AUTOMATIC HAND DRYER WITH TEMPERATURE DISPLAY

Thesis Abstract

This project deals on the design and construction of automatic hand dryer with temperature display facility which is capable of drying a wet hand placed under its vent goes of automatically. It corporate a temperature sensing and displays unit which displays the temperature of the blown out air. This system is designed in top-down methodology using passive and active components sensors (LM35 & LDR) at the input to sense temperature and hands respectively. The control unit is made up of signal conditioning unit, voltage comparator and frequency generator, and decimal counting unit. The output interface comprises transistor, driver, actuator, Electromagnetic relay and a –digit seven segment Display. The sensor are installed at the front of the blower and this device dries with warm air only. When a hand is placed under the vent to block the line of sight of the LASER Diode and LDR, the blower gets actuated and blows warm air. As the hand is removed, the blower stops automatically along side the temperature display. The principle behind the work of this system is that the hands must be opaque enough to block the line of sight of the opto coupler. This removes the stress, time and dangers associated with push button type. The result being automatic hand dryer with temperature display.