The invention relates to a method for fabrication of a balance spring of a predetermined stiffness comprising the steps of fabricating a balance spring in dimensions of increased thickness, determining the stiffness of the balance spring formed in step a) in order to remove, locally, a volume of material, in order to obtain the balance spring having the dimensions necessary for said predetermined stiffness.

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 immobilizing 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.

In an oscillator for a timepiece including a balance and a hairspring, the balance lacks equilibrium, such that: the curves for running of the oscillator owing to weight of the hairspring as a function of the oscillation amplitude of the balance in at least four vertical positions of the oscillator spaced by 90 each pass through 0 at an oscillation amplitude of the balance between 200 and 240; and between oscillation amplitudes of 150 and 280, curves representing the running of the oscillator owing to lack of equilibrium in the balance as a function of the oscillation amplitude in the vertical positions each has an average slope of opposite sign to the average slope of the corresponding curve among the curves representing the running of the oscillator owing to the weight of the hairspring. A reduction in the running discrepancies between the vertical positions can thus be achieved.

A method for determining an imbalance characteristic of a hairspring (5) balance (4) oscillator (3) of a timepiece movement (2), the method comprising at least the following steps: Setting the hairspring balance oscillator in an oscillating motion at at least two amplitudes, Determining, for each amplitude and for at least two positions of the oscillator, a piece of data representative of the oscillation period of the oscillator, Using the data from the previous step to calculate the imbalance characteristic of the hairspring balance oscillator.

A method of setting inertia of and/or poizing a timepiece sprung balance assembly including: manufacturing a balance and a balance spring irreversibly assembled to each other; fixing an outer coil of the balance spring in position in a tamperproof manner to a balance spring stud which is immobilized in a tamperproof manner by irreversible attachment to a balance cock; determining a peripheral surface of the balance, every point of which is remote from the balance spring by a first predefined distance; performing a re-machining operation only on the peripheral area.

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 immobilizing 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 winding device, with a motor driving a winding operation, means for acoustic measurement of the oscillator of a watch in the winding position, control means analysing the signals transmitted by the measuring means and comparing them to desired values that can be parameterized to regulate the operation of the motor by starting this motor when the operating amplitude of the oscillator is less than a minimum value, and by stopping this motor when the working amplitude is higher than a maximum value, these acoustic measuring means are fixed in a base behind an sensing opening of the acoustic sensor means, the device includes an acoustic duct which places a receiving port, located inside a chamber for housing a watch, in communication with a transmitting port movable by the motor facing this sensing opening.

A microsystem for setting the rate of a timepiece oscillator, including a wheel/inertia block including an off-center unbalance and a toothing and arranged to pivot with respect to a base plate of the microsystem, which includes an actuator driving a first active click arranged to drive the toothing, and includes a device for stopping the toothing in position, wherein the actuator is a thermomechanical actuator arranged to convert a flow of light energy into a displacement of a distal end of the thermomechanical actuator, which carries a first active click or directly controls a movement of a first active click, and the microsystem is capable of incorporation in a watch including a crystal transparent to predetermined wavelengths ranges and allowing the passage of a light ray to regulate the microsystem.

A method adjusting oscillation frequency of a sprung balance assembly formed at random from balance springs and balance wheels. A production mechanism is set to limit a sample standard deviation of a single batch of balance springs to a predetermined maximum value, and to limit a sample standard deviation of a single batch of balance wheels to a predetermined maximum value within a given unbalance tolerance. The mean of the balance population is classified according to the mean of the balance springs, to obtain a difference corresponding to a maximum inertia decrease value of the balances, between extreme gaussian distribution values of balances and of balance springs. A random balance spring sample is taken from the single batch of balance springs and a random balance from among the single batch of balances. The inertia of the balance is adjusted according to a torque value of the balance spring sample.

A method of improving pivoting of a wheel set for a scientific instrument, including an arbor pivoting or oscillating about an axis, in which: static balancing of the wheel set is performed to bring the center of gravity onto the axis; a desired value is determined for resulting unbalance moment of the wheel set about the axis, corresponding to a predetermined divergence between a first principal longitudinal axis of inertia of the wheel set, and the axis; at a predetermined speed about the axis, the resulting unbalance moment is measured with regard to the axis; and an adjustment of the resulting unbalance moment is made within a given determined tolerance with regard to the desired value, and performed by machining both sides of a median plane including the two secondary axes of inertia of the wheel set.