Patent ID: 7461617

Claim:
An engine-driven work machine in which an engine/work machine unit ( 5 ) is formed by joining an engine ( 2 ) and a work machine ( 4 ) driven by a crankshaft ( 3 ) of the engine ( 2 ), the engine/work machine unit ( 5 ) and an exhaust muffler ( 23 ) joined to the engine ( 2 ) are housed in a box ( 30 ), the box ( 30 ) is provided with a cooling air passage ( 44 ) that reaches an air outlet ( 40 ) opening on an outer face of the box ( 30 ) from an air inlet ( 39 ) opening on the outer face of the box ( 30 ) while passing sequentially via the area around the engine/work machine unit ( 5 ) and the area around the exhaust muffler ( 23 ), and a cooling fan ( 15 ) is provided for generating a flow of air in the cooling air passage ( 44 ) when the engine ( 2 ) is running, characterized in that the box ( 30 ) is provided with blocking means ( 51 ) for blocking the cooling air passage ( 44 ) between the engine ( 2 ) and the exhaust muffler ( 23 ) when running of the engine ( 2 ) is stopped.