Does it exist?

[stevespo]

I'm looking for a brush DC servo, NEMA 23, with stats something like:

150 oz/in continuous torque, maybe 450-600 oz/in peak
max 1800 RPM
compatible with Gecko 320/340 drivers (20A 80VDC range)

Do they exist? I'm considering a motor upgrade, but would prefer to direct drive my 5 TPI ballscrews and not mess around with belt reduction. Most small servos have a much higher top speed and require reduction to limit speed and gain torque.

I've done some searching online, but really don't know where to look.

Thanks for any pointers,

Steve

[stevespo]

Maybe I'm barking up the wrong tree?

Are these capabilities possible with a small DC servo? I know that I can reduce the RPMs on many common models and get this kind of performance, but are there other options?

Thanks,

Steve

[Al_The_Man]

You most likely will find that DC servo's in NEMA 23 will top out around 100 0z-in continuous.
Al.

[stevespo]

Al, that's kind of what I have discovered. I did find a brushless servo (Nema 23) capable of 141 oz/in continuous, but that's about it so far.

The most common DC servos seem to be 42-50 oz/in continuous and 350 oz/in peak. I don't have any hard data, but I believe this is a bit marginal for my machine, unless I reduce RPM to gain torque.

My belief (based on my 425 oz/in stepper torque curve) is that 100 oz/in continuous would be adequate for driving my gantry, particularly with a decent peak available when needed.

So, I can reduce a 50 oz/in 2:1 or even 3:1 to gain the torque - or I can try to find a 100 oz/in continuous and direct drive it. In the interest of simplicity (and laziness) I'd like to go the direct drive route. I'm just having no luck finding a suitable motor.

Thanks,

Steve