Patent ID: 8998587
Filing Date: 2015-04-07
Classification: B60H,F04D

Abstract:
1. A blower unit for a vehicle comprising: a fan configured to generate airflow; a motor connected to the fan; a scroll case accommodating the fan; a cooling path connected to the scroll case, the cooling path guiding a part of the airflow from the fan to the motor; a first surface accommodated in the cooling path, the first surface being generally perpendicular to the part of the airflow directed to the motor; and a second surface accommodated in the cooling path, the second surface being substantially parallel to the first surface; wherein the first surface and the second surface at least partially overlap each other in a direction of the airflow directed to the motor, the first and second surfaces defining a first gap therebetween; and a dimension of the first gap is set dependent on a frequency of a noise created by the motor, the dimension of the first gap is determined as follows: f=n*c/(4 L) where “f” is the frequency of the noise, n is an integer “c” is velocity of sound, and “L” is the dimension of the first gap.