Patent ID: 12189338

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS.1to4show an embodiment of the elastic holding member1for fixing a timepiece component2on a support element3a,3b. By way of example, the elastic holding member1can be a collet for fixing the timepiece component2such as a spiral to a support element3a,3bsuch as a “stub axle”3aand a balance shaft3bvisible respectively inFIGS.1and2. This stub axle3aalso called adjustment axle, stub shaft or classification axle is specifically used in the context of adjustment of a balance-spring assembly according to different known techniques such as the technique called omega-metric technique consisting in carrying out a classification of the spirals, a classification of the balances, a pairing of a balance selected in a particular class, with a spiral also selected in a particular class, these classes being compatible with each other.

It should be noted that with regard to the balance shaft3b, it can also be called by its synonym the balance axle and is in particular designed to receive the collet.

This elastic holding member1is made of a material called “fragile” material, preferably a micromachinable material. Such material may comprise silicon, quartz, corundum, silicon and silicon dioxide, DLC, metallic glass, ceramic, other at least partially amorphous material, or the like.

In this embodiment, this holding member1can be comprised in an elastic holding member-timepiece component assembly120visible inFIGS.5and6. Such an assembly120is intended to be arranged in a horological movement110of a timepiece100visible inFIG.6, and also to be driven on a support element3asuch as the balance shaft or to be placed on a support element3bsuch as the stub axle when carrying out a classification operation. Such an assembly120can be made in one piece and be made of a “fragile” material similar to that of the collet.

It will be noted that in a variant of this assembly120, only the elastic holding member1can be made of such a material called “fragile” material, the timepiece component2then being made of another material.

This assembly120can form part of an assemblage130a,130bfor the horological movement110or else for a device140for performing a classification operation, by being mounted on the support element3a,3b, here the balance shaft or the stub axle. Such a device140visible inFIG.5, comprises in particular a measuring module150and the support element3ahere the stub axle3a. It will be noted that this assemblage130a,130bwas designed for applications in the watchmaking field. However, the invention can perfectly be implemented in other fields such as aeronautics, jewelry, or else automotive.

Such a holding member1comprises outer and inner structures4a,4bas well as an upper face and a lower face12which are preferably flat, both of which are respectively comprised in first and second planes P1and P2. These outer and inner structures4a,4bcalled hereinafter outer and inner peripheral walls4a,4brespectively delimits the outer and inner contours of this holding member1, the inner contour defining an opening5of this holding member. The outer and inner peripheral walls4a,4bdefine different shapes of the holding member1. This holding member1has a thickness which extends from the upper face to the lower face12. As mentioned above, this holding member1may correspond to any type of collet, comprising arms6each including an elastic sub-arm or rigid and elastic sub-arms7a,7b. These arms6are hereinafter called “structural elements6” of this holding member1. Such structural elements6together form the body of this holding member1. Indeed, each structural element6comprises a portion of the outer and inner peripheral walls4a,4bas well as a portion of the upper and lower faces12. These structural elements6are preferably solid. In other words, these structural elements6are preferably not hollow. Under these conditions, the rigid sub-arms7aand the elastic sub-arms7bare hereinafter called respectively first structural sub-elements7aand second structural sub-elements7b.

The outer peripheral wall4aof such a holding member1may have any shape, for example being essentially triangular, circular or even a shape similar to that of a quadrilateral. As previously mentioned, the inner peripheral wall4bof this holding member1participates in defining the opening5of this holding member1into which the support element3a,3bis intended to be inserted. This opening5defines a volume in the holding member1which is smaller than that of a connecting part of one end of the support element3a,3bwhich is intended to be arranged therein. It will be noted that this connecting part comprises all or part of the portions10defined on the peripheral wall21of the support element3a,3band which are intended in particular to cooperate with specific and/or dedicated first and second holding parts20a,20bof the structural elements6. These first and second holding parts20a,20bare each intended to ensure mounting of said holding member1on different support elements3a,3bhere a balance shaft and a stub axle. As will be seen below, these first and second holding parts20a,20beach comprise at least one contact area8a,8bconfigured to cooperate with the corresponding support element3a,3b. Each contact area8a,8bof the first and second holding parts20a,20bis able to cooperate with a corresponding contact portion10of the corresponding support element3a,3bby being preferably in a contact configuration of the plano-convex type.

