help w/ button for opening/closing a lid

[NJFAIL]

I'm altering the fan ducts inside my car, so everything must be 12v.

I'd like to have a button that opens and closes a lid on a vent.
When the button is pushed, the vent opens, when the button is bushed again, the vent closes.

I'm thinking I could have a dc motor attached to the vent lid. Does anyone know a website that sells 12v motors w/ reverse? and what kind of a button am I looking for?
I'll have 12 buttons/vent lids, a button for each vent lid.
attached is a picture of what I'm talking about with the vent.

Thanks for the help! feel free to ask about something if I wasn't clear.

 

[NJFAIL]

anyone able to help?

 

[ronv]

Maybe a latching solenoid would work better since you don't show anything to say the vent is open or closed or to tell a motor when to stop. More info would help. How far? How Hard? etc.

 

[MikeMl]

Modern cars are full of 12V reversible permanent-magnet gear-motors (door latches, seat adjusters, mirror adjusters, etc). Go visit a junk yard. You have to have the actuator in hand before you worry about designing the circuit...

 

[NJFAIL]

Well the idea is I want the vent to close to stop air from blowing through it. So it just has to close 'all the way'; a 'back' to the lid/closing part can stop the motor from pushing or it can just run for x seconds and it would obviously be closed.

I'm not sure how it should be executed, in my mind I thought I could just have a motor run for 5 seconds when a button was pushed, then it would run in reverse for 5 seconds when the button was pushed again. And that would close (push)/open (pull) the vent/lid. But then again I'm a noob to electronics.

Any help is appreciated!

 

[MikeMl]

No, you cannot do it with timers alone; you need limit switches which are depressed when the flapper arrives at the open and closed locations. Stalling the motor at the limits of travel is a bad idea. A slip clutch might work, but that is a mechanical nightmare.

 

[seanspotatobusiness]

How are you planning on installing the motors? Have you removed the dashboard? What will you attach them to?

 

[NJFAIL]

Yes, I removed the dash. I made a custom fiberglass dash board. I can fiberglass mounts for the motors. Attaching it isn't a problem.

how would I configure the limit switches?

 

[MikeMl]

Imagine two Normally Closed Limit switches; NC CLOSED LIMIT and NC OPEN LIMIT, a Double Pole Toggle switch and a reversing DC gear motor. When the motor runs to close the flapper, the flapper opens the NC CLOSED LIMIT switch. When the motor runs to open the flapper, the flapper opens the NC OPEN LIMIT switch. The DP toggle switch is lableled OPEN CLOSED. When the toggle switched is moved to the other position, the motor runs CW or CCW until the relevant limit switch is tripped.

 

[NJFAIL]

Thanks mike!

does anyone know of an online store that sells these limit switches/ motors.
Are there any special things I should look for? I assume not all motors are reversible, so I'd need to look for a reversible one. Any specific specs I should have for limit switches?

 

[MikeMl]

Allelectronics switches that can be used as limit switches.

Here is a motor. (read the description)

 

[Reloadron]

The limit switches you use will really be a function of the design as in how you mount them. They could be as simple as a normally closed push button switch or a micro-switch that has a lever. When the flapper reaches full travel in one or the other direction (open or closed) it will trip the switch opening the circuit. The mounting will determine the exact switch. Pictured below is a DPDT toggle switch, a simple normally closed push button switch and a lever actuated micro-switch.

Personally I would look to be able to mount a simple push button flavor as other limit switches can get more costly. The button switch and DPDT toggle can be had at places like Radio Shack but remember as to the button flavor you want Normally Closed.

The motor can be any 12 volt DC reversible motor but the caveat is you want a low speed gear motor. That can add problems and cost, An automotive motor would be a good choice if you can find one that will fit the mechanical design plan. Beyond that maybe a Google to find a parts house unloading DC reversible gear motors.

Again, most of this is how you can mount things in your scheme.

Ron

<EDIT> Mike was quick! </EDIT>

 

[NJFAIL]

can you edit my picture showing me how to wire it?

do you see any problems with it?

 

[MikeMl]

The DPDT must be a two-position toggle switch; not a momentary push-button. The mechanical position of the handle is the "memory" that determines the position of the flapper.

It can be done with a momentary push button, but then you have to add a indicator lamp to show the position of the flapper, and you have to add a relay as a "memory".

 

[NJFAIL]

I was thinking of using a button with 2 positions, "pushed" and "unpushed", the pushed position would be indented below the surface and the unpushed would be raised above the surface. What is a button like that called? I thought a momentary button was just one that has 1 default position, and it reverts back to the default position whenever pushed, but opens and closes the contacts.

Sorry I'm a novice, I've been trying to read up on electronics but I'm having a hard time comprehending it all. Thank you for your patience and help

 

[ronv]

You are doing good.
There are some nice small motors on ebay. type gear motor.

 

[MikeMl]

I was thinking of using a button with 2 positions, "pushed" and "unpushed", the pushed position would be indented below the surface and the unpushed would be raised above the surface. What is a button like that called? ...

I'd call that a mechanically latching push switch. That type will work in the diagram I posted, as long as it has two poles (six terminals).

 

[ronv]

Hook up

How it is actually hooked up will depend on which parts you get, but here is some info.

 

[NJFAIL]

All of the limit switches and toggle switches I've found are rated in 125+ VAC
Is this a problem for my DC application? Am I going to need a dc > ac converter?

 

[NJFAIL]

do I need another power supply (other than my 12v dc car batter)

or are there 12v switches that I'm not seeing?