Unconventional Switch: Fridge Door Switch--David Trefry and Tyrell Whitby

  Fridge Door Switch

 Hello, our unconventional switch is a Fridge Door Switch. Its purpose is to remind you to close the fridge door after you open it. This switch is part of a breadboard powering a 2-volt red LED. We took two lengthy breadboard wires--which complete its circuit when they touch--affixed aluminum foil to their ends with conductive tape and then taped them to the side of a fridge so that the foil sticks out beyond the fridge door’s lip.

These conductors don’t ordinarily touch as they are taped separately. However, when the fridge door is closed, its stainless-steel exterior touches both pieces of foil, bridging the gap to complete the circuit.

The inspiration for this switch came from personal experience with a father that never remembered to close the fridge door. It would appear shut but still had a small gap in the door. Only when the fridge’s alarm, set off by a high temperature, went off would he notice his error. By this point however, damage had already been done to the fridge’s contents.

This switch is designed so that only when the door is properly closed, the breadboard’s LED turns on to confirm that fact. 

Schematic

  

 

Video Demonstration