening rim projecting from the cover plate toward the piston head.

11. The piston as claimed in claim 1 , wherein the cover plate completely closes the piston cross-sectional area.

12. The piston as claimed in claim 1 , wherein plurality of box walls are arranged radially inwards from an outer circumference of the piston head relative to a central piston axis of the piston head and define a radial extent smaller than a radial extent of the piston head.

13. The piston as claimed in claim 12 , wherein the cover plate covers a cross-sectional area defined between the plurality of box walls and the outer circumference of the piston head.

14. The piston as claimed in claim 1 , wherein the cover element is connected to the plurality of box walls in a region of the plurality of boss bores.

15. The piston as claimed in claim 14 , wherein the cover element is connected to the plurality of box walls via at least one of i) a brazed connection, ii) an adhesively bonded connection, and iii) a welded connection.

16. A piston, comprising:
a piston head;
a piston skirt including a plurality of boss bores, a plurality of box walls arranged opposite one another and radially inward from an outer circumference of the piston head relative to a central axis of the piston head, and a plurality of skirt walls arranged opposite one another and having running surfaces, the plurality of box walls and the plurality of skirt walls defining a piston cross-sectional area at a lower region of the piston skirt disposed opposite the piston head; and
a cover element couplable to the plurality of box walls in a region of the plurality of boss bores, the cover element including a cover plate and an aperture, the aperture disposed on the cover plate and configured for the passage of a connecting rod, wherein the cover plate closes the piston cross-sectional area at the lower region of the piston skirt when the cover element is coupled to the plurality of box walls;
wherein the cover plate extends radially beyond the plurality of box walls relative to the central axis when the cover element is coupled to the plurality of box walls.

17. The piston as claimed in claim 16 , wherein the cover element further includes a plurality of retaining webs structured and arranged to cover the plurality of boss bores from an outside when the cover element is coupled to the plurality of box walls.

18. The piston as claimed in claim 17 , further comprising a plurality of extensions, each extension of the plurality of extensions configured complementary to a respective boss bore of the plurality of boss bores and arranged on a respective retaining web of the plurality of retaining webs, wherein each extension engages the respective boss bore and closes the respective boss bore with respect to the outside when the cover element is coupled to the piston.

19. A piston, comprising:
a piston head;
a piston skirt including a plurality of boss bores, a plurality of box walls arranged opposite one another, and a plurality of skirt walls arranged opposite one another and each having a running surface, the plurality of box walls and the plurality of skirt walls defining a piston cross-sectional area at a lower region of the piston skirt disposed opposite the piston head; and
a cover element couplable to the plurality of box walls in a region of the plurality of boss bores, the cover element including a cover plate and an aperture, the aperture disposed on the cover plate and configured for the passage of a connecting rod, wherein the cover plate closes the piston cross-sectional area at the lower region of the piston skirt when the cover element is coupled to the plurality of box walls;
wherein an outer edge of the cover plate includes a plurality of notches extending radially inward relative to a central axis of the piston head, each of the plurality of notches structured complimentary to a respective skirt wall of the plurality of skirt walls and arranged to receive the respective skirt wall when the cover element is mounted.

20. The piston as claimed in claim 19 , wherein a remaining un-notched portion of the outer edge of the cover plate is axially aligned with an outer circumference of the piston head relative to the central axis when the cover element is mounted.

Assignees

• Mahle Int Gmbh

Inventors

• Hirsch Markus A
• Walch Markus

Classifications

• F16J1/09 Primary

  with means for guiding fluids (F16J1/08 takes precedence) · CPC title

• F02F3/20

  the means being a fluid flowing through or along piston · CPC title

• F16J1/005

  obtained by assembling several pieces · CPC title

• F01P3/10

  Cooling by flow of coolant through pistons · CPC title