Abstract: A tappet carrier for a barrel type internal combustion engine includes a body having a central bore that is coaxial with a camshaft of a barrel engine. The tappet carrier further comprises a plurality of radially extending bores that are continuous with the central bore so as to allow mechanical communication between the tappets and the camshaft.

Abstract: A shaft assembly for a barrel internal combustion engine having valves controlling the intake and exhaust of gases during operation of the engine. The shaft assembly includes a drive shaft and a cam shaft. The drive shaft extends longitudinally between opposite first and second ends along a rotational axis. The cam shaft has cam lobes for actuating the valves of the engine. The cam shaft is coupled in a spline arrangement with an end of the drive shaft for rotation therewith about the rotational axis. The cam shaft is substantially coaxial with the drive shaft.

Abstract: In a double-ended barrel engine, a compression cylinder and a combustion cylinder share a common axis, with a combustion piston and a compression piston being interconnected by a connecting rod. The compression end of the engine includes a valve plate assembly with a generally flat valve plate with intake and exhaust passages defined therethrough. An intake flapper valve is disposed on the inner surface of the valve plate and selectively covers the intake passage. An exhaust flapper valve is disposed on the outer surface of the valve plate and selectively covers the exhaust passage. Additional cylinders and pistons may be provided. A compression plenum may be provided in fluid communication with the exhaust passages from one or more compression cylinders, and be in fluid communication with the intake system for the combustion end of the engine. A wastegate may be provided for venting the compression plenum.