Servo as a spindle drive motor

[Allyd1964]

Hi all, can a servo motor be used as a spindle drive motor. I have never seen one used and for the life of me (or is that my limited knowledge) I can't work out why. I've googled it but nothing comes up that even points me to the right answer.

[ger21]

Yes, they can. You probably don't see them often because powerful servos can be pretty expensive.

[Karl_T]

Did you know you can make an ordinary DC motor into a servo motor? This idea would work well for a small hp. spindle drive.

http://www.truetex.com/servomod.htm

Karl

[vger]

A servo motor's maximum RPM may be a limiting factor if you are direct driving.

I considered using a vacuum cleaner motor as a spindle motor. Reasonable power and high RPM. Speed control is easy with an autotransformer.

Steve

[Al_The_Man]

Originally Posted by Allyd1964 Hi all, can a servo motor be used as a spindle drive motor. I have never seen one used and for the life of me (or is that my limited knowledge) I can't work out why. I've googled it but nothing comes up that even points me to the right answer.

I have used both DC brushed and BLDC servo's for this type of app.
If you use a Brushed servo, you can use the cheaper SCR control as made by KB , Baldor etc, these generally have the tach option included, and many DC servo's have a tach, this enables quite precise speed control.
If you get one that is a bit higher torque than normally needed, you can gear up to get the higher speed, DC servo's are usually restricted to 3000rpm BLDC go up to ~6000rpm.
Al.

[salzburg]

I have 3 big servo motors, brushtype,probably very old. For an experiment
I hooked one up to an 180 V dc drive and at that voltage the motor
turned 7800 rpm. At that point the little generator winding at the back
of the motor started to smoke and I shut it down. The motor windings
were fine. My opinion is that any of these motors would make good
spindle motors. It probably would not be wise to run them at that high a
voltage.