Systems, devices, and methods are disclosed that during cylinder deactivation, including skipfire, at low engines speeds and low engine loads maintain adequate oil pressure of valvetrain components or hardware required for CDA and/or skipfire operation.

Systems and methods for operating an engine with deactivating valves are presented. In one example, a groove in a camshaft controls oil flow to a valve operator that selectively activates and deactivates a poppet valve of a cylinder. The groove moves with the camshaft so that oil delivery to the valve operator is timed properly to deactivate and reactivate the cylinder.

A camshaft adjusting device having improved lubricant management including adjusting gearing for adjusting the angular position of a camshaft is proposed, the adjusting gearing having an input shaft, which can be coupled to a crankshaft, an output shaft, which can be coupled to the camshaft and an adjusting shaft, which can be coupled to an actuator. The adjusting gearing defines a rotational axis and the gearing forms a gearing interior, in which the input shaft, the output shaft and the adjusting shaft are operatively interconnected. The camshaft adjusting device has a lubricant supply for supplying the gearing interior with a lubricant and the lubricant supply is designed to form a lubricant sump in the gearing interior, the sump being radially outwards situated relative to the rotational axis.

A cam follower assembly is provided including an improved lubricant flowpath. The assembly includes a generally cylindrical housing including an annular groove adapted to be in communication with a lubricant gallery in an engine block or cylinder head. An axial end of the housing includes skirt portions including openings, and one of the skirt portions includes a first recessed section indented from an outer lateral surface of the housing and extending axially between the annular groove and a respective one of the openings. A pin is mounted in the openings of the skirt portions and has a second recessed section indented from an outer lateral surface of the pin that extends to at least one of the ends of the pin. The second recessed section is in communication with the first recessed section, and a cam roller supported on the pin.

A valve cover module includes a unitary cover and carrier made of a carbon fiber composite. The unitary cover and carrier has a lower side with a peripheral edge for attaching to a cylinder head. The lower side of the unitary cover and carrier also has a series of cavities interconnected with aligned apertures defining bearing surfaces. A plurality of cam lobes is disposed in the series of cavities. Also, the valve cover module includes a camshaft rotatable on the bearing surfaces and extending through the aligned apertures to couple with the cam lobes.

The invention relates to a method for producing a spray channel (4) on a shaft tube (1), via which with finished shaft tube (1) fluid (5) can be output from within the shaft tube (1) to the outside, having the steps introducing at least one through-opening (7) with a diameter D.sub.1≥1.5 mm into the shaft tube (1), arranging at least one additional element (8) in or on the through-opening (7) in such a manner that the spray channel (4) is at least partly formed by the additional element (8).

The invention also relates to a camshaft (2) having a shaft tube (1) produced with such a method.

A four-stroke engine includes an oil tank, a crankshaft chamber, a distribution chamber, a rocker chamber, a combustion chamber, and a lubricating system. The oil tank is communicated with the crankshaft chamber through an oil supply channel. The four-stroke engine further comprises a cam and a transmission mechanism connected between the cam and a crankshaft of the crankshaft chamber in a matched manner. The cam is matched with a rocker of the rocker chamber and located above the combustion chamber.

An engine includes a cylinder head including a first oil path and a second oil path. The cylinder head includes a valve gear including a first support and a second support that support a rocker shaft. The first support includes, on its outer surface, a first constriction located at an inlet of a connection-switching third oil path and connected to the first oil path, and a second constriction connected to the second oil path. The second support includes, on its outer surface, a third constriction connected to the first oil path, and a fourth constriction located at an inlet of a lubrication fourth oil path and connected to the second oil path.

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.

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.