EP2884347A1 - Hairspring with device for ensuring the separation of the turns - Google Patents

Abstract

The invention relates to a hairspring (1, 11, 21, 31, 41, 51, 61, 71) comprising a blade (3, 13, 23, 33, 43, 53, 63, 73) with a polygonal section wound on itself according to several turns (8, 10). According to the invention, at least one turn (8, 10) comprises an anti-approach device (5, 15, 25, 35, 45, 55, 65, 75) of turns (8, 10) comprising at least two stops ( 7, 7 ', 17, 27, 37, 47, 57, 67, 77) mounted on the same face and projecting from the thickness (E) of said at least one turn (8, 10) of the blade (3 , 13, 23, 33, 43, 53, 63, 73), each of said at least two stops (7, 7 ', 17, 27, 37, 47, 57, 67, 77) being arranged to come into contact with the facing towards another turn (10, 8) of the blade (3, 13, 23, 33, 43, 53, 63, 73) by preventing the other turn (10, 8) from touching said at least one turn (8) during a shock.

The invention relates to the field of resonators of the balance spring - spiral type.

Description

Field of the invention

The invention relates to a hairspring intended to reduce the risk of bonding between its turns in order to improve the operation of a resonator in which said hairspring is used.

Background of the invention

It is usual in watchmaking to form spirals whose winding of the blade substantially follows the trajectory of an Archimedean spiral. However, it has been noticed that coil gluing could be generated since the use in watchmaking of new materials such as crystalline silicon.

Summary of the invention

The object of the present invention is to overcome all or part of the disadvantages mentioned above by proposing an alternative to the usual spiral which avoids the gluing of the turns together.

For this purpose, the invention relates to a spiral comprising a polygonal section blade wound on itself according to a plurality of turns, characterized in that at least one coil of the spiral comprises an anti-approach device of turns comprising at least two stops mounted on the same face and projecting from the thickness of said at least one turn of the blade, each of said at least two stops being arranged to come into contact with the face facing another turn of the blade. blade preventing the other turn to touch said at least one turn during a shock.

Advantageously according to the invention, the spiral with anti-approximation device of turns makes it possible to prevent geometrically the risk of bonding between turns by limiting the contact surface to said at least two stops.

• lesdites au moins deux butées sont distribuées sur ladite face selon un angle compris entre 80° et 170° ;
• lesdites au moins deux butées font saillies de l'épaisseur sur au moins une partie ou toute de la hauteur de la lame ;
• lesdites au moins deux butées sont chacune en forme de prisme triangulaire, semi-cylindrique ou pentagonal afin qu'une arête fasse vis-à-vis avec la face de ladite autre spire ;
• l'arête desdites au moins deux butées faisant vis-à-vis avec la face de ladite autre spire est arrondie pour offrir une pression de contact moins élevée lors d'un choc ;
• lesdites au moins deux butées sont au moins partiellement évidées afin d'ajuster l'effet de leur masse sur le balourd du spiral ;
• lesdites au moins deux butées sont montées sur ladite face du spiral à l'aide d'une base intermédiaire pour limiter l'augmentation de rigidité locale ;
• la spire interne est solidaire d'une virole agencée pour être fixée à un axe ;
• le spiral est monobloc.

According to other advantageous variants of the invention:

• said at least two stops are distributed on said face at an angle of between 80 ° and 170 °;
• said at least two abutments protrude from the thickness over at least a portion or all of the height of the blade;
• said at least two abutments are each in the form of a triangular, semi-cylindrical or pentagonal prism so that one edge faces the face of said other turn;
• the edge of said at least two abutments facing the face of said other turn is rounded to provide a lower contact pressure upon impact;
• said at least two stops are at least partially recessed in order to adjust the effect of their mass on the unbalance of the hairspring;
• said at least two stops are mounted on said face of the hairspring by means of an intermediate base to limit the increase in local rigidity;
• the inner coil is integral with a ferrule arranged to be fixed to an axis;
• the spiral is monobloc.

Finally, the invention also relates to a timepiece characterized in that it comprises at least one hairspring according to one of the preceding variants.

Brief description of the drawings

• la figure 1 est une vue partielle de dessus d'un dispositif anti-rapprochement de spires selon l'invention ;
• les figures 2 et 3 sont des vues partielles en perspective de deux exemples de dispositif anti-rapprochement de spires selon l'invention ;
• les figures 4 à 10 sont des vues partielles de dessus de modes de réalisation de dispositif anti-rapprochement de spires selon l'invention ;
• la figure 11 est une vue en perspective partielle d'une virole et du début de spire interne d'un spiral selon l'invention.

