EP1805565B1 - Wristwatch regulating member and mechanical movement comprising one such regulating member - Google Patents

Abstract

The regulating unit has a balance (3) connected to a movable permanent magnet (30) that oscillates along a circular path around a rotational axis of the balance. Fixed permanent magnets (40) generate magnetic field to return the balance to a stable equilibrium position. An escapement maintains movement of the balance around the equilibrium position, where movement of the balance is constituted by oscillations around the axis. An independent claim is also included for a mechanical movement for a wristwatch including a regulating unit.

Description

The present invention relates to a regulating organ for a wristwatch, and a mechanical movement for a wristwatch provided with such a movement.

The usual mechanical watches comprise an energy accumulator constituted by a barrel, a kinematic chain, or a train, driving needles, a regulating organ determining the running of the watch, and an escapement for transmitting the oscillations of the regulating organ. at the wheel. The present invention relates in particular to the regulating organ.

The conventional regulating members most often comprise a rocker mounted on a rotating axis and a return member exerting a torque on the balance to bring it back to an equilibrium position. The escapement, or drive member, maintains oscillations of the balance around the equilibrium position. The return member generally comprises a spiral spring, often called spiral, mounted coaxially with the balance. The hairspring transmits a restoring torque to the balance wheel through the ferrule; the rest position of the spiral spring determines the return position of the balance.

This widespread provision, however, has certain disadvantages.

First, the deformation of material at each oscillation of the spiral spring causes a loss of energy, and therefore a reduction in the running time of the watch. On the other hand, the precision of the watch depends to a large extent on the properties of the material used for the spiral spring, as well as the machining accuracy of the end curves. Despite significant progress in metallurgy, the reproducibility of these properties is difficult to guarantee. Moreover, the spiral springs tend to getting tired over time, so that the restoring force decreases with the aging of the watch, resulting in a variation in accuracy.

Moreover, the oscillations of the balance in one direction, for example in the clockwise direction, tend to unroll the spiral spring while the rotations in the opposite direction have the effect of contracting it. The deformation of the spring is therefore exerted differently depending on the direction of rotation of the balance, which influences the return force and therefore the accuracy and reproducibility.

The peg and the ferrule to fix the hairspring to the cock (or balance bridge), respectively to the pendulum, are other sources of disturbance and unbalance that unbalance the pendulum. On the other hand, the hairspring exerts a torsion torque on the balance at the point of attachment of the ferrule, which negatively influences the accuracy obtained. In a vertical position, the hairspring also tends to deform under its own weight, which causes a shift in its center of gravity and a disturbance of the period.

On the other hand, the balance is also subject to gravitational attraction as well as acceleration caused by the movements of the wearer. Since the spring force of the spiral spring is small, these external disturbances have an important influence on the accuracy of the gait, and complex correction mechanisms, for example vortices or even three-axis vortices, are sometimes used to compensate for them.

Then, the thickness of the spiral is added to that of the balance, so that the total thickness of the regulating member is relatively large.

Regulating organs for a wristwatch using a vibrating tuning fork have been devised, which make it possible to solve a certain number of the problems mentioned. These regulating members, however, also act by deformation and elastic vibration of material in the branches of the tuning fork, so that the accuracy also depends on the metallurgy and machining precision. These solutions have not been widely adopted.

Regulating organs of very varied constructions have also been imagined in clocks, clocks, or other large-scale horological devices. The volume available, and the fixed vertical position, allow for example to use the gravitational force to recall a pendulum, or pendulum, to its equilibrium position. The miniaturization and the major accelerations imposed on the usual mechanical watch movements dissuade the watchmakers from transposing the solutions used for clocks or clocks to movements for wristwatches.

An object of the present invention is therefore to provide a regulating organ for a different wristwatch and which avoids the disadvantages of the prior art.

Another object is to provide a regulating member that can be used with a mechanical watch, devoid of power source.

Another object of the invention is to provide a regulating device with a pendulum for a mechanical watch which is devoid of a cock, stud, ferrule and other means for fixing the return member to the balance wheel and to the axis of the balance wheel .

According to the invention, these steps are achieved by means of a regulating member having the features of the main claim, withpreferred variants being indicated in the dependent claims.

These aims are achieved in particular by means of a regulating member as defined in claim 1.

This arrangement has the advantage of allowing the complete removal of the spiral spring in mechanical watches, and of most of the problems associated with it.

This arrangement also has the advantage of offering greater precision, as well as less influence to disturbances caused by gravitation or by external accelerations.

In a variant, the return member tends to return the balance to at least one stable equilibrium position, the drive member, for example an exhaust, tends to remove it.

Oscillating members employing magnetic fields are described in particular US4'266'291 , US3'921'386 , US3'714'773 , US3'665'699 , US3'161'012 , de2424212 , and GB1444627 . Cessept documents however relate to electric watches, in which a magnetic field is generated by means of an electromagnet. These solutions are therefore not suitable for mechanical watches devoid of power source.

The additional document US2003 / 0137901 describes a mechanical watch movement in which the balance is provided with permanent magnets. The rotating field caused by the pendulum oscillations is detected by a gait control mechanism to control the variations in the pendulum oscillations. These oscillations are however caused by a conventional spiral spring, with all the drawbacks mentioned above.

The document US 3937001 discloses a watch having a mechanical power source and a regulating member having a balance provided with permanent magnets.

The frequency of the pendulum is controlled electrically by means of an electromagnet powered by a control circuit.

The document is also known GB 1389 293 which shows ( figures 10 and 11 ) a permanent magnet fixed on the plate and cooperating with a permanent magnet shown on the balance. However, the permanent magnet fixed on the plate does not exert the function of return member.

In a preferred variant of the invention, the magnetic field generated by the fixed part of the return member is fixed and constant, that is to say that it is not a current and that it does not vary in the time.

