Swiss & English Lever Escapement

The Swiss lever escapement and the English lever escapement are two types of mechanical watch escapements that are used to regulate the movement of the watch’s balance wheel. The Swiss lever escapement is the most commonly used escapement in modern watches. The main difference between the two is the position of the impulse planes.

In a Swiss lever escapement, the impulse planes are on both the escape wheel’s teeth and the lever 3. In contrast, in an English lever escapement, all the impulse planes are on the lever, and the escape wheel has pointy teeth. This difference in the position of the impulse planes affects the length of the impulse and the number of impulses per second, which can impact the accuracy of the watch. The Swiss lever escapement has a shorter impulse time and a higher number of impulses per second, which results in more accurate timekeeping.

The English lever escapement, on the other hand, has a longer impulse time and a lower number of impulses per second, which can result in less accurate timekeeping.