Abstract: The invention relates to a double balance spring (21) including, made in a layer of silicon-based material (11), a first balance spring (23) coaxially mounted on a collet (13, 27), the collet (13, 27) including an extending part (9) that projects from said balance spring and which is made in a second layer of silicon-based material (5). According to the invention, said extending part extends (17) into a third layer (7) of silicon-based material coaxially with a second balance spring (25) so as to form a one-piece double balance spring (21) made of silicon-based materials. The invention also relates to a timepiece including a balance spring of this type and the method of manufacturing the same. The invention concerns the field of timepiece movements.

Abstract: Method of regulating the frequency of a resonator mechanism around its natural frequency, this mechanism including an elastic return means with a balance spring or a torsion wire, wherein a regulator device acts on this resonator mechanism with a periodic motion, with a regulation frequency which is comprised between 0.9 times and 1.1 times the value of an integer multiple between 2 and 10 of this natural frequency, controlling a periodic variation in the real part and/or the imaginary part of the rigidity of this elastic return means, this method being applied to a timepiece movement comprising a resonator mechanism of this type and including a regulator device arranged to control a periodic variation in the rigidity of this elastic return means.

Abstract: A resonator includes a balance spring formed in a single crystal quartz with crystallographic axes x, y, z, where the x axis is an electrical axis and the y axis is a mechanical axis, and cooperating with a balance. A thermal expansion coefficient of the balance is comprised between +6 ppm.° C.?1 and +9.9 ppm.° C.?1 and a cut angle of the balance spring to the z axis of the single crystal quartz is comprised between ?5° and +5°, so as to match the balance to the balance spring.

Abstract: The invention relates to a resonator comprising a balance spring formed in a single crystal quartz with crystallographic axes x, y, z, where the x axis is the electrical axis and the y axis is the mechanical axis, and cooperating with a balance. According to the invention, the thermal expansion coefficient of the balance is comprised between +6 ppm.° C?1 and +9.9 ppm.° C?1 and the cut angle of the balance spring to the z axis of said single crystal quartz is comprised between ?5° and +5°, so as to match the balance to the balance spring. The invention concerns the field of timepieces.

Abstract: An object of the present invention is to provide a method for producing a display device by which a substrate is thinned efficiently. Onto one original substrate having an area for a plurality of display devices, the other original substrate is bonded via a sealing resin layer, the pair of bonded original substrates is divided and separated into a plurality of pairs of substrates of a size of each individual display device, and thereafter a substrate thinning process of thinning the substrates is performed in a state where the substrates are held by substrate holding means.

Abstract: An oscillating device has an electro-mechanical drive, a pivotal or oscillating armature and a regulating circuit, wherein a capacitor, the capacitance of which varies with oscillation of the armature is used as a displacement transducer or pickup. A signal generated by a signal generator is conducted by way of the series-connection of the displacement transducer, a rectifier and a filter to an amplifier circuit, the frequency of said signal being much greater than the natural resonant frequency of oscillation of the electro-mechanical drive. An output voltage which is substantially in phase with the angular movements of the armature i.e. angle-proportional thereto, appears at the output of the amplifier circuit and is supplied to a set value input of a differential amplifier contained in the regulating circuit.

Abstract: A step motor comprising a stator made by bending a bar-shaped and magnetically highly permeable material into a substantially U-shape which is straight in one leg and curved in the other leg so that the magnetic flux distribution accompanying the curved leg will have a single ridge and the nearest and second nearest distances g.sub.1 and g.sub.2 of the curved leg from a rotor and the distance g.sub.3 between the straight leg and the rotor will maintain such relations as 1.2.ltoreq.g.sub.2 /g.sub.1 .ltoreq.1.8 and 2.1.ltoreq.g.sub.3 /g.sub.1 .ltoreq.3.5, the stator being secured to a main plate as inserted at the curved leg partly into a groove made in the main plate. A part of the curved leg defining the distance g.sub.1 is made to be a tip end part of the curved leg, the width at a part of the groove in which the tip end part of the curved leg is inserted to be secured to the main plate is made to be of the stator width and the groove width at other parts is made comparatively larger than the stator width.

Abstract: A timepiece including a mechanical movement is disclosed and a movable system for driving the movement. The movable system includes a balance wheel formed by a pair of plates and a magnetic member mounted on each plate. The magnetic members include a magnetic north and south pole arranged to provide a magnetic field. A coil is disposed in position so that its winding may be swept with the magnetic field which induces a voltage to which a circuit is responsive to develop a feedback signal to be applied across the winding to add energy to the movable system in replacement of energy losses of friction, and so forth. A feedback signal is developed if the movable system is sweeping the coil briskly. If movement of the movable system is not brisk, or the movable system has stopped, then a start pulse is developed for self-starting. The start pulse is normally prevented by the feedback signal which also serves as a reset signal to reset a start signal counter before completion of a counting operation.