PISTON

• US 20180306320A1
• Filed: 10/04/2016
• Published: 10/25/2018
• Est. Priority Date: 10/19/2015
• Status: Active Grant

• Current Assignee: Mahle International GmbH (MAHLE-STIFTUNG GmbH)
• Original Assignee: Mahle International GmbH (MAHLE-STIFTUNG GmbH)
• Inventors: Juergen, Rudi, Braig, Ralf
• Granted Patent: US 10,774,931 B2
• Time in Patent Office: Days
• CPC Class Codes: F02F 3/00 Pistons
• CPC Class Codes: F02F 3/0015 Multi-part pistons
• CPC Class Codes: F02F 3/02 having means for accommodating or controlling heat expansion
• CPC Class Codes: F02F 3/022 the pistons having an oval circumference or non-cylindrical shaped skirts, e.g. oval F02F3/025, F02F3/027 take precedence
• CPC Class Codes: F16C 33/1065 Grooves on a bearing surface for distributing or collecting the liquid
• CPC Class Codes: F16J 1/16 with gudgeon-pin; Gudgeon-pins

Abstract

A piston for an internal combustion engine may include two pin bosses configured to receive a gudgeon pin. The two pin bosses may respectively include a nadir pocket of at least two nadir pockets at α=180° and extending outward from a piston axis. The at least two nadir pockets may have a respective length that is smaller than a length of a respective pin boss of the at least two pin bosses. The piston may also include a pin boss axis that is axially offset from the piston axis by 0.1-1.0 mm.

Claims

1. A piston for an internal combustion engine, comprising two pin bosses configured to receive a gudgeon pin, the two pin bosses respectively including a nadir pocket of at least two nadir pockets at α

=180° and

extending outward from a piston axis, the at least two nadir pockets having a respective length that is smaller than a length of a respective pin boss of the at least two pin bosses, wherein a pin boss axis is axially offset from the piston axis by 0.1-1.0 mm.

2. The piston as claimed in claim 1, wherein the respective length of the at least two nadir pockets is 10-75% of the length of the respective pin boss.

3. The piston as claimed in claim 1, wherein the at least two nadir pockets have a depth from 0.1 to 1.0 mm.

4. The piston as claimed in claim 1, wherein a depth of the at least two nadir pockets decreases along the piston axis in a direction extending away from a central axis, the central axis disposed between the two pin bosses and extending perpendicular to the piston axis.

5. The piston as claimed in claim 1, wherein the two pin bosses are configured as one of symmetrically shaped pin bores and asymmetrically shaped pin bores.

6. The piston as claimed in claim 1, wherein the at least two nadir pockets extend over a circumferential angle of 30°

to 130°

.

7. The piston as claimed in claim 1, wherein the two pin bosses have at least one of a superimposed transverse ovality and a vertical ovality.

8. The piston as claimed in claim 1, wherein the two pin bosses include oil pockets.

9. The piston as claimed in claim 1, wherein the two pin bosses include a circumferential lubricating groove.

10. The piston as claimed in claim 8, wherein the oil pockets are at least one of i) narrow straight oil pockets, ii) large straight oil pockets, and iii) oblique large oil pockets.

11. The piston as claimed in claim 2, wherein the at least two nadir pockets have a depth from 0.1 to 1.0 mm.

12. The piston as claimed in claim 11, wherein the depth of the at least two nadir pockets decreases along the piston axis in a direction extending away from a central axis, the central axis disposed between the two pin bosses and extending perpendicular to the piston axis.

13. The piston as claimed in claim 12, wherein the at least two nadir pockets extend over a circumferential angle of 30°

to 130°

.

14. A piston for an internal combustion engine, comprising two pin bosses configured to receive a gudgeon pin, the two pin bosses respectively including a nadir pocket of at least two nadir pockets at α

=180° and

extending outward from a piston axis, the at least two nadir pockets having a respective length that is smaller than a length of a respective pin boss of the at least two pin bosses, the at least two nadir pockets having a depth from approximately 0.1 to 1.0 mm, the depth of the at least two nadir pockets decreasing along the piston axis in a direction extending away from a central axis, the central axis disposed between the two pin bosses and extending perpendicular to the piston axis, wherein a pin boss axis is axially offset from the piston axis by 0.1 to 1.0 mm, the pin boss axis and the piston axis extending perpendicular to the central axis.

15. The piston as claimed in claim 14, wherein the two pin bosses are configured as one of symmetrically shaped pin bores and asymmetrically shaped pin bores.

16. The piston as claimed in claim 14, wherein the at least two nadir pockets extend over a circumferential angle of 30°

to 130°

.

17. The piston as claimed in claim 14, wherein the two pin bosses each include at least one oil pocket and a circumferential lubricating groove.

18. A piston for an internal combustion engine, comprising two pin bosses configured to receive a gudgeon pin, the two pin bosses having at least one of a superimposed transverse ovality and a vertical ovality and respectively including a nadir pocket of at least two nadir pockets at α

=180° and

extending outward from a piston axis, the at least two nadir pockets extending over a circumferential angle of 30°

to 130° and

having a respective length that is smaller than a length of a respective pin boss of the at least two pin bosses, the at least two nadir pockets having a depth from approximately 0.1 to 1.0 mm, the depth of the at least two nadir pockets decreasing along the piston axis in a direction extending away from a central axis, the central axis disposed between the two pin bosses and extending perpendicular to the piston axis, wherein a pin boss axis is axially offset from the piston axis by 0.1 to 1.0 mm, the pin boss axis and the piston axis extending perpendicular to the central axis.

19. The piston as claimed in claim 18, wherein the nadir pocket extends across approximately 10% to 75% a length from the proximal edge to the distal edge.

20. The piston as claimed in claim 19, wherein the two pin bosses are configured as one of symmetrically shaped pin bores and asymmetrically shaped pin bores.