| 摘要 |
A reciprocating internal combustion engine with direct injection comprises, for each cylinder, a plurality of intake ducts (8a, 8b) each having an inlet portion (9, 13) parallel to the plane of the top of the cylinders and an outlet portion (11, 15) opening into the cylinder (1) in an intake-valve seat (5, 7). The intake ducts (8a, 8b) of each cylinder (1) comprise a main duct (8a) for generating in the fluid a swirling motion coaxial with the axis (A) of the cylinder, and at least one filling duct (8b) which opens in a valve seat (7) upstream of the main duct (8a), with reference to the direction of rotation of the swirling motion. The outlet portion (15) of the filling duct (8b) is scroll-shaped and the inlet portion (13) has a straight mouth portion (13a) and an arcuate guide portion (13b). The resultant (R) of the velocity vector of the fluid passing through the end (16) of the inlet portion (13) is deflected, relative to the axis (A) of the cylinder, in accordance with the rotation of the swirling motion of the fluid in the cylinder (1). |