In a preferred variant, the magnetic field generated by the mobile magnet (s) is rotating; that is to say that the balance has an axis of rotation and that the mobile magnet or magnets, integral with the balance on which they are directly fixed, oscillate along a path circular around said axis of rotation. This reduces the number of moving parts and avoids translational movements that generate greater friction. In addition, all of the kinematic energy of the mobile magnets is transmitted to the balance. In addition, the movements of rotation of the balance can be transmitted by means of a conventional exhaust to the rest of the watch. The movement of the balance is thus constituted by oscillations around the axis of rotation of the balance, the amplitude of the oscillations being less than 360 °, for example less than 180 °, or even less than 120 °. It is thus possible to obtain a high frequency of oscillation, favorable to the precision and the resolution of the regulating organ; in addition, it is easier to obtain a relationship without discontinuities between the restoring force and the angular position of the balance when it oscillates in a limited range. The invention is however not limited to particular oscillation amplitudes; oscillation amplitudes between 180 and 300 °, or even amplitudes close to 360 °, may also be employed, for example by employing a single fixed magnet and a single movable magnet. These oscillations of greater amplitude have the advantage of minimizing the impact of the disturbance introduced by the exhaust at each cycle.

Preferably, at least one movable magnet oscillates in a circular path between two fixed permanent magnets arranged on a circular arc and spaced angularly by less than 180 °. By thus bringing the fixed permanent magnets together, a large magnetic interaction is created whose intensity varies according to a continuous function along the oscillation trajectory.

In a preferred embodiment of the invention, the balance is excited by mechanical elements to oscillate isochronously around the equilibrium position. Advantageously, the balance can thus be associated with a conventional escapement for a mechanical watch. Alternatively, the energy required for the excitation of the balance can be transmitted from the exhaust through permanent magnets Thus the magnetic balance of the invention can be used in a purely mechanical watch, without coils, electromagnets and power supply.

In a preferred embodiment, the mobile magnet or magnets are fixed relative to the balance, which facilitates the construction. The pendulum and the magnets oscillate according to the same alternating circular movement.

The fixed magnets preferably act to repel the moving magnets mounted on the balance. The position of equilibrium is determined by repulsion forces, and is reached when the mobile magnets are equidistant between two fixed magnets, and the repulsive force of the two fixed magnets acting on each moving magnet is compensated. Thus, the magnetic field generated by the fixed magnets is minimal at the equilibrium position, so that the amount of energy required to move the balance from this equilibrium position and to maintain an oscillation is reduced. The magnetic interaction between the fixed and movable magnets increases as the balance moves away from the equilibrium position, so that the return force increases proportionally with the angular distance of the balance relative to its rest position.

The stability of the equilibrium point can however be controlled by additional magnets acting by attraction. Likewise, the balance can be moved away from positions of undesired equilibrium

The invention does not exclude variants in which the equilibrium position is determined by attraction forces, and is reached when the moving magnets are at a minimum distance from corresponding magnets, or equidistant between two fixed magnets, attraction offset each other. However, this variant has the disadvantage of requiring a greater excitation to oscillate the balance around a position of equilibrium corresponding to a maximum of the magnetic attraction.

In a variant, the magnetized parts are constituted by magnetized portions of the balance itself. The pendulum could thus be constituted by a magnetized ring with alternating polarities along the periphery.

In another variant, the moving magnets are directly mounted on or connected to the anchor of the exhaust. The anchor then constitutes a pendulum, that is to say an oscillating element isochronically in a magnetic field.

• La figure 1a une vue de dessus schématique d'une première variante d'organe réglant selon l'invention.
• La figure 1b une vue de dessus schématique d'une première variante d'organe réglant selon l'invention, le balancier étant dans la position d'équilibre définie par les aimants.
• La figure 2 une vue en coupe de l'organe réglant selon la première variante de l'invention, comprenant danscet exemple deux paliers magnétiques et un blindage magnétique.
• La figure 3 une vue de dessusd'une variante d'organe réglant selon l'invention, comprenant desaimantsfixeset des aimants mobiles constitués chacun de deux aimants bipolaires accolés en opposition.
• La figure 4 une vue de dessus d'une variante d'organe réglant selon l'invention, comprenant des aimants fixes constitués chacun de deux aimantsbipolairesaccolésen opposition, et des aimants mobiles constitués chacun d'un seul aimant bipolaire.
• La figure 5 une vue de dessusd'une variante d'organe réglant selon l'invention, comprenant des aimants supplémentaires pour augmenter localement la stabilité du point d'équilibre.
• La figure 6 une vue de dessus d'une variante d'organe réglant selon l'invention, comprenant un balancier droit pivotant autour d'un axe central.
• La figure 7 une vue de dessusd'une variante d'organe réglant selon l'invention, comprenant un balancier droit pivotant autour d'un axe décentré.
• La figure 8 une vue de dessusd'une variante d'organe réglant selon l'invention, comprenant quatre aimants mobiles sur le balancier et quatre aimantsfixes.
• La figure 9 une vue de dessusd'une variante d'organe réglant selon l'invention, comprenant deux aimants mobiles sur le balancier et quatre aimants fixes.
• La figure 10 une vue de dessusd'une variante d'organe réglant selon l'invention, comprenant quatre aimants mobiles sur le balancier et deux aimants fixes.
• La figure 11 une vue de dessusd'une variante d'organe réglant selon l'invention, comprenant un élément torique dans lequel un aimant mobile est repoussé vers une position d'équilibre par un aimant fixe.
• La figure 12 une vue de dessusd'une variante d'organe réglant selon l'invention, comprenant un cylindre fermé à sesextrémitéspar deux aimants fixes, ainsi qu'un aimant mobile repoussé en position intermédiaire par lesdeux aimants fixes.
• La figure 13 une vue en perspective d'une variante d'organe réglant selon l'invention dans laquelle lesaimants mobiles liés au balancier et les aimants fixes sont superposés, dans deux plans parallèles, l'organe réglant étant en position d'équilibre.
• La figure 14 une vue en perspective de l'organe réglant de la figure 13, oscillant dansune position intermédiaire.
• La figure 15 une vue de dessusd'une variante d'organe réglant selon l'invention, dans laquelle les aimants mobiles sont directement montés sur l'ancre qui agit ainsi comme balancier.
• La figure 16 une vue de dessusd'une variante d'organe réglant selon l'invention, dans laquelle les aimants mobiles sont directement montés sur l'ancre qui agit ainsi comme balancier, lesaimantsfixesétant superposé aux aimants mobiles dans un plan parallèle.
• La figure 17 une vue de dessusd'une variante d'organe réglant selon l'invention, dans laquelle lesaimantsfixesont une forme particulière destinée à garantir une force de rappel proportionnelle à la distance angulaire, et dans laquelle le balancier a la forme d'une tige.
• La figure 18 une coupe transversale de l'organe réglant de la figure 17 dans le plan de la tige.
• La figure 19 une vue de dessusd'une autre variante d'organe réglant dans laquelle la force de rappel est proportionnelle à la distance angulaire.
• La figure 20 une vue de dessusd'une autre variante d'organe réglant dans laquelle la force de rappel est proportionnelle à la distance angulaire, cette variante employant un anneau magnétique avec une magnétisation variant le long de la périphérie.
• La figure 21 une vue en coupe d'une variante d'organe réglant selon l'invention comportant desaimantsd'épaisseur variable radialement.
• La figure 22 une vue de dessusd'une variante d'organe réglant selon l'invention, correspondant à la première variante mais dans laquelle un capteur et un circuit permettent de déterminer et/ou contrôler l'amplitude des oscillations du balancier.
• La figure 23 une vue de dessusd'une variante d'organe réglant selon l'invention, correspondant à la première variante maisdans laquelle une bobine génère un courant dont la fréquence dépend de la fréquence d'oscillation du balancier.

