Re: [CAD_CAM_EDM_DRO] Re: DRO encoders- Rotary or Linear?

Alex, It's not merely a backlash issue. (Although, a
properly designed roller chain transmission *must* have
some slack built in. As any kind of roller chain meets the
sprocket, and changes from linear to rotary motion, the
chain jumps up, and down at each pitch. This is more
pronounced with low tooth numbers, and double pitch chain.
Immediately, upon full engagement with the tooth, the
linear section of the chain begins to swing downward, as
the disappearing tooth 's rotary motion moves it downward.
When the next tooth engages, the chain is brought up to
tangency with the pitch circle again. This is only minute
movement, but it sets up a quite a vibration. Timing chain
is about the only chain that doesn't exhibit this quirk,
which is why they're called timing chains, because that's
what they're used for. Virtually vibration free, and they
take up their own slack by climbing to the highest
available form on the tooth.

RayHex

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> From: alex <telecomt@...>
>
> This may be a stupid question, but why not to use a

normal bicycle

> chain\sprocket combination for driving an encoder?
> Is it a backlash issue?