balance spring

American  

noun

Horology.

1. hairspring.

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Etymology

Origin of balance spring

First recorded in 1880–85

Example Sentences

The spiral balance spring revolutionized the accuracy of watches, enabling them to keep time to within a minute a day.

From Scientific American • Dec. 31, 2011

In 1675 Huygens devised another fundamental improvement, the spiral balance spring.

From Scientific American • Dec. 31, 2011

Through this work, Hooke came up with the idea of a new kind of pocket watch regulated by a balance spring.

From "The Scientists" by John Gribbin

He invented the spiral balance spring still used in some watches today; made fundamental contributions to mechanics—e.g., the calculation of centrifugal force—and, from a study of the game of dice, to the theory of probability.

From "Cosmos" by Carl Sagan

To do so we remove our balance spring and place the balance in position.

From Watch and Clock Escapements A Complete Study in Theory and Practice of the Lever, Cylinder and Chronometer Escapements, Together with a Brief Account of the Origin and Evolution of the Escapement in Horology by Anonymous