Re: [CAD_CAM_EDM_DRO] Motor torque to linear force conversion?

> Hi list,
> How do you calculate the linear force that a particular motor/leadscrew
> combination will provide? For example, if I use a 400oz/in motor
> direct-coupled to a ballscrew with 4mm pitch what would the actual force be?
>

Think of the screw as a pulley with radius = lead/6.28 or about .64mm

Your 400 oz*in is 400 ounces at the surface of a pulley with 1 inch radius

Do the proportion: force*radius = force*radius

400oz * 25.4mm / .64mm = 15875 oz

15875 oz * .028 kg/oz = 444.5 kg, which is not a force unit, but
4356 N is. (Or in the units of my culture, we're talking ~1000 lbs)

(Another way of thinking of it: a 1 in pitch screw exerts a linear
force 2pi times its oz*inch torque. This screw has a lead 6.35 times
that. So the force is 400oz * 6.28 * 6.35 = 15951 oounces (yes, there
were roundoff errors in the first calculation)

Chris

--
Christopher C. Stratton, stratton@...
Instrument Maker, Horn Player & Engineer
22 Adrian Street, Somerville, MA 02143
http://www.mdc.net/~stratton
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