Noise reducing blower motor housing means for vacuum cleaner, or the like

摘要

The disclosure concerns a housing for reducing the noise and exhaust air velocity of a bypass type blower motor, particularly a motor used for a tank type vacuum cleaner. The entire housing sits atop the lid of the tank of the vacuum cleaner. The bypass type blower motor has a main, suction generating, centrifugal blower fan and a separate motor cooling fan. Outlet from the main blower fan is into a first expansion chamber above the lid. A spiral pathway baffle in the first expansion chamber defines a gradually increasing cross-section plenum which communicates from the fan to the outlet from the first expansion chamber. There is a tubular outlet from the first expansion chamber which is surrounded by a sound baffling cuff of foamed plastic material. A cooling air inlet to the motor cooling fan and a separate cooling air outlet from the casing for the motor cooling fan are provided. A second expansion chamber communicates with the cooling air outlet from the casing for receiving the exhausted motor cooling air. The second expansion chamber separates the inlet to the motor cooling fan from the outlet from the motor casing for the cooling air. The outlet for the exhausted cooling air from the second expansion chamber faces in the same direction as the inlet to the motor cooling fan. A cover passes over the cooling air inlet and outlet. A baffle between the second expansion chamber and the cover separates the air flows to the cooling air inlet and outlet.