What effect does gravity have on the accuracy of the Chronograph watch's travel time?

Fanda

2018-10-16

Chronograph stainless steel watch The influence of gravity on the accuracy of the watch's travel time is mainly as follows:

1. The balance spring system is unbalanced, that is, the center of gravity of the system does not coincide with the axis of the pendulum shaft. Usually the mass of the balance spring system is mostly concentrated on the balance wheel itself, and the thickness of the balance wheel is much smaller than the diameter. Therefore, the balance spring system is unbalanced, that is, the deviation of the center of gravity occurs in the symmetry plane of the thickness of the balance wheel. Inside. Since the eccentricity of the system will directly affect the swing period of the balance wheel, the period will increase, and the watch will slow down when it goes. Conversely, the cycle is reduced, and the watch will go faster when it goes. The daily difference can minimize the eccentricity of the balance by means of static balance and dynamic balance. This is the most direct and effective way to reduce the influence of system imbalance on the cycle. However, it is impossible to create an ideal balance wheel that is absolutely eccentric.

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2. The gravity effect of the fixed point of the hairspring, that is, the influence of the center of gravity of the hairspring on the cycle. Since the hairspring cannot maintain the shape of the Archimedes spiral when it is stretched, the center of gravity of the hairspring changes in a very complicated trajectory during movement. When the pendulum shaft is placed horizontally, the additional moment generated by the center of gravity of the balance spring on the pendulum shaft is directly superimposed on the balance spring torque. Since the additional moment generated by the center of gravity on the pendulum axis is non-linear, it will cause the system to generate isochronous errors.

3.Chronograph 3 eyes watch The pendulum axis changes the amplitude of the flat position. When the pendulum shaft is placed vertically, the end face of the journal is in contact with the bearing, and when placed horizontally, the outer circumference of the journal is in contact with the bearing. The friction torque of the former is smaller than that of the latter, which results in a higher amplitude of the balance when the pendulum shaft is placed vertically than when placed horizontally. Because any one of the balance spring systems has a certain time difference, the result of the amplitude change will cause a periodic change accordingly.

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4. There are axial or radial clearances between the escapement pinion and the fork shaft and the bearing in the escapement. When placed vertically, the end face of the journal and the bearing contact create an axial gap. When placed horizontally, the outer circumference of the journal and the bearing contact create a radial gap, which causes the operating state of the escapement to change, resulting in a bit difference.

5. The effect of the gap between the fast and slow needle clips and the hairspring on the cycle. The common fast and slow needle system is adjusted by the speed of the needle. Since the balance spring and the clip do not get stuck in order to dial the fast and slow needle, a certain gap should be left between the balance spring and the clip. When the watch is in different positions, the position of the hairspring in the fast and slow needle clips will change due to the gap, so that the actual working length of the hairspring changes, resulting in a bit difference. Among the above factors, the balance spring system is unbalanced and the balance of the hairspring is fixed.

Chronograph luxury watches Force effect and pendulum axis transformation The three main factors that cause the difference in the amplitude of the flat position change. The first two factors can reduce the difference by increasing the isochronism of the balance spring system, while the third factor can reduce the difference by reducing the difference in energy consumption between the balance springs of the balance shaft. However, it is impossible to completely guarantee that the center of gravity of the balance spring and the balance wheel are constant. The eccentricity of the balance wheel and the balance spring is technically limited, and it is difficult to solve these problems by conventional methods. Therefore, the watchmaker Breguet proposed the tourbillon technology, which solved the vertical difference of the watch from the working principle. It placed the balance spring system and the escapement in the rotating frame, while running itself. It can also make 360-degree rotation together, which can effectively compensate the position error caused by the gravity of the balance wheel, the eccentric motion of the balance spring, the azimuth angle of the balance spring, etc., and minimize the position error of the watch caused by the gravity of the earth.