Mechanical clock gears

Mechanical clock gears combine millimeter precision and centuries of technical evolution, from early medieval dials to modern chronometers.

About this subject

Gears in a mechanical clock are the heart of the movement, transmitting power from the mainspring to the escapement, which regulates the motion. Each tooth of a cogwheel must be cut with extreme precision to maintain timekeeping accuracy. The first mechanical clocks appeared in Europe in the 13th century, in monasteries and church towers, using weights as power sources. The invention of the anchor escapement by Robert Hooke in the 17th century and the development of the cylinder escapement by Thomas Mudge allowed greater precision and reduced friction. Materials such as brass, steel, and more recently beryllium and silicon alloys are used to minimize wear and thermal expansion. Specialized oils are crucial for reducing metallic friction, and periodic maintenance by a watchmaker ensures longevity. In high horology, gears are often hand-decorated with angles, pearlage, and fusée engraving, demonstrations of craftsmanship and tradition that go back centuries.

Frequently Asked Questions

What is the main function of gears in a mechanical clock?

Gears transmit and modulate the force from the mainspring (or weight) to the escapement, controlling the rotation of the hands and ensuring accurate timekeeping.

What materials are clock gears made of?

Traditionally brass and steel, but modern alloys like beryllium, silicon, and titanium are used to reduce friction, corrosion, and thermal expansion.

How are clock gears lubricated for longevity?

Special synthetic oils are applied to strategic points (pivots, escape teeth) to minimize wear, lubrication is renewed during periodic maintenance.