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Ever-hanging part in assembly

mwetter

New member
I am looking for a way to have a "flexible" part in an assembly.
I have posted once on this before but I will try and explain a little
more in detail this time since I only got one answer with my last post.



Imagine a bellows between a set of hinged plates - the bellows need to
expand and contract as the the two plates go apart or come
together. This is what I need to try and accomplish.



We design after market air suspensions and we do a lot of drawings for
custmers where we need to show the suspension at a certain height - to
this point we have been transferring our assembliues to a 2D cad and
manually inserting an air bag that looks correct. We would love
to be able to move the suspension in mechanism and have the air bag
update to the different positions.



Help!
 
I would suggest writing some simple relations to govern the shape of the air bag.


If the space between plates is, for example, 12", you could write a relation that makes the sketch of the air bag "100%" inflated. Then, if the space decreases to 6", that same relation would decrease the air bag sketch to "50%" inflated.


I don't know if you can accomplish what you want using Mechanism Design Extension, I'm just not familiar enough with MDX. But it shouldn't be too hard to sketch a base feature of the air bag, and tie it to the plate separation distance with a relation.
 
Think about the planes that would coincide with the intersections of the "flexible" surfaces of the " bag" on the bellows. Use relations to maintain equal angles between those planes, the other end of which are intersecting a shared axis. Use the Mechanism connections, then you can MDO to provide the motion and animation to record the motion you want to illustrate.
smiley4.gif
 
flexible component would work too. And you could use a relation.
Might try Warp. You use warp to modify the part and
control the size using a family table that turns that feature on or
off.
 
I was just playing around with the WARP feature a couple of days ago. That is a good suggestion.


It is very easy to use. I had it all figured out the first time I used it, just by playing around with it.


Give that a try.
 
I sat up for four hours one friday night trying to figure out a place
for warp on a production model. Proving form, flexible
components... It is a different way of modeling for
sure.
 
The only use I've found for the WARP feaure, in production models, is for stickers and lables.


Oursticker and label drawings are shown flat, as they are manufactured. Some labels are put on cylindrical parts, thus the models need to follow contour. It is very easy to "bend" a flat sticker model onto a round contour using the BEND command of the WARP feature.


It works really well.
 
But what about those contour parts with compound surfaces? I
think the warp tool needs a hot blower tool to get the sticker bubles
out.



More humor.. it's early and I have not had my coffee yet.





Rhino has a simular tool and I saw a past student create a shoe insole
with warp. I have not been able to get the same results in Pro/E
warp.
 

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