automatic door, strictly mechanical coop design

[toddreed]

Hey there,

Sounds like a wonky question, i'm sure, but I was wondering if anyone has attempted or seen an automatic opening and closing coop which uses strictly mechanics, i.e., no motors, timers or any electronics? I am playing around with some rough drawings of this idea and I just thought i'd ask if it has been done before in any form or fashion?

The basic operation idea for mine is a draw-bridge-style, i.e. bottom-hinged, door, that, when all the hens come off the roost in the morning and hang out on the coop floor, their weight slightly lowers a hinged floor which releases the door-latch to let them out in the morning, and then when and only when the very last hen hops up to the roost in the evening, their total weight mechanically raises the door to close it. The system would be calibrated with adding or subtracting counter-weights to match the total weight of the birds in the coop. Sounds pretty pipe-dreamy, but I think it can be done. I guess the only catch is it would need to be re-calibrated every so often as the hens gain or loose weight.

Thoughts / criticism welcome,
-todd

 

[Bear Foot Farm]

To just get right to the point, there is NO way you could ever get it balanced correctly to make it work reliably, if at all, because there are too many variables

 

[lokua]

I think the good old fashioned wind up alarm clock would work better. Take a wind up clock, put a small pulley on the winding knob for the alarm and use it to winch up a string attached to the door. Set the alarm for whenever you want the door opened in the morning. Obviously you need a light weight door...think thin sheet metal. Of course you need to close it up manually and rewind the clock but you can sleep in at least.