ONE-PIECE CAST PISTON FOR AN INTERNAL COMBUSTION ENGINE

Abstract

A one-piece cast piston (10) for an internal combustion engine includes a cooling channel (12) and at least one rib (18) on the inner side of the piston opposite the recess base of a combustion bowl (14).

Claims

1-4. (canceled)

5. A one-piece cast piston for an internal combustion engine, comprising a cooling channel and at least one rib on the inner side of the piston opposite the recess base of a combustion bowl, wherein when the piston is viewed in the direction of the piston pin axis at least one rib extends in the direction of an area of a piston pin boss which is located essentially at the maximum distance from the piston axis, and that the piston is made from an iron material.

6. The one-piece cast piston for an internal combustion engine according to claim 5, wherein at least one rib extends essentially in the direction of the axis of the piston pin bosses.

7. The one-piece cast piston for an internal combustion engine according to claim 5, wherein the cooling channel extends in the piston axis direction substantially over the whole area of piston-ring grooves.

8. The one-piece cast piston for an internal combustion engine according to claim 5, wherein a lower limiting of the cooling channel in the piston axis direction is located essentially at the same level as a lower groove flank of a lowest piston-ring groove and/or a deepest point of the combustion bowl.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The invention is explained in more detail below using a preferred exemplary embodiment.

[0016] The FIGURE shows a section of a piston according to the invention which is perpendicular to the piston pin axis.

DETAILED DESCRIPTION

[0017] As can be seen in the FIGURE, the piston 10 according to the disclosed embodiment has in its upper area, in the piston axis direction at approximately the same level on the outer face, a ring zone 12 located radially within a preferably closed cooling channel 14 and in the central area a combustion bowl 14. Facing away from the recess base, in a section perpendicular to the piston pin axis in the example shown, there is formed at approximately the deepest point of a o-shaped combustion bowl a thickening or rib 18 on that side of the recess base which is facing away from the combustion chamber, in other words facing towards the piston pin boss 16. In the example shown, two substantially symmetrical ribs are formed which extend essentially parallel to the piston pin axis, that is perpendicular to the drawing plane, towards the side areas of the piston pin boss 16. As can be seen in the FIGURE, the ribs 18 are executed in rounded form on their upper side, which is the underside in the orientation shown. This applies equally for the adjacent areas of the piston underside, so that the respective rib 18, when viewed from the outside to the inside, substantially constitutes a succession of a concave, a convex and a concave curve, which in the example shown transitions into the concave curve of the underside of the combustion bowl 14. It should be mentioned that the described form of the rib 18 can be formed in an advantageous manner when the piston is cast, so that no finishing is required.