EP2656150A2

EP2656150A2 - Assembly of a component which does not have a plastic domain

Info

Publication number: EP2656150A2
Application number: EP11787857.9A
Authority: EP
Inventors: Thierry Conus; Marco Verardo; Igor Saglini; Frédéric Kohler
Original assignee: ETA SA Manufacture Horlogere Suisse
Current assignee: ETA SA Manufacture Horlogere Suisse
Priority date: 2010-12-22
Filing date: 2011-11-22
Publication date: 2013-10-30
Anticipated expiration: 2031-11-22
Also published as: US9128463B2; WO2012084384A2; US20130286795A1; JP2014501923A; CN103299245A; JP5671155B2; HK1189281A1; EP2656150B1; EP2469353A1; TW201240763A; TWI564107B; WO2012084384A3; CN103299245B

Abstract

The invention relates to an assembly (2, 12, 22, 62) of an axially extending member (7, 17, 27, 67) made of a first material in the opening (8, 18, 28, 68) of a component (1, 3, 61) made of a second material which does not have a plastic domain. According to the invention, the component (1, 3, 61) has perforations (6, 16, 26, 26', 26'', 26''', 46, 46', 66) forming elastic deformation means distributed around the opening (8, 18, 28, 68) therein. In addition, said member (7, 17, 27, 67) has a radially flared and elastically and plastically deformed part (4, 14, 24, 64) which radially clamps (B) the wall of said component surrounding the opening (8, 18, 28, 68) by stressing said elastic deformation means in order to join together the assembly (2, 12, 22, 62) in a non-destructive manner for said component. The invention relates in particular to the field of timepieces.

Description

Assembly of a part without a plastic domain

Field of the invention

The invention relates to an assembly of a part whose material does not comprise a plastic field with a member comprising another type of material.

Background of the invention

Current assemblies comprising a silicon-based part are generally bonded together. Such an operation requires extreme finesse of application which makes it expensive.

Summary of the invention

The object of the present invention is to overcome all or part of the disadvantages mentioned above by proposing a glueless assembly capable of securing a part whose material does not include a plastic field with a member comprising a ductile material such as, for example, a metal or a metal alloy.

For this purpose, the invention relates to an assembly of an axially extending member made of a first material in the opening of a part made of a second material having no plastic domain, characterized in that the part comprises perforations forming resilient deformation means distributed around its opening and in that said member comprises a radially elastically deformed and elastically deformed portion which radially clamps the wall of said part surrounding the opening by urging said elastic deformation means to secure the non-destructively assembling for said workpiece. This configuration advantageously makes it possible to secure the whole piece - organ without bonding with a usual member to the controlled accuracy while ensuring that the part does not undergo destructive efforts even if it is formed, for example, from silicon.

According to other advantageous features of the invention:

the outer wall of the flared portion is substantially of a shape corresponding to the opening of the part in order to exert a substantially uniform radial stress on the wall of the part surrounding said opening;

- the opening of the room is circular;

the opening of the part is asymmetrical in order to avoid relative displacements between the elements of said assembly;

the perforations are formed at a distance and around the opening by two series of diamond-shaped holes distributed in staggered rows in order to form beams divided into secant Vs;

the perforations comprise, between the first two series and the opening, a third series which is formed of holes in the form of a triangle and distributed in staggered rows with one of the first two series in order to form distributed X-shaped beams;

- The part has slots for communicating the third set of holes with the opening;

the perforations are formed at a distance and around the opening by a first series of oblong holes distributed in staggered rows with a second series of triangular shaped holes, the second series being the closest to the opening, each triangular shaped hole; communicating with the opening by a notch to form radially movable beams according to the thickness of the oblong holes; the perforations comprise a third series of holes in the form of a triangle, each hole of the third series being distributed between two triangular holes of the second series and communicating with the opening by a slot to form beams with two independent arms movable radially according to the thickness of the oblong holes and tangentially according to the thickness of the slots;

- The series of holes extend over a width between 100 μιη and 500 μιη from the wall of the room surrounding the opening;

- The opening has a section between 0.5 and 2 mm.

