Abstract: A camshaft may include a shaft on which at least one sliding element is received in such a way as to be axially displaceable along a shaft axis. The shaft may comprise an external longitudinal spline structure that meshes with an internal spline structure of a passage in the sliding element such that the sliding element is arranged in a rotationally fixed manner on the shaft. The sliding element, on its axial end faces, may comprise guiding portions by way of which the sliding element is guided on the shaft to minimize an axial offset of the sliding element. Further, guiding sleeves against which the guiding portions of the sliding element are supported may be received on the shaft.

Abstract: A rocker arm includes an outer arm; an inner arm which selectively pivots relative to the outer arm; and a latching arrangement which switches the rocker arm between a coupled state and a decoupled state. The latching arrangement includes a connecting bore which is terminated by a connecting bore floor; an oil supply bore which opens into the connecting bore through the connecting bore floor; a lock pin bore which opens into the connecting bore through the connecting bore floor; a lock pin within the lock pin bore where the lock pin prevents the inner arm from pivoting in the coupled state and where the lock pin permits the inner arm to pivot in the coupled state; and a retainer within the connecting bore which defines a chamber within the connecting bore which provides fluid communication between the oil supply bore and the lock pin bore.

Abstract: A camshaft for a multiple-cylinder internal combustion engine may include a sliding element comprising at least two cam elements, as well as a splined shaft that extends in an axial direction and on which the sliding element is received. The sliding element may comprise an internal spline system that interacts with an external spline system of the splined shaft such that the sliding element is seated fixedly on the splined shaft so as to rotate with the splined shaft. The sliding element may be received on the splined shaft such that the sliding element can, at least initially, be displaced axially. For axially-fixing the sliding element to the splined shaft, the sliding element may include a positively locking connection that is configured in the axial direction and is produced by way of at least one calked connection between the sliding element and the splined shaft. It should be understood that many camshafts include more than one sliding element.

Abstract: A camshaft is equipped with an inner shaft which is arranged rotatably inside a cylindrical outer shaft. Further, in the inner shaft, a plurality of pin holes extend along diametrical directions thereof, and are disposed at intervals along the axial direction of the inner shaft. The directions in which adjacent pin holes extend are arranged at angles obtained by dividing 360 degrees by the number of cylinders. The inner shaft and the inner cams are fixed in a state in which large diameter portions of pins, each of which is provided with a small diameter portion and a large diameter portion, are press-fitted through insertion holes of the inner cams and notches of the outer shaft, and are press-fitted into the pin holes.

Abstract: A roller tappet includes a housing, and the housing includes a first housing element and a second housing element. The first housing element has a receiving region configured to receive a roller of the roller tappet, and the second housing element is separate from the first housing element and is forged. The first housing element may be formed from metal sheet.

Abstract: A cam follower is provided having a tappet that includes a cylindrical outer surface centered on a longitudinal axis and adapted to slide in a housing surrounding the tappet, a pin extending between two opposite ends along a transverse axis perpendicular to the longitudinal axis, a roller element movable in rotation relative to the pin around the transverse axis and adapted to roll on a cam, and lubrication channels for lubricating the pin and the roller. The cam follower further provides a support element mounted in the tappet and supporting the pin, and the lubrication channels include at least one pair of consecutive channels formed through the tappet and the support element. The invention also provides an injection pump and a valve actuator for a motor vehicle, each having such a cam follower. The invention finally provides a method for manufacturing such a cam follower.

Abstract: A compact power unit with a sufficient clearance between a stud bolt and a fixing shaft of a cam chain tensioner pivot mechanism for supporting a cam chain tensioner guide. The power unit including a crankshaft, a stud bolt configured to fix a crankcase and a cylinder body to each other, a cam chain, a cam chain tensioner mechanism including a cam chain tensioner guide, and a cam chain tensioner pivot mechanism including a pivot plate, a fixing shaft, and a swinging shaft, the fixing shaft and the swinging shaft are arranged so as to straddle the axis of the stud bolt as viewed in the axial direction of the crankshaft.

