Centrifugal multiblade fan

摘要

A centrifugal multiblade fan comprises a plurality of curved blades which are circularly arranged about a common rotation axis at evenly spaced intervals defining a curved air flow passage between every neighboring blades. Each curved blade has concave front and convex rear surfaces which extend longitudinally in parallel with the rotation axis. A lower annular end plate is provided for putting thereon lower ends of the circularly arranged blades. A radially outside part of each curved blade has a radius of curvature which is greater than that of a radially inside part of the blade. A slit extends longitudinally parallel with the rotation axis at a radially inside portion of each blade.