US Patent 7356943 Automatic hair dryer

An automatic Hair dryer including a hand held body, a comb attached to the body, a 120/240 V.A.C. heating element and a fan adapted to move a mass of air across the heating element and through or across the comb and into an individual's hair. A moisture sensor is disposed between the teeth of the comb and is powered by a 12 volt D.C. power supply such as a step-down transformer. When the sensor senses moisture, the comb is passed through an individual's hair and the 120 -volt A.C. current is connected to the heating element. Then, when the moisture content of the hair is relatively low, the sensor activates a switch that turns off the power to the heating element while the power to the fan is maintained until a master switch is turned off.