An inertial mass (1) intended to be mounted on a regulating organ (10), particularly of a horological movement, the inertial mass being configured to be subjected to a rotary oscillation movement at a predetermined frequency, the inertial mass including a rigid main body (2), characterised in that it comprises a flexible inertial element (3) assembled with the main body (2), the flexible inertial element (3) being configured to modify the geometry of the inertial mass (1) according to the oscillation amplitude. Also, a regulating organ and a horological movement comprising such an inertial mass.

The invention relates to a method of manufacturing a plurality of mechanical resonators in a manufacturing wafer, the resonators being intended to equip a regulating member of a timepiece, the method comprising the following steps: (a) fabricating a plurality of resonators in at least one wafer according to reference specifications; (b) measuring the actual frequency of each of the plurality of resonators; (c) determining the offset of the actual frequency of the resonators with respect to the reference specifications; and (d) applying on at least one of the resonators at least two masses from a series of tuning masses to compensate the offset of the concerning resonator to bring the resonator closer to the reference specifications.

A balance for a horological movement, including rigid parts constituted by a hub defining the pivot axis of the balance, at least one felloe sector, at least one arm connecting the at least one felloe sector to said hub, and including a slot for receiving and gripping in position an inertia-block, the slot opening into a housing delimited on the one hand by a rigid part of the balance, and on the other hand an elastic arm including a first end integral with a rigid part of the balance, and a second free distal end. The elastic arm can have a body of a non-constant section, a part of the body having a greater thickness than the rest of the elastic arm so as to have a larger volume of material under stress and store a maximum of elastic energy.

A balance for a horological movement, including rigid parts including a hub defining the pivot axis of the balance, a felloe sector, at least one arm connecting the felloe sector to the hub, and including a slot for receiving and gripping an inertia-block in position, the slot opening into a housing delimited on the one hand by a rigid part of the balance, and on the other hand an elastic arm including a first end integral with a rigid part of the balance, and a second free distal end. The elastic arm has a hook-shaped body, the free distal end of the hook being parallel to a part of the balance having a rigidity greater than or equal to that of the elastic arm.

A process for producing a metal alloy balance wheel by molding includes a) making a mold in the negative shape of the balance wheel; b) obtaining a metal alloy that has a thermal expansion coefficient of less than 25 ppm/° C. and is able to be in an at least partly amorphous state when it is heated to a temperature between its glass transition temperature and its crystallization temperature; c) putting the metal alloy into the mold, the metal alloy being heated to a temperature between its glass transition temperature and its crystallization temperature so as to be hot-molded and to form a balance wheel; d) cooling the metal alloy to obtain a balance wheel made of the metal alloy; and e) releasing the balance wheel obtained in step d) from its mold. The process also includes a step for over-molding flexible centering components in the hub.

A method for the fine adjustment of the rate of a mechanical oscillator with an oscillating inertial mass, equipped, in a first step, with an actuator made of material suitable for irreversible local micro-expansion under the action of laser fires, to impart to an inertia-block a radial travel during suitable laser fires on a writing zone of the actuator, in a second step, the initial rate of the oscillator is set and measured, in a third step, the direction and the value of the deviation required to achieve a predetermined rate range, and of the travel to be imparted to inertia-blocks are calculated, in a fourth step, a writing zone is subjected to femtosecond laser fires to create expansion lines by local molecular expansion to radially deform the actuator, in a fifth step the rate is measured and the third step and fourth step are repeated if required.

Watch comprising a movement, with a timepiece balance wheel comprising a ring distinct from the balance rim, carried by a flange with respect to which this ring is movable in rotation to modify the position of inertia blocks elastically carried by the flange, each able to be indexed in different stable angular positions corresponding to a different inertia of the timepiece balance wheel, the movement further including an operating member movable between coupled and uncoupled positions which includes a stop means for immobilising the rim in a coupled position, and a control means for rotating the ring to modify the position of the inertia blocks in the coupled position, the watch including a crown controlling the control means, a rotating coupling ring controlling the coupling/uncoupling of the operating member through contactless interaction with an external adjustment tool.

Watch comprising a movement, with a balance comprising a ring distinct from the balance rim, elastically fixed to a flange with respect to which this ring is movable in rotation to modify the position of inertia blocks elastically carried by the flange, each able to be indexed in different stable angular positions corresponding to a different inertia of the balance, the movement including an operating member movable between coupled and uncoupled positions which includes a stop means for immobilising the rim in a coupled position, and a control means for rotating the ring to modify the position of the inertia blocks in the coupled position, the watch including a crown controlling the control means, a rotating coupling ring controlling the coupling/uncoupling of the operating member through contactless interaction with an external adjustment tool.

A balance for a horological movement includes rigid portions consisting of a hub defining the pivot axis of the balance, a felloe, four arms connecting the felloe to the hub, and including four slots for receiving and gripping in position an inertia-block, each slot being delimited by an arm and by an elastic arm including a first end integral with the arm, and a second distal end free in relation to the hub, to the arm, and to the felloe sector. The balance includes two pairs of inertia-blocks, each pair of inertia-blocks having different masses to ensure different adjusting powers, a first pair of inertia-blocks for a basic adjustment, and second pair of inertia-blocks for a precise adjustment.

A balance wheel-spring system including a balance wheel that oscillates about a balance wheel shaft and a spring, one inner spiral of which is fixed to the balance wheel shaft or to a collet mounted integrally with the shaft and one outer spiral of which is fixed to a stud integral with a bridge. The balance wheel includes a hub, a rim, an arm connecting the hub to the rim, a front face which includes a countersink and a rear face, the arm including a housing receiving and retaining a flyweight, and the spring being mounted opposite the front face of the balance wheel. The flyweight is mounted on the arm on the rear face of the balance wheel, the distance between the bottom of the countersink of the front face of the balance wheel and the spring is a predetermined interval between 0.05 mm and 1.50 mm.