A system and method for providing a variable compression ratio internal combustion engine is disclosed. The system can include a plurality of hollow head bolts for coupling the cylinder head and block of an internal combustion engine. The system can also include a plurality of control bolts disposed through the hollow head bolts to enable vertical movement of the engine components (i.e., in the y-axis), while reducing, or eliminating, unwanted movement and stresses in other directions. A number of mechanisms can be used to move the cylinder head/block assembly, including a rack and pinion, a hydraulic or pneumatic actuator, and a gear drive. The compression ratio can be varied continuously during use and can be included in an overall engine management system.

A system and method for providing a variable compression ratio internal combustion engine is disclosed. The system can include a plurality of hollow head bolts for coupling the cylinder head and block of an internal combustion engine. The system can also include a plurality of control bolts disposed through the hollow head bolts to enable vertical movement of the engine components (i.e., in the y-axis), while reducing, or eliminating, unwanted movement and stresses in other directions. A number of mechanisms can be used to move the cylinder head/block assembly, including a rack and pinion, a hydraulic or pneumatic actuator, and a gear drive. The compression ratio can be varied continuously during use and can be included in an overall engine management system.

The present disclosure relates to a system for controlling ignition of an air/fuel mixture intake charge directed into an internal combustion engine. The system may have a longitudinally movable inner cylinder liner configured to fit within a cylinder wall portion of an internal combustion engine, and able to receive a piston of the engine therein. A portion of the inner cylinder liner defines an internal volume forming a combustion chamber, and the internal volume controls a compression ratio of the cylinder. The system also has a cylinder head assembly operatively associated with the inner cylinder liner and able to move linearly to cause longitudinal displacement of the inner cylinder liner relative to the cylinder wall portion. This enables the volume of the combustion chamber to be further varied, to thus further vary the compression ratio.

The present disclosure relates to a system for controlling ignition of an air/fuel mixture intake charge directed into an internal combustion engine. The system may have a longitudinally movable inner cylinder liner configured to fit within a cylinder wall portion of an internal combustion engine, and able to receive a piston of the engine therein. A portion of the inner cylinder liner defines an internal volume forming a combustion chamber, and the internal volume controls a compression ratio of the cylinder. The system also has a cylinder head assembly operatively associated with the inner cylinder liner and able to move linearly to cause longitudinal displacement of the inner cylinder liner relative to the cylinder wall portion. This enables the volume of the combustion chamber to be further varied, to thus further vary the compression ratio.

Methods and systems are provided for synergizing the benefits of a variable compression ratio engine in a hybrid vehicle system. A vehicle controller may hold the engine in a lower compression ratio during engine pull-ups and pull-downs, in particular when passing through a low speed region where compression bobbles can occur. During engine operation, in response to a change in driver demand, the controller may opt to switch the compression ratio or maintain a current compression ratio while smoothing a torque deficit using motor torque, the selection based on fuel economy.

Methods and systems are provided for synergizing the benefits of a variable compression ratio engine in a hybrid vehicle system. A vehicle controller may hold the engine in a lower compression ratio during engine pull-ups and pull-downs, in particular when passing through a low speed region where compression bobbles can occur. During engine operation, in response to a change in driver demand, the controller may opt to switch the compression ratio or maintain a current compression ratio while smoothing a torque deficit using motor torque, the selection based on fuel economy.

A system is provided for an internal combustion engine including at least two cylinders, wherein the at least two cylinders form at least two groups, wherein each group has at least one cylinder, the at least one cylinder of at least one group being formed as a cylinder which can be activated in a load-dependent manner and which is deactivated if a predefined load is undershot. The at least two groups are characterized by different cylinder volumes, the at least one cylinder of a first group having a lesser cylinder volume and the at least one cylinder of a second group having a greater cylinder volume and configured as an activatable cylinder.

A system is provided for an internal combustion engine including at least two cylinders, wherein the at least two cylinders form at least two groups, wherein each group has at least one cylinder, the at least one cylinder of at least one group being formed as a cylinder which can be activated in a load-dependent manner and which is deactivated if a predefined load is undershot. The at least two groups are characterized by different cylinder volumes, the at least one cylinder of a first group having a lesser cylinder volume and the at least one cylinder of a second group having a greater cylinder volume and configured as an activatable cylinder.

The present invention concerns a method for providing a variable compression ratio in a combustion engine, where the combustion chamber (9) is formed substantially by a piston bowl in the main piston (1), comprising a secondary piston (3) being displaceable against spring action between an upper/outer position which provides minimal volume of the combustion chamber (9) and lower/inner position which provides maximum volume of the combustion chamber (9), or in a position therebetween depending on introduced air mass before the compression stroke. The method is characterized in arranging said secondary piston (3) resting on a spring (5) with substantially constant spring force adapted such that introduced air mass is to be compressed to a predetermined pressure at the end of the compression stroke. The invention also concerns a corresponding device and a diesel engine comprising such a device.

The present invention concerns a method for providing a variable compression ratio in a combustion engine, where the combustion chamber (9) is formed substantially by a piston bowl in the main piston (1), comprising a secondary piston (3) being displaceable against spring action between an upper/outer position which provides minimal volume of the combustion chamber (9) and lower/inner position which provides maximum volume of the combustion chamber (9), or in a position therebetween depending on introduced air mass before the compression stroke. The method is characterized in arranging said secondary piston (3) resting on a spring (5) with substantially constant spring force adapted such that introduced air mass is to be compressed to a predetermined pressure at the end of the compression stroke. The invention also concerns a corresponding device and a diesel engine comprising such a device.