Balance for wristwatch, has flexible element comprising flexible part that is arranged on annular felloe to bend flexible element radially toward exterior based on oscillation of balance, where arms connect hub to annular felloe

摘要

The balance has a hub (11) for receiving a balance shaft (12). Two arms (13) connect the hub to an annular felloe (10). A flexible element i.e. strip, comprises a flexible part (14a) that is arranged on the felloe to bend the flexible element radially toward an exterior based on oscillation of the balance. The strip comprises a rigid part (14b) that is spaced from or brought close to the felloe by a screw (20) to modify static moment of inertia of the balance. The strip extends on sides of a radial flange (16) along an outer side wall of the felloe over an angle of 80 degree.