EP2980658B1 - Device for assembling and adjusting a hairspring - Google Patents

Description

Technical area

The present invention relates to a device for assembling and adjusting a hairspring intended to cooperate with a terminal turn of a hairspring whose inner end is integral with a balance shaft, the latter being pivoted in a bridge. balance.

• une base, destinée à être assemblée au pont de balancier avec une orientation angulaire ajustable et, comprenant une surface d'appui sensiblement cylindrique, de rayon sensiblement égal au rayon de la spire terminale, et une semelle d'appui adjacente à la surface d'appui, la surface d'appui et la semelle d'appui définissant une position de service de la spire terminale,
• un premier bras s'étendant à partir de la base et portant un organe de verrouillage de la spire terminale agencé pour maintenir cette dernière en appui contre la surface d'appui.

More specifically, the invention relates to such a device comprising

• a base, intended to be assembled to the balance bridge with an adjustable angular orientation and, comprising a substantially cylindrical bearing surface, of radius substantially equal to the radius of the end turn, and a bearing plate adjacent to the surface of support, the bearing surface and the support plate defining a service position of the terminal turn,
• a first arm extending from the base and carrying a locking member of the end turn arranged to maintain the latter bearing against the bearing surface.

State of the art

In the current assembly and adjustment mechanisms, the outer end of the hairspring is immobilized by a peg fixed to a peg holder secured to a cock. A racket movable in rotation relative to the bolt carrier is provided to adjust the active length of the hairspring. Generally, the racket can have two arms: a first bearing two pins between which the hairspring is free, a second, optional, serving as a lever to rotate the racket along the axis of the pendulum. When the racket pivots, the active length of the hairspring is reduced or increased.

Other types of assembling devices and spiral adjustment have been designed, especially for the purpose of simplifying the assembly of the spiral and the adjustment of its active length. The patent application WO 2006/102911 A1 presents an example. The device presented in this document comprises a single arm frictionally mounted on the balance bridge to allow adjustment of the marker. The arm is provided with a circular groove defining a service position of the end turn of the spiral at the bottom of which it is maintained in support by a rotary member striated on the portion of its periphery arranged in abutment against the hairspring. According to this document, the striated rotary member thus defines the active length of the hairspring, while two pins are carried by the other hand by the arm, on either side of the corrugated rotary member and close to the circular groove, for ensure guidance of the end turn.

A main disadvantage of this device comes from the structure of the cooperating bodies with the final turn of the spiral. Indeed, the latter is extremely fragile and delicate, and its chronometric properties degrade very quickly due to mechanical stresses it could suffer. In the case of this device of the prior art, the mechanical stress experienced by the hairspring, because of its interaction with the striated rotary member, has a significant risk of degradation of its qualities. In particular, the rotary member must necessarily apply some pressure on the hairspring to ensure its drive, which causes damage to the hairspring. In addition, it is likely that the hairspring may suffer further damage by its cooperation with the guide pins. Typically, this type of pin requires a manual recovery, after mounting on the arm, to precisely adjust the distance separating it from the bottom of the circular groove. Thus, it is common that the periphery of a pin is not exactly parallel to the spiral wafer, which may give rise to friction in operation, leading to a loss of accuracy time over time. Finally, mounting the hairspring on such a device already has a significant risk of deterioration because its handling is complex during this operation to put it in place.

Disclosure of the invention

An object of the invention is to overcome the drawbacks of assembly devices and adjustment of a spiral already known, by providing such a device for performing a simplified assembly and adjustment of the spiral, free of any mechanical stress that could cause damage to the hairspring.

• un second bras s'étendant à partir de la base et portant un sabot susceptible d'être agencé à une distance prédéfinie de la surface d'appui pour coopérer avec la spire terminale, et
• un organe de commande mobile entre des première et seconde configurations et agencé de telle manière qu'il est susceptible d'agir sur le second bras et le déformer de manière élastique pour déplacer le sabot en référence à la base, les première et seconde configurations de l'organe de commande étant associées, respectivement, à une première position du second bras, dans laquelle le sabot est situé à une distance de la surface d'appui égale à la distance prédéfinie, et à une seconde position du second bras, dans laquelle le sabot est situé à une distance de la surface d'appui supérieure à la distance prédéfinie.

