Combustion chamber for a supercharged direct-injection combustion engine

摘要

A piston for an internal combustion engine, for example a diesel engine, including a body delimited laterally by a skirt and configured to collaborate with walls of a cylinder of axis of revolution C in which the piston can slide along the axis C, the piston including a transverse face that includes a central pip, a peripheral ring, and a bowl of axis of revolution B that extends from the central pip towards the peripheral ring to which it connects at a lip of thickness Ep. The bowl includes, in substantial vertical alignment with the lip, a torus in profile, for example of a dome-shaped, of maximum radius Rt capable of guiding fuel injected under the lip in a region of a re-entrant zone R towards the central pip. The tip of the pip lying on the axis of revolution B of the bowl rises to a height that is a distance Dt of between 5.4 mm and 8 mm, or substantially equal to 7.2 mm, below the level of the peripheral ring.

主权项

1. A piston for an internal combustion engine, comprising:
a body laterally delimited by a skirt configured to collaborate with walls of a cylinder of axis of revolution (C) in which the piston can slide along the axis (C), the piston comprising a transverse face that comprises a central pip, a peripheral crown ring extending laterally from the skirt, and a bowl of axis of revolution (B) that extends from the central pip toward the peripheral crown ring to which it is connected at a lip of the peripheral crown ring, the bowl comprising, substantially in vertical alignment with the lip, a torus in profile, or of half-dome shaped, configured to guide a fuel injected under the lip in a re-entrance zone (R) toward the central pip, wherein the top of the pip situated on the axis of revolution (B) of the bowl rises up to a height that is a distance (Dt) of between 5.4 mm and 8 mm below the height of a top of the peripheral crown ring, and wherein the lip is situated a distance (De)/2 from the axis of revolution (B) of the bowl, wherein the torus is situated a distance (Db)/2 from the axis of revolution (B) of the bowl, and the distance (Db)/2 of the torus from the axis of revolution (B) of the bowl is greater by substantially 2 mm than the distance (De)/2 of the lip from the axis of revolution (B) of the bowl whereby the lip overhangs the torus, and wherein the maximum depth (P) of the bowl is between 14.8 mm and 16.2 mm.