Other particularities and advantages will emerge clearly from the description which is given hereinafter, by way of indication and in no way limiting, with reference to the appended drawings, in which:

• the figure 1 is a partial view from above of an anti-approach device of turns according to the invention;
• the Figures 2 and 3 are partial views in perspective of two examples of anti-approach device of turns according to the invention;
• the Figures 4 to 10 are partial top views of coil anti-closures embodiments of the invention;
• the figure 11 is a partial perspective view of a ferrule and the beginning of inner coil of a spiral according to the invention.

Detailed Description of the Preferred Embodiments

The present invention relates to a spiral for the field of watchmaking. More specifically, the hairspring is intended to be mounted in a timepiece such as, for example, in cooperation with a beam to form a pendulum resonator - spiral forming the regulating member of the timepiece.

As explained above, it has been noticed that coil splices could be generated with the use of crystalline silicon spirals. Indeed, the heights of the turns facing each other are so smooth that adhesion can be generated simply by bringing two turns together, for example, by an impact on the timepiece. This adhesion can be further increased by contaminating the hairspring with impurities or lubricant during manufacture or wearing.

The hairspring 1, 11, 21, 31, 41, 51, 61, 71 according to the invention comprising a blade 3, 13, 23, 33, 43, 53, 63, 73 of length L, height H and thickness E forming a polygonal section, preferably rectangular, formed by the height H and the thickness E. The blade 3 is wound on itself in several turns. It is therefore understood that the face formed according to the height of the blade 3, 13, 23, 33, 43, 53, 63, 73 of a first turn vis-a-vis the opposite face of the blade on the turn immediately consecutive.

Advantageously according to the invention, in order to solve the adhesion problems explained above, at least one turn 8, 10 of the spiral 1, 11, 21, 31, 41, 51, 61, 71 comprises a device 5, 15, 25 , 35, 45, 55, 65, 75 anti-approximation of turns comprising at least two stops 7, 7 ', 17, 27, 37, 47, 57, 67, 77 mounted on the same face and projecting from the thickness E of said at least one turn of the blade, each of said at least two stops 7, 7 ', 17, 27, 37, 47, 57, 67, 77 being arranged to come into contact with the facing face. another turn of the blade 3, 13, 23, 33, 43, 53, 63, 73 by preventing the other turn to touch said at least one turn during an impact.

As illustrated in figure 1 we can see an example of spiral 1 according to the invention which is fully contracted. The figure 1 is a partial top view of an example of a device 5 anti-approximation of turns. A first turn 8 formed by the blade 3 extends along a first radius R ₁ relative to the center of the hairspring 1. A second turn 10 formed by the blade 3 extends along a second radius R ₂ relative to the center of the hairspring 1. The hairspring 1 being contracted to the maximum at figure 1 it is understood that the difference between the second radius R ₂ and the first radius R ₁ corresponds to the minimum distance D between turns 8, 10 during normal operation ( R ₂ - R ₁ = D ).

To the figure 1 it can be seen that the said at least two abutments 7, 7 'protrude from the thickness E of the blade to a depth P which leaves a gap I with respect to the minimum distance D between turns in normal operation. In addition, said at least two stops 7, 7 'are distributed on the same face of the first turn 8 at an angle α.

In the event of an impact, the anti-approach device 8, 10 prevents the second turn 10 from touching the first turn 8. In the diagram of FIG. figure 1 , the second turn 10 is represented by the turn 10 'in broken lines. It can be seen that the second turn 10 'abnormally deformed by a shock comes into contact with said at least two stops 7, 7 'so that the second turn 10' abnormally deformed remains at a safety distance S with respect to the first turn 8.

After calculation, it has been determined according to a good approximation that said at least two abutments 7, 7 ', 17, 27, 37, 47, 57, 67, 77 must be preferentially distributed on the same face of a turn at an angle α between 80 ° and 170 °. By compromise, it seems that a 90 ° angle can guarantee a satisfactory safety distance S in all the constructions of a watch winder 1, 11, 21, 31, 41, 51, 61, 71. Of course, the angle α can be modulated according to the desired applications.

According to a first example illustrated in figure 2 , the spiral 11 comprises a blade 13 provided with a device 15 anti-approximation of turns of which said at least two abutments 17 protrude from the thickness E on only a portion of the height H of the blade 13. Of course, this first example is in no way limiting as to the height and / or relative position of said at least two stops 17 with respect to the height H of the blade 13. As a second example illustrated in FIG. figure 3 it is understood in particular that the device 5 anti-approximation of turns could equally include said at least two abutments 7 protruding from the thickness E over the entire height H of the blade 3 of the spiral 1.

Of course, it may be envisaged to combine, in the same device 5, 15, 25, 35, 45, 55, 65, 75 anti-approximation of turns, said at least two stops 7, 7 ', 17, 27, 37 , 47, 57, 67, 77 of different configurations, that is to say for example to alternate stops 17 of the first example with stops 7 of the second example.

