Basic Elements › Measuring instruments

THE TORSIOMETER

What is a torsiometer?

The torsiometer is a specialized instrument used in horology to precisely measure the torque applied to various moving components of mechanical watches. Its use is essential, particularly during the fine-tuning and quality control of mechanisms, to ensure optimal, durable, and consistent performance of the components.

Functions and applications

• Torque measurement of barrels
  The Barrel, a cell containing the mainspring, is a key element in the transmission of energy. The Torsiometer makes it possible to quantify the torque exerted by the spring on the barrel Arbor during the winding and unwinding of the spring. This measurement is crucial for evaluating the available driving force and its consistency, thus ensuring a power reserve that meets specifications.
• Testing of wheel rivets on their pinion
  During the Assembly of the gear train, the wheels are riveted to their pinions to ensure the transmission of movement. The Torsiometer is used to check the torque required to guarantee perfect cohesion between the wheel and the pinion. Precise torque Regulation / Adjustment ensures the longevity and reliability of the mechanism.
• Torque measurement in the hand-setting
  Some hands withstand immense acceleration and deceleration. This is notably the case for the hands of chronograph during reset to zero. Using a torsiometer, one will therefore check the hold of the hand’s friction fit on its pivot, as well as that of the hand stack relative to its pipe.

Operating principle

The torsiometer measures torque by recording the torsional force applied to a rotating element. This can be done by various means depending on the model: mechanical, electronic, or combined. Some devices use a lever arm connected to a strain gauge or a digital torque sensor, providing immediate and precise feedback on the value of the torque applied.

Importance in horology

The extreme precision required by mechanical watches makes torque measurement essential. An improperly adjusted torque can lead to:

• Accelerated wear of components.
• Energy losses affecting precision.
• A risk of breakage or misalignment of moving parts.

Thus, the Torsiometer is one of the key instruments in industrial watchmaking Testing, particularly during the design, development, and quality control phases.