The invention will be better understood on reading the examples of embodiments illustrated by the appended figures which show:

• The figure 1a a schematic top view of a first variant of regulating member according to the invention.
• The figure 1b a schematic top view of a first variant of the regulating member according to the invention, the balance being in the equilibrium position defined by the magnets.
• The figure 2 a sectional view of the regulating member according to the first variant of the invention, comprising in this example two magnetic bearings and a magnetic shielding.
• The figure 3 a top view of a variant of a regulating member according to the invention, comprisingfixesmagnetsand mobile magnets each consisting of two bipolar magnets contiguous in opposition.
• The figure 4 a top view of a variant of regulating organ according to the invention, comprising fixed magnets each consisting of two magnetsbipolairesaccolésen opposition, and movable magnets each consisting of a single bipolar magnet.
• The figure 5 a top view of an alternative regulating member according to the invention, comprising additional magnets for locally increasing the stability of the equilibrium point.
• The figure 6 a top view of an alternative regulating member according to the invention, comprising a right rocker pivoting about a central axis.
• The figure 7 a top view of an alternative regulating member according to the invention, comprising a right rocker pivoting about an off-axis.
• The figure 8 a top view of a variant of regulating organ according to the invention, comprising four movable magnets on the balance and four fixed magnets.
• The figure 9 a top view of a variant of the regulating organ according to the invention, comprising two movable magnets on the balance and four fixed magnets.
• The figure 10 a top view of a variant of regulating organ according to the invention, comprising four movable magnets on the balance and two fixed magnets.
• The figure 11 a top view of a variant of regulating member according to the invention, comprising a toroidal element in which a movable magnet is pushed back to an equilibrium position by a fixed magnet.
• The figure 12 a top view of a variant of the regulating member according to the invention, comprising a cylinder closed at its ends by two fixed magnets, and a movable magnet pushed in the intermediate position by the two fixed magnets.
• The figure 13 a perspective view of a variant of a regulating member according to the invention in which the mobile magnets linked to the balance and the fixed magnets are superimposed in two parallel planes, the regulating member being in equilibrium position.
• The figure 14 a perspective view of the regulating organ of the figure 13 oscillating in an intermediate position.
• The figure 15 a top view of a variant of regulating organ according to the invention, wherein the moving magnets are directly mounted on the anchor which acts as a rocker.
• The figure 16 a top view of a variant of the regulating organ according to the invention, in which the moving magnets are directly mounted on the anchor which acts as a rocker, the fixed magnets being superimposed on the moving magnets in a parallel plane.
• The figure 17 a top view of a variant of a regulating member according to the invention, in which the fixed magnets have a particular shape intended to guarantee a restoring force proportional to the angular distance, and in which the balance has the shape of a rod.
• The figure 18 a cross section of the regulating organ of the figure 17 in the plane of the stem.
• The figure 19 a view from above of another variant of regulating organ in which the restoring force is proportional to the angular distance.
• The figure 20 a view from above of another variant of a regulating member in which the restoring force is proportional to the angular distance, this variant employing a magnetic ring with a magnetization varying along the periphery.
• The figure 21 a cross-sectional view of a variant of a regulating member according to the invention comprising magnets of variable thickness radially.
• The figure 22 a top view of an alternative regulating member according to the invention, corresponding to the first variant but in which a sensor and a circuit for determining and / or controlling the amplitude of the pendulum oscillations.
• The figure 23 a top view of an alternative regulating member according to the invention, corresponding to the first variant but in which a coil generates a current whose frequency depends on the oscillation frequency of the balance.

In the following description and in the claims, the adjective "fixed" always refers to the motion. An element is fixed if it does not move relative to the movement, for example with respect to the movement stage.

The term "pendulum" designates an oscillating piece under the effect of an excitation around a position of equilibrium. The substantially isochronic oscillations determine the progress of the watch. The balance can be constituted by a wheel with any number of spokes, a disc, a rod, an anchor, etc.

The figure 1b schematically illustrates a regulating member 1 comprising a rocker 3 oscillating about an axis 300 perpendicular to the plate of the movement. In this example, the balance 3 comprises an annular serge and has two radial spokes (or arms) 302 about the axis 300. Screws 301 can easily move the moment of inertia of the balance. The pendulum constitutes a mass of inertia; its mass, as well as its radius, are preferably important within the limits imposed by the will of miniaturization of the movement. The large restoring force that the claimed solution allows allows the use of particularly important weights of inertia.

Bimetallic rockers that deform to compensate for temperature variations are also possible in the context of the invention. Other means can be implemented to compensate for the variation of the intensity of the magnetic field related to the temperature.

The balance 3 is connected to or provided with mobile permanent magnets 30 driven in rotation with the balance. The illustrated example comprises two discrete permanent bipolar magnets which are arranged asymmetrically with respect to the axis 300, at 180 ° to one another. Each magnet has a positive pole and a negative pole equidistant from the axis 300. The magnets 30 can be held mechanically or by sticking on the balance 3. As indicated, the magnetized parts could also be constituted by magnified parts of the balance itself, or by a magnetic track on the balance. The pendulum could thus be constituted by a magnetized ring with alternating polarities along the periphery. The pendulum could for example be magnetized homogeneously or gradually by means of a recording head, that is to say a coil generating a magnetic field of controlled intensity in a gap.