Examples of Figures 1 to 3 disclose said at least two stops 7, 7 ', 17 each in the form of a triangular prism so that an edge 9, 19 is vis-à-vis with the opposite face of another turn. It is easily understood that said at least two stops 7, 7 ', 17, 27, 37, 47, 57, 67, 77 can not be limited to such a triangular prismatic shape.

Thus according to alternatives, said at least two abutments 7, 7 ', 17, 27, 37, 47, 57, 67, 77 may be of different shape as, for example, in pentagonal prismatic form, with an edge 9, 9' , 19, 29, 39, 49, 59, 69, 79, or partially recessed, or of different arrangement as, for example, mounted on the same face of the spiral differently.

Examples of embodiments of device 5, 15, 25, 35, 45, 55, 65, 75 anti-approach of turns according to the invention will be described in reference to the Figures 4 to 10 . The first embodiment of the figure 4 is the one already illustrated at Figures 1 to 3 . It comprises a spiral 1 formed by a blade 3 provided with a device 5 anti-approximation of turns comprising said at least two abutments 7, 7 'in the form of a solid triangular prism directly protruding from the thickness E of the blade 3 with a pointed ridge 9 facing the turn immediately consecutively.

The second embodiment of the figure 5 is close to that of the figure 4 . Indeed, it comprises a hairspring 21 formed by a blade 23 provided with a device 25 anti-approximation of turns comprising said at least two stops 27 in the form of a solid triangular prism directly protruding from the thickness E of the blade 23. However, in this second embodiment, the edge 29, which faces the turn immediately consecutive, is rounded to provide a lower contact pressure during an impact.

The third embodiment of the figure 6 is close to that of the figure 5 . Indeed, it comprises a spiral 31 formed by a blade 33 provided with a device 35 anti-approximation of turns comprising said at least two stops in the form of a triangular prism directly protruding from the thickness E of the blade 33 with a rounded edge 9 which faces the turn immediately consecutive. However, in this third embodiment, said at least two stops 37 are at least partially recessed in order to adjust the effect of their mass on the unbalance of the hairspring 31.

The fourth embodiment of the figure 7 comprises a spiral 41 formed by a blade 43 provided with a device 45 anti-approximation of turns comprising said at least two stops 47 as a solid pentagonal prism directly protruding from the thickness E of the blade 43 with a sharp edge 49 who faces the turn immediately consecutively.

The fifth embodiment of the figure 8 is close to that of the figure 7 . Indeed, it comprises a hairspring 51 formed by a blade 53 provided with a device 55 anti-approach of turns comprising said at least two stops 57 in the form of a pentagonal prism directly protruding from the thickness E of the blade 53. However in this third embodiment, the edge 59 which faces the turn immediately consecutive is rounded and said at least two stops 57 are at least partially hollowed out.

The sixth embodiment of the figure 9 is close to that of the figure 4 . Indeed, it comprises a spiral 61 formed by a blade 63 provided with a device 65 anti-approximation of turns comprising said at least two stops 67 as a solid triangular prism directly protruding from the thickness E of the blade 63 with a sharp ridge 69 facing the turn immediately consecutively. However, in this sixth embodiment, said at least two stops 67 are mounted on the same face of the hairspring using an intermediate base 68 to limit the increase in local stiffness induced by the localized increase of the thickness E on the blade 63.

Finally, the seventh embodiment of the figure 10 is close to that of the figure 9 . Indeed, it comprises a hairspring 71 formed by a blade 73 provided with a device 75 anti-approximation of turns comprising said at least two stops 77 in the form of triangular prism protruding from the thickness E of the blade 73 by means of an intermediate base 78. However, in this seventh embodiment, the edge 79 which faces the turn immediately consecutive is rounded and said at least two stops 77 are at least partially hollowed out.

Of course, the present invention is not limited to the illustrated example but is susceptible of various variations and modifications that will occur to those skilled in the art. In particular, the seven embodiments are in no way limiting, that is to say that other forms and / or arrangements can be envisaged, just as it is also conceivable to combine one or more of the embodiments of the embodiments. Figures 1 to 10 on the same face of turn and / or on two consecutive turns. By way of example, said at least two abutments could be partially of cylindrical shape, that is to say have a prismatic base section in the form of a partial disk, such as, for example, semi-cylindrical.

In addition, the hairspring 1, 11, 21, 31, 41, 51, 61, 71 may also comprise an inner turn which is integral with a ferrule arranged to be fixed to an axis as illustrated in the example of FIG. figure 11 .

At this figure 11 it is possible to partially see a hairspring 1 formed by a single blade 3, the inner turn 2 of which is provided with a device 5 for preventing windings with at least two stops 7, 7 'in the form of a triangular prism protruding from the lug. E thickness of the blade 3, the inner coil 2 being integral with a ferrule 4. The substantially clover-shaped ferrule 4 has a hole 6 for, for example, to receive a balance shaft.