In addition, the invention relates to a timepiece characterized in that it comprises an assembly according to one of the preceding variants.

Finally, the invention relates to a method for assembling an axially extending member made of a first material in a part made of a second material that does not comprise a plastic field, said method comprising the following steps:

a) forming the part with an opening and cut-outs distributed around the opening to form elastic deformation means;

b) introducing without constraint, in the opening, a flared portion radially of said member;

c) elastically and plastically deforming the flared portion of said member in the opening by axial approximation of two tools respectively at the upper and lower portions of said flared portion in order to exert a radial stress against the wall of the part surrounding the opening by soliciting said elastic deformation means of the workpiece to allow the assembly to be non-destructively joined to said workpiece.

This method advantageously makes it possible to radially fasten the member and the workpiece without any axial force being applied to the workpiece. Indeed, advantageously according to the invention, only a radial elastic deformation is applied to the workpiece. Finally, such a method makes it possible to secure the whole piece - organ by adapting to the manufacturing dispersions of the various constituents. According to other advantageous features of the invention:

- The outer wall of the flared portion of said member in the opening is substantially shaped corresponding to the opening of the part to exert a substantially uniform radial stress on the wall of the part surrounding the opening;

- the opening of the room is circular;

during step b), the difference between the section of the circular opening and the external section of the flared portion of said member in the opening is about 10 μιη;

during step c), the deformation exerts a tightening of between 8 and 20 μιη;

- In steps b) and c), the flared portion of the member in the opening is held in the opening with one of the two tools;

the second material is formed based on silicon;

the first material is formed based on metal or metal alloy;

the piece can be, for example, a watch mobile, a watch anchor, a watch winder, a resonator or else a MEMS.

Brief description of the drawings

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:

- Figure 1 is a partial schematic view of a watch movement comprising three assemblies according to the invention;

FIG. 2 is a partial schematic view of a watch hairspring comprising a fourth assembly according to the invention; FIGS. 3 to 6 are views of variants according to a first embodiment of elastic deformation means according to the invention;

FIGS. 7 and 8 are views of variants according to a second embodiment of elastic deformation means according to the invention;

- Figures 9 to 1 1 are schematic representations of successive steps of the assembly method according to the invention.

Detailed Description of the Preferred Embodiments

As explained above, the invention relates to an assembly and its method for joining a fragile material, that is to say not having a plastic domain such as a material based on silicon, with a ductile material such as a metal or a metal alloy.

This assembly was designed for applications in the watchmaking field. However, other areas can perfectly be imagined as including aeronautics, jewelry, automotive or the arts of the table.

In the field of watchmaking, this assembly is made necessary by the growing share of fragile materials such as those based on silicon, quartz, corundum or more generally ceramic. One can for example consider forming the hairspring, the balance, the anchor, bridges or even mobiles such as exhaust wheels totally or partially based on fragile materials.

However, the fact of always being able to use usual steel axes whose production is controlled, is a constraint that is difficult to reconcile with the use of parts that do not include a plastic field. Indeed, during tests carried out, the driving of a steel shaft is impossible and systematically breaks the fragile parts, that is to say not having a plastic field. For example, it has been found that the shear generated by the entry of the metal axis into the opening of a silicon part breaks the latter systematically. This is why the invention relates to an assembly between an axially extending member made of a first material, for example ductile such as steel, in the opening of a part made of a second material that does not include a domain. plastic, as a silicon-based material, by deformation of a portion of the member which is mounted in the opening of said piece.

According to the invention, said member comprises a radially flaring portion and elastically and plastically deformed in order to clamp radially the wall of said part surrounding the opening by biasing its elastic deformation means to non-destructively fasten the assembly for said part.

In addition, preferably, the outer wall of the radially flaring portion of the member present in the opening is substantially of corresponding shape to the opening of the part in order to exert a substantially uniform radial stress on the wall of the piece surrounding said opening. Indeed, during the research carried out, it appeared preferable that the flared portion of the member present in the opening evenly distribute the radial stresses induced by its deformation on the wall of the room surrounding the opening.

