A novel latch seat for a switching rocker arm assembly used in variable valve actuation (VVA) systems for internal combustion engines. The seat is formed interactively in the assembled switching rocker arm using a novel fixture and press. The press interactively creates a curved dimple of the correct curvature, position and depth while measuring several lash dimensions. Since the latch seat is formed on the assembled rocker arm assembly, the latch seat depth is designed to account for the inaccuracies in the rocker arm assembly parts which create lash. Therefore all of the parts may be made with less precision since the latch seat is sized to compensate for the inaccuracies of all of the parts. The rocker arm assembly parts now may be manufactured to less stringent standards, but result in a rocker arm assembly with same accuracy of rocker arm assemblies manufactured to previous standards.

A variable valve driving mechanism of an engine includes a rocker arm configured to control open and close of a valve and a servo rocker arm arranged in parallel to the rocker arm. A swing end of the servo rocker arm extends to the top of the swing end of the rocker arm. A valve adjustment gap provided in the swing direction of the servo rocker arm and the rocker arm is formed between the servo rocker arm and the rocker arm. A gap compensating device telescopically filling the valve adjustment gap and configured to adjust the valve to be delayed to close or open in advance when extending to the valve adjustment gap is provided between the servo rocker arm and the rocker arm.

A variable valve driving mechanism of an engine includes a rocker arm configured to control open and close of a valve and a servo rocker arm arranged in parallel to the rocker arm. A swing end of the servo rocker arm extends to the top of the swing end of the rocker arm. A valve adjustment gap provided in the swing direction of the servo rocker arm and the rocker arm is formed between the servo rocker arm and the rocker arm. A gap compensating device telescopically filling the valve adjustment gap and configured to adjust the valve to be delayed to close or open in advance when extending to the valve adjustment gap is provided between the servo rocker arm and the rocker arm.

A switching rocker arm assembly can include an outer arm having a first outer side arm and a second outer side arm, each of the first and second outer side arms having a high lift lobe contacting surface, and an inner arm disposed between the first and second outer side arms and pivotably secured to the outer arm, the inner arm having a low lift lobe contacting surface and defining a latch bore. A latch assembly can be arranged at least partially within the latch bore of the inner arm. The latch assembly can include a latch pin having an orientation pin receiving recess, a sleeve engaging the latch pin and having an orientation pin opening, and an orientation pin extending through the orientation pin opening into the orientation pin receiving recess. The orientation pin can have a substantially cylindrical first wall and a substantially cylindrical second wall.

A switching rocker arm assembly can include an outer arm having a first outer side arm and a second outer side arm, each of the first and second outer side arms having a high lift lobe contacting surface, and an inner arm disposed between the first and second outer side arms and pivotably secured to the outer arm, the inner arm having a low lift lobe contacting surface and defining a latch bore. A latch assembly can be arranged at least partially within the latch bore of the inner arm. The latch assembly can include a latch pin having an orientation pin receiving recess, a sleeve engaging the latch pin and having an orientation pin opening, and an orientation pin extending through the orientation pin opening into the orientation pin receiving recess. The orientation pin can have a substantially cylindrical first wall and a substantially cylindrical second wall.

A continuous variable valve duration apparatus includes a camshaft, a first and second cam portion, each including a cam and a cam key, where the camshaft is inserted into the first and second cam portions and where relative phase angles with respect to the camshaft are variable, a first and second inner bracket transmitting a rotation of the camshaft to the first and second cam portions respectively, a first and second slider housing, a cam cap rotatably supporting the first and second cam portions respectively, a slider pin rotatably inserted into the first sliding hole and slidably inserted into the camshaft, a cam pin on which a cam key slot for the cam key to be slidably inserted thereinto is formed, a control shaft disposed parallel to the camshaft and engaged with the first and second slider housings, and a control portion selectively rotating the control shaft.

A continuous variable valve duration apparatus includes a camshaft, a first and second cam portion, each including a cam and a cam key, where the camshaft is inserted into the first and second cam portions and where relative phase angles with respect to the camshaft are variable, a first and second inner bracket transmitting a rotation of the camshaft to the first and second cam portions respectively, a first and second slider housing, a cam cap rotatably supporting the first and second cam portions respectively, a slider pin rotatably inserted into the first sliding hole and slidably inserted into the camshaft, a cam pin on which a cam key slot for the cam key to be slidably inserted thereinto is formed, a control shaft disposed parallel to the camshaft and engaged with the first and second slider housings, and a control portion selectively rotating the control shaft.

A method and apparatus for continually and rapidly adjusting the output torque of an engine according to a torque demand uses an active tappet to vary the instant air charge in a combustion chamber, so as to modulate engine torque during an automatic change of speed ratio. The invention allows substantially efficient combustion throughout the engine operating map. Various methods of changing the charge of air are disclosed.

A method and apparatus for continually and rapidly adjusting the output torque of an engine according to a torque demand uses an active tappet to vary the instant air charge in a combustion chamber, so as to modulate engine torque during an automatic change of speed ratio. The invention allows substantially efficient combustion throughout the engine operating map. Various methods of changing the charge of air are disclosed.

A valve train for an internal combustion engine may include a camshaft and a cam follower. The valve train may also include two first cams arranged on the camshaft in a torque-proof manner and at an axial distance from one another. Each of the two first cams may include an identical first cam contour. The valve train may also include two second cams arranged on the camshaft in a torque-proof manner and at an axial distance from one another. Each of the two second cams may also include an identical second cam contour. The two first cams and the two second cams may alternate in an axial direction on the camshaft. The cam follower may be axially adjustable between a first and second position, and may be drivingly connected to the two first cams in the first position and drivingly connected to the two second cams in the second position.