Patent ID: 8091518

Claim:
A partition member provided in a cylinder block of an internal combustion engine, the engine having a groove-like cooling passage through which a cooling heat medium flows, the partition member being arranged in the groove-like cooling passage, wherein the cooling passage extends to encompass cylinder bores of the cylinder block, wherein the cooling passage has a bottom surface, a pair of opposing inner surfaces, and an opening located opposite to the bottom surface, the partition member comprising: a separating wall that divides the cooling passage into an inner passage and an outer passage, the inner passage being located close to the cylinder bores, the outer passage being located outside of the inner passage, wherein the separating wall has a lower end portion facing the bottom surface of the cooling passage and an upper end portion located opposite to the lower end portion, wherein, when the partition member is arranged in the cooling passage, the height from the bottom surface of the cooling passage to the upper end portion of the separating wall is less than the depth of the cooling passage so that the cooling passage includes an upper area existing above the upper end portion of the separating wall and extending over the entire width between the opposing inner surfaces; and a flexible lip member that extends from the upper end portion of the separating wall toward the opening in such a manner that, when the partition member is arranged in the cooling passage, the lip member contacts one of the inner surfaces at an intermediate position in a direction along the depth of the cooling passage so that the upper area constitutes a portion of one of the inner and outer passages and is separated from the other one of the inner and outer passages, wherein the lip member has a distal edge portion that extends beyond the one inner surface before the partition member is arranged in the cooling passage, and wherein, when the partition member is arranged in the cooling passage, the distal edge portion contacts the one inner surface due to force produced through flexible shape restoration of the lip member.