Abstract: The disclosure provides a multi-cylinder internal combustion engine having a cylinder head that includes an exhaust port capable of cooling exhaust gas more effectively. The cylinder head includes: a first ceiling surface that closes a first cylinder having a cylinder axis separated from an exhaust opening by a first distance; a second ceiling surface that closes a second cylinder having a cylinder axis separated from the exhaust opening by a second distance shorter than the first distance; and an exhaust port that extends toward the exhaust opening from two port openings which are open to a combustion chamber for each individual cylinder. The exhaust port individually extends from each of the port openings and merges with each cylinder outside a joining surface of the cylinder head for a cylinder block in a plan view.

Abstract: The disclosure provides a multi-cylinder internal combustion engine having a cylinder head that includes an exhaust port capable of cooling exhaust gas more effectively. The cylinder head includes: a first ceiling surface that closes a first cylinder having a cylinder axis separated from an exhaust opening by a first distance; a second ceiling surface that closes a second cylinder having a cylinder axis separated from the exhaust opening by a second distance shorter than the first distance; and an exhaust port that extends toward the exhaust opening from two port openings which are open to a combustion chamber for each individual cylinder. The exhaust port individually extends from each of the port openings and merges with each cylinder outside a joining surface of the cylinder head for a cylinder block in a plan view.

Abstract: To improve the oil separation performance in an oil separation device for an internal combustion engine. The oil separation device (10) comprises a gas liquid separation passage (56) internally defined by a lower wall, an upper wall and a pair of side walls, and extending in a horizontal direction, a gas inlet (54) and a gas outlet (63) provided on either end of the gas liquid separation passage, a plurality of lower partition walls (56H) projecting upward from the lower wall, and a plurality of upper partition walls (56J) projecting downward from the upper wall. The lower partition walls and the upper partition wall are tilted with respective the length wise direction in plan view so as to define a spiral passage. The lower wall is inclined with respect to a horizontal plane such that an upstream part of the lower wall is lower than a downstream part of the lower wall with respect to a direction of the swirl flow.

Abstract: To improve the oil separation performance in an oil separation device for an internal combustion engine. The oil separation device (10) comprises a gas liquid separation passage (56) internally defined by a lower wall, an upper wall and a pair of side walls, and extending in a horizontal direction, a gas inlet (54) and a gas outlet (63) provided on either end of the gas liquid separation passage, a plurality of lower partition walls (56H) projecting upward from the lower wall, and a plurality of upper partition walls (56J) projecting downward from the upper wall. The lower partition walls and the upper partition wall are tilted with respective the length wise direction in plan view so as to define a spiral passage. The lower wall is inclined with respect to a horizontal plane such that an upstream part of the lower wall is lower than a downstream part of the lower wall with respect to a direction of the swirl flow.

Abstract: To improve the oil separation performance in an oil separation device for an internal combustion engine. The oil separation device (10) comprises a gas liquid separation passage (56) internally defined by a lower wall, an upper wall and a pair of side walls, and extending in a horizontal direction, a gas inlet (54) and a gas outlet (63) provided on either end of the gas liquid separation passage, a plurality of lower partition walls (56H) projecting upward from the lower wall, and a plurality of upper partition walls (56J) projecting downward from the upper wall. The lower partition walls and the upper partition wall are tilted with respective the length wise direction in plan view so as to define a spiral passage. The lower wall is inclined with respect to a horizontal plane such that an upstream part of the lower wall is lower than a downstream part of the lower wall with respect to a direction of the swirl flow.

Abstract: To improve the oil separation performance in an oil separation device for an internal combustion engine. The oil separation device (10) comprises a gas liquid separation passage (56) internally defined by a lower wall, an upper wall and a pair of side walls, and extending in a horizontal direction, a gas inlet (54) and a gas outlet (63) provided on either end of the gas liquid separation passage, a plurality of lower partition walls (56H) projecting upward from the lower wall, and a plurality of upper partition walls (56J) projecting downward from the upper wall. The lower partition walls and the upper partition wall are tilted with respective the length wise direction in plan view so as to define a spiral passage. The lower wall is inclined with respect to a horizontal plane such that an upstream part of the lower wall is lower than a downstream part of the lower wall with respect to a direction of the swirl flow.

Abstract: In an auxiliary device mounting structure for mounting an auxiliary device (4) on a cylinder head (2), the auxiliary device such as a fuel injection pump is provided with a lower housing (42) attached to the cylinder head, and the upper housing (43) supporting the auxiliary device and attached to the lower housing so as to jointly form a housing chamber (48). An extension (51) of a camshaft (37) extends into the housing chamber, and is fitted with a cam (61) for actuating a plunger (86) of the auxiliary device. A radial bearing (53, 56) for the camshaft extension is integrally formed on the first housing at a position located more inward than the axial end of the cylinder head so that the cylinder head is not required to be formed with an axial extension, and is enabled to support the auxiliary device and a bearing for the camshaft extension in a highly stable manner.