Engine cylinder block reinforcing structure

摘要

An engine cylinder block structure includes: a cylinder block integrally formed to include skirts projecting downwardly from both sides of the lower surface of the cylinder block; an oil pan attached to lower surfaces of both skirts of the cylinder block, the oil pan having a deep first portion on a front side and a shallow second portion on a rear side, the first and second portions being connected to each other; flanges integrally formed on lower ends of the skirts for having the oil pan attached thereto; and reinforcing mechanism for reinforcing the strength of both skirts. The reinforcing mechanism includes: a plate-shaped reinforcing member for reinforcing the strength of both skirts, the plate-shaped reinforcing member spanning and interconnecting portions corresponding to a range extending between the first portion of the oil pan and a portion excluding the rear end of the second portion of the oil pan; and stiffening mechanism for providing portions of the flanges corresponding to the second portion of the oil pan with a rigidity higher than that of portions of the flanges corresponding to the first portion of the oil pan.