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Double Balance wheel WTF!


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I hope this is the right place to post this question?

But how does this even work ..is it just there for show? it's hard to tell from the photo's but looks like there is no escape wheel on the right balance but there is one under the left balance?

http://www.good-stuffs.com/Shanghai-Diamond-double-skeleton-flying-wheels-automatic-watch_p_296.html

Edited by SteveT
typo
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If you look closely, there is an escape wheel driving the right hand balance wheel.  The top jewel for it is below and to the right of the wheel just showing under the dial.  It's very much a cheap gimmick!

 

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Not sure if this particular application of dual oscillators is simply cosmetic or if it is actually properly designed to take advantage of resonance, a phenomenon which is used in multiple oscillator time pieces to improve the stability (and therefore the accuracy) of the oscillating system. Multi-pendulum clocks have been around for a while, have a read of this;

doublependulumclocks.pdf

The oscillators don't have to be pendulums though, balance wheels do the same thing and the principal has been used in some pretty high end watches;

http://www.luxuo.com/style/watches/why-two-balance-springs-are-better-than-one.html

So in theory there is a potential advantage to be had by using two balances in a wrist watch. In practice though I wonder if the trade off between additional friction within the system (resulting from more wheels, pivots, etc) and the improved stability actually results in any discernable benefit, especially in a movement which has been mass produced down to a price rather that precision engineered to the highest standards. I don't doubt that the use of multiple oscillators in high end movements which are made to the finest tolerances can be shown to impart some benefit. However, in the watch in @SteveT's  post I suspect that variation in the fit of all of the individual components due to the manufacturing tolerances more than wipes out any possible improvement, making this, as @Geoso succinctly puts it "a cheap gimmick!"

It is however an interesting principal.

I would love to see someone try and put together a 4 balance system using cylindrical hair springs, each mounted in a 3 axis tourbillon, just for the sheer overkill of it!!

Edited by Marc
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