Cylinder cooling system of air-cooled engine

摘要

PROBLEM TO BE SOLVED: To provide a cylinder cooling device which can operate a cooling effect by virtue of cooling air from a cooling fan toward the interior of a cylinder even when the thickness of cylinder outer circumferential wall part is thick.;SOLUTION: The cylinder cooling device for air-cooled engine includes: a cooling fan disposed on one end part of a crankshaft; a pair of push rod insertion holes for air intake and exhaust valves arranged with an interval in the shaft direction of the crankshaft formed on a cylinder outer circumferential wall part of the side substantially vertical to the shaft direction of the crankshaft; and a fan shroud for covering the cooling fan and covering a cylinder outer circumferential wall part formed of the push rod insertion holes, wherein a cutout ventilating part formed on the cylinder outer circumferential wall part between the pair of push rod insertion holes and tunnel-shaped ventilating holes which are formed on the cylinder outer circumferential wall part between the push rod insertion holes of the cooling fan side and a cylinder bore, and extend from the cylinder outer circumferential wall part of the cooling fan side to the cutout ventilation part are communicated with each other and the cooling air is guided to the cylinder outer circumferential wall part of the counter-cooling fan side through the tunnel-shaped ventilating holes and the cutout ventilating part.;COPYRIGHT: (C)2012,JPO&INPIT