CH703274A2 - High frequency inertia adjusted balance wheel for balance wheel-hairspring of high frequency oscillator of watch, has counterweight whose part is made of material that is more dense than material forming felloe - Google Patents

Abstract

The wheel (1) has an inertial counterweight (7) fixed in a housing (8) of a continuous or discontinuous peripheral felloe. The counterweight has two parts (10, 11) that are adjustable in translation with respect to one another in a plane parallel to a balance plane (4). One of the parts is immovable in translation with respect to the felloe. Each part is made of material that is more dense than material forming the felloe. The felloe is formed as a single piece with a junction surface (6) i.e. disk, and a hub (2) using silicon, micro-machining material or quartz or using LIGA method.

Description

Description

The invention relates to a balance for a timepiece, with inertia adjustment to adjust its oscillation frequency, comprising a hub arranged to cooperate with a balance shaft perpendicular to a balance plane, and a peripheral serge continuous or discontinuous, connected to said hub by at least one junction surface, said balance further comprising at least one flyweight, said at least one flyweight being attached to said serge in a housing that comprises the periphery of said serge for its reception .

The invention also comprises a sprung balance incorporating such a balance.

The invention also relates to a timepiece incorporating such a sprung balance or such a balance.

The invention relates to the field of regulating organs for timepieces, and particularly the balance or balance-spiral.

The accuracy of the gauges depends on the quality of their regulating organ, and obtaining very high oscillation frequencies, for example 10 Hz, to be compared to the usual frequencies of 2.5 to 4 Hz, can not be used. obtained only with the design of suitable regulating members, in particular with regard to the pendulum.

Indeed, the energy to be provided, in the form of elastic torque of the spiral, for the maintenance of the oscillation is proportional to the product, on the one hand the inertia of the balance about its pivot axis, by the square of the frequency on the other hand. Thus, for example, at equal energy, the passage of a frequency from 4 Hz to 10 Hz results in about the division by 6 of the inertia. For a frequency of 4 Hz, a pendulum inertia of 12 mg.cm2 is considered as good, such a rocker classically having a diameter of 9 to 10 mm. Thus, a balance for use at 10 Hz must have a low value inertia, especially less than 2 mg.cm <2>.

A rocker for use at 10 Hz must still, for optimal operation, be of minimum mass, especially less than 30 mg, so as to reduce friction in the bearings, so as to avoid disturbances of isochronism in the different positions of use.

While being of low mass and inertia, the balance of a high frequency oscillator must still allow adjustment of unbalance and a perfect balance, static and dynamic, and its construction must allow adjustment operations. or / and adjustment. It is therefore not possible to use conventional technologies, or even solutions of lightened pendulums such as spokes with spoke serge as described by the patent FR 1 275 357 in the name of Straumann, or by the patent FR 1 301 938 in the name of LIP. Indeed, their mass, even reduced, prohibits to obtain as low inertia as desired. Similarly, a titanium pendulum according to patent EP 1 562 087 in the name of MONTRES BREGUET SA, designed with a serge and titanium arms and reduced sections, remains of mass and inertia which are greater than that. which is desired for optimal operation.

It is also sought a quality factor of the order of 500, so significantly higher than those of traditional oscillators where it is close to 220 to 280 for good quality watches. Such a quality factor can only be obtained by the combination of a silicon balance spring and a balance fulfilling the above conditions. Obtaining a high quality factor, combined with adjustment and adjustment possibilities, must, again, allow the elimination of the raquetterie.

Naturally, the mass of the assembly being limited, the number of components as small as possible is to be preferred.

The inventive step was to create the conditions of a balance structure, including the hub, the serge, and the connections between these two components as light as possible, away from the hub of the masses of density if possible greater than that of this structure.

For this purpose the invention relates to a balance for a timepiece, with inertia adjustment to adjust its oscillation frequency, comprising a hub arranged to cooperate with a balance shaft perpendicular to a balance plane, and a continuous or discontinuous peripheral serge, connected to said hub by at least one junction surface, said balance comprising at least one flyweight, said at least one flyweight being attached to said serge in a housing which comprises the periphery of said serge for its reception, characterized in that:

- Said at least one flyweight comprises profile guiding means complementary to complementary guide means that includes said housing;

each said at least one flyweight comprises at least two parts adjustable in translation relative to one another in a plane parallel to said plane of said balance, and one of said parts is immobile in translation relative to said serge,

each of said portions of said at least one feeder is made of a material which is denser than a first material constituting said serge.