Therefore, if the opening in the fragile part is circular, it is preferable that the outer wall of the flared part of the member present in the opening is in substantially continuous cylinder shape, that is to say without radial slot or axial opening, to avoid localized stresses on part of the wall of the room surrounding the opening which are suitable for initiating break points.

Of course, the shape of the opening in the fragile part may differ in being, for example, asymmetrical in order to avoid relative displacements between the elements of the assembly. Such an asymmetric opening can thus be, for example, substantially elliptical. This interpretation also justifies the non-use of a washer on the upper or lower part of the flared portion of the member present in the opening. Indeed, during the deformation, such a washer would transmit a portion of the axial strain force on the top (or bottom) of the fragile part. Therefore, the shear exerted in particular by the edges of the washer on the top (or bottom) of the fragile part generates in the same manner localized stresses suitable to initiate break points.

Therefore, the flared portion of the member present in the opening with a shape corresponding to the opening can be interpreted, if the section of the opening is circular, as a solid disc whose outer wall is continuous, c that is to say without groove or more generally material discontinuity. The corresponding shape of the flared portion of the member present in the opening thus allows, by elastic and plastic deformation, to generate only a substantially uniform radial stress on a maximized surface of the wall of the part around the opening.

Finally, according to the invention, the piece comprises perforations forming elastic deformation means which are distributed around and away from its opening and which are intended to absorb said radial forces to restore them once the stress of the tools released in order to, in the end, fasten the assembly non-destructively for said part.

The assembly according to the invention will be better understood in relation with FIGS. 1 to 8 presenting examples of applications in the field of watchmaking. FIG. 1 shows a watch exhaust system comprising an anchor 1 and an escape wheel 3 and in FIG. 2 a spiral 61.

In the case of Figure 1, the anchor 1 as an example comprises two assemblies 2, 12 according to the invention respectively for securing the stinger 7 and the member, here a pivot axis 17, with its rod 5 As can be seen in FIG. 1, each assembly 2, 12 has a flared portion radially 4, 14, substantially discoidal shape coming with the stinger 7 or the member 17 and cooperating with the rod 5 of the anchor 1. In addition, each assembly 2, 12 comprises perforations 6, 16 made in the rod 5 around an opening 8, 18 and which are intended to form elastic deformation means. It is therefore understood that the assembly 2, 12 is sufficiently strong not to generate relative movements between its components.

The escape wheel 3, and more generally the mobile 3, comprises, by way of example, an assembly 22 intended to secure the member, here a pivot axis 27, with the body 25 of the wheel 3. As visible in FIG. 1, the assembly 22 comprises a radially flaring portion 24, substantially discoidal in shape with the member 27 and co-operating with the body 25 of the wheel 3. In addition, the assembly 22 comprises cut-outs 26 made in the hub around an opening 28 of the wheel 3 and which are intended to form elastic deformation means.

It is therefore immediately understood that the example of the assembly 22 can be applied to any type of mobile. In addition, the member 27 may comprise, in addition to the flared portion 24, in one piece a pinion to form the finished mobile.

As illustrated in Figure 2, it is possible to fix a hairspring 61 on a member, here a balance shaft 67, with an assembly 62 according to the invention. Cut-outs 66 are formed in the ferrule 63 of the spiral 61 and a shaped disc portion 64 formed with the member 67 is mounted in the opening 68 of the ferrule 63, similarly to the explanations above.

Examples of cut-outs are shown in FIGS. 3 to 8. According to a first embodiment illustrated in FIGS. 3 to 6, the cut-outs are formed at a distance and around the opening by two series of diamond-shaped holes distributed in staggered rows. to form beams divided into V secants. FIG. 3 is a representation of the cutouts 6, 16, 26, 66 of FIGS. 1 and 2. For simplicity only the references of the wheel 3 are shown in FIG. 3. The latter shows cutouts 26 which preferentially traverse totally the thickness of the body 25 of fragile material. The perforations 26 are distributed at a distance and around the opening 28 formed, preferably, also completely through in the thickness of the body 25 of fragile material.