The regulating member further comprises two fixed permanent magnets 40, mounted on a bridge or on the stage of the movement by any suitable means. The two magnets are arranged in the plane of the balance 3, symmetrically and at 180 ° with respect to the axis 300. In a variant not shown, the fixed magnets 40 could also be arranged in another plane, parallel to the plane of the balance 3. The magnets 40 each comprise a positive pole and a negative pole whose arrangement, symmetrical with respect to the axis 300, is, however, reversed with respect to the arrangement of the poles on the moving magnets 30. Thus, the stationary magnets 40 and mobiles 30 repel with each other. a maximum magnetic interaction force when they are close. The equilibrium position is reached by turning the balance by 90 °, so as to push each movable magnet 30 equidistant from two fixed magnets40; the magnetic field generated by the permanent magnets 40 is minimal in this arrangement, so that the force or moment necessary to leave this equilibrium position is also reduced.

The magnets 30 and 40 are preferably chosen so that the magnetic repulsion force, even in the equilibrium position illustrated, is much greater than the gravitational force exerted on the balance 3. Permanent magnets composed of metal oxides , rare earth compounds or platinum-cobalt alloys will preferably be used to obtain large residual fields.

The position of the fixed magnets, or even the position of the movable magnets, may in all variants be adjusted, for example by means of screws, in order to adjust the oscillation frequency of the balance.

Oscillations of the balance thus depend little on the inclination of the balance. The rotating mass of the balance 3 (including the screws 301) and moving magnets 30 is furthermore preferably distributed as evenly as possible around the axis 300, so as to improve the balance of the balance.

In all the embodiments, additional mechanical stops, not shown, can be provided on the balance 3 and / or on a bridge in order to limit the amplitude of the possible rotations of the balance, and thus prevent the balance from moving position of balance to another following a shock, for example. Similar abutment elements may also be employed with the other embodiments discussed below. The additional stops may for example comprise elastic means for damping shocks at the end of the race.

The balance 3 is swinging around the equilibrium position of the figure 1b by means of a drive member constituted in this example by an escapement 2, here a conventional Swiss anchor escapement. The escapement can also be specially adapted to take into account the low oscillation amplitude of the balance.

An escape wheel 210 driven by the barrels (not shown) or by any suitable mechanical energy source actuates the anchor 20 through the rubis200 pallets. The movements of the anchor, limited by the stops 201 are transmitted to the balance 3 through the fork 202 and the pin 31.

Other types of exhausts, including electric or magnetic exhausts, may be used in the context of the invention. In a magnetic escapement, the pulses given to the balance 30 are preferably by attraction or repulsion between magnetized parts on the balance and on the exhaust. Uncontacted training is possible.

The amplitude and the frequency of the oscillations around the equilibrium position are determined by the force and disposition of the magnets, and by the amplitude of the torque transmitted by the drive member. It is also noted that the rocker 30 oscillates without material deformations, so that the oscillation frequency does not depend on the metallurgical characteristics or the aging of elastic parts.

The large restoring force that the use of powerful magnets makes it possible to obtain high oscillation frequencies, higher than the usual frequencies in the usual mechanical watches, and thus to increase the accuracy and / or the resolution of the movement. A choice of appropriate magnets and geometry thus makes it possible to display indications of time or duration with a resolution of the order of one tenth or even one hundredth of a second.

The regulating organ of the figure 1b is shown in partial section on the figure 2 , the exhaust 2 has been removed from the figure to improve readability. In the exemplary embodiment illustrated, the rocker 3 pivots about an axis 300 perpendicular to the upper bridge 41 and the lower bridge 42. The bridges 41 and 42 preferably form a magnetic shielding both to protect the balance 3 of the fields external magnets, and to protect the other components of the watch from the magnetic fields generated in particular by the magnets 30 and 40. A shielding may also, in a variant not shown, be obtained by means of elements distinct from the bridges, for example by means of the platinum, dial, box, or dedicated items. Shielding on all sides can also be adopted. It will also preferably use a movement of which at least some axes, gears, wheels and or bridges are made of non-magnetic materials. In a preferred embodiment, the kinematic chain between the regulating member and the needles comprises at least one element made of synthetic material, for example a belt driven by a pulley.

The axis 300 of the balance 3 is maintained in the bridges 41, 42 by means of two bearings 410 and 420, for example conventional bearing blocks, incabloc bearings or in the preferred example illustrated magnetic bearings In this example, the upper ends 3001 and lower 3002 of the axis 300 are magnetized or provided with magnets. The bearings 410 respectively 420 each comprise a housing 4100 respectively 4200 whose depth and diameter are slightly greater than the corresponding dimensions of the axis 300. The walls of the housings are magnetized with a polarization identical to that of the corresponding ends of the axis 300, so as to push this axis which is thus levitated between the bearings 410 and 420. The axis 300 can rotate without friction. This arrangement also makes it possible to eliminate the wear of the bearings 410, 420 and the axis 300.

The balance 3 of the invention can thus oscillate without any contact with other elements, being recalled to its equilibrium position by means of magnets 30,40, maintained by magnetic palms410, 420 and / or driven by a magnetic escapement. It is thus possible to reduce the friction and wear caused by the movements of the balance. These different measures can however be implemented independently of each other.

The figure 1a illustrates a variant of regulating organ similar to the variant of the figure 1b , but in which the realization of the escapement allows oscillation of the balance of greater amplitude, for example oscillations up to 180 °, see more by modifying the disposition of the magnets The exhaust is preferably an exhaust Swiss anchor that allows significant oscillations of the pendulum without generating excessive oscillations of the anchor. The balance 3 is further equipped with screws for correcting any unbalance, or other sources of disturbances of walking.

The geometry of the balance described in relation to figures 1a , 1b and 2 is similar to that of the rockers of the conventional mechanical regulating organs. The use of a magnetic return member, however, makes it possible to imagine constructions of 3 different balances, several examples of which will be described in relation to Figures 3 to 13 in particular.

The figure 3 illustrates in a simplified manner a second variant regulating member according to the invention (without the exhaust 2), wherein the fixed permanent magnets 40 and the moving permanent magnets 30 are each constituted by two magnets contiguous in opposition. The resulting magnetized piece thus has two ends provided with identical polarities.

The figure 4 illustrates in a simplified manner a third variant of the regulating member according to the invention, in which the fixed permanent magnets40 each consist of two magnetsaccolésen opposition. The resulting magnetized piece thus comprises two ends provided with identical polarities. The two movable magnets 30 on the balance 3 each consist however of a bipolar magnet, the assembly comprising a horizontal axis of symmetry.

