The present disclosure relates to a variable valve drive, in particular with a sliding cam system, for an internal combustion engine. The variable valve drive has a shaft and a cam carrier which is arranged rotationally conjointly and axially displaceably on the shaft and which has a first cam and a second cam. The variable valve drive has an actuator device for axially displacing the cam carrier, and has a carrying device which at least partially engages around a lever axle of a force transmission device and carries the actuator device. The variable valve drive can offer the advantage that an arrangement of the actuator device which is expedient in terms of structural space is made possible in the region of the lever axle. At the same time, support of the actuator device by means of the carrying device on the lever axle can stiffen the flexible lever axle by means of the engaging-around configuration.

A sleeve includes: a supply port communicated with a hydraulic oil supply source; a primary control port communicated with a retard chamber, a secondary control port communicated with an advance chamber; and a drain port communicated with an outside of a valve timing adjustment device. A spool includes: a pressure accumulation space formed at an inside of the spool; a supply passage configured to connect between the pressure accumulation space and the supply port; a primary control passage configured to connect between the pressure accumulation space and the primary control port; a secondary control passage configured to connect between the pressure accumulation space and the secondary control port; and a recycle passage configured to connect between the primary control port or the secondary control port and the pressure accumulation space. The recycle passage and the drain port are connected with each other at the inside of the sleeve.

A method of operating an internal combustion engine of a type that has a combustion chamber, a moveable valve having a seat formed in the combustion chamber, a camshaft on which a cam is mounted, and a rocker arm assembly having a rocker arm and a cam follower configured to engage the cam as the camshaft rotates. The method includes obtaining rocker arm position data, using the rocker arm position data to obtain camshaft position information, and using the camshaft position information in an engine management operation.

The present disclosure provides systems and methods to compensate for backlash within a cam phasing system. For example, compensating for backlash by commanding a predetermined amount of additional actuator movement to account for backlash within a cam phaser. According to some aspects, a spring is provided within a cam phaser to unidirectionally take up the backlash within the cam phasing system.

The present disclosure relates to a sliding cam system for an internal combustion engine. The sliding cam system has a camshaft and a plurality of cam carriers with in each case at least two cams, the plurality of cam carriers being arranged fixedly on the camshaft so as to rotate with it and in an axially displaceable manner. The sliding cam system has a plurality of fluid-actuated actuator apparatuses which are configured in each case for axially displacing a cam carrier of the plurality of cam carriers. The sliding cam system has a fluid feed apparatus which is provided for feeding a fluid in a fluidic connection upstream of the plurality of actuator apparatuses for actuating the plurality of actuator apparatuses. At least two actuator apparatuses of the plurality of actuator apparatuses are coupled fluidically for simultaneous actuation.

Methods and systems are provided for generating tumble in intake air by creating an asymmetrical annulus opening for flowing intake air into a combustion chamber of an engine cylinder. The asymmetrical annulus opening may be created by changing an angle of an intake valve disc of an intake valve. The angle of the intake valve disc may be varied based on engine operating parameters by extending or retracting one or more connect rods coupled to an annulus tumble guide movably housed inside an annulus channel.

The present disclosure provides a shift gate for a sliding cam system with at least two shifting grooves for engaging at least one actuator pin. The shifting grooves extend in a circumferential direction of the shift gate. The two shifting grooves are at least partially separated from one another in an entry region of the actuator pin. In a transition region adjacent to the entry region, they converge on each other in such a manner that they merge into each other and form a common groove. The shifting grooves each comprise at least one groove flank, in particular a lead flank and/or a runoff flank, which narrows the shifting grooves at least in the transition region, in such a manner that a groove width of the shifting grooves in the transition region is smaller than a groove width of the shifting grooves in the entry region of the actuator pin.

A modularized multifunctional variable valve actuation system for use in a six-cylinder internal combustion engine. The system includes two fuel supply modules that cooperate with two two-way two-position valves for implementing a continuously variable valve event, and that cooperate with two three-way two-position valves and one two-way two-position valve for implementing a fully variable valve event.

The invention relates to an improved system of electro-mechanical hydraulic valve lifters for piston engine automobiles that increases fuel economy and reduces fuel emissions. The electro-mechanical hydraulic valve lifters enclose a magnetorheological fluid chamber, containing magnetorheological fluid. A control module manages voltage sent to the magnetorheological fluid in the magnetorheological fluid chamber. The control module introduces various amounts of magnetic flux to the magnetorheological fluid in the magnetorheological fluid chamber. The magnetorheological fluid's viscosity changes based on the amount of magnetic flux applied to it from the electromagnets and, along with the magnetorheological fluid chamber spring, controls how much an intake and exhaust port of the spark plug engine opens to control the amount of fuel used and exhaust let out of the engine.

A valvetrain suitable for an internal combustion engine of a type that includes a combustion chamber, a moveable valve having a seat formed within the combustion chamber, and a camshaft. The valvetrain includes a rocker arm assembly having a rocker arm and an electrical device that either configures the rocker arm assembly or provides position feedback for a part of the rocker arm assembly. The valvetrain includes a framework that fits around a spark plug tube while holding a component of a circuit that includes the electrical device in a position adjacent the rocker arm assembly. The position may place the component in contact with or very close to the rocker arm assembly. This framework structure may effectively utilize the available space under a valve cover while facilitating correct positioning of the component in relation to the rocker arm assembly.