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Something to consider
Never mind the minutes. I’ve often thought that the hours register could jump as well. So why not? The reality for most mechanical chronographs is the jump of the minutes register is semi-instantaneous, not instantaneous. The irreversible jump is engaged like half a second before the minute is up. Lange is the exception to this rule, having developed a true jumping minute.
The semi-instantaneous jump can lead to catastrophic failure in timing, if you stop the chronograph between something like 59.0 and 60.0 seconds. Bad if you’re timing a 25 minute event.
For the consideration of chronograph caliber enthusiasts...
Good day chronograph enthusiasts! Though some may argue that a rotating bezel is a far simpler solution to most daily time-keeping requirements (parking meter, 3-minute egg, et al), we who are devoted to this significant advance in horology will always ar...
Something to consider
Never mind the minutes. I’ve often thought that the hours register could jump as well. So why not? The reality for most mechanical chronographs is the jump of the minutes register is semi-instantaneous, not instantaneous. The irreversible jump is engaged ...
Very interesting! This is just the sort of info I was looking forward to. And yes, certainly I have noticed the "semi-instantaneous" nature of the jump. Lang, eh?
Wouldn't you know. I'd love to know more abot the difference, and how this was achieved. Do you have a suggestion of where might I look? Many thanks for your response! Have a fine day. (Second, never mind the pun, your notion that the hour, too, might "ju...
Well, I did...results surprised me
Stopped two watches between 59 and 60s. Lemania 2320 - minute hand on register stops fractionally between 0 and 1 min. Glashutte Cal 61 - minute hand completes jump to 1 min, once sequence starts. For what it’s worth, it seems that different semi-instanta...
My rudimentary understanding of chronograph movements is that typical 'jumping' minute counters . . .
. . . are actuated by a spring, which is relatively simple to implement. Continuous operation would imply a drive-train, which would be more costly to implement, and possibly expend more energy. Art
We are clever guys, let's think this through
There’s a 7750 Chrono system shown here (in the midst of an IWC watch) The crown is at 3 and the minute counter below 12; hours above 6. Ignoring all the start / stop functions, here is its driving system. As Art noted, revolving gear 8447 with a spring a...
Mike, we can always "count" on you. Many thanks for this cut&paste which has taught me (us?) quite a lot about the amazing usefulness of the chronograph! Now to
practice! (Just like a musician, eh?) But really... I wonder if NASA trained the astronauts in these many practical uses of the Speedmasters they wore, lo these 50 years ago. I seriously doubt it! I aim to write to Lange to see if someone will reveal (or ...
Richard should know the book, I believe he was at IWC when that watch was made
He developed the split second complication on top of the 7750 Cazalea
That a spring might expend less energy than an end-to-end drive-train is a surmise . . .
. . . predicated on its capacity to act as a reservoir. A drive-train would necessarily require constant delivery. Perhaps Richard H can be persuaded to comment. Art
