Patent Application
20240176297
The present invention pertains to an elastic fastening element for timepieces, more particularly an element for holding a timepiece component on a fixed or mobile support element, such as a staff, by elastic clamping of the support element.
Such elastic fastening elements are known in the prior art and may be for example in the form of a collet for fastening the inner end of a balance-spring to the staff of a balance, and a clamp for fastening the outer end of a balance-spring to a balance-spring stud.
These elastic fastening elements are very advantageous in that they make it possible to easily and height-adjustably mount the balance-spring on the balance staff and the balance-spring stud.
The present invention aims to further improve these elastic fastening elements by making them capable of exerting a greater clamping force and/or of further deforming.
The aim of the present invention is to overcome all or part of the aforementioned drawbacks by proposing an elastic fastening element that has a high holding torque particularly to facilitate/simplify the mounting operations of an assemblage of an elastic fastening element-timepiece component assembly with a support element as well as to ensure sufficient hold to guarantee that it is held in position in the plane and to guarantee its angular position during the life of the component.
To this end, the invention relates to an elastic fastening element for holding a timepiece component on a support element, comprising an opening the contour of which comprises at least four contact areas for receiving and clamping the support element in said opening, said contact areas each being included on an inner face of a deformable portion provided with a through-hole of the fastening element.
In other embodiments:
The invention also relates to an elastic fastening element-timepiece component assembly for a horological movement of a timepiece comprising such a fastening element.
Advantageously this assembly is made in one piece.
The invention also relates to an assemblage for a horological movement of a timepiece comprising such an elastic fastening element-timepiece component assembly, said assembly being fastened to a support element.
The invention also relates to a horological movement comprising at least one such assemblage.
The invention also relates to a timepiece comprising such a horological movement.
The invention also relates to a method for performing such an assemblage of an elastic fastening element-timepiece component assembly with a support element, comprising:
Other specific features and advantages will become clearly apparent from the description which is given below, by way of indicative and non-limiting example, with reference to the appended drawings, wherein:
In these embodiments, this fastening element 1a, 1b, 1c may be included in an elastic fastening element-timepiece component assembly 120 that can be seen in
In the context of the invention, this fastening element 1a, 1b, 1c has a thickness between 50 and 150 μm. Such a thickness is preferably in the order of 100 μm.
It will be noted that in a variant of this assembly 120, only the elastic fastening element 1a, 1b, 1c may be made of such a so-called “fragile” material, the timepiece component 2 then being manufactured in another material.
This assembly 120 may form part of an assemblage 130 for the horological movement 110, by being fastened to the support element 3 for example by elastic clamping. It will be noted that this assemblage 130 was designed for applications in the watchmaking field. However, the invention may be implemented perfectly in other fields such as aeronautics, jewellery, or also automotive.
Such a fastening element 1a, 1b, 1c comprises an opening 5 also called “central opening” wherein the support element 3 is intended to be inserted. This opening 5 defines a volume in the fastening element 1a, 1b, 1c that is smaller than that of a connecting portion of an end of the support element 3 that is provided to be arranged therein. It will be noted that this connecting portion has a circular cross section and comprises all or part of the contact portions defined on a peripheral wall of the support element 3.
Such an element 1a, 1b, 1c also comprises an upper face and a lower face 12 preferably flat respectively included in first and second planes P1 and P2 that can be seen in
This element 1a, 1b, 1c also comprises inner and outer peripheral walls 9a, 9b that connect the upper and lower faces 12 to one another. The outer peripheral wall 9b comprises a surface that externally delimits the contour of the fastening element 1a, 1b, 1c. This peripheral wall 9b gives this element 1a, 1b, 1c an essentially polygonal shape of the type octagonal in
This fastening element 1a, 1b, 1c comprises a body provided with at least four deformable portions 7 also called “flexible portions” or also “elastic portions”. Each deformable portion 7 is configured to return to its original shape after having been deformed. In other words, these portions are reversibly deformable portions 6. The body of this element 1a, 1b, 1c is rigid or essentially rigid, with the exception of the deformable portions 7 that it includes. In other words, this body comprises deformable portions 7 and rigid portions 6. Rigid portions 6 means portions 6 that withstand pressure or deformation, namely non-deformable portions. In the elastic fastening element 1a, 1b, 1c, the rigid portions 6 are configured to be essentially subjected to tensile stress. In this configuration, these rigid portions 6 withstand pressure or tensile deformation.
