Air Blowing Unit For Vehicle

Abstract

Provided is an air blowing unit for a vehicle which, even when a backflow prevention means which prevents the flow of air which flows back through a gap formed between a bottom surface of an impeller and an upper surface of a motor flange is adopted, optimally maintains a size of the gap thus suppressing noises and the collection of moisture and, can suitably boost a pressure of air in a scroll case portion.With respect to a case of an air blowing unit, a projecting portion is formed in a projecting manner on an inner side of a second wall portion on a side opposite to a first wall portion where an air suction port is formed as an air backflow prevention means. The projecting portion is positioned outside an impeller in the radial direction with a predetermined gap between a radial outer end of the impeller and the projecting portion.

Description

TECHNICAL FIELD[0001]The present invention relates to an air blowing unit used for a vehicle such as a vehicle air conditioner or a cooling device of heat source for a vehicle.BACKGROUND ART[0002]An air blowing unit used for a vehicle such as a vehicle air conditioner or a cooling device of heat source for a vehicle is basically constituted of, as disclosed in patent literature 1 and patent literature 2, for example, an impeller which generates an air flow by rotation, a motor which rotatably drives the impeller, a case (particularly, a scroll case portion which houses the impeller and is mainly constituted of a peripheral wall formed around a radial side of the impeller), and a motor flange on which the motor is mounted. As a function of such an air blowing unit, air is sucked into the inside of the scroll case portion through an air suction port formed in the scroll case portion by rotatably driving the impeller by the motor, a pressure of the air is boosted in the scroll case por...

AI Technical Summary

Benefits of technology

The invention described in this patent prevents air from flowing back into an air blowing passage and prevents the formation of a vortex, which can lock the rotation of an impeller. The air backflow prevention means achieves this by forming an inclined surface that guides air flow and prevents air from flowing into the gap space between the impeller and a second wall portion. It also ensures that air flow is efficient and prevents wind noises from being generated. Additionally, it increases the cross-sectional area of the air blowing passage and decreases the air flow resistance, resulting in improved air blowing efficiency.

Problems solved by technology

However, when a predetermined size is not ensured with respect to the gap space formed between the bottom surface of the impeller and the upper surface of the motor flange or the gap space formed between the bottom surface of the impeller and the upper surface of the motor flange has a complicated shape, there is a possibility that moisture will collect in the gap space.

In the case where the moisture is frozen, even when the motor is driven, the impeller is locked so that the impeller is not rotated, and there is also a possibility that the motor will catch fire depending on a situation.

On the other hand, in the centrifugal blower disclosed in patent literature 1, the gap space formed between the bottom surface of the impeller and the upper surface of the motor flange has the narrow and complicated structure due to the cylindrical rib formed on the motor flange side and the cylindrical rib formed on the impeller side and hence, risk such as a collision between the impeller and the motor flange due to vibrations or the locking of the rotation of the impeller is increased.

Images