Cooling channel for automotive HVAC blower assembly

A centrifugal blower comprising:

• a centrifugal fan including a hub adapted for rotation about a central axis, and a plurality of blades coupled for rotation with the hub;
• a motor having a drive end, an opposite end and an axial length, the motor including a drive shaft drivingly connected to the hub of the centrifugal fan, the drive shaft extending from the drive end of the motor, and the motor having therethrough an airflow path for cooling the motor, the airflow path having an inlet near the opposite end of the motor and the airflow path having an outlet near the drive end of the motor;
• and
• housing structure including
• a blower housing portion at least partially defining a space in which the fan is substantially enclosed, the space having an inlet and an outlet;
• a motor housing portion supporting the motor;
• a flange portion at least partially supporting the motor housing portion on the blower housing portion, the flange portion and the hub defining therebetween an axial gap, and the flange portion including a surface that extends generally parallel to the axis;
• a separate cover which extends in part over the opposite end of the motor;
• the motor housing portion being formed in part by structure integral with the flange portion and in part by the cover;
• a cooling air path defined by the flange portion and by the cover, the cooling air path having
• an inlet that is located in the surface of the flange portion and that communicates with the space,
• an outlet communicating with the inlet of the motor airflow path,
• an upstream portion that extends radially inwardly and axially in the direction from the opposite end of the motor toward the drive end of the motor, the upstream portion of the cooling air path being defined in part by a ramped surface on the cover, the upstream portion including a wall that extends toward and terminates at a point spaced from the ramped surface, the upstream portion including a dam that extends upwardly from the ramped surface, the dam and the wall resisting downstream water flow in the cooling air path, and the upstream portion having a low point adjacent the inlet and having a high point adjacent the downstream end of the upstream portion, the high point being defined by the dam, and wherein a line from the low point to the high point defines an angle of greater than approximately ten degrees with respect to horizontal, and
• a downstream portion that extends axially in the direction from the drive end of the motor toward the opposite end of the motor, the downstream portion of the cooling air path extending substantially the entire length of motor, and
• a second cooling air path communicating between the outlet of the motor airflow path and the axial gap.

A method of mounting a centrifugal blower in a vehicle, the method comprising:

• providing a centrifugal blower having
• a centrifugal fan including a hub adapted for rotation about a central axis, and a plurality of blades coupled for rotation with the hub;
• a motor having a drive end and an opposite end, the motor including a drive shaft drivingly connected to the hub of the centrifugal fan, the drive shaft extending from the drive end of the motor, and the motor having therethrough an airflow path for cooling the motor, the airflow path having an inlet near the opposite end of the motor;
• and
• housing structure including
• a blower housing portion at least partially defining a space in which the fan is substantially enclosed, the space having an inlet and an outlet;
• a motor housing portion supporting the motor;
• a flange portion at least partially supporting the motor housing portion on the blower housing portion;
• and
• a cooling air path having an inlet communicating with the space and an outlet communicating with the inlet of the motor airflow path, the cooling air path having an upstream portion that extends axially in the direction from the opposite end of the motor toward the drive end of the motor, and the cooling air path having a downstream portion that extends axially in the direction from the drive end of the motor toward the opposite end of the motor;
• and
• mounting the blower in a vehicle such that the central axis extends non-vertically and non-horizontally, and such that the inlet of the cooling air path is substantially directly below the axis.