Re: To David Soderman: A Little Test

["Ernst Dinkla" <E.Dinkla@xxxxxxxxx>]

----- Original Message -----
From: "Kennedy McEwen" <rkm@kennedym.demon.co.uk>
To: <scan@leben.com>
Sent: Friday, April 12, 2002 8:10 PM
Subject: Re: To David Soderman: A Little Test


> In article <000701c1e1ff$7e082e60$0100a8c0@KAIROS>, Ernst
Dinkla
> <E.Dinkla@chello.nl> writes
>
> >The carrier is inserted in a traction unit that positions the
> >carrier for scanning etc with the gear teeth at the side of
the
> >carrier. For scanning the whole traction unit glides on two
rods
> >with a traditional 3 point brass bearing setup. That movement
is
> >done with a finely machined screw spindle (don't know the
right
> >English term for it).
>
> A "worm drive"?
>
> That is frequently used when relatively large rotational
motion, such as
> from a motor, need to be converted into fine linear movement.
A
> derivative is the "worm gear", used to achieve very low
precision
> gearing ratios, where the driven linear unit is replaced with a
> concavely curved toothed wheel.

Worm wiel en worm schroef are the Dutch equivalents. But that
translates to Worm wheel and worm screw. It should be the last
but then it usually is a shorter piece. So worm drive may be more
appropriate for a 12 cm long 8 mm thick object. The stepmotor is
driving it directly with a crosscoupling crossaxle? :-) in
between.

Kennedy, what kind of glass could I use for a film carrier ?
Some companies that sell optical glass sell quality picked float
glass, nothing special in fact. Up to 1.1 mm the thickness
variation is within 0.05 mm. On a piece of 300 x 115 mm it will
be less than that. The Nikon carrier + scanner would allow  up to
1.5 mm thick glass maybe 2 mm but nothing above that.

Ernst





-
Turn off HTML mail features. Keep quoted material short. Use accurate
subject lines. http://www.leben.com/lists for list instructions.