Abstract: A multiple variable valve lift apparatus has a simple design that efficiently operates without interference. The apparatus according may include: a camshaft formed in a hollow cylinder shape; a control shaft disposed in the hollow of the camshaft; a cam that rotates together with the camshaft; a cam rod connecting the control shaft with the cam to move together; an operating unit disposed on the exterior circumference of the camshaft to rotate together with the camshaft; an operating unit rod connecting the control shaft with the operating unit such that the control shaft and the operating unit move together; a solenoid selectively connected with the operating unit, and moving the operating unit along an axial direction of the camshaft; and a tappet contacting the cam to transform rotational motion of the cam to rectilinear motion of a valve.

Abstract: Disclosed is a variable compression ratio control system configured to change a top dead center of a piston in an engine according to an operation state of the engine. The control system may include a motor provided as a power source, a control shaft coupled to the piston, wherein the control shaft changes the top dead center of the piston by a rotation of the control shaft, a driving shaft connected to the motor and to be rotated by the motor, an operation unit movable in a shaft direction of the driving shaft by a rotation of the driving shaft, and an operation link protruding from one portion of an exterior circumferential surface of the control shaft, wherein the operation unit is connected with the operation link so that the operation link rotates the control shaft while the operation unit moves in the shaft direction of the driving shaft.

Abstract: A variable valve lift apparatus may include an outer tappet body of which a latching portion connecting hole and an outer tappet body guide hole may be formed therewithin, an inner tappet body of which an inner tappet body guide hole may be formed therewithin and slidably disposed within the outer tappet body, a latching portion which may be disposed within the inner tappet body guide hole and selectively coupled to the latching portion connecting hole, a latching portion support pin which guides the latching portion along a longitudinal direction of the inner tappet body guide hole and may be connected to the inner tappet body, a hydraulic pressure chamber, and a plunger which may be slidably disposed in the outer tappet body guide hole and selectively inserts the latching portion into the latching portion connecting hole according to the hydraulic pressure supplied from the hydraulic pressure chamber.

Abstract: A variable compression ratio apparatus mounted on an engine may include an eccentric bearing assembly engaged with the piston through a piston pin, and including an eccentric ring having an eccentric hole so that the piston pin may be rotatably installed therethrough while being eccentric to the eccentric ring, and an eccentric link connected to the eccentric ring to transfer rotation force to the eccentric ring, a first connecting rod rotatably installed at an one side in an axial direction of the eccentric ring, a second connecting rod rotatably installed at the other side in the axial direction of the eccentric ring, and a control shaft connected to the eccentric link to rotate the eccentric bearing assembly by transferring the rotation force to the eccentric ring.

Abstract: A multiple variable valve lift apparatus may include a camshaft, a plurality of cams slidably fitted on the camshaft and each having a cam base with a guide groove and a cam lobe, a solenoid valve including an actuating rod capable of being selectively inserted into the guide groove of a cam in the plurality of cams, and a valve opening/closing unit capable of selectively coming in contact with any cam in the plurality of cams.

Abstract: A spark ignition engine includes a main combustion chamber configured to suction a mixture through an intake port, a pre-chamber configured to communicate with the main combustion chamber, an auxiliary cylinder configured to communicate with the main combustion chamber via the pre-chamber, an auxiliary intake passage connecting the auxiliary cylinder and the intake port, an auxiliary piston, and a spark plug configured to ignite the mixture in the pre-chamber. The auxiliary piston is configured to slidably reciprocate in the auxiliary cylinder such that the mixture is suctioned from the intake port via the auxiliary intake passage and the mixture is discharged to the main combustion chamber via the pre-chamber.

