Newbie with alternating ON Off DC Gearmotor circuit help.

[huse0054]

Hi There, I am curious if anyone would be able to help me in providing some circuit design ideas. I am a begginer with circuits and electronics and have created some circuits from online and book sources etc.. but not quite to the point of knowing enough to "design" my own. I need to make a circuit that controls a 6-12 volt DC gearmotor and it needs to do the following.

When a switch is flipped:
-Gearmotor turns on in one direction for 30 minutes.
-After 30 minutes the gear motor shuts off for 4 hours
-after 4 hours the motor turns back on again for 30 minutes but with the opposite polarity (direction)
-this process completes itself untill the switch is flipped to the off position.



Any help would be appreciated.

Thanks

 

[ronv]

Help us a litttle with the final application so we will know if it is ok to have it run for 30 mins. in one direction and 31 mins in the other. Stuff like that. Also need to know the current required by the motor.

 

[huse0054]

gearmotor

This will be for an automatic watch winder I am trying to make. For wear and tear reasons I would like to only have a it run a max of 30 minutes at a time and then switch directions every 4 hours or so.

I have not picked out a gearmotor yet but it needs to be as small as possible and turn at a max of about 10RPMs and be 12 volts or less.

Here is one I have been looking at and any other suggestions or places to find a gearmotor with those specs would be appreciated as well.

**broken link removed**

As far as current, not sure, maybe 100 mA at least thats waht the specs for the above motor says.

Thanks

 

[MikeMl]

Instead of using time to control the duration the motor runs, it is preferable to use "limit switches" to stop the motor when its output reaches mechanical limits.

 

[mbarazeen]

-this process completes itself untill the switch is flipped to the off position.

you mean it will continue 30min & 4hr operation until the switch is flipped to off? or its only will go upto one cycle as you explained? also what would happen if teh siwtch is turned off when its in between?

 

[SABorn]

Why the heck would you want to wind a watch backwards after 4 hours?
I thought a watch only wound one way??

Personally i would use a micro controller to run the operation and count the turns as well as to control the timing period.

Pete.

 

[huse0054]

Not sure how else to explain it....
Automatic watches are wound by wearing them on your wrist, the movement of your wrist winds the watch and it can be wound in any direction. There is a counterweight in the watch that can spin either direction. The watch stays wound for 1-2 days after you have stopped wearing it so a watch winder can be used to keep the watch wound while not on your wrist, thus not having to reset the time. Many commercially available watch winders will spin the watch in both directions to avoid exccessive wear from the counterweight spinning the same direction.


A watch winder also does not need to run continuously as mentioned before, it needs to run for a "short" period of time 30 minutes or so. Rather then me turning the machine on and then off after thirty minutes, then wwaiting for 4 hours and reapeating the process I would like to have that process animated.



I have no idea how limit switches would accomplish this, are they not mechanical switches that are touch activated?

If the switch is turned of in between cycles then I suppose it would be preferable to have the timing cycle reset so that the next time it is flipped on it starts winding the watch again for 30 minutes from the beggining. But not a must as I would be willing to do whatever is easiest or feasible.


Microcontrolers I have not used before but would be willing to learn,Arduino right?

Thanks, here are a couple of examples of what watch winders look like.

YouTube - Watch Winder KUNSTWINDER 2 watch winder
YouTube - Automatic Watch Winder

 

[huse0054]

Watches wind both ways, some wind clockwise and others counterclockwise. Plus it would help with wear and tear so that it wasn't constantly spinning in one direction.

And yes it would be on for 30 minutes and then shut off for 4 hours and then turn back on in the opposite direction for thirty mintes and then turn off for 4 hours and then back on in the opposite direction for 30 minutes and then off for 4 hours etc.......... this would repeat itself as long as the switch is turned on.
If the switch was turned off during any of these cycles I idealy would like it to restart itself from the beggining if possible.

Maybe I am in over my head but would like to try and make this work even if it means trying to learn microcontrollers.

I am not sure how limit switches would work in this application.

Any help would be appreciated

Thanks

 

[mbarazeen]

There is a way you can do it using 4017 counter, see the attached cct. you need to have a timer to give a pulse every 30min to clock the counter.

The out put is just defined as forward and reverse, need some modification depends on what you are going to use at the end to drive the motor.

if you want to go with PIC option, some one can help you...

 

[huse0054]

Thanks Mbarazeen, Not too familiar with all that your schematic entails but it will give me some learning to do

What casues the polarity to switch and is the 4 hour off period built in?