Abstract: A hydraulically operated camshaft phasing mechanism has two lock pins. One of the lock pins engages at an intermediate position and an end lock pin engages near one of the stops at the end of the phaser range of authority. At least one of the locking pins, preferably the end lock pin, when the vane is at an end stop position, is engaged by oil pressure and spring loaded to release when the oil pressure side of the end lock pin is vented.

Abstract: A rocker arm assembly for a valvetrain having a valve, a lash adjuster, and a camshaft lobe. The rocker arm assembly includes a shaft, a bearing rotatably supported by the shaft for engaging the lobe, and a rocker arm. The rocker arm has a pad for engaging the valve, and a socket for engaging the lash adjuster. A pair of walls are disposed between the pad and socket and define a valley for accommodating the shaft. A pair of upwardly-opening arc-shaped bearing surfaces are disposed longitudinally between the pad and the socket and are spaced laterally from each other. The bearing surfaces rotatably support the shaft when the bearing engages the lobe. A pair of retention elements extend from the walls into the valley above the bearing surfaces such that the shaft is prevented from moving out of the valley in absence of engagement between the bearing and the lobe.

Abstract: A valve timing control device 1 has a lock mechanism 30 which limits a relative rotation of a vane rotor 20 with respect to a housing 10 by engaging a lock plate 31 that is accommodated slidably in a radial direction with an engagement groove 32 of the vane rotor 20 by biasing force of a spring 33 in the housing 10. The lock plate 31 is provided with a plurality of penetrating holes 35 which are opened on a circumferential direction side surface of the lock plate 31.

Abstract: A combustion engine includes a cylinder head including a controllable engine valve configured to open/close a combustion chamber in the combustion engine, a valve actuator operatively connected with and configured to displace the engine valve, and a closed pressure fluid circuit, wherein the valve actuator is arranged in the closed pressure fluid circuit. The combustion engine includes a cylinder head chamber that is included in the closed pressure fluid circuit and that is delimited by the cylinder head and a cylinder head mantle, by the valve actuator including a pneumatic pressure fluid circuit with an outlet opening that is in fluid communication with the cylinder head chamber, and by the cylinder head chamber including a hydraulic liquid drainage valve, wherein a drainage conduit stretches from the hydraulic liquid drainage valve to a hydraulic liquid vessel of the combustion engine for draining hydraulic liquid accumulated in the cylinder head chamber.

Abstract: Methods and systems are provided for adjusting a cylinder deactivation pattern to improve camshaft phasing. In response to a request for actuating a camshaft phaser of a variable cam timing device, a cylinder deactivation pattern is adjusted by reactivating cylinders that were deactivated while deactivating other cylinders that were active, while maintaining a total number of deactivated/active cylinders. Cylinders are selected for reactivation or deactivation based on their individual camshaft torsion signatures so that sufficient cam torque is generated to actuate the phaser and provide the requested phasing.

Abstract: A switchable rocker arm for valve deactivation is provided for a valve train of an internal combustion engine. The switchable rocker arm includes a valve side lever assembly, a cam side lever assembly, and a hydraulically actuated coupling assembly. The valve side lever assembly includes a first housing with a first rocker shaft bore. The cam side lever assembly includes a second housing with a first arm with a second rocker shaft bore and a second arm with a third rocker shaft bore. The first and second arms extend along opposed longitudinal sides of the cam side lever assembly such that the first, second and third rocker shaft bores are axially aligned. The coupling assembly is arranged at an end furthest away from a pivot axis for minimal loading and provides locking and unlocking of the switchable rocker arm to achieve full valve lift and no valve lift modes, respectively.

