{"id":10531,"date":"2016-03-17T09:00:35","date_gmt":"2016-03-17T08:00:35","guid":{"rendered":"http:\/\/preprod.gmtmag.com\/?p=10531"},"modified":"2016-06-23T09:20:46","modified_gmt":"2016-06-23T07:20:46","slug":"double-or-nothing-with-two-balance-springs","status":"publish","type":"post","link":"https:\/\/www.gmtmag.com\/en\/technique-n-en\/technique-technique-n-en\/double-or-nothing-with-two-balance-springs.html","title":{"rendered":"Double or nothing with two balance-springs"},"content":{"rendered":"
\n

A real precision-timing powerhouse,<\/strong> the RM031 Haute Performance features two balance-springs among its other technical solutions.<\/p>\n

The Millenary Quadriennium<\/strong> uses the Audemars Piguet escapement and a double balance-spring.<\/p>\n

 <\/p>\n

The balance-spring works with the balance-wheel to regulate the rate of the watch. Together, they form the source of precision. By definition, a single balance-spring is enough and yet several brands use two. Not two separate escapements, as in the case of a double tourbillon, but indeed two balance-springs coupled with a single balance-wheel. Why? Because an escapement with a double balance-spring delivers a more regular, stable and sustainable rate than one with a single regulating spring.<\/p>\n

 <\/p>\n

Stability<\/strong><\/p>\n

The first beneficial effect of double balance-springs is that their oscillations are more centered. That might seem like a detail, but this topic is essential. A balance-spring changes shape constantly, successively contracting and expanding concentrically in step with the oscillations of the balance-wheel. This means its center of gravity shifts. It causes the balance-staff to move in its pivots, thereby generating considerable friction and loss of energy that have been a major cause of concern for watchmakers over many centuries. One can significantly alleviate this friction by means of two balance-springs when they are set against each other, meaning fitted top to tail. When the first contracts, the other expands; and when the center of gravity of one of them shifts to the right, the other moves to the left. The two balance-springs thereby cancel out their respective variations, which means that the balance-staff rubs far less.<\/p>\n

 <\/p>\n

\"\"<\/p>\n

 <\/p>\n

The Galet Tourbillon by Laurent Ferrier<\/strong> uses two balance-springs to achieve record-breaking chronometry.<\/p>\n

The Royal Oak<\/strong> Double Balance Wheel Openworked innovates with two balance-wheels set against each other on the same axis.<\/p>\n

 <\/p>\n

Endurance<\/strong><\/p>\n

The second benefit of this double hairspring approach is that precision is less affected by shocks. The latter shake the balance-spring and balance-wheel, which must rapidly regain a regular rate. This capacity to bounce back to the correct frequency is known as regulating force. With the energy derived from the two springs, the balance-wheel is more rapidly restored to working order and the chronometry is less perturbed.<\/p>\n

 <\/p>\n

Twin natures<\/strong><\/p>\n

These chronometry factors can only work effectively on one condition\u2009: the two balance-springs must feature the same characteristics, the same shapes to the nearest micron, in order for the errors of one to cancel out those of the other. H. Moser & Cie was the first brand to popularize this process. The two balance-springs stem from the same metal casting, the same spool of wire\u2009; they are coiled against each other and fired together. They are identical twins.<\/p>\n

\n

 <\/p>\n

\"\"<\/p>\n

On its self-winding tourbillon movement,<\/strong> H. Moser & Cie uses a double balance-spring, a field in which the brand played a pioneering role.<\/p>\n

In addition to a diamond lever <\/strong>and lever wheel, Leroy leverages the double balance-spring principle by means of its sister company specializing in escapements and balance-springs.<\/p>\n

The balance-spring with double balance-wheel<\/strong>\u00a0in silicon of the Breguet Classique Chronom\u00e9trie 7727.<\/p>\n

 <\/p>\n

Popularity<\/strong><\/p>\n

This principle has been emulated, often in extremely refined models. Leroy uses escapements produced by its sister company MHVJ, which makes balance-springs, and knows how to pair them in an ideal way. The Classique Chronom\u00e9trie by Breguet, which oscillates at a rate of 10 Hz, is equipped with such twinned silicon balance-springs featuring highly sophisticated terminal curves. Audemars Piguet has even taken things to the next level with its new Royal Oak Double Balance Wheel. Two balance-wheels, each with its own hairspring, are mounted on the same staff but work in opposition, thereby procuring the same benefits as a double balance-spring. They must be paired and adjusted like twins, which is a very tough challenge. The brand claims a massive 30% increase in precision compared with a conventional escapement. So doubling up can clearly take all manner of new forms\u2026<\/p>\n

