Anti-tripping device for escape mechanism of wristwatch movement, has movable bistable assembly comprising rotor fixed on balance, and amplitude limitation unit for limiting amplitude or angular pivotment of balance during impact

摘要

The device (1) has a limitation pin (5) fixed to a plate (3), and a movable bistable assembly (8) comprising a rotor (9) fixed on a balance (2) and a bistable lever (11) moving pivotingly relative to the rotor around a pivot axis (D2) on a limited angular sector between indexing positions occupied by an indexing unit for storing a state of the balance. A portion of trajectory of the lever interferes with the pin during pivotment of the balance. The assembly includes an amplitude limitation unit for limiting amplitude or angular pivotment of the balance during impact. The escape wheel of the device is formed of micro-machinable material or silicon or quartz or alloy provided from microelectromechanical system (MEMS) technology or alloy obtained by deep reactive-ion etching (DRIE) or lithography, electroplating, and molding (LIGA) process or partially amorphous material. An independent claim is also included for an escape mechanism comprising a mobile part pivoting with respect to a plate.