An ignition assembly configuration in piston engine with a main piston and an auxiliary piston, the ignition assembly is mounted on the cylinder wall and connects to the combustion chamber; the ignition assembly comprises an connection cut-out passage, an ignition device, or ignition device combined with a fuel injection nozzle, or an ignition device combined with a fuel injection nozzle and a pressure sensor passage. Wherein the auxiliary piston has a by-pass passage to keep the ignition assembly connected to the combustion chamber when the auxiliary piston moves down below the uppermost position of the main piston and blocks the ignition assembly cut-out passage; wherein the uppermost position of the ignition assembly is at or aligned with the uppermost position of the auxiliary piston in combustion stroke, the lowermost position of the ignition assembly is at or aligned with the uppermost position of the main piston. Fuel-water injection, multiple fuel injections and combustions can be easily practiced in the new configuration.

An internal combustion engine comprises a variable compression ratio mechanism that changes the relative position of a cylinder block with respect to a crankcase and a controlling device that controls the variable compression ratio mechanism. The variable compression ratio mechanism contains a driving device that rotates a shaft that includes an eccentric axis, and the drive device includes a clutch that blocks reverse input and is disposed in a drive power transmission route that transmits the rotational power of a motor to the shaft. The control device fixes the mechanical compression ratio to a predetermined low mechanical compression ratio when the amplitude of the rotational power vibration applied to an output shaft of the clutch is less than a predetermined determination value.

An endless band drive system having a variable center distance between the drive pulley and the driven pulley also has a rotatable control shaft and an endless band guide, where the guide is positioned by the rotatable control shaft for maintaining a slackless endless band with change of pulley center distance. Rotation of the control shaft pivots the endless band guide thereby maintaining a slackless endless band with change of the pulley center distance. Preferably, the rotatable control shaft also provides means for adjusting the center distance between the drive pulley and the driven pulley. The present invention provides a slackless endless band system for a variable compression ratio engine having a variable center distance between the drive pulley mounted on the crankshaft and the driven pulley mounted on the camshaft. The system provides slackless operation of the endless band at two or more compression ratio values.

An internal combustion engine including a block movement mechanism comprising a single control shaft extending in parallel with the crankshaft and supported by one of a crankcase and cylinder block and having a main shaft part and eccentric parts with an axial center at a position offset by a predetermined amount from the axial center of the main shaft part, coupling members with one end parts attached to the eccentric parts and the other end parts attached to the other of the crankcase and cylinder block and connecting the control shaft and the other of the crankcase and cylinder block, and an actuator making the control shaft rotate in both directions within a predetermined range of rotation so as to make the axial center of the eccentric parts swing about the axial center of the main shaft part in the direction of relative movement of the cylinder block.

An internal combustion engine provided with a cylinder block which can move relative to a crankcase is provided with a block movement mechanism arranged at just one side of the left and right of the internal combustion engine, a support member supporting a side surface of the cylinder block, and a pushing member pushing against a side surface of the cylinder block at the opposite side to the side surface supported by the support member. Further, the support member supports the side surface of the cylinder block at the side of arrangement of the block movement mechanism, while the pushing member pushes against the side surface of the cylinder block at the opposite side to the side of arrangement of the block movement mechanism.

A variable compression ratio mechanism of an internal combustion engine includes an operation element, an input actuator, and a reverse input torque cutoff clutch. The reverse input torque cutoff clutch includes a fixed member, a movable member, clearance, a wedge member, and a moving device. A peripheral surface of the fixed member is formed such that the clearance is formed with: a rotation prevention area that prevents the movable member from rotating in a reverse input torque acting direction. When the movable member moves in the direction to change a mechanical compression ratio, the moving device moves the wedge member from the rotation prevention area to the rotation allowable area in an opposite direction and holds the wedge member in the rotation allowable area.

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.

Improvements in a mechanism that determines top dead center of an internal combustion engine where detecting the top of the stroke can be difficult to determine as the crank is being rotated. The gauge set mounts into a spark plug or fuel injector hole. These holes are usually a tapped hole where the piston position gauge can be threaded into, to provide a stable and concentric mount where the measurement pin passes through the exterior threaded shaft of the mount. A pin extends into the cylinder to determine when the piston is approaching and at the top of the cylinder. The mount is an elongated stalk that allows for additional cam gauges where the cam gauges can be mounted and linearly adjustable on the single stalk. The measurement is with dial indicators so a user can measure three varying engine parts to determine the top-dead-center.

Presented are variable compression ratio and independent compression and expansion engines, methods for making/operating such engines, and vehicles equipped with such engines. An engine assembly includes an engine block with a cylinder bore defining a combustion chamber, and a piston movable within the cylinder bore. A valve assembly, which is fluidly coupled to the combustion chamber, selectively introduces/evacuates fluid from the combustion chamber. A crankshaft is supported by the engine block and rotatable on a first axis. A multipoint linkage, which drivingly engages the piston to the crankshaft, rotates on a second axis offset from the first axis. A control shaft is supported by the engine block and rotates on a third axis offset from the first and second axes. The control shaft operable to selectively rotate the multipoint linkage on the second axis, and is operable to selectively unseat the valve assembly.