design of a feed drive for an NC lathe

[kurthice]

Hi I'm new here. I'm pretty crap at mechanical design, but I have to design a feed drive for the X-axis of an NC lathe for a course project. I have to select the drive motor, ball screw, pulleys and timing belt. There are a lot of things i don't know, but my concern is how the pulleys can be connected to the motor shaft (can they be directly conncected to it) and to the screw shaft. I can select a ballscrew and a motor based on calculations, but the coupling of the elements is where the problems come.
For the screw shaft, I can choose between different end configurations, but i need a start point.
Do the pulleys require a key connention, or a press fit is acceptable? How can I connect the pulley to the motor shaft in the simplest way?
I apologize for the stupid questions, but I really need some advice.
Also, this is for a course project, and the simplest easiest solution (not necessarily working ) is what I'm truing to figure out.
Oh yeah, I forgot ..

[RICHARD ZASTROW]

kurthice, Try this www.jakobantriebstechnik.de

Dick Z

[Al_The_Man]

Keyed pulleys are one of the most common and secure methods, but if you want a method without having to machine keyways, using Taper Bushed pulleys are just about as secure.
These lock the pulleys by means of a taper sleeve using allen set screws to lock into place.
Type E or GF here http://www.martinsprocket.com/2001/SecKa.pdf#K5
If you also need any sizing assistance, here is an Free Engineering program that may help.
http://www.electromate.com/technical...morgansoftware
Al.

[kurthice]

thanks this is very helpful!
My greatest concern was how to secure the pulleys - I didn't know anything about the taper bushed pulleys.
Now I'll look for more information, like 3d models of such pulleys.
Is it ok to use such a pulley directly on the motor shaft?

[Al_The_Man]

Originally Posted by kurthice Is it ok to use such a pulley directly on the motor shaft?

My Excello Knee mills use this method and I have never had a problem yet.
They clamp directly to a straight shaft.
Al.

[kurthice]

Thanks a lot. I guess I'll be able to complete the design with this information