Patent ID: 9163550
Filing Date: 2015-10-20
Classification: F01P

Abstract:
1. An internal combustion engine comprising: a crankshaft; a crankcase supporting the crankshaft; a cylinder block connected to the crankcase and including an upper surface, a lower surface, and a cylinder provided therein; a cylinder head superposed on the cylinder block so as to cover the cylinder; a cooling fan that rotates together with the crankshaft; a shroud arranged to cover a portion of the crankcase, the cooling fan, a portion of the cylinder block, and a portion of the cylinder head; and a plurality of fins are provided at least in a region of the cylinder block covered by the shroud; wherein the plurality of fins include fins provided at the upper surface of the cylinder block and fins provided at the lower surface of the cylinder block; the shroud includes an upper facing wall portion that faces the fins provided at the upper surface of the cylinder block and a lower facing wall portion that faces the fins provided at the lower surface of the cylinder block; and an exhaust opening that discharges air to outside of the shroud and opens on a side of the cylinder block that is opposite to a side of the cylinder block that faces the cooling fan, an end of the exhaust opening being provided directly above the upper surface of the cylinder block and between the upper facing wall portion and the upper surface of the cylinder block, or directly below the lower surface of the cylinder block and between the lower facing wall portion and the lower surface of the cylinder block.