Unknown (for me) antishock system used by Longines in cca 1952

[setible]

Hi,
do you know what kind of antishock is the one from the pictures below?

 

[Seiji]

How do you know that is an antishock system? Maybe it is just an easier way to maintain the balance wheel mechianism on a mid grade movement.

Edited: Aug 5, 2024

 

[setible]

Seiji

How do you know that is an antishock system? Maybe it is just an easier way to maintain the balance wheel mechianism on a mid grade movement.

I supposed it is... maybe you are right, but i never saw anything like this to a 12.68z

 

[padders]

As noted above, I don’t think that actually is anti shock at all.

 

[setible]

What could it be?

 

[setible]

could this be the "monobloc" ?

 

[DirtyDozen12]

S setible

What could it be?

I have always thought that this was an anti-shock device, as well. It appears on a number of Longines calibers from the early 1950s, as well as all 30CH movements (as far as I know). Like most anti-shock devices, the cap jewel on the balance cock is held in place by a thin piece of metal. This thin piece of metal is not fixed to the cock, but held in place via tension. This is in contrast to designs without shock protection, in which the cap jewel is attached to a ring of metal that is screwed to the cock.

Caliber 12.68Z. Source: eBay


Caliber 23Z. Source: https://watchcharts.com/listing/450...alatrava-mens-military-sei-tacche-watch-steel


Caliber 22AS. Source: https://www.ebay.com/itm/3261871127...J3fOGP4hRqGUkm2r5AkYiLLASz|tkp:Bk9SR4639LWkZA


Caliber 30CH. Source: https://www.carsandwatches.com/watches/longines-30ch-pink-gold-special-case

 

[DirtyDozen12]

I checked Patrick Linder's book, and "Shock-Resist" is mentioned for the 30CH. I also checked a caliber 530/538 repair manual from Peter's Vintage Longines Watches and found this:

Source (page 3): https://drive.google.com/file/d/1IX3_4tg_9lg91bZdiqrZfpGrFqd7WKso/view

Source (page 4): https://drive.google.com/file/d/1IX3_4tg_9lg91bZdiqrZfpGrFqd7WKso/view

 

[setible]

Thank you! Very good info. Chapeau!