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Unread 19-12-2010, 18:36
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Re: Sprockets as Chain Tensioners?

Quote:
Originally Posted by Chris is me View Post
I've been interested in making a simple test bed for something like this but I have no idea what I should be measuring - I assume current draw?

Personally I'm going to wager a guess that friction in tensioners is essentially negligible. Shaker just uses blocks of Delrin or nylon pushing against the chain (not spinning) and we have no problems at all. We even had a multi-purpose Delrin rod we used as both a tensioner and as a structural member (standoff)
I doubt that a static tensioner has a negligible effect on efficiency.

If you've got a two stage spur gear reduction and a single chain run from the gearbox you're already down to 83% efficiency or so. If you then shove a block of plastic into the chain to tension it, it would seem you would be liable to lower efficiency quite a bit.

We have no data, but empirical evidence has suggested to us that our overall drivetrain design is noticeably more efficient than the average drive similar to ours in terms of same number and type of motors, similar gear reductions, top speeds, and wheel type/friction.
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