On Thu, 31 Jan 2013 13:49:03 -0800, Paul Drahn
wrote:

On 1/31/2013 9:20 AM, wrote:
I am working on a 5th axis for the mill. I think it will need a brake.
I'm not sure if the servo motor will be able to hold position for some
operations. I have looked at magnetic particle brakes and they ain't
cheap. So I'm thinking about making one. Or some type of
electromagnetic brake. The brake, when actuated, must not cause any
motion of the axis, and I'm just not sure what would work best.
Eric
You might investigate the magnetic clutch on an automobile air
conditioning pump. That has bearings, and a really strong 12 volt
electromagnet. A good start for you, anyway.

THOSE I'm familiar with. The action might cause a rotational hit since
the clutches are usually on spring-steel strips. But they're strong
once engaged.

I was thinking disc brake style, too. The disc would be mounted to
the lead screw (if there is one) and opposing solenoids would grab it
from either side.

Eric, if added mass wouldn't be a problem, might you increase the
servo size, resulting in a higher holding capacity and bypassing the
need for a brake?

--
I’ve long been passionate about protecting and expanding democracy,
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distribute power from kings to the rest of us.
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