Intake holes at the opposite ends are opened and closed by first intake valves. The middle intake hole is opened and closed by a second intake valve. A control device includes an intake variable valve device. First branch channels are connected to the intake holes and produce a normal tumble flow. A second branch channel is configured such that the flow rate of intake air passing through the middle intake hole is relatively greater on the side closer to the outer periphery of the combustion chamber. Where increasing the flow coefficient is given a higher priority, a three-valve drive mode is selected. Where the strength of the normal tumble flow is enhanced, a two-valve drive mode is selected. Where production of the normal tumble flow is reduced, a one-valve drive mode is selected.

An electromagnetic actuator having at least one electromagnetic actuator unit, the actuator unit comprising a coil and a plunger, which plunger is axially movable relative to the coil via energization of the coil, and the actuator unit being arranged in a housing. In order to achieve a particularly simple design, the plunger is arranged approximately coaxially with the coil according to the invention.

A translating actuator acting between two extreme positions defined by mechanical stops is described. Said actuator comprises: an armature mass movable relative to the armature body, a stiff armature spring set such that the natural resting position of the armature mass is close to the centre of travel between the two extreme positions and pair of latches with sufficient holding force that the armature mass can be held at either extreme position against the restoring force of the spring and can be released quickly relative to the natural period of vibration determined by the armature mass on the armature spring.

The present invention concerns a method for electrically controlling a valve actuator in a 2-stroke or 4-stroke engine, where the actuator comprises a first solenoid (A) with a plunger (5) and a second solenoid (B) with a plunger (15), wherein the engine has at least one cylinder (1) with at least one freely controllable engine valve comprising a valve disc (10) with associated valve stem (11) and a valve spring (4) and where air is introduced, or exhaust gases are evacuated from, a combustion chamber (3) past a lower part of the valve stem with the valve disc via at least one channel (2) in the cylinder, wherein the valve actuator is activatable to open the engine valve. The invention is characterized in that both the first and second solenoid are activated during opening of the engine valve.

The system, according to one embodiment of the present invention, comprises a stationary coil linear motor to drive a valve with a stem comprising a ferromagnetic property. The linear motor moves the valve in response to control governed by an electronic valve control computer. The valve is movable between a closed position at a selectable rate of both acceleration and speed for a selectable distance (“lift”) to a second selectable open position, including all position variations between the fully open and fully closed states. Valve position, velocity and acceleration can be varied both during a valve stroke and from one stroke to the next, as controlled by the logic programmed on a non-transitive memory of the electronic valve control computer.

A linear motor actuated valve assembly in which a linear motor enables electrical actuation and control of intake and exhaust valves of an internal combustion engine.

The present invention concerns a method for electrically controlling a valve actuator in a 2-stroke or 4-stroke engine, where the actuator comprises a first solenoid (A) with a plunger (5) and a second solenoid (B) with a plunger (15), wherein the engine has at least one cylinder (1) with at least one freely controllable engine valve comprising a valve disc (10) with associated valve stem (11) and a valve spring (4) and where air is introduced, or exhaust gases are evacuated from, a combustion chamber (3) past a lower part the valve stem with the valve disc via at least one channel (2) in the cylinder, wherein the valve actuator is activatable to open the engine valve. The invention is characterized in that both the first and second solenoid are activated during opening of the engine valve.

An electromagnetic actuator having at least one electromagnetic actuator unit, the actuator unit comprising a coil and a plunger, which plunger is axially movable relative to the coil via energization of the coil, and the actuator unit being arranged in a housing. In order to achieve a particularly simple design, the plunger is arranged approximately coaxially with the coil according to the invention.

An apparatus includes a valve and an actuator. The valve has a portion movably disposed within a valve pocket defined by a cylinder head of an engine. The valve is configured to move relative to the cylinder head a distance between a closed position and an opened position. The portion of the valve defines a flow opening that is in fluid communication with a cylinder of an engine when the valve is in the opened position. The actuator is configured to selectively vary the distance between the closed position and the opened position.

Linear actuators are disclosed. The linear actuator comprises a thruster and a stator. The thruster includes a thruster winding, and the stator includes a stator winding. The stator is disposed about the thruster. The linear actuator also includes a sheath disposed about the stator and the thruster. The thruster is configured to translate within the sheath relative to the stator upon application of an electrical current to the stator winding, the thruster winding, or a combination thereof. The stator winding and the thruster winding each comprise a nonpermanent magnet.