IMPELLER OF SIROCCO FAN AND METAL MOLD FOR FORMING THE SAME

摘要

PROBLEM TO BE SOLVED: To increase a blast amount or the like at the blasting by specifying a relationship between a visible line of a section of one end of a blade plate and a visible line of a section of the other end. SOLUTION: A point of a blade plate 1 and a visible line of a section of a basic end are formed by the curves within a specific range on the basis of a curve of continuous circular arc. That is, when coordinates of an x-y line coordinate is taken on a circular arc obtained by connecting a point (a)-a point (d), or a point (a')-a point (d'), a range of±5% of a numerical value of the coordinates is determined, so that the visible lines of the sections of the point end and the basic end of the blade plate 1 are formed by the curves within this range. The installation angle of each blade plate 1 is determined within±2 deg. on the basis of an angleθ1 between a line connecting an origin (o) and a point (c) and a y-axis, and an angleθ2 between a line connecting the origin (o) and a point (c) and the y-axis.