US Patent 8042423 Backlash-compensating gear train for horological mechanism

At least some of the uniformly distributed teeth of one of the antibacklash partner toothed wheel units, of this backlash-compensating gear train for a horological mechanism, have elastic parts (DR) that are flexible in the direction of the respective thicknesses of the teeth. Some of the teeth are capable of temporarily transmitting a torque considerably greater than the normal drive torque. Two adjacent teeth (D1, D2) capable of temporarily transmitting a torque considerably greater than the normal drive torque each comprise one flank (D1a, D2a) integral with a more rigid part (D12), and one flank (D1b, D2b) integral with a more flexible part (D1R, D2R), the two more rigid parts (D12) of the two teeth (D1, D2) being adjacent.