For this purpose, the present invention relates to an assembly and adjustment device of the type mentioned above, further comprising

• a second arm extending from the base and carrying a shoe capable of being arranged at a predefined distance from the bearing surface to cooperate with the end turn, and
• a movable control member between first and second configurations and arranged such that it is capable of acting on the second arm and deforming it elastically to move the shoe with reference to the base, the first and second configurations of the control member being associated, respectively, with a first position of the second arm, wherein the shoe is located at a distance from the bearing surface equal to the predefined distance, and at a second position of the second arm, wherein the shoe is located at a distance from the support surface greater than the predefined distance.

According to a preferred embodiment, the first and second configurations of the control member are stable configurations.

Thanks to these characteristics, the shoe defining the active length of the hairspring can be removed from the base of the device, when the hairspring is put in place or when a watchmaker makes its adjustment, then resume precisely its service position.

Preferably, the control member comprises an eccentric arranged on the second arm so that it can be pivoted in response to an action of a user, to switch from one to the other of its configurations and exert pressure on the base, in the second configuration, such that the shoe is located at a distance from the support surface greater than the predefined distance.

Alternatively, the control member may comprise an eccentric arranged on the base such that it can be rotated in response to an action of a user, to switch from one to the other of its configurations and exert pressure on the second arm, in the second configuration, such that the shoe is located at a distance from the support surface greater than the predefined distance.

Furthermore, the second arm may advantageously comprise, from the base towards its free end, a first substantially radial portion and terminated by a bend ensuring the connection with a second substantially tangential portion, the first and second portions and the bend being arranged such that whereby the elastic deformation experienced by the second arm, in response to a change of configuration of the control member, occurs essentially at the level of the first portion.

Similarly, the first arm may advantageously comprise, from the base towards its free end, a first substantially radial portion and terminated by a bend ensuring the connection with a second substantially tangential portion, the first and second portions and the elbow being arranged such that the first arm is able to undergo an elastic deformation intervening essentially at the level of its first portion.

With such a construction, a locking member can be used which is not likely to cause damage to the hairspring. Indeed, the locking member being also carried by an elastic arm, the pressure it applies to the spiral can be adjusted finely and the integrity of the spiral is not compromised in case of shock.

According to a preferred embodiment, the locking member comprises a wheel arranged on the first arm so that it is pivotable in response to a suitable action of a user to drive the end turn in translation in one direction. or in the other depending on its direction of rotation.

The wheel may advantageously comprise a substantially cylindrical portion of synthetic material intended to be arranged in abutment against the end turn in its service position.

In general, it is advantageous to provide that the shoe is arranged in abutment against the base of the device in the first position of the second arm which carries it, so that it can be positioned at the predetermined distance from the bearing surface. with great precision.

The present invention also relates to a watch movement provided with a device for assembling and adjusting a spiral according to the characteristics that have just been stated, as well as a timepiece including such a watch movement.

Brief description of the drawings

• les figures 1 et 2 représentent des vues de face simplifiées, suivant des premier et second côtés respectifs, d'un balancier-spiral muni d'un dispositif d'assemblage et de réglage du spiral selon un mode de réalisation préféré de l'invention;
• la figure 3 représente une vue en perspective éclatée de détails de construction du dispositif selon le mode de réalisation préféré des figures 1 et 2;
• la figure 4 représente une vue en coupe transversale simplifiée du dispositif selon le mode de réalisation préféré des figures 1 et 2, la coupe étant réalisée suivant la ligne IV-IV de la figure 1, et
• les figures 5 et 6 représentent des vues de face simplifiées similaires à la vue de la figure 1, dans des première et seconde configurations respectives du dispositif selon le mode de réalisation préféré des figures 1 et 2.

