四冲程桨油机工作原理 Air fuel Exhaust gas 空气、油 废气 Intake valve Exhaust valve 吸气压缩 Intake Compression膨胀 排气 Expansion Exhaust四冲程柴油机工作原理 空气、油 废气 吸气 压缩 膨胀 排气 Intake Compression Expansion Exhaust Air, Fuel Exhaust gas Intake valve Exhaust valve