Humidifier

Claim 1

An air humidifying apparatus comprising: means defining a water reservoir for retaining a predetermined level of water therein; water vaporizing means operatively associated with said reservoir for gradually and controllably vaporizing the water retained therein; detecting means for detecting said water level in said reservoir and for responsively generating a high level signal corresponding to a water level in said reservoir above said predetermined level and for generating a low level signal corresponding to a water level in said reservoir below said predetermined level; and indicating means operatively connected to said detecting means for visually indicating whether the water level in said reservoir is above or below said predetermined level in response to said high and low level signals, respectively, said indicating means including first and second light-emitting diodes and means to selectively energize said first or second light-emitting diodes in response to said high or low level signals, respectively, to selectively cause light to be emitted thereby corresponding to said high and low water levels to provide visual indication thereof; wherein each said first and second light-emitting diodes is connected in series to a transistor, the base current of said transistor being controlled by said detecting means.