Patent ID: 8579586

Claim:
A bell mouth for a scroll case, which is provided on a top plate of the scroll case to form an air inlet in order to allow air flow into the scroll case by a centrifugal blower installed inside the scroll case, wherein: a volume of two parts of the bell mouth in respect to a rotation shaft of the centrifugal blower is different from each other; the scroll case includes a scroll part having an air flow path on an outside of the centrifugal blower, an outflow part connected to the scroll part and extended toward an outlet of the scroll part, and a cut off part that is a beginning part of the scroll part, where the air flow path begins to be enlarged and when an angle of a line, parallel to an extending direction of the outflow part, among lines extending from a center of the centrifugal blower to an outline of the scroll case is set as a reference angle, a radius of the bell mouth varies as a position determining angle of an azimuthal plane increases from the reference angle to the position determining angle of the cut off part.