According to a characteristic of the invention, said at least one flyweight comprises a first portion comprising said guide means, and a second portion constituted by a regulating screw, of which a thread, or respectively a tapping, cooperates with a tapping, respectively threading, that includes said first portion, and said threading, or respectively said tapping, does not cooperate with said serge nor with said junction surface.

According to another characteristic of the invention, said serge is made integrally with said junction surface and said hub in a micro-machinable material or in silicon or in liga or quartz.

According to another characteristic of the invention, each of said parts of said at least one feeder is made of a material, which is a heavy metal or beryllium bronze or gold or platinum or tantalum or molybdenum, or one of their alloys.

The invention also comprises a sprung balance incorporating at least one such rocker.

The invention also relates to a timepiece incorporating at least one such sprung balance or at least one such balance.

The preferred use of silicon provides a very light and very rigid balance structure, which can be dimpled in the junction zone between the hub and the serge. The transfer to the periphery of flyweights equipped with screws is favorable to obtaining a properly sized inertia despite the very low total mass of the balance. The adjustment and balancing functions are ensured and facilitated. The choice of a particular pair of materials, namely CuBe for a first feeder portion said stud inserted in a housing of the serge, and gold alloy for the adjusting screw screwed into this stud ensures, despite the very small dimensioning of this screw, a tightening torque ensuring its maintenance, without risk of breakage.

Such a balance is perfectly suitable for good operation at the frequency of 10 Hz, and even more so, since its dimensioning in diameter, in the following example of a preferred embodiment, is greater than or equal to the usual diameter d a pendulum. It is therefore possible to reduce its diameter, and thus further reduce its mass and inertia, for frequencies greater than 10 Hz.

Other advantages of the invention will appear on reading the description which follows, with reference to the appended figures in which:

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- fig. 14 represents, schematically and in perspective, a first variant of a balance according to the invention; represents, in a similar way to FIG. 1, a second variant of the invention shows schematically and in perspective a detail of FIG. 2 highlighting a weight of inertia; represents, in a similar way to FIG. 1, a third variant of the invention represents, in a similar way to FIG. 3, a detail of FIG. 4; represents, schematically and in front view, the second variant object of FIG. 2; represents, schematically, a section along the plane AA of FIG. 6; represents, schematically, a section along the plane BB of FIG. 6; represents, schematically and in front view, the third variant object of FIG. 4; represents, schematically, a section along the plane AA of FIG. 9; represents, schematically, a section along the plane BB of FIG. 9; represents, schematically and in section in a median plane, a detail of a particular embodiment of the invention; represents, in a similar way to FIG. 12, a detail of another particular embodiment of the invention; represents, schematically, partially and in front view, a detail of a rocker according to the invention comprising a junction area perforated between the hub and the serge.

The invention relates to the field of regulating organs for timepieces, and particularly the balance or balance-spiral.

The invention is particularly directed to the production of rockers for high oscillation frequencies, 10 Hz or more.

Three non-limiting embodiments are shown in the figures.

The invention relates to a pendulum 1 for a timepiece, with inertia adjustment to adjust its oscillation frequency, comprising a hub 2 arranged to cooperate with a balance shaft 3 perpendicular to a plane of equilibrium.

3 lance 4, and a peripheral serge 5 continuous or discontinuous. This serge 5 can indeed be discontinuous in the context of a search for relief. The exemplary embodiments of the figures show a continuous serge, which offers the advantage of good rigidity and good aerodynamics, and which limits the localized flexions by preventing any warping of the balance.

This serge 5 is connected to the hub 2 by at least one junction surface 6, which may be constituted by a continuous surface such as a perforated disc or not, or by one or more arms 22. The making of a surface of junction 6 openwork, including cuts, through or not, between longitudinal members ensuring good triangulation, further reduces the weight of the balance.