Other characteristics and advantages of the invention will appear more clearly in the following detailed description, with reference to the accompanying drawings given by way of non-limiting examples and in which:

• the Figures 1 and 2 are simplified front views, along first and second respective sides, of a sprung balance provided with a device for assembling and adjusting the hairspring according to a preferred embodiment of the invention;
• the figure 3 represents an exploded perspective view of construction details of the device according to the preferred embodiment of the Figures 1 and 2 ;
• the figure 4 represents a simplified cross-sectional view of the device according to the preferred embodiment of the Figures 1 and 2 , the section being taken along line IV-IV of the figure 1 , and
• the Figures 5 and 6 represent simplified front views similar to the view of the figure 1 in respective first and second configurations of the device according to the preferred embodiment of the Figures 1 and 2 .

Mode (s) of realization of the invention

The Figures 1 and 2 represent general views from the front of a sprung balance equipped with a device for assembling and adjusting the hairspring according to a preferred embodiment of the invention, along first and second respective sides. Typically, the view of the figure 1 corresponds to a watch movement face that would be directly accessible, for example its bridges side, while the view of the figure 2 would be a view of the balance-spiral platinum side.

Conventionally, a hairspring 1 is fixed to a balance shaft 2 by its internal end (not visible). The balance shaft 2 has one end pivotally mounted in a balance bridge 6 in a conventional manner.

The hairspring 1 has a terminal turn 8 leading to its outer end 10.

The end turn 8 cooperates with a device for assembling and adjusting the spiral 12.

The device 12 comprises a base 14 mounted on the balance bridge 6 with an adjustable angular orientation. For this purpose, two screws 16 screwed into the balance bridge 6 and each of which passes through an oblong opening 18 formed in the base 14 are shown in an illustrative and nonlimiting manner. Thus, the screws 16 may be slightly loosened to allow an angular adjustment of the orientation of the device 12 with reference to the balance bridge 6. Once the screws 16 tightened, the angular orientation of the device 12 is fixed. As will emerge from the explanations that follow, such an adjustment makes it possible to adjust the reference of the sprung balance, in known manner.

The device 12 further comprises first and second arms 20 and 22, each of which carries a member respectively for locking and guiding the end turn 8, as will be apparent from the detailed description of the following figures.

Each arm 20 or 22 has a first portion 24 or 26, extending in a substantially radial direction from the base 14 and ending in a bend 28 or 30 providing the connection with a second portion 32 or 34 substantially tangential. It can be seen from the figures that, for each of the arms 20, 22, the first and second portions and the elbow are arranged in such a way that the arm is able to undergo an elastic deformation intervening essentially at the level of its first portion 24, 26.

The Figures 3 and 4 illustrate constructional details of the device 12 according to a preferred embodiment of the invention, as shown in FIGS. Figures 1 and 2 .

More specifically, the figure 3 represents an exploded perspective view partially illustrating the assembly and adjustment device 12 according to the preferred embodiment of the Figures 1 and 2 . The first and second arms 20, 22 have been cut on the view of the figure 3 , to clarify more.

It appears from figure 3 that the base 14 has a bearing surface 40, substantially cylindrical and of radius substantially equal to the radius of the end turn 8, and a bearing plate 42, adjacent to the bearing surface 40. In addition, a flange 44 is partially formed on the base 14 opposite the support plate 42, preferably but optional. The bearing surface 40 and the bearing plate 42 define a service position of the end turn 8, the axial retention of the end turn 8 in its operating position being improved by the rim 44.

Note that the support plate 42 and the flange 44 have notches 46 and 48 arranged opposite one another and whose function will be explained later.

Furthermore, the base 14 also has a recess 50 substantially in the form of a cylinder portion and whose function will also be explained below.

