Electric motor driven blower assembly with integral motor cooling duct

DETAILED DESCRIPTION The subject invention provides an alternative structure for providing an integral motor cooling air passage, with better sealing and higher tolerance at the joint.
In the preferred embodiment disclosed, a cylindrical air supply tube molded integrally to the outside of the fan scroll housing extends from a lower end exposed to the air stream to an upper end above the back of the scroll fan housing, generally parallel to the blower axis.
Fan pressurized air can enter the inlet of the tube and exit the upper end, but needs to turn 90 degrees and move radially inwardly to reach the motor.
A motor holding cover adapted to be bolted to the back of the scroll housing has a trough shaped duct integrally molded therein, which extends radially to an outer end beyond the basic perimeter of the motor cover.
The cooling tube is located so that its upper end projects into the end of the open trough when the motor cover is bolted to the scroll housing.
A separate, elastomer vibration absorbing gasket surrounds the perimeter of the motor cover, to be captured between the cover perimeter and the scroll housing when attached.
A projection on the gasket overlies the end of the open trough, with a central window through which the upper end of the air supply tube tightly and sealingly inserts when the motor cover is bolted in place.
The extra gasket material provides the transitional corner from the scroll housing cooling tube into the motor cover, and provides a tight, high tolerance seal.
No extra parts, and no extra assembly steps are required.