A volumetric expander comprising a casing having a general inlet and outlet, a piston operating inside the casing and adapted to define an expansion chamber with variable volume, a main shaft connected to the piston, and a valve for selectively opening and closing an inlet and an outlet of the expansion chamber allowing: a condition of introduction of the working fluid in the expansion chamber, a condition of expansion of the working fluid in the expansion chamber, and a condition of discharge of the working fluid from said expansion chamber. The casing defines a discharge chamber in direct communication with the general outlet and configured for being put in direct fluid communication with the outlet of the expansion chamber during the condition of discharging the working fluid from the expansion chamber itself. The casing comprises an auxiliary inlet which is in communication with the discharge chamber of the casing and with the general outlet; the auxiliary inlet is configured for enabling the working fluid to directly enter the casing.

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 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) connectedon one sideto the valve (10) andon the other sideto 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 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) connectedon one sideto the valve (10) andon the other sideto 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 rotary valve internal combustion engine has a piston connected to a crankshaft and reciprocatable in a cylinder, 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 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, wherein the rotary valve is rotatable about an axis parallel to the axis of rotation of the crankshaft, the valve being mounted in a bearing arrangement which restrains the valve from movement in the axial direction but permits movement in the radial direction.