摘要 |
A mixer capable of developing suitable stirring characteristics by forming a sufficient vertical circulation flow over the entire part of the inside of a tank, wherein an opening (4) is formed in a stirring blade (3) under the following conditions: (i) the ratio of the opening area of the opening (4) in the upper half (U) of the stirring blade (3) to the overall area of the upper part (U) of the stirring blade (3) (the opening rate in the upper half (U) of the stirring blade (3)) is 45 to 80%, (ii) the ratio of the opening area of the opening (4) in the lower half (D) of the stirring blade to the overall area of the lower half (D) of the stirring blade (3) (the opening rate in the lower half (D) of the stirring blade (3)) is 18 to 50%, and (iii) the ratio of the opening rate in the lower half (D) of the stirring blade (3) to the opening rate in the upper half (U) of the stirring blade (3) is 31 to 71%. |