Fig. 3 14 shows an exemplary embodiment with an arm 22 comprising such a perforated structure, in a mixed manner, with, separated by ribs 30, pockets 29 passing through the entire thickness of the joining surface 6, in particular of the arm 22, or and blind pockets 31, not through, on only part of the thickness of the junction surface 6, in particular the arm 22, for example a third, each separated from another similar blind pocket on the other side arm 22 by a canvas of comparable thickness. The good triangulation carried out allows a sensible economy of mass, a conventional finite element calculation makes it possible to determine the longitudinal members 30 which are essential for the mechanical strength and the resistance to twisting. Of course, the annular portion of the serge 5 can also be perforated similarly. It is the same if it is preferred a continuous junction surface 6 such as a disk or the like.

This balance 1 also comprises at least one flyweight 7. Such a flyweight 7 is reported on or in the serge 5 in a housing 8 that includes the periphery of the serge 5 for its receipt.

According to the invention:

this weight 7 comprises guiding means 9 of complementary profile to complementary guiding means 9A that includes the housing 8 with which this weight 7 cooperates;

each such weight 7 comprises at least two parts 10, 1 1, which are adjustable in translation relative to each other in a plane parallel to the plane 4 of said beam 1, and one of which parts 10; 1 1, is immobile in translation relative to the serge 5;

each of these parts 10, 1 1 of such a weight 7 is made of a material which is denser than a first constituent material of the serge 5.

Such a weight 7 and comprises a first portion 10 comprising the guide means 9 and said pad, and a second portion 1 1 preferably constituted by a set screw 12, a thread, or respectively a tapping, cooperates with a tapping, respectively a thread, that includes the first portion 10, and whose thread, or respectively the thread, is at a distance from the serge 5 or the junction surface 6.

In a first embodiment, as visible in particular on the first variant of FIG. 1 and on the second variant of FIG. 2, the guide means 9 and the complementary guide means 9A are linear.

In a second embodiment, as visible in particular on the third variant of FIG. 4, the guide means 9 and the complementary guide means 9A are circular.

Preferably, this flyweight 7 is held in its housing 8 by holding means 13. The latter can be of different natures, including:

- Geometric holding means arranged to prohibit the extraction of this feeder 7 from its housing 8, as visible in the second embodiment of FIG. 2;

- permanent holding means made by driving or gluing or brazing or welding; in the case of bonding a set of about 10 microns is to be provided to adjust the amount of glue and allow a correct grip;

- Elastic holding means arranged to allow the introduction of this feeder 7 in its housing 8 and to prohibit its extraction, as shown in Figs. 12 or 13.

Preferably, when the holding means 13 are constituted by resilient holding means, these are constituted by clipping means 14 that comprises the flyweight 7, and which are arranged to cooperate elastically with means complementary clipping 14A that includes the serge 5.

Preferably, the assembly by clipping is irreversible.

In the embodiments shown in FIGS. 12 and 13, the elastic holding means are constituted by at least one elastic lip 15 that comprises the flyweight 7 or the housing 8. This elastic lip 15 is arranged to flex in a compression position during a first insertion stroke of the weight 7 in the housing 8 and allow this introduction, and to relax in a position of relaxation in a recess 16 that respectively comprises the housing 8 or the weight 7, in a service position or in a second race of this regulator 7, this second regulating race following the first introductory race. This elastic lip 15 has a stop surface 17 arranged to abut, when the lip 15 is in this detent position, with a complementary stop surface 17A arranged in return that comprises the housing 8 or the weight 7.

In some embodiments, as the first variant of FIG. 1, or the third variant of FIG. 4, the screwing or unscrewing of the adjusting screw 12 brings closer or moves away, or conversely, one end of this adjusting screw 12 of the serge 5, the first part 10 or pad of the feeder 7 being motionless in translation. In this version, the stud has the main function of the support of the adjusting screw 12, and can therefore be reduced to its simplest expression screw insert.

In other embodiments, like the second variant of FIG. 2, the screwing or unscrewing of the adjusting screw 12 brings closer or moves away, or conversely, one end of this feeder 7 carrying this screw 12, in particular the stud 10 carrying the screw 12, of the serge 5, this adjusting screw 12 being motionless in translation. In this embodiment, as shown in FIGS. 3, 7 and 8, the adjusting screw 12 has a shoulder 18, respectively a groove, arranged to cooperate in a complementary manner with a groove 19, respectively a shoulder, that includes the serge 5.

