The present invention relates to a wristwatch comprising a mechanical clock movement with a tuning fork resonator. The oscillator preferably comprises a material A with a low internal friction. In the oscillator of the invention, the unwanted symmetrical oscillations are avoided, for example, by the choice of the materials from which the tuning fork is manufactured. According to preferred embodiments, the rod and/or fastening of the oscillator comprises a material having greater internal friction than that of said material A, such that the quality factor Q.sub.2 of the symmetrical oscillations is reduced, in contrast to the quality factor Q.sub.1 of the anti symmetrical oscillation mode.

The invention concerns an oscillator for a timepiece movement, comprising a staff rigidly connected to a balance carrying first and second bipolar magnets spaced apart from the staff and capable, depending on the angular position of the balance, of being positioned alternately within range of a magnetic field produced by a fixed bipolar magnet, the latter being located on the trajectory of the first and second bipolar magnets and being arranged in such a way that, when one of the bipolar magnets approaches the fixed bipolar magnet, identical polarities are located opposite each other in order to produce a repulsive force. The oscillator further comprises a pallet assembly and an escape wheel for establishing a kinematic connection between a source of energy of the timepiece movement and the balance staff, and arranged in such a way that the balance is capable of having a sustained periodic oscillating movement of an amplitude greater than 90 degrees.

A mechanical oscillator endowed with a strip, with the aforesaid strip incorporating a first silicon layer having a crystal lattice extending along a first direction of one plane, a thermal compensation layer composed of a material having a Young's modulus thermal coefficient of opposite sign to that of the silicon, and a second silicon layer having a crystal lattice extending in a second direction of the plane, with the first and direction being offset at an angle of 45° within the plane of the layers, and with the thermal compensation layer extending between the first and second silicon layers.

A mechanical oscillator endowed with a strip, with the aforesaid strip incorporating a first silicon layer having a crystal lattice extending along a first direction of one plane, a thermal compensation layer composed of a material having a Young's modulus thermal coefficient of opposite sign to that of the silicon, and a second silicon layer having a crystal lattice extending in a second direction of the plane, with the first and direction being offset at an angle of 45° within the plane of the layers, and with the thermal compensation layer extending between the first and second silicon layers.

A timepiece includes an arithmetic circuit, a first switch that controls connection of a temperature compensation table storage to a power supply circuit, and a second switch that controls connection of a device-difference compensation data storage to the power supply circuit. The arithmetic circuit calculates a compensation amount based on a temperature measured by a temperature detector, a temperature compensation data, a device-difference compensation data, and outputs to a frequency adjustment control circuit and a theoretical regulation circuit. The first switch is controlled to the connect state during a first power supply connection period including a temperature compensation data read period. The second switch is controlled to the connect state during a second power supply connection period including a device-difference compensation data read period.

A timepiece includes an arithmetic circuit, a first switch that controls connection of a temperature compensation table storage to a power supply circuit, and a second switch that controls connection of a device-difference compensation data storage to the power supply circuit. The arithmetic circuit calculates a compensation amount based on a temperature measured by a temperature detector, a temperature compensation data, a device-difference compensation data, and outputs to a frequency adjustment control circuit and a theoretical regulation circuit. The first switch is controlled to the connect state during a first power supply connection period including a temperature compensation data read period. The second switch is controlled to the connect state during a second power supply connection period including a device-difference compensation data read period.

Disclosed is a method for manufacturing a horological component according to which a silicon-based piece having the desired shape of the horological component is produced and the piece is subjected to a thermal oxidation and deoxidation treatment to remove a predetermined thickness of silicon in order to increase the mechanical strength of the piece. This method is characterized in that the thermal oxidation and deoxidation treatment is carried out in several steps, each step including a thermal oxidation phase followed by a deoxidation phase.

A timepiece includes a mechanical oscillator, formed by a balance and a piezoelectric balance spring, and a control device for controlling the frequency of the mechanical oscillator. This control device is arranged to be capable of generating time-separated control pulses, each including a momentary decrease in an electrical resistance applied by the control device between two electrodes of the piezoelectric balance spring relative to a nominal electrical resistance. The control device is arranged to be capable of applying a plurality of control pulses during each time of a series of distinct correction times or without interruption in a continuous time window, in order to respectively synchronize the mechanical oscillator at a correction frequency whose value depends on a detected positive or negative temporal drift or at a desired frequency for the mechanical oscillator.

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.

The method for manufacturing a timepiece component is capable of thermocompensating a functional assembly including the timepiece component. The method includes at least the following actions: a) providing (e1) a substrate (1) of semiconductor or metallic material; b) proceeding with the deposition (e2) of a polycrystalline or monocrystalline silicon layer (5) on the substrate (1); c) releasing (e4) the timepiece component (10) from the substrate (1).