can you control the speed of an electric motor through circuitry

[nodijodi]

I am building a prototype device and need to control the r.p.ms of a 12 volt motor,basically I have a motor from a variable speed drill and I hoped to control its speed by useing the trigger switch off the drill but because i need the motor to run at low speed for extended periods the trigger switch creates too much heat and burns out. I was wondering wether the speed could be controled through circuitry

 

[jpanhalt]

A little more information would help. 12V drills are becoming pretty rare. The speed control should work with proper heat sink or maybe a little beefing up. So, you already have the circuitry.

As for running for long periods, the limiting factor may be the drill motor itself. It is not made for continuous duty.

John

 

[nodijodi]

Controlling speed of an electric motor through circuitry

thanks for that John,

so I need a 12 v motor that will run for extended periods. It will be powered by a car battery, can you suggest what sort of motor I should be looking at?

 

[gerty]

While you're taking the battery out of thr car, grab the windshield wiper motor also..

 

[Sceadwian]

Seat adjust and window motors from a fully automatic car too =)

 

[jpanhalt]

You need to define the power and speed you need. Does it really need to be continuous duty? Short duty cycle, high-power motors are common, fairly small, and cheap. By comparison, a 1/3 HP, continuous duty DC motor may be 5" diameter, 8" long, and cost over $100 USD new.

For starters, check out the surplus dealers. An automotive fan or wiper motor might work.

John

 

[AllVol]

I need a 12 v motor that will run for extended periods. It will be powered by a car battery, can you suggest what sort of motor I should be looking at?

I understood you already had the motor, but just needed a speed control circuit. Google "motor speed control". You'll find a plethora of circuits there. Actually, a simple 555 timer can generate a pulse width modulated signal that can be varied to control speeds in certain applications.

 

[flat5]

Buy a better drill.