Piston engine combined with a Joule cycle

The turbomachine (10,11) uses the motor vehicle internal combustion engine (18) exhaust gas heat in a heat exchanger (7) to provide a heat source. The turbomachine drives an air compressor (9) which supercharges the internal combustion engine. The power front the turbomachine is transferred pneumatically to the engine, in that the work effected by the compressed air is exerted on the engine piston.