CH715438A1 - Mechanical oscillator and clock movement including it. - Google Patents

Abstract

The invention relates to a mechanical oscillator (1) for a timepiece comprising: • a suspended balance (3) arranged to oscillate around a geometric axis of rotation (9), • a plurality of elastic systems (5) arranged in series and connecting said balance (9) to an attachment member (7) arranged to fix said oscillator (1) to a structural element that comprises said timepiece. Each elastic system (5) comprises an even number of at least four external frames and at least two internal connecting elements, each frame carrying two elastic elements each extending between said frame and one of said internal connecting elements. Each internal connecting element is connected to the two elastic elements carried by one of said frames as well as to an elastic element adjacent to each of the frames of the same elastic system (5) located on either side of said one frame. . Each of said elastic systems (5) is fixed to each elastic system (5) adjacent thereto by means of one of two of its frames, said frames being nonadjacent to one another. The invention also relates to a watch movement comprising such a mechanical oscillator.

Description

Technical area

The present invention relates to the field of watchmaking. It relates, more particularly, to a mechanical oscillator devoid of pivot and comprising a pendulum suspended from the frame by means of a plurality of elastic systems.

State of the art

Document EP 2 273 323 describes an oscillator of the aforementioned type, in which a pendulum is suspended from a frame element by elastic systems arranged in series. The latter each include a pair of blades extending in "V" between a rigid central part and a frame in an arc, and serve to provide the restoring torque for the balance as well as to support the latter. In the upper level of this construction, the frame is arranged to be screwed onto a frame element such as a plate or a bridge, and the rigid central part is fixed to that of the adjacent level. The frame of this last level is in turn fixed to the frame of the next elastic system, which is fixed by its rigid central part to the subsequent elastic system. This sequence continues until the balance, which is fixed at its center to the rigid central part of the last elastic system.

In this arrangement, several of the elastic systems are linked together by their rigid central parts, and the balance is also fixed to the rigid central part of the last elastic system. Consequently, the angular rigidity of the suspension of the mass, considered along the two axes perpendicular to the axis of rotation of the mass, is not optimal, and the latter can thus tilt slightly, in particular in the event of a tending angular shock to rotate the pendulum along an axis substantially perpendicular to the axis of rotation of the pendulum.

Furthermore, during oscillations, the shear generated in the central links is relatively high, which increases the risk of breakage of these interfaces.

Finally, we note that each individual elastic system is extremely unbalanced around the virtual axis of rotation, which gives rise to unwanted parasitic movements and forces.

The object of the invention is therefore to provide a mechanical oscillator in which the above-mentioned faults are at least partially overcome.

Disclosure of invention

More specifically, the invention relates to a mechanical oscillator for a timepiece comprising a suspended balance, of any shape, arranged to oscillate around an axis of geometric rotation, that is to say say a virtual axis devoid of conventional shaft and pivots. A plurality of elastic systems arranged in series connect said balance to a fastening member arranged to fix said oscillator directly or indirectly to a structural element that comprises said timepiece, such as a fixed frame element, a tourbillon cage or carousel or the like. To this end, the elastic systems have a stiffness considered parallel to the axial direction which is sufficient to suspend and to support the pendulum independently of the orientation of the system relative to the direction of the gravity vector, and an elasticity around said axis of rotation adapted to allow the pendulum to oscillate in rotation.

According to the invention, each elastic system comprises an even number of at least four external frames (that is to say four, six, eight or even more) and at least two internal connecting elements. Each frame carries two (or even more) elastic elements (elastic blades, combinations of rigid bars and blades or collars, or the like which ensure the elasticity of the elastic element considered as a whole) each extending between said frame and the 'one of said interior connecting elements.

Each interior connecting element is connected to the two elastic elements carried by one of said frames, as well as to an elastic element adjacent to each of the other frames of the same elastic system located on either side of said frame considered. .

In addition, each of said elastic systems is fixed to each elastic system adjacent thereto at the level of one of its frames out of two (these frames being non-adjacent to each other), for example by the intermediate tenons, pins, studs, screws, welding, bonding or the like, these means being arranged to make mutually integral the frames in question. In other words, each elastic system which is adjacent to a single other is fixed to this other by a frame out of two, and each elastic system which is located between two others is fixed on the one hand to a first of these other systems by one in two managers, and on the other hand to the other of these other systems by the other half of their managers.

By these means, each elastic system can be better balanced than those of the prior art and, since the elastic systems are connected in series by their frames, the force thus transmitted during the oscillations is far from the center of rotation and generates therefore significantly less shear in the connections between elastic systems.