As regards the outer peripheral wall4a, it is in particular intended to be connected to the timepiece component2by means of at least one attachment point11arranged in the outer peripheral wall of the holding member1.

For a better understanding, the invention will be described below for a holding member1such as a collet illustrated inFIGS.1to4, comprising structural elements6each including a first structural sub-element7aand a second structural sub-element7b. This holding member1comprises an inner surface4bhaving a generally hexagonal shape comprising parts having convex shapes. Each of these parts is comprised in a connection area9connecting a second structural sub-element7bto a first structural sub-element7a. The inner peripheral wall4bof this holding member1has a non-triangular shape. It will be noted that the connecting part comprises all or part of the portions10defined on the peripheral wall21of the support element3a,3band which are intended in particular to cooperate with specific and/or dedicated first and second holding parts20a,20bof the first structural sub-elements7a.

This holding member1therefore comprises the first structural sub-elements7aand second structural sub-elements7bconnecting the outer and inner peripheral walls4a,4bto one another. It will be noted that this holding member1comprises as many first structural sub-elements7aas there are second structural sub-elements7b. The first structural sub-elements7aare here undeformable or almost undeformable and play a role of stiffening elements of the holding member1. As regards the second structural sub-elements7b, they have elasticity properties in particular in comparison of the first structural sub-elements7a. Indeed, these second sub-elements7bare able to deform mainly in tension but also in torsion. These first structural sub-elements7aand these second structural sub-elements7bare defined or even distributed successively and alternately in this holding member1. In other words, these first structural sub-elements7aare interconnected by said second structural sub-elements7b. More specifically, each second structural sub-element7bis connected at its two opposite ends at connection areas9to two different first structural sub-elements7a. As already mentioned previously, such first and second structural sub-elements7a,7bcomprise in a non-limiting and non-exhaustive manner:inner faces comprised in the inner peripheral wall4band which also participate in defining the opening5of this holding member1, andouter faces comprised in the outer peripheral wall4aof this holding member1.

It will be noted that the inner faces of the second structural sub-elements7bare essentially flat and the inner faces of the first structural sub-elements7amay be non-flat, for example being corrugated. In this context, the inner face of each first structural sub-element7acomprises a connecting portion19provided with first and second holding parts20a,20bvisible inFIG.4and which are intended for mounting said holding member1respectively on support elements3a,3beach having a different cross section. Note that this connecting portion19is also called “mounting portion19” or else “assemblage portion19”.

These first and second holding parts20a,20bwhich can also be called “mounting parts” or “assemblage parts” or else “connecting parts”, are comprised in a connecting portion19of each first structural sub-element7a, said portion19being included in the inner face of the holding member1extending over all or part of the thickness of this holding member1. In other words, each first and second retaining part20a,20btherefore extends over all or part of the thickness of the holding member1.

The first and second holding parts20a,20beach comprise at least one area8a,8bof contact with the corresponding support element3a,3b. Each contact area8a,8bcan be rounded or convex or else flat. The contact area8a,8bof each first and second holding parts20a,20b, is able to cooperate with the peripheral wall21of a connecting part of the support element3a,3bin particular with a corresponding contact portion10defined in this peripheral wall21, by being in a contact configuration of the plano-convex type.

These first structural sub-elements and these second structural sub-elements7a,7bconnect the outer and inner peripheral walls4a,4bof the holding member1to each other. In this holding member1, these first and second structural and elastic sub-elements7a,7bessentially allow to achieve a coupling of the elastic clamping type of the support element3a,3bin the opening5made in this holding member1which is defined by the inner peripheral wall4bof this holding member1.

As already seen, these first structural sub-elements7atherefore comprise only the contact areas8a,8bof the holding member1with the support element3a,3bwhich can be defined in all or part of the connecting portion19of each first structural sub-element7a.

In this context, the first holding part20acomprises at least one contact area8a. This first holding part20ais intended to cooperate with the peripheral wall21of the support element3a, for example here the stub axle3a. Such a support element3ahas a cross section different from that of another support element3bsuch as the shaft3b, the peripheral wall of which is intended to cooperate only with the second holding part20bof each first structural sub-element7aof the holding member1. The difference(s) of this cross section may relate to the shape of this section, in particular its geometric shape, but not exclusively.

It will be noted that, the shape and/or the dimensions of this section are specifically defined so that said at least one contact area8ais the only contact area8aof the connecting portion19of each first structural sub-element7awhich is configured to cooperate exclusively with the peripheral wall21of this support element3a.

