Product: Watch
Linear Mechanical Wristwatch   (+10)  [vote for, against]
Tickety boo.

Notwithstanding the current fad for huge oversize watches, mechanical watch movements are generally designed to be as compact as possible.

A mechanical watch movement is basically a spring- driven set of gears, with one gear (the escape wheel) regulated by the oscillation of the balance-wheel. Typically, the gears are laid out in a sort of spiral pattern, with each gear overlapping the next and the whole thing wrapped around on itself. It's further compacted by having the hour, minute and second gears mounted coaxially.

I think it would be pretty (if pretty impractical) to have the gear-train laid out linearly, from beginning to end. The resulting watch would be long (maybe 2 inches) and narrow (half an inch or less), and would have the hours, minutes and seconds (and day, date) pointers arranged consecutively instead of coaxially. It would have to be worn along the arm, perhaps with the second and minute pointers at the wrist-end for ready visibility.

Such an arrangement would lend itself well to the other current fad for "open heart" watches in which part of the movement is visible through the dial (and through a transparent display-back).
-- MaxwellBuchanan, Aug 23 2011

Sort of like this http://i923.photobu...ear/Linearwatch.jpg
only not quite. [MaxwellBuchanan, Aug 23 2011]

Here's the hight tech version of the Buchanan/Lurch design http://www.100percentdesign.net/node/574
[doctorremulac3, Aug 24 2011]

Another version http://elitechoice....ar-watch-is-opus-9/
Needs to be more steampunky though. [doctorremulac3, Aug 24 2011]

If you were to go with the 'visual gubbinz' look, it would really cool to have the hands be chain-driven, running along tiny tracks.

[+] for rude style.
-- Alterother, Aug 23 2011


I think you'd run into friction issues, but that would be pretty. An alternative would be to have a pointer engraved on the surface of the relevant gears, rather than a distinct pointer.
-- MaxwellBuchanan, Aug 23 2011


You could have little diamond-shaped worm-gear-driven indicators that run up & down the track, reversing at each end (that's a fairly simple & common little mechanical trick). Then have the scale flip over at each reversal, so the hours start at midnight on a white-on-black AM scale, flip over at noon and run back the other way for 12 hours on the black-on-white PM scale. Hours and minutes likewise - I'm remembering the little pointers on the sickbay monitors from the original Star Trek.
-- lurch, Aug 23 2011


[+] There's much to be said for the compact design of the modern wristwatch... but layed out like that would certainly look good; quite steampunk too.
-- FlyingToaster, Aug 23 2011


//little diamond-shaped worm-gear-driven indicators//

Ooh! I like that. But I can't draw it. The illustrated version uses rubies on the hour, minute and second wheels.
-- MaxwellBuchanan, Aug 23 2011


// friction issues //

I didn't envision the chain moving any faster than the hand(s), but if that's a problem, a little bit of graphite goes a long, long way.
-- Alterother, Aug 23 2011


Even a very small load on the second hand will stop it, so you'd have to be very frictionlessy.
-- MaxwellBuchanan, Aug 23 2011


Teflon in the tracks, no sharp edges or corners, nano-scale dry lubricant, precision micro-machining to ensure nothing moves the slightest bit out of alignment. That's my best shot.
-- Alterother, Aug 23 2011


Bun for steampunkyness.
-- 8th of 7, Aug 23 2011


You can't really get away with not having a coaxially fixed large&small gear for each hand since a direct 60:1 diameter ratio isn't feasible.

Unless you wanted to add more gears in between, the circles would overlap (like the Audi or Olympic logos). Though the concept of a chaindrive is hard to put aside.

Wound either by pulling a loose metal chain, or autowound with a (comparatively) large "pendulum" thing that, if you remain quite still, will slowly move horizontally back and forth powered by the mainspring purely to catch people's motion sensor attention, but if you move your wrist around it swings back and forth winding the mainspring. Maybe even wound by the second hand instead of a separate pendulum though that would require it to be rather heavy.

The mechanism would have to be quite robust of course, to survive shirtcuffs and the like, but there's room to make them so, given no thickness constraints as in an enclosed multilevel thin wristwatch.

The mounting frame is hidden on the inside of the wristband; only the axles poke through (with the gears etc. on top of course).
-- FlyingToaster, Aug 23 2011


//You can't really get away with not having a coaxially fixed large&small gear for each hand//

Yes you can. In a regular watch, the minute wheel is geared to the hour wheel through a little intermediate wheel - it's only for compactness that the minute and hour wheels are coaxial. In fact, coaxiality is a nuisance, because you have extra friction between the axle of the minute wheel and the cannon-pinion (which is the gear that carries the hour hand, and sits like a collar over the minute wheel).

Also, many older watches have a small-seconds, which means that the seconds hand is in a small sub-dial of its own, not coaxial with the other hands.
-- MaxwellBuchanan, Aug 23 2011


That's what I meant, though I messed up the intermediate gears bit. An Ouroboros layout (a circle with decreasing gear size) might look fetching as well the linear.
-- FlyingToaster, Aug 23 2011


Ah, OK.

If the minute and hour wheels aren't coaxial, you could do away with the intermediate gear - the ratio is only 12:1 (the minute hand goes around 12 times as the hour hand goes once; unless you have a 24hr watch). In fact you'd be better off because the whole cannon-pinion business is a clunky solution.
-- MaxwellBuchanan, Aug 23 2011


Ha - you can eat my Pasta Clock!
-- xenzag, Aug 24 2011


Big bun for the linear lurch version of this.
-- doctorremulac3, Aug 24 2011


I do like the styling of the second link, but it's not mechanical, and also I note that the time is displayed digitally as well so that you can actually read it.

The third link is mechanically brilliant but as uggerly as sin.
-- MaxwellBuchanan, Aug 24 2011


Yea, true that. South end of a north bound moose ugly.

I'll take the one in the second link though if somebody wants to buy if for me to stimulate the economy or whatever.
-- doctorremulac3, Aug 24 2011



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