Abstract: A switchable valve train assembly including a carrier housing defining a hydraulic circuit, a supply assembly, a plurality of rocker shafts, a plurality of separators, and a plurality of rocker arm assemblies is provided. Each one of the plurality of separators divides the rocker shafts into (1) a first chamber extending between a first chamber axial end and the separator, and (2) a second chamber extending between a second chamber axial end and the separator. The plurality of separators each include an orifice defined between the first chamber and the second chamber that provides fluid connection between the first chamber and the second chamber. Locking assemblies of the rocker arm assemblies are selectively actuated based on the supply assembly. The separators ensure that hydraulic fluid within the hydraulic fluid is de-aerated and that the second chambers remain primed with hydraulic fluid for faster actuation of the locking assemblies.

Abstract: A lash adjuster includes a bottomed cylindrical body and a cylindrical plunger reciprocably inserted into the body and having a bottom wall and a peripheral wall. The plunger has a low-pressure chamber. The peripheral wall of the plunger includes an annular band portion abutting against an upper part of a peripheral wall of the body. The peripheral wall of the plunger has a plurality of plunger oil holes located below the band portion. The plunger oil holes include respective lower ends defining a level of the oil stored in the low-pressure chamber. The plurality of plunger oil holes are located at a common height position of the peripheral wall of the plunger coming close to the band portion.

Abstract: A camshaft may include a shaft as well as a sliding element that is disposed on the shaft such that the sliding element is axially displaceable along a shaft axis. The shaft may comprise an external tooth for transmitting torque between the shaft and the sliding element. The external tooth may engage a mating tooth geometry formed in a passage of the sliding element. The sliding element on its axial end faces may comprise bearing collars that with the shaft form radial supporting bearings of the sliding element on the shaft. Further, the shaft may comprise cylindrical bearing portions for forming the radial supporting bearings, wherein the bearing portions can be configured with a diameter that is smaller than a diameter circumscribed by tips of the mating tooth geometry that protrude into the passage of the sliding element.

Abstract: Methods and systems are provided for adjusting an oil pressure supplied to an engine and a variable cam timing (VCT) responsive to a condition of the VCT system. In one example, a method may include adjusting the oil pressure based on engine speed, engine load, and engine oil temperature, and responsive to a request to shift the VCT system during specific engine operating conditions, increasing the oil pressure to an upper threshold oil pressure for the duration of the shift.

Abstract: The cam follower roller device providing a tappet body extending along an axis, an insert mounted in the tappet body, a pin mounted at least on the insert and a roller mounted on the pin. The device further provides a retaining washer mounted into a bore of the tappet body so as to axially retain the insert inside the tappet body. The tappet body provides retention means, cooperating with the washer to axially retain the washer relative to the tappet body. The retaining washer is axially interposed between the insert and the retention means.

Abstract: An oil separation device of an internal combustion engine includes a gas liquid separation chamber defined by a head cover of the engine, a gas introduction passage connected to a first end of the gas liquid separation chamber at an angle to the first direction, a gas inlet formed in an end of the gas introduction passage remote from the gas liquid separation chamber, and a gas outlet formed in a second end of the gas liquid separation chamber. Oil splashed from a valve actuating chamber of the engine is prevented from entering the oil separation device, and oil mist can be effectively separated from blow by gas.

Abstract: A combustion engine includes an engine valve arranged to selectively open/close a combustion chamber of the engine, a cylinder head adjacent the combustion chamber, arranged to guide a valve stem of the engine valve, the engine valve being axially displaceable relative to the cylinder head between the combustion chamber closed position and the combustion chamber fully opened position, and a valve spring retainer connected to the valve stem. The valve spring retainer partly delimits a gas spring volume, which is in fluid communication with an adjacent gas volume via a port when the engine valve is in the combustion chamber closed position, and which is separated from the adjacent gas volume when the engine valve is in the combustion chamber fully open position, the port being open during at least 25% of the maximal stroke of the engine valve and being closed due to a displacement of the engine valve.

