| 摘要 |
A filtered air moving device including a housing defining an air inlet, an air outlet, and an air flow path therebetween; a blower disposed in the housing and arranged to move air in the flow path from the inlet to the outlet; a multiple speed electrical motor rotatably coupled to the blower; and an air filter disposed within the housing in the air flow path. Also included is a control circuit for connecting the motor to a voltage source and including an electrical switch operable between a first condition providing rotation of the blower at a given speed and a second condition providing rotation of the blower at a predetermined speed greater than the given speed; a tubulation providing communication between a location in the air flow path downstream of the filter and a position remote therefrom; an indicator responsive to the rate of air flow through the tubulation, and a selector for varying the level of resistance to air flow provided by the tubulation.
|
