Re: Microwave Oven Sync. Motors!

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jim Mitchell" <Electrontube-at-sbcglobal-dot-net> 

But wait Terrry,  If you remove the gears it spins quite fast,  perhaps 400
RPM.  And it has plenty of power to swing a W rod!

Regards - Jim Mitchell
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Saturday, April 17, 2004 10:29 AM
Subject: Re: Microwave Oven Sync. Motors!


 > Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>
 >
 > Hi Jim,
 >
 > Many small AC gear motors (like clocks use) are synchronous.  Digikey
sells
 > these raw motors too.  The problem is they are too slow with the gear
works
 > and too low of power to do much with.  Since they are very low power
 > impedance protected things, they don't have to worry about overheating or
 > efficiency which is terrible in them from a percentage point of view.  We
 > need to be able to turn big rotors fast so we need bigger motors.  I think
 > John Freau say we need at least 1/10HP.  1/4HP 1800 RPM is perfect IMHO.
 >
 > Cheers,
 >
 >          Terry
 >
 > At 06:58 PM 4/16/2004, you wrote:
 > >
 > >
 > >One more thing... I assume they use synchronous motors because they will
 > >turn the other direction if stopped.  That way the turn table would spin
 > >the other way if it got obstructed.  Another thing I found synchronous
 > >motors in are those plastic "Disco Balls" that you see from time to time
 > >in novelty stores.
 > >
 > >Regards - Jim Mitchell
 > >----- Original Message -----
 > >From: <mailto:Electrontube-at-sbcglobal-dot-net>Jim Mitchell
 > >To: <mailto:tesla-at-pupman-dot-com>Tesla list
 > >Sent: Friday, April 16, 2004 8:57 PM
 > >Subject: Microwave Oven Sync. Motors!
 > >
 > >Hello List,
 > >
 > >This may have been discussesd before but...
 > >
 > >I was taking apart a brand new "Galanz" brand 700w microwave (payed 40$
 > >for it ;-))  And I was removing the turn table motor when I noticed it
 > >said SYNCHRONOUS MOTOR on it.  So I plugged it in,  and it spun slowly,
 > >like 5 RPM.  I popped the case open and removed the gear assembly... I
 > >then turned the motor on again.  This time It was spinning faster ~400
 > >RPM?  It was also in sync with the line as the stick I had put on the
 > >rotor was standing still in 5 different places.  The motor just had a
coil
 > >surrounding a rotor made of what seemed to be a magnet.  I doubt this
 > >would have a lot of power but may work for a small propeller gap.  Sadly
 > >mine stopped working after I got metal shavings stuck to the rotor and it
 > >froze up.
 > >
 > >Regards - Jim Mitchell
 >