Tourbillon
From Biocrawler, the free encyclopedia.
A tourbillon (French for "whirlwind") is a type of mechanical clock escapement invented in 1795 by Abraham-Louis Breguet that is designed to counter the effects of gravity and other perturbing forces that can affect the accuracy of a chronometer. This is accomplished by mounting the escapement in a rotating frame, so that the effect of gravity cancels out when the escapement is rotated 180°. The effects of gravity were particularly problematic when pocketwatches were carried in the same pocketed position for most of the day. In a tourbillon, the entire escapement assembly rotates, including balance wheel, escapement wheel and pallet fork. The rate of rotation varies per design but would typically be around one revolution per minute.
The tourbillon is considered to be the most complex of watch complications and is valued for its engineering and design principles. In modern watch designs a tourbillon is not required to produce a highly accurate timepiece. Nevertheless, the tourbillon is one of the most valued complications of collector's watches and premium timepieces.
In the late 20th century, the first research into multi-axis tourbillon movements was done by British clockmakers Anthony Randall and Richard Good, eventually producing two and three axes tourbillon movements.fr:Tourbillon