Advantageously: <tb> • <SEP> said pendulum is connected to one of two frames of the adjacent elastic system, these said frames not being directly adjacent to one another, the other frames interposed between those fixed to the pendulum therefore being free to oscillate relative to the latter; said fastening member is connected to one of two frames of the adjacent elastic system, these said frames not being directly adjacent to one another, the other frames interposed between those fixed to the member d 'fastener therefore being free to oscillate relative to the fastener.

In the case where the oscillator comprises at least three of said elastic systems, each frame belonging to each intermediate elastic system (that is to say each elastic system which is not immediately adjacent to the balance or to the fastening member) is connected to a frame of one or other of the elastic systems adjacent thereto, half of the frames of said elastic system considered being connected to one frame out of two of another elastic system located opposite a first side of the elastic system considered (that is to say the first elastic system adjacent thereto), the other frames that comprise said elastic system considered being connected to one frame out of two of another elastic system located opposite the second side of the elastic system considered (that is to say the second elastic system adjacent thereto), said frames of the elastic system considered being connected alternately to one or the other of said s adjacent elastic systems, by their frames (that is to say that the frames of the elastic system considered are linked, by an alternating succession, to the corresponding frames of the first or of the second adjacent elastic system).

Advantageously, each elastic system is oriented by an angle of (360 / N) ° around said axis of rotation relative to the adjacent elastic system, N being the number of frames that each of said elastic systems considered individually. So for four frames per elastic system, the relative orientation angle is 90 °, for six frames 60 °, for eight frames 45 °, etc.

Advantageously, each elastic element comprises a substantially rigid central bar, a first flexible blade extending between a first end of said bar and one of said interior connecting elements as well as a second flexible blade extending between a second end of said bar, opposite said first end, and one of said frames. Of course, the smallest dimension of the section of said blades is preferably oriented perpendicular to said axis of rotation in order to provide elasticity and rigidity in the desired directions, in order to obtain the operation described above. This configuration of elastic element gives it a stiffness (that is to say a relationship between the angular displacement deforming this elastic element and the torque associated therewith) substantially constant as a function of the angle of rotation of the balance, in in any case more constant than other configurations. Alternatively, the elastic elements can be formed as simple blades, no center bar being present.

Advantageously, each of said interior connecting elements is connected exclusively to frames of the same elastic system by means of the corresponding elastic elements. In other words, no direct connection between an internal connection element of an elastic system and an internal connection element of the adjacent elastic system is present, the only connections between the elastic systems being at the level of the frames as described below. -above.

Advantageously, the oscillator further comprises a rod extending axially from said balance in the direction opposite to said elastic systems, said rod being arranged to take place with play in an opening provided in a structural element of said timepiece , no contact between the rod and the opening being present during normal operation of the oscillator. In the event of an impact having a radial component, the rod can thus come into contact with the walls of said opening, which limits the radial movement of the balance and reduces the probability that the elastic systems are damaged. If the opening also defines an axial stop for the rod, a shock tending to distance the balance from the elastic system can also be absorbed by limiting the movement of the balance in this direction.

Advantageously, the oscillator further comprises a screw axially screwed into the end of said rod, the head of said screw being arranged to come into contact with a stop integral with said structural element in the event of impact in an axial direction, in particular in the event of an impact tending to bring the balance closer to the elastic systems. In the case of an axial conc in the other direction, the rod can also abut against a corresponding axial stop. Consequently, in the event of an impact in any direction, the oscillator is protected since the travel of the balance is limited in any direction.

Alternatively, the oscillator may include a circlip or a washer integral in translation with said rod and arranged to come into contact with a stop integral with said structural element, and this in the event of an impact in an axial direction. This stop can be rigid or flexible.

Alternatively, said rod has a circumferential groove arranged to cooperate with a stop that carries said structural element, and in the event of impact in an axial direction. Again, this stop can be rigid or flexible. Said groove can be machined in the rod, or can be constituted by a gap between two rings fixed on the latter.

Advantageously, said balance is able to perform oscillations having an amplitude of at least 15 °. With an amplitude of at least 30 °, the oscillator is thus compatible with conventional escapements, such as for example escapements with Swiss or English anchor, detent, Omega-Daniels, or the like. Of course, the amplitude can be at least 60 °, at least 90 °, or even more.

Advantageously, each elastic system 5 has a rotational symmetry of (720 / N) °, N being the number of frames that each elastic system comprises.

Advantageously, the mechanical oscillator can consist of two individual oscillators as described above, arranged upside down and comprising a common balance. The latter may consist of a single pendulum, or of two sub-pendulums integral in rotation with one another, for example by means of a rod extending substantially along the axis of rotation. , by pillars connecting the serges of the two sub-balancers, or the like.

Advantageously, at least some of said elastic elements are made of silicon provided with a layer of silicon oxide on at least some (preferably all) of their outer surfaces. This layer makes it possible to modify the thermal coefficient of the Young's modulus of the elastic elements and thus to compensate for running errors due to the effects of temperature variations on the materials of the elastic systems and / or of the balance.

