| 摘要 |
PURPOSE:To reduce the consumption of fuel and decrease harmful emissions, by providing a long scavenging passage, opening a part of the passage into a cylinder, and using the side surface of a piston to disconnect a portion of the scavenging passage from a crankcase chamber in the processing of scavenging, to effectuate active hot atmosphere burning. CONSTITUTION:The end of a scavenging passage 17, which is opened into a crankcase chamber 8, is placed at the bottom of a crankcase 7 in which the scavenging passage is provided so that the length of the passage for connecting the crankcase chamber 8 to a scavenging port 15 opened in the inside surface of a cylinder 1 is made large. Another scavenging passage 16 is opened into the cylinder 1. The dimensions of a piston 4 and the scavenging passage 16 and a timing are so set that the scavenging passage and the crankcase chamber 8 are disconnected from each other by the side surface of the piston when it is moved down and the scavenging port 15 is opened. A long scavenging passage is thus formed in the process of scavenging to effectuate active hot atmosphere burning to attain the purpose. |
