Category Archives: Chemical

Ball Screw Solutions for Long Travel & High Speed

Design World’s always excellent Danielle Collins posted a great article about how Design Engineers can achieve both high speed and long travel with Ball Screws.

Didn’t know you could do that, did you?

Traditional solutions involve Belt Drives, Rack and Pinion Systems or Linear Motors. But each of those come with their own set of drawbacks. Ball Screws are an ideal solution for applications that are sensitive to thrust force or positioning accuracy

Yet Ball Screws are rarely looked at for high speed/long travel applications. Why?

Critical Speed

Any long cylindrical object will naturally sag in the middle. Add rotation, and you will get a whip effect, similar to a jump rope. The speed of rotation where that effect starts is the Critical Speed.

Obviously, one way to limit this effect would be to have a shorter unsupported span. But how do you limit the effect if your application calls for a long travel span?

The Solution – Ball Screw Supports

ball screw supportsSome customers have made their own ball screw supports, usually paired on either side of the ball nut in pairs of 2, 4 or 6, to reduce the unsupported distance, essentially quadrupling the critical speed for each pair used. Depending on the application, they can even allow you to select a smaller diameter ball screw, without compromising performance.

So, have you used this solution? Or do you have an application where it might be a suitable alternative?

3D Printers – Leading the 3rd Industrial Revolution

Late last year, Design World editor, Danielle Collins, posted a great article about the “3rd Industrial Revolution.”

News flash—we’re in it, and 3D printers are leading the way.

Costs are coming down almost as fast as accuracy is increasing. From the industrial creation of finished parts, to the maker movement-led DIY creation of home models, 3D printers are increasingly becoming a more viable technology across different industries and applications.

Collins sorts printers into 3 basic categories, each with unique offerings and challenges:

  • Desktop
    • Generally 10x10x10 or smaller.
    • Low cost kits to fully assembled models.
    • Utilize FreeForm Fabrication, or FFF for printing.
    • Relatively low-tech linear motion solutions; typically round shafts or belt-pulley systems.
    • Prone to alignment issues, such as binding and torque spikes, as well as backlash.
  • Prosumer
    • Print areas around 18x18x18.
    • FFF or Selective Laser Sintering (SLS) methods of printing.
    • SLS offers more material choices including metal, ceramic and plastic.
    • Ideal for part modeling or rapid prototyping.
    • Rely mainly on linear rails and lead screws.
  • Professional/Industrial Grade
    • Print areas of up to a cubic meter.
    • FFF, SLS, Stereolithography (SLA) or in some cases unique, proprietary, deposition methods.
    • Highest resolution (layer thickness) as well as better surface finish and faster build times.
    • High-precision parts, functional prototypes, finished parts and printed electronics.
    • Utilized the most advanced linear motion solutions. But Collins notes that even these might not be accurate enough for some projects, and custom solutions will become necessary.

This handy chart, also from the article, helps lay out the features of all 3 types (click for a clearer view).

NOO-040_Chart

So, what has your experience with 3D printing been? Are you using them at all, investigating the options or already incorporating them as a part of your business?