A method for adjusting a rate of a timepiece after encasing a movement to ensure a better rate for the timepiece.

A method for adjusting a rate of a timepiece after encasing a movement to ensure a better rate for the timepiece.

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 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.