<\/div>\n
<\/div>\n<\/div>\n<\/div>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

A real precision-timing powerhouse,<\/strong> the RM031 Haute Performance features two balance-springs among its other technical solutions.<\/p>\n

The Millenary Quadriennium<\/strong> uses the Audemars Piguet escapement and a double balance-spring.<\/p>\n

 <\/p>\n

The balance-spring works with the balance-wheel to regulate the rate of the watch. Together, they form the source of precision. By definition, a single balance-spring is enough and yet several brands use two. Not two separate escapements, as in the case of a double tourbillon, but indeed two balance-springs coupled with a single balance-wheel. Why? Because an escapement with a double balance-spring delivers a more regular, stable and sustainable rate than one with a single regulating spring.<\/p>\n

 <\/p>\n

Stability<\/strong><\/p>\n

The first beneficial effect of double balance-springs is that their oscillations are more centered. That might seem like a detail, but this topic is essential. A balance-spring changes shape constantly, successively contracting and expanding concentrically in step with the oscillations of the balance-wheel. This means its center of gravity shifts. It causes the balance-staff to move in its pivots, thereby generating considerable friction and loss of energy that have been a major cause of concern for watchmakers over many centuries. One can significantly alleviate this friction by means of two balance-springs when they are set against each other, meaning fitted top to tail. When the first contracts, the other expands; and when the center of gravity of one of them shifts to the right, the other moves to the left. The two balance-springs thereby cancel out their respective variations, which means that the balance-staff rubs far less.<\/p>\n

 <\/p>\n

\"\"<\/p>\n

 <\/p>\n

The Galet Tourbillon by Laurent Ferrier<\/strong> uses two balance-springs to achieve record-breaking chronometry.<\/p>\n

The Royal Oak<\/strong> Double Balance Wheel Openworked innovates with two balance-wheels set against each other on the same axis.<\/p>\n

 <\/p>\n

Endurance<\/strong><\/p>\n

The second benefit of this double hairspring approach is that precision is less affected by shocks. The latter shake the balance-spring and balance-wheel, which must rapidly regain a regular rate. This capacity to bounce back to the correct frequency is known as regulating force. With the energy derived from the two springs, the balance-wheel is more rapidly restored to working order and the chronometry is less perturbed.<\/p>\n

 <\/p>\n

Twin natures<\/strong><\/p>\n

These chronometry factors can only work effectively on one condition\u2009: the two balance-springs must feature the same characteristics, the same shapes to the nearest micron, in order for the errors of one to cancel out those of the other. H. Moser & Cie was the first brand to popularize this process. The two balance-springs stem from the same metal casting, the same spool of wire\u2009; they are coiled against each other and fired together. They are identical twins.<\/p>\n

\n

 <\/p>\n

\"\"<\/p>\n

On its self-winding tourbillon movement,<\/strong> H. Moser & Cie uses a double balance-spring, a field in which the brand played a pioneering role.<\/p>\n

In addition to a diamond lever <\/strong>and lever wheel, Leroy leverages the double balance-spring principle by means of its sister company specializing in escapements and balance-springs.<\/p>\n

The balance-spring with double balance-wheel<\/strong>\u00a0in silicon of the Breguet Classique Chronom\u00e9trie 7727.<\/strong><\/p>\n

 <\/p>\n

Popularity<\/strong><\/p>\n

This principle has been emulated, often in extremely refined models. Leroy uses escapements produced by its sister company MHVJ, which makes balance-springs, and knows how to pair them in an ideal way. The Classique Chronom\u00e9trie by Breguet, which oscillates at a rate of 10 Hz, is equipped with such twinned silicon balance-springs featuring highly sophisticated terminal curves. Audemars Piguet has even taken things to the next level with its new Royal Oak Double Balance Wheel. Two balance-wheels, each with its own hairspring, are mounted on the same staff but work in opposition, thereby procuring the same benefits as a double balance-spring. They must be paired and adjusted like twins, which is a very tough challenge. The brand claims a massive 30% increase in precision compared with a conventional escapement. So doubling up can clearly take all manner of new forms\u2026<\/p>\n

<\/div>\n
<\/div>\n<\/div>\n","protected":false},"author":11,"featured_media":16433,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[505],"tags":[99,269,483,565,720,185],"_links":{"self":[{"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/posts\/10531"}],"collection":[{"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/comments?post=10531"}],"version-history":[{"count":1,"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/posts\/10531\/revisions"}],"predecessor-version":[{"id":16377,"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/posts\/10531\/revisions\/16377"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/media\/16433"}],"wp:attachment":[{"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/media?parent=10531"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/categories?post=10531"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gmtmag.com\/en\/wp-json\/wp\/v2\/tags?post=10531"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}