Brief description of the drawings

Other details of the invention will appear more clearly on reading the description which follows, made with reference to the accompanying drawings in which: Fig. 1 is an isometric view, on the attachment member side, of a mechanical oscillator according to the invention in assembled state; Fig. 2 is a side isometric view of the mechanical oscillator of FIG. 1; Fig. 3 is an isometric view, on the balance side, of the mechanical oscillator of FIG. 1; Fig. 4 is an isometric view of the pendulum of the oscillator of FIG. 1; Fig. 5 is an isometric view of one of the elastic systems of the oscillator of FIG. 1; Fig. 6 is an isometric view, on the attachment member side, of the pendulum and of the adjacent elastic system y of the oscillator of FIG. 1; Fig. 7 and 8 are isometric views of tenons used to connect the frames of one of the elastic systems to its neighbors; Fig. 9 is an isometric view of the attachment member and the associated elastic system of the oscillator of FIG. 1; Fig. 10 is an exploded isometric view of the oscillator of FIG. 1; Fig. 11 is an isometric view of two adjacent elastic systems of the oscillator of FIG. 1; Fig. 12 is an isometric cut view of the oscillator of FIG. 1 as well as of a part of the watch movement in which the oscillator is integrated; Fig. 13 is a view similar to that of FIG. 12, part of which has been enlarged, illustrating a variant of the shock protection arrangement; Fig. 14 is an enlarged isometric view of another variant of an anti-shock arrangement; Fig. 15 is yet an enlarged isometric cutaway view of yet another variant of an anti-shock arrangement; Fig. 16 is yet another enlarged isometric view of yet another variant of an anti-shock arrangement; and Fig. 17 is an isometric view cut from another variant of an oscillator according to the invention.

Modes of Carrying Out the Invention

In the following description, the term "rigid" means that an element is not likely to deform substantially during normal operation of the oscillator, in at least one given direction. Without indication of such a direction, a "rigid element" is considered to be rigid in any direction. The term "elastic" means on the other hand that an elastic deformation of an element is desired during said operation, also in at least one given direction, this deformation having a desired effect on the operation of the oscillator. If an element is rigid in a first direction and elastic in a second direction, this will be clearly indicated in the text. Furthermore, in order not to overload the figures, the set of reference signs does not appear on each drawing. Finally, we note that, in the absence of any other explicit indication to the contrary, the spatial relationships between elements are defined by default when the oscillator is at rest, and the axial direction is determined relative to the axis of rotation 9 .

Figures 1 to 3 illustrate a mechanical oscillator 1 according to the invention, in the assembled state. This oscillator 1 comprises a balance 3, which provides the inertia which, in cooperation with the elasticity of a plurality of elastic systems 5, determines the frequency of oscillation of the oscillator 1 when the latter is in operation, it that is to say when it is set in oscillation. These elastic systems 5 are arranged in series so as to connect the balance 3 to a fastening member 7, the latter being arranged to be fixed directly or indirectly (for example by means of an intermediate piece) to a fixed element. of a timepiece such as a bridge, a plate or the like or to a tourbillon cage. In this way, the pendulum 3 is suspended and can pivot substantially around a non-physical axis of rotation 9, that is to say around a virtual, geometric axis and not around a shaft mounted between bearings conventional. Oscillator 1 is thus devoid of pivots, which reduces friction and improves its quality factor compared to a conventional balance-spring oscillator.

The pendulum 3 of the illustrated embodiment, which is shown in isolation in Figure 4, is formed of a substantially rigid frame defining a peripheral serge 3a and a central hub 3b, these two elements being interconnected by a plurality of arms 3c. Additional arms 3d extend in cantilever from the hub 3b in the direction of the twill 3a. The serge 3a as well as the additional arms 3d carry masses 3f, determining the inertia of the pendulum 3. By varying the inertia with respect to the axis of rotation 9 of the masses 3f carried by the additional arms 3d and / or those carried by the serge 3a, the resonant frequency of the oscillator 1 can be adjusted in a known manner. Alternatively, by varying the rigidity of the elastic elements 5b (for example by removing material via a laser), the resonance frequency of the oscillator can also be varied.

The hub 3b carries a plate 3g (see FIG. 3) fixed in the central opening of the hub 3b by means of an intermediate piece 3j (see FIG. 12) and carries a rod 3k extending axially in direction opposite to elastic systems 5. The operation of this rod 3k will be described below in the context of FIG. 12.

