Patent ID: 8146546
Filing Date: 2012-04-03
Classification: F02B,Y10T

Abstract:
1. In a cylinder block for a two-cycle combustion engine including a scavenging port, open at an inner peripheral surface of the cylinder block, and orient diagonally upwardly relative to a longitudinal axis of a cylinder bore and defined in the cylinder lock in communication with a combustion chamber, the improvement comprising: an air scavenging passage in the cylinder block; a fuel mixture scavenging passage in the cylinder block, wherein the air scavenging passage extends further upward from the fuel mixture scavenging passage in the cylinder block, wherein the air scavenging passage and the fuel mixture scavenging passage communicate with the scavenging port adjacent the inner peripheral surface of the cylinder block; and the scavenging port has an open perimeter edge formed on the inner peripheral surface of the cylinder bore including an upper edge section which includes a flat region at an intermediate portion of the upper edge section and respective inclined regions extending diagonally downwardly from opposite sides of the flat region to associated side perimeter edge sections of the scavenging port.