The Science of Sensor Faucets Genevieve Toh (7) Class 113

Sensor Faucets Use sensor to detect hands  automatically dispense water for a preset amount of time.

Mechanism Solenoid valve Electrical energy  Kinetic energy Starts or stops water flow Set flow duration, water temperature Infrared sensor Detects presence of hands Sends electronic sensor to solenoid valve Power source Mains or batteries Body shell Varied designs and styles

Senor eye beams out an infrared signal range about 20-26cm wide. When place hand inside sensor range, sensor detects it and send electronic signal via wire to solenoid.

Solenoid converts EE to KE and opens valve. Water is channelled through flexible hose out of faucet. Flow duration pre-set.

Sensor soap dispenser & toilet flush

References Prader J. (2011). How do hands-free faucets work? Retrieved April 12, 2012 from handsfree-faucets-work.html handsfree-faucets-work.html Autotaps Limited. (2006). Benefits of electronic sensor water taps. Retrieved April 12, 2012 from taps.html taps.html Coxworth B. (2011). Hands-free faucets not necessarily better, say scientists. Retrieved April 12, 2012 from free-faucets-not-necessarily-better/18301/ free-faucets-not-necessarily-better/18301/