An internal combustion may include a cylinder having a first combustion chamber at one end and a second combustion chamber at an opposing end, first and second cylinder heads located at an end of the first and second combustion chambers, respectively, and a double-faced piston slidably mounted therein. The piston may be configured to move in a first stroke that includes an expansion stroke portion and a non-expansion stroke portion. The engine may further include first and second piston rod portions extending from opposite faces of the piston. A recess in the piston rod portions may be configured to communicate gases between a combustion chamber and locations outside the cylinder. There may also be a chamber surrounding the first or second piston rod portion, the chamber configured to be supplied with gas and the chamber being isolated from the first combustion chamber and the second combustion chamber.

A rotary valve internal combustion engine has a piston connected to a crankshaft, where the piston is reciprocatable in a cylinder, and a combustion chamber being defined in part by the piston. The engine has a rotary valve rotatable in a valve housing fixed relative to the cylinder, the rotary valve having a valve body containing a volume defining, in part, the combustion chamber and further having in a wall part thereof a port giving, during rotation of the valve, fluid communication successively to and from the combustion chamber via inlet and exhaust ports in the valve housing. The valve body has a non-uniform radial profile along its axial length and/or about its axis of rotation to accommodate changes in the profile of the valve body during operation to maintain a substantially constant clearance between the valve body and the housing throughout the length of the valve body.

An electro-mechanical variable valve mechanism includes a variable valve mechanism body, a latching pin arranged in front of the variable valve mechanism body, and an inner body arranged inside the variable valve mechanism body. The latching pin reciprocates in a longitudinal direction of the variable valve mechanism body and the inner body to latch the variable valve mechanism body and the inner body.

An electro-mechanical variable valve mechanism includes a variable valve mechanism body, a latching pin arranged in front of the variable valve mechanism body, and an inner body arranged inside the variable valve mechanism body. The latching pin reciprocates in a longitudinal direction of the variable valve mechanism body and the inner body to latch the variable valve mechanism body and the inner body.

A volumetric expander (4) comprising a casing (50) having a general inlet and outlet (51, 52), a piston (6) operating inside the casing and adapted to define an expansion chamber (7) with variable volume, a main shaft (11) connected to the piston (6), and a valve (6) for selectively opening and closing an inlet and an outlet (8, 9) of the expansion chamber (7) allowing: a condition of introduction of the working fluid in the expansion chamber (7), a condition of expansion of the working fluid in the expansion chamber (7), and a condition of discharge of the working fluid from said expansion chamber (7). The expander comprises a transmission member (53) connected—on one side—to the valve (10) and—on the other side—to the main shaft (11). The casing (50) defines a discharge chamber in direct communication with the general outlet (52) and configured for being put in direct fluid communication with the outlet (9) of the expansion chamber (7) during the condition of discharging the working fluid from the expansion chamber (7) itself. The transmission member (53) is disposed in the casing (50) inside the working fluid discharge chamber. The casing (50) comprises an auxiliary inlet (59) which is only directly in communication with the discharge chamber of the casing (50) and through this latter, with the general outlet (52); the auxiliary inlet (59) is configured for enabling the working fluid to directly enter the casing (50).

A spark ignition rotary valve internal combustion engine includes a combustion chamber being defined in part by the piston and the combustion end of the cylinder, a valve housing fixed at an outer portion of the combustion end of the cylinder and defining a bore, and a rotary valve rotatable about a rotary valve axis in the bore in the valve housing. The rotary valve has a hollow valve body subjected to combustion gases throughout the combustion process. The rotary valve also has, in a wall part thereof, a port giving, during rotation of the valve, fluid communication successively to and from the combustion chamber via inlet and exhaust ports in the valve housing. The inlet and exhaust ports are angularly offset with respect to a radial line from the center of the engine cylinder.

A split-cycle engine includes: a first cylinder housing a first piston, wherein the first piston performs an intake stroke and a compression stroke, but does not perform an exhaust stroke; a second cylinder housing a second piston, wherein the second piston performs an expansion stroke and an exhaust stroke, but does not perform an intake stroke; and a valve chamber housing a valve, the valve comprising an internal chamber that selectively fluidly couples to the first and second cylinders, wherein the valve and internal chamber move within the valve chamber and relative to the first and second cylinders.

A split-cycle engine includes: a first cylinder housing a first piston, wherein the first piston performs an intake stroke and a compression stroke, but does not perform an exhaust stroke; a second cylinder housing a second piston, wherein the second piston performs an expansion stroke and an exhaust stroke, but does not perform an intake stroke; and a valve chamber housing a valve, the valve comprising an internal chamber that selectively fluidly couples to the first and second cylinders, wherein the valve and internal chamber move within the valve chamber and relative to the first and second cylinders.

An internal combustion may include a cylinder having a first combustion chamber at one end and a second combustion chamber at an opposing end, first and second cylinder heads located at an end of the first and second combustion chambers, respectively, and a double-faced piston slidably mounted within the cylinder. The piston may be configured to move in the cylinder in a first stroke from one end to another. The first stroke may include an expansion stroke portion and a non-expansion stroke portion. The non-expansion stroke portion may include a momentum stroke portion. The non-expansion stroke portion may include a scavenging phase. The engine may further include first and second piston rod portions extending from opposite faces of the piston. Passageways in the piston rod portions may be configured to communicate gases between a combustion chamber and other locations.

An internal combustion may include a cylinder having a first combustion chamber at one end and a second combustion chamber at an opposing end, first and second cylinder heads located at an end of the first and second combustion chambers, respectively, and a double-faced piston slidably mounted within the cylinder. The piston may be configured to move in the cylinder in a first stroke from one end to another. The first stroke may include an expansion stroke portion and a non-expansion stroke portion. The non-expansion stroke portion may include a momentum stroke portion. The non-expansion stroke portion may include a scavenging phase. The engine may further include first and second piston rod portions extending from opposite faces of the piston. Passageways in the piston rod portions may be configured to communicate gases between a combustion chamber and other locations.