A control method for an internal combustion engine is arranged to vary an engine compression ratio, and includes a control mechanism arranged to control the engine compression ratio, and a driving source arranged to drive the control mechanism. The control method includes converting an operation amount of the driving source in accordance with an attenuation rate according to the engine compression ratio, transmitting the converted operation amount to the control mechanism, and controlling the cylinder pressure based on a basic ignition timing when the attenuation rate is relatively large, and controlling the cylinder pressure based on an allowable ignition timing retarded from the basic ignition timing when the attenuation rate is relatively small.

A variable compression ratio device configured to be incorporated into an internal combustion engine. The internal combustion engine including one or more cylinders housing pistons that are coupled to a crankshaft. The variable compression ratio device including rotation coupler assemblies formed by gears that have internal and external teeth that are disposed at distal ends of the crankshaft to cause the crankshaft to rotate, and two or more eccentrics configured to cause translation variations of the crankshaft. Where the two or more eccentrics are positioned on trunnions of the crankshaft before and after each connecting rod and respective balances, the translation variations are to be converted into rotation and transmitted to a toothed gear and to a flange of a flywheel, and the two or more eccentrics are aligned with corresponding gears to cause changes in translation of a position of the crankshaft.

A VCR apparatus may include a connecting rod at which a small end forming a hole having a circular shape to be rotatably connected with a piston pin moving together with the piston and a large end rotatably connected with a crank pin eccentrically arranged with respect to the crankshaft are formed; an eccentric cam concentrically arranged and rotatably disposed in the hole of the small end and configured so that the piston pin is eccentrically inserted thereinto and is rotatably connected therewith; a latching pin disposed in the small end to make a reciprocal rectilinear motion in a direction of rotation axis of the small end and operated to selectively latch the small end with the eccentric cam in one among at least two relative positions between the small end and the eccentric cam; and an acting oil passage formed at the connecting rod.

Methods and systems are provided for adjusting a compression ratio. In one example, a system may include rotating an eccentric ring of a crankshaft by flowing hydraulic fluid to first and second chambers to actuate the eccentric ring.

A variable compression ratio apparatus is provided and is installed within an engine rotating a crankshaft upon receiving combustion power of a mixture from a piston and changes a mixture compression ratio based on an engine driving condition. The apparatus includes a connecting rod at which a small end forming a circular aperture to be rotatably connected with a piston pin moving together with the piston, a larger end rotatably connected with a crankpin eccentrically arranged with respect to the crankshaft, and an acting oil passage formed to supply hydraulic pressure from the larger end to the small end, are formed. An eccentric cam is concentrically arranged and rotatably disposed in the small end aperture and the piston pin is eccentrically inserted thereinto and is rotatably connected therewith. A latching pin selectively latches the small end with the cam by supply of hydraulic pressure through the acting oil passage.

A phasing system for varying a rotational relationship between a first rotary component and a second rotary component includes a gear hub and a cradle rotor. A spider rotor is arranged between the gear hub and the cradle rotor to selectively lock and unlock relative rotation between the gear hub and the cradle rotor. A torsion spring is coupled between the gear hub and the cradle rotor to apply a torque load between the gear hub and the cradle rotor. A planetary actuator is coupled to the gear hub and the spider rotor. The planetary actuator is operable between a steady-state mode, in which relative rotation between the gear hub and the cradle rotor is inhibited, and a phasing mode, in which the planetary actuator receives a rotary input at a predetermined magnitude to selectively provide a relative rotation between the gear hub and the cradle rotor.

A variable compression ratio device is configured to be incorporated into an internal combustion engine. The internal combustion engine includes one or more cylinders housing pistons that are coupled to a crankshaft. The variable compression ratio device includes a rotation coupler assembly formed by gears that have internal and external teeth, the rotation coupler assembly being disposed at a distal end of the crankshaft to cause the crankshaft to rotate. Translation variations of the crankshaft are to be converted into rotation and transmitted to at least one of a toothed gear or a flange of a flywheel.

There is provided an R- table apparatus which freely movies one table on a plane in the forward-and-rearward and leftward-and-rightward directions and in the rotational direction. The R- table apparatus changes a horizontal distance between a center line of a main axis of a driving apparatus and the action point by elevating an elevating base, and a table is moved to an arbitrary position without rotating along a guide member.

An internal combustion engine includes a crankshaft and at least one piston coupled to the crankshaft for executing strokes in a cylinder as a result of rotation of the crankshaft. An eccentric shaft is coupled to the crankshaft and to the piston in such a way that strokes of the piston are adjusted by the eccentric shaft. A phase adjuster adjusts a phase of the coupling of the eccentric shaft to the crankshaft.

As disclosed herein, a piston arrangement may include a cylinder, a piston head movable along a piston axis within the cylinder, a con rod, and a track. The con rod has a first end which is coupled to the piston head and a second end which is coupled to the track. The track is adapted to be moved relative to the cylinder and is shaped such that, as the track moves relative to the cylinder, the piston head moves in reciprocating motion along the piston axis in accordance with a path of the track. The path of the track may be shaped such that piston head displacement is non simple harmonic with respect to displacement of the track relative to the cylinder.