It is therefore understood that in the body of this element 1, the deformable portions 7 are separated from one another by the rigid portions 6. It can also be said that these deformable portions 7 are connected to one another by these rigid portions 6. It will be noted that each deformable portion 7 is arranged in the body of said element 1a, 1b, 1c at equal distance from each of the other deformable portions 7 that are arranged in its direct vicinity, or closest vicinity, in said body.
In this configuration, each deformable portion 7 extends between the inner and outer peripheral walls 9a, 9b of the body of the element 1a, 1b, 1c. It will be noted that such deformable portions 7 are similar to one another. In this element 1, these portions 7 form an excrescence in the inner peripheral wall 9a of the body of the element 1a, 1b, 1c that extends in the direction of the centre O of the fastening element 1a, 1b, 1c.
Each deformable portion 7 comprises a receiving region 8a, two connection regions 8b and an outer region 8c. These regions 8a, 8b, 8c together delimit the periphery of a through-hole 6 of this portion 7.
In this configuration, the receiving region 18a is included between the inner peripheral wall 9a of the element 1a, 1b, 1c and a portion of the periphery of the through-hole 4 by being connected to the two connection regions 8b of this deformable portion 7. This receiving region 8a is provided with an inner face 14 comprising the contact area 13 of each deformable portion 7. This inner face 14 is formed by a portion of the inner peripheral wall 9a that is included in this portion 7. In other words, this inner face 8 is included at the end of the excrescence forming this deformable portion 7 facing the centre O of the fastening element 1. In this configuration, the contact area 13 may have:
This contact area 13 comprises a substantially hollow or substantially concave portion wherein two bearing areas are included. These two bearing areas are able to cooperate with the corresponding convex contact portion of the support element 3. Such bearing areas are defined/included in the surface of this contact area 13 by extending substantially over all or part of the thickness of the attachment part 1. In addition, these bearing areas are flat by each comprising a surface that is entirely or partly flat. In the contact area 13, the two bearing areas are respectively included in different planes together forming an obtuse angle. These two bearing areas are disjoint by being spaced apart from one another. In other words, the contact area 13 comprises an area for connecting the two bearing areas. This connection area preferably has a rounded shape.
These bearing areas are provided particularly to cooperate with the contact portions according to a contact configuration of piano-convex or also piano-cylindrical type if the cylindrical shape of the support element 3 is taken into account. In this configuration, the flat surface of each bearing area cooperates with the corresponding contact portion of convex shape of the support element 3. Here, it is specified that this convex shape of each contact portion is assessed relative to the flat surface of each corresponding bearing area opposite to which this portion is arranged. It will be noted that this flat surface of each bearing area forms a plane tangent to the diameter of the support element 3. In other words, the flat surface is perpendicular to the diameter and therefore to the radius of the support element.
In this configuration, the presence of two flat bearing areas in each contact area 13 of the attachment part 1 makes it possible to carry out a contact pressure between this attachment part 1 and the support element 3 during the production of a mechanical connection between them and this, while substantially reducing the intensity of the stresses at these bearing areas and the corresponding contact portions of the support element 3 during the assemblage and/or fastening of this attachment part 1 with the support element 3, which stresses being likely to damage the attachment part 1 by the appearance of fractures/breaks or also cracks.
In this element 1, the presence of this contact area 13 in the inner face 8 of each deformable portion 7 makes it possible to carry out a contact pressure between this element 1a, 1b, 1c and the support element 3 during the production of a mechanical connection between them and this, while substantially reducing the intensity of the stresses at this contact area 13 and the corresponding contact region of the support element 3 during the assemblage and/or fastening of this element 1a, 1b, 1c with the support element 3, which stresses being likely to damage said element 1a, 1b, 1c by the appearance of fractures/breaks or also cracks.