On reading the above examples, it will be understood that the hairspring 1, 11, 21, 31, 41, 51, 61, 71 may be one-piece, that is to say that the blade 3, 13, 23, 33 , 43, 53, 63, 73 is formed without discontinuity of material. Such a spiral 1, 11, 21, 31, 41, 51, 61, 71 may be formed based on a material comprising silicon, that is to say, for example, silicon monocrystalline, silicon polycrystalline, doped monocrystalline silicon, doped polycrystalline silicon, silicon carbide doped or not doped silicon nitride or not doped silicon oxide or not such as quartz or silica. Indeed, the anisotropic etching of such materials can be carried out wet or dry.

Claims (12)

Spiral (1, 11, 21, 31, 41, 51, 61, 71) having a blade (3, 13, 23, 33, 43, 53, 63, 73) with polygonal section wound on itself in several turns ( 8, 10), characterized in that at least one turn (8, 10) comprises an anti-approach device (5, 15, 25, 35, 45, 55, 65, 75) of turns (8, 10) comprising at least minus two stops (7, 7 ', 17, 27, 37, 47, 57, 67, 77) mounted on the same face and projecting from the thickness (E) of said at least one turn (8) of the blade (3, 13, 23, 33, 43, 53, 63, 73), each of said at least two stops (7, 7 ', 17, 27, 37, 47, 57, 67, 77) being arranged to make contact with the face facing another turn (10) of the blade (3, 13, 23, 33, 43, 53, 63, 73) by preventing the other turn (10) from touching minus one turn (8) during a shock. Spiral (1, 11, 21, 31, 41, 51, 61, 71) according to the preceding claim, characterized in that said at least two stops (7, 7 ', 17, 27, 37, 47, 57, 67, 77) are distributed on said face at an angle ( α ) of between 80 ° and 170 °. Spiral (1, 11, 21, 31, 41, 51, 61, 71) according to claim 1 or 2, characterized in that said at least two stops (7, 7 ', 17, 27, 37, 47, 57, 67, 77) protrude from the thickness (E) over at least a portion of the height (H) of the blade (3, 13, 23, 33, 43, 53, 63, 73). Spiral (1, 11, 21, 31, 41, 51, 61, 71) according to the preceding claim, characterized in that said at least two stops (7, 7 ', 17, 27, 37, 47, 57, 67, 77) protrude from the thickness (E) over the entire height ( H ) of the blade (3, 13, 23, 33, 43, 53, 63, 73). Spiral (1, 11, 21, 31, 41, 51, 61, 71) according to one of the preceding claims, characterized in that said at least two stops (7, 7 ', 17, 27, 37, 47, 57 , 67, 77) are each in the form of a triangular, semi-cylindrical or pentagonal prism so that a ridge (9, 9 ', 19, 29, 39, 49, 59, 69, 79) faces with the face of said other turn (10). Spiral (1, 11, 21, 31, 41, 51, 61, 71) according to the preceding claim, characterized in that the edge (9, 9 ', 19, 29, 39, 49, 59, 69, 79) at least two stops (7, 7 ', 17, 27, 37, 47, 57, 67, 77) facing the face of said other turn (10) are rounded to provide less contact pressure high during a shock. Spiral (1, 11, 21, 31, 41, 51, 61, 71) according to one of the preceding claims, characterized in that said at least two stops (7, 7 ', 17, 27, 37, 47, 57 , 67, 77) are at least partially recessed in order to adjust the effect of their mass on the unbalance of the hairspring (1, 11, 21, 31, 41, 51, 61, 71). Spiral (1, 11, 21, 31, 41, 51, 61, 71) according to one of the preceding claims, characterized in that said at least two stops (7, 7 ', 17, 27, 37, 47, 57 , 67, 77) are mounted on said face of the hairspring by means of an intermediate base (68, 78) to limit the increase in local rigidity. Spiral (1, 11, 21, 31, 41, 51, 61, 71) according to one of the preceding claims, characterized in that the inner coil is integral with a ferrule (4) arranged to be fixed to an axis. Spiral (1, 11, 21, 31, 41, 51, 61, 71) according to one of the preceding claims, characterized in that the spiral (1, 11, 21, 31, 41, 51, 61, 71) is piece. Spiral (1, 11, 21, 31, 41, 51, 61, 71) according to one of the preceding claims, characterized in that the spiral (1, 11, 21, 31, 41, 51, 61, 71) is formed of a material having silicon. Timepiece characterized in that it comprises at least one hairspring (1, 11, 21, 31, 41, 51, 61, 71) according to one of the preceding claims.

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