This invention describes a variable valve timing mechanism which may be fitted to an internal combustion engine to provide precise control over timing of the valve opening and closing events of the camshaft relative to the crankshaft. Various methods for its application are described to provide settable valve timing at either predetermined angle selected by the operator, or automatic variable valve timing as governed by parameters of the operating engine. Said mechanism comprised of oppositely located idler rollers, whereas not bound to a single yoke or carrier, are driven by a cam to achieve independent movement of the rollers, which bear against both tension and slack sides of the belt between the crankshaft and camshaft pulleys causing predictable and repeatable variation in valve timing. Thus, this invention, whereby coordinated but non-uniform movements of the idler rollers is achieved by the mechanical appurtenances described herein, including a specially developed cardioid cam to actuate said idler rollers, produces precise changes in camshaft phase angle.

An engine variable camshaft timing (VCT) phaser assembly is equipped in an internal combustion engine (ICE) to adjust the rotation of the engine's camshaft relative to the engine's crankshaft. The adjustments advance and retard the opening and closing movements of the engine's intake and exhaust valves. An electric motor and a planetary gear set work together amid use of the VCT phaser assembly. The planetary gear set can include two or more ring gears, planet gears, and a sun gear. A backlash condition sometimes experienced in previous VCTs is minimized in the VCT phaser assembly by one or more springs that urge the planet gears into engagement with the ring gears.

The invention relates to a gear device (101) for a motor vehicle, as is used, for example, for adjusting a camshaft in a combustion engine in order to influence the phase angle between crankshaft and camshaft. Such gear devices (101) have to be constructed compactly and also have to have high resistance to wear, in particular on reaching end stops during adjustment of the phase angle. For this purpose, the gear device (101) has hydraulic end stop damping by the drive unit (103) and the output unit (105) having communicating cavities (113, 115).

A valve assembly that can be employed in a variable camshaft timing (VCT) phaser assembly. The valve assembly includes a metal sleeve and a check valve. The check valve, in an implementation, has an integral construction with the metal sleeve. The integral construction has multiple designs, one of which includes an overmolded construction of the check valve with the metal sleeve. The valve assembly can also include a valve housing which, in the implementation of the VCT phaser assembly, is a center bolt.

Systems and methods for operating an engine with deactivating and non-deactivating valves is presented. In one example, the engine may include non-deactivating intake valves, deactivating intake valves, and only non-deactivating exhaust valves. The non-deactivating exhaust valves may operate to open and close during an engine cycle while deactivating intake valves remain closed during the engine cycle to prevent air flow through selected engine cylinders.

An oil pressure actuated or torsion assisted phaser with a lock pin that has a position which shuts off communication between the advance and retard chambers and the front cam bearing and/or oil control valve, effectively acting as a shutoff valve and preventing leakage of oil from the advance and retard chambers. The prevention of leakage maintains oil in the phaser after engine shutdown. Additionally, by shutting off communication between the advance and retard chambers and the oil supply, the side load on the lock pin from the oil pressure torque on the rotor vanes during unlocking of the lock pin can be reduced or eliminated.

A phaser which has an offset or remote pilot valve added to the hydraulic circuit to manage a hydraulic detent switching function, in order to provide a mid-position lock for cold starts of the engine, either during cranking or prior to complete engine shutdown. The mid-position locking of the phaser positions the cam at an optimum position for cold restarts of the engine.

An Oldham coupling includes an engagement arm. At least either a driving-side rotor or an input gear has an engagement portion engaged with the engagement arm and is connected to the Oldham coupling. The engagement arm has a pair of arm flat surface portions perpendicular to a rotational direction of the driving-side rotor. The engagement portion has a pair of engagement flat surface portions that the arm flat surface portions face in a sliding contact manner. Each arm flat surface portion is, within a range where the arm flat surface portion slides against a facing engagement flat surface portion, always in contact with an overlapping portion of the engagement flat surface portion with the arm flat surface portion when viewed from a direction perpendicular to a sliding direction of the Oldham coupling and in which the arm flat surface portion and the engagement flat surface portion overlap each other.

The disclosure relates to a camshaft adjusting device with a dry belt, a central valve arranged within a camshaft adjuster, and an actuator acting on the central valve. An oil-tight wet space is formed by the camshaft adjuster and the actuator or a component supporting the actuator, and oil present in the wet space can be evacuated by means of an oil path. A portion of this oil path extends axially through the output element of the camshaft adjuster. This oil path can pass the end-side contact face between the output element and camshaft, opening out into an axial bore of the camshaft which is distanced radially from the axis of rotation of the camshaft adjusting device. The axial bore runs beneath an oil feed connection formed on the outer surface of the camshaft for feeding oil to the central valve.

Intake and exhaust cam shafts are disposed a cylinder head in a vertical direction. The cylinder head comprises a first through hole and a second through hole. The first through hole penetrates an upper surface deck from a deck surface towards a lower surface of the cylinder head. The deck surface is a surface constituting an upper surface deck of the cylinder head. The second through hole opens to a side surface of the cylinder head in which cam pulleys of intake and exhaust cam shafts are provided. The second through hole penetrates the upper surface deck along an axial direction of the intake and exhaust cam shafts. The second through hole is positioned vertically below an opening in the deck surface of the first through hole.