Question DOF sfu units

Hi all,

Came across the DOF reality Sfu ballscrew unit for dc motors today and have a few questions

(These) https://dofreality.com/wp-content/uploads/2022/05/sfu-1024x747.png

Has anyone used them or have them?

Are they better than say 50 or 60:1 wormdrives?

What size motors are they using on those units?

And last but not least...Does anyone know if there is something similar around?

Thanks everyone

Hi
It,s better than a wormdrive, but going from linear motion to rotary motion isnt the best way.
You get better motion with a actuator but wont fit in there frame
regards ad

linear actuators do the exact same thing except the rod is directly connected to the ball nut. unless you are speaking to something different. the linear actuators I've seen have a rotary motor on them.

I am speaking something different , yes a ballscrew must turn by a motor to give linear movement
They put this linear motion up a leverarm and make rotary motion from it.
By every turn from a ballscrew you get the exact the same movement with rotary movement it works different
there is a angle comming in. To get it visual take a piece of paper and draw a clock on it draw one line from 12 to 6 o clock and then 5 horizontal lines from 1 to 11 /2 to 10 /3 to 9 /4 to 8 and 5 to 7 now you can see on the 12 to 6 line the movement every 30 degree and see there is a big difference in movement between 11 and 12 o clock and 3 and 4 o clock. with a actuator you dont have this
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Thank you for that explaination. That make sense now and also explains why they don't use the full 12-6 range or at least from what i have witnessed. The vertical motion from 12-1 and 5-6 is very little so it makes sense to not use those areas as the motor has to spin a lot for very little motion. I understand now. Glad we had this conversation.