Patent ID: 7677219

Claim:
A cylinder head, comprising: a bottom wall portion, disposed on a side which faces a cylinder block to make a base portion; an outer circumferential wall portion, erected from a circumference of the bottom wall portion, and defining inside thereof a space where an intake camshaft, an exhaust camshaft and variable valve actuating units adapted to vary actuation of intake valves are disposed; a longitudinal wall portion, holding an injector for injecting fuel into an interior of a combustion chamber, and extending to define, inside of the outer circumferential wall portion, an intake side where the intake camshaft is disposed and an exhaust side where the exhaust camshaft is disposed, both ends of which are integrally formed with the outer circumferential wall portion; first intake-side lateral wall portions, formed with intake camshaft support portions for supporting the intake camshaft thereon, which are arranged in the intake side, one ends of which are integrally formed with the longitudinal wall portion, and the other ends of which are integrally formed with a portion of the outer circumferential wall portion which confronts the longitudinal wall portion; second intake-side lateral wall portions, formed with support portions for supporting the variable valve actuating units thereon, which are arranged in the intake side, one ends of which are integrally formed with the longitudinal wall portion, and the other ends of which are integrally formed with the portion of the outer circumferential wall portion which confronts the longitudinal wall portion; and exhaust-side lateral wall portions, formed with exhaust camshaft support portions for supporting the exhaust camshaft thereon, which are arranged in the exhaust side, one ends of which are integrally formed with the longitudinal wall portion, and the other ends of which are integrally formed with a portion of the outer circumferential wall portion which confronts the longitudinal wall portion, characterized in that the second intake-side lateral wall portions are arranged alternately with the first intake-side lateral wall portions, and are lower than the first intake-side lateral wall portions in a height direction from the bottom wall portion, the exhaust-side lateral wall portions are arranged between the first intake-side lateral wall portions, and are higher than the second intake-side lateral wall portions in the height direction from the bottom wall portion, and an upper end face of the bottom wall portion, which is disposed on the exhaust side, is higher than an upper end face of the bottom wall portion, which is disposed on the intake side.