The plate 3g carries a pin 3h as well as an anti-overturning system 3i in accordance with those of document EP 3 037 894. However, the balance 3 as well as the plate 3g, can take any known form, suitable to cooperate with an exhaust of any kind, such as for example an English or Swiss anchor escapement, a detent escapement, an Omega-Daniels exhaust or the like. As regards the twill 3a, the latter can be complete, split, or partial (for example by having only two sections in the form of a bar or in an arc of a circle as in the document EP 2 273 323 mentioned above).

As mentioned above, the pendulum 3 is connected to the attachment member 7 via a plurality of elastic systems 5, arranged in series. In the illustrated embodiment, the oscillator 1 comprises four of these systems 5, but the number can vary for example between two and eight or even more.

Figure 5 illustrates one of these elastic systems 5 in insulation. The latter comprises four rigid frames 5a, each in an arc. These frames are each connected via a pair of elastic elements 5b to internal connecting members 5c, said elastic elements 5b fixed to each individual frame 5a making an acute angle between them preferably between 45 ° and 75 °, more preferably between 50 ° and 70 °. In the illustrated embodiment, the four frames 5a are substantially identical and extend over the same angle, and the elastic system 5 has a rotational symmetry of 180 °. In this way, the angle formed between the elastic elements 5b of each frame 5a is also substantially identical. However, it is possible to vary these angles, for example by opposite pairs of frames. Note also that the extension of each elastic element 5 preferably intersects the axis of rotation 9 when the oscillator is at rest.

The elastic elements 5b of the illustrated embodiment each consist of a rigid bar 5d middle as well as a pair of elastic blades 5f extending on either side between the rigid bar and, of a share one of the frames 5a, on the other hand an inner connecting element 5c. The elastic elements 5b are arranged to have elasticity in bending in the plane of the elastic system 5, as well as to be substantially rigid in bending perpendicular to said plane. In this way, the stiffness of the elastic element 5b perpendicular to said plane is at least ten times, preferably at least a hundred times, that in said plane, the smallest dimension of each blade 5f being in this plane and therefore perpendicular to l axis of rotation 9. This form of elastic element 5b has an angular stiffness which is substantially constant as a function of the angle of rotation of the balance, that is to say that its coefficient of elasticity remains substantially invariant during oscillations.

Alternatively, the elastic elements 5b can each take the form of a single blade, as is the case in document EP 2 273 323, or can take the form of any kind of bending element equivalent such as for example neck arrangements located on either side of the rigid 5d bar. Neither is it necessary for the elastic elements 5b to be straight: in fact, they can take a large number of ad hoc shapes according to the needs of those skilled in the art, in particular curves.

The internal connecting members 5c are separated from each other by a slot 5g and are each fixed to four adjacent elastic elements 5b, the two of which in the middle are associated with one of the frames 5a, and the two others each belong to a corresponding adjacent frame 5a, the latter frames 5a being located on either side of the first frame 5a mentioned.

In order to better illustrate this aspect of the elastic system 5, the four frames 5a and their corresponding blades have been indicated by the letters "A", "B", "C" and "D" in FIG. 5.

Therefore, a first of the inner connecting members 5c is integral with a single elastic element 5b belonging to the frame A, the two elastic elements 5b of the frame B, as well as a single of the elastic elements 5b of the frame C , according to this sequence. In the same way, the other internal connecting member 5c is integral with the other elastic element 5b of the frame C, with the two elastic elements 5b of the frame D, as well as with the other elastic element 5b of the frame A.

Even if each elastic system 5 as illustrated has four frames 5a each associated with two elastic elements 5b, one can also provide six or even eight, which will increase the number of internal connecting elements 5c to three or four respectively, each interior connecting element 5c remaining associated with four adjacent elastic elements 5b in the manner described above. For this purpose, the rotational symmetry of each elastic system 5 is (720 / N) °, where N is the number of frames 5a per elastic system 5.

As mentioned above, the elastic systems 5 are connected in series between the balance 3 and the fastening member 7, as explained in detail below.

Balance side 3, the latter is fixed to two opposite frames 5a of a first elastic system 5 by means of pins 11 (see in particular Figure 6) which not only ensure the fixing of these components one by relative to the other, but also a predetermined separation between the balance 3 and the elastic system 5.

These pins 11 can take various forms, including two different and nonlimiting examples are illustrated in Figures 7 and 8, but it is also possible to fix the frames 5a to each other by any spacers, whatever the additional parts, or parts made of material with the frames 5a.

Figure 7 illustrates a first stud 11 which is in particular fabricable from a plate of micro-machinable material such as silicon. To this end, the pin 11 has two heads 11a extending in two opposite directions, and separated by a spacer 11b of rectangular section, and can be formed by engraving (laser, chemical (for example DRIE), by dry process. .), electroforming (for example LIGA or other), by an additive process (3D printing), or any other similar process. The heads 11a are arranged to be fixed in corresponding openings having complementary shapes provided in the elements to be bonded by driving, gluing, welding, clipping or the like. The spacer 11b serves to define a predetermined separation between the two elements thus fixed to each other, so that the frames 5a, the elastic elements 5b and the internal connecting elements 5c do not come into contact.