As seen in Figure 3, the cutouts 26 form a first set of holes 31, the farthest from the opening 28, and a second series of holes 33 which are diamond-shaped and distributed in staggered rows. It can be seen in FIG. 3 that the perforations 31, 33 thus form V-shaped beams 32 which are intersecting with one another.

In a first variant of the first embodiment illustrated in FIG. 4, the cut-outs 26 'take up the first and second series of holes 31, 33 with, in addition, a third series which, formed of holes 35 in the form of a triangle, is located between the first two series and the opening 28, that is to say the closest to the opening 28. As shown in Figure 4, the third series of holes 35 is distributed in staggered with one 33 of the first two series to form beams 34 distributed in intersecting X.

In a second variant of the first embodiment illustrated in FIG. 5, the cut-outs 26 "take up the cut-outs 26 'of FIG. 4 with, in addition, slots 36 making it possible to communicate the third set of holes 35 with the opening. 28.

Advantageously according to the invention, the series of holes 31, 33 and 35 and the slots 36 are used to form elastic deformation means capable of absorbing radial stresses, that is to say forces exerted from the center of the opening 28 to the wall of the body 25 surrounding said circular opening. Of course, the two or three series may be more or less close to each other and / or different shapes and / or different dimensions depending on the desired maximum displacement and the desired stress to deform the beams 32, 34.

By way of example, an alternative of FIG. 5 is shown in FIG. 6. It can be seen that the cut-outs 26 "'are similar to those 26" of FIG. 5, however, the three sets of holes are spaced further apart. each other. In addition, it is visible that the shapes and dimensions of both holes and slots are different. It is thus clear that the alternative of FIG. 6 modifies the rigidity of the elastic deformation means in the brittle material.

Preferably, the perforations 26, 26 ', 26 ", 26"' extend over a width of between 100 μιη and 500 μιη from the wall of the body 25 surrounding the opening 28. In addition, the slots 36 are included between 15 μιη and 40 μιη. Finally, preferably, the section of the opening 28 is between 0.5 and 2 mm.

According to a second embodiment illustrated in FIGS. 7 and 8, the perforations are formed at a distance and around the opening by a first series of oblong holes distributed in staggered rows with a second series of triangular shaped holes, the second series being the closer to the circular opening, each triangular hole communicating with the opening by a notch to form radially movable beams according to the thickness of the oblong holes.

Thus, FIG. 7 shows cutouts 46 which, preferably, completely traverse the thickness of the body 25 of fragile material. The perforations 46 are distributed at a distance and around the opening 28 formed, preferably, also completely through in the thickness of the body 25 of fragile material.

As visible in FIG. 7, the cutouts 46 form a first series of oblong holes 51 and a second series of holes 53 of shape. triangular. According to the second embodiment, the two sets of holes 51, 53 are distributed in staggered rows.

In addition, each hole 53 of triangular shape communicates with the opening 28 by a notch 57. It can be seen in FIG. 7 that the perforations 46 thus form substantially trapezoid-shaped beams 52 which are separated from each other by the notches. 57. Note also that each beam 52 is centered on an oblong hole 51 which makes each beam 52 movable radially according to the thickness of an oblong hole 51.

In a variant of the second embodiment illustrated in FIG. 8, the cut-outs 46 'take up the cut-outs 46 of FIG. 7 with, in addition, a third series of holes 55 in the shape of a triangle. In addition, each hole 55 of the third series is distributed between two holes 53 of triangular shape of the second series and communicates with the opening 28 by a slot 56. The perforations 46 'thus form beams 54 with two independent arms symmetrical and substantially L-shaped which are radially movable according to the thickness of the holes 51 oblong and tangentially according to the thickness of the slots 56 and notches 57.

Of course, as for the first embodiment, the two or three series may be more or less close to each other and / or different shapes and / or different dimensions depending on the desired maximum travel and the desired stress for deform the beams 52, 54.

Preferably, the perforations 46, 46 'extend over a width of between 100 μιη and 500 μιη from the wall of the body 25 surrounding the opening 28. In addition, the slots 56 and the notches 57 are between 15 μιη and 40 μιη. Finally, preferably, the section of the opening 28 is between 0.5 and 2 mm.

