Patent ID: 8591183

Claim:
A blower assembly comprising: a motor having an output shaft that is rotatable in a rotation direction around a rotation axis, the rotation axis defining mutually perpendicular axial and radial directions relative to the blower assembly; an impeller mounted on the output shaft for rotation with the output shaft, the impeller having a plurality of blades that surround an interior of the impeller; and, a blower housing with an air inlet opening and an air outlet opening, the blower housing having an end wall with a shaft opening on an axially opposite side of the impeller from the air inlet opening, the blower housing having a side wall that extends axially from the end wall and defines an interior of the blower housing, the motor being mounted on the end wall with the output shaft extending through the shaft opening to the impeller in the blower housing interior and there being no other obstructions extending from the blower housing into the interior of the blower housing and into the interior of the impeller that would obstruct a free flow of air through the air inlet opening and into the interior of the blower housing and into the interior of the impeller and from the interior of the impeller through the plurality of fan blades surrounding the interior of the impeller to the blower housing side wall, the side wall having a first end that defines a cutoff adjacent the air outlet opening and a point on the side wall that is spaced in the rotation direction from the cutoff by an arc of at least 45°, the side wall being a radial distance from the rotation axis that is substantially constant as the side wall extends from the cutoff to the point on the side wall and increases at a rate as the side wall extends in the rotation direction away from the point on the side wall toward the air outlet opening, the rate defining an increasing expansion angle of the side wall, and the side wall being a continuous curve as the side wall extends in the rotation direction from the cutoff through the point on the side wall and toward the air outlet opening.