Blower fan

A blower fan comprising:

• a shaft;
• an impeller arranged to rotate about a rotation axis together with the shaft;
• and
• a motor arranged to rotate the impeller;
• wherein
• the impeller includes a substantially cylindrical impeller cup fixed to the shaft, and a plurality of blades arranged on an outer circumferential surface of the impeller cup;
• the motor is arranged radially inward of the impeller cup, and includes a stator, a substantially cylindrical stator support portion, and a base portion;
• the stator of the motor is fixed to an inner circumferential surface of the stator support portion;
• the base portion is arranged to extend radially outward from an outer circumferential surface of the stator support portion;
• an opening-side end portion of the impeller cup is arranged opposite to an axially upper end portion of the base portion;
• and
• the axially upper end portion of the base portion includes an expanded portion defined at least in a portion thereof which is opposed to the opening-side end portion of the impeller cup, the expanded portion being located a greater distance from the opening-side end portion of the impeller cup than a distance between the opening-side end portion and a remaining portion of the axially upper end portion of the base portion.

A blower fan comprising:

• a shaft;
• an impeller arranged to rotate about a rotation axis together with the shaft;
• and
• a motor arranged to rotate the impeller;
• wherein
• the impeller includes a substantially cylindrical impeller cup fixed to the shaft, and a plurality of blades arranged on an outer circumferential surface of the impeller cup;
• the motor is arranged radially inward of the impeller cup, and includes a stator, a substantially cylindrical stator support portion, a base portion, and a circumferential wall;
• the stator of the motor is fixed to an outer circumferential surface of the stator support portion;
• the base portion is arranged to extend radially outward from the outer circumferential surface of the stator support portion, and the circumferential wall is arranged to extend axially upward from a radially outer end portion of the base portion;
• an opening-side end portion of the impeller cup is arranged opposite to an axial end portion of the circumferential wall;
• and
• the axial end portion of the circumferential wall includes an expanded portion defined at least in a portion thereof which is opposed to the opening-side end portion of the impeller cup, the expanded portion being located a greater distance from the opening-side end portion of the impeller cup than a distance between the opening-side end portion and a remaining portion of the axial end portion of the circumferential wall.