Indeed, in the present embodiment and with reference toFIG.1, the section of this support element3ais non-circular, preferably mainly triangular, being formed of three essentially flat faces. In this context, the flat faces of this support element3acomprise the contact portions10of this element3a, portions10which are therefore also flat. With reference toFIG.4, the connecting portion19of each first structural sub-element7acomprises a substantially hollow or substantially concave part and two contact areas8adefined at its ends and extending substantially over all or part of the thickness of the holding member1. These two contact areas8aare specifically defined so as to cooperate with the corresponding contact portions10comprised in the peripheral wall21of this support element3a. Such contact areas8aeach have a preferably convex surface and delimit the ends of the connecting portion19of each first structural sub-element7a. The convex surface of each of these contact areas8athus enables them to achieve with the contact portions10a contact configuration of the plano-convex type. It should be noted here that the flat face of each contact portion10of the support element3ais assessed relative to the convex surface of each corresponding contact area8aagainst which this portion10is arranged. In this configuration, the presence of two convex contact areas8ain the connecting portion19of each first structural sub-element7aallows to produce a contact pressure between the holding member1and the support element3awhen making a mechanical connection between them, while consequently reducing the intensity of the stresses at these contact areas8aand the corresponding contact portions10aof the support element3awhen assembling and/or fixing this holding member1with the support element3ahere the stub axle, which stresses are liable to damage the holding member1by the appearance of breaks/fractures or else cracks. In other words, as there is no driving of the support element3a, which in this embodiment has an increasing triangular section defining a cone in the axial direction of this element3aand that the connecting member1is simply blocked on the maximum section of this cone, the stresses are then almost zero or even zero.

Regarding the second holding part20b, it also comprises at least one contact area8b. This second holding part20bis intended to cooperate with the peripheral wall21of a support element3bsuch as the balance shaft3b. Such a support element3bhas a cross section different from that of another support element3asuch as the stub axle3a, the peripheral wall of which is intended to cooperate only with the first holding part20aof each first structural sub-element7aof the holding member1. The difference(s) of this cross section may relate to the shape of this section but not exclusively.

It will be noted that, the shape and/or the dimensions of this section are specifically defined so that said at least one contact area8bis the only contact area8bof the connecting portion19of each first structural sub-element7awhich is configured to cooperate exclusively with the peripheral wall21of this support element3b.

Indeed, in the present embodiment, with reference toFIG.2, the section of this support element3bis preferably circular. InFIG.4, the connecting portion19of each first structural sub-element7acomprises a substantially hollow or substantially concave part wherein two contact areas8bare comprised. These two contact areas8bare able to cooperate with the corresponding contact portions10of the support element3b. Such contact areas8bare defined in the connecting portion19, in particular in the concave part of this connecting portion19, extending substantially over all or part of the thickness of the holding member1. In addition, these contact areas8bare flat, each comprising a surface which is entirely or partly flat. In the connecting portion19, the two contact areas8bof each first structural sub-element7aotherwise called flat contact areas8b, are respectively comprised in different planes together forming an obtuse angle. These two contact areas8bof each first structural sub-element7aare separate by being spaced from each other. In other words, the connecting portion19comprises a separation area18of the two contact areas8bof each first structural sub-element7avisible inFIG.4.

The contact areas8bof the first structural sub-elements7aare provided in particular to cooperate with the contact portions10according to a contact configuration of the plano-convex type in which configuration where the flat surface of each contact area8bcooperates with the corresponding contact portion10of convex shape of the support element3. It should be noted here that this convex shape of each contact portion10is assessed relative to the flat surface of each corresponding contact area8bopposite which this portion10is arranged. It will be noted that this flat surface of each contact area8bforms a plane tangent to the diameter of the support element. In other words, the flat surface is perpendicular to the diameter and therefore to the radius R1of the support element.

In this configuration, the presence of two flat contact areas8bin the connecting portion19of each first structural sub-element7aallows to apply a contact pressure between the holding member1and the support element3bwhen making a mechanical connection therebetween, while consequently reducing the intensity of the stresses at these contact areas8band the corresponding contact portions10of the support element3bwhen assembling and/or fixing this holding member1with the support element3b, which stresses are liable to damage the holding member1by the appearance of breaks/fractures or else cracks.

It will be noted that these two flat contact areas8bare preferably distributed separately over the connecting portion19of each first structural sub-element7a, between the two contact areas8aof the first holding part20a.

