remontoires

A remontoire is a mechanism in a clock that stores and releases energy at regular intervals, typically to drive the timekeeping train. This is distinct from a traditional weight-driven or spring-driven clock where the mainspring or weight directly powers the gear train. The remontoire acts as an intermediary, accumulating power from the main source and then delivering it in a controlled manner. This controlled delivery helps to maintain a more consistent force on the escapement, potentially leading to improved accuracy.

The concept of a remontoire was developed to address the issue of decreasing force on the escapement as the mainspring unwinds or the weight descends. By periodically rewinding a secondary spring or lifting a small weight, the remontoire ensures that the escapement receives a consistent impulse. This makes the clock's performance less susceptible to variations in the main power source.

Various designs of remontoires exist. Some use a small auxiliary weight that is lifted by the main weight at set intervals. Others employ a secondary spring that is rewound by the mainspring. The primary advantage of a remontoire is its potential to enhance timekeeping precision, particularly in early mechanical clocks where the driving force could fluctuate significantly. While the complexity of remontoires means they are not found in all timepieces, they represent an important engineering development in the history of horology.