Alt-BEAM Archive
Message #01832
To: beam@corp.sgi.com (mailing list)
From: Benjamin Edward Hitchcock beh01@uow.edu.au
Date: Mon, 29 Mar 1999 13:42:09 +1000 (EST)
Subject: [alt-beam] Re: Small parts
----- Forwarded message from Robert McIntosh -----
>
> Excellent description of the gear boxes (deleted). However this ratio
> may need correction. For an AC motor, the synchronous speed can be
> calculated by the equation:
>
> (120 x f)/P
>
> Where f is the frequency of supply and P is the number of poles. So for a
> motor with 2 poles operating with a 60 Hz supply, 3600 RPM is correct.
> However, usually the motors used in these timers have many more poles(may
> be 20 ?) so they run quite slow. Depending on the number of poles on the
> motor, the gear train may have a ratio of 20,000 (more or less).
> Dilip
Does that formula change with voltage?
Why can't we rewind a small motor to get what we want? I gather it is to do
with the gauge of the wire and the number of turns. The radio controlled
car fanatics rewind their motors to get more torque so.....? The Maxon
motors have the coils moving around the magnets so
Rob
------------------------------------------------------------------------
eGroups Spotlight:
"Kosovo-Reports" - Direct reports from Kosovo/Serbia/Yugoslavia.
http://offers.egroups.com/click/252/0
eGroup home: http://www.eGroups.com/list/alt-beam
Free Web-based e-mail groups by eGroups.com
----- End of forwarded message from Robert McIntosh -----
--
Nothing is foolproof to a sufficiently talented fool.
------------------------------------------------------------------------
eGroup home: http://www.eGroups.com/list/alt-beam
Free Web-based e-mail groups by eGroups.com
Home