METHOD FOR MANUFACTURING A COMPONENT FOR A CLOCKWORK PART

Abstract

The invention relates to a method for manufacturing a component for a watch part, the component comprising a body having a recess in a longitudinal end face in which an insert is mounted, said method comprising: - A step of supplying a body (16) having a recess (26) formed in a longitudinal end face, said recess (26) having a given outer contour (C) in the longitudinal end face, - A step of supplying a pellet having a shape homothetic to the shape of the given outer contour (C) and of dimensions allowing its placement in the recess (26), - A cold-forming step so as to deform the pellet so that it conforms to the given outer contour C of the recess (26). [Fig. 4]

Description

Title of the invention: METHOD FOR MANUFACTURED A COMPONENT FOR A CLOCKWORK PART TECHNICAL FIELD AND PREVIOUS ART

[0001] The present invention relates to a watch part component, such as a winding crown, a pusher or corrector, a bezel or any other component implemented in a watch part, more particularly to a control component for a watch part and to a watch part comprising such a component.

[0002] A watch crown is generally located on the side of the watch case and mechanically interacts with the mechanical watch movement housed within the case, for example, to wind the mainspring and / or to set the time. The crown is connected to the mechanical watch movement in a known manner. The crown is intended to be mounted on a tube fixed to the watch case and is intended to be grasped by the watch user to operate the mechanical movement.

[0003] The crown generally has a cylindrical shape with a circular cross-section, comprising a side wall, a first longitudinal end on the side of the box, and a second free longitudinal end that is visible. The side wall may or may not be grooved.

[0004] Typically, the free longitudinal end of the crown bears a symbol or logo that is generally representative of the watch manufacturer. The crown is a single piece, and the logo is embossed into the crown, for example, by machining. This can be a complex process. Furthermore, the manufacturing process for crowns made of two materials is even more complex. Description of the invention

[0005] It is therefore one of the aims of the present application to provide a simplified manufacturing process for a watch component while offering a high level of finish.

[0006] The stated objective is achieved by a method for manufacturing a component of a timepiece, said method comprising: - The supply of a body comprising a first end intended to be on the side of the timepiece and a second longitudinal end opposite the first longitudinal end, the second end comprising a recess including a contour of a given shape, - The supply of a pellet whose external shape corresponds to the given contour shape, - The placement of the pellet in the recess, - A cold-forging step to deform the pellet and fix it in the body.

[0007] Thanks to the invention, the manufacturing process is simplified since the constraints on the play are relieved. Indeed, the striking step deforms the pellet that fills the recess. The production of the pellet therefore requires less precision.

[0008] Furthermore, thanks to the stamping process, the material of the disc conforms to the shape of the recess, which provides a remarkable aesthetic effect. In addition, the invention allows for the combination of different materials, such as steel for the head and gold for the logo.

[0009] Furthermore, the pellet is not likely to separate from the body.

[0010] The invention makes it possible to produce crowns with discs of relatively complex shapes.

[0011] Advantageously, during the typing process a logo is simultaneously produced on the disc.

[0012] The present invention relates to a method for manufacturing a component for a watch part, said component comprising a body having a recess in a longitudinal end face, in which an insert is mounted, said method comprising: - A step of supplying a body having a recess formed in a longitudinal end face, said recess having a given external contour in the longitudinal end face, - A step involving the supply of a pellet with a shape homothetic to the shape of the given outer contour and dimensions allowing its placement in the recess, - A cold-forging step to deform the pellet so that the pellet conforms to the given outer contour of the recess.

[0013] Most advantageously, during the cold stamping stage, a logo is formed on the surface of the pellet.

[0014] In a preferred example, the body supply step includes a body manufacturing step comprising the making of the recess which includes an internal portion on the side of a bottom of the recess and an external portion delimited by the given external contour, the internal portion having a larger cross-section than the external portion so as to delimit a groove bordering the internal portion.

[0015] Preferably, the pellet supply step includes the manufacture of the pellet, said pellet having a beveled edge, said beveled edge being intended to be oriented towards a punch implemented during the cold striking step.

[0016] In the case of a body having a lateral edge with grooves, during the cold forging step, a finishing step of the grooves can be carried out.

[0017] The present invention also relates to a watch part organ obtained by the manufacturing process according to the invention, comprising a body having a recess in a longitudinal end face, said recess having a given outer contour in the longitudinal end face and an insert mounted in the recess, said insert conforming to the given outer contour following a mechanical deformation.

[0018] Preferably, said recess at its base has a peripheral groove and the insert has a peripheral heel housed in the peripheral groove.