As we have already seen, these deformable portions 7 therefore comprise the only contact areas 13 of the element 1a, 1b, 1c with the support element 3 that may be defined in all or part of the inner faces 8 of these portions 7. With reference to
In each deformable portion 7, the outer region 8c is included between the outer peripheral wall 9b of the element 1a, 1b, 1c and a portion of the periphery of the through-hole 4 by also being connected to two connection regions 8b. As regards these two connection regions 8b, they are each included between an end of a rigid portion 6, a portion of the outer peripheral wall 9b and a portion of the periphery of the through-hole. It will be noted that these two connection regions also connect the receiving 8a and outer 8c regions to one another.
In the element 1, the deformable portion 7 comprises the through-hole 4, also called recess, and which is defined in the thickness of this element 1a, 1b, 1c. This through-hole 4 opens both onto the upper and lower faces 10 of the element 1a, 1b, 1c. It can also be said that this through-hole 4 opens onto an end in the upper face of the deformable portion 7 and onto another end in the lower face 10 of this portion 7. This hole 4 extends in a direction of the axis of revolution A and this, from the upper face to the lower face 10 or vice versa. In other words, this hole 4 connects these two faces 10 to one another. This through-hole 4 defines a void volume or also a void volume of material or of no material. It is therefore understood that this volume corresponds to a variable or configurable volume. This volume comprises an open enclosure delimited by a peripheral wall of this hole 4. Such a through-hole 4 represents approximately between 20 and 80 percent of the body of the deformable portion 7. Preferably, this through-hole 4 represents 30 percent of this body.
In these conditions, it will be noted that each deformable portion 7 is configured to modify the volume defined by this through-hole 4 when this portion 7 is placed under constraint by the support element 3.
In this element 1a, 1b, 1c, the rigid portions 6 extend between the inner and outer peripheral walls 9a, 9b of the body of the element 1a, 1b, 1c. These rigid portions 6 preferably have an elongated shape. Indeed, each rigid portion extends longitudinally between two deformable portions 7 to which it is connected. It is therefore understood that each rigid portion 6 is directly connected at each of its two ends opposite two deformable portions 7. Additionally, it will be noted that the deformable 7 and rigid portions 6 are arranged successively and alternating in the fastening element 1a, 1b, 1c. Each rigid portion 6 is connected to two different deformable portions 7, which deformable portions 7 are “directly” connected to the other rigid portions 6 of the element 1a, 1b, 1c. It will be noted that the rigid portions 6 here are non-deformable or almost non-deformable and act as elements for stiffening the fastening element 1a, 1b, 1c.
Moreover, in each deformable portion 7, the receiving region 8a, the two connection regions 8b and the outer region 8c mark/surround/delimit the through-hole 4. More precisely, these regions 8a to 8c are configured to be deformed in different ways as soon as they are constrained by the insertion of the support element 3 into the opening 5 of the element 1a, 1b, 1c. Indeed, for each deformable portion 7 each of these regions 8a to 8c has a deformation coefficient Crr, Crl, Cre the value of which reduces, as this region 8a, 8b, 8c is moved away from the contact area 13 of the receiving region 8a. In other words, the deformation coefficient Crr, also called average deformation coefficient Crr of the receiving region 8a has a high value or higher than the value of the coefficient Crl of two connection regions 8b and of that of the coefficient Cre of the outer region 8c. In addition, the coefficients Crl of the two connection regions 8b have similar or substantially similar values that are higher than that of the coefficient Cre of the outer region 8c. In other words, the relation between these average deformation coefficients Crr, Crl, and Cre of these regions 8a, 8b, 8c may be defined according to the following mathematical formula:
Crr>Crl>Cre
It will be noted that the deformations of these regions 8a, 8b, 8c generate a radial displacement relative to the axis of revolution A, of each one of them. The significance/intensity of these radial displacements are of course a function of the average deformation coefficients Crr, Crl, Cre of these regions 8a, 8b, 8c.