Preferably, when the stud 10 is movable, as the second variant of FIG. 2, the rocker 1 comprises blind clearance means 20 on the hub side 2. These release means 20 are arranged to allow the insertion of the flyweight 7 to the hub 2, then the setting in position. the adjusting screw 12, or adjusting screws 12 if there are several, by cooperation between the shoulder 18 and the groove 19. This adjusting screw 12 is then further away from the hub 2 than the weight 7 with which it constitutes a captive assembly when they are connected by a thread, respectively tapping one, cooperating with a thread, respectively a thread of the other.

In this same second variant of FIG. 2, the stud 10 has an H-shaped profile arranged to cooperate with a straight notch 21 that includes the serge 5.

In a particular version of the invention, as shown in FIGS. 2 and 6, and in no way limiting, this notch 21 is radial with respect to the hub 2.

In the second embodiment, as visible in particular on the third variant of FIG. 4, the stud 10 has a cylindrical profile arranged to cooperate with a cylindrical bore of the housing 8 of said serge 5. In a variant not shown in the figures, the stud 10 has a profile with a right outer toothing, which is arranged to cooperate with a right internal toothing that includes the housing 8 of the serge 5.

Preferably, as shown in the figures, the adjusting screw 12 is radial with respect to the hub 2.

In a variant not shown in the figures, the weight 7 comprises at least two adjusting screws of inertia 12

Preferably, and as illustrated by the figures, the balance 1 comprises at least two weights 7A, 7B, each attached to the serge 5 in a housing 8A, 8B, which comprises the periphery of the serge 5 for its reception. These weights 7A, 7B each comprise guide means complementary to complementary guiding means that includes the housing 8A, 8B, and each comprise at least two parts 10, 1 1 adjustable in translation with respect to the another in a plane parallel to the plane 4 of the balance 1, and each of these parts 10, 1 1 of each of these weights 7A, 7B is made of a material which is denser than a first constituent material of the serge 5.

Preferably these weights 7A, 7B are symmetrical in pairs relative to a plane passing through the hub 2 and the balance shaft 3.

Preferably these weights 7A, 7B are symmetrical two by two with respect to said hub 2.

In a preferred embodiment, as shown in the figures, the flyweights 7 are four in number, arranged along two perpendicular axes passing through the hub 2 and in the plane 4 of the balance. The 4 associated adjusting screws 12 allow all the angular possibilities of unbalance creation. The case where several adjusting screws are embedded on the same pad gives even more adjustment latitude.

In a particular embodiment, corresponding in particular but not limited to the second variant of FIG. 2, the first part of said feeder 10 pad is dimensionally stable.

In order to limit the aerodynamic drag, each flyweight 7, and in particular each moving part 1 1 feeder or adjusting screw 12, is set back from a circle circumscribed to the serge 5, in any relative position of the parts which constitute this weight.

For additional lightening purposes, the serge 5 may include one or more cutouts 23, peripheral as in FIG. 4, or on the inner part of the serge 5 in another embodiment not shown in the figures.

In a preferred embodiment, as shown in the figures, the junction surface consists of at least one arm 22. Thanks to the use of a silicon technology, such an arm can adopt any profile, including a curve , Or other. It may also include lightening, through or not, for example in the form of triangular pockets, which provide rigidity while allowing a significant weight loss. The figures represent even-numbered versions of arms diametrically opposed two by two.

In the first variant of FIG. 1, these arms 22 are alternated with the weights 7, the periphery of the serge 5 comprises an alternation of surfaces which are all rigid: T-shaped joining surfaces 24 between the arms 22 and serge 5 on the one hand, and the surfaces reinforced support 25 comprising the housings 8 to receive the weights 7 on the other hand.

In another type of embodiment, a counterweight 7 is located in the alignment of some arms 22, or even in alignment with each arm 22, as in the second variant of FIG. 2, or the third variant of FIG. 4, and the reinforced junction zone of the arms 22 to the serge 5 may comprise a notch 21, which is functional or which is a relief.