The figure 5 illustrates in a simplified manner a fourth variant of the invention, corresponding to the figure 1 but in which additional fixed permanent magnets 47 are arranged facing moving magnets 30 at the equilibrium position. In the illustrated example, the fixed additional magnets 47 and the moving magnets 30 attract each other to the equilibrium position. The equilibrium position is thus determined both by the repulsion of magnets 30 and 40, and by the attraction of magnets 30 and 47; the contribution of the forces of repulsion is, however, preponderant, in order to limit the stability of the equilibrium point and to allow the system to oscillate even with a low drive energy. The magnetic field generated by the additional fixed magnets 47 is therefore preferably much smaller than the magnetic field of the magnets 40.

Additional magnets 47 with reversed poles, so as to reduce the stability of the equilibrium point, can also be devised within the scope of the invention.

Similar results can be obtained by placing additional permanent magnets on the balance.

Additional magnets may also be provided at the end of the race, either on a bridge or on the balance, so as to attract or push the balance in this position, and reduce the variation of the amplitude of the oscillations caused by disturbances.

The figure 6 illustrates in simplified manner a variant of the regulating member according to the invention, comprising a right rocker (in needle) 3 pivoting about a central axis 300. The two ends of the balance 3 are provided with magnets 30 pushed to the equilibrium position by the mounted magnets40 mounted on a bridge not shown. Although the mass of inertia of the balance 3 in this variant embodiment is greatly reduced, this arrangement reduces the size of the regulating member.

The figure 7 illustrates a top view of a variant of regulating member according to the invention, comprising a right balance 3 similar to that of the figure 6 , but pivoting about an axis 300 off-center. Only the end of the rocker 3 remote from the axis 300 is in this example provided with a magnet pushed towards the equilibrium position illustrated by means of two magnets 40.

In this variant, the exhaust could be obtained by extending the balance 3 by an anchor-shaped part directly actuated by the anchor wheel.

In addition to the straight rockers (needle, or I) desfigures6 and 7, T-shaped or H-shaped balances, for example, can easily be imagined.

The figure 8 illustrates a top view of a sixth variant of regulating member according to the invention. The regulating organ is similar to that of Figures 1 to 2 but includes four movable magnets 30 distributed at 90 ° to each other on the balance 3 and four fixed magnets 40 distributed at 90 ° to each other on a not shown bridge. This arrangement makes it possible in particular to reduce the distance between the stationary magnets and the moving magnets, while multiplying the number of magnets, so that the resulting magnetic interaction force, and thus the return torque, are increased.

Arrangements comprising more than four mobile magnets and / or more than four fixed magnets can also be imagined. Moreover, as mentioned, it is also possible to use magnetized parts with a plurality of zones of alternating magnetic polarities. An alternating magnetic field in all or nothing, or according to a sinusoidal function for example, may for example be written by a magnetic head on the periphery of the balance and / or on a fixed element related to the movement.

The figure 9 illustrates a top view of a variant of regulating organ in which the number of movable magnets 30 on the balance is less than the number of fixed magnets 40. Each moving magnet is thus subjected to the action of a pair of fixed magnets; each fixed magnet acts only on a single moving magnet. Arrangements comprising two fixed magnets and a single movable magnet can also be imagined

The figure 10 illustrates a top view of a variant of regulating organ in which the number of movable magnets 30 on the balance is greater than the number of fixed magnets40. Each moving magnet is thus subjected to the action of a single fixed magnet; however, each fixed magnet acts on two moving magnets.

The amplitude of the oscillations of the pendulum of the figure 9 is very limited, less than 90 °. It is thus possible to make it oscillate very quickly and to obtain a very fine resolution for the measurement of time. However, oscillations of small amplitude, very fast, have the disadvantage of amplifying the influence of the disturbances caused at each cycle by the friction with the anchor and the pendulum. According to the desired resolution and the quality of the realization of the escapement, it may therefore be desirable to increase the amplitude of the oscillations beyond 180 °, instead of trying to reduce it. For this purpose, arrangements with two movable magnets and a single fixed magnet are also possible, or even a single fixed magnet and a single movable magnet that can achieve oscillations of almost 360 °.

Furthermore, in a variant not illustrated, it is also possible to increase the rotational mass of inertia by linking the balance 3 with another oscillating mass through a kinematic chain, for example a gear on the axis the balance, or a belt. Oscillations of the balance are thus transmitted to an additional oscillating weight. Gear ratios between the rocker arm 3 and the additional oscillating mass also make it possible to obtain a different amplitude of oscillation on these two components. For example, it is conceivable to oscillate the balance 3 by 180 ° and to connect it kinematically through a gear of factor 8 to another rotating mass performing oscillations of 8 X 180 °, that is to say say four rounds, each cycle.

The figure 11 illustrates a variant of the invention in which the rocker is constituted by a movable magnet 30 whose path is constrained by a guide 43, for example a slide, a slide or a rail, in this example a toric slide. The arrangement of the poles of the fixed magnet 40 is opposed to the arrangement of the poles of the movable magnet 30, so that the equilibrium position is reached when the movable magnet is diametrically opposed to the fixed magnet. This provision allows to use a single moving magnet and a single fixed magnet. Different shapes of slides, rails or slides 43, non-annular, can also be imagined; moreover, the fixed magnet 40 could be out of the slide.

In this example, the rocker 30 is driven through the anchor 20 actuated by an unrepresented escape wheel and articulated about the axis 300. The anchor 20 extends the arm of the rocker out of the slide 43. A magnetic escapement can also be used in the context of the invention.

Arrangements of regulating members having a plurality of stable equilibrium positions may also be imagined within the scope of the invention.

The figure 12 illustrates a variant of the invention wherein the balance 3 is constituted by or comprises a magnet 3 linearly moving in a cylinder, a slide or along a rail 43 whose two ends are closed by fixed magnets 40. The polarities magnets 30 and 40 are arranged so that the magnetic interaction force tends to urge the moving magnet 30 levitated midway between the two fixed magnets 40, as illustrated in FIG. figure 12 . The balance 3 can be set oscillation by means of a member external to the rail 43 and following the movements of the balance 3 through a mechanical or magnetic link.

