Abstract: A variable valve lift apparatus to vary lift of a valve disposed at an engine may include an outer body selectively making a lever motion according to rotation of a cam, being adapted such that the valve is connected with one end thereof and a pivot axis of the lever motion is disposed at another end thereof, and forming an inside space, an inner body disposed in the inside space of the outer body and adapted such that one end thereof is rotatably connected with the one end of the outer body, a connecting shaft disposed so as to penetrate the one end of the outer body and the one end of the inner body and connect the outer body with the inner body, and a lost motion spring provided so as to return the inner body which is relatively rotated with the outer body around the connecting shaft.

Abstract: A variable compression ratio engine includes a variable chamber housing in fluidic communication with a combustion chamber of the engine, a chamber plunger slidably disposed within the variable chamber housing and forming a variable chamber together with the variable chamber housing, a hydraulic pressure cylinder connected with the variable chamber housing, a hydraulic piston slidably disposed within the hydraulic pressure cylinder, having a slider protruded to form first and second operation chambers with the hydraulic pressure cylinder and connected with the chamber plunger, a control plunger connected with the hydraulic piston, a control cylinder for receiving the control plunger and slidable with respect to the control plunger, a compression ratio control portion selectively moving the control cylinder along the length direction, and hydraulic pressure lines supplying control hydraulic pressure to the first or second operation chamber or releasing the control hydraulic pressure from the first or second op

Abstract: A variable valve lift apparatus to vary lift of a valve disposed at an engine may include an outer body selectively making a lever motion according to rotation of a cam, being adapted such that the valve is connected with one end thereof and a pivot axis of the lever motion is disposed at another end thereof, and forming an inside space, an inner body disposed in the inside space of the outer body and adapted such that one end thereof is rotatably connected with the one end of the outer body, a connecting shaft disposed so as to penetrate the one end of the outer body and the one end of the inner body and connect the outer body with the inner body, and a lost motion spring provided so as to return the inner body which is relatively rotated with the outer body around the connecting shaft.

Abstract: A variable compression ratio apparatus mounted on an engine configured to receive combustion force of a mixer from a piston to rotate a crankshaft, and configured to change a compression ratio of the mixer may include an eccentric bearing assembly connected with the piston through a piston pin, and including an eccentric ring including an eccentric hole through which the piston pin passes so that the piston pin may be rotatably installed while being eccentric to the eccentric ring, and an eccentric link connected to the eccentric ring to transfer rotation force thereof to the eccentric ring, a connecting rod including one end provided with a mounting hole into which the eccentric ring may be rotatably inserted, a central portion provided with an operation hole, wherein the eccentric link may be movable through the operation hole, and the other end rotatably connected to the crankshaft while being eccentric to the crankshaft, and a control shaft connected to the eccentric link and configured to rotate the ecce

Abstract: A variable compression ratio device may include a piston assembly having double pistons of which the volume may be varied, a lifter relatively moving one piston of the double pistons with respect to the other piston of the double pistons, a guide unit engaged with the piston assembly and guiding a movement of the one piston with respect to the other piston, and a locking unit selectively coupling the one piston to the other piston.

Abstract: A variable compression ratio engine that changes the compression ratio may include a piston disposed to be reciprocated in a cylinder by combustion, a crankshaft rotatably disposed at a predetermined distance from the piston, a crank arm with one end connected with the piston and the other end connected with the crankshaft, a connecting rod connected with the crank arm through a crankpin and with the piston through a piston pin and having an oil chamber, an eccentric cam disposed between the crankpin and the connecting rod and being off-center from the crankpin, a variable piston disposed in the oil chamber to be moved by supplied oil, and a link connecting the variable piston with the eccentric cam to rotate the eccentric cam with movement of the variable piston.

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 compression ratio engine includes a variable chamber housing in fluidic communication with a combustion chamber of the engine, a chamber plunger slidably disposed within the variable chamber housing and forming a variable chamber together with the variable chamber housing, a hydraulic pressure cylinder connected with the variable chamber housing, a hydraulic piston slidably disposed within the hydraulic pressure cylinder, having a slider protruded to form first and second operation chambers with the hydraulic pressure cylinder and connected with the chamber plunger, a control plunger connected with the hydraulic piston, a control cylinder for receiving the control plunger and slidable with respect to the control plunger, a compression ratio control portion selectively moving the control cylinder along the length direction, and hydraulic pressure lines supplying control hydraulic pressure to the first or second operation chamber or releasing the control hydraulic pressure from the first or second op

Abstract: A variable compression ratio engine that changes the compression ratio may include a piston disposed to be reciprocated in a cylinder by combustion, a crankshaft rotatably disposed at a predetermined distance from the piston, a crank arm with one end connected with the piston and the other end connected with the crankshaft, a connecting rod connected with the crank arm through a crankpin and with the piston through a piston pin and having an oil chamber, an eccentric cam disposed between the crankpin and the connecting rod and being off-center from the crankpin, a variable piston disposed in the oil chamber to be moved by supplied oil, and a link connecting the variable piston with the eccentric cam to rotate the eccentric cam with movement of the variable piston.

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 CDA device includes: an outer body that moves up/down in contact with a cam and has an oil input hole at one side and latching pin chambers; an upper seat disposed inside the outer body; an inner body disposed slidably inside the outer body, has a latching pin hole, and is combined with a valve; a lost motion spring that elastically supports the outer body in a lost motion between the inner body and the outer body; latching pins that are slidably disposed in the latching pin chambers and inserted in the latching pin holes; and latching pin springs that push the latching pins into the latching pin hole, in which hydraulic pressure selectively transmitted from the oil input hole pushes the latching pins and the latching pins are separated from the latching pin holes.

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 compression ratio device may include a piston assembly having double pistons of which the volume may be varied, a lifter relatively moving one piston of the double pistons with respect to the other piston of the double pistons, a guide unit engaged with the piston assembly and guiding a movement of the one piston with respect to the other piston, and a locking unit selectively coupling the one piston to the other piston.

Abstract: A variable compression ratio (VCR) apparatus, may include a piston, a connecting rod having one end coupled to the piston through a piston pin so as to transmit a motion of the piston to a crank shaft, a pair of first and second eccentric links having one ends eccentrically connected to the one end of the connecting rod through the piston pin, dual swing links having one ends connected to the other ends of the first and second eccentric links, respectively, so as to pivot the eccentric links with respect to the piston pin, and connecting assembly connecting the one ends of the first and second eccentric links each other.

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 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 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 (VCR) apparatus with dual eccentric links is mounted on an engine, receives combustion power of a fuel-air mixture from a piston to rotate a crank shaft and changes a compression ratio of the fuel-air mixture. The VCR apparatus may include a connecting rod having a large end portion formed at one end thereof, which is connected to the crank shaft to receive a torque of the engine, and a small end portion formed at the other end thereof, the small end portion having a coupling hole formed therein, a pair of eccentric links having one ends coupled to the coupling hole from both sides facing each other and integrally rotating, and an eccentric rod connected to the other ends of the eccentric links and rotating within a predetermined angle range. The eccentric rod may be a pair of eccentric rods.

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 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.