There is provided a variable valve apparatus including: a plurality of rocker arms; a coupling pin disposed in a housing hole of the rocker arm closer to one side; a release pin disposed in a housing hole of the rocker arm closer to the other side; a pressing member; a transmission member; and a push-back member disposed so as to push back the transmission member from the other side. The pressing member is configured to push the coupling pin into the housing hole of the rocker arm closer to the other side to couple the plurality of rocker arms. The transmission member is configured to push back the coupling pin into the housing hole of the rocker arm closer to the one side to release a coupling of the plurality of rocker arms.

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 rocker arm includes an outer arm having a first side and a second side, an inner arm positioned between the first side and the second side of the outer arm, a pivot axle pivotally coupling the inner arm and the outer arm at a first end of each of the inner arm and the outer arm, and a latch having a first position and a second position. The latch in the first position pivotally fixes the inner arm and the outer arm at a second end of each of the inner arm and the outer arm, and in the second position allows the inner arm and the outer arm to pivot independently. The latch is responsive to hydraulic pressure in a hydraulic fluid passage to selectively move to other of the first position and the second position. A lost motion spring is coupled to the inner arm.

A sensor mounting structure for an engine is provided. The sensor mounting structure offers a greater flexibility in mounting a sensor which detects an operation of an actuation member disposed at an inner wall spaced apart from an outer wall of a cylinder head of a valve gear. A sensor mounting structure for an engine includes a valve gear provided at a cylinder head and a sensor detecting an operation of the valve gear. The sensor is mounted on a sensor mounting hole formed at a head inner wall of the cylinder head covered with a cylinder head cover.

A system includes a rocker arm assembly for operative engagement with a first and second cam. The assembly includes a first arm for operatively engaging the first cam for a first desired lift profile, a second arm for operatively engaging the second cam for a second desired lift profile, where the second arm includes a latch to engage the second arm with the first arm. The latch is responsive to supplied oil pressure and release oil pressure to switch between lift profiles. The system includes the latch coupled to the supplied or released oil pressure to engage the arms before the first and second arms are engaged with the base circle portion of each of the respective first and second cams.

A method of operating an internal combustion engine that includes a valvetrain having a rocker arm assembly including a rocker arm on which a latch pin is mounted. An actuator for the latch pin, including an electromagnet, is mounted separately from the rocker arm. Rocker arm position information is obtained by gathering and analyzing data relating to a current or voltage in an electrical circuit that is operative to power the electromagnet. The rocker arm position information is used to perform a diagnostic.

A magnetic sensor arrangement for determining a position of an actuator may include a magnetic sensor to determine the position of the actuator, where the actuator may be configured to reciprocate along a longitudinal axis of an actuator housing of the actuator, such that at least a portion of the actuator may cross an end plane of the actuator housing when reciprocating along the longitudinal axis, and the magnetic sensor may sense a set of components of a magnetic field generated by a magnet, and determine, based on the sensed set of components of the magnetic field, a position of the actuator along the longitudinal axis of the actuator housing of the actuator, where the magnet may be connected to or forms part of the actuator, and where the magnetic sensor may be connected to the actuator housing, and where a portion of the magnetic sensor may be positioned at least in a first actuator position beyond the end plane of the actuator housing.

A system includes a rocker arm assembly for operative engagement with a first and second cam. The assembly includes a first arm for operatively engaging the first cam for a first desired lift profile, a second arm for operatively engaging the second cam for a second desired lift profile, where the second arm includes a latch to engage the second arm with the first arm. The latch is responsive to supplied oil pressure and release oil pressure to switch between lift profiles. The system includes the latch coupled to the supplied or released oil pressure to engage the arms before the first and second arms are engaged with the base circle portion of each of the respective first and second cams.

A novel cylinder head arrangement for an in-line four cylinder or eight cylinder engine. A modified arrangement allows additional space for installation of wider rocker arm assemblies used for variable valve lift (VVL), cylinder deactivation (CDA) and other types of variable valve actuation (VVA). In one embodiment, cam towers adjacent the end two cylinders are not used. At least one end support is used, which may be an outboard bearing on a camshaft for each end. The wider rocker assemblies may then be installed. In another embodiment, cam towers adjacent the inner two cylinders are eliminated and a single camshaft support piece with a support bearing is installed between the inner cylinders to provide support for the camshafts. The wider rocker assemblies may then be installed on at least one of the middle cylinders. A novel oil control valve operates latches in switching rocker arm assemblies.

A modified rocker assembly having an offset end is designed for engine heads having an obstruction preventing use of a symmetric switching rocker arm. The modified rocker assembly has an obstructed side and a non-obstructed side and has an outer structure with a first end, and an inner rocker structure fitting within the outer structure, the inner structure also having a first end. The modified rocker assembly has an axle pivotally connecting the first ends of inner structure to the outer structure, such that the inner structure pivots within the outer structure around the axle. At least one torsion spring on one side of the axle rotationally biases the inner structure relative to the outer structure. The outer structure is offset on the obstructed side as it extends from the second end toward the first end, creating the first offset portion to provide additional clearance on the obstructed side.