[0019] The peripheral groove advantageously comprises a longitudinal edge opposite the bottom, said longitudinal edge being inclined in the direction of the longitudinal end face.

[0020] The body and the insert can be made of different materials.

[0021] The organ is for example a control organ, for example a crown.

[0022] The present invention also relates to a timepiece comprising at least one component according to the invention. Brief description of the drawings

[0023] This application will be better understood with the aid of the following description and the attached drawings, in which: - Fig. 1 is a perspective view of an example of a crown obtained by a manufacturing process according to an example of embodiment, - Fig. 2 is a longitudinal cross-sectional view along plane AA of the crown of Fig. 1. - Fig. 3 is a perspective view of the head used to make the crown of Fig. 1. - Fig. 4 is a longitudinal cross-sectional view along plane BB of the head of Fig. 3. - Fig. 5 is a top view of the head of Fig. 3. - Fig. 6 is a perspective view of a pellet used to manufacture the crown of Fig. 1. - Figure 7 is a top view of the pellet in Figure 6. DETAILED DESCRIPTION OF IMPROVEMENTS

[0024] In the following description, the manufacturing process according to the invention will be described in the context of manufacturing a watch crown, but the invention applies to the manufacture of any component of a watch, for example, a pusher, a corrector, a bezel, or a rotor. The invention is particularly interesting in its application to the manufacture of a control mechanism for a watch.

[0025] A timepiece includes a watch case, a dial, hands, a crystal and a clockwork mechanism located in the watch case and a crown generally mounted on one side of the watch case and mechanically connected to the clockwork mechanism, for example to set the time.

[0026] Figures 1 and 2 show an example of a crown obtained by a manufacturing process according to an example embodiment.

[0027] The crown 14 extends along the longitudinal axis Y which is orthogonal to the axis of the timepiece.

[0028] The crown 14 is intended to cooperate with a tube fixed to the watch case and through which passes the winding stem of the watch mechanism.

[0029] The crown 14 comprises a body 16 or head of cylindrical shape of revolution with geometric longitudinal axis Y.

[0030] The head has a lateral surface 21 which, in this example, is grooved.

[0031] The crown 14 has an insert 22 mounted in a second longitudinal end 24 of the head. This second end, fitted with the insert, is intended to be visible. In this example, the insert has a raised S symbol or logo.

[0032] The head material and the disc material are metallic and may be identical or different. Thanks to the invention, it is possible to produce a crown, and more generally a component for a timepiece, that presents an aesthetic contrast using different materials. Furthermore, the invention allows for the combination of materials with different production costs. For example, the head is made of steel and the disc is made of gold.

[0033] Figures 3 to 5 show an example of a crown head before assembly, and figures 6 and 7 show an example of a pellet configured to be assembled by cold forging into the crown head of figures 3 to 5.

[0034] The crown head has in its second longitudinal end 24 a recess 26 of given external contour C.

[0035] In [Fig.4], one can see the recess 26 comprising an internal portion 28 and a external portion 30.

[0036] The internal portion 28 is located on the bottom side of the recess and the external portion 30 is located on its open end and opens outwards. The portion external is located above the internal portion along the longitudinal axis Y in the representation of [Fig.4].

[0037] The external portion 30 is delimited by the given external contour C.

[0038] The internal portion 28 has a cross-section along a plane orthogonal to The longitudinal axis Y is larger than the cross-section along a plane orthogonal to the Y axis of the external portion 30. The internal portion 28 is arranged relative to the external portion 30 such that the lateral edge 32 of the internal portion 28 is recessed relative to the contour C when considering a direction orthogonal X to the longitudinal axis Y. A groove 33 is thus formed under the external contour C.

[0039] The cross-section of the internal portion 28 has a shape substantially similar to that of the external portion, so that the depth of the groove in the X direction varies little over the entire contour of the internal portion. The depth of the recess is typically less than 1 mm.

[0040] In this example and preferably, the internal portion 28 connects to the external portion 30 by an inclined face 34 so that the groove 33 opens in the direction of the longitudinal axis Y. This inclination facilitates the filling of the groove by the material of the pellet.

[0041] In one embodiment, the recess is machined. In another embodiment, the crown body with the recess is 3D printed.

[0042] The pellet 36 has an external shape substantially homothetic to the shape of the given external contour C and smaller in size than the shape of the external contour, so that the pellet can be positioned in the recess. The sides of the pellet have dimensions smaller than the dimensions of the edges of the recess.

[0043] In the example shown, the outer contour C has angles 38. Advantageously, the pellet has corresponding beveled angles 39 to facilitate its placement in the recess. The bevels have the advantage