Why do I keep trying to reply when I should be getting dressed for work
Guys: the circuit I have in mind is basically two 555 one-shots -- one for each direction. They are timed for a bit longer than the door should take to move. Each one-shot starts running when power is applied and shuts off either when the limit switch is hit, or when it times out. By using a 555, you have enough drive for a relay built in without needing extra parts. FOr a low-speed circuit like this one, relays are cheaper than building H-bridges out of transistors or even buying an H-bridge off the shelf.
I don't have a schematic drawn up since my big project right now is a light sensor to get the coop light on when the sun goes down. That will also be the initial control for the door. Once that's all working, I'll build a real timer so I can tell it exactly when to open/close.

Guys: the circuit I have in mind is basically two 555 one-shots -- one for each direction. They are timed for a bit longer than the door should take to move. Each one-shot starts running when power is applied and shuts off either when the limit switch is hit, or when it times out. By using a 555, you have enough drive for a relay built in without needing extra parts. FOr a low-speed circuit like this one, relays are cheaper than building H-bridges out of transistors or even buying an H-bridge off the shelf.
I don't have a schematic drawn up since my big project right now is a light sensor to get the coop light on when the sun goes down. That will also be the initial control for the door. Once that's all working, I'll build a real timer so I can tell it exactly when to open/close.