Provided is an internal combustion engine having an oil circulating structure wherein oil used to lubricate valve operating members in the cylinder head drops onto an oil pan, and the oil accumulated therein is drawn up to the cylinder head again. Each on corners of the squire bottom face inside the cylinder head of the internal combustion engine, an oil dropping hole is provided to allow the oil used to lubricate valve operating members to flow thereinto. Also provided is an oil channel communicating with one or more of the oil dropping hole at the bottom thereof to guide the oil toward the driving gear transmitting the driving force of the engine.

Provided is an internal combustion engine having an oil circulating structure wherein oil used to lubricate valve operating members in the cylinder head drops onto an oil pan, and the oil accumulated therein is drawn up to the cylinder head again. Each on corners of the squire bottom face inside the cylinder head of the internal combustion engine, an oil dropping hole is provided to allow the oil used to lubricate valve operating members to flow thereinto. Also provided is an oil channel communicating with one or more of the oil dropping hole at the bottom thereof to guide the oil toward the driving gear transmitting the driving force of the engine.

There is provided a lubricating structure for a power transmission mechanism in which a crankshaft is coupled to a piston disposed in a cylinder bore and in which power is transmitted from the crankshaft to a camshaft. The lubricating structure includes: an idler gear that is configured to transmit power from the crankshaft to the camshaft; and an idler gear shaft that supports the idler gear via a bearing. One end portion of the idler gear shaft protrudes into the cylinder bore, and an oil passage configured to guide oil from the cylinder bore to the bearing is formed in the idler gear shaft.

A continuous variable valve duration apparatus includes a cam unit, a cam formed on the cam unit, a camshaft inserted into the cam, a guide bracket, a guide shaft mounted on the guide bracket and disposed perpendicular to the camshaft, wherein a guide screw thread is formed on the guide shaft, a wheel housing disposed within the guide bracket, an inner wheel rotatably inserted into the wheel housing and movable perpendicular to the camshaft, a worm wheel disposed within the wheel housing, wherein an inner screw thread configured to engage with the guide screw thread is formed inside the worm wheel and an outer screw thread is formed on the worm wheel, a control shaft, a control worm formed on the control shaft, and a wheel elastic portion mounted to the wheel housing.

Systems and methods for intermittent supply of lubricating oil to a tip of a rocker arm assembly. In one embodiment, a lubricating oil may be selectively to a tip of a rocker arm via oil channels aligned only during opening of a valve coupled to the tip.

Systems and methods for intermittent supply of lubricating oil to a tip of a rocker arm assembly. In one embodiment, a lubricating oil may be selectively to a tip of a rocker arm via oil channels aligned only during opening of a valve coupled to the tip.

A valve actuation system for an engine includes a rotatable camshaft, an injector actuation linkage, and a valve actuation linkage. The valve actuation linkage includes a valve lifter, a valve pushrod, and a rocker arm. At least one of a rocker arm center plane defined by the valve rocker arm or a lifter roller center plane defined by the valve lifter is spaced an offset distance from a pushrod axis, providing an increased contact width between an injector roller in the injector actuation linkage and one of a plurality of cam lobes of the camshaft. The valve lifter includes a fork defining a center plane spaced an offset distance from a center axis of the valve lifter. A rocker arm includes a screw bore offset relative to a rocker arm center plane.

A valve actuation system for an engine includes a rotatable camshaft, an injector actuation linkage, and a valve actuation linkage. The valve actuation linkage includes a valve lifter, a valve pushrod, and a rocker arm. At least one of a rocker arm center plane defined by the valve rocker arm or a lifter roller center plane defined by the valve lifter is spaced an offset distance from a pushrod axis, providing an increased contact width between an injector roller in the injector actuation linkage and one of a plurality of cam lobes of the camshaft. The valve lifter includes a fork defining a center plane spaced an offset distance from a center axis of the valve lifter. A rocker arm includes a screw bore offset relative to a rocker arm center plane.

A valve gear has a cam shaft with a firing cam and a braking cam. A first cam follower is allocated to the firing cam with the first cam follower being provided in a firing operation for actuating a gas exchange valve. A second cam follower is allocated to the braking cam with the second cam follower being provided in a braking operation for actuating the gas exchange valve. A changeover device switches between the operations and has a tilting lever mount having a pivotably mounted mounting element on which a tilting lever belonging to the first cam follower and a tilting lever belonging to the second cam follower are pivotably mounted. The tilting lever mount has two mounting screws respectively having a ball head and the ball heads each form a ball joint together with a ball head receiver of the allocated tilting lever.

A valve gear has a cam shaft with a firing cam and a braking cam. A first cam follower is allocated to the firing cam with the first cam follower being provided in a firing operation for actuating a gas exchange valve. A second cam follower is allocated to the braking cam with the second cam follower being provided in a braking operation for actuating the gas exchange valve. A changeover device switches between the operations and has a tilting lever mount having a pivotably mounted mounting element on which a tilting lever belonging to the first cam follower and a tilting lever belonging to the second cam follower are pivotably mounted. The tilting lever mount has two mounting screws respectively having a ball head and the ball heads each form a ball joint together with a ball head receiver of the allocated tilting lever.