Chicken Coop Door Opener

Discussion in 'The Projects Forum' started by flumes, Jun 6, 2016.

  1. flumes

    Thread Starter New Member

    Jun 6, 2016
    1
    0
    I have a 12 volt linear actuator that I am hoping to use to open/close a door in my chicken coop at certain times in the day.

    The linear actuator has built in limits and operates at less than 5 amps, but I would rather use seperate limit switches to control the amount of stroke the actuator has.

    I am thinking of using a 12V power supply connected to a digital timer to send power ( + - ) in the morning to open the door. I would then use a different timer to send power (- + ) in the evening to close the door.

    Any ideas how I can make this work, (using relays and micro switches)?

    Any help would be appreciated.

    I will by beer :)
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,552
    2,374
    There are several posts here on Chicken door openers, could you adapt one of those?
    Max.
     
  3. crutschow

    Expert

    Mar 14, 2008
    13,019
    3,235
    You could use a single sprinkler type timer (such as this) since they have more than one output.
    Note that the output of these timers is typically 24Vac so the relay coils also needs to be 24Vac (example).
    Here's a conceptual connection diagram for the relays and limit switches.

    The timer output takes the place of the switch, with the relay coil returns going to the timer output instead of the motor power supply.

    Edit: Note that relay contact protection from the inductive motor kick is not shown and should be added.
    For that you should connect two diodes (1A or greater such as 1N400x) to each motor connection (4 diodes total), one V+ to motor (anode) and the other V- to motor (cathode).
     
    Last edited: Jun 6, 2016
  4. KeepItSimpleStupid

    Well-Known Member

    Mar 4, 2014
    1,146
    204
    Find a timer. Decide on a power supply for the timer.

    Two SPDT Bosch Automotive style relays hooked up the right way (see power door lock wiring) will give you an OPEN//CLOSE relay.
    The wiring method causes the motors to stop fast.
    The limit switches basically would interrupt the respective OPEN/CLOSE coil.
    For DC, you should use reverse biased diodes on the relay coils.

    Now, you can turn these two OPEN/CLOSE signals into an ON=OPEN, OFF=CLOSED from your timer.

    Would chickens prefer an autonomic timer? A timer that can turn on/off based a time before after sunset/sunrise?
     
  5. AlbertHall

    Well-Known Member

    Jun 4, 2014
    1,951
    387
    How do you stop the door squishing a chicken?
     
  6. Alec_t

    AAC Fanatic!

    Sep 17, 2013
    5,801
    1,105
    If you use external limit switches you will have to teach your chickens not to mess all over them ;).
     
  7. crutschow

    Expert

    Mar 14, 2008
    13,019
    3,235
    Two things make that unlikely:
    The door probably moves slowly enough that the chicken would naturally have plenty of time to get out of the way.
    The door is normally closed after sundown to make sure they are all already back in the coop. You don't want to close the door with any still outside (where they can become a tasty meal for night-time predators).
     
  8. GopherT

    AAC Fanatic!

    Nov 23, 2012
    6,059
    3,821
    Why would you want to stop the door? No wasted efforts chasing down a chicken on the days one gets tenderized in the door.
     
  9. GopherT

    AAC Fanatic!

    Nov 23, 2012
    6,059
    3,821
    I would just use a current sense resistor and assume it is closed one enough current is drawn in each direction. I would be using a motor and toothed belt instead of a linear actuator.
     
  10. splud

    New Member

    Jun 30, 2013
    6
    0
    FTR, limit switches can be placed in the sides of the door frame on the side and ABOVE the opening and trigger on detents in edges of the door. This keeps them up and away from debris. The head of an old toothbrush or part of a paintbrush can be used as a brush near where the edge of the door runs into the track, knocking away any debris carried up by the door, so that is stays away from the switch.

    I've constructed a couple of auto coop door openers, and used a small geared DC motor, operating it more as a regulator, with the door (a piece of galvanized sheetmetal with the bottom edge folded over so it isn't sharp) counterweighted. In such an arrangement, there is not much apparent weight to the door. Think of old-school double-hung windows.
     
  11. AlbertHall

    Well-Known Member

    Jun 4, 2014
    1,951
    387
    Presumably a magnet and a couple of reed switches would avoid the problem?
     
  12. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,552
    2,374
    Or proximity switches and a ferrous metal flag.
    Seems the OP has left the building?
    Max.
     
Loading...