The Duometre works with two barrels thanks to one key component that's visible on the dial - the foudroyante

Oct 04, 2019,10:21 AM
 

One barrel powers the timekeeping train, just like any watch. But at the same time, there is an extra "escape wheel" of sorts, stacked on top of the regular escape wheel. This extra escape wheel regulates the power of a second geartrain (which powers the chronograph), through a six-pronged star wheel. 


Thus by this mechanism, power is effectively isolated between the timekeeping train and the chronograph/complication train. There are some parallels of how it works compared to a star and flirt of a deadbeat or a foudroyante, in a way. 




Among the three regular Duometres (excluding the tourbillon variants), the best use of the double barrels is the chronograph, because the chronograph is a complication that requires a sudden spike of power on the user's demand.

When the chronograph is stopped, a lever blocks the star wheel so that the teeth of the star wheel are moved out of the way of the second escape wheel, thus they are disconnected. This is at the 0s mark of the foudroyante dial.



When the chronograph is started, the lever is released, and the power of the chronograph mainspring barrel drives it forward until it engages the teeth of the second escapement. 

In the video below, you will notice the foudroyante hand jump to the nearest half between the 1/6th numbered markings of the dial, rather than on the numbers themselves. This is because the half markings are when the star wheel engages the second escapement, while anything in between are the "dead zones" where the chronograph is disconnected from the second escape wheel. By having the lever stop the star wheel right on the dead zone at 0, the chronograph is effectively stopped and isolated.


Images labelled and cropped from bexsonn.com 

Regards, 
skyeriding


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Duometre rattrapante chronograph

 
 By: cory : September 21st, 2019-21:00
So I know I’m not the only one here waiting for the next Duometre creation. What I would love is a really new and innovative rattrapante chronograph housed in a new tantalum case design. What would you like to see?

That. Exactly that. [nt]

 
 By: amanico : September 21st, 2019-21:33

+1...I am all in [nt]

 
 By: holdemchamp1225 : September 22nd, 2019-05:25

+1

 
 By: Pour le Mérite : September 24th, 2019-09:29
40 mm of diameter, please!

Do so. But most important...

 
 By: Pour le Mérite : September 24th, 2019-09:47
... competitive pricing at $40,0000 so I can actually buy it.

:))) [nt]

 
 By: amanico : September 24th, 2019-09:56

Two drums

 
 By: Jurry : September 21st, 2019-22:19
You’ve got to help me here. If I’m not mistaken one of the unique (nowadays maybe not so unique anymore) features f the Duometre is that it has 2 drums. One supplying continuous power to the time keeping part, the other one to drive whichever application ... 

Thanks

 
 By: Jurry : September 21st, 2019-22:31
In which case my order of the day will be Duometre Platinum case Perpetual Calendar Chronograph

Very busy

 
 By: Jurry : September 21st, 2019-23:23
It will be very busy which creates a challenge for the watchmakers and designers to cramp it all in and still retain clear legibility haha No I’m joking and I agree: it might be to busy on the dial. I should leave such ideas to those with more design expe... 

The Duometre works with two barrels thanks to one key component that's visible on the dial - the foudroyante

 
 By: skyeriding : October 4th, 2019-10:21
One barrel powers the timekeeping train, just like any watch. But at the same time, there is an extra "escape wheel" of sorts, stacked on top of the regular escape wheel. This extra escape wheel regulates the power of a second geartrain (which powers the ...  

Indeed.

 
 By: Brego : September 21st, 2019-22:59
I’ve asked myself why JLC being such a historically important watchmaker, don’t have a proper split seconds chronograph. I’d love to see them try it. And if it’s in the same 40,5 size as the Quantirmr Lunaire Email, even better.

A completely new Duometre design though of course...

 
 By: cory : September 23rd, 2019-01:16
what will they bring us?

Well that was easy. [nt]

 
 By: cory : September 22nd, 2019-02:23

Indeed! [nt]

 
 By: amanico : September 24th, 2019-05:43

If this materialize

 
 By: benlee338 : September 24th, 2019-16:35
It will be a killer watch. Duometre is hands down my favourite line in JLC and having a split second complication will be very cool. But I am not sure. Not too long ago, I heard rumours that the Duometre might be dropped completely by JLC due to poor sale... 

You know, an Annual Calendar...

 
 By: watchme : September 25th, 2019-08:22
has yet to be presented, and if the bottom subdial could be a photo-realistic moon, this could be very interesting and give JLC another nice alternative, in addition to the QL, to the 5146R (which, I personally think it blows away - from dial layout to mo... 

Dream Duometre

 
 By: RGS : September 25th, 2019-10:12
40,5mm case, platinum, silver dial, I guess around 70K for this JLC and the best split second chronograph out there! Maybe also a rose gold, white/cream dial and white gold, black dial for around 50-60K? Count me in! Cheers!

I would guess 70K at least! [nt]

 
 By: cory : September 25th, 2019-10:46
No message body

Only just! 😂

 
 By: cory : September 25th, 2019-11:15
I still think if and when this piece comes it will be in excess of 100k.

True!

 
 By: RGS : September 25th, 2019-12:10
The Quantieme Lunaire is at 40K and the Chronograph at 45K? So a split second Duometre sounds good at the 60K -70K range. The ALS double split is around 100K I think. But, apart from all this, it would be simply spectacular! Come on JLC...

+1 [nt]

 
 By: cory : September 25th, 2019-14:02

You know I like dreaming.... ie something spectacular and expensive! [nt]

 
 By: cory : September 25th, 2019-14:04
I just want JLCs equivalent of the Triple Split!?

JLC vs ALS ;) [nt]

 
 By: cory : September 25th, 2019-14:16
For the best chronograph in the industry.

I want JLC to take the TOP.

 
 By: cory : September 25th, 2019-14:20
No message body

True.

 
 By: cory : September 25th, 2019-14:33
I actually think they are focusing on high complication at the moment and we will see others soon.

I am excited to see where JLC take the Duometre Spherotourbillon next also. [nt]

 
 By: cory : September 25th, 2019-15:03
I am still a sucker for tourbillons!

I agree with you here regarding the Gyros.

 
 By: cory : September 25th, 2019-23:23
I must do some more reading up on the Gyro 5 as I’m yet to discover it for its true beauty.

Dreams of a Rattrapante with symmetry pushers.

 
 By: cory : September 30th, 2019-00:01
I have requested this over a year ago but I will request it again. A few JLC tricks. I would like to see this Duometre Rattrapante take on a more high complication design than mid level. Sorry Nico.

Call your bank ;)

 
 By: cory : September 30th, 2019-01:56
They are there to help. 😂

I wonder what other technical Duometre creations JLC will surprise us with!?

 
 By: cory : October 3rd, 2019-16:07
I'm really hoping to see some new technical marvels come into the Duometre family. It has been way to long!

Hmmmm who knows! [nt]

 
 By: amanico : October 3rd, 2019-16:33

I hope they bring some serious new innovative and techincal pieces. [nt]

 
 By: cory : October 3rd, 2019-16:50
I would also love to see some high complication Duometres. New mechanisms!!

Same here. [nt]

 
 By: amanico : October 3rd, 2019-22:51

New mechanisms aye! 🙏 [nt]

 
 By: cory : October 4th, 2019-00:44
I feel like I might get a little impatient waiting for these New Duometres!