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).

The valve opening/closing timing control device includes: the driving rotating body; the driven rotating body; an advancing chamber and a retarding chamber formed by partitioning a fluid pressure chamber between the driving and driven rotating bodies; and a phase control unit supplying pressurized fluid to the advancing or retarding chamber via an advancing channel or a retarding channel penetrating through the driven rotating body. In the driven rotating body, an outer circumferential member and an inner circumferential member are formed integrally/coaxially with each other. The advancing and retarding channel form a predetermined angle. Between every pair of an advancing channel and a retarding channel, a groove portion is formed in one of an inner circumferential surface of the outer circumferential member and an outer circumferential surface of the inner circumferential member, and an elongated protruding portion is formed on the other, at a position that corresponds to the groove portion.

The object of this invention is to simplify the timing system of all types of internal combustion engine. The system eliminates existing conventional timing trains. The hydraulic, mechanical or electrical/electronic direct timing systems that form the subject of the invention offer minimal resistance and minimal transmission. The piston strokes are given directly by the crankshaft by means of a system fixed thereto which via a mechanical or hydraulic or electrical or electronic system transmits the strokes to the cylinder valves. The system can be connected to all types of indirect transmission and has adjusting systems that allow it to be adapted to suit all types of internal combustion engine.

A system that provides adjustable actuation timing of one or more valve(s) (16) in a piston engine includes a position sensor (12) and a variable valve actuation assembly (10). The valve(s) (16) can be intake and/or exhaust valves in an internal combustion engine of an automobile. The position sensor (12) takes position readings of the valve(s) (16) as the valve(s) (16) actuate in the piston engine. The variable valve actuation assembly (10) controls actuation timing of the valve(s) (16). Actuation timing of the valve(s) (16) is adjustable based, in part or more, upon one or more position reading(s) of the position sensor (12). The variable valve actuation assembly (10) can be a lost motion assembly (10).

A valve gear for an engine includes cam shafts, first and second support walls, and rocker arms supported on the first and second support walls by supports. The supports switch among a plurality of support modes. The supports include first and second shaft holes, rocker shafts, tracks in the support walls, and return springs. The rocker shafts, move to positions where the support walls and the rocker arms are connected via the rocker shafts in a first support mode. In a second support mode, the rocker shafts move to positions where the connection between the support walls and the rocker arms is canceled. This makes it possible to provide a valve gear for an engine capable of smoothly switching a normal operation state support mode and cylinder resting state support mode, thus increasing the reliability of the operation.

A hydraulics unit for an internal combustion engine with a hydraulically variable gas exchange valve gear, is provided that includes a hydraulic housing having a pressure chamber, a pressure relief chamber and a venting duct. The venting duct is connected, on a hydraulic housing inner side, to the pressure relief chamber via a restriction and opens on a hydraulic housing outer side. The venting duct has a siphon with a downward first duct section and an upward second duct section, respectively in the direction of gravity and in the venting direction. When a gas exchange valve is closed, a lowermost section of the siphon is below a boundary of a pressure chamber defined by a slave piston.

A hydraulics unit for an internal combustion engine with a hydraulically variable gas exchange valve gear, is provided that includes a hydraulic housing having a pressure chamber, a pressure relief chamber and a venting duct. The venting duct is connected, on a hydraulic housing inner side, to the pressure relief chamber via a restriction and opens on a hydraulic housing outer side. The venting duct has a siphon with a downward first duct section and an upward second duct section, respectively in the direction of gravity and in the venting direction. When a gas exchange valve is closed, a lowermost section of the siphon is below a boundary of a pressure chamber defined by a slave piston.

Methods and systems are provided for providing compression release during a stop/start event in an engine. In one example, a method includes: responsive to a request for a stop/start event in an engine with a continuously variable valve lift (CVVL) system including a compression release hydraulic valve actuator coupled to a valve of a first cylinder, determining a desired stop position of the engine; and prior to restarting the engine during the stop/start event, adjusting the compression release hydraulic valve actuator to open the valve during a compression stroke of the first cylinder. In this way, an amount of torque used to restart the engine may be reduced.

Methods and systems are provided for providing compression release during a stop/start event in an engine. In one example, a method includes: responsive to a request for a stop/start event in an engine with a continuously variable valve lift (CVVL) system including a compression release hydraulic valve actuator coupled to a valve of a first cylinder, determining a desired stop position of the engine; and prior to restarting the engine during the stop/start event, adjusting the compression release hydraulic valve actuator to open the valve during a compression stroke of the first cylinder. In this way, an amount of torque used to restart the engine may be reduced.

A hydraulics unit for an internal combustion engine with a hydraulically variable gas exchange valve gear, is provided that includes a hydraulic housing having a pressure chamber, a pressure relief chamber and a venting duct. The venting duct is connected, on a hydraulic housing inner side, to the pressure relief chamber via a restriction and opens on a hydraulic housing outer side. The venting duct has a siphon with a downward first duct section and an upward second duct section, respectively in the direction of gravity and in the venting direction. When a gas exchange valve is closed, a lowermost section of the siphon is below a boundary of a pressure chamber defined by a slave piston.