Abstract: A valvetrain includes a rocker arm assembly having an electromagnetic latch housed in a chamber formed by a rocker arm. The chamber may be a retrofit hydraulic chamber. A flux shifting bi-stable latch provides a sufficiently compact design. Isolation of the magnetic elements within the rocker arm chamber may provide protection from metal particles carried by oil in an operating environment for the rocker arm assembly. Wiring connections to the rocker arms may be made through spring posts on the rocker arms. Connection to the rocker arms may be made with springs that can endure the rapid motion induced by the rocker arms. A wiring harness for the rocker arms may attach to hydraulic lash adjusters of the rocker arm assemblies. The rocker arm assemblies and their wiring may be formed into a unitary module that facilitates installation.

Abstract: A method for controlling a high-pressure pump for the injection of fuel into a combustion engine, the high-pressure pump being connected to a camshaft of the combustion engine, wherein the high-pressure pump is controlled in a camshaft-synchronous manner by ascertaining an angular offset between the flank positions of a camshaft pulse-generating wheel and a predefinable point above the bottom dead center of a cam of the high-pressure pump on the camshaft.

Abstract: A method of phasing the opening and closing of internal combustion engine intake and exhaust valves relative to the rotation of the crankshaft is based upon changes in engine speed, engine load and ambient relative humidity. During certain conditions of higher humidity, in order to maintain good combustion stability and thus overall engine operation, it is necessary to reduce intake and exhaust valve overlap by adjusting the phase of the intake and exhaust camshafts. This is achieved by utilizing a set of cam position reference values and constraints based upon engine speed, engine load and humidity that are contained in lookup tables that adjust and limit cam position and valve overlap. Generally speaking, in order to maintain optimum engine performance, intake and exhaust valve overlap is reduced with higher ambient humidity and vice versa.

Abstract: Methods and systems are provided for adjusting engine operating conditions for reduction of NOx emissions. In one example, immediately after a fuel shut-off event, in response to an oxygen content of an exhaust catalyst being higher than a threshold, manifold charge cooling may be increased by increasing the portion of fuel delivered to the engine via manifold injection relative to the portion to fuel delivered via one or more of port and direct injection. By increasing manifold cooling, NOx production may be reduced.

Abstract: A cam phaser includes a stator, a rotor positioned in the stator, a cover plate positioned on a first side of the stator, a locking cover positioned on a second side of the stator, a locking pin assembly configured to selectively lock the rotor in a position relative to the stator, a plurality of aligned first openings which extend through the stator, the cover plate, and the locking cover, a plurality of fasteners respectively inserted in the plurality of aligned first openings, and a plurality of aligned central openings forming a throughbore. The locking cover has a body made from sheet metal having a first axial side, a second axial side, a plurality of the first openings extending from the first axial side to the second axial aide, and a second opening extending from the first axial side to the second axial side. The body has a web portion and a plurality of reinforcing portions which are thicker than the web portion.

Abstract: A variable valve mechanism of an internal combustion engine includes an outer arm, an inner arm, a switching device that switches between a coupled state and a non-coupled state, and a lost motion spring. The lost motion spring has an extending portion extending from the outside of the space to the inside of the space. The extending portion has a contact portion that is in contact with the inner arm in the space and being configured to swing in conjunction with swinging of the inner arm. A through-hole is formed in a vertically intermediate portion of the outer arm such that connecting portions are provided at vertically opposite sides of the through-hole, and a portion of the extending portion, a swinging amount of which is smaller than that of the contact portion, passes through the through-hole that allows the portion to swing therein.

