Zenith: How Zenith’s fusee and chain work together

Zenith developed a special complicated watch, the Academy Georges Favre-Jacot, to celebrate its 150th Anniversary in 2014.
Zenith traces the roots of this watch, which is equipped with a fuse-and-chain constant force system, to its development of marine clocks. In this video the head movement designer of Zenith explains the function of a fuse-and-chain, and he also answers to the questions: How do you protect the chain when you’re winding the watch?
And how do you keep the watch running when you’re winding the watch?

[@beshkodiak]

Thank you. I am a young amateur horologist, that is to say: a 71 year old forest dweller who is fascinated by these little engines and enjoys working on them. I have recently acquired a couple of antique fusee watches, with the intent to restore. I enjoyed your video.

[@glennsmooth]

Very informative. It would be nice to see the watch in action and some 3D animation of course :)

[@DrJon-zf2xo]

Very nice. John Harrison would be very pleased to see his maintaining power system still in use.

[@sideleyOriginal]

the fusée chaîne was developed by the French Ferdinand Berthoud, isn't it?

[@1035pm]

@@sideleyOriginal I always thought it got traced back to Leonardo da Vinci?

[@sirpfa]

Thank you very much. I wish there were some animations too...

[@inspectorsteve2287]

Near the end of winding does the spring that keeps the watch going during winding get reset? Or does it get reset as the watch runs under the main spring?

[@andyholton7959]

Awesome thank you 👍

[@SubTroppo]

I would rather see standard style dials on expensive watches so that a glance is all you need, but perhaps one is not meant to use them on a daily basis even if you can afford them.

[@ouraN2O]

Wow that's pretty confusing when you speak english and french and you try to listen to them speaking french but it begins to speak in english...

[@rays5163]

Exactly.

[@eufizaquilo]

1:36 is this Solidworks?

[@karthick86c]

Fusion 360

[@cookiedufour]

yes this is actually solidworks not fusion 360

[@karthick86c]

@@cookiedufour As a long time solidworks user I can confirm this is not solidworks!

[@ShykeProdz]

So it's unlimited energy or what ? 😂

[@crobulari2328]

Energy from the mainspring pulling the fusee via the chain and giving a near linear power output to the train. Thereby improving regularity of beat over time. In old Verge escapement pocket watches this system was essential. Accuracy of timekeeping is improved.

[@intensecutn]

No, it's using stored energy in the spring. The stored energy is from the person winding the clock.