Figure 8 illustrates a conventional stud 11, of circular section, which can be machined in a conventional manner and which does not require to be described in detail. Of course, its heads 11a as well as its spacer 11b fulfill the same functions as those of the stud 11 of FIG. 7. Tenons 11 of this shape can also be fixed in the complementary openings by means of hunting, gluing, welding, clipping or similar.

Alternatively, the pins 11 may have come integrally with some of the frames 5a.

Turning now to the side opposite the balance 3, Figure 9 illustrates the fastener 7, which is intended to be fixed to a fixed structural element of a timepiece, such as a bridge or a platinum, or to a movable structural element such as a tourbillon or carousel cage or the like. In the illustrated embodiment, this attachment member comprises a pair of tongues 7a provided with a plurality of openings intended to receive positioning pins, fixing screws, screw feet or the like, as well as a rigid ring 7b. Of course, other forms of attachment devices are possible.

Although it is possible to fix two frames 5a of the last elastic system 5 to this ring in a similar manner to the attachment of the pendulum to the elastic system 5 adjacent thereto, it is advantageous to form said last elastic system 5 in one piece with said fastening member 7. For this purpose, two of the frames 5a are formed integrally with the ring 7b, these said frames 5a being of course opposite one with respect to the other. The two other frames 5a which are between the fixed frames 5a are free and can thus move in the plane of this elastic system 5. In so doing, the thickness of the oscillator 1 can be reduced to a minimum, and each frame 5a which can move is located between the two fixed frames 5a.

Note also that it is also possible that two of the frames 5a of the last elastic system 5 can act themselves as fasteners, by being fixed directly or indirectly to a structural element of the movement, or by being integrated into this structural element.

FIG. 10 illustrates the oscillator 1 in exploded view in order to illustrate more clearly the arrangement in series of the various elastic systems 5.

In this figure, the level of the attachment member has been indicated as "level 1", that immediately adjacent to the pendulum as "level 4", and the sequence of intermediate levels has been numbered as indicated in the figure . In addition, the suffixes A, B, C, D were used to identify the specific frames, as indicated in Figure 5.

We start with the elastic system 5 of level 1 which, as a reminder, came integrally with the fastening member at the level of the frames 5aB and 5aD. The other two frames 5aA and 5aC, which are free to move in their plane relative to the fastening member 7a, are fixed to the two adjacent frames 5aB and 5aD of the next elastic system 5, by means of the pins 11 mentioned above. This last elastic system 5 is oriented at 90 ° relative to that integrated into the attachment member and this when the oscillator 1 is at rest, so that the slots 5g between the internal connecting members 5c of each level is oriented 90 ° to each other.

The other two frames 5aA and 5aC of level 2 are in turn fixed by means of pins 11 to the two adjacent frames 5aB and 5aD of the next elastic system 5 of level 3, the other two frames 5aA and 5aC of this level being fixed in turn to the frames 5aB and 5aD respectively of level 4. Finally, the other frames 5aA and 5aC of level 4 are fixed to the balance 3. We note that we consider the elastic systems 5 of levels 2 and 3 as being elastic systems 5 intermediate, since each of these elastic systems 5 is adjacent to two others located on either side in the axial direction.

Figure 11 illustrates more clearly the relative orientation of two adjacent levels of elastic systems 5, including levels 4 and 3. The orientation of this view is the opposite of that of Figure 10, and for this reason level 4 is above level 3 in this figure. It is clearly seen how the slots between the internal connecting members 5c of each adjacent level are oriented at 90 ° relative to each other, since the two elastic systems 5 are oriented at 90 ° with respect to the 'other.

Note also that there is no connection between the different levels at the center of the elastic systems 5, the internal connecting members 5c of a given level being free relative to those of the adjacent level. In fact, in the proposed construction, the only connections between the levels are at the level of the frames 5a.

In the case where each elastic system comprises six frames 5a (and thus three internal connecting members 5c), the angular relationship between each elastic system 5 and the adjacent elastic systems 5 is 60 °. In the same way, in the case of eight frames per level, the angular relationship is 45 °, the same considerations also apply to it. More generally, for N frames, the angular relationship between adjacent elastic systems is at the rate of (360 / N) °, thanks to the rotational symmetry of (720 / N) ° of each elastic system 5.

In the illustrated embodiment, the number of elastic systems 5 is four, but the number can vary between two and eight or even more. The arrangement of four elastic systems 5 allows an amplitude of approximately 100 ° to 120 ° for the oscillations of the balance 3, a lower number of elastic systems 5 generating oscillations of smaller amplitude, a higher number causing oscillations of greater amplitude.

