Methods and systems are provided for a phase control apparatus in a variable cam timing (VCT) system of an engine, the phase control apparatus having a locking pin coupled to a rotor vane and engageable with a locking pin recess in the phase control apparatus cover plate. In one example, a method for assembling the phase control apparatus may include positioning respective retarded side surfaces of the rotor vane and the housing in face-sharing contact while positioning respective retarded side surfaces of the locking pin and the locking pin recess in face-sharing contact and maintaining a backlash gap between only the advanced side surfaces of the locking pin recess.

Some examples described herein may involve determining an advance timing window between the valve opening or closing and a designated time that the valve is scheduled to open or close; determining a closing velocity of the valve; monitoring an engine speed of the engine; determining valve lash information based on the advance timing window, the closing velocity, and the engine speed, wherein the valve lash information identifies a magnitude of the valve lash or whether the magnitude of the valve lash associated with the valve satisfies a threshold; and performing an action based on the valve lash information.

A control apparatus of a valve opening/closing timing control mechanism, configured by including driving side and driven side rotating bodies; a stopper unit; and an electric motor,. includes: a phase controller controlling an electric motor to reduce, when a target phase is set, a deviation between the target phase and a current first actual phase and reducing power to be supplied to the electric motor as the deviation decreases; and a control target setting unit setting a first target phase displaced to a side of the first actual phase in an operation direction where the deviation is reduced when the target phase is set to a most retarded or most advanced angle phase, in which the phase controller executes a first phase control of reducing a deviation between the set first target phase and the current first actual phase.

A multiple variable valve lift apparatus may include a moving cam formed of a hollow cylindrical shape, configured to be moveable in an axial direction of a camshaft while being rotated with the camshaft, and forming a plurality of cams implementing a cam guide protrusion device and different valve lifts from each other; an operation device selectively guiding a cam guide protrusion device to move the moving cam in the axial direction of the camshaft; a controller configured for controlling an operation of the operation device; a valve opening/closing device in contact with any one cam among the plurality of cams; a plurality of stopper grooves formed at an external circumference of the camshaft; and a stopper device provided at the moving cam and inserted to the stopper groove to be rotated at a position after the moving cam is moved.

A control device for an internal combustion engine, which can set a VVT (variable valve timing) phase angle so that a reduction in the output of the engine can be suppressed even on a high ground, while ensuring sufficient output, is provided. The control device has a VVT mechanism which changes the opening or closing timing of one or both of an intake valve and an exhaust valve, and comprises: a processor device; a memory device for storing a control program for controlling the processor device; a first sensor for detecting atmospheric pressure; and a second sensor for detecting the amount of air flowing through an intake air flow path. The control program calculates a charging efficiency based on the amount of air detected by the second sensor, calculates a volumetric efficiency from the amount of air and the atmospheric pressure detected by the first sensor, calculates the charging efficiency valve opening timing of the intake valve based on the charging efficiency, calculates the volumetric efficiency valve opening timing of the intake valve based on the volumetric efficiency, and sets the valve opening timing(s) of one or both of the intake valve and the exhaust valve by the variable valve timing mechanism based on one of the charging efficiency valve opening timing and the volumetric efficiency valve opening timing.

An internal combustion engine includes a cylinder head and a valvetrain including a poppet valve, a cam shaft on which is mounted a cam, and a rocker arm assembly. The rocker arm assembly includes a rocker arm and a cam follower configured to engage the cam as the cam shaft rotates. The rocker arm assembly is operative to transmit force from the cam to actuate the valve and includes an electrical device mounted to the rocker arm. A first electrical circuit includes the electrical device and a first conductor mounted to the rocker arm and a second electrical circuit includes a second conductor mounted off the rocker arm. The first and second conductors are inductively coupled to an extent that enables effective power transfer or communication between them. Inductive power transfer avoids the use of wires that could become caught, clipped, or fatigued and consequently short out.

A method, control system, and variable valve timing system are provided for controlling an actuator that can be switched into an on state and an off state with pulse width modulation. The systems and method include controls configured to determine an actual system parameter on a first time schedule and a desired system parameter on a second time schedule. On a third time schedule, a position error difference between the actual system parameter and the desired system parameter is determined. The third time schedule is configured to begin and to determine the position error difference each time that the actual system parameter is determined and each time that the desired system parameter is determined. A desired duty cycle is determined, and a duty cycle command is sent to a pulse width modulation output unit.

A method of operating an internal combustion engine of a type that has a combustion chamber, a moveable valve having a seat formed in the combustion chamber, a camshaft on which a cam is mounted, and a rocker arm assembly having a rocker arm and a cam follower configured to engage the cam as the camshaft rotates. The method includes obtaining rocker arm position data, using the rocker arm position data to obtain camshaft position information, and using the camshaft position information in an engine management operation.

A valvetrain for an internal combustion engine of the type that has a combustion chamber, a moveable valve having a seat formed in the combustion chamber, and a camshaft includes a rocker arm assembly, a pivot providing a fulcrum for a rocker arm of the rocker arm assembly, and a latch assembly. An electrical device mounted to the rocker arm assembly receives power or communicates through a circuit that includes an electrical connection formed by abutment between surfaces of two distinct parts. The rocker arm assembly is operative to move one of the two abutting surfaces relative to the other in response to actuation of the cam follower. Forming an electrical connection through abutting surfaces that are free to undergo relative motion may reduce or eliminate the need to run wires to a mobile portion of the rocker arm assembly.

An exhaust system includes a plurality of cylinders, and each cylinder includes a scavenge exhaust valve and a blowdown exhaust valve. A scavenge path leads from the scavenge exhaust valves and a blowdown path leads from the blowdown exhaust valves. An arrangement activates and deactivates the scavenge exhaust valves and the blowdown exhaust valves. Further included is a cam shaft including a plurality of scavenge cams and a plurality of blowdown cams. During rotation of the cam shaft, the scavenge cams interact with the scavenge exhaust valves to open and close the scavenge exhaust valves when the scavenge exhaust valves are activated. Additionally, during rotation of the cam shaft, the blowdown cams interact with the blowdown exhaust valves to open and close the blowdown exhaust valves when the blowdown exhaust valves are activated, and at different times with respect to the opening and closing of the scavenge exhaust valves.