Abstract: A camshaft adjuster for adjusting the angle of rotation of a camshaft, including a stator which can be driven by a crankshaft of an internal combustion engine and which has a plurality of radially inwardly protruding stator lands, and a rotor having a plurality of vanes projecting radially outwards from a radially inner ring, and an annular gap which is provided between the stator and the rotor and which is divided by a plurality of stator lands into working chambers which are in turn divided by the vanes into pressure chambers acting in opposite directions, wherein the rotor is divided into at least two rotor parts in a dividing plane arranged perpendicular to an axis of rotation of the camshaft adjuster, wherein the dividing plane of the rotor intersects at least one pressure medium line, and the pressure chambers acting in a first direction are separated from the pressure chambers acting in a second direction by at least one seal between a first and a second end face of the two rotor parts is provided.

Abstract: A system and method for diagnosing malfunctions in a variable valve actuation device. The method uses a rocker arm assembly with a hydraulically operated latch for latching together first and second arms of the rocker arm assembly when latched. The rocker arm assembly includes a source of pressurized fluid connected to a hydraulic valve that provides fluid high or low pressure fluid to the hydraulically-operated latch. A control gallery connects the hydraulic valve to the latch. A pressure transducer is positioned within the gallery and is adapted to create a signal indicating the pressure in the gallery. A control unit is coupled to the hydraulic valve and the pressure transducer. The control unit is adapted to sense engine operation parameters, actuate the hydraulic valve, read the signal from the pressure transducer; and identify malfunctions of the rocker arm assembly based upon the signal from the transducer.

Abstract: The present disclosure provides a variable valve duration/variable valve lift system including a camshaft in a first cam with a variable relative phase angle with respect to the camshaft, an inner bracket transmitting rotation of the camshaft, a slider housing, a first rocker arm of which a first end contacts the first cam, a rocker shaft connected to the first rocker arm on which hydraulic lines are formed, solenoid valves configured to selectively supply hydraulic pressure through the hydraulic lines, a position controller configured to selectively change a position of the slider housing according to supplied hydraulic pressure from the solenoid valves, a first bridge connected to a second end of the first rocker arm and to which a first valve is connected, and a first valve lift device disposed within the first bridge for changing valve lift of the first valve according to supplied hydraulic pressure from hydraulic lines.

Abstract: A camshaft adjuster having a drive element, an output element and a spring, wherein the drive element and the output element can rotate relative to each other, wherein the spring is secured by a spring bearing of the drive element and a spring bearing of the output element, wherein the spring supports the relative rotation between the drive element and the output element, wherein the spring bearing has a radius that is larger than the radius of the spring and, as a result of this ratio of the radii, a two-line contact between the spring and the spring bearing is formed.

Abstract: A method for manufacturing a sliding tappet of a valve train of an internal combustion engine may include the steps of: providing a main body; applying a coating at least on a contact surface of the main body configured for contacting an associated cam. The coating may include tungsten carbide and cobalt, and the coating may be applied via high velocity oxygen fuel spraying. The method may further include the step of performing a surface finishing on the coating after the coating is applied.

Abstract: A lifter structure includes a cylindrical member configured to be reciprocally slid in a guide hole of a lifter guide according to rotation of a cam and having an engagement groove and a rotation-preventing member which is separate from the cylindrical member and is disposed so as to face an interior of the guide hole. The rotation-preventing member is inserted into the engagement groove to abut against a groove edge of the engagement groove in a rotation direction of the cylindrical member, thereby preventing the cylindrical member from rotation in the guide hole.

Abstract: A front plate 26 that covers a front end of a housing body is formed from a disk-shaped plate member 41 having in a middle thereof a fitting hole 41a and a cylindrical member 42 having at inner end part thereof a reduced diameter stepped-shaped fitting portion 42a that is fitted to the fitting hole 41a. Stopper portions 44 are formed by crimping a top end side of the fitting portion 42a fitted to the fitting hole 41a, and both of the plate member 41 and the cylindrical member 42 are connected and fixed together by the stopper portions 44 engaging with stopper grooves 43 that are formed at an inner end side hole edge of the fitting hole 41a in a pressed state.