Figure 12 illustrates in cut isometric view, the oscillator 1 described above, mounted on a bridge 11 secured to a plate 13 of a clockwork movement. This plate 13 also carries a gear train 15 and an exhaust 17 in a known manner. In order to protect the oscillator 1 from impact at least in certain directions, the free end of the cylindrical rod 3k takes place in an opening 19a provided in a ring 19 fixed in the plate 13 by driving out, bonding, welding or the like. Alternatively, this opening can be formed directly in the plate 13. The opening 19a can be blind or through, and in the illustrated embodiment it is through but has a shoulder 19c against which the end of the rod 3k can abut in case of axial shock tending to move the balance 3 away from the elastic systems 5. In other construction variants not shown, the ring 19 (or the aforementioned opening formed directly in a structural element) may be provided in a bridge, an element a tourbillon or carousel cage, or any other structural element, whether fixed or mobile. This also applies to the other variants described below.

When the oscillator is at rest or operating normally, a clearance exists between the rod 3k and the interior walls of the opening 19a, these two elements therefore not coming into contact. However, in the event of a radial, axial or rotation impact around an axis other than the axis of rotation 9 of the oscillator 1, the rod 3k abuts against at least one of the internal walls of the opening 19a, in particular against its cylindrical wall or its shoulder 19c. In doing so, the travel of the balance 3 is limited, the mechanical stresses generated in the oscillator are limited and the risk of rupture of the elastic elements 5b is also minimized. However, this arrangement does not provide any protection against an axial shock tending to bring the balance 3 closer to the elastic systems 5, that is to say upwards according to the orientation of this figure.

FIG. 13 illustrates a variant of an anti-shock arrangement which differs from that of FIG. 12 in that a screw 3p is screwed axially in the free end of the rod 3k, the screw not coming into contact with the walls of the opening 19a during normal operation of the oscillator 1. The opening 19a in the ring 19 defines a shoulder 19c against which the head of the screw 3p abuts in the event of an axial shock tending to bring the balance closer 3 of the elastic systems 5. Again, during normal operation of the oscillator, neither the rod 3k nor the screw 3p comes into contact with any surface of the opening 19a or the shoulder. The travel of the oscillator is thus limited in the event of impact along any axis of translation or rotation, with the exception of the axis of rotation 9 of the oscillator 1.

FIG. 14 further illustrates a variant of an anti-shock arrangement, in which the rod 3k is provided with a circlip 3m which is fixed at an appropriate location, for example by clipping. Alternatively, instead of a circlip, it is possible to use a driven, glued, welded or similar washer on the rod 3k. The axial movement of the balance 3 is limited on the one hand by the external surface of the ring 19 which is opposite the balance 3, and on the other hand by a stop element 21 which is integral with a frame element and of which the end 21a is superimposed on the circlip 3m. This stop element can take any form, but can for example be a rocker mounted on the frame element. This rocker can for example pivot around a pin in an angular range determined by an eccentric or by other positioning means (such as for example two opposite screws), a locking device such as one or more screws or the like being able to be arranged to block the rocker in pivoting. The opening 19a in the ring 19 is cylindrical in the illustrated variant, but nothing prevents the use of a ring 19 like that of Figure 12, the opening 19a is partially closed by a shoulder 19c.

Consequently, during a radial or angular impact, the rod 3k abuts against the internal wall of the opening 19a, and during an axial impact, the circlip 3m abuts against one or the other of the surface of the ring 19 or the end 21a of the stop element 21.

FIG. 15 illustrates yet another variant of an anti-shock arrangement, where the rod 3k has a circumferential groove 3n in which the end of a stop element 21 takes place fixed to a frame element 13.

Again, when the oscillator 1 is at rest or operating normally, the rod 3k does not come into contact with either the opening 19a, or with the end 21a of the stop element 21, thanks to the play which is present between these elements.

In the event of an axial shock, a surface of the groove 3n comes into contact with said end 21a, which limits the movement of the pendulum.

Even if a simple annular ring 19 like that of FIG. 14 can be used in this variant, in the illustrated embodiment, the end 21a of the stop element 21 passes through a lateral opening 19b formed in the ring 19. If the stop element 21 has a certain elasticity in bending, the stop element 21 can be used as a shock absorber. In the event of a strong axial shock, which is sufficient to cause the stop element to flex, the latter comes into contact with one or the other of the walls of said opening 19b which are located opposite the stop element 21 to limit the movement of the pendulum 3.