As mentioned above, the first arm 20 carries a locking member 52, shown in exploded view on the figure 3 . In particular, the locking member 52 has here, by way of nonlimiting illustration, a generally cylindrical shape and comprises a first portion 54, composed essentially of a synthetic material, preferably an elastomer, then a second portion 56 serving as a support at the first portion 54 and of substantially the same diameter as the latter. The second portion 56 ends on a third portion 58, substantially disc-shaped here, itself surmounted by a fourth portion 60 in the form of a screw head.

Advantageously, provision can be made for the second, third and fourth portions to be made in one piece, made of conventional metal or metal alloy, whereas the first portion 54 may be obtained for example by overmolding an elastomer on the other portions. . In particular, jolting of the junctions between the first and second portions may be provided to improve their mutual resistance when the locking member pivots, as will be explained below.

A mounting plate 62 is provided for assembling the locking member 52 to the first arm 20, at its second portion 32.

The method of assembling the locking member 52 on the first arm 20 is more particularly visible on the figure 3 as well as on the cross-sectional view of the figure 4 , according to the section line IV-IV of the figure 1 . The first and second arms 20, 22 are only partially illustrated in these figures for clarity.

The mounting plate 62 comprises a central hole 64 in which is arranged the second portion 56 of the locking member 52, so that the fourth portion 60 is housed in a hole 66 adapted to the first arm 20 to be accessible, such as that this appears in particular from the figure 1 . The third portion 58 of the locking member 52 is, in turn, housed in a recess 68 adapted to the first arm 20 to lock the locking member 52 between the first arm 20 and the mounting plate 62. Once assembled, the first portion 54 is arranged in abutment against the end turn 8 of the hairspring 1, at the notches 46, 48, to ensure its retention in its service position.

It is also apparent from figure 3 that the mounting plate 62 also comprises two pillars 70, arranged on either side of the central hole 64 and each having a curved face to provide a rotational guiding function of the locking member 52.

Regarding the second arm 22, it carries a guide member 72 of the end turn 8, as it appears from the figure 3 .

The guide member 72 has a wafer shape with two holes 74 intended to cooperate with two screws (numerical reference 76 on the figure 2 ) to ensure its assembly to the second portion 34 of the second arm 22.

Moreover, the guiding member 72 has a shoe 78 intended to cooperate with the end turn 8 of the hairspring 1 to guide them in its service position, or even to define the active length of the hairspring 1, as a function of the distance provided between the shoe 78 and the bearing surface 40 in the service configuration.

Finally, the guide member 72 has a hole 80 for accommodating the foot 82 of an eccentric 84. The eccentric 84 comprises a board 86 substantially disc-shaped, of which two opposite portions are truncated, surmounted by a screw head 88. Once the assemblies of the eccentric 82 on the guide member 72 and the latter on the second arm 22 made, the board 86 is arranged next to the recess 50 of the base 14.

The impact of the rotation of the eccentric 82 on the operation of the device 12 will now be exposed in relation to the Figures 5 and 6 which are simplified views similar to the view of the figure 1 .

The figure 5 represents the device 12 in a first configuration corresponding to the current operation of the balance-spring, while the figure 6 represents it in a second configuration, assembly or adjustment.

It appears that the eccentric 82 can pivot between two functional positions: a first in which it is not located in contact with the base 14 ( figure 5 ) and a second in which its plate 86 bears against the bottom of the recess 50 to spread its foot 82, and thus the second portion 34 of the second arm 22, from the base 14 ( figure 6 ).

It emerges from the foregoing explanations that the eccentric 84 acts as a control member, movable to alternatively take first and second configurations and arranged in such a way that it is capable of acting on the second arm 22, through its foot 82, to deform elastically when it passes from its first configuration, illustrated on the figure 5 , in its second configuration, illustrated on the figure 6 . Indeed, the action of the plate 86 on the base 14 of the device, passing from a truncated portion of small radius to a full portion of greater radius, causes a distance of the eccentric 84 with reference to the base 14 by deformation of the second arm 22.

