| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a tangential fan impeller which effectively reduces discrete frequency noise, and to provide an air conditioner using this tangential fan impeller. <P>SOLUTION: (1) Respective blades 31 are collected into even number groups having mutually the equal number of sheets, and adopt the constitution having a pitch difference angle ε becoming β=α+ε and γ=α-ε when a virtual average pitch angle is set to α, a pitch angle between the respective blades in adjacent one group among the respective groups is set to β, and a pitch angle between the respective blades in the other group is set to γ. (2) Respective blocks are dislocated by an angle γ in the shaft direction, and are adjacently joined, and are dislocated by an angle δ for minimizing synthetic sound pressure of an NZr component wave of the respective blocks to form an arrangement fan. <P>COPYRIGHT: (C)2003,JPO |
