A combined exhaust and engine brake rocker arm assembly configured to selectively open first and second exhaust valves, includes a rocker arm body, an exhaust rocker arm assembly formed in the rocker arm body, and an engine brake rocker arm assembly formed in the rocker arm body and configured to operate in a collapse mode and a rigid mode. The exhaust rocker arm assembly is configured to selectively engage a valve bridge to open the first and second exhaust valves, and the engine brake rocker arm assembly is configured to selectively engage the valve bridge to open only the first exhaust valve.

A method for controlling vehicle speed comprises selecting an engine speed profile for a vehicle. Road grade data is received and processed to determine a road grade for the vehicle. Vehicle speed data is received and processed to determine a vehicle speed for the vehicle. A cylinder deactivation mode for a valvetrain of a multi-cylinder engine of the vehicle is selected. The cylinder deactivation mode comprises deactivating one or more intake valve, exhaust valve, and fuel injection for one or more cylinder of the multi-cylinder engine. The selected cylinder deactivation mode provides a controlled deviation from the selected engine speed profile at the road grade and vehicle speed.

A latch assembly comprises a latch pin configured to reciprocate in a latch bore. The latch pin comprises a main body comprising a first plug end, a second plug end, and a clearance between the first plug end and the second plug end. The latch pin is configured to selectively move in the latch bore. A rocker arm assembly can comprise the latch assembly. An outer arm can be configured to rotate about a rocker shaft and comprise the latch bore. An inner arm can at least be partially disposed within the outer arm and configured to rotate. When the latch pin is in the activated position, the inner arm is configured to transfer force to the outer arm via the latch pin. When the latch pin is in the deactivated position, the inner arm is configured to move in the clearance and in the lost motion gap.

An overhead cam engine system comprises a rotating overhead exhaust cam rail comprising a plurality of exhaust lobes. A first switching roller finger follower actuates a first exhaust valve, and is configured to switch between a first lift profile and a second lift profile. A second switching roller finger follower is coupled to actuate a second exhaust valve, and is configured to switch between a third lift profile and a fourth lift profile. The third and fourth lift profile are different than the first and second lift profile. An actuation assembly is connected to switch the first switching roller finger follower and the second switching roller finger follower to select between at least three exhaust lift modes to open and close the first exhaust valve and the second exhaust valve using combinations of the first, second, third and fourth lift profiles.

An exhaust valve rocker arm assembly includes an exhaust rocker arm and a valve bridge operably associated with the rocker arm. The valve bridge includes a main body and a lever rotatably coupled to the main body. The main body is configured to engage the first exhaust valve, and the lever is configured to engage the second exhaust valve.

The present invention is capable of more smoothly changing a phase of a cam shaft in a rotation direction. A variable valve mechanism changes an opening/closing timing of an intake valve or an exhaust valve in response to an engine rotation speed. The variable valve mechanism includes: a cam sprocket which rotates in response to a rotation of a crank shaft; an intake cam shaft which is integrated with an intake cam and is provided to be rotatable relatively to the cam sprocket; and a link member that transmits a rotation from the cam sprocket to the intake cam shaft. The link member is supported by the cam sprocket to be swingable and swings in response to a change in rotation speed of the cam sprocket to rotate the intake cam shaft relatively to the cam sprocket.

The present invention can achieve a variable valve mechanism having a simple and compact configuration. A variable valve mechanism changes an opening/closing timing of an intake valve or an exhaust valve in response to an engine rotation speed. The variable valve mechanism includes: a cam sprocket which rotates in response to a rotation of a crank shaft; an intake cam shaft which is integrated with an intake cam; an exhaust cam shaft which is integrated with an exhaust cam; and a governor flange that transmits a rotation of the cam sprocket to the intake cam shaft and the exhaust cam shaft. The intake cam shaft and the exhaust cam shaft are formed so that the other cam shaft is inserted through one cam shaft to be relatively rotatable. The governor flange is provided to rotate along with the intake cam shaft and rotates relative to the cam sprocket under a predetermined condition.

A rocker arm assembly can include an outer arm having an outer rocker shaft bore configured to receive a rocker shaft and an inner arm having an inner rocker shaft bore configured to receive the rocker shaft. The inner arm can be configured to selectively rotate. A latch pin can be movably seated in the outer arm and configured to move between a latched position and an unlatched position. The rocker arm assembly can further include a lost motion spring. The lost motion spring can include a first end connected to a connecting portion of the inner arm above the inner rocker shaft bore and a second end connected to the outer arm. The inner arm can include an inner arm stop member configured contact with a corresponding outer arm stop member of the outer arm.

A rocker arm assembly can comprise a cam side rocker arm portion configured to selectively rotate about a pivot location. The cam side rocker arm portion can comprise a first socket above the pivot location, and a cam end configured to receive a lift profile from a cam lobe. A valve side rocker arm portion can be configured to rotate about the pivot location relative to the cam side rocker arm portion. The valve side rocker arm portion can comprise a second socket above the pivot location. A lost motion spring can span between the first socket and the second socket.

A switching roller finger follower (SRFF) assembly for valve actuation includes an outer arm and an inner arm pivotally coupled to the outer arm via a pivot axle and at least partially disposed within the outer arm. The inner arm is unitarily formed and has a first inner side arm and a second inner side arm having respective laterally spaced apart longitudinal bends that each define pin apertures. A spring engagement pin extends through the pin apertures, a pair of lost motion springs are supported by the pivot axle, an inner roller is rotatably coupled to the inner arm, and a pair of outer rollers are disposed on respective axles supported by the outer arm.