I was playing with a Chain and Sprocket assembly the other day and noticed that SolidWorks still doesn't have an easy way to link the Chain and Sprocket together so that they both move at the same time when dragged.

I have seen attempts at solutions to this problem using either Gear or Rack and Pinion Mates, however they are buggy and problematic.

I have found an OK workaround, so I thought I would share it.

Here is a summary:

•  Sweep a helix around a Chain Path using Twist Value and Revolutions
•  Mate a Nut to the Chain Path and Helix so that it moves along the path when spun
•  Mate the Nut to a Right-Angle Gear using GearMate
•  Mate the Right-Angle Gear to a Sprocket using GearMate
•  Mate the Chain to the Nut

Here is a screenshot of the assembly with everything shown...

Here is what the Lead Screw Nut looks like...

Here is the Right-Angle Gear...

When the Sprocket spins by dragging, the Gear Mate will spin the Right-Angle Gear, which will then spin the Nut. The Nut will then follow along the Helix, similar to a Linear Rail.

It is basically a curvilinear Lead Screw and Nut. Once this is modeled, the Chain can be mated to the Nut and all will be in sync.

I have attached a sample assembly for reference (SolidWorks 2020). Make sure and drag the red dot on the smaller Sprocket for best results.

If anyone knows an easier way, please let me know! Please share this model with others.

PS:

If you are wondering why there is an extra Right-Angle Gear mated to the Nut and Sprocket, it is because I found an anomaly with Gear Mates.

If the Nut is mated perpendicular to the Sprocket with a GearMate, the rotation of the Nut will speed up and slow down according to the size of the curve it is travelling on. It is a very strange thing to see.

Thus, instead of mating directly to the Sprocket, I had to put a 'middleman' in there.

The Right-Angle Gear ensures that the Nut has a parallel GearMate instead of perpendicular.

Not sure if this should be reported as a bug.