The movement of the pendulum in Figures 11 and 12 is constrained by the guides43, resulting in loss of energy and loss of accuracy in case of deformation or expansion of the guide surfaces. These variants, however, make it possible to implement unconventional solutions to meet particular needs.

Rockers oscillating in a plane according to two degrees of freedom, or even three degrees of freedom, can also be imagined within the scope of the invention. A plurality of permanent magnetsfixes In this case, they are intended to push the balance arm towards an equilibrium point around which a drive member makes it oscillate. The small thickness available in a wristwatch, and the difficulties of achieving the exhaust, however, make such solutions more difficult to apply.

The Figures 13 and 14 illustrate a variant of the regulating member comprising a movable magnet 30 constituted by a disk mounted in the center of the balance 3. The disc 30 comprises sectors, in the illustrated example two sectors, provided with alternating magnetic polarities. The fixed magnet 40 is mounted above the movable magnet 30, in a parallel plane, and also constituted by a disk provided with sectors of alternating polarity. In the equilibrium position illustrated on the figure 13 the balance is positioned so that the opposite polarity sectors of the two magnets 30 and 40 are exactly superimposed. The balance is brought into this position essentially by attraction of the opposite poles of the two magnets, and to a lesser extent by repulsion of the identical poles. The balance oscillates around this position of stable equilibrium when a disturbance is brought to it for example by the escapement not shown in the figure.

It is also possible to modify the arrangement of FIGS. 13 and 14, for example by employing magnets 30 and 40 provided with more than two sectors of alternating polarity, or employing several fixed magnets in a first plane and several magnets moving in a parallel plane. The moving magnets may also for example be placed on the periphery of the balance, and the magnets moving above these positions. It is also possible to use a number of different magnet magnets and moving magnets; for example, it is also possible in the context of the invention to mount the movable magnet 30 between a fixed magnet on an upper plane, as illustrated in the figures, and an additional fixed magnet, not shown, in a lower parallel plane.

The figure 15 illustrates a top view of a variant of a regulating member in which the moving magnets 30 are directly mounted on Anchor 20. Fixed anchors40 tend to repel and swing these movable magnets around a position of equilibrium. The anchor 20 thus acts as a pendulum. This variant, although conceivable, however, has the disadvantage of being more sensitive to shocks, the inertia of the anchor is generally insufficient to ensure isochronous oscillation. An anchor with high inertia would be possible, but would require a significant excitation energy to make it oscillate.

The variant of the figure 16 combines the features of the illustrated solutions on the Figures 13 and 15 , that is to say an anchor 20 itself acting as a pendulum and permanent and fixed magnetsconstitués by superimposed disks provided with alternating polarity sectors.

Ordinary mechanical magnets have a restoring force proportional to their elongation d: $$\mathrm{F}\mathrm{=}\mathrm{k}\mathrm{\cdot }\mathrm{d}$$

Applied to a spiral spring intended to bring a rocker to its stable rest position, this force guarantees an isochronic oscillation when the excitation of the rocker, caused by the escapement, obeys certain constraints.

The restoring force between two punctual magnetsdécroit on the other hand in a quadratic manner, or even cubic, when the spacing d between the magnets increases: $$\mathrm{F}\mathrm{\cong }\mathrm{j}\mathrm{/}{\mathrm{<figure-callout\; id="2"\; label="d"\; filenames="imgf0010.png"\; state="\{\{state\}\}">d</figure-callout>}}^{\mathrm{2}}\mathrm{or\; F}\mathrm{\cong }\mathrm{j}\mathrm{/}{\mathrm{<figure-callout\; id="3"\; label="d"\; filenames="imgf0003.png,imgf0004.png"\; state="\{\{state\}\}">d</figure-callout>}}^{\mathrm{3}}$$

Used with a conventional escapement, this relation guarantees a stable isochronic oscillation only when the oscillations satisfy very particular conditions (for example when their amplitude is small).

The variant of the figure 17 illustrates an example of a regulating organ in which the relationship between the beam spacing (ie its angular distance from the rest position) and the restoring force or torque obeys a different relationship.

For this, the volume of the fixed magnets 40 increases when, within the range of oscillations p, one moves away from the rest position by an angular distance d, so as to increase the reminder force at a distance of this position. The movable magnets 30 on the balance 3 are however of constant size along the trajectory of the oscillations. Mechanical or magnetic stops not shown can be provided to force the balance to remain in the oscillation range p even in case of shock for example.

Thus, the unrepresented escapement tends to rotate the balance in the antitemporal direction, which rotation is countered by the repulsion of the magnets.

In the example of the figure 17 the surface of the fixed magnets 40 in a plane parallel to the plane of the oscillations of the balance 3 increases inside the oscillation range p with the cube of the angular distance d, or possibly according to d ⁴ . The fixed magnets40 thus have the form of sectioned moons. Another possible arrangement is illustrated on the figure 19 , in which the balance oscillates around the axis 300 on each side of the rest position.

The mobile magnets30 of the figure 17 move in a circular path in a plane parallel to the plane of the fixed magnets40. However, it is also possible, in order to increase the magnetic interaction, to rotate the moving magnets between two parallel planes each provided with one or more fixed magnets 40. Conversely, it is also possible to provide a balance 3 composed of several superposed trays, rotating on the same axis and all provided with movable magnets 30; the different moving plates are then separated by a bridge or several bridges carrying fixed magnets. Other types of stackings of any number of moving magnet planes and fixed magnet planes can be imagined.

Other non-illustrated arrangements are possible to correct the relationship between the restoring force caused by the magnets 30, 40 and the distance or the angular distance of the balance 3 from the rest position. For example, instead of varying the surface Fixed magnets in the horizontal plane, it is possible to vary the surface of the moving magnets. On the other hand, it is also possible to modify the thickness of the fixed and / or mobile magnets, or their magnetization, along the path of the balance. These different measures can be combined with each other. Moreover, it is also possible to use magnets of variable volume or magnetization in a system comprising a circular balance with a large inertia, and / or to use an arbitrary number of fixed and / or mobile magnets of variable volume or density. Finally, a restoring force that varies according to the angular distance of the balance can also be obtained with discrete magnets of size, material, magnetization and / or

The figure 20 illustrates a variant of the invention in which the rocker 3 is provided with three spokes 302, at least one of which is magnetized with poles opposite to each radial end. Thus, only the outer pole of the beam exerts a strong interaction with the fixed magnets 40, which are constituted by a magnetic ring 40 with a polarization in one direction inside, and in the opposite direction on the outside. In addition, the magnetization of the fixed magnet 40 increases, preferably according to d ³ or possibly according to d ⁴ , with the angular distance d relative to the rest position d = 0 of the balance. The density of the magnetic field generated by the fixed magnet varies along the periphery of the beam so as to preferably provide a restoring force that varies linearly with the angular position of the balance. In a variant not illustrated, the pendulum could also be provided with a magnetic peripheral ring, or discrete magnets at the periphery, with a variable magnetization along the periphery.

