Blower / vac tools with improved fan blade noise

Abstract

Blower/vacuum tools having reduced fan blade noise are provided. A blower/vacuum tool includes a main body extending between a first end and a second end defining an airflow conduit therethrough; and a fan assembly. The fan assembly includes an axial fan having a number of fan blades (nb), and a motor rotatably connected to the fan. In some embodiments, when ng is in a range from 17-45, the axial fan has a Blade Solidity in a range from 0.0464nb≤Blade Solidity≤0.089nb calculated by the equation Blade Solidity=c/s where c is the length of the chord line of the fan blades, s=2πrm/nb, and rm is the mean radius of the fan blades. In some embodiments, when the motor operates at a speed of between 21000-38000 rotations per minute (RPM), blade pass frequency (BPF) of the fan assembly as defined by the equation B ⁢ P ⁢ F = ( R ⁢ P ⁢ M 6 ⁢ 0 ) * ( # ⁢ of ⁢ blades ) is greater than 6 KHz.

Dependencies are inferred from the claim text.