WORK APPARATUS HAVING AN AIR-COOLED INTERNAL COMBUSTION ENGINE

摘要

The invention in directed to a work apparatus such as a motor-driven chain saw having a housing and an air-cooled internal combustion engine mounted therein. An exhaust-gas muffler is mounted in proximity to the cylinder of the engine. A flow of cooling air for cooling the cylinder is guided transversely through the housing. In order to obtain an efficient cooling, the muffler has an L-shaped housing and is configured to define a conducting wall for guiding the cooling air flow. One leg of the L-shaped housing is disposed approximately parallel to the flow direction of the cooling air on one side of the cylinder while the other housing leg lies transversely to the flow direction thereby causing the air of the air flow to partially back up. In this way, the side of the cylinder facing away from the flow direction is cooled with the cooling air being effective down to the base of the cooling ribs of the cylinder.