The progressive magnetization of the fixed magnet can for example be obtained by magnetizing it by means of a recording head, as mentioned above. In case of saturation of the magnetic material, it may be necessary to limit the oscillations of the balance in the portion ensuring the desired relationship between the angular position of the beam and the restoring force. Moreover, instead of magnetizing the entire balance, it is conceivable to magnetize only a magnetic track attached to the latter, parallel or perpendicular to the plane of the balance.

An additional fixed permanent magnet 47 is disposed facing the movable magnet 30 at the maximum repulsion position, in order to prevent the balance from reaching and exceeding this position. This magnet 47 thus acts as a magnetic stop to move the balance from a position of undesired balance, without the disadvantages of mechanical stops causing shocks likely to disrupt the isochronic movement of the balance.

In the case of pendulum oscillations less than 180 °, it would also be possible and even better to provide magnetic stops 47 not shown closer to the limits of the balance of the balance, for example a stop at 10 o'clock and a second stop 2 hours to push the pendulum well before it reaches the unstable unstable equilibrium position at 12 o'clock.

On the variant of the figure 20 permanent magnets consist of a continuous ring. However, it is also possible to provide a discontinuous ring, for example provided with one or more air gaps or with discrete magnets.

On the variantsoffigures 17 to 20, the volume of fixed (and / or mobile) magnets thus varies continuously along the circular path of the balance, so as to control the relationship between the restoring force and the angular position of the balance.

The figure 21 illustrates a variant of the invention in which the thickness of the moving magnets 30 increases radially, while the thickness of the fixed magnets 40 decreases away from the axis of rotation 300. An inverted arrangement, ensuring a gap between the magnets fixed and mobile, can also be adopted. Moreover, the radial variation in thickness can also be combined with a variation along the periphery of the regulating member. The radial and / or circumferential thickness variation of the magnets 30, 40 can also be used with the embodiments of the Figures 13 and 14 having magnets superimposed. Moreover, it is also possible to vary the magnetization of the fixed and mobile magnets as a function of the distance to the center.

The figure 22 illustrates a variant of the regulating member illustrated in the Figures 1 to 2 and further comprising a plurality of electrodes 44, whose electrical property varies as a function of the electric field to which they are subjected. The electrodes 44 thus make it possible to detect or even to measure the rotating magnetic field generated by the oscillations of the moving magnets 30. The electrodes 44 may for example be constituted by magnetoresistive electrodes or by Hall sensors. They can be connected to each other and to an integrated circuit 46 through conductive tracks 440 according to different topologies. The circuit 440 makes it possible to determine the amplitude of the oscillations of the rocker 30 and / or the frequency of oscillation. The circuit 46 may be powered by an independent energy source, for example a battery, or by a coil generating an alternating current under the action of the displacements of the balance, as illustrated in connection with the figure 18 mentioned below. An electronic correction of the running of a mechanical watch can thus be obtained.

The measurement of the frequency and / or the amplitude of the oscillations of the balance 30 makes it possible, for example, to detect any irregularities in the operating frequency. This information can be used to correct the running of the watch, for example by exerting a correction torque on the balance 30 by means of unrepresented electromagnets or other electromechanical means, so as to correct the amplitude and the frequency of the oscillations. This information can also be used to display an end-of-march signal, so as to signal to the user that the progress of the watch becomes inaccurate.

The figure 23 illustrates a variant of the regulating member in which a coil 45 opposite each movable magnet 30 generates a current proportional to the magnetic field generated during the displacement of this magnet near the coil. Arrangements having two coils in phase opposition, or three coils generating a three-phase current system, can also be used. Illuminated coils generate an approximately sinusoidal current whose frequency corresponds to the oscillation frequency of the pendulum. This frequency can be measured by a circuit 45, for example by comparing it with a reference frequency provided by a quartz, for example to inform the user in case of irregular frequency and / or correct this frequency, for example by injecting a compensation current in the coil 45. The circuit 46 may comprise a rectifier and thus be powered itself by the current generated by the coil 45. The current generated by the coil can also be used to power a circuit providing any type of function that one wishes to bring to a mechanical watch without battery.

The regulating organ described can be used in a movement for a stand-alone wristwatch, or in an auxiliary module, for example a chronograph module, intended to be superimposed on a basic movement.

The different regulating members described all comprise at least one mobile permanent magnet and at least one fixed permanent magnet.

The regulating member of the invention is preferably mounted in a mechanical movement, preferably without a battery, and in a watch case revealing at least part of the pendulum, which allows the user to control his movements at all times

Claims (47)

1. Regulating member for mechanical wristwatch, having:

   a balance (3), linked to at least one mobile permanent magnet (30),

   a return member (30, 40) arranged for returning said balance towards at least one position of equilibrium,

   a driving element (2) arranged for maintaining the balance's movement around said position of equilibrium,

