How does the motion sensor in paper towel dispenser work?

Question

is this same technology as those involved in soap dispenser & the rest of them?

Answer 1

my guess is it has a radar or a laser signal constantly sending very weak signals. these signals are so weak that if they hit the floor, they wont be able to reach back to the sensor. When you put your hand in the path of the signal, the signals bounce back and hit the sensor. the sensor then knows to dispence a paper towel. this is just a guess so i am not a 100% sure

Answer 2

The main process is a infra red beam that when it is broken by a hand covering the light the beam signals a motor to turn on and dispense a sheet of paper toweling. Probably the same occurs with any dispensers.

Spartawo...

Answer 3

Never seen one, most have a mechanical cog driven by a gear attached to the roll, when the desired length is reached, the cog stops the roll and the force of your hand pulls the towel off.