Basic Variable Speed Motor/Switch

Not at all hard to do, but the size (power) of the motor and the type / rating of your available power source makes all the difference.

hai,

if you like to make variable speed motor have 2 alternative. the first you can put the gear for madification speed motor. the second you can use electronic circuit to reduce the speed, this circuit for reduce speed motor operated in voltage or current.

Hello Engineered By God

I do like your artwork.

If you advise the intended use for the variable-speed reversible motor, it would be easier to assist.

You refer to: <"....a De Walt cordless drill....">

Not every motor is capable of being easily reversed.

Some Universal motors (like the De Walt drill, may be reversed simply by a switch which swaps the brush connections over, while other Universal Motors shower sparks from the brushes if the brush connections are swapped.

You are requiring <"...the motor to operate at these somewhat precise varying speeds when I move the lever one way, but is it easy to then get it to reverse rotating direction with the same lever, with the same precision....">

As I said earlier: If you advise the intended use for the variable-speed reversible motor, it would be easier to assist.

Looking forward to your reply, with

Kind Regards....

Hopefully this is adequate.

What voltage and what type of voltage, AC or DC? Without such answers we cannot accurately help!!!!

Honestly, I'd use whatever voltage the motor/switch is. If I can easily acquire a 12vdc motor that will accomplish my goals, I'll use that. The object that I'm rotating in my second illustration weighs only about 2 lbs. I'm asking you guys what type of motor I should look for. I will need to make about 12 set-ups like the one I'm envisioning, so they have to be something I can buy 12 of.

Were it to be a 12VDC model railway locomotive, then the ECM Compspeed CB feedback controller, with forward and reverse on the same knob, would do this for an initial investment of around £15-20GBP via on-line auction sites; sadly the CB is no longer manufactured, though it may be had secondhand.

Perhaps the easiest way to do this would be to find a used variable-speed reversible drill and take it apart. You might be able to find one that somebody dropped and broke the case...try checking local repair or construction/installation people. At least this way you know the speed control is properly sized to the motor, which might not otherwise be the case.

Your art work is way better than none!

Dick

Depending on your experience with electronics it is fairly easy to construct a Pulse Width Modulator circuit from a pair of 555 timers or a 556 chip. This would give you very good control of the speed of a standard DC motor. If you pair this with a standard H Bridge circuit you would have direction control also. The total number of parts would be minimal but it does take some electronics knowledge and tinkering.

Here are a few websites that may help you out;

http://www.dprg.org/tutorials/2005-11a/

http://www.pcsilencioso.com/cpemma/555pwm.html

http://www.mcmanis.com/chuck/robotics/tutorial/h-bridge/index.html

http://www.instructables.com/id/How-to-make-an-H-bridge/

Good luck,

Doug

CR4 Admin: removed broken link: http://www.dprg.org/tutorials/2005-11a/

Only if the motor is reversible, some universal motors will only turn in a particular direction, no matter what the polarity of the supply is.

Furthermore, we do not yet know if it will be connected to an AC or a DC source or the voltage level of that source even!!!

Your ideas are only good for DC and motors with permanent magnet fields.....

I know you meant well but.....

Go to Grainger.com or McMaster Carr.com ........cataloge.

AC and DC stuff avilable...any quantity.

MR. GUY

You may have answered your own question.

I've seen 14.4v & 18v reversible dual range variable speed cordless drills selling for under $20 Can.

I'm sure if you looked on the net for import distributers or on eBay you could strike an even better deal for the dozen you are looking for, and adapt them or their guts accordingly.

The technology is so developed and mass-produced you would be hard pressed to get the raw materials for this money.

It may well be your cheapest and easiest route.

Besides, it's what MacGyver would do.