Convert motor torque into linear force:

[eloid]

I found this formula to estimate linear force developed using a screw / motor combination:

1. Convert ballscrew lead to equivalent pully radius:
example:
Lead =0.200
0.200 / (2pi) = 0.200 / 6.283 = 0.0318" (equliv. radius pully)

2. Convert motor torque into linear force:
example:
Torque = 100 Oz.-In.
100oz-in / .0318 in = 3144 oz. (linear force)
3144 / 16 = 196 lb (linear force)
196 * 0.8 (efficency for ballscrew) = 157 lb linear force.

If this formula is correct, a 100oz-in motor and a 0.200 screw can push 157 pounds force."


so if your not useing a ball screw do u just use thread per inch instead of that .2 use in the above eg?

how does this change if u plan to use 4:1 gear ratio?

[NC Cams]

You forgot loss from coefficient of friciton - probably negligible in a ball screw.

A 4:1 gear reduction will increase the force driveable by the motor a factor of ~4 times MORE with a speed decrease of ~25%

[Al_The_Man]

Originally Posted by NC Cams You forgot loss from coefficient of friciton - probably negligible in a ball screw.

There is a mention of ballscrew efficiency (*.8)??