We need a resolution in Creo Parametric 8.0 for a chain assembly.
We want to assemble a chain in a curve using a curve pattern. But the pitch distance is not equal in the straight line and in the curved path. It is the same along a straight line and varies along curved paths. This is critical assembly and so we should assemble the chain as exactly as they are in real assembly. How to assemble a chain in a curve using a curve pattern without changing the pitch value?
1) There may be a lot of ways to assemble the chain links in a curve. But chain assembly is used universally and so there will be a simple solution to do this (For instance, pattern). So, we want to assemble the chain links using "pattern" along the curve or else a very simple method to do this. Because for a long chain assembly we could not assemble multiple times or go for a lengthy process.
2) There is a way to do this using "pattern". While we search on the internet in all places this method is used. But the problem is the chain links will not assemble in the exact place as the pitch value varies along the curve. But as the assembly is critical we need to assemble the chain exactly in the same place as they will assemble in real life.
Our trial and difficulties:
We have tried to pattern this using eight patterns.First and second are for top straight line pattern two times for inner links and outer links. 3rd and 4th are for curve patterns. 5th to 8th are mirror patterns.
1) If we change the no of links, the pattern will fail and we need more time to correct them and reassemble the links.
2) If we change the no of links, sometimes the link position will change (the same link comes nearby at the pattern ends) so that we have to reassemble the links once again.
3) Creo Parametric does pattern using number id. For instance, if we do a pattern first time, the number will be 1 to 10. For the second pattern, the number will be 11 to 20. We have connected the "no 10" link to the "no 11" link. When we change the number of links for the first pattern as 1 to 5 and for the second pattern as 6 to 10. The pattern will fail and creo will not change the assembly reference from 10 - 11 to 5 - 6. This is the major problem in Creo which should be fixed or we need to know the solution if any one is there. Because this not only affects the chain pattern but also all other patterns like sprocket teeth pattern, gear teeth pattern, toothed belt pattern,etc.
4) If we try to assemble other complex curve shapes (using more idler sprockets) this will be very difficult to assemble.
5) Sometimes if the no of teeth on sprocket changes, the last link on sprocket (curve) will not meet at the straight line end it has to be assembled a little inside from the straight line. This is very difficult to assemble using more steps and more patterns. (My given curve to you is like this). We have achieved this using relations. But if we change the no. of teeth this will also fail. We do not have enough time to program this.
6) Finally, if there is an option to pattern along the curve using equally spaced displacement (not distance along the curve) between points, all this problem can be fixed easily. Using programs it is possible to develop such an option. So, kindly add this pattern option in the curve pattern tools.
We also found an udf chain assembly curve and that also was not properly assembled. They only look like a proper chain assembly.
Also, we need to assemble cam roller on cylindrical groove cam using pattern on curve and also creating tooth on curved belts.
Kindly implement a pattern tool to pattern along a curve with equal displacement.(Not distance along curve which is now available)