Air dryer and method of dehumidifying air.

摘要

Ambient air passing between an inlet (14) and an outlet (16) through the heat exchanger (12) for drying is cooled by the cold side of a thermoelectric module (28) attached thereto. The opposite hot side of the thermoelectric module (28) is attached to a heat sink (30) which includes a fan (32) which pulls ambient air through the heat sink (30) for dissipating the heat from the thermoelectric module (28). The air is cooled to a temperature below its dew point, causing the moisture in the air to be deposited on the chilled air passage walls (18) of the heat exchanger (12) where it is frozen. When the air passageway (18) of the heat exchanger (12) becomes substantially closed by the ice formation on the walls (18) thereof, the current to the thermoelectric module (28) is reversed, whereby the cold side becomes the hot side and vice versa and, simultaneously, the air exiting is directed from an exit path (22) to an alternate exit path (24). The ice formed on the passageway (18) of the heat exchanger (12) thaws and is removed through the alternate exit path (24). Cooling and heating is then alternately repeated during the operation of the dryer (10). A timer (42) is used to control the alternate reversing.