In a variant, the second holding part20bcomprises a single flat contact area8bcomprised on the connecting portion19of each first structural sub-element7a, equidistantly from the two contact areas8aof the first holding part20a.

The holding member1then comprises twelve contact areas8a,8b, six of which referenced8aare configured to cooperate exclusively with a support element3a, for example of the stub axle3atype in the context of classification operations, and six others with a support element3b, for example of the balance shaft type, to achieve precise centring of the timepiece component2, for example a spiral, in the horological movement110. In this holding member1, each first structural sub-element7ahas a volume or amount of material which is substantially greater or strictly greater than the volume or amount of material constituting each second structural sub-element7b. It will indeed be noted that the outer and inner peripheral walls4a,4bare separated from one another in this holding member1by a variable distance E which then changes depending on whether these peripheral walls4a,4bare comprised, for example, in a first structural sub-element7aor else a second structural sub-element7b. Indeed, this distance E is a maximum distance E1when it is defined between parts of the inner and outer peripheral walls comprised in each first structural sub-element7a, that is to say the maximum distance E1present between the inner and outer faces of this first structural sub-element7a. In particular, for each first structural sub-element7a, this maximum distance E1is defined between a part of the outer peripheral wall of this first structural sub-element7aand each contact area8adedicated to cooperating with the peripheral wall21of the support element3bsuch as the stub axle, this contact area8abeing comprised in the inner face of the inner peripheral wall of this first structural sub-element7a. It will also be noted that this maximum distance E1is greater than a distance E3defined between a part of the outer peripheral wall of the first structural sub-element7aand each contact area8bdedicated to cooperating with the peripheral wall21of the support element3bsuch as the balance shaft3b, this contact area8bbeing comprised in the inner face of the inner peripheral wall4bof this first structural sub-element7a.

Moreover, this distance E is a minimum distance E2when it is defined between parts of the outer and inner peripheral walls4a,4bcomprised in the second structural sub-elements7b, or the minimum distance E2present between the inner and outer faces of this second structural sub-element7b. Such a minimum distance E2is constant or substantially constant over the entire length over which these second structural sub-elements7bextend. This length is here parallel or substantially parallel to the outer and inner peripheral walls4a,4bcomprised in these second structural sub-elements7b. In addition, the distance E2is in this holding member1, less than the smallest distance defined in the first structural sub-element7a. In other words, the distance E2is the smallest distance that is defined between the outer and inner peripheral walls4a,4bof this holding member1.

It is therefore understood here that each second structural sub-element7bhas a cross section which is smaller than a cross section of each first structural sub-element7a. In other words, the cross section of each second structural sub-element7bhas an area which is less than an area of the cross section of each first structural sub-element7a. Note that the cross section of the second structural sub-element7bis constant or substantially constant throughout the body of this second structural sub-element7bwhile the cross section of the first structural sub-element7ais inconstant/variable throughout the body of this first structural sub-element7a. In addition, it will be noted that:the cross section of each first structural sub-element7ais preferably a solid or partially solid section which is perpendicular to the longitudinal direction wherein the body of this first structural sub-element7aextends, andthe cross section of each second structural sub-element7bis preferably a solid or partially solid section which is perpendicular to the longitudinal direction along which the body of this second structural sub-element7bextends.

Such a configuration of the first structural sub-elements and of the second structural sub-elements7a,7ballows the holding member1to store a greater amount of elastic energy for the same clamping compared with the holding members of the prior art. Such an amount of elastic energy stored in the holding member1then allows to obtain a greater holding torque of the holding member on the support element3a,3bin the assemblage130a,130bof the holding member-timepiece component assembly120with this support element3a,3b. In other words, such an excess of elastic energy stored in the holding member1therefore increases the holding torque and allows optimum elastic clamping. In addition, it should be noted that such a configuration of the holding member1allows to store elastic energy ratios which are 6 to 8 times greater than those of the holding members of the prior art.

It will be noted that the arrangement of the first structural sub-elements and these second structural sub-elements7a,7bin the holding member1allows, during an insertion with clamping, a deformation of each second structural sub-element7ballowing to accommodate the deformation of the assembly of the holding member1with the geometry of the connecting part of the support element3a,3bon which it is assembled. In addition, the mode of deformation that each second structural sub-element7bundergoes is a toroidal torsion coupled with a radial expansion.

