Abstract: The present invention relates to a mechanical stop and start system for a function of a timepiece, comprising a mass, mounted so as to be able to move on a frame, between a first and a second end position, these being defined respectively by a first stop and a second stop, said mass moving in a bistable manner, under the effect of gravity, tensioning a spring between the first and second end positions, and relaxing said spring between the second and first end positions.

Abstract: A crimping system (1) for a timepiece (6) or jewellery item comprising: a crimping support (3); a precious stone (2) mounted in or on the crimping support (3); and a flexible element (5) fastened to the crimping support (3) in such a way as to flexibly link the crimping support (3) to said item (6), such that the stone (2) can oscillate axially and radially relative to an axis of symmetry (15), following a movement of the item (6); the crimping system (1) further comprising a stop (18, 22) that is more rigid than the flexible element (5), the stop (18, 221, 241) being capable of cooperating with the crimping support (3), in such a way as to limit the range of axial and/or radial movement of the stone (2) when the latter oscillates. In particular, the crimping system (1) has the advantage, relative to the prior art, of allowing much easier and more reliable mounting of the stone (2) and of being better suited to the use of stones (2) of small dimensions.

Abstract: Drive member for timepiece movement comprising: a barrel comprising a drum mounted on an arbor; a main spring wound inside the barrel, and a core coaxial with and pivoting on the arbor; the exterior end of the spring being coupled to the drum and the interior end of the spring being coupled to the core; the exterior end of the spring is coupled to the drum by a first clamp that is pivot-mounted in the drum so that when the spring is unwound, the first clamp pivots in such a way as to hold the exterior turn of the first spring against the drum and when the spring is wound up, the first clamp pivots towards the center of the barrel to follow the exterior turn of the spring. The bending stresses in the spring are reduced.

Abstract: The going train for a timepiece has a mechanical movement having a frame (0), a barrel (1) and an escapement pinion (5) which are connected by the going train. This going train has a stepping-up epicyclic train having a first planet gear (6) with a constant rotational speed during normal operation of the movement, a second planet gear (7) kinematically connected to the escapement pinion (5), at least one satellite gear (9) each meshing with the first planet gear (6) and the second planet gear (7), and a satellite carrier (8) kinematically connected to the barrel (1) and carrying the satellite gear(s) (9).

Abstract: A timepiece movement includes an escapement mobile connected to a barrel by a going train and a spring balance as well as an escapement mechanism (1) including an impulse lever (8) and at least one regulating member (9). The impulse lever (8) and the regulating member (9), which co-operate with the escapement mobile, are controlled by control members (6.1, 6.2, 7.1) supported on the axle of the balance. Between positions in which they co-operate with the escapement mobile (1) and positions in which they do not co-operate with the escapement mobile, the impulse lever (8) and the regulating member (9) move in two different planes forming an angle therebetween.

Abstract: The constant force escapement mechanism in particular for a timepiece movement including a spring balance and an escapement gear connected to a barrel by a going train includes a constant force auxiliary spring (11). It includes an impulsion lever (8) co-operating on the one hand with the escapement gear (1) and on the other hand with control members fixed to the arbor of the spring balance. The constant force auxiliary spring (11) is fixed at one of its ends on a part of the frame of the movement and at its other end to the impulsion lever (8).