Patent ID: 6536399
Filing Date: 2003-03-25
Classification: F02B,F02F

Abstract:
A crankshaft supporting structure for a horizontally opposed type internal combustion engine, the engine including a crankshaft having a plurality of journals, first and second pluralities of pistons connected to the crankshaft and disposed opposite to each other with the crankshaft therebetween and arranged with an offset from each other along an axial direction of the crankshaft, a crankcase for containing and supporting the crankshaft, and first and second cylinder blocks connected to and disposed on opposite sides of the crankcase and having cylinder bores for slidably receiving therein the first and second pluralities of pistons, respectively, the crankcase being split along a plane containing an axis of the crankshaft into first and second case halves connected respectively with the first and second cylinder blocks, said crankshaft supporting structure comprising:said first and second case halves being integrally provided with first and second journal supporting walls, respectively, for rotatably supporting a middle journal of said plurality of journals of the crankshaft therebetween, said first and second journal supporting walls for facing the cylinder bores of the first and second cylinder blocks; and said first and second journal supporting walls being connected by a plurality of first bolts inserted from a side of the cylinder bores of the first cylinder block and disposed on opposite sides of and in proximity to the middle journal, the plurality of first bolts opening into the cylinder bores.