It is necessary to be able to conveniently adjust the unbalance on the one hand, and correct the inertia on the other hand, and especially adjust very precisely the frequency of the oscillator.

Balancing a balance is an important operation, for which we seek a high balancing accuracy, of the order of microgram x cm.

Advantageously, each weight 7 is profiled in a particular way, so as to allow, separately or at the same time:

a balancing facilitated by the existence of at least one plane surface, which is constituted either by a so-called parallel flat surface 26 which is parallel to the balance plane 4, or by a flat end surface 27 which is perpendicular to 4 and a radial plane coming from the balance shaft 3. A same flyweight 7 may comprise both one or more parallel surfaces 26, and one or more end surfaces 27, in particular, as visible in FIGS. , an end surface on the first part 10 or the pad, and an end surface 27 on the second part 1 1 or the adjusting screw 12. It is then easy to perform balancing by milling or etching or other on the one of these surfaces 26 and / or 27, or by addition of material, in particular by brazing, welding or plasma if the pad 10 and / or the adjusting screw 12 is metallic;

a reduced aerodynamic drag, the flyweight 7 then comprising, in any section perpendicular to the balance plane 4 and to a plane passing through the balance shaft 3, an aerodynamic profile 28 radiated and / or sloping to reduce its friction in the air.

Preferably, all weights that includes the balance 1 are weights 7 in two parts 10 and 1 1 as described above.

Preferably and specific to the invention, the serge 5 is made integrally with the junction surface 6 and the hub 2 in silicon preferably, or a micro-machinable material, or quartz, or according to the LIGA process.

The use of silicon allows dimensioning in diameter substantially greater than one would, at similar inertia, with a balance of traditional invoice. Here, the rockers of the three variants presented have a diameter of about 7 mm.

The choice of silicon, in particular, allows the realization, in the serge, elastic holding means of the weights 7, in particular in the form of elastic lip 15. In the same way, stop means in the form of ratchets can be combined with such blades or springs made in the silicon serge.

This choice of silicon or liga allows, by the excellent resolution during shaping, to ensure a very precise geometry of the serge 5, and thus avoid all games generating vibrations and detrimental to the proper functioning of the oscillator.

The choice of silicon allows moreover to insert the pendulum engravings, decorations, and perform a surface patterning.

Preferably, each of the parts 10, 1, 1 of each counterweight 7 is made of a material, which is a heavy metal, or beryllium bronze, or gold or platinum or tantalum or aluminum. molybdenum, or one of their oxides or their nitrides, or one of their alloys, or one of the complexes developed on their bases.

Preferably, when the second part 1 1 is a control screw 12, it is necessary to reconcile the very small diameter of the threaded portion, typically between 0.20 and 0.30 mm, with a torque of screwing / unscrewing which ensures its good retention in the stud 10, this pair being chosen in particular between 0.3 and 1, 8 N. mm. It is then necessary to have a pair of materials for the stud 10 and the regulating screw 12, which ensures both the holding of the screw 12 without unscrewing, and which prevents its breaking at the maximum value of the torque. In a preferred embodiment, this pair of materials consists of beryllium bronze of CuBe type on the one hand, and a gold alloy, at least 14 karat, on the other hand. Preferably the stud 10 is beryllium bronze CuBe type and the adjusting screw 12 is made of gold alloy.

Finally, for optimal use, and to further increase the quality factor, it is necessary to reduce the friction at the pivot of the pendulum. Precisely, the mass and reduced inertia of the balance according to the invention allow the manufacture of a lower diameter of the pivot of 30 to 40% relative to the usual pivots, which has a very large influence on the level of friction. The three variants presented are conjugated to a pivot with a diameter of approximately 0.05 mm.