The assembly method will now be explained in relation to the schematic figures 9 to 11. For simplicity, only references of the wheel 3 are shown in FIGS. 9 to 11. According to the invention, a first step consists in forming the part 3 in a material having no plastic domain with an opening 28 and perforations 26 distributed around the opening 28 intended to form elastic deformation means according to, for example, for example, the embodiments explained above. As can be seen in FIG. 9, the opening 28 has a section βι and the perforations 26 comprise in particular holes of section e ₂ -

Such a step can be carried out by etching in dry or wet form, such as, for example, a deep reactive ion etching (also known by the abbreviation "DRIE").

In addition, in a second step, the method consists in forming the axially extending member, a pivot axis 27 in the example of FIGS. 9 to 11, in a second material with a main section e3 and a flared portion. radially 24 intended to be deformed with a maximum section e ₄ . The portion 24 may comprise a thickness of between 100 and 300 μιη. As explained above, the second step can be performed according to the usual processes for producing axes. The organ

27 is preferably metallic and may, for example, be formed of steel.

Of course, the first two steps have no consecutivity to respect and can even be performed at the same time.

In a third step, the flared portion 24 is introduced without contact into the opening 28. This means, as can be seen in FIG. 10, that the section βι of the opening 28 is greater than or equal to the external section e ₄ of the part flared 24 of the organ 27.

Preferably, the difference between the section βι of the opening

28 and the outer section e ₄ of the flared portion 24 is about 10 μιη, that is to say a gap of about 5 μιη which separates the body 25 from the part 3 with respect to the flared portion 24 of the organ 27. In addition, preferably according to the invention, the flared portion 24 and, incidentally, the member 27, is held in the opening 28 with a 21 of the tools 20, 21 used for the deformation step. Finally, preferably, the tool 21 comprises a recess 29 intended to receive a part of the member 27.

Finally, the method comprises a fourth step of elastically and plastically deforming the flared portion 24 of the member 27 by bringing the tools 20, 21 in the axial direction A in order to exert a uniform radial stress B against the wall of the part 3 surrounding the opening 28 by biasing the means of elastic deformation of the part 3, that is to say the cut-outs 26.

Thus, as can be seen in FIG. 11, the pressing of the flared portion 24 deformed at its upper and lower portions respectively by the tool 20 and 21 in the axial direction A will induce elastic and plastic deformation of the flared portion 24 exclusively in the direction B, that is to say towards the body 25.

In a preferred manner according to the invention, the deformation is parameterized so that the tightening is greater than the gap between the undeformed flared portion 24 and the wall of the body 25 surrounding the opening 28. Preferably, the tightening is between 8 and 20 μιη.

Therefore, it is desired that the elastic and plastic deformation of the flared portion 24 exerts the elastic deformation of the body 25 around the opening 28 in order to secure together the member 27 and therefore its flared portion 24 deformed, with the body 25 of the wheel 3 as shown in Figure 1 1. It should be noted that this embodiment allows in particular an automatic centering of the entire body 27 - body 25. As such, in Figure 1 1, we note that the perforations 26 have a section referenced e ₅ and no longer e ₂ .

Advantageously according to the invention, it is possible to secure the member 27 of any side of the body 25 of the wheel 3. In addition, no axial force (by definition potentially destructive) is applied to the body 25 of the wheel 3 during the process. Only a radial elastic deformation is applied to the body 25. It should also be noted that, preferably, the use of the radially flared portion 24 allows, during the radial deformation B of the flared portion 24, to exert a uniform stress on a maximized surface of the wall of the body 25 around the opening 28 to prevent any breakage of the wheel 3 of fragile material and adapt to the manufacturing dispersions of the various elements.

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 perforations of the piece of fragile material may comprise more or less series of holes than the embodiments presented above. In addition, the presented embodiments are capable of being combined with one another according to the intended applications.

The radially flared portion 24 may also comprise a different geometry in order to optimize or "program" the deformation towards the body 25. It may be, for example, considered to minimize or increase locally the thickness of the flared portion 24 in order to to favor one direction of deformation with respect to the other in the direction B. By way of example, it is thus conceivable to make a conical and coaxial recess with respect to the member 27 in order to facilitate the radial orientation B but also to render progressive induced stress.

