A cylinder head includes a hydraulic lash adjuster attachment portion provided with a hydraulic lash adjuster bore in which a hydraulic lash adjuster is inserted; a main oil provided at a position away from the hydraulic lash adjuster bore; a connection oil passage which connects the hydraulic lash adjuster bore and the main oil passage; and a side wall that defines a radially outer portion of the hydraulic lash adjuster bore. The side wall includes a first side wall portion and a second side wall portion that is positioned closer to an opening of the hydraulic lash adjuster bore than the first side wall portion is. A thickness of the second side wall portion is greater than a thickness of the first side wall portion.

A valvetrain assembly comprises a valve bridge, a capsule, a first rocker arm, and a second rocker arm. The valve bridge comprises an upper surface comprising a central pressure point and an offset pressure point and a lower surface comprising a lower pivot point, a first valve interface, and a second valve interface. The capsule can be connected to the lower pivot point, the capsule configured to provide to the pair of engine valves one or both of a lash adjusting function and a deactivating mode. The first rocker arm is configured to actuate against the central pressure point to transfer a first valve lift mode to the valve bridge. The second rocker arm is configured to actuate against the offset pressure point to transfer a second valve lift mode to the valve bridge.

In an internal combustion engine, a linkage is provided between an auxiliary motion source and a main motion load path, such that motions received by the linkage from the auxiliary motion source result in provision of a first force to at least one engine valve and a second force to the main motion load path in a direction toward a main motion source. Where an automatic lash adjuster is associated with the main motion load path, the second force may be selected to aid in the control of lash adjustments made by the automatic lash adjuster. In various embodiments, the linkage may be embodied in an mechanical linkage, whereas in other embodiments, an hydraulic linkage may be employed. The linkage may be incorporated into, or otherwise cooperate, a valve bridge or a rocker arm.

The present invention provides for Variable Valve Actuation comprising a cam, a valve suitable to displace between a closed position and an open condition caused by said cam, and further comprising a main rocker arm suitable to swing over a fulcrum, mechanically interacting with said valve, by means of a guide profile, and wherein said cam interacts with said main rocker arm causing said valve displacement as a consequence of said main rocker arm swinging. The target is to prevent a valve brake due to the guide profile and enable higher system stiffness. Accumulator less designs are feasible with this system.

A method of two-step variable valve lift (VVL) malfunction avoidance learning control may include: in a two-step VVL system which is operated with a main lift and a secondary lift, verifying, by an electronic control unit (ECU), an operation avoidance area based on locking of a lock pin of a cam follower ; performing VVL operation learning, in which a failure of occurrence of the second lift is determined on the basis of a locking failure of the cam follower due to an initially set value of the operation avoidance area; and reflecting the operation avoidance area to the two-step VVL system with a corrected set value which is obtained through the VVL operation learning.

The disclosure relates to a switching element comprising an external part and an internal part, which is axially displaceable in a bore of the external part. At least one radially displaceable locking element is disposed within at least one receptacle of the internal part and includes a flattened portion on a radially outwardly directed end. At least one recess of the external part can be acted upon by a control pressure and the at least one locking element can thereby be radially displaced from the locking position into a release position. At least in a respective locking position, a chamber delimited by the at least one locking element is spatially separated from the at least one recess of the external part by a respective locking section. At least one bypass is designed, which indirectly fluidly connects the at least one recess of the external part and a respective chamber.

A control method for a continuously variable valve lift mechanism includes: controlling a continuously variable valve lift mechanism to enter a limp mode when the continuously variable valve lift mechanism fails and disables an automatic valve lift changing function; driving and forcing the continuously variable valve lift mechanism to move to a maximum lift position; and triggering a self locking function to self lock the continuously variable valve lift mechanism at the maximum lift position when the continuously variable valve lift mechanism reaches the maximum lift position. A control system for a continuously variable valve lift mechanism, and a vehicle are also provided.

A type II valve train assembly that selectively opens first and second intake valves and first and second exhaust valves is provided. The valve train assembly includes an intake rocker arm assembly and an exhaust rocker arm assembly. The valve train assembly is configurable for operation in any combination of activated and deactivated states of engine braking and cylinder deactivation. The exhaust rocker arm assembly includes a first exhaust rocker arm, a second exhaust rocker arm and an engine brake exhaust rocker arm. A first exhaust HLA is associated with the first exhaust rocker arm. A second exhaust HLA is associated with the second exhaust valve. An exhaust actuation assembly selectively actuates to alter travel of the first and second exhaust HLA's to change a state of cylinder deactivation between activated and deactivated.

A valve train arrangement constructed in accordance to one example of the present teachings includes a rocker arm, a deactivating hydraulic lash adjuster (HLA) capsule, a lost motion spring (LMS) capsule and a lever. The rocker arm has a first end and a second end. The second end cooperates with a valve. The HLA capsule cooperates with the first end of the rocker arm. The LMS capsule has a lost motion spring. The LMS capsule is located in a position on the valve train arrangement that is offset from the HLA capsule. The lever is configured between the HLA capsule and the LMS capsule. During cylinder deactivation, load is transferred from the HLA capsule to the lever arm and ultimately to the lost motion spring in the LMS capsule.

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 to the outer arm at a first end of the inner arm and a first end of the outer arm, and a latch pin having a first position and a second position. The latch pin in the first position pivotally fixes the inner arm to the outer arm at a second end of each of the inner arm and a second end of the outer arm, and in the second position allows the inner arm and the outer arm to pivot independently. Two lost motion springs are respectively secured to mounts provided on the outer arm.