A continuous variable valve duration apparatus may include: a camshaft; first and second cam portions on which a cam is formed respectively; first and second inner brackets transmitting rotation of the camshaft to the first and second cam portions respectively; a slider housing in which the first and the second inner brackets are rotatably inserted; first and second guiding portions formed on the slider housing; a control shaft parallel to the camshaft; a control rod eccentrically formed on the control shaft; a positioning protrusion connected to the control shaft; a guide head on which a head guiding portion and a head hole are formed; a cam cap supporting rotations of the first and the second cam portions and guiding movement of the slider housing, a control portion selectively rotating the control shaft; and a stopper unit limiting movement of the positioning protrusion.

An electromagnetic actuator (1) includes sensor magnets (21a, 21b) disposed correspondingly to plungers (11a, 11b), respectively. The electromagnetic actuator (1) further includes a sensor core (22) made of a magnetic material and disposed in a position through which magnetic fluxes from the plurality of sensor magnets (21a, 21b) can flow, and a magnetic sensor (23) that is disposed in a part of the sensor core (22) through which the magnetic fluxes of the plurality of sensor magnets (21a, 21b) can flow in common, and that detects the magnetic flux, which varies in accordance with respective positions of the plurality of plungers (11a, 11b).

A continuous variable valve duration apparatus may include: a camshaft; first and second cam portions on which a cam is formed respectively; first and second inner brackets transmitting rotation of the camshaft to the first and second cam portions respectively; a slider housing in which the first and the second inner brackets are rotatably inserted; first and second guiding portions formed on the slider housing; a control shaft parallel to the camshaft; a control rod eccentrically formed on the control shaft; a positioning protrusion connected to the control shaft; a guide head on which a head guiding portion and a head hole are formed; a cam cap supporting rotations of the first and the second cam portions and guiding movement of the slider housing, a control portion selectively rotating the control shaft; and a stopper unit limiting movement of the positioning protrusion.

Embodiments of the disclosure provide variable valve timing (VVT) mechanisms. A VVT mechanism according to the disclosure can include: a lever having a first end, a second end, and a fulcrum positioned therebetween; a length-adjustable push rod coupled to the first end of the lever and including an actuator therein; a rod valve coupled to the second end of the lever, the rod valve being configured to open and close an intake valve of an engine system based on a movement of the lever; and an engine control unit (ECU) operatively connected to the actuator of the length-adjustable push rod, wherein the ECU adjusts a length of the length-adjustable push rod based on an operating condition of the engine system. In addition or alternatively, the ECU can control an amount of cushioning fluid for the valves to affect the rate at which the intake valve opens or closes.