Abstract: A hydraulic control valve allows increased flexibility of port layout without requiring high dimensional accuracy. The hydraulic control valve includes a cylindrical valve body having, at a cylindrical shaft portion, retard and advance ports and reintroduction ports, and a spool valve provided slidably in an axial direction in the valve body and permitting switching between supply/discharge of working fluid to/from retard and advance hydraulic chambers through land portions. The control valve further includes a cylindrical sleeve formed with synthetic resin material and fixed to an outer peripheral surface of the cylindrical shaft portion, and an actuator that moves the spool valve in an axial direction. The sleeve has, at a peripheral wall thereof, retard and advance oil passage holes communicating with retard and advance ports, and has, on an inner peripheral surface thereof, communication grooves communicating with the reintroduction ports.

Abstract: An internal combustion engine for a motorcycle includes a rear cylinder head, the rear cylinder head being provided with a camshaft, an exhaust rocker arm rocked by the camshaft, an engine valve closed/opened by being push-pressed by the exhaust rocker arm, and a rocker arm shaft swingably supporting the exhaust rocker arm. In the internal combustion engine for the motorcycle, the rear cylinder head is provided separately from a holder member, the holder member being provided adjacently to the rear cylinder head, the camshaft is rotatably supported by the holder member, and the holder member is provided with right and left rear side walls and internal combustion engine supporting portions, the right and left rear side walls supporting the rocker arm shaft, the internal combustion engine supporting portion being supported by a vehicle body frame.

Abstract: 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.

Abstract: A control valve is configured to reduce an axial length of a device as much as possible, thereby improving its mountability. The valve is equipped with a valve body functioning as a cam bolt for connecting a vane rotor to one end of a camshaft, a sleeve fixed to an inner peripheral surface of the valve body, and a spool valve element axially slidably housed in the sleeve for switching between supply and discharge of working fluid to and from each of a phase-retard working chamber and a phase-advance working chamber. The valve body has a male screw part formed on an outer peripheral surface and screwed into a female screw part formed in a cam bolt hole. The position of formation of the male screw part and the position of the spool valve element are arranged to overlap with each other in an axial cross-section.

Abstract: A monolithic rocker arm component includes a first lateral wall defining a first aperture and a first mass reducing feature, an opposing second wall defining a second aperture and a second mass reducing feature, a pushrod receiving member that bridges the first lateral wall and the second lateral wall at a first end of the rocker arm, and a tongue element that bridges the first lateral wall and the second lateral wall at a second end of the rocker arm. The pushrod receiving member routes oil from the first towards the second end. The monolithic rocker arm may have one or more internal regions having lattice structures. Methods for additive manufacturing the monolithic rocker component are also provided.

Abstract: The present disclosure provides a hydraulic control valve for a valve timing adjusting device of an engine. The valve timing adjusting device has a hydraulic control valve; a housing; a rotor installed in the housing and having vanes forming advance, retard and locking chambers, respectively; and a locking pin member elastically installed at the locking chamber. In particular, the hydraulic control valve includes: a valve body connected to the camshaft and having ports and a spool space; an outer spool elastically installed in the spool space and having distribution ports selectively communicated with or disconnected to the ports of the valve body; and an inner spool that is integrally coupled to the outer spool and forms a supply passage connected to a working fluid pump and a drain passage connected to a drain tank together.

Abstract: A valve device for an internal combustion engine (1) includes a camshaft (16), a cam (17), a control shaft (15), an input arm (14), a first rocker arm (13a), a second rocker arm (13b), a first valve (603a), a second valve (603b), and a slider (18). The input arm (14) is configured such that a cam torque of the cam (17) is transmitted thereto. The slider (18) is configured to allow the input arm (14) to be supported by the control shaft (15). The slider (18) is configured to support the first rocker arm (13a) in a power transmittable manner such that the cam torque transmitted to the input arm (14) is transmitted to the first rocker arm (13a). The slider (18) includes a torsion portion (23) configured to connect the first rocker arm (13a) with the second rocker arm (13b) such that the cam torque transmitted to the first rocker arm (13a) is transmitted to the second rocker arm (13b) via the torsion portion (23).