Thus, the first and second configurations of the eccentric 84 are associated, respectively, with a first position of the second arm 22, in which the shoe 78 is located at a distance from the bearing surface 40 equal to a predefined distance by construction to cooperate with the end turn 8, and at a second position of the second arm 22, wherein the shoe 78 is located at a distance from the support surface 40 greater than the predefined distance and no longer cooperates with the end turn 8.

The predefined distance can be obtained by construction by conforming and dimensioning the second arm 22 so that the shoe 78 is placed at the chosen location when the second arm 22 is free of any stress.

In particular, it is preferably provided that the predefined distance condition is fulfilled when the shoe 78 is disposed in abutment against the base 14, more precisely against the bearing flange 42 and the flange 44, the dimensions of which are preferably adapted, when the manufacture, the dimensions of the spiral 1 to use. Thus, the second arm 22 is advantageously shaped and dimensioned such that it has a preload at rest, such that the shoe 78 is arranged in abutment against the base 14, to ensure the maintenance of the spiral in its service position, even in case of shock. The predefined distance is then defined by the width of the support plate 42 and the rim 44, measured from the bearing surface 40.

The bearing surface 40, the bearing pad 42, the flange 44 and the shoe 78 thus define a closed housing of rectangular cross-section for the hairspring when the second arm 22 is in its first position.

In general, it can be provided that the shoe 78 is arranged in abutment against the end turn 8 when it is positioned at the predefined distance from the bearing surface 40 or, alternatively, that a small space is preserved between them , depending on the desired effect and without departing from the scope of the present invention.

When the eccentric 84 is in its second configuration, the locking member may for example be neutralized to allow translation of the end turn 8 with reference to the base 14, or an adjustment of the active length of the hairspring 1.

In the particular case of the preferred embodiment, shown by way of nonlimiting illustration, the locking member 52 is arranged in its support (the mounting plate 62) so as to be pivotable. So, when the eccentric 84 is in its second configuration, it is sufficient to rotate the locking member 52 in the counterclockwise direction on the figure 6 to shorten the active length of the hairspring or clockwise to lengthen it.

The locking member 52 thereby performs a wheel function, without causing any damage to the balance spring 1 given the manner in which it is constructed, as previously discussed.

Moreover, it also emerges from the foregoing explanations that the introduction of the hairspring 1 on the corresponding watch movement is simplified by the characteristics of the device 12. In fact, when the eccentric 84 is in its second configuration, the end turn 8 spiral 1 can simply be deposited on the support plate 42 to take place against the bearing surface 40, the first arm 20 being spaced by elastic deformation, to clear a passage for the hairspring 1 between the locking member 52 and the bearing surface 40.

Once the end turn 8 in place to its operating position, the first arm 20 can be released to allow the locking member 52 to perform its function, by pressing the hairspring 1 against the bearing surface 40.

The marker may be adjusted by rotating the base 14 with reference to the pendulum bridge 6.

The active length of the hairspring 1 can then be adjusted by rotation of the locking member 52 in one direction or the other, before releasing the second arm 22 by rotation of the eccentric 84 so as to position one of its truncated portions facing the base 14. The shoe 78 is then positioned at the predefined distance of the bearing surface 40 and the balance-hairspring is ready for operation.

Thanks to the construction of the assembly and adjustment device of a hairspring which has just been described, we obtain such a device which is simple to assemble, which is reliable and which offers adjustment possibilities of the sprung balance very easy to implement. In particular, it should be noted that the installation of the hairspring or its adjustment can be done without causing any damage that could affect its chronometric qualities. In addition, when the second arm is spaced to release the hairspring and then replaced in the device according to the present invention, the distance separating the shoe from the bearing surface is precisely respected, by construction.

The foregoing description attempts to describe a particular embodiment by way of non-limiting illustration, and the invention is not limited to certain particular characteristics which have just been described, for example the forms illustrated and described. for the base and the arms of the assembly and adjustment device, as well as for the control members (eccentric 84 here) and locking. Many alternative embodiments can be envisaged without departing from the scope of the invention. In particular, the structure and mode of operation of the locking member may be modified by the skilled person, according to his own needs, without departing from the scope of the invention.

