Patent ID: 6863434

Claim:
Constant-force device comprising a stop wheel ( 12 ) attached to a stop wheel pinion ( 12 a ), an escape wheel ( 6 ) attached to an escape wheel shaft ( 9 ), a tension ring ( 7 ) attached to a tension ring pinion ( 8 ), and a cam ( 5 ) attached to the escape wheel shaft ( 9 ) where the movement of the escape wheel ( 6 ) is blocked or released by two anchor pallets of a first anchor ( 4 ) and where the movement of the stop wheel ( 12 ) is blocked or released by two anchor pallets ( 11 a , 11 b ) of a second anchor ( 11 ) that is controlled by a fork-shaped part of this second anchor ( 11 ) engaged with the cam ( 5 ), characterized in that it comprises a force balance mechanism securing transmission of a constant torque to the regulating organ of a watch by compensating the loss of tension of a spring ( 10 ) that provides the driving energy.