A method for varying a compression ratio of an operating applied-ignition internal combustion engine having at least two cylinders and having a crank mechanism (1) comprising a crankshaft (2) which is mounted in a crankcase and which rotates at a crankshaft rotational speed .sub.crankshaft, is described. The method includes increasing an expansion phase of a cylinder cycle via rotation of the eccentric bushing (4).

A connection rod coupling assembly includes a settable shape mounting second component having a lateral, primary axis and a bearing assembly including a bearing assembly body. The bearing assembly body includes a substantially cylindrical outer surface and a center axis. The bearing assembly body is coupled to the settable shape mounting second component in a non-aligned configuration. That is, the bearing assembly body center axis is offset from the settable shape mounting second component primary axis. Thus, the position of the bearing assembly body center axis is adjustable by repositioning the settable shape mounting second component relative to a settable shape mounting first component on a swing lever. The adjustment of the bearing assembly body, in turn, adjusts the range of the ram assembly and the ram assembly body.

A connection rod coupling assembly includes a settable shape mounting second component having a lateral, primary axis and a bearing assembly including a bearing assembly body. The bearing assembly body includes a substantially cylindrical outer surface and a center axis. The bearing assembly body is coupled to the settable shape mounting second component in a non-aligned configuration. That is, the bearing assembly body center axis is offset from the settable shape mounting second component primary axis. Thus, the position of the bearing assembly body center axis is adjustable by repositioning the settable shape mounting second component relative to a settable shape mounting first component on a swing lever. The adjustment of the bearing assembly body, in turn, adjusts the range of the ram assembly and the ram assembly body.

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.

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.

A variable compression ratio engine comprises a stationary engine block in which movable members interact to enable a piston to translate in a combustion cylinder of the engine block, defining a stroke of the combustion piston. The engine further comprises a self-contained device for adjusting a position of a top dead center of the combustion piston, the self-contained device being connected to or built into at least one of the movable members and having a high-pressure hydraulic chamber to counteract the combustion and inertial forces at a bottom dead center, a low-pressure hydraulic chamber to counteract the inertial forces at the top dead center, at least one calibrated conduit to enable hydraulic fluid to flow between the high- and low-pressure hydraulic chambers, and return means to bring the device back to a nominal position.

A variable compression ratio engine comprises a stationary engine block in which movable members interact to enable a piston to translate in a combustion cylinder of the engine block, defining a stroke of the combustion piston. The engine further comprises a self-contained device for adjusting a position of a top dead center of the combustion piston, the self-contained device being connected to or built into at least one of the movable members and having a high-pressure hydraulic chamber to counteract the combustion and inertial forces at a bottom dead center, a low-pressure hydraulic chamber to counteract the inertial forces at the top dead center, at least one calibrated conduit to enable hydraulic fluid to flow between the high- and low-pressure hydraulic chambers, and return means to bring the device back to a nominal position.

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 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.

An adjustment device for adjusting several guide vanes of the engine, wherein the adjustment device includes at least one adjusting element that couples with the guide vanes and is mounted in an adjustable manner, a connection element that couples with the adjusting element, as well as a crank shaft for controlling an adjusting movement of the adjusting element, and the crank shaft has at least one coupling element which couples with the connection element and at which the connection element is hinged to transform a rotational movement of the crank shaft about a longitudinal axis of the crank shaft into an adjusting movement of the adjusting element for adjusting the guide vanes. The crank shaft has a modular design with at least two shaft modules that are arranged behind each other along the longitudinal axis of the crank shaft.