In this fastening element 1, these rigid and deformable portions 6, 7 essentially make it possible to perform a fastening of the elastic clamping type of the support element 3 in the opening 5 made in this fastening element 1a, 1b, 1c which is defined by the inner peripheral wall 9a of this fastening element 1a, 1b, 1c.
As we have already seen, these deformable portions 7 comprise the only contact areas 13 of the fastening element 1a, 1b, 1c with the support element 3 that may be defined in all or part of the inner faces 14 of these deformable portions 7. The contact area 13 of each deformable portion 7 is provided to cooperate with a peripheral wall 10 of the connecting portion of the support element 3 in particular with the corresponding contact region defined in this peripheral wall 10 of the support element 3. In this context, the fastening element 1a, 1b, 1c then comprises at least four contact areas 13 that participate in performing an accurate centring of the timepiece component 2, for example a balance-spring, in the horological movement 110.
In this configuration, the elasticity or the flexibility of the element 1, is defined relative to the contact areas 13 of this element 1a, 1b, 1c more specifically relative to the intensity of the deformation of the deformable portions 7 during the application of a force on these contact areas 13.
Moreover, in this fastening element 1a, 1b, 1c, the rigid 6 and deformable portions 7 make it possible for the fastening element 1a, 1b, 1c to store a larger amount of elastic energy for the same clamping in comparison with the fastening elements of the prior art. It will be noted that this large storage of energy is particularly related to the volume of material constituting this fastening element 1a, 1b, 1c provided with through-holes 4 and rigid portions 6 subjected to tensile stress. Such an amount of elastic energy stored in the fastening element 1a, 1b, 1c then makes it possible to obtain a higher holding torque of the fastening element on the support element 3 in the assemblage 130 of the fastening element-timepiece component assembly 120 with this support element 3. Additionally, it will be noted that such a configuration of the fastening element 1a, 1b, 1c makes it possible to store elastic energy ratios that are 6 to 8 times greater than those of the fastening elements of the prior art.
It will be noted that the arrangement of the rigid and deformable portions 6, 7 in the fastening element 1a, 1b, 1c makes it possible, during an insertion with clamping, to deform each deformable portion 7 making it possible to accommodate the deformation of the whole fastening element 1a, 1b, 1c with the geometry of the connecting portion of the support element 3 on which it is assembled.
In addition, it will be noted that the through-hole 4 of the fastening element 1a, 1b, 1c is configured in order to contribute to controlling the displacement of the deformable portions 7, particularly to reduce this displacement, in such a way that the deformable portions 7 combined with the rigid portions 6 may store a maximum of elastic energy during the driving of the element 1a, 1b, 1c on the support element 3 and thus increase the holding of this element 1a, 1b, 1c on this element 3.
It will be noted that the elastic fastening element 1a, 1b, 1c by being provided with at least four contact areas 13, applies a contact pressure that is significantly reduced on the peripheral wall 10 of the support element 3 thus contributing to reducing the sensitivity of this element 1a, 1b, 1c to fracture and to chips.
With reference to
This deformation sub-step 21 of the method, comprises a phase of displacing 22 the deformable portions 7 under the action of the contact force F that is applied to them. Such a displacement of these deformable portions 7 is performed in a radial direction R in relation to the axis of revolution A common to the support element 3 and to the fastening element 1. The contact force F is preferably perpendicular or substantially perpendicular to said contact area 13. During the course of this phase 23, the rigid portions 6 do not deform.
This method subsequently comprises a step of fastening 23 the fastening element 1a, 1b, 1c on the support element 3. Such a fastening step 23 particularly by radial elastic clamping, comprises a sub-step of performing 24 a radial elastic clamping of the fastening element 1a, 1b, 1c on the support element 3. It is therefore understood that in such a state of constraint, the fastening element 1a, 1b, 1c stores a large amount of elastic energy that contributes to giving it a substantial holding torque particularly allowing an optimal twist by elastic clamping.
| Number | Date | Country | Kind |
|---|---|---|---|
| 22209690.1 | Nov 2022 | EP | regional |