Abstract: A variable cycle engine may include a first cylinder that performs an intake, a compression, an explosion, or an exhaust stroke, a second cylinder that performs an intake, a compression, an explosion, or an exhaust stroke, a connection rail that is formed near the first cylinder and the second cylinder, a first variable port that is diverged from one side of the connection rail and is connected to the first cylinder, a second variable port that is diverged from the other side of the connection rail and is connected to the second cylinder, and a first variable control valve disposed on the first variable port and a second variable control valve disposed on the second variable port, wherein the first and second variable control valves are opened or closed accordingly with respect to each other to directly connect the first cylinder with the second cylinder.

Abstract: A variable compression ratio apparatus may include a crankshaft, a connecting rod, first and second eccentric links mounted at both sides of the connection rod, respectively, and having one ends at which the piston pin may be eccentrically and rotatably installed, a swing link of which one end may be branched into two parts to form first and second branches, the first and second branches being connected to the other ends of the first and second eccentric links, and a control device connected to the other end of the swing link to control the swing link, wherein the crank arm includes guide surfaces formed in a predetermined thickness at an inner circumferential surface of the crank arm so that the first and second branches of the swing link slide to move between the guide surfaces.

Abstract: A variable valve lift apparatus may include a camshaft, a low lift cam which may be connected to the camshaft and rotates, a high lift cam which may be rotatably mounted to the camshaft and may be selectively connected to the camshaft to rotate with the camshaft, a high lift cam connecting portion which selectively connects the high lift cam to the camshaft, and a tappet including a low lift cam contact portion contacting the low lift cam and a high lift cam contact portion selectively activating the high lift cam.

Abstract: A variable compression ratio apparatus may include a connecting rod having a small end portion having an eccentric bearing installation hole, a large end portion rotatably connected to the crank shaft, and a space portion formed in a longitudinal direction of the connecting rod and communicated with the eccentric bearing installation hole, a piston pin fixedly, an eccentric bearing rotatably engaged to the eccentric bearing installation hole and coupled to the piston pin through a pin installation hole of the eccentric bearing, wherein the piston pin may be offset from a center axis of the eccentric bearing, an eccentric link connected to the eccentric bearing, a variable link rotatably connected to the eccentric link, a control link rotatably connected to the variable link, and a control shaft provided in the control link to rotate the control link, wherein the eccentric link may be rotated within the space portion.

Abstract: A variable compression ratio apparatus may include a crankshaft, a connecting rod, first and second eccentric links mounted at both sides of the connection rod, respectively, and having one ends at which the piston pin may be eccentrically and rotatably installed, a swing link of which one end may be branched into two parts to form first and second branches, the first and second branches being connected to the other ends of the first and second eccentric links, and a control device connected to the other end of the swing link to control the swing link, wherein the crank arm includes guide surfaces formed in a predetermined thickness at an inner circumferential surface of the crank arm so that the first and second branches of the swing link slide to move between the guide surfaces.

Abstract: An electric motor includes: an electric motor case shaped like a cylinder; an electric motor shaft rotatably provided at a center of the electric motor case; a magnet provided at an inner circumferential surface of the electric motor case; a coil provided to correspond to the magnet; a brush provided between the coil and the electric motor shaft and connected with an external power to transmit current of the external power; and a commutator configured to receive power from the brush and supply the received power to the coil.

Abstract: A pre-chamber structure for a piston engine may include: a pre-chamber combustion chamber in which a mixture of fuel and air is combusted and a pre-chamber compression chamber including a sub-chamber communicating with the pre-chamber combustion chamber and having an inclined wall surface, and a main chamber extending from the sub-chamber, thereby preventing the fuel from being adsorbed and remaining in the wall surface of the pre-chamber compression chamber in a droplet state.

Abstract: A variable compression ratio apparatus includes: a piston defining a combustion chamber, a connecting rod connected to the piston; an eccentric link eccentrically connected to the piston, a swing link connected to the eccentric link so as to rotate the eccentric link, a crankpin to which the connecting rod is connected, and a crank web disposed at both sides of the crankpin and provided with a guide portion for guiding downward motions of the eccentric link and the swing link when the eccentric link and the swing link move downward. Thereby, the downward motions of the eccentric link and the swing link are stabilized.