   characterized in that said return member has at least one fixed permanent magnet (40) arranged for generating a magnetic field in order to return said balance towards said position of equilibrium.
2. The regulating member of claim 1, wherein said balance has a rotation axle (300), said at least one mobile permanent magnet oscillating along a circular trajectory around said rotation axle.
3. The regulating member of one of the claims 1 to 2, wherein said fixed magnets are distributed on an arc of circle.
4. The regulating member of claim 3, wherein at least one said mobile magnet (30) is arranged for oscillating along a circular trajectory between two fixed magnets (40) spaced angularly by less than 180° on said arc of circle.
5. The regulating member of one of the claims 1 to 4, wherein said movement of the balance is constituted by oscillations around the balance's rotation axle, the amplitude of said oscillations being less than 180°.
6. The regulating member of one of the claims 1 to 4, wherein said movement of the balance is constituted by oscillations around the balance's rotation axle, the amplitude of said oscillations being greater than 180° and preferably less than 300°.
7. The regulating member of one of the claims 1 to 6, wherein said driving element (2) is constituted by an escapement to transmit the circular oscillations from the balance to the rest of the movement.
8. The regulating member of one of the claims 1 to 7, wherein said return member is arranged for acting on said balance (3) without matter deformation.
9. The regulating member of one of the claims 1 to 8, wherein said return member is arranged for acting without contact with said balance (3).
10. The regulating member of one of the claims 1 to 9, wherein said magnetic field is constant in time.
11. The regulating member of one of the claims 1 to 10, wherein at least one said fixed magnet (40) is placed so as to push back at least one said mobile magnet (30) towards said position of equilibrium.
12. The regulating member of one of the claims 1 to 11, wherein the magnetic interaction between said at least one fixed magnet (40) and said at least one mobile magnet (30) is minimal at said position of equilibrium.
13. The regulating member of one of the claims 1 to 12, wherein said position of equilibrium is determined by the action of at least two fixed magnets (40) acting on at least one same mobile magnet (30).
14. The regulating member of claim 13, wherein, at the position of equilibrium, the magnetic fields exerted by the two said fixed magnets (40) onto said at least one same mobile magnet (30) are of equal intensity.
15. The regulating member of one of the claims 13 or 14, wherein said mobile magnet (30) is at equidistance between two fixed magnets (40) at said position of equilibrium.
16. The regulating member of one of the claims 1 to 15, wherein said position of equilibrium is determined by the action of at least one fixed magnet (40) acting simultaneously on at least two mobile magnets (30).
17. The regulating member of one of the claims 1 to 16, wherein said position of equilibrium is a stable position of equilibrium in which the magnetic attraction between the fixed magnets and the mobile magnets is minimal.
18. The regulating member of one of the claims 1 to 17, having the same number of mobile magnets (30) as fixed magnets (40).
19. The regulating member of one of the claims 1 to 18, wherein, at the position of equilibrium:

    each fixed magnet (40) is arranged for exerting a magnetic field of equal intensity on two mobile magnets (30),

    and each mobile magnet (30) is arranged for exerting a magnetic field of equal intensity on two fixed magnets (40).
20. The regulating member of one of the claims 1 to 19, wherein said mobile magnet or magnets (30) are fixed relative to said balance (3).
21. The regulating member of claim 20, wherein said balance (30) is symmetrical relative to said rotation axle (300).
22. The regulating member of one of the claims 20 or 21, wherein said mobile magnets (30) are placed in symmetric fashion around said rotation axle (300).
23. The regulating member of one of the claims 1 to 22, having mechanical and/or magnetic stops to limit the amplitude of possible rotations of said balance (3).
24. The regulating member of one of the claims 1 to 23, wherein said balance is constituted by a mobile permanent magnet (30).
25. The regulating member of one of the claims 1 to 24, wherein said at least one mobile permanent magnet (30) is linked to the pallets (20) that thus also constitute the balance.
26. The regulating member of one of the claims 1 to 25, wherein said at least one mobile permanent magnet (30) is mounted in the plane of the balance and wherein said at least one fixed permanent magnet (40) is mounted in a plane parallel to said balance.
27. The regulating member of claim 26, wherein said at least one fixed permanent magnet and said at least one mobile permanent magnet are each constituted by a disc having sectors of alternating polarities.
28. The regulating member of one of the claims 1 to 27, having means for compensating the variation of magnetic field linked to the temperature.
29. The regulating member of one of the claims 1 to 28, wherein said driving element (2) is constituted by a mechanical escapement, for example a Swiss pallets escapement.
30. The regulating member of one of the claims 1 to 29, wherein said escapement is a magnetic escapement.
31. The regulating member of one of the claims 1 to 30, said balance (30) being held by at least one magnetic bearing (410, 420).
32. The regulating member of one of the claims 1 to 31, the position of said at least one magnet (30, 40, 47) being adjustable for regulating the frequency of the oscillations of said balance (3).
33. The regulating member of one of the claims 1 to 32, at least one said magnet (30) acting on an electronic system (44, 45, 46) to correct or determine the frequency of oscillation of said balance (3).
34. The regulating member of claim 33, said electronic system having at least one Hall sensor or a magnetoresistive sensor (44) subjected to the action of the magnetic field of one of the magnets to generate a measuring signal depending on the oscillations of said balance.
35. The regulating member of one of the claims 33 or 34, said electronic system having at least one coil (45) subjected to the action of the magnetic field of one of the mobile magnets (30) to generate a signal depending on the oscillations of said balance (3).
36. The regulating member of one of the claims 33 to 35, having at least one electronic circuit powered by the electro-motor force generated by the displacement of one of said magnets in the proximity of a coil.
37. The regulating member of one of the claims 1 to 36, having at least one bridge made of a non-magnetic material.
38. The regulating member of one of the claims 1 to 37, having a magnetic screen (41, 42) in order to protect external elements from the magnetic field generated by said permanent magnets.
39. The regulating member of one of the claims 1 to 38, wherein the displacements of said balance (30) are constrained by a guiding surface (43).
40. The regulating member of one of the claims 1 to 39, arranged in a way that the return force of said balance (30) varies linearly with the angular position (d) of the balance (3).
41. The regulating member of one of the claims 1 to 40, wherein said balance moves along a circular trajectory,
    the volume of the fixed and/or mobile magnets and/or their magnetization varying in continuous manner along said trajectory.
42. The regulating member of claim 41, wherein said balance (3) oscillates around a position of equilibrium along a circular trajectory,
    the magnetic interaction between said fixed permanent magnets and said mobile permanent magnets increases when the balance moves away from said position of equilibrium along said trajectory, so as to achieve an increasing return force.
43. The regulating member of one of the claims 1 to 42, wherein at least one of said fixed and/or mobile permanent magnets (30, 40) is magnetized in non-homogenous manner.
44. The regulating member of one of the claims 1 to 43, wherein said balance is constituted of several oscillating elements connected by a cinematic chain and oscillating with variable frequencies.
45. Mechanical movement for wristwatch having a regulating member according to one of the claims 1 to 44.
46. Movement according to claim 45, wherein the cinematic chain between said regulating member and the display elements has at least one belt of non-magnetic material.
47. Movement according to one of the claims 45 to 46, wherein at least one portion of said balance (3) is visible from outside the movement.

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