Patent ID: 7565886

Claim:
A crankcase scavenged two-stroke internal combustion engine configured to facilitate fluid flow from an air inlet duct to a scavenging duct, said engine comprising: a piston arranged within a cylinder and configured for reciprocating motion therein; an air inlet duct penetrating said cylinder and terminating in an air inlet port at an interior cylinder wall and a scavenging duct penetrating said cylinder and terminating in a scavenging port at said interior cylinder wall, said air inlet port located proximate said scavenging port at said interior cylinder wall; said piston having a recess located in an exterior surface thereof, said recess positioned on said exterior surface of said piston so that said recess comes into common registration with said air inlet port and said scavenging port and thereby establishes a flow channel extending from said air inlet duct, through said air inlet port, across said recess, through said scavenging port and into said scavenging duct; and said flow channel configured to permit straight-line flow from said air inlet duct to said scavenging duct.