The tourbillon
In the course of the 18th century, watchmakers
discovered that the rate deviations of their move-
ments were, in the final analysis, caused by the tiny
hairsprings which together with the balance consti-
tute the oscillator of every timepiece. Since its
center of gravity does not coincide with the
geometric center of the spring, its regular brea-
thing is negatively affected by the earth’s pull in
any orientation except horizontal. The tourbillon
corrects this systemic “positional” error. This is
done by integrating the balance and the escape-
ment in a hinged cage that rotates about its axis
once a minute. On this orbit, the slightly eccentric
center of gravity of the hairspring revolves around
the center of the cage every 60 seconds, so the
positional error is automatically offset by progression,
regardless of the orientation of the spring.
The minute repeater
On demand, the minute repeater strikes the hours,
the quarter-hours, and then the minutes that
have elapsed since the last quarter-hour. The first
hammer strikes the hours on the low-pitched
gong with one strike for each hour. Subsequently,
each quarter-hour is sounded as an alterna-
ting double strike by two hammers on both the
high- and low-pitched gongs. Finally, the second
hammer strikes the high-pitched gong to count
the number of minutes that have passed since
the last quarter-hour. At 12:59, for instance, the
melody consists of 12 low sounds, 3 double
high/low sounds, and 14 high sounds (totaling the
maximum of 32 strikes).
Содержание 5339
Страница 1: ...English Français Deutsch Italiano Español ...
Страница 2: ...English ...
Страница 8: ...Français ...
Страница 14: ...Deutsch ...
Страница 20: ...Italiano ...
Страница 26: ...Español ...