FIG. 16 also illustrates a variant of an anti-shock arrangement, which differs from that of FIG. 15 in that, instead of a groove 3n machined in the body of the rod 3k, two rings 3o, 3p are chased, glued or welded on the rod 3k. These two rings 3o, 3p are separated from each other by an annular gap, which constitutes said groove 3n in which the end 21a of the abutment element 21 takes place. In the illustrated variant, the diameter of the end of the rod 3k is reduced, but it is also possible that it has the same diameter at each ring 3o, 3p.

In Figures 12-16, the oscillator 1 according to the invention has been illustrated fixed to a fixed element of the frame of a clockwork movement. However, it can alternatively be fixed to a movable structural element, such as a tourbillon or carousel cage, or to a bridge fixed in turn to such a cage.

The fastener 7, the elastic systems 5 and the frame 3a of the balance 3 are particularly suitable for manufacturing by micro-machining, on the basis of a non-metallic material.

As such, we can mention manufacturing processes by masking and engraving (wet or dry) of material plates (such as the DRIE process), laser cutting of such plates and the like. Microstructuring processes are also possible, by modifying the structure of material plates for example by laser irradiation (in particular by "femtolaser") and then the elimination of the irradiated material by chemical etching. In principle, we could even create a one-piece oscillator by applying this latter process to a block of photostructurable material such as suitable glass.

Additive manufacturing processes based on 3D printing (stereolithography, selective laser sintering, selective laser fusion, etc.) or on the formation of molds and their filling with material such as LIGA (Lithography, Galvanoformung , Abformung), sintering and the like are also possible.

As far as suitable materials are concerned, the following may be mentioned without limitation: <tb> • <SEP> Materials based on silicon, that is to say silicon itself, its nitride, its carbide or its oxide, in amorphous, polycrystalline (nanocrystalline, microcrystalline) form, monocrystalline according to n 'whatever crystallographic orientation; <tb> • <SEP> Synthetic diamonds; <tb> • <SEP> Ceramics such as alumina (ruby, corundum, sapphire), in mono- or polycrystalline form; <tb> • <SEP> Glasses, in particular photostructurable glasses as mentioned above; <tb> • <SEP> Ceramic glasses; <tb> • <SEP> Conventional metals with suitable elastic properties; <tb> • <SEP> Metallic glasses (ie amorphous metals).

These materials can also be coated, for example with silicon oxide, adamantine carbon (DLC), alumina or the like, in order to modify their mechanical, thermal or optical properties, in known manner. If the elastic systems 5 are based on silicon, an outer layer of silicon oxide can advantageously be formed on a silicon core in order to make the operation of the oscillator 1 substantially independent of temperature by modifying the thermal coefficient of the module Young of elastic elements 5b. In fact, by varying the thickness of this layer, said thermal coefficient of the Young's modulus of elastic elements can be made substantially zero, or can be made the reverse of that of silicon in order to compensate for the variations in walking generated by the thermal expansion of the pendulum. Furthermore, it is also possible to apply the teaching of document EP 2 215 531 to the elastic elements 5b of the present oscillator 1. In so doing, the manufacturer can manufacture an oscillator 1 which complies with the COSC criteria, the latter requiring precision. ± 0.6s / (j ° C).

Finally, Figure 17 illustrates yet another variant of a mechanical oscillator 1 according to the invention, which comprises two oscillators 1 as described above arranged upside down and comprising a common balance 3. These two sub-oscillators are thus coupled at the balance 3, and the assembly can alternatively be considered as a system of oscillators.

In other words, this variant comprises two oscillators 1 as illustrated in FIGS. 1 to 11 mounted in opposite directions, their individual pendulums 3 being adjacent and made integral in rotation with one another in order to form a common pendulum which is linked at the same time to each fastening member 7 by means of a corresponding elastic system 5. In this case, the individual pendulums associated with each elastic system 5 are considered to be "sub-pendulums" , their assembly constituting the common balance 3.

In the illustrated variant, each elastic system 5 is identical, and the tongues 7a of each attachment member 7 extend in the same direction. However, the two elastic systems 5 can be different, and the tongues 7a can extend in different directions.

In order to constitute said common pendulum 3, the two individual pendulums, even sub-pendulums, are made integral in rotation with one another by means of a rod 3k which extends substantially along the geometric axis of rotation 9, and is driven, glued, welded or the like to each sub-balance. However, pillars or the like extending between the serges or between other parts of the pendulums are also foreseeable. Furthermore, only one individual balance is also possible as a common balance.

This arrangement has a greater stiffness in translation, in particular along the axis 9, as well as in torsion, in particular around any axis which is not the axis of rotation 9. The movement of the balance 3 in shock is thus reduced, regardless of a translational or rotational shock.

Although the invention has been described above in connection with specific embodiments, additional variants are also possible without departing from the scope of the invention as defined by the claims.

For example, it is not mandatory that each elastic system 5 is planar, more complex shapes are also possible. The various frames 5a must also not be absolutely all of identical shape.

