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gyro17-air1.jpg
gyro17-air2.jpg
gyro17-dc.jpg

DESCRIPTION:

These are pictures of gyroscopes.

Posted by James Waldby <j-waldby@pat7.com>.  

The following description was provided:

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http://www.metalworking.com/dropbox/gyro17-air1.jpg 60203 bytes
http://www.metalworking.com/dropbox/gyro17-air2.jpg 75991
http://www.metalworking.com/dropbox/gyro17-dc.jpg   60150

Three pictures of gyroscopes, re the thread "Gyro" in  
rec.crafts.metalworking, 17 Jul 2002, in which 
Don Nichols mentioned two kinds ...

>         Well ... I have seen two ways in various vintages of aircraft
> gyro instruments (both in the actual instruments.)
> 
> 1)      Really old.  the flywheel has a bunch of scoops cut in the rim
>         and is driven by a tangential jet of air.  (Good bearings are
>         needed, of course.)
> 
> 2)      Old enough to show up in surplus about 1960 or so.  The
>         flywheel is implemented as an inverted induction motor rotor
>         driven by a 26V 400 Hz three-phase stator mounted inside it.
>         (Again, the bearings have to be pretty good.)
> 
>         The second one was for an artificial horizon,
....

The picture gyro17-air1.jpg shows the first kind he mentions.  Air
intake holes are visible around cylinder at right edge of picture.
The brass wheel spins on bearings supported by a gimbal frame.  The
air drive nozzle is on a fixed arm that projects inside the gimbal
frame, at the right side of the wheel in picture gyro17-air2.jpg.  The
small circle at the end of the arm is one end of an adjustment screw
for centering the nozzle block connected to the copper air pipe.

Picture gyro17-dc.jpg shows a gyro driven by a small DC motor.  The
motor label shows Delco and GE part numbers and says 27.5 D.C. 10000
RPM.  The spinning portion of this gyro is the brass disk at the front
of the picture; all the rest is frame, motor, gimbal, and contacts.

-James Waldby