By way of example, for a rocker 1 with a diameter of about 7 mm and a serge thickness of about 0.20 mm, comprising a monobloc serge made of silicon, and 4 pads of CuBe or made of gold alloy and 4 regulating screws 12 in

6

Claims (10)

gold alloy, the masses and inertias with respect to the balance shaft 3, for the three embodiments shown in the figures are the following: Mass serge 6.8 to 1 1, 3 mg Inertia serge 0.41 to 0.92 mg.cm <2> Mass plots 3, 1 to 17.2 mg Inertia plots 0.24 to 1, 13 mg.cm <2 > Mass screw 2.4 to 6.2 mg Inertia screw 0.23 to 0.64 mg.cm <2> Mass together 20.6 to 26.9 mg Inertia together 1, 80 to 1, 81 mg.cm <2 > It will be noted, again, that, according to the invention, the unbalance of the weights 7 is decomposed between an unbalance portion which is fixed, and a part of the unbalance which is movable and serves as an adjustment. Thus, in the second variant of FIG. 2, the studs 10 constitute the regulating part of the unbalance, and the screws 12 are fixed in translation and constitute the fixed part of the unbalance. In the third variant of FIG. 4, it is the opposite: the studs 10 constitute the fixed part of the unbalance, and the screws 12 constitute the regulating part. Preferably, for a given inertia, the regulating part is always of the same value. In the examples above, the inertia of the regulating part is close to 0.25 mg.cm <2>. The quality factor measured is close to 500 for the three variants. This quality factor is obtained by the combination of a silicon balance spring and a balance according to the invention. The combination between on the one hand this high quality factor, and on the other hand the adjustment and adjustment possibilities offered by the studs 10 and the adjusting screws 12, which, in addition to their own adjustment functions, fill a new function, which is to serve as a machining platform for adding or removing material in the balancing and frequency adjustment adjustment operations, allows the elimination of the racking. The goals that proposed to achieve the invention are fully achieved with such values. In particular, such a balance with an inertia less than 2 mg.cm <2>, here from 1.80 to 1.81 mg.cm <2>, is entirely suitable for use at 10 Hz or more. The adjustment and balancing possibilities are also excellent. The adjustment and adjustment of the balance are very accurate, and allow the pendulum to be used in a high frequency oscillator, 10 Hz or more. The design of the balance allows a very precise adjustment of the oscillation frequency of the sprung balance in which it is integrated. The invention also comprises a spiral balance incorporating at least one such rocker 1 according to the invention. The invention also relates to a timepiece incorporating at least one such sprung balance or at least one such rocker 1. claims 1. Pendulum (1) for a timepiece, with inertia adjustment for adjusting its oscillation frequency, comprising a hub (2) arranged to cooperate with a balance shaft (3) perpendicular to a balance plane (4), and a continuous or discontinuous peripheral serge (5) connected to said hub (2) by at least one junction surface (6), said rocker (1) also comprising at least one flyweight (7), said at least one weight (7) being attached to said serge (5) in a housing (8) that comprises the periphery of said serge (5) for its reception, characterized in that: - Said at least one feeder (7) comprises guiding means (9) of complementary profile to complementary guiding means (9A) that comprises said housing (8); each said at least one feeder (7) comprises at least two parts (10, 1 1), adjustable in translation relative to one another in a plane parallel to said plane (4) of said balance (1), and one of said parts (10; 1 1) is immobile in translation relative to said serge (5); each of said portions (10, 1 1) of said at least one feeder (7) is made of a material which is denser than a first material constituting said serge (5). 2. Pendulum (1) according to claim 1, characterized in that said at least one flyweight (7) comprises a first portion (10) comprising said guide means (9), and a second portion (1 1) constituted by a adjusting screw (12), a thread, or respectively a tapping, cooperates with a thread, respectively a thread, that includes said first portion (10), and said threading, or said tapping, is at a distance from said serge ( 5) or said joining surface (6). 7 3. Pendulum (1) according to claim 2, characterized in that the screwing or unscrewing of said adjusting screw (12) moves or removes, or conversely, an end of said screw (12) of said serge (5), said first part (10) being immobile in translation. 4. Pendulum (1) according to claim 2, characterized in that the screwing or unscrewing of said adjusting screw (12) moves or moves away, or conversely, an end of said at least one feeder (7) carrying said at least one a screw (12) of said serge (5), said at least one screw (12) being immobile in translation. 5. Pendulum (1) according to the preceding claim, characterized in that said adjusting screw (12) comprises a shoulder (18), respectively a groove, arranged to cooperate in a complementary manner with a groove (19), respectively a shoulder, that includes said serge (5). 