Abstract: The mechanism avoids the rate variations due to the effect of gravitation on a regulating organ of a timepiece whose regulating organ includes a sprung balance and an escape wheel mounted onto a platform. The platform includes an unbalance and is mounted so as to freely rotate about at least a first axis relative to a plate of the movement so that this platform will rotate about the first axis under the effect of terrestrial gravitation. This mechanism includes a wheelwork with a driving kinematical chain linking the escape wheel to a barrel system of the timepiece, and a corrective kinematical chain compensating the movements and speed of the platform relative to the plate, so that these movements of the platform will not perturb the chronometry of the timepiece, this wheelwork including one or several epicycloidal gear trains, each of which contains wheels with straight toothing exclusively.