Patent ID: 8397682
Filing Date: 2013-03-19
Classification: F01P,F02F

Abstract:
1. A multiple cylinder engine cooling apparatus comprising: a bottom wall of a cylinder head in which a plurality of combustion chamber forming recesses are formed to line up in a longitudinal direction parallel to an axial direction of a crank shaft; a lower end of a spark plug inserting cylindrical wall extending from each of said recesses upward in a direction opposite to said combustion chambers; a lower end of an inlet port extending from each of said recesses laterally in one direction perpendicular to the longitudinal direction; an exhaust port extending from each of said recesses laterally in the other direction; and a water jacket formed in said cylinder head to cool said bottom wall of said cylinder head, said lower end of said spark plug inserting cylindrical wall, said lower end of said inlet port, and said exhaust port, said water jacket comprising a first water jacket portion through which cooling water flows in the lateral direction from an exhaust port side toward an inlet port side for each cylinder, and a second water jacket portion which is connected to said first water jacket portion through a narrow channel and guides the cooling water from an interior of said first water jacket portion upward along said exhaust port, wherein said first water jacket portion and said second water jacket portion are respectively connected to cooling water discharge ports to discharge cooling water outside said cylinder head, said narrow channel is formed to have a smaller channel sectional area than that of said first water jacket portion or said second water jacket portion, said narrow channel is located on a virtual line extending toward said exhaust port through a center of a cylinder hole when seen from an axial direction of said cylinder, and said narrow channel is formed only at a position adjacent to said spark plug.