cam and cam follower constranit

[arman.tale]

Hello,

I am making a 4 cylinder engine assembly and i am having difficulty for constraining cam with the cam follower. when i use transitional constraint, by rotating the cam shaft, the follower goes inside the cam and by using any other constraint it does not simply work. the attachment is the photo of the cam shaft and the followers in the assembly. I appreciate if someone can give me a solution to this annoying problem.

Regards

Arman

[JDMather]

Can you attach your assembly here?

What version of Inventor are you using?

[johnsonshiue]

Hi! Cam and follower constraint in Inventor is fulfilled by Transitional constraint. If I were you, I would create a zero offset surface (Thicken -> Surface -> offset = 0) on the Cam faces and extend it on the sides. Next, create Transitional constraint between the follower (moving face)  and the Cam zero offset face (transition face). After the relationship is established, you can hide the zero offset surfaces.

If you post the assembly here, I can help take a look and comment specifically.

Thanks!

[arman.tale]

hello,

I appreciate your help. the attachment is the assembly file. please check if you can access it or not!

Regards

[arman.tale]

please ignore the above reply. i do not know how to send the assembly because they all related to the part and the project, and i cant send the pack n go because of the size. please find the attachments which are the cam shaft and cam follower part. can you figure out how to constraint them. BTW I use version 2014.

[arman.tale]

Dear Johnson,

thanks for your reply. i still dont understand. i dont know how to send the assembly here but i attached cam shaft and cam follower parts. i appreciate if you can take a look at them and help me to findout how to constraint them.

Regards

[johnsonshiue · Accepted solution]

Hi! You did not attach the full dataset with all the referenced ipt and iam files. The best way to upload a dataset is to right-click on an assembly file -> Pack and Go -> point it to a folder. Then zip up the output folder and upload the zip file here. Anyway, I think I know what you are trying to achieve here. Please take a look at the attached image. It explains what I described earlier. Once you are done with a pair of cam and follower, you should be able to do it for other pairs. Take a look and let me know if you have any question. Thanks!

[johnsonshiue · Accepted solution]

Hi! There was an issue with the thread or something. I was not able to attach a file. The image explaining the solution is attached.

Thanks! Sorry for the confusion!

[JDMather · Accepted solution]

Download the attach *.zip file.

Right click on the attached *.zip file and select Extract All.

Open the assembly file.

In the Relationships folder right click on the Drive This constrant and select Drive.

Click the Play button.

Is this what you are after?  (Have you installed all Service Packs and Updates for your version of Inventor?)

[JDMather]

....then check out this example in Environments>Dynamic Simulation.

If you graph the Acceleration curve of one of the Prismatic Joints - I think you can create a better cam using the Cam Generator Design Accelerator within Inventor.

I just noticed that I have a couple of mistakes - but you should be able to figure it out from here.

[admaiora]

"

Hi! Cam and follower constraint in Inventor is fulfilled by Transitional constraint. If I were you, I would create a zero offset surface (Thicken -> Surface -> offset = 0) on the Cam faces and extend it on the sides. Next, create Transitional constraint between the follower (moving face)  and the Cam zero offset face (transition face). After the relationship is established, you can hide the zero offset surfaces.

If you post the assembly here, I can help take a look and comment specifically."

Nice tip Jhonson thanks!

[SER4]

@johnsonshiue your comment was a great idea to make an "offset" surface, however, I cannot then select the surface feature as the second transitional selection...it seems like it only wants me to select one face, not a surface.

The tooltips that pop up for Selection #1 is "Moving Face" and for #2 is "Transitional Face"...see also https://help.autodesk.com/view/INVNTOR/2019/ENU/?guid=GUID-EDE88086-58F3-4F62-A1CC-83CDB035BC27

Does is matter that the part I put the surface offset is a multibody and is also in a subassembly?

[JDMather]

@SER4 Attach your assembly here.

[johnsonshiue]

Hi! Like JD mentioned here, please share the example files. There could be an issue with the geometry. We can help take a look and propose the good workflow.

Many thanks!