With reference toFIG.7, the invention also relates to a method for producing the assemblage130a,130bof the elastic holding member-timepiece component assembly120with the support element3a,3bfor example the balance shaft3bor the stub axle3a. This method comprises a step13of mounting the support element3a,3bon the holding member1. During this step13, the support element3a,3bis inserted into the opening5of the holding member1more precisely the end of this support element3a,3bis presented at the entrance of this opening5defined by the inner peripheral wall4bof the holding member1in anticipation of the introduction of the connecting part of this support element3a,3bin the volume defined in this opening5.

When it comes to the assemblage130aof elastic holding member-timepiece component the assembly120with the support element3asuch as a stub axle3a, this step13comprises a fitting sub-step14aduring which the collet is placed on this stub axle3ain anticipation, for example, of performing the classification operation. This step13also comprises a sub-step16aof coupling this holding member1with the support element3ahere the stub axle3a. During this sub-step16a, the coupling is carried out without elastic clamping, thanks to the complementarity of their shape which thus allows cooperation between the latter when they are rotated when performing the classification operation. It will be noted that this complementarity of their shape results in particular from the fact that this holding member1and the support element3ahave different shapes. In addition, during this mounting step13only the contact areas referenced8acooperate with the portions10of the peripheral wall21of the connecting part of the support element3a.

When it comes to the assemblage130bof the elastic holding member-timepiece component assembly120with the support element3bsuch as a balance shaft3b, this step13comprises a sub-step of elastic deformation14bof the holding member1in particular of a central area of this holding member1, the contour of which comprises said opening5, which deformation resulting from the application of a contact force on the contact areas8bof the first structural sub-elements7aby the portions10of the peripheral wall21of the connecting part of the support element3b.

As previously mentioned, this elastic deformation of the holding member1results from the application of the contact force on the contact areas8bof the first structural sub-elements7aby the portions10of the peripheral wall21of the support element3b. Such a deformation sub-step14bcomprises a phase of displacement15of the first structural sub-elements7aunder the action of the contact force applied thereto. Such a displacement of the first structural sub-elements7ais carried out in a direction comprised between a radial direction B1relative to a central axis C which is common to the support element3band to the holding member1, and a direction B2combined with this central axis C. It will be noted that this direction B2is perpendicular to the direction B1and is oriented in a defined direction from the lower face12towards the upper face. The contact force is preferably perpendicular or substantially perpendicular to each contact area8b.

It will be noted that in the context of the embodiment of the holding member1described and illustrated inFIGS.1to4, during the progress of this phase15, the first structural sub-elements7athus displacing under the action of this contact force, generate a double elastic deformation of the second structural sub-elements7b.

A first deformation otherwise called “torsional elastic deformation” of these second structural sub-elements7b. During this torsional deformation, each second structural sub-element7bis driven at its two ends in the same direction of rotation B4by the first displacing structural sub-elements7ato which such ends are connected. It will be noted that only part of the body of these second structural sub-elements7bis torsionally deformable here the ends of these second structural sub-elements7b. Such a first deformation contributes in particular to then causing a torsional deformation of each structural element6. This first deformation allows to improve the insertion of the support element3binto the opening5of the holding member1while helping to prevent any breakage of the holding member1and/or any appearance of a crack in this member1during its assemblage with the support element3b.

A second deformation otherwise called “tension deformation” or else “elastic extension deformation” of the second structural sub-elements7b. During this extension deformation, each second structural sub-element7bis pulled at its two ends in the longitudinal direction B3in opposite directions by the first displacing structural sub-elements7ato which such ends are connected. Such a second deformation of the second structural sub-element7bcontributes in particular to the fact that each structural element6stores a large amount of elastic energy. In other words, the support element1also stores a large amount of elastic energy

This double elastic deformation of the second structural sub-elements7bcan be carried out simultaneously or substantially simultaneously, or alternatively successively or substantially successively. It will be noted in the context of the implementation of this phase15, when this double elastic deformation is carried out successively or substantially successively, the first deformation is then carried out before the second deformation.

This mounting step13then comprises a sub-step16bof fixing the holding member1on the support element3b. Such a fixing sub-step16bcomprises a phase17of performing a radial elastic clamping of the holding member1on the support element3b. It is therefore understood that in such a state of stress, the holding member1stores a large amount of elastic energy which contributes to giving it a substantial holding torque, in particular allowing optimum twisting by elastic clamping.