Vacuum cleaner has plenum chamber in motor exhaust duct to reduce operating noise

摘要

Vacuum cleaner has a casing (2) containing a blower motor. Casing has an inlet (12) and an outlet (60) for the air flow. Air plenum chamber (50) is positioned in flow path between a motor outlet duct and casing outlet opening to return aspirated air. Inlet section for chamber is at least double, due to a bidirectional enlargement of the section, than that of flow duct (46) leading to the chamber.