Figures 1 and 2 show applications for an exhaust system such as the anchor 1 and the escape wheel 3 or a spiral 61 of a watch movement. Of course, the present assembly 2, 12, 22, 62 can be applied to other elements. One can, in a non-exhaustive way, consider forming a pendulum, a bridge or more generally a mobile with an assembly 2, 12, 22, 62 as explained above. It is also possible to use the assembly 2, 12, 22, 62 in place of the elastic deformation means 48 or the cylinders 63, 66 of the document WO 2009/1 15463 in order to fix a resonator of the balance-spring-monobloc type on a pivot axis.

Of course, two parts as described above can also be secured on the same axis with two separate assemblies 2, 12, 22, 62 to secure their respective movement. It is then understood that the same axis will be formed with two radially flared portions 4, 14, 24, 64 intended to be deformed.

Finally, the assembly 2, 12, 22, 62 according to the invention can also allow the joining of any type of watchmaking member or not whose body is formed of a material having no plastic field (silicon, quartz, etc.) with an axis such as, for example, a resonator of the tuning fork type or more generally a MEMS (acronym derived from the English term "Micro-Electro-Mechanical System").

Claims

1. Assembling (2, 12, 22, 62) a member (7, 17, 27, 67) extending axially in a first material in the opening (8, 18, 28, 68) of a workpiece (1 , 3, 61) in a second material having no plastic domain, characterized in that the piece (1, 3, 61) comprises cut-outs (6, 16, 26, 26 ', 26 ", 26"', 46, 46 ', 66) forming elastic deformation means distributed around its opening (8, 18, 28, 68) and in that said member (7, 17, 27, 67) comprises a radially flared portion (4, 14, 24, 64) and elastically and plastically deformed which radially clamps (B) the wall of said part surrounding the opening (8, 18, 28, 68) by biasing said elastic deformation means to secure the assembly (2, 12, 22, 62) non-destructively for said workpiece.

2. Assembly (2, 12, 22, 62) according to the preceding claim, characterized in that the outer wall of the portion (4, 14, 24, 64) deformed is substantially of corresponding shape to the opening (8, 18 , 28, 68) of the workpiece (1, 3, 61) to exert a substantially uniform radial stress (B) on the wall of the workpiece (1, 3, 61) surrounding said opening.

3. Assembly (2, 12, 22, 62) according to claim 1 or 2, characterized in that the opening (8, 18, 28, 68) of the part (1, 3, 61) is circular.

4. Assembly (2, 12, 22, 62) according to claim 1 or 2, characterized in that the opening (8, 18, 28, 68) of the part (1, 3, 61) is asymmetrical in order to avoid relative displacements between the elements of said assembly.

5. Assembly (2, 12, 22, 62) according to one of the preceding claims, characterized in that the perforations (6, 16, 26, 26 ', 26 ", 26"', 66) are formed remotely and around the opening (8, 18, 28, 68) by two series of diamond-shaped holes (31, 33) distributed in staggered rows to form beams (32) distributed in intersecting Vs.

6. Assembly (2, 12, 22, 62) according to the preceding claim, characterized in that the perforations (26 ', 26 ", 26"') comprise, between the first two series (31, 33) and the opening (8, 18, 28, 68), a third series which is formed of holes (35) in the form of a triangle and distributed in staggered with one (33) of the first two series to form beams (34) distributed in X secants.

7. Assembly (2, 12, 22, 62) according to the preceding claim, characterized in that the part (1, 3, 61) has slots (36) for communicating the third series of holes (35) with the opening (8, 18, 28, 68).

8. Assembly (2, 12, 22, 62) according to one of claims 1 to 4, characterized in that the perforations (46, 46 ') are formed at a distance and around the opening (8, 18, 28 , 68) by a first series of oblong holes (51) distributed in staggered rows with a second series of triangular holes (53), the second series (53) being closest to the opening (8, 18, 28, 68), each hole (53) of triangular shape communicating with the opening (8, 18, 28) by a notch (57) to form beams (52) movable radially according to the thickness of the oblong holes (51).

