The first condo I ever owned was arranged like a chimney – every room was on its own floor. (Well, they were staggered, so each room was ½ a flight of stairs away from the other.)
My bedroom was on the very top floor, and in the summertime it got really hot up there because, you know, heat rises. So all the heat from the condo rose up and accumulated in my room. But it was cool outside. So I kept the window open to be cool enough to get to sleep, but by 4:00 AM it got so cold that it woke me up. I’d get up, close the window, and try to go back to sleep.
This Automatic Window Closer solved that problem. I took a motor designed to slowly spin a mirror ball in a dance hall and a thermostat and hooked them together. What you can’t see is a fishing line attached between the motor and the horizontally-travelling window.
When it got cold enough, the thermostat would turn on, which turned on the motor, which very slowly pulled the window closed by the fishing wire. When the window was 98% closed, a magnet on the window frame came close to a reed switch (also not shown), and the motor turned off.
This was the only invention of mine that ever worked on the first try.
When I sold the condo, I kept this invention on the wall for the future owners. Don’t know if they appreciated it or not.