초록 ▼

The cylinder head (401) of a turbocompounded 2-stroke piston engine incorporates, for each cylinder (400), an indirect combustion chamber (402) which is connected to the cylinder clearance volume (413) by a passage (412). The indirect combustion chamber (402) incorporates the inlet valve (408) so th

The cylinder head (401) of a turbocompounded 2-stroke piston engine incorporates, for each cylinder (400), an indirect combustion chamber (402) which is connected to the cylinder clearance volume (413) by a passage (412). The indirect combustion chamber (402) incorporates the inlet valve (408) so that when the valve opens, turbocharging air flows into the cylinder through the chamber (402) and the passage (412). This allows a large proportion of the cylinder head area to be devoted to the exhaust valves (410), with advantages in good scavenging and maximizing mass flow rates through the cylinder.

대표청구항 ▼

A turbocompounded 2-stroke piston engine having a cylinder head incorporating, for each cylinder of said piston engine, an indirect combustion chamber, inlet valve means for admitting turbocharging air to the cylinder, and exhaust valve means for exhausting combustion gases from the cylinder, the pi

A turbocompounded 2-stroke piston engine having a cylinder head incorporating, for each cylinder of said piston engine, an indirect combustion chamber, inlet valve means for admitting turbocharging air to the cylinder, and exhaust valve means for exhausting combustion gases from the cylinder, the piston engine being adapted to perform an operating cycle, comprising a compression stroke and an expansion stroke, in which the expansion stroke expands the combustion gases to a pressure lower than the incoming turbocharging air, and in which scavenging of the combustion gases from the cylinder is facilitated by arranging that both the inlet valve means and the exhaust valve means are open at the same time during an early part of the compression stroke so as to purge the cylinder with turbocharging air during said early part of the compression stroke, whereby the cylinder has a compression ratio which is substantially less than its expansion ratio; wherein the inlet valve means is incorporated in the indirect combustion chamber such that when the inlet valve means is open, the incoming turbocharging air flows through the indirect combustion chamber before entering the cylinder, the indirect combustion chamber being connected to the cylinder by passage means for directing the incoming turbocharging air towards the piston thereby to displace the combustion gases towards the exhaust valve means and maximize the efficiency of said scavenging, said indirect combustion chamber incorporating two inlet valves disposed oppositely to each other across the indirect combustion chamber such that inlet obturating portions of the valves move towards each other when the valves are opened.