A spring arrangement for a variable valve drive of an internal combustion engine includes an intermediate lever, a control shaft, a control shaft roller, a working cam contour, and a spring element. The intermediate lever comprises a contact surface, a camshaft roller which bears against a camshaft, and a slot roller which bears against a slotted guide. The control shaft roller is arranged on the intermediate lever to face away from the slotted guide. The control shaft roller bears against the control shaft. The working cam contour is formed at an end of the intermediate lever opposite the camshaft roller. The spring element comprises a force component on the contact surface in the direction of the camshaft and the slotted guide, and an end leg. The spring element loads the camshaft roller against the camshaft and the slot roller against the slotted guide. The end leg bears against the contact surface.

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.

The cam follower roller device comprises a body, a shaft mounted on the body, a roller mounted on the shaft and able to rotate, and a plain bearing interposed radially between the shaft and the roller. An outer surface and/or an inner surface of the plain bearing comprise a plurality of cavities. The ratio of the sum of the surfaces areas of the cavities to the total surface area of the outer surface, or of the inner surface, in which the cavities are formed is between 2% and 40%. The cavities have a depth between 0.5 μm and 5 μm.

A valve operating apparatus for use in an internal combustion engine includes an intake cam 38, an intake rocker arm 33 rotatable about a rotational shaft 35 and driven by the intake cam 38, and an intake valve 40 pushed by a pusher 70 of the intake rocker arm 33, the internal combustion engine has a cylinder assembly 12L lying horizontally, and the intake rocker arm 33 has a weight 67 adjusting the center of gravity of the rocker arm 33 to position the pusher 70 above the rotational shaft 35 while the intake cam 38 is held out of abutting contact with the intake rocker arm 33.

A mechanical system that forms one of a cam follower or a rocker arm. The mechanical system comprises a support element including a first body portion and a second body portion, a pin extending between two opposite ends along a first axis and supported by the first body portion of the support element, and a roller mounted on pin, movable in rotation relative to the pin around the first axis and adapted to roll on a cam. The mechanical system further comprises a spacing element comprising a first body portion connected to the second body part of the support element and a second body portion adapted to be supported by a movable support.

A mechanical system that forms one of a cam follower or a rocker arm. The mechanical system comprises a support element including a first body portion and a second body portion, a pin extending between two opposite ends along a first axis and supported by the first body portion of the support element, and a roller mounted on pin, movable in rotation relative to the pin around the first axis and adapted to roll on a cam. The mechanical system further comprises a spacing element comprising a first body portion connected to the second body part of the support element and a second body portion adapted to be supported by a movable support.

The invention relates to a locking device for a switchable valve drive component, including a first locking body and a second locking body which can be brought into engagement with one another or out of engagement in order to couple to one another or to uncouple two component parts arranged movably with respect to one another, wherein at least one of the two locking bodies has at least one curved surface. In order to increase the wear resistance of the locking device, provision is made for at least one of the two locking bodies to have a plurality of curved surfaces of which the respective curvature is described by radii of identical length having constructional center points spaced apart from one another.

An engine that can implement cylinder deactivation (CDA) includes: a plurality of cylinders; a variable valve duration apparatus that is mounted in at least one of the plurality of cylinders and that performs a long duration mode and a short duration mode of an intake valve of a corresponding cylinder; a CDA apparatus that is mounted in at least another one of the plurality of cylinders and that performs a general operation mode and a CDA mode of an intake valve and an exhaust valve of a corresponding cylinder; and a controller that controls operation of the variable valve duration apparatus and the CDA apparatus according to an operation state of an engine, wherein the controller controls the variable valve duration apparatus to operate in a short duration mode, when the CDA apparatus operates in the CDA mode.

A mechanical system, comprising a support element, a pin extending along a first axis and comprising two opposite ends, each adapted to be fitted in the support element for radial retention of the pin relative to the first axis, and a roller element movable in rotation relative to the pin around the first axis. The mechanical system includes two ribs resting on either side of the ends for axial retention of the pin along the first axis. The mechanical system can be integrated into either an injection pump or a valve actuator.