Motor control circuit 5

[crunch53]

Ok , I’m going to post this question again. The last time I posted this I couldn’t get a schematic of a circuit that I could use that was simple. Maybe by not wanting this thing to do so many things it will help. I am not familiar enough right now to work with PIC’s etc ant this should be a fairly simple circuit that could probably used a 555 or such which I understand a little bit. Right now I won’t make it do too many things at once. Here is what I need.
1. I have a small geared motor that’s 6 volts DC. No load is about 65 milliamps and with a load I can get it up to around 90 milliamps. I have a pushbutton and let’s say that I want an led on and sitting next to the pushbutton. I push the button and the shaft of the motor turns 1 time and stops until the next time the button is pushed.
2. Same scenario except the motor runs for 30 seconds and stops until button is pushed again.
3. Same scenario except no switch to push. The motor just runs for 30 seconds and stops for 1 hour and keeps repeating the same thing. Any help is greatly appreciated.

Thanks,
Mike

 

[felixc]

Since you are familiar with a 555, the 555 can sink or source 200mA, so it can be enough to drive directly your motor, if it really consumes only 90mA. Try it as such to keep things simple first. If if needs more, then you'll need ane xternal transistor, or a logic drive mosfet, to drive it.

The rest is only a matter of choosing the right RC combination for the 555 to do what you need. You configure it as a monostable for the first two needs. 30 seconds is in the range of what the 555 can do.

For the third scenario, a one hour delay is too long for a 555. You'd need something like a 4020, but try fiddling with the fist two scenarios first.

 

[zeitghost]

Last time I worked with a small dc motor like that, the startup current was in excess of 5A... and the switch off spike exceeded 100V.

A driver transistor is strongly recommended.

Is your first applicatation a requirement that the motor turns exactly 360?

 

[crunch53]

No it doesn't need to be exactly 360. Nothing in this curcuit needs to be precise.

Mike

 

[fsmyth]

Do you need to do all 3 at the same time?
If yes, build a 30 second timer (555), add a
single-lobe cam to the motor shaft with a
micro-switch, and build a 1-hour timer (4017
or such). Connect inputs appropriately.
If not, things are much simpler.

There are some related diagrams at:

http://people.txucom.net/fsmyth/pages/555apps.html

and

http://people.txucom.net/fsmyth/pages/555apps.html

Pick and choose. Mix-n-match.
<als>

 

[crunch53]

No they don't all 3 need to be the same circuit. Whichever way is simpler.

 

[crunch53]

Here is a drawing to give you an idea of what I'm looking for.

http://us.f2.yahoofs.com/bc/401d958a_3e8a/bc/Public/Threaded+Motor+Circuit2.jpg?bfNLKeDBdaDcY7xb

 

[fsmyth]

Well, your link does not seem to work.


Just found out that MY page jump link was broken
Go to:

http://people.txucom.net/fsmyth/pages/555apps.html#555expr1

Look at the diagram directly above it. Modify R4/C2 for
appropriate timing- something in the order of 1M/2.2uF.
Or 2.2M/1uF. Add the cam/microswitch to the motor shaft.
Takes care of (1) and (2).

For the long delay version, see:

http://people.txucom.net/fsmyth/pages/555apps.html#555apps6

Set the 555 timing for 0.1 second period. Connect to the
appropriate counter output; Q12 (or Q13, if you use a 4020).
Takes care of (3).

 

[crunch53]

Very good! From what I can see right now I think those are exactly what I’m looking for. Just to make sure were talking about the same ones they are Timer Control Board Schematic and Plant Watering Timer - Hours of Delay. Here is one last twist on the circuit if you want to look into it.

http://www.eng-tips.com/viewthread.cfm?qid=137033

Is my ling broken? I can get to it. If so where can I upload the files?
Here is another one I was looking into but never got too much help on without everyone wanting to add encoders or using PIC’s etc. I’m not opposed to using them but I just think their overkill for this and I don’t understand them very good.

http://us.f2.yahoofs.com/bc/401d958a_3e8a/bc/Public/Threaded+Motor+Circuit1.jpg?bfJIheDBbab56G6v

Thanks a lot,
Mike

 

[fsmyth]

(1) Yeppers.

(2) Your application(s) seem to be changing
The micro-switch suggestion assumed that you wanted
the motor to stop at the same point every time. If
this is not the case, then everything could be done
with timers. The microswitch could be replaced by
a LED/LED sensor assembly (adds a bit of complexity).

(3) Apparently. Looks like yahoo re-directs failing.
Never had much luck (or patience) with yahoo or
microsoft net crap. My ad blockers and pop-up killers
make most of that genre unusable.
Someone (jraef? skoggs?) posted a pointer to a web
site dedicated to image and file upload/storage. I
even signed up for/on it, but can't find it now.
An old age/memory thing. There are any number of
(free) do-it-yourself web hosting sites. Some better
than others. Google would be your friend here.

(4) Someone must be editing my posts. I KNOW I put
a mangled email address in one of them. Use the
email address on one of my pages; change any reference
to "txucom.net" to "consolidated.net" (I left the old
ISP name on the pages - it has cut down considerably on
spam reception Send me the image the URL references.

<als>

 

[crunch53]

Your sugestions seem to be just what I'm looking for. I want to keep this as simple as possible. I will try 4 and see if I can get you the immages. maybe that will clear things up a bit more.

 

[crunch53]

I tried but I don't think it worked.
I'm going to do something but I'm not sure if I'm supposed to. It can be very hard to explain things without pictures and you can't include pictures in the posts here. Here is a site where I did post the message with drawings. If this makes it try looking there. In the meantime I'm going to see if there is one or if I can start a simple site to where everyone can post pictures to easily and get them.
Mike

http://www.electro-tech-online.com/viewtopic.php?p=115025#115025

and

http://www.electro-tech-online.com/viewtopic.php?p=113464#113464

 

[fsmyth]

Don't bother to email 'em.
In your second drawing, put limit switches on each end
of the "traveler's" path. Use this to stop and/or
reverse the motor.
Add one microswitch to a cam or notch in one of the end
plates. Count the pulses. Trigger at 5 (or whatever).
Use relays and/or transistors to control the motor.
**Simple.
You may replace physically operated switches in both
of the above with LED, lamp, or magnetic sensors.
Not as simple (needs drivers and interface components).
**Still pretty basic.
Control everything with a dedicated, programmable
micro-controller. Still needs sensor inputs.
**A little more involved.
Modify something like a (purchased) lawn watering timer
panel. Possibly parallel outputs for different timings.
Resolution will be a lot coarser than above suggestions.
**More than a bit involved.
Pay someone to design and/or build your device.
**Easiest of all.
<als>