Claims (17)

1. Mechanical oscillator (1) for a timepiece comprising: A suspended balance (3) arranged to oscillate around a geometric axis of rotation (9), • a plurality of elastic systems (5) arranged in series and connecting said balance (9) to a fastening member (7) arranged to fix said oscillator (1) to a structural element (11) that comprises said timepiece ; characterized in that each elastic system (5) comprises an even number of at least four external frames (5a) and at least two internal connecting elements (5c), each frame (5a) carrying two elastic elements (5b) s' each extending between said frame (5a) and one of said interior connecting elements (5c), in that each internal connecting element (5c) is connected to the two elastic elements (5b) carried by one of said frames (5a), as well as to an elastic element (5b) adjacent to each of the frames (5a) of the same elastic system (5) located on either side of said one frame (5a); and in that each of said elastic systems (5) is fixed to each elastic system (5) adjacent thereto by means of one of two of its frames (5a), said frames (5a) being nonadjacent one the other. 2. Oscillator (1) according to claim 1, in which: • said balance (3) is connected to one frame (5a) on two of the elastic system (5) adjacent thereto, said frames (5a) being nonadjacent to one another; • said attachment member (7) is connected to one frame (5a) on two of the elastic system (5) adjacent thereto, said frames (5a) being nonadjacent to one another. 3. Oscillator (1) according to claim 2, wherein said oscillator comprises at least three of said elastic systems (5), each frame (5a) belonging to each intermediate elastic system (5) being connected to a frame (5a) of the '' one or other of the elastic systems (5) adjacent thereto, one frame (5a) in two of the elastic system considered being connected to a frame (5a) in two of another elastic system (5) located on a first side of the elastic system (5) considered, the other frames (5a) that comprise said elastic system (5) considered being connected to one frame (5a) on two of another elastic system (5) located on the second side of the elastic system (5) considered, said frames (5a) of the elastic system (5) considered being alternately connected to one or the other of said adjacent elastic systems (5). 4. Oscillator (1) according to one of the preceding claims, in which each elastic system (5) is oriented relative to the elastic system (5) adjacent thereto by an angle of (360 / N) ° around said axis of rotation (9), N being the number of frames that each elastic system (5) has. 5. Oscillator (1) according to one of the preceding claims, in which each elastic element (5b) comprises: • a center bar; A first flexible blade (5f) extending between a first end of said bar and one of said interior connecting elements (5c), and • a second flexible blade (5f) extending between a second end of said bar, opposite to said first end, and one of said frames (5a). 6. Oscillator (1) according to one of the preceding claims, wherein each of said interior connecting elements (5c) is connected exclusively to frames (5a) of the same elastic system via the corresponding elastic elements (5b). 7. Oscillator (1) according to one of the preceding claims, further comprising a rod (3k) extending axially from said balance (3) in the direction opposite to said elastic systems (5), said rod (3k) being arranged for take place with play in an opening (19a) provided in a structural element (13) of said timepiece. 8. Oscillator (1) according to claim 7, comprising a screw (3p) screwed axially in the end of said rod (3k), the head of said screw (3b) being arranged to come into contact with a stop (19c) integral with said structural element (13), and this in the event of an impact in an axial direction. 9. Oscillator (1) according to claim 7, comprising a circlip (3m) or a washer integral in translation with said rod (3k) and arranged to come into contact with a stop (21a, 19) integral with said structural element (13) , and this in the event of an impact in an axial direction. 10. Oscillator (1) according to claim 7, wherein said rod (3k) comprises a circumferential groove (3n) arranged to cooperate with a stop (21a) integral with said structural element (13), and this in the event of an impact according to a axial direction. 11. Oscillator (1) according to claim 10, wherein said circumferential groove (3n) is constituted by a gap formed between two rings (3o, 3p) fixed on said rod (3k). 12. Oscillator (1) according to one of the preceding claims, arranged such that said balance (3) performs oscillations having an amplitude of at least 15 °, preferably at least 30 °, preferably at least 60 ° , preferably at least 90 °. 13. Oscillator (1) according to one of the preceding claims, in which each elastic system 5 has a rotational symmetry of (720 / N) °, N being the number of frames that each elastic system (5) comprises. 14. Mechanical oscillator (1) comprising two oscillators (1) according to one of claims 1 to 6 arranged upside down and comprising a common balance. 15. Mechanical oscillator (1) according to claim 16, wherein said common pendulum consists of two sub-pendulums integral in rotation with one another. 16. Oscillator (1) according to one of the preceding claims, wherein at least some of said elastic elements (5b) is made of silicon provided with a layer of silicon oxide on at least some of their surfaces. 17. Watch movement comprising an oscillator (1) according to one of the preceding claims.