Screw drive motion

[Anonymous]

Hello everyone,

I have an assembly of 3 different parts: a grounded "Base", a "Shaft" and a "Roller".

Basically, this works like this: while the shaft rotates (the only allowed movement), it pushes the roller upwards. The roller is allowed to move up (or down) but also to rotate around its own Z axis, to supposedly reduce friction between the contact surfaces of shaft and roller.

The Shaft is a trapezoidal screw drive, with 9mm pitch, and the roller is custom made to fit the shaft, with several circular grooves.

My issue at this point is to replicate that behaviour in Inventor. I've tried several ways but I just can't figure out a way of simply put the shaft rotating and, when it contacts with the teeth of the roller, it will push the roller upward.

Until the moment, I was not able to create a constraint or joint that would do that and the roller teeth usually end passing through the shaft teeth, what would be impossible in a real model. In the attached file, there is a .gif which shows what I'm trying to explain.

If someone has a solution, I would be pleased to read it! I've also attached the assembly and the part files, if someone is willing to give it a shot.

Thanks in advance!

[mcgyvr]

Inventor version?

Do you have dynamic simulation?

In general ".zip" is a much more accepted compression format.. RAR extraction tools cost money so everyone typically just uses zipped files which windows does by default.

Example:.. I can't open your file at all as I don't have a RAR extractor.

[JDMather]

Rotational/Translation constraint in modeling environment (generally with a driven Angle constraint).

or

Screw Joint in Dynamic Simulation environment.

I don't have an rar extractor - so I can't look at your actual files.

Microsoft Windows includes a zip file compressor.

[Anonymous]

Oh, sorry about it!

My Inventor version is 2016 and yes, I have Dynamic Simulation.

The files in a .zip format are in this post. I will replace them in the original post aswell.

[JDMather]

Sketch 1 in your Base component does not have any dimensions - yet if I dimension the sketch it comes out to perfect dimensions.

What happened to the dimensions?

Why was the rectangle made with more than 4 lines?

I just added a Rotational/Translation constraint - and it worked fine.

Find the Drive This constraint in the Relationships folder.

Right click on the constraint and select Drive Constraint.

Click the Play or Reverse Play button.

[Anonymous]

Thanks for having a look at this!

Can you show me how? I've tried Rotational/Translation constraint several times and never got it working. Maybe I'm just doing something completely wrong.

[Anonymous]

I've done that and I can't drive the constraint. I just can't select it.

[JDMather]

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@Anonymous wrote:

... I just can't select it.

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I don't know what this means.

Create a Screencast Recording of what you are doing.

Are you using the files that I attached above?

[Anonymous]

Hey JD,

I was missing the fact that you had uploaded a self-explainable file! Thanks!

I have another couple of questions, although:

In your file, the roller and the shaft are actually not touching. Is there a way I could do this? Basically, i want to improve the dimensions of the roller teeth, making it as bigger as geometrically possible. It would be helpful I could get them in contact so I would have more space to it.

How could I simulate the rollers rotating around their own Z axis, while travelling with the shaft?

Thanks again!

PS: Sorry for the third post in a row.

[JDMather]

Hmmm,

For me to do much more with this - I would have to clean up all of the files (not because that has anything to do with the solution, but I just can't stand messy work).

I would start over with the Base part centered at the origin.

I saw tons of extraneous work axis and other geometry that would not allow me to sleep at night.

Can you start over?

[Anonymous]

Yes, I will upload new files. 

Thank you very much, once again.

[Anonymous]

Hello again, JD.

In the attached file, there is a new file for each component and an assembly. I hope you can help me with the questions I've mentioned before with these files.

Thank you!

EDIT: Well, adding a Rotation/Rotation constraint, I could put both shaft and roller rotating in opposite directions without problem.

Now, my concern is to get them in contact like shaft actually pushing the roller.

EDIT2: Is this possible to recreate also in Dynamic Simulation? And then export to stress analysis further? I've never worked with Stress Analysis before so I don't know if I can go to it from the Modeling view.