An internal combustion engine includes: a cylinder head (3); a combustion chamber recess (15) formed in the cylinder head; an intake passage (16) and an exhaust passage (17) formed in the cylinder head and communicating with the combustion chamber recess; a head oil passage (80) formed in the cylinder head, and having a first end (81A) communicating with an oil pump (62) and a second end (81B) opening out at a sliding contact surface of a valve actuating mechanism (23) provided in the cylinder head; and an oil jacket (84) formed in the cylinder head in a path of the head oil passage so as to at least partly surround the exhaust passage.

A continuous variable valve duration apparatus may include: a camshaft; first and second cam portions on which a cam is formed respectively; first and second inner brackets transmitting rotation of the camshaft to the first and second cam portions respectively; a slider housing in which the first and the second inner brackets are rotatably inserted; first and second guiding portions formed on the slider housing; a control shaft parallel to the camshaft; a control rod eccentrically formed on the control shaft; a guide head on which a head guiding portion and a head hole are formed; a cam cap supporting the control shaft; a cam cap guiding portion mounted to the cam cap; and a control portion selectively rotating the control shaft such that the slider housing is moved along the cam cap guiding portion.

A valve train for a reciprocating piston internal combustion engine with a transmission element in the form of a rocker arm (1) or pivot arm that can be actuated, on one hand, at least indirectly by a cam of a camshaft and is in active connection, on the other hand, through an intermediate connection of a valve bridge (4), with gas-exchange valves (7, 8). The valve bridge (4) has hydraulic valve lash compensation elements (HVAs) allocated to each gas-exchange valve (7, 8).

A spacer for a valvetrain in an engine system includes a spacer body defining a spacer axis and including a through-bore extending from a first axial end to a second axial end, an outer arcuate surface, and an inner arcuate surface having an oil feed inlet. The spacer further includes an orientation element extending from the spacer body and defining an orientation axis transverse to the spacer axis, and including an inner orientation surface and an outer orientation surface. The spacer further includes an oil application structure defining a structure axis oriented transverse to both the spacer axis and the orientation axis, and including a plurality of oil spray channels, each respective one of the plurality of oil spray channels including an oil outlet at a termination point and being fluidly connected to the oil feed inlet.

A crankcase assembly for an engine is provided. The crankcase assembly includes a crankcase comprising a crank sump, the crank sump including a primary sump volume and a secondary sump volume, one or more crankcase oil catchers, the crankcase oil catchers comprising one or more surfaces configured to catch dispersed oil in the crankcase and direct the oil along the surfaces of the crankcase oil catcher away from a crankcase casing wall and towards the crank sump, wherein the crankcase oil catchers are provided above a crankshaft and below an associated piston of the engine, and one or more guides configured to collect oil captured by the crankcase oil catchers and guide the oil to the primary sump volume.

A oil supply structure of an internal combustion engine, includes: an oil flowing path which is formed to extend along a camshaft vertically above at least one of intake and exhaust camshafts (3a, 3b) of the internal combustion engine, and in which oil flows; an oil supply portion provided on one end side of the oil flowing path, and supplying oil to the oil flowing path; and oil ejection holes aligned along the oil flowing path, provided to be opened vertically downward, and through which the oil of the oil flowing path is ejected toward the camshaft, wherein, in the oil flowing path, a partitioning portion, which extends along the oil ejection holes toward the other end side opposite to the oil supply portion from one end side, and partitions the inside of the oil flowing path, is provided.

A spacer for a valvetrain in an engine system includes a spacer body defining a spacer axis extending between a first axial spacer body end and a second axial spacer body end, and including an outer peripheral surface, a circumferentially extending inner peripheral surface forming a through-bore, an oil spray port extending from the inner peripheral surface to the outer peripheral surface, and a circumferentially extending fluid groove formed in the inner peripheral surface and extending to the oil spray port. Related valvetrain and rocker arm assembly apparatus is also disclosed.

A continuous variable valve duration apparatus may include: a camshaft; first and second cam portions on which a cam is formed respectively; first and second inner brackets transmitting rotation of the camshaft to the first and second cam portions respectively; a slider housing in which the first and the second inner brackets are rotatably inserted; first and second guiding portions formed on the slider housing; a control shaft parallel to the camshaft; a control rod eccentrically formed on the control shaft; a guide head on which a head guiding portion and a head hole are formed; a cam cap supporting the control shaft; a cam cap guiding portion mounted to the cam cap; and a control portion selectively rotating the control shaft such that the slider housing is moved along the cam cap guiding portion.

A continuous variable valve duration apparatus may include: a camshaft; first and second cam portions on which a cam is formed respectively; first and second inner brackets transmitting rotation of the camshaft to the first and second cam portions respectively; a slider housing in which the first and the second inner brackets are rotatably inserted; first and second guiding portions formed on the slider housing; a control shaft parallel to the camshaft; a control rod eccentrically formed on the control shaft; a positioning protrusion connected to the control shaft; a guide head on which a head guiding portion and a head hole are formed; a cam cap supporting rotations of the first and the second cam portions and guiding movement of the slider housing, a control portion selectively rotating the control shaft; and a stopper unit limiting movement of the positioning protrusion.

A continuous variable valve duration apparatus may include: a camshaft; first and second cam portions on which a cam is formed respectively; first and second inner brackets transmitting rotation of the camshaft to the first and second cam portions respectively; a slider housing in which the first and the second inner brackets are rotatably inserted; first and second guiding portions formed on the slider housing; a cam cap on which a cam cap guide contacting the second guiding portion is formed; a control shaft parallel to the camshaft; a control rod eccentrically formed on the control shaft; a guide head on which a head guiding portion and a head hole are formed; a control portion selectively rotating the control shaft; and a stopper limiting movement of the guide head. The head guiding portion is connected to the first guiding portion, and the control rod is inserted into the head hole.