MECHANISM WITH LOCKING DEVICE, FOR DRIVING HANDS OF ELECTRO-MECHANICAL WRISTWATCH

PROBLEM TO BE SOLVED: To provide a mechanism for driving hands and/or at least one date disc of an electro-mechanical wristwatch.SOLUTION: A mechanism 1 drives hands 8 and 9 of an electro-mechanical wristwatch. The mechanism comprises an electric motor 2, a set of gear wheels 3, 4, 5, 6 and 7 connected to the electric motor 2 to move the hands 8 and 9 forward and backward during each activation of the electric motor 2, and a locking device 20. The locking device 20 includes a piezoelectric actuator 21 which locks one wheel out of the set of gear wheels 3, 4, 5, 6 and 7 directly or via a bolt 22 in an idle mode. The piezoelectric actuator 21 releases the set of gear wheels 3, 4, 5, 6, and 7 to move the hands forward and backward when being activated by an electric signal at the time of each activation of the electric motor 2.