using assembly constraints

[pkoepf]

how do I create a cam and follower relationship, such that when I turn the cam, the follower will remain tangent to the surface of the cam

 

[mmauldin]

You can use the "touch" constraint. For the follower to follow the cam, the cam face must be a single surface. In the attached example the cam face was created by extruding a curve created by joining the curves of the sketch into one continuous curve.

Open the attached assembly and rotate the cam. Note that as you transition from the "round" part of the cam to the "flat" it hesitates but will eventually solved and continue. Probably a lot of math going on there.

 

[JohnRBaker]

As an alternative, if you don't want to go back and create/recreate the Cam profile over again, go to...

Insert -> Combine -> Join Face...

...and select the 'Convert to B-Surface' option, select faces that define the 'face' of the Cam and then hit OK.

In the end, I think this results in a cleaner model (certainly one with less features since you can use an internal sketch to create the Cam).

To see an example of this approach, open the attached Assembly, and once opened, to see the Assembly 'perform', go to...

Assemblies -> Sequence...

...and Play the Sequence (hit the VCR like 'Play' button).

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

UG/NX Museum:

http://www.plmworld.org/p/cm/ld/fid=209

To an Engineer, the glass is twice as big as it needs to be.

 

[eex23]

As for me, Johns cam assembly does not seem to be working: follower rotates with cam (not up and down as it should be)

 

[JohnRBaker]

I tested this by opening the assembly in the zip file into a totally different version of NX and when I played the Sequence it worked just fine.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

UG/NX Museum:

http://www.plmworld.org/p/cm/ld/fid=209

To an Engineer, the glass is twice as big as it needs to be.