You should be able to rely on our watches at all times. That’s why we always do a little more than necessary. For example, our woodpecker neck regulator is used in a Mühle watch even if – unlike our S.A.R. Rescue-Timer – it does not have to hold its own during risky rescue operations. We developed the fine adjustment in 2003 to ensure the precise running of our movements even under the toughest operational conditions.
With conventional fine adjustment systems, a strong shock can cause the regulator arm to jump up between the regulating screw and the counter-pressure spring. This can change the position of the balance staff or the regulation of the watch. Our specially shaped woodpecker neck spring prevents the regulator arm from moving upward by engaging a semicircular recess in the regulator arm. In this way, it not only presses the regulator arm laterally against the fine adjustment screw, but also simultaneously downward onto the balance cock.
THE FINE ADJUSTMENT SCREW
The woodpecker neck fine adjustment is a balanced system consisting of a fine adjustment screw, regulator arm and counter-pressure spring. The movement is regulated by turning the fine adjustment screw. This moves the regulator arm and lengthens or shortens the effective length of the balance spring. The fine adjustment screw, in combination with the specially shaped counter-pressure spring, permits particularly sensitive and thus precise regulation of the movement. It is secured against subsequent rotation by a clamping screw.
THE WOODPECKER NECK SPRING
Thanks to its specially shaped end, the counter-pressure spring of the Mühle fine adjustment engages in a semicircular recess of the woodpecker neck hand. In analogy to the woodpecker neck spring, the regulator arm is called the woodpecker neck hand. In this way, the woodpecker neck hand is not only pressed laterally against the fine adjustment screw, but also simultaneously downwards onto the balance cock. In this way, the woodpecker-neck spring fixes the regulator arm in position and thus withstands even stronger vibrations.