Abstract: A continuous variable valve lifter having a cylinder air volume difference adjuster includes a camshaft having an input cam, an eccentric control shaft disposed parallel to the camshaft, and a control link rotatable around the eccentric control shaft. An output cam is provided to open and close a valve actuator for opening/closing, and a connection link is rotatably connected to the control link, and driving the output cam by the rotation of the input cam. A cam cap is disposed where the camshaft and the eccentric control shaft are mounted. The cylinder air volume difference adjuster includes a hinge pin serving as the rotational center of the output cam disposed parallel to the camshaft, a pin holder where the hinge pin is mounted, and an adjusting bolt for selectively shifting the position of the pin holder.

Abstract: An engine may include a crankshaft, a piston, a connecting rod that connects a crank pin of the crankshaft with the piston, and a compression ratio variable device that varies a distance between the piston and the crank pin, wherein the compress ratio variable device includes: a block cover mounted on an outside of the engine block and a cover journal portion and a worm wheel mounting space are formed therein, a control shaft contacting the cover journal portion and an operating arm protruding from an exterior circumference of the control shaft, and a motor portion, wherein a worm connected to the motor portion is mounted to the block cover, the worm being engaged with the worm wheel so as to rotate the control shaft according to the motor portion, wherein a distance between the piston and the crank pin is varied by a rotation of the control shaft.

Abstract: An electro-hydraulic variable valve lift apparatus may include an hydraulic pump body installed in an engine, a piston provided to reciprocate within the hydraulic pump body and forming an hydraulic pump chamber together with the hydraulic pump body, an hydraulic pump cam disposed to be in contact with the piston and enabling the piston to reciprocate according to a rotation thereof, a retainer provided to be slidable along the piston between the piston and the engine and forming a retainer chamber with the engine, a retainer spring elastically supporting the retainer, an oil control valve allowing the hydraulic pump chamber and the retainer chamber to selectively communicate with each other, a valve opening and closing unit communicating with the hydraulic pump chamber and opened or closed according to oil pressure supplied from the hydraulic pump chamber.

Abstract: A variable compression ratio apparatus may include a cylinder block and a mounting hole formed at a side surface thereof; a connecting rod pivotally connected to the piston; a crankshaft provided with a central axis, a bearing seat coaxially disposed with the central axis, and a crank pin formed in a crank arm connecting the bearing seat with the central axis of the crank pin eccentrically, wherein the crank pin is rotatably connected to the connecting rod; and an eccentric bearing provided with a bearing central axis and a crank mounting hole formed eccentrically to the bearing central axis, the crank mounting hole of the eccentric bearing being rotatably coupled to the bearing seat rotatably inserted in the crank mounting hole, wherein the eccentric bearing changes the compression ratio by controlling a distance between the central axis and a combustion chamber according to driving condition of the vehicle.

Abstract: An electro-hydraulic variable valve lift apparatus includes a housing, a driving cam, a pump piston which forms a main chamber with the housing, reciprocates within the housing according to rotation of the driving cam, and forms hydraulic pressure within the main chamber, a pump piston elastic portion disposed for elastically supporting the pump piston, an oil pressure controller communicating with the main chamber in order to control hydraulic pressure within the main chamber, a hydraulic piston slidably disposed within the housing, includes a first body having a first diameter and a second body having a second diameter larger than the first diameter, and is connected with a valve, and a piston guide disposed between the housing and the hydraulic piston for guiding the hydraulic piston.

Abstract: A continuously variable valve timing apparatus may include an end plate connected to a camshaft, a drive sprocket rotating the end plate, a first friction plate disposed to be coaxial to the end plate, a second friction plate disposed to be coaxial to the end plate, a first brake selectively braking the first friction plate, a second brake selectively braking the second friction plate, and a control gear portion which changes relative phase between the end plate and the drive sprocket according to braking of the first friction plate or the second friction plate.