"cosmetic" roller chain -- how to?

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greets all.. got a little 'dohickey' i'm drawing that consists of sprockets and chains (and associated motors and shafts)...

i would like to "show" the chain.. but i dont want to model it as a component. (nor have to draw it link by link)

i'm looking to add sort of a volumetric "place holder".. that tells me "this is where the chain is"

anyway to really do that? do i sketch a cross section of chain (rectangle) and sweep it along the chain path, over the sprockets? will i be able to mate that?

it'd be great to actually have the chain "hang" on the sprockets.. and see the slack when i change the sprockets distances. but i'm guess'n i'm asking for a little too much there.

thanks again you folks have been a great help,

-tony

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spoke to soon.. a "rope" would be the answer to my problem. one flexible body. pipedreams?

-tony

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You can do this by creating the chain in context within the assembly. I'd draw the path of the chain and then sweep a rectangle to create a flat belt looking dohickey. You can set your total length of the chain using equations. Draw the top of the joint with a straight line, around the sprockets with circular arcs, and the droopy bottom with a circular arc snapped tangent to the sprockets. You can dimension the length of an arc by clicking it's endpoints and then the arc itself. Do this for the three arcs and the line and set their sum equal in an equation. That way you have fixed the overall chain length and the sag (radius of the bottom arc) will be free to adjust.

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pure genius, thanks! going to try it right now. didnt think of adding arc-length to the equation.

much appreciated,

-tony

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I did not know that, that is so handy!

Dan Bovinich

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OK gang! I require roller chain, but used for lifting. We make vertical conveyors (freight elevators people can't ride). One end is connected to a platform and the other end basically droops over the sprocket (it's actually connected to a piece of #35 chain and back to the platform). It would be nice to show the chain lengths at different heights of the platform. I may be answering my own question, would I just have two equations which calculate both sides of the chain? No way to simulate the movement of the chain via the sprocket rotation?

Keith see

for examples.

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I can think of ways to simulate the chain and sprocket movements, but it will require a lot of work. Using a variation of Mike Wilson's slot cars, you've have to mate each link by hand. There was a 3rd party app to model chains a few years ago, but I've lost sight of it. The sprocket rotation would be done with a gear mate, working like a rack and pinion gear.

It would be a lot of work, and rebuilds would probably take forever. It might be interesting to explore though.

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I forgot to say that I think you're right that you're probably stuck with equation-driven patterns, for a practical assembly

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Another thought: If the chain is spec'd by the foot, you might want to fake the chain with a curve-driven pattern in a part. The links might not look like links up close, but you could make it look ok.

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what about 'assembly layout sketch' see SW help for an example

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What I usually do is manually position the elevator car (or with a config) and then rebuild to have an equation vary the lengths of the chain on either side of the top sprocket. Then this also properly positions the counterweight on the back side per the established chain length. Let me know if you want an example. One equation & rebuild sets the chain legs, and the next rebuild sets the counterweight height to the reconfigured chain end.

WT

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