6. Pendulum (1) according to the preceding claim, characterized in that it comprises blind release means (20) on the side of said hub (2) and arranged to allow the insertion of said at least one feeder (7) to said hub (2), then placing said at least one adjusting screw (12) in position by cooperation between said shoulder (18) and said groove (19), said at least one adjusting screw (12) then being further away from said hub (2) that said flyweight (7) with which it constitutes a captive assembly when they are connected by a thread, respectively tapping of one, cooperating with a thread, respectively a thread of the other. 7. Pendulum (1) according to claim 2, characterized in that said at least one feeder (7) comprises at least two adjusting screws of inertia (12). 8. Pendulum (1) according to one of the preceding claims, characterized in that said at least one flyweight (7) is held in said housing (8) by holding means (13) which are resilient holding means arranged to allow the introduction of said at least one feeder (7) into said housing (8) and to prohibit its extraction. 9. Pendulum (1) according to the preceding claim, characterized in that said elastic holding means are constituted by clipping means (14) that comprises said at least one feeder (7), and which are arranged to cooperate elastically with complementary clipping means (14A) that comprises said serge (5), said clipping means (14) being constituted by at least one elastic lip (15) that comprises said at least one flyweight (7) or said housing (8). ), said at least one elastic lip (15) being arranged to flex in a compression position during a first insertion stroke of said at least one feeder (7) into said housing (8) and to allow said insertion, and to to relax in a detent position in a recess (16) which respectively comprises said housing (8) or said at least one feeder (7) and constituting said complementary clipping means (14A), in a posit service ion or in a second regulating stroke of said at least one flyweight (7), said second regulating stroke following said first insertion stroke, said at least one elastic lip (15) having a stop surface ( 17) in said detent position arranged to abut with a complementary stop surface (17A) arranged in return that includes said housing (8) or said at least one feeder (7). 10. Pendulum (1) according to one of the preceding claims, characterized in that it comprises at least two weights (7A, 7B), each attached to said serge (5) in a housing (8A, 8B), that includes the periphery of said serge (5) for its reception, each comprising means for guiding profile complementary to complementary guiding means that includes said housing (8A, 8B), each comprising at least two parts (10, 1 1) adjustable in translation with respect to one another in a plane parallel to said plane (4) of said beam (1) ,. and each of said portions (10, 1 1) of each of said weights (7A, 7B) being made of a material which is denser than a first material constituting said serge (5). 1 1. Balance (1) according to the preceding claim, characterized in that said flyweights (7A, 7B) are symmetrical in pairs relative to a plane passing through said hub (2) and said balance shaft (3), and / or are symmetrical two by two with respect to said hub (2). 12. Pendulum (1) according to one of the preceding claims, characterized in that each said flyweight (7) comprises at least one plane surface formed, or a parallel surface (26) parallel to said balance plane (4), or an end surface (27) perpendicular to said balance plane (4) and a radial end of said balance shaft (3), said planar surface being arranged able to serve as a machining platform to add or remove of matter in balancing and frequency adjusting operations, and said weight (7) comprises, in any section perpendicular to said balance plane (4) and to a plane passing through said balance shaft (3) , an aerodynamic profile (28) radiated or / and sloping to reduce its friction in the air. 13. Pendulum (1) according to one of the preceding claims, characterized in that said joining surface (6) is perforated, and comprises, separated by ribs (30), pockets (29) through the entire thickness said junction surface (6), and / or non-through-through blind pockets (31) over only a part of the thickness of said joining surface (6). 14. Pendulum (1) according to one of the preceding claims, characterized in that said serge (5) is made integrally with said junction surface (6) and said hub (2) made of silicon or in a micro-material. machinable or quartz or liga. 15. Pendulum (1) according to one of the preceding claims, characterized in that each of said parts of said at least one feeder (7) is made of a material, which is a heavy metal or beryllium bronze or gold or platinum or tantalum or molybdenum or one of their oxides or their nitrides, or one of their alloys, or one of the complexes developed on their bases. 16. Spiral balance incorporating at least one balance (1) according to one of the preceding claims. 17. Timepiece incorporating at least one sprung balance according to the preceding claim, or at least one balance (1) according to one of claims 1 to 15. 9