Differential with radial balls for power-reserve indicator

Dara technology

The Dara differential is based on a compact modular concept whereby the two inputs of the differential gear are linked to the teeth of the barrel-drum’s gear and that of the ratchet wheel respectively, the output being linked to the power-reserve indicator.

Patent pending: No. EP1995649A2


  • Independent module, reliable and ready for immediate integration into the movement
  • No friction adjustment
  • No play adjustment
  • Very compact design - d 0.50 x D 4.20 x E 1.00mm
  • Lubrication free

Ready for your development

In order to develop your solution based on this product, consult our Development section by clicking on the link below. 

A team attentive to your concerns

The classical differential systems in watchmaking generally require the watchmaker to intervene for the sensitive adjustment of friction during the assembly of the movement.

Our engineers have designed a pre-set independent module which ensures accuracy and reliability to enable the power-reserve indicator to function correctly. 

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