Abstract: The invention relates mainly to a hairspring intended to equip the balance wheel of a mechanical timepiece. It is in the form of a spiraled rod (10) cut from an {001} single-crystal silicon plate. Its structure and its dimensions are calculated so as to minimize the thermal drift of the hairspring/balance-wheel assembly by means of the first and second thermal coefficients of its spring constant.

Abstract: The anti-trip device is for a detent escapement mounted on a wristwatch. It includes a finger fixed to the arm of the balance, two columns between which the finger can pass, said columns being secured to the balance bridge, and a locking arm fixed to the outer coil of the balance spring, said locking arm being able to be inserted between said columns and said finger to prevent the balance from rotating beyond an angle exceeding its normal operating angle. The locking arm is a clamp hooked onto the outer coil of the balance spring.

Abstract: In order particularly to put a watch into beat and adjust the isochronism, in addition to the poising screws (2a, 2b) of the balance (1) and the fine adjusting screw (7) pressing on the index tail 20a to alter the orientation of the index (20), the device includes, on the one hand, two screws (19, 29) respectively fixed in the balance cock (10) and in the index (20) to maneuver clamps by means of L-shaped rocking elements (13, 23) to fix the end of the balance spring and define its useful length, and on the other hand, a screw (9) for immobilizing the index (20) in a determined position, these three screws (9, 19, 29) enabling a fine adjustment to be carried out.

Abstract: A precision regulating device for the regulator pointer of a timepiece includes a balance cock and an index regulator mounted on the balance cock such that the index regulator is pivotable about a regulator axis. A hairspring key arranged on the index regulator at a radial distance from the regulator axis allows changing the active length of a hairspring of the oscillating system of the timepiece in response to pivoting of the index regulator. The index regulator also includes a radially directed regulator pointer. A counterpressure spring including a resilient arm has one end region fastened on the balance cock and another free end region arranged so that it forces the regulator pointer, under prestressing, in the pivoting direction and holds it in abutment against a regulating screw arranged in a rotatable manner in a threaded bore of the balance cock or a component connected to the balance cock.

Abstract: A spiral spring for use in connection with horology instruments is disclosed which includes a spiral spring and a collet which are produced in one piece without molecular discontinuity.

Abstract: A mainspring used as a power source for a driving mechanism is made of an amorphous metal sheet, and has an S-shaped free-exploded shape. The curvature changing point, where the curving direction of the free-exploded shape changes is formed on the inner end side of a middle point between the inner end on the winding side and the outer end serving as the other end of the inner end. Because of the high tensile stress and a low Young's modulus, the amorphous metal permits increase in mechanical energy stored in the mainspring.

Abstract: A mainspring used as a power source for a driving mechanism is made of an amorphous metal sheet, and has an S-shaped free-exploded shape. The curvature changing point where the curving direction of the free-exploded shape changes is formed on the inner end side of a middle point between the inner end on the winding side and the outer end serving as the other end of the inner end. Because of the high tensile stress and a low Young's modulus, the amorphous metal permits increase in mechanical energy stored in the mainspring.

Abstract: A mechanical timepiece movement has a mainspring serving as a power source, a wheel train rotated by a rotational force produced by the mainspring for driving a display, and an escapement and speed control apparatus for controlling rotation of the wheel train and having a balance with hairspring, an escape wheel and pinion and a pallet fork. A stud holder is rotatably mounted with respect to a central axis of the balance with hairspring and a hairspring holder is attached to the stud holder to undergo movement in a direction orthogonal to the central axis of the balance with hairspring. A hairspring has a central portion fixed to the balance with hairspring and an outer portion fixed to the hairspring holder. The hairspring is adjustable by pivoting the hairspring holder.

Abstract: According to a rate adjusting method, the movement of a mechanical timepiece is first assembled. The assembled movement is then disposed in a vertical position, and the rate is measured with respect to a plurality of vertical positions. On the basis of the result of this rate measurement, the magnitude and direction of the positional difference vector are calculated. On the basis of the result of this calculaton, the amount of weight to be added to or subtracted from the annular balance of the movement is calculated and the positions on the annular balance where this amount of weight is to be added to or to be subtracted from is calculated. Based on the results of these calculations, the amount of weight is added to or subtracted from the annular balance at the calculated positions.

Abstract: A mechanical time piece has a mainspring for generating a rotational force and a front train wheel for undergoing rotation in accordance with a rotational force generated by the mainspring. An escapement and speed control apparatus controls rotation of the front train wheel and has a timed annular balance for undergoing reciprocal rotational movement, an escape wheel and pinion for undergoing rotation in accordance with rotation of the front train wheel, and a pallet fork for controlling rotation of the escape wheel and pinion in accordance with rotational movement of the timed annular balance. A switch mechanism outputs an ON signal when a rotational angle of the timed annular balance becomes equal to or larger than a predetermined threshold angle and outputs an OFF signal when the rotational angle of the timed annular balance does not exceed the threshold angle.

Abstract: A mechanical timepiece has a mainspring for generating a rotational force and a front train wheel for undergoing rotation in accordance with a rotational force generated by the mainspring. An escapement/speed-control device for controlling rotation of the front train wheel has a balance with hairspring for undergoing reciprocal rotational movement, an escape wheel and pinion for undergoing rotation in accordance with rotation of the front train wheel, and a pallet fork for controlling rotation of the escape wheel and pinion in accordance with rotation of the balance with hairspring. A switch mechanism outputs an ON signal when a rotation angle of the balance with hairspring becomes a predetermined threshold angle or greater and outputs an OFF signal when the rotation angle of the balance with hairspring does not exceed the predetermined threshold angle. A position-detecting device detects a position of the mechanical timepiece.

Abstract: To provide a hairspring main body having small variation in spring property even in an inclined state by enabling to minimize individual difference and difficult to undergo influence of static electricity or external magnetic field, a hairspring structure capable of being easily integrated accurately in a state of restraining individual difference to a minimum, a speed control mechanism having small variation in a property caused by an inclined state or individual difference and a movement using the same. A hairspring structure of a speed control mechanism of a movement includes a hairspring main body made of carbon nanofiber and a hairspring attaching portion made of carbon nanofiber integrally molded with the main body, coupled to one end portion of the main body and substantially rigid.

Abstract: A mechanical timepiece has a power source comprised of a mainspring for undergoing rewinding movement to generate a rotational force. A front train wheel undergoes rotation in accordance with a rotational force generated during rewinding movement of the mainspring. An escapement/speed-control device controls rotation of the front train wheel. The escapement/speed-control device has a balance with a hairspring for undergoing alternately repeating rotational movement in left and right directions. An escape wheel and pinion undergoes rotation in accordance with rotation of the front train wheel. A pallet fork controls rotation of the escape wheel and pinion in accordance with rotational movement of the balance. A switch mechanism outputs an ON signal when a rotation angle of the balance reaches a predetermined threshold angle or greater, outputs an OFF signal when the rotation angle of the balance does not exceed the predetermined threshold angle.

Abstract: A method for manufacturing a balance-spring for a clockwork movement wherein a spring is formed by winding, from a wire or metal strip, said spring including an inner end intended to be fixed to a balance and a outer end zone intended to be fixed to the balance-spring stud and wherein the whole spring is subjected to a first heat treatment subsequent to the winding step of said wire. The method of the invention is characterized in that it further includes an additional step consisting in subjecting at least said outer end zone to a second heat treatment.This method improves in particular the shock resistance of the balance-spring.