EXHAUST TIMING CONTROL DEVICE OF 2-CYCLE ENGINE

摘要

PURPOSE:To obtain smooth exhaust flow by forming a control valve by providing a control face communicating to an inner face of a cylinder in closing condition of the control valve in a 2-cycle engine in which the control valve opening and closing upper portion of an opening of an exhaust passage communicating to a cylinder in the vicinity thereof. CONSTITUTION:An exhaust pipe 5 forming an exhaust passage 4 having an opening 3 on an inner face 2a of a cylinder is provided integrally on a side portion of the cylinder 2. And control valve 7 opening and closing an upper portion of the opening 3 is provided on a connecting portion of the cylinder 2 and the exhaust pipe 5, and a control face 7a almost continued to the inner face 2a of the cylinder in closing of the exhaust passage 4 is formed on the valve 7. The valve 7 is opened and closed by a drive mechanism 8 which makes an actuator 20 into drive source. The exhaust passage 4 consists of a main exhaust passage 4a having an opening 3a communicating to the inner face 2a of the cylinder and a sub exhaust passage 4b provided on a place apart from the passage 4a to the peripheral direction of the cylinder and provided with an upper edge positioned on a level identical with that of the passage 4a.