According to an alternative embodiment, it would for example be possible to provide, on the first arm, a control member similar to that of the second arm, and cooperating with the base, to further facilitate the introduction of the spiral in the device.

Claims (11)

1. A device (12) for assembling and adjusting a balance spring intended to cooperate with a terminal coil (8) of a balance spring (1) whereof the inner end is secured to a balance-staff (2) of a balance (4), the latter being pivoted in a balance-cock (6), the device including

   a base (14), intended to be assembled to the balance-cock (6) with an adjustable angular orientation, and comprising a substantially cylindrical support surface (40), with a radius substantially equal to the radius of the terminal coil (8), and a support sole (42) adjacent to the support surface (40), said support surface (40) and said support sole (42) defining a service position of the terminal coil (8),

   a first arm (20) extending from said base (14) and supporting a locking organ (52) for locking the terminal coil (8) arranged to keep the latter bearing against the support surface (40),

   the device (12) being characterized in that it further includes

   a second arm (22) extending from said base (14) and supporting a sabot (78) able to be arranged at a predefined distance from said support surface (40) to cooperate with the terminal coil (8), and

   a control organ (84) movable between first and second configurations and arranged such that it is able to act on the second arm (22) and deform it elastically to move the sabot (78) in reference to said base (14), said first and second configurations of said control organ (84) being associated, respectively, with a first position of said second arm (22), in which said sabot (78) is situated at a distance from said support surface (40) equal to said predefined distance, and with a second position of said second arm (22), in which said sabot (78) is situated at a distance from said support surface (40) greater than the predefined distance.
2. The device (12) according to claim 1, characterized in that said first and second configurations of said control organ (84) are stable configurations.
3. The device (12) according to claim 1 or 2, characterized in that said control organ comprises an eccentric (84) arranged on said second arm (22) such that it can be pivoted in response to an action by a user, to go from one of its configurations to the other and exert pressure on said base (14), in the second configuration, such that said sabot (78) is situated at a distance from said support surface (40) greater than the predefined distance.
4. The device (12) according to claim 1 or 2, characterized in that said control organ comprises an eccentric (84) arranged on said base (14) such that it can be pivoted in response to an action by a user, to go from one of its configurations to the other and exert pressure on said second arm (22), in the second configuration, such that said sabot (78) is situated at a distance from said support surface (40) greater than said predefined distance.
5. The device (12) according to one of the preceding claims, characterized in that said second arm (22) includes, from said base (14) toward its free end, a first substantially radial portion (26) ending with a bend (30) providing the connection with a second substantially tangential portion (34), said first and second portions (26, 34) and said bend (30) being arranged such that the elastic deformation experienced by the second arm (22), in response to a change in configuration of said control organ (84), occurs essentially at said first portion (26).
6. The device (12) according to one of the preceding claims, characterized in that said sabot (78) is arranged abutting against said base (14) in said first position of said second arm (22).
7. The device (12) according to one of the preceding claims, characterized in that said first arm (20) includes, from said base (14) toward its free end, a first substantially radial portion (24) ending with a bend (28) providing the connection with a second substantially tangential portion (32), the first and second portions (24, 32) and said bend (28) being arranged such that said first arm (20) is able to undergo an elastic deformation occurring essentially at its first portion (24).
8. The device (12) according to one of the preceding claims, characterized in that said locking organ (52) includes a knurling-roller arranged on said first arm (20) such that it is able to pivot in response to an appropriate action by a user to translate the terminal coil (8) in one direction or the other based on its rotation direction.
9. The device (12) according to claim 8, characterized in that said knurling-roller includes a substantially cylindrical portion (54) made from a synthetic material intended to be arranged bearing against the terminal coil (8) in its service position.
10. A clockwork movement provided with a device (12) for assembling and adjusting a balance spring according to any one of the preceding claims.
11. A timepiece including a clockwork movement according to claim 10.

Images