Abstract: A motor cooling fan housing for a by-pass vacuum motor is presented. The fan housing includes a top plate connected to a cylindrical side portion. The top plate is characterized by a plurality of uniformly spaced tear-drop shaped slots therein. The slots provide for the entry of cooling air to the motor maintained therein. The slots are elongated and have a major axis which is non-collinear with the center point of the top plate of the housing.

Abstract: A quiet by-pass vacuum motor wherein a ring-like cavity is defined between inner and outer walls of the housing for a working air fan. Separating members divide the cavity into passageways which communicate with openings in the housing. A plate having a plurality of vanes thereon is received upon the separating members, the plate extending from the outer wall to a position short of the inner wall. A baffle plate is then received upon the vanes. Working air is exhausted over the baffle plate, between the vanes, over the plate and between the separating members and through the openings. The exhaust path greatly reduces the noise level of the vacuum motor.