Patent ID: 6295953
Filing Date: 2001-10-02
Classification: F01P,F02B,F02M,Y10S

Abstract:
A portable power working machine, comprisinga small air-cooled internal combustion engine received in a main housing,a cooling fan which is adapted to be driven by the internal combustion engine and is disposed on one side of the main housing,a carburetor chamber housing therein an air cleaner for the internal combustion engine and a carburetor,a dust-separating air duct interposed between a region close to the cooling fan and the carburetor chamber, the dust-separating air duct including a partitioning wall member extending along the length of the air duct and forming in the air duct a dust-separating passageway and a dust-exhaust passageway substantially co-extensive with the dust-separating passageway, the dust-separating passageway having an air inlet port for receiving air from the cooling fan and which is open in a direction opposite to that facing the impeller of the cooling fan and an air feeding port for delivering the air to the carburetor chamber formed below a top wall disposed close to the air cleaner of the carburetor chamber, and the dust-exhaust passageway being communicated with the dust-separating passageway by an opening in the partitioning wall member which is formed close to the top wall and has an outlet port opening close to the impeller, thereby allowing the dust collected at an inner corner portion of the top wall to be carried by an air flow and then to be discharged from the outlet port by suction of the cooling fan.