Dihour work state
2016-03-23 by dihour
automatic hand sanitizer dispenser by far infrared automatic sensing work, from the infrared transmitter, receiver, monostable delay switch, solid state relays, and hair dryer and other components, to form a simple self-excited multivibrator, issued out by the infrared emission tube frequency of about 40kHz modulated infrared light. When the staff out into the bottom of the automatic drying hands, emitted infrared rays are reflected back part of the staff, and after receiving phototransistor, converted into electrical signals of the same frequency, and then by special infrared receiver preamplifier integrated circuit amplification, shaping, bandpass comparison, the output low pulse signal, which triggers the monostable circuit into the constitution of the transient, its output high, light, AC solid state relay is turned on, so that power can be sent to a hot hygienic hand dryers. When the hand drying away, losing infrared pulse signal returns high, the monostable reset circuit quickly, due to the delayed effect, and then work up to about 10s hair dryer is automatically restored to stop working