9. Assembly (2, 12, 22, 62) according to the preceding claim, characterized in that the perforations (46 ') comprise a third series of holes (55) in the form of a triangle, each hole (55) of the third series. being distributed between two holes (53) of triangular shape of the second series and communicating with the opening (8, 18, 28, 68) by a slot (56) to form beams (54) with two independent arms radially movable according to the thickness of the oblong holes (51) and tangentially according to the thickness of the slots (56).

10. Assembly (2, 12, 22, 62) according to one of the preceding claims, characterized in that the series of holes (31, 33, 35, 51, 53, 55) extend over a width of between 100 μιη and 500 μιη from the wall of the room (1, 3, 61) surrounding the opening (8, 18, 28, 68).

1 1. Assembly (2, 12, 22, 62) according to one of the preceding claims, characterized in that the opening (8, 18, 28, 68) has a section of between 0.5 and 2 mm.

12. Timepiece characterized in that it comprises at least one assembly (2, 12, 22, 62) according to one of the preceding claims.

13. A method of assembling a member (7, 17, 27, 67) extending axially in a first material in a part (1, 3, 61) in a second material not comprising a plastic field, said method comprising the following steps:

a) forming the part (1, 3, 61) with an opening (8, 18, 28, 68) and cut-outs (6, 16, 26, 26 ', 26 ", 26"', 46, 46 ', 66 ) distributed around the opening (8, 18, 28, 68) for forming elastic deformation means;

b) introducing without constraint, into the opening (8, 18, 28, 68), a portion (4, 14, 24, 64) flared radially of said member;

c) elastically and plastically deforming the flared portion (4, 14, 24, 64) of said member in the opening by axial approximation of two tools (20, 21) respectively at the upper and lower portions of said flared portion so as to exert a radial stress (B) against the wall of the part (1, 3, 61) surrounding the opening

(8, 18, 28, 68) by biasing said elastic deformation means of the workpiece (1, 3, 61) to allow the assembly (2, 12, 22, 62) to be non-destructively secured to said workpiece.

14. Method according to the preceding claim, characterized in that the outer wall of the flared portion (4, 14, 24, 64) of said member in the opening is substantially of corresponding shape to the opening (8, 18, 28, 68) of the workpiece (1, 3, 61) in order to exert a substantially uniform radial stress (B) on the wall of the workpiece (1, 3, 61) surrounding the opening (4, 14, 24, 64).

15. The method of claim 13 or 14, characterized in that the opening (8, 18, 28, 68) of the part (1, 3, 61) is circular.

16. The method of claim 13 or 14, characterized in that the opening (8, 18, 28, 68) of the part (1, 3, 61) is asymmetrical in order to avoid relative displacements between the elements of said assembly. .

17. The method of assembly according to one of claims 13 to 16, characterized in that, in step b), the difference between the section (ei) of the circular opening (8, 18, 28, 68 ) and the outer section (e ₄ ) of the flared portion (4, 14, 24, 64) of said member in the opening is about 10 μιη.

18. The assembly method according to one of claims 13 to 17, characterized in that, in step c), the deformation exerts a clamping between 8 and 20 μιη.

19. The method of assembly according to one of claims 13 to 18, characterized in that, during steps b) and c), the flared portion (4, 14, 24, 64) of the member (7, 17 , 27, 67) in the opening is held in the opening (8, 18, 28, 68) by one of the two tools (20, 21).

20. The assembly method according to one of claims 13 to 19, characterized in that the second material is formed based on silicon.

21. Assembly method according to one of claims 13 to 20, characterized in that the first material is formed based on metal or metal alloy.

22. The assembly method according to one of claims 13 to 21, characterized in that the piece is a mobile (3) clock.

23. Assembly method according to one of claims 13 to 21, characterized in that the piece is an anchor (1) clock.

24. The assembly method according to one of claims 13 to 21, characterized in that the piece is a spiral (61) clock.

25. The assembly method according to one of claims 13 to 21, characterized in that the piece is a resonator.

26. The assembly method according to one of claims 13 to 21, characterized in that the piece is a MEMS.