Heat engine i.e. spark ignition engine, for motor vehicle, has annular element with upstream section, whose lower bearing forms step provoking rotational movement of admission gas along rotation axis of axis perpendicular to valve seat axis

摘要

The engine has an annular element (22) with a downstream section (28) having a valve seat (30) and an upstream section (32) having a frustoconical lower bearing (34). The lower bearing has a spacing (36) permitting continuous connection of the upstream section with a wall of a bent end section (14) of a molded admission conduit (12) of a cylinder head (10) by filing without altering the end section. The lower bearing forms a step (40) provoking a rotational movement e.g. tumbler movement, of an admission gas along a rotation axis of an axis perpendicular to an axis of the seat. An independent claim is also included for a method for manufacturing a cylinder head of a heat engine.