A variable valve mechanism of an internal combustion engine includes an outer arm, an inner arm, a switching device that switches between a coupled state and a non-coupled state, and a lost motion spring. The lost motion spring has an extending portion extending from the outside of the space to the inside of the space. The extending portion has a contact portion that is in contact with the inner arm in the space and being configured to swing in conjunction with swinging of the inner arm. A through-hole is formed in a vertically intermediate portion of the outer arm such that connecting portions are provided at vertically opposite sides of the through-hole, and a portion of the extending portion, a swinging amount of which is smaller than that of the contact portion, passes through the through-hole that allows the portion to swing therein.

A variable valve mechanism of an internal combustion engine includes an outer arm, an inner arm, a switching device that switches between a coupled state and a non-coupled state, and a lost motion spring. The lost motion spring has an extending portion extending from the outside of the space to the inside of the space. The extending portion has a contact portion that is in contact with the inner arm in the space and being configured to swing in conjunction with swinging of the inner arm. A through-hole is formed in a vertically intermediate portion of the outer arm such that connecting portions are provided at vertically opposite sides of the through-hole, and a portion of the extending portion, a swinging amount of which is smaller than that of the contact portion, passes through the through-hole that allows the portion to swing therein.

A method for adjusting a valve lash in an internal combustion engine includes receiving a first signal generated by a sensor secured to the internal combustion engine, the first signal being indicative of a closing of a valve, receiving a second signal indicative of at least one of an engine speed of the internal combustion engine or a position of a camshaft of the internal combustion engine, and automatically determining an adjusted amount of lash associated with the valve based on the received first signal and the received second signal. The method also includes comparing the adjusted amount of lash to at least one predetermined threshold, and providing, in response to determining that the adjusted amount of lash is greater than the at least one predetermined threshold, a valve lash re-adjustment notification.

A method for adjusting a valve lash in an internal combustion engine includes receiving a first signal generated by a sensor secured to the internal combustion engine, the first signal being indicative of a closing of a valve, receiving a second signal indicative of at least one of an engine speed of the internal combustion engine or a position of a camshaft of the internal combustion engine, and automatically determining an adjusted amount of lash associated with the valve based on the received first signal and the received second signal. The method also includes comparing the adjusted amount of lash to at least one predetermined threshold, and providing, in response to determining that the adjusted amount of lash is greater than the at least one predetermined threshold, a valve lash re-adjustment notification.

A castellation device comprises a shaft surrounded by three castellation members. A first castellation member is rotatably mounted on the shaft and comprises a first end and a second end opposite to the first end. A second castellation member is slidably mounted along the shaft adjacent the first end of the first castellation member. A third castellation member is mounted to the shaft adjacent the second end of the first castellation member. A bias spring is disposed between the second castellation member and the third castellation member and is configured to bias the second castellation member away from the third castellation member. Optionally, an annular shroud can enclose the three castellation members. The first castellation member is rotatable relative to the second and third castellation members between a first position and a second position.

A method of operating an internal combustion engine having an electrical circuit that includes a connection closed by abutment between two distinct parts, one of which is mounted to a rocker arm of a rocker arm assembly and another that is mounted to a part distinct from the rocker arm. The connection is structured such that the movement of the rocker arm causes relative motion between the surfaces of the distinct parts that close the connection. The relative motion causes the circuit resistance to transition between values within a first range and values within a second range. The transitions of resistance between those ranges are detected and their presence, absence, or timing used for purposes of providing diagnostic feedback or control.

A method of operating an internal combustion engine having an electrical circuit that includes a connection closed by abutment between two distinct parts, one of which is mounted to a rocker arm of a rocker arm assembly and another that is mounted to a part distinct from the rocker arm. The connection is structured such that the movement of the rocker arm causes relative motion between the surfaces of the distinct parts that close the connection. The relative motion causes the circuit resistance to transition between values within a first range and values within a second range. The transitions of resistance between those ranges are detected and their presence, absence, or timing used for purposes of providing diagnostic feedback or control.

A preassembled module for a variable-lift valve drive of an internal combustion engine is provided for installation into a cylinder head. The module has a base plate with an electric linear actuator which lies on an upper side of the base plate. A guide plate, which lies on the upper side, has an outer side wall arranged to guide a slide piece. The guide piece extends below the base plate two downwardly pointing actuating fingers. Each respective actuating finger has a contact surface for moving a transverse coupling slide of a switchable rocker arm. The slide piece has a bracket which protrudes over the guide plate with a contact landing arm which runs transversely relative to the electric linear actuator. An actuator-side end of the contact landing arm is in contact with an actuating pin of the electric linear actuator to move the slide piece.

A preassembled module for a variable-lift valve drive of an internal combustion engine is provided for installation into a cylinder head. The module has a base plate with an electric linear actuator which lies on an upper side of the base plate. A guide plate, which lies on the upper side, has an outer side wall arranged to guide a slide piece. The guide piece extends below the base plate two downwardly pointing actuating fingers. Each respective actuating finger has a contact surface for moving a transverse coupling slide of a switchable rocker arm. The slide piece has a bracket which protrudes over the guide plate with a contact landing arm which runs transversely relative to the electric linear actuator. An actuator-side end of the contact landing arm is in contact with an actuating pin of the electric linear actuator to move the slide piece.

A rocker assembly for a type III center pivot valvetrain comprises a rocker arm having a cam end, a center pivot bore, and a valve end which includes a first actuator bore and a second actuator bore. The rocker assembly further comprises a a cylinder deactivation actuator arranged in the first actuator bore. The cylinder deactivation actuator comprises a hydraulically actuated latch assembly configured to selectively switch between a latched configuration and an unlatched configuration and a a mechanical lash-setting sleeve distanced from a travel stop defined within the first actuator bore. The cylinder deactivation actuator further comprises a lash step disposed below the mechanical lash-setting sleeve and extending into the first actuator bore. The hydraulically actuated latch assembly is configured to selectively travel between the travel stop and the lash step when the hydraulically actuated latch assembly is in the latched configuration.