Abstract: An engine includes an engine shaft and a piston configured to reciprocate within a cylinder chamber having an axis, each piston having an first piston part and piston stem to move in unison with or separately from a second piston part to define piston strokes for different thermal functions of the engine. The engine further includes a linkage assembly having a first end coupled to the engine and a second end coupled to the piston stem defining a copy point, an actuator that engages the linkage assembly, and a guide cam that engages a guide cam follower on the linkage assembly. The actuator and the guide cam are operable to control motion of the linkage assembly to thereby define substantially linear movement of the copy point along the cylinder chamber axis.

Abstract: An engine includes an engine shaft configured to rotate and cause one or more pistons to reciprocate within a cylinder chamber along an axis, each piston having a first piston part and piston stem to move in unison with or separately from a second piston part to define piston strokes for different thermal functions of the engine. The engine further includes a piston lever having a first end coupled to a movable fulcrum point and a second end coupled at a copy point to the piston stem, an actuation mechanism configured to move the piston lever and thereby the copy point, and a guide apparatus configured to dictate movement of the copy point in a direction substantially parallel to the cylinder axis.

Abstract: An internal combustion engine that includes a variable stroke piston is described. The described engine includes a variable valve timing system and optional variable compression ration system. In embodiments, an electronic control unit coordinates the operations of the variable stroke piston, variable valve timing system, and variable compression ratio system in order to optimize engine performance across a wide range of engine conditions.

Abstract: An engine includes an engine shaft configured to rotate and cause one or more pistons to reciprocate within a cylinder chamber along an axis, each piston having a first piston part and piston stem to move in unison with or separately from a second piston part to define piston strokes for different thermal functions of the engine. The engine further includes a piston lever having a first end coupled to a movable fulcrum point and a second end coupled at a copy point to the piston stem, an actuation mechanism configured to move the piston lever and thereby the copy point, and a guide apparatus configured to dictate movement of the copy point in a direction substantially parallel to the cylinder axis.

Abstract: A variable-stroke reciprocating internal combustion engine, the engine having an engine shaft and a piston configured to reciprocate within a cylinder chamber having an axis, each piston having a first piston part operable to move in unison with or separately from a second piston part to define piston strokes for different thermal functions of the engine, includes an assembly pivotally coupled to the first piston part at a copy point and an actuator coupled to the assembly, wherein the actuator is operable to control motion of the assembly to thereby define substantially linear movement of the copy point along the cylinder chamber axis.

Abstract: A variable-stroke reciprocating internal combustion engine, the engine having an engine shaft and a piston configured to reciprocate within a cylinder chamber having an axis, each piston having a first piston part operable to move in unison with or separately from a second piston part to define piston strokes for different thermal functions of the engine, includes an assembly pivotally coupled to the first piston part at a copy point and an actuator coupled to the assembly, wherein the actuator is operable to control motion of the assembly to thereby define substantially linear movement of the copy point along the cylinder chamber axis.