Internal combustion engines with at least two rows of cylinders with overhead camshafts

Claim 1

In an internal combustion engine comprising at least two similar rows of several cylinders, an interchangeable overhead camshaft drive arrangement, wherein the camshafts of the two rows of cylinders are rotated, through two chain or notched belt transmission devices and gears, through an intermediate shaft arranged between said rows of cylinders parallel to the latter and itself rotated by the crankshaft of the engine through a generally reducing transmission device, the two said transmission devices including respectively two drive gears keyed on the said intermediate shaft at positions selected so that the corresponding driven gears borne by the camshafts are situated between two cams relating to two successive cylinders of the corresponding row of cylinders, whereby reduction in the length of the camshafts and in the engine cylinder head is effected, wherein the driven gears of two corresponding camshafts, belonging respectively to the two similar rows of several cylinders, occupy symmetrical positions with respect to the axis enabling the cylinder heads of the two rows of cylinders to be made theoretically to coincide by rotation through 180* around the said axis, wHereby it is possible to adopt identical cylinder heads for the two said rows of cylinders.