Help Me Design a Simple Automatic Door Operator

[ClayW]

I need some help to design and build a simple, cheap door operator for a screened porch door.

The Problem: I have a screened-in porch with a screen door at the bottom of a short flight of steps. When exiting, the handle is awkwardly low and we often have stuff in our hands. When entering, we're often carrying groceries and/or other stuff into the house. It would be really helpful to have an automatic door operator that is functionally identical to commercial handicap door operators. Of course, a commercial ADA operator is overbuilt and a little expensive for this project.

Possible Solution: If I could figure out the best combination of parts and electronics, I could ideally mount a button-triggered servo/actuator to open the door (and pull the latch). I could also see using a cable system.

So, any ideas? I'm fairly good with fabrication on a limited scale and I can usually figure out electronics.

Thanks in advance for suggestions.

 

[AndyL]

Take the arm assembly from a commercial closer; adapt to a nema 17 stepper motor... pair of limit switches (saves some headache in programing / deciphering number of steps needed to open/ close), an arduino and a 5$ stepper driver chip... oh and probably a 12v wall wart...

My quick off the cuff guess...

 

[JakeKohl]

Remove the latch leaving just the spring closer. Install one of these on the outside?

http://stepnpull.com/

 

[Steevo]

12v linear actuator, maybe a 6" throw, and a 12v dc wall wart, with a GDO-type tap switch on each side and a couple of relays to provide open/close reversing.

 

[bczygan]

Take a small child along. Short, so they're closer to the latch, And they can open the door for you...or you can make them carry the stuff!

Or put one of those cabinet latches that just require bumping to open them. Put it down low so you can kick the door open. Set the door in the jamb so it self closes.

 

[Steevo]

Take a small child along. Short, so they're closer to the latch, And they can open the door for you...or you can make them carry the stuff!

Or put one of those cabinet latches that just require bumping to open them. Put it down low so you can kick the door open. Set the door in the jamb so it self closes.

Keeping small children around to do menial tasks can get expensive. They want to be fed and clothed, and they need a place to sleep, etc. Plus, when you don't need them, they're still around!

Training a dog is easier.

 

[trainer]

Start with an automotive power window regulator and a 12v. power supply

Or one of these....~200 for a unit thats ready to install doesn't sound that expensive.
http://www.ebay.ca/itm/Skylink-Swin...ation_Kits&hash=item58a2b59c56#ht_3627wt_1647

 

[box]

just buy this:

http://www.homedepot.com/p/SkyLink-Swing-Door-Opener-DM-50/203075989

 

[Steevo]

Or one of these:

http://www.power-access.com/Model-2300-door-opener.html

 

[32krazy!]

a rope

 

[nehog]

12v linear actuator, maybe a 6" throw, and a 12v dc wall wart, with a GDO-type tap switch on each side and a couple of relays to provide open/close reversing.

Too slow, at least all the linear actuators I've dealt with.

 

[Steevo]

Too slow, at least all the linear actuators I've dealt with.

That would be a factor of the mount length and placement on the door and wall to create the appropriate mechanical advantage for speed vs. weight.

 

[BD1]

What about a revolving door???

 

[jameswood]

I need some help to design and build a simple, cheap door operator for a screened porch door.

The Problem: I have a screened-in porch with a screen door at the bottom of a short flight of steps. When exiting, the handle is awkwardly low and we often have stuff in our hands. When entering, we're often carrying groceries and/or other stuff into the house. It would be really helpful to have an automatic door operator that is functionally identical to commercial handicap door operators. Of course, a commercial ADA operator is overbuilt and a little expensive for this project.

Possible Solution: If I could figure out the best combination of parts and electronics, I could ideally mount a button-triggered servo/actuator to open the door (and pull the latch). I could also see using a cable system.

So, any ideas? I'm fairly good with fabrication on a limited scale and I can usually figure out electronics.

Thanks in advance for suggestions.

Maybe look at what auto gate openers are avail on ebay then carry it's remote and/or use the sensor of a security light.
Also anything that has gears like broken boat trolling motor parts. Those things were notorious for breaking and many just get rid of them.

 

[24X26]

My father did this exact thing in the 70's.
He used a windshield wiper motor.

 

[animalwheeler]

Or one of these:

http://www.power-access.com/Model-2300-door-opener.html

I'd go for the above or an ADAEZ unit. But realize even though they state some exterior applications, most units like this are meant for interior applications.

But overall, if you buy or make your own:
Make sure you have a good reinforced area in the door header for mounting the arm or operator, whichever you end up mounting to the header. And make sure the hinges on the door will be good enough [no slack/slop] to keep the operator arm swinging in a parallel path.

How are you going to unlatch the door for it to be opened?
No latch? Realize that the operator will need to be able to keep the door shut.

Also: is it windy often? First time the wind really catches that door, it could be bad news as it gets swung full open forcefully. And if the wind is holding the door open, the operator [like above] won't have the oomph to get the door back closed.
But being residential, you may not care about the few times you may have to close it yourself. [Commercial side they REALLY CARE ABOUT having an operator not close on it's own]

 

[Slednut]

You could make one out of a rotisserie (as in BBQ) motor. You could build a cam type mechanism that when you push a button and hold it down it opens the door until you stop pushing the button. Push the button again and release it when the door closes. In other words if you hold the button down the door would constantly open and close. The mechanism would also have a clutch so the door could be opened manually.