1. Field of the Invention
The present invention relates to an air conditioning apparatus for use in an automobile and more particularly, to an air conditioning apparatus for use in an automobile which is placed in the under surface of a ceiling of the automobile.
2. Description of Related Art
Heretofore, in some conventional air conditioning apparatuses of the type referred to above for use in an automobile, a centrifugal fan has been employed for a ventilator as disclosed in Japanese Laid-open Utility Model Applications Nos. 63-22213 and 63-24011.
In the above-described case where the centrifugal fan has been utilized as a ventilator, however, there have been limits to which the thickness of the air conditioning apparatus can be reduced in a heightwise direction thereof. In other words, the centrifugal fan is of such construction that the air is sucked from an end surface vertical to a rotary shaft thereof and blown out from an outer periphery by the use of the centrifugal force, and consequently it is difficult to make the diameter of the fan small. Accordingly, in the case where the centrifugal fan has its rotary shaft arranged to be horizontal (as disclosed in Japanese Laid-open Utility Model Application No. 63-22213), it becomes necessary to provide sufficient height for the diameter of the fan and also for a fan casing covering the fan.
Generally, the optimum width of the centrifugal fan in the direction of the rotary shaft is equal to the radius of the fan. Therefore, even in the case where the fan has its rotary shaft arranged to be vertical (as disclosed in Japanese Laid-open Utility Model Application No. 63-24011), it is necessary to provide a height relative to the diameter of the fan, and at the same time, it is required to provide a motor in the direction of the rotary shaft for driving the fan.
In the meantime, since the ceiling of the automobile is restricted to a predetermined height by such reasons as the air resistance, the safety of the automobile body, etc., it is a vital problem to reduce the thickness of the air conditioning apparatus in the heightwise direction.