[time-nuts] Odd request

[Normand Martel]

...And i forgot one thing...

The Telechron solenoid assembly is symmetric and
reversible.

That allowed some manufacturers to sell "Bar clocks"
that had their hands run backwards!!

73 de Normnad VE2UM

--- Normand Martel <martelno at yahoo.com> wrote:

> Hi Tom...
> 
> Not only Telechron were very popular electric clock
> movements, they were BY FAR  the very best
> mechanical
> movements ever made.
> 
> When young, i've opened A LOT of used
> electro-mechanical clock movements, and most of them
> showed evident traces of wear. Worn-out gear
> pinions,
> dried-out and seized brass/steel bushings, dried-out
> and cracked nylon pinions (Nylon tends to harden and
> shrink with time and heat, so Nylon parts shall
> NEVER
> be put on a traction stress when manufactured) were
> frequent on old clock movements, but NEVER on
> Telechrons, except very
> rare cases of pinion wear on the output shaft (3.6
> RPM)
> 
> Telechron movements were very unique. The motors
> were
> two-pole shaded pole synchronous motors with an
> external solenoid and a completly sealed rotor
> stuck within the poles pieces. The self-starting
> rotor, composed of three spring steel disks forced
> in
> place on a smooth shaft and spinning at 3600 RPM (60
> Hz) was inside a sealed cylindrical aluminum gearbox
> (older gearboxes were in a copper sealed box)
> containing not only the rotor shaft, but also a
> 1000:1
> reduction geartrain. Pinions were made of stacked
> thin
> steel pinion disks forced on the shaft to form
> single
> solid pinions. The faster rotating gears plates were
> made of some kind of red-orange colored fiber
> material
> and the slower rotating (higher torque) plates, of
> soft brass. The gear holding plates were made of
> thick
> alunimum with a thinner aluminum subplate that
> prevented the gears from sliding longitudinally, but
> far more important, the thin space between the
> plates
> and subplates had a capital role: Keeping a fine
> capillary oil film between the plate and subplate,
> that film kept the gear shafts permanently
> lubricated,
> thus eliminating all trace of wear. Even the gears
> themselves (the rotor was spinning at 3600 RPM and
> the
> second gear, at 864 RPM) didn't show any trace of
> wear, even under a magnifying glass.
> 
> I even remember the gear ratios of a Telechron:
> 
> Rotor: 12 toothed pinion (3600 RPM)
> Second gear: 50 tooth fiber plate coupled to a 12
> tooth pinion R:r: 4.1666667:1
>  Third gear: 54 tooth fiber plate coupled to a 18
> tooth pinion R:r: 4.5:1
> Fourth gear: 60 tooth fiber plate coupled to a 12
> tooth pinion R:r: 3.3333333:1
>  Fifth gear: 60 tooth brass plate coupled to a 12
> tooth pinion R:r: 4:1
> Output gear: 60 tooth brass plate coupled to an
> external 10 tooth pinion R:r: 4:1
> 
> 4.16667*4.5*3.333333*4*4=1000
> 
> Definitely a fine movement! I still use an oooold
> Telechron at my shop.
> 
> 73 de Normand VE2UM
> 
> --- "Tom Van Baak (mobile)" <tvb at LeapSecond.com>
> wrote:
> 
> > 
> > See Mitchell's SWCC page at:
> > http://www.telechron.com/
> > 
> > /tvb
> > 
> > 
> > _______________________________________________
> > time-nuts mailing list
> > time-nuts at febo.com
> >
>
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> > 
> 
> 
> 
> 
>  
>
____________________________________________________________________________________
> Need Mail bonding?
> Go to the Yahoo! Mail Q&A for great tips from Yahoo!
> Answers users.
>
http://answers.yahoo.com/dir/?link=list&sid=396546091
> 
> _______________________________________________
> time-nuts mailing list
> time-nuts at febo.com
>
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> 



 
____________________________________________________________________________________
Get your own web address.  
Have a HUGE year through Yahoo! Small Business.
http://smallbusiness.yahoo.com/domains/?p=BESTDEAL