Fan for vacuum cleaner - has asymmetrical inlet opening to enable handling long threads without becoming blocked

摘要

A fan housing (2) contains an impeller (4) which has centrifugal blades (5). An inlet channel (8) in the casing leads to a suction inlet (6) in the eye of the impeller. The channel comes from the cleansing pickup (9) of the vacuum cleaner. The inlet (6) into the impeller is pear shaped with a lobe (7) projecting asymmetrically on one side of the shaft centreline (3). This projection is in the delivery direction of the blades. This arrangement of the inlet prevents long threads picked up by the cleaner from taking up a symmetrical position on the dia. of the impeller from which the air flow cannot dislodge them. It therefore enables the cleaner to remove long threads and prevents its becoming blocked by them.