 

[Mr RB]

Watches wind both ways, some wind clockwise and others counterclockwise. Plus it would help with wear and tear so that it wasn't constantly spinning in one direction.

...

From what I know about auto-winding watches they have a rotating weight, and a ratchet. So to wind both CW and CCW types of watch, all you need is to rotate a bit, then back a bit.

I don't know how many degrees you need to rotate for the ratchet pawls to re-engage but it's probably a lot less than 90 degrees.

You may be able to make something that just rotates back and forth 180 degrees based on limit switches. Then you could turn it on with any automated timer for 30 mins every few hours.

 

[mbarazeen]

What casues the polarity to switch and is the 4 hour off period built in?

little explanation may help you...
when the switch is toggled... the timer starts to count 30sec to deliver a pulse..
reset of both 4017 goes low so that it is active...mean time "reverse" out will go high....
when 30 min is over timer gives a pulse & increment the 1st 4017(above one) making "reverse" to go low..
the counter keeps on incrementing for another 30minx8 (= 4hr) until the counter get a reset...this time counter #2 will increment making forward to go high... until next 30min pulse and wait for 4hr to get a reset....

the cycle continues until you put the switch off.... when you start next time it start from beginning.

Edit: on my diagram mistakenly i swapped reverse & forward...but will not make any difference...

 

[huse0054]

Thanks Mr RB for the info on using limit switches that does make sense however I am trying to be very specific in what I need it to do.

I am currently baseing my design on one I found online. The Kunstwinder, it is also on youtube. I am using CAD and will then machine it out of stainless steel. It winds two watches at the same speed being driven by one geared motor and a couple of timing pulleys and belts. I have it all designed and it works in Autodesk inventor and the next month I will start machining all the parts. I guess I am making more than just a simple watch winder I also want it to be a work of art and something that is "cool" and lasts a long time.

I am trying to simulate the on/off characteristics found on their website.


I am much more versed in CAD and Machining than I am in electronics and circuits, thus why I am asking here in the forum for help.

It would also be nice to incorporate the following but as is probbaly pretty apparent I am fairly new to electronics so getting the basics is fine for me now!

Wishlist:
1. An LCD screen that displays how many rotations it has completed a day/ how many RPM's it is currenlty spinning.
2. Some LED lights for looks
3. Incorporate a second geared motor to spin the entire base
4. Have it operate off of an AC wall adapter as well as batteries.
5. And anything else I can think of to make it more complicated....LOL

 

[huse0054]

Thanks for the explanation mbarazeen that helps! I will give that a shot and I am sure I will have many more questions.

What did you mean when you said it will need modifications depending on what I use to drive the motor?

It is just a simple 12 volt geared motor drawing about 100MA.

 

[mbarazeen]

1. An LCD screen that displays how many rotations it has completed a day/ how many RPM's it is currenlty spinning.

you can think of step motors for more accuracy...

 

[mbarazeen]

What did you mean when you said it will need modifications depending on what I use to drive the motor?

It is just a simple 12 volt geared motor drawing about 100MA.

you may go for a relay at the put put..or even direct drive via transistors.. why even you can select a driver IC...

 

[huse0054]

In the circuit diagram what is the 30 minute timer V3? Is that something you can buy or does it need to be made? I tried looking online for it with no luck.

Also what are all those other half ovals? Would anyone be able to explain what each compnent is and its function? Or direct me somehwere that could refrence what they are?

Thanks

 

[bryan1]

Hi huse0054,
I've approved all of your posts and hopefully you are over the moderation period That Kunstwinder clock winder does look cool, now by timing how long it takes to do one revolution then using a 16f pic it would an easy one to do. The off time can also be programmed in. So if you want to start learning pic's this would be a great start and I'm sure we'll help you with any code or any other thing needed.

Regards Bryan

 

[huse0054]

Thanks Bryan,
I know nothing about PICs but definitely would like to learn and I also do not know any programming unless the little bit of pascal I took in high school counts

So next step would someone be willing to point me in the correct direction to learn more? Maybe recommend a Pic to purchase that would fit the following requirements?

- be small and relatively cheap
-easy to learn for a complete novice in programming
- able to drive two identical motors at 12 volts and about 100ma for the given time periods I mention in the previous posts.


Anything else I should be aware of? Also what does 16f mean?

If you havent noticed yet I knowofo much that stuff needs to be explained to me like I am in the 1st grade lol!
-

 

[huse0054]

Can anyone provide me with help or direction, I feel that this should be an easy setup to accomplish I just don't even know where to start.

Thanks