| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a centrifugal blower for vehicle air conditioning equipped with a scroll casing which has excellent fan efficiency and exhibits noise reduction effect. <P>SOLUTION: A centrifugal blower includes: a multi-blade fan whose fan exit angle falls within an angular range of 20°-75°; and a spiral scroll chamber which is a scroll chamber surrounded, at the periphery of the multi-blade fan, by a spiral casing whose spiral spread angle falls within an angular range of 2°-6° taking a winding start portion as a starting point and which has a top and bottom faces of the scroll chamber shifted axially downward between the winding start and end portions, wherein when a distance from a center surface (U) at one-half height of an axial height H of the impeller to a center position (V) between the top face and bottom face of the scroll chamber in the winding end portion is taken as an offset amount (L), the offset amount (L) falls into a range of 0.1-0.18H with respect to the axial height H of the impeller. <P>COPYRIGHT: (C)2012,JPO&INPIT |
