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

----- Original Message -----
From: Raymond Heckert <jnr@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Tuesday, October 29, 2002 11:18 PM
Subject: 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
>
> ----------
> > 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?
>
>
> Addresses:
> FAQ: http://www.ktmarketing.com/faq.html
> FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/
> Post Messages: CAD_CAM_EDM_DRO@yahoogroups.com
>
> Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
> Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
> List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@...
> Moderator: jmelson@... timg@... [Moderator]
> URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
>
> OFF Topic POSTS: General Machining
> If you wish to post on unlimited OT subjects goto:
aol://5863:126/rec.crafts.metalworking or go thru Google.com to reach it if
you have trouble.
> http://www.metalworking.com/news_servers.html
>
> http://groups.yahoo.com/group/jobshophomeshop I consider this to be a
sister site to the CCED group, as many of the same members are there, for OT
subjects, that are not allowed on the CCED list.
>
> NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY POSTING THEM.
DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO EXCEPTIONS........
> bill
> List Mom
> List Owner
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>