skyeriding
901
I tried labelling the different components of a Datograph
Hello,
Recently, I stumbled across a wonderful exploded diagram of the Lange Datograph (L951.1) movement - which can be seen as below for those who haven't:
So I thought lets take it a step further. Why not try labelling all the components?
This was my best attempt at it, using various references I found online. I had to guess certain component functionalities as I can't find internal movement photos (e.g. where is the clickspring??). Of course, please correct me where I'm wrong!
Notice that the movement components can be divided into three main subgroups - the base timekeeping module (escapement, geartrain, keyless works), the chronograph module (horizontal clutch, instantaneous jumping minutes), and the big date module ("ones" and "tens" wheel actuated by a 31-toothed calendar wheel).
Of course, the 1815 Chronograph is essentially the same movement but with the big date module removed - the diagram highlights which components are involved.
The main thing to note is simply how many detent springs there are! Many are used for the chronograph module side. They primarily serve two purposes:
- As any pushers in watches have to return back to their original position after being depressed and released, there always needs to be some form of spring to reset that lever.
- The column wheel, instantaneous minute, and date mechanism increments by a fixed rotation per click. Therefore, there is a triangular tipped detent that fixes the position of each wheel in fixed rotations - such that the wheels will cleanly snap in fixed rotation amounts.
I did not bother labelling the screws as they are impossible to follow, however it is noted that some screws on the chronograph sides act as "banking screws" - that are likely meant to adjust the travel angles of the levers and clutch. Perhaps they are eccentric?
Overall, I still find chronographs some of the most fascinating complications in horology to understand their workings. That would be followed by QPs - those have various different solutions as shown by the many brands...
Regards,
skyeriding
This message has been edited by skyeriding on 2016-04-04 08:29:32
I tried labelling the different components of a Datograph
Hello, Recently, I stumbled across a wonderful exploded diagram of the Lange Datograph (L951.1) movement - which can be seen as below for those who haven't: So I thought lets take it a step further. Why not try labelling all the components? This was my be...
Wow～～～
You just did what I've been thinking of doing for a long time. Thanks a lot for the detailed information!
Looks like a great job!
Especially when considering the resource limitations. I immediately was drawn to what you have already identified as the click spring. BTW that is not the balance wheel; it's a crown that may be worn by the person worthy enough to be able to label all the...
Thanks iamcalledryan
Apparently it is the clickspring, with the odd looking part next to it being the click. Regards, skyeriding
It is too late in the evening to digest all but: great job!
I shall read it again tomorrow, with anticipation ! Thanks for the post. Best Moritz
Minor correction..
The lever next to the clickspring I labelled should be the click itself. Quite different than say, an 1815 movement where it's exposed and is finished to a higher degree.. Regards, skyeriding
The Mainspring stopwork could also be named Maltese Cross, which I like more as a term for this detail.
And once more: It is far too late in the evening for me to digest all. I will certainly look again into your fantastic post. Best Moritz
I like the term, but refrained from using it
...as I always thought it's weird calling it as one when it doesn't have four lobes like an actual Maltese cross Interestingly as foversta has pointed out before, newer L951 movements with longer reserves have removed the Maltese cross, as in this photo: ...
here is a titbit for you to answer your question: the wandering nut!
If Lange has used this system (likely) than the answer to your question is: yes, the power reserve indicator can limit the winding. And even more: it can also do the same job as the Maltese Cross in using justvthe linear parts of the main spring. When you...
You reminded me of this, thanks Moritz
I believe the term for this is called a "differential screw", which may be an older way of how power reserve mechanisms works. Off the top of my head, the only wristwatch I know using such a setup is the Bexei Primus. loupiosity.com Such a setup would...
thank you for the links
I would think that the rotations and teeth have all been calculated and that a full wind of the watch would limit the power reserve indicator "naturally". The definitive answer would be only available by Lange themselves, I guess. I am asking myself if La...
I'm unsure about the that, however I found an interesting tidbit..
Reinspected the parts picture and stumbled across this, cropped from the previous knolled photo: That's the differential gear used for the indicator. This is similar to the 1815 u/d as here: Interestingly, even in the first generation of the Datograph L95...
that is interesting indeed!
The plate design makes me wonder if the first Dato was actually planed to have a pr indicator? Maybe Lange went for the Maltese Cross instead, out of design issues at the time? Best Moritz