Help on fridge door alarm project

[edwardgith]

Hi, i am interested in doing afridge door alrm project.I would like for it to incorporate a mechanism that activates a motor automatically shuts the frdge door when the alarm goes off.In addition i would like the circuit to also have a sensor mechanism that senses when someone is removing or putting something in the fridge.So if the person takes a long time but is still getting something from the fridge the aalrm doesn't go off but waits until the person finishes.If the person forgets to shut the door the circuit waits for the delay time to expire before the alarm goes off which on going off the motor is activated to close the door.Could you assist me to obtain a complete circuit that does all of the above?Also iwould like to know the theory on fridge history,operation and why the fridge door shouldn't be left open for a long time.Thanks in advance

[slingblade]

Yarhaaaarrrrhahahahahahahahahahahahahahahahaha

[dill]

sling your hook slingblade. the guy's new to this site and asked a question that may seem simple to you but how can you learn without asking. I bet he,s got a great impression of the people on this site now.

[chillin out]

Hi Edwardgith,

I wrote out on this page exactly how to do it, but then I thought, you must try to work it out for yourself. All I will say is..

Take a look at a fire door in a public building.
(the kind with the electro-magnetic catch)


why the fridge door shouldn't be left open for a long time.

Now that is a stupid question.

Chillin:) :)

[Brian_UK]

..n addition i would like the circuit to also have a sensor mechanism that senses when someone is removing or putting something in the fridge.Adding on the Chillin's comments; as regards the above action have a look at PIR detectors.

If you want something to time out then investigate delay timers, you should be able to come up with a scheme to resolve your problem.

A simple people sensor attached to an alarm which shouts "Close the door" could also save on the cost of a door closer;)

[Abe]

sling your hook slingblade. the guy's new to this site and asked a question that may seem simple to you but how can you learn without asking. I bet he,s got a great impression of the people on this site now.


To be fair dill...........yes, we can help..........but to a point.

If the guy wants to ask a question, no problem.

But I do not think this place is for novices.....

And posing crazy questions like :why shouldnt the door be left..............:::

What is this????

[chillin out]

OK edwardgith,

Here is more info,
door info
http://www.dortronics.com/
http://www.growinglifestyle.com/us/j4349896
make your own
http://circuitos.tripod.cl/schem/r84.gif
or buy
http://www.schneider.co.uk/products/auto/pcp/timerpcp.htm

combine this with a door switch and there you go.

But you will have to work out how to put all the parts together yourself.
I / we don`t mind helping students but you will not learn anything if people just tell you the answers. You have to be able to work things out for yourself.

good luck

chillin
:) :)