The invention relates to an internal combustion engine gas exchange valve actuator and is used to displace one or more internal combustion engine valves thereby improving the operation and extending the capabilities of the engine. The actuator includes a casing (2) attached to the engine head (1) and with a hollow cylinder (3) formed inside it and containing a reciprocating piston (6) with a piston rod. Provision is made in the casing (2) which is closed by a cap (4), for a loop for controlled charging and discharging of the pressurized fluid and for a solenoid valve with direct electromagnetic control. The solenoid valve is positioned above the piston (6) and is formed as a plunger (19) having a lower cylindrical widening with axial orifices (20) and an upper part with a central recess (22) and radial orifices (23) and (24).

A variable cam timing phaser of a variable cam timing system includes a housing and a rotor moveable with respect to the housing. The rotor and the housing define advance and retard chambers. The variable cam timing phaser also includes a control valve assembly. The control valve assembly includes a valve housing defining a valve housing interior, a supply port, first and second working ports, and an exhaust port. The control valve assembly also includes a piston moveable for controlling flow of the hydraulic fluid through the valve housing interior. The exhaust port is fluidly connectable with a sump through a vent path that is defined by at least one of the valve housing and the rotor. The vent path is configured to prevent air from being sucked into the variable cam timing phaser through the vent path.

The disclosure relates to a vane type camshaft adjuster for a motor vehicle drive train. The camshaft adjuster having a stator, a rotor arranged such that it can rotate relative to the stator, working chambers formed between the stator and the rotor, each working chamber being divided into two sub-chambers by a radially projecting blade of the rotor, and a reservoir connected to the sub-chambers for storing hydraulic medium. The sub-chambers can be connected to a pump or a tank according to a switch position of a control valve of the camshaft adjuster. The control valve has a switch position in which a first sub-chamber of the two sub-chambers is connected to the tank and a second sub-chamber of the two sub-chambers is blocked from the pump.

Methods and systems are provided for a valve system for actuating two cylinder valves in an engine. In one example, the valve system may include a single pump and a solenoid valve capable of non-concurrently actuating the two cylinder valves coupled to separate cylinders.

The present invention provides for Variable Valve Actuation comprising a cam, a valve suitable to displace between a closed position and an open condition caused by said cam, and further comprising a main rocker arm suitable to swing over a fulcrum, mechanically interacting with said valve, by means of a guide profile, and wherein said cam interacts with said main rocker arm causing said valve displacement as a consequence of said main rocker arm swinging. The target is to prevent a valve brake due to the guide profile and enable higher system stiffness. Accumulator less designs are feasible with this system.

A camshaft adjuster (1) is provided, including a drive element (2) and a driven element (3), which can be rotated in relation to the drive element within an angular range and can be connected to a camshaft, wherein pressurizable working chambers (4) for rotating the drive element (2) with respect to the driven element (3) are formed between the drive element (2) and the driven element (3), wherein the camshaft adjuster (1) has a volume accumulator (5) for collecting hydraulic medium, wherein the volume accumulator (5) supplies the hydraulic medium to a vacuum-pressurized working chamber (4) via a check valve (6) in that the vacuum in the working chamber (4) opens the check valve (6), characterized in that the check valve (6) is arranged in an axial position between the working chamber (4) and the volume accumulator (5), and the volume accumulator (5) is formed by a cover element (7) connected to the drive element (2) for conjoint rotation.

A hydraulic camshaft adjuster for adjusting the control times of gas exchange valves of an engine is provided. A stator is rotatable synchronously with a crankshaft of the engine. A rotor is arranged so as to be rotatable relative to the stator, and is rotatable synchronously with a camshaft. A plurality of ribs are provided on the stator, dividing an annular chamber between the stator and the rotor into a plurality of pressure chambers. A rotor hub and a plurality of blades extend radially outward from the rotor hub, dividing the pressure chambers into two working chambers having different effective directions. An additional connectable pressure booster is provided at least in an effective direction of the hydraulic camshaft adjuster. The pressure booster can boost the rotor when active.

The disclosure relates 10 a device which is used to adjust the valve stroke of internal combustion engines and has an actuation element for the valve stem. The actuation element is actuated by the camshaft and has a receiving space for a pressure medium. The receiving space is fluidically connected to a reservoir space of an adjustment reservoir. The volume of the reservoir space can be adjusted by means of a reservoir piston. The reservoir piston is loaded toward the reservoir space with a force that is greater than the force applied by the pressure medium and that is less than the restoring force acting on the piston.

A valve train for the variable actuation of an inlet valve and an outlet valve of a combustion chamber of an internal combustion engine, having a first operative connection between a valve actuating device and the inlet valve and a second operative connection between the valve actuating device and the outlet valve. The first operative connection and the second operative connection are assigned an interrupting element which is set up to temporarily interrupt the operative connections. The first operative connection and the second operative connection are connected to the same interrupting element in such a way that the first operative connection and the second operative connection can be interrupted temporarily by way of the interrupting element.

Apparatus (10) for a hydraulic valvetrain system (90) comprising: a first oil retaining means 5 (12), a second oil retaining means (20) and an oil conveyance means (14, 16) having a first end (18) operably connected to the first oil retaining means (12) and a second end (22) operably connected to the second oil retaining means (20). The second oil retaining means (20) is configured to receive oil from the first oil retaining means (12) via the oil conveyance means (14, 16), the first oil retaining means (12) is configured to receive oil from the oil 10 conveyance means (14, 16) and the oil conveyance means (14, 16) is configured to receive oil from the second oil retaining means (20).