Tiny motor

I have an application for a tiny low-voltage, low-current, synchronous motor. Any idea who makes such a thing? I was thinking maybe the kind used in very small disk drives but I can't find a manufacturer.

On Fri, 11 Mar 2005 16:51:50 -0600, ROBERT ENDL top-posted:

... You might try some links here:

Good Luck! Rich

The pager motors are nifty, but I need tight speed control (a couple of thousand rpm), preferably without fancy speed control. Higher voltage/lower current drive would be nice. As would a 10 year operating life.

Price is "always" an issue. The Maxon EC series looks very interesting. Small, low power, and high speed. Maxon doesn't say much about driving them however. Probably rather sell the controller. It looks like I would have to generate a 3-phase...pulsed DC? Where can I find info on driving them?

martin

"An eye for an eye makes the whole world blind" Gandhi

There is a 'crossover' here in terminology. DC brushless motors, are in a sense very similar to synchronous motors, but with the excitation phases fed from a synthesised DC source, rather than a normal AC excitation. Most drive motors are DC brushless designs, rather than synchronous motors. For a genuine 'synchronous' motor have a look at SAIA-Burgess. Their 'URT' series motors, are 13mm*11mm, and run of between 3v, and 24v AC. EAD motors, do a DC brushless design in a very similar size.

Best Wishes

well, if money isnt a problem

martin

"An eye for an eye makes the whole world blind" Gandhi

Hello Robert,

They should help you with that.

Three-phase isn't hard to do. A shift register and a clock is one option. If you have a micro controller anyway and three free pins and a free timer you could have it do the control. But only some uC have enough compare registers for three-phase so the external solution is more likely. Then you'd have to shape the outputs and overlaps into whatever the motor wants (info that should be provided by the mfg).

Regards, Joerg

What is the price range of the Maxon DC brushless motors?

I've sent Maxon an email, but it's Saturday and I was just hoping someone might have some numbers already and would post them to the newsgroup, along with any other impressions of dealing with Maxon.

No Idea, havent used them since '93, servo motors on a motion control camera rig, ...and I didnt pay the invoice.

martin

"An eye for an eye makes the whole world blind" Gandhi

Is 1.9mm diameter smal enough? See "Product Range" -> "Micro Drive" on

Thanks. Turns out these guys do have the motor of my dreams, a very small, high-speed stepper. The price, $60/100s, might be a problem. I'm going to have rethink this.