Balance wheel

The balance is a component of a clockwork. It serves as a regulator for small clocks, so especially for wristwatches and pocket watches, but eg also for carriage clocks. A balance consists of a balance wheel and hairspring. Precursor of the balance was the restlessness.

The balance is a precision made ​​of metal small flywheel that has pins for mounting on the shaft ends. A coil spring, together with the mass of the wheel an oscillatory system. The accuracy of the balance wheel vibration determines the accuracy of the clock.

The idea of ​​using the balance along with a coil spring was developed according to a proposal by Jean de Hautefeuille by Christiaan Huygens, in 1675 a French patent for it was granted.

Previously, portable watches were equipped for reasons of space with Torsionspendeln. Meanwhile invention pace for portable watches were falsely attributed to Peter Henlein, they were there but in the early 15th century. From Henlein Its oldest portable clock.

Precursor

Until the invention of suitable inhibitory systems, the pendulum had only a satisfactory accuracy, but could not be transported without damage. The first developed in the 15th century portable clocks ( see Nuremberg Egg ), however, were equipped for reasons of space with short Torsionspendeln. However, these were influenced by any movement of the carrier and had many days to maintain error up to minutes.

In principle, the shorter the period of oscillation, the lower are those disorders. Therefore, the invention of the short oscillating balance resulted in a noticeable improvement in the Uhrgangs.

Forms of the balance spring

The inwardly bent end curve was used by Abraham Louis Breguet for the first time to achieve a concentric oscillation of the balance spring, and was among other things by the calculations of Édouard Phillips developed ( Phillips terminal curve ).

Period of the oscillation

The period T of the balance wheel oscillation depends on the moment of inertia I of the balance and the Directorate D moment of their spiral:

It is assumed that the spiral remains in its linear region of operation, and neglecting the damping. A ( reciprocal ) measure of the damping is the quality factor - a quality feature of the movement. A low quality means that each period a considerable portion of the energy contained must be supplied by the inhibition. This makes the clock sensitive to changes in spring tension. A high quality also decreases the impact of periodic disturbances, such as when the wearer of the clock waves or applauded.

In good works the bearings of the shaft journal from corundum exist, formerly from natural sapphires and rubies today from synthetically produced to permit low-friction gear possible.

Thus, the journals are not damaged in collisions, using a shock device, such as Parechoc or Incabloc. The bearing block is mounted movable in case a spring and can avoid collisions. In 1976, developed by George Daniels Co-Axial escapement, the escapement and the energy supply (also called elevation ) are spatially separated, so the wear is reduced and can be dispensed with lubrication.

Regulator

As a regulator is defined as the fine adjustment of a clock.

To check the regulator and thus the accuracy of the watchmaker is a time scale, a device that is measured at the body with a sound - vibration microphone and displayed graphically. A micro - Dynagraph can be used to record the fluctuations of the force moment on the escape wheel, the change in the amplitude of the balance and the gear clock skew.

Compensation

Besides the manual regulator often self-regulating mechanisms to compensate for environmental influences are used.