Flywheel/Encoder patterns

[Chris Morriss]

In message <9612070732.aa08727 at device.data.co.za>, Kalle Pihlajasaari
<kalle at device.data.co.za> writes

[Deleted]
>
>
>I was thinking for 'no-brainer' retro applications one could just add
>a viscous brake to te shaft so after the first 20 degrees the units would
>then be at the extreme limit of the backlash.
>
>Problem is extra wear on components from the drag and getting something
>that will work at all engine speeds, perhaps something electromagnetic
>like a Tacho generator (plug it into your Tacho display also)
>
>You would have to go with multiple coils to keep things simple but
>might be able to keep the old dizzy in the boot (trunk).  Getting
>this to work with the fuel system would take some doing but if
>you make your own into the existing harness you could swap the old
>unit back again using the old 35 tooth sensor if you get stuck in
>vancouver or something.
>
>Cheers     *<<<-|

A neat and very reliable solution to taking up the backlash is to mount
an eddy current brake on the shaft.  Much easier than providing viscous
drag.  All you need is a plain aluminium or copper disk rotating in the
gap of a horse-shoe magnet.  Like a old electricity meter. (If you had
the rotating disk meters in the US)  The principle was also used as the
speed control a#on the old but revered Garrard 401 record turntable.

Bye,
-- 
Chris Morriss