Chain..... How you do it properly?

[JasJ002]

Ok this has been bugging people on our team for a couple years and I haven't been able to find anybody else who knows how to do it propely. Anybody know how to do chain properly so that when the gears move the chain moves as well. Just looking for idea's, I figure if we all network idea's together we could all accomplish this quicker.

[Daniel_H]

I don't know how to make it perfectly as you described but we could make a research group to find it out heuhehue.
I just knew about the "chainer" a few posts ago...

[Jeff Rodriguez]

Try Dr. Joe's Chain Path Visualizer
http://www.chiefdelphi.com/forums/sh...threadid=32174

[Tytus Gerrish]

im not shure weather your talking about gear reduction or active chain tensioners could you please clairfiy what your doing and what you need help with

[Daniel Brim]

Originally Posted by Ogre

Try Dr. Joe's Chain Path Visualizer
http://www.chiefdelphi.com/forums/sh...threadid=32174

Does that work for actually making chains in Inventor? The only screenshot I see is from JVN, and it just looks like a 2D CAD thing.

[RogerR]

Originally Posted by Tytus Gerrish

im not shure weather your talking about gear reduction or active chain tensioners could you please clairfiy what your doing and what you need help with

i assume that hes talking about making chain in inventor, since this is in the CAD section.

[jdiwnab]

I tried to make chain that would move right using some already made chain (came in 2 parts that had to be contrained together repeatidly). While I could get the chain to stay together on it's own, it would break once I tried to constrain it to a gear. Because of the way gears are made (not just in and out, I think it is called involute) there is no "center" in the gaps to place the chain, only possible centers (there's about 3 "center" points to constrain to). My chain was either slack, broke (how does Inventor do that?), or Inventor was yelling at me for breaking it. Therefore, the most obvious route doesn't work.

[JasJ002]

I'm not talking about chainer, I'm talking about how to constrain it straight to the gear.

[Elgin Clock]

I'm not to familiar with Inventor, so take this with a grain of salt.

I work with SolidWorks for 3D CAD mainly.
I would assume that you can mate the chain somehow to the center of the gear to cetralize it in the grooves so it has no sideways off the gear movement, and then mate some part of the chain to the center of the arcs in the gear's Internal Diameter..

I'm not sure if the CAD software would be smart enough to release the mate to the chain and the gear's arc as you rotated the chain through it's path.

I know the version of Solidworks (2001) a few classmates and myself tried to use to make a geneva wheel we couldn't get the mechanism to work correctly, but we did have some sucess.


In essence, you need a temporary mate to a link and gear when it is in contact, and for that mate to release itself when the chain leaves the gear.

constraints = mates btw.
SolidWorks calls 3D constrainst between assemblies Mates, and constraints between lines in sketches constraints. Sorry if there is any confusion due to my wording.

edit: another cool geneva wheel animation:
http://www.brockeng.com/mechanism/Geneva.htm

More cool mechanisms:
http://www.brockeng.com/mechanism/index.htm

[petek]

This movie shows as far as I got with this problem. The links are actually constrained tangent to a hidden chain path (like J's famous "chainer"). It would lock up with more links and also when the three links got to the end of the straight path and tried to transition to the curve on the left end.

The links are actually "pulled" by a hidden block which is constrained to the path and is moved by the animator dial. Without the chain links holding it up, it would follow the whole path around.

This was done in Inventor 6 a couple of years ago, btw.

[Daniel_H]

I'm having some problems to dimension my "chainer", my last link always has to be smaller or larger to fit the chain exactly.
Is there any pack of formulas to do it?

*I'm using different sized sprockets

thanks in advance

[Madison]

Originally Posted by Elgin Clock

I know the version of Solidworks (2001) a few classmates and myself tried to use to make a geneva wheel we couldn't get the mechanism to work correctly, but we did have some sucess.

I am not familiar with Solidworks software older than 2002 version, so is it safe to assume that Solidworks 2001 does not provide the option to model physical interference during movement? In 2002 and newer, at the very least, you can model the interference of physical parts against one another and that should serve to make a geneva mechanism work.

[Matt Krass]

Originally Posted by M. Krass

I am not familiar with Solidworks software older than 2002 version, so is it safe to assume that Solidworks 2001 does not provide the option to model physical interference during movement? In 2002 and newer, at the very least, you can model the interference of physical parts against one another and that should serve to make a geneva mechanism work.

M, if you want to be a nice sister and send me the requisite CAD models, I'll test it out on 2005 Office Pro for you.