Abstract: To efficiently recover excess energy available in a turbo supercharger (4) operated by exhaust gases from an internal combustion engine (ICE) (1), when the loading of the ICE exceeds about half of rated load, a hydraulic pump--motor unit (10) is coupled to the shaft of the turbo supercharger. The hydraulic unit (10) provides output over a hydraulic line (14) through a selectively operated valve (30) to either a hydraulic motor (15), which is coupled to an energy utilization system, for example a generator (17), or to return hydraulic fluid to a sump or suply (11). A controller (21) controls operation of the valve. If the exhaust gases are insufficient to provide excess energy for the hydraulic motor (15), the valve is controlled to return hydraulic fluid form said motor--pump unit so that, in effect, said unit (10) is idling.

Abstract: Auxiliary compressed air is supplied to an inlet manifold (3) of an internal combustion engine (1) by an auxiliary compressor (8), driven from the main shaft of the ICE. A controlled clutch (17) is interposed between the engine (1) and the auxiliary compressor, the clutch being controlled by a memory and controller (18) receiving inlet manifold pressure signals (P) and fuel quantity signals (F) and providing output control signals to the controlled clutch (17) based on stored functions or tables within the memory and controller to provide for desired and optimum operation of the engine with appropriate charge air in view of injected fuel quantity. The compressed air derived from the auxiliary compressor (8) is injected into the main compressor to impinge on the vanes or blades (15) of the main compressor (6).

Abstract: Connecting exhaust ducts of gradually widening cross section lead from the exhaust ports of a particular cylinder to a common manifold, being continued inside the manifold for a length greater than half of the diameter of the manifold and leaving an outflow cross section between the end of the connecting duct and the facing wall of the manifold equal to or slightly greater than the exit cross section of the connecting duct. Between junctions with the connecting ducts the manifold has sections of constricted cross section, providing baffling between the connecting ducts. The arrangement enables the kinetic energy of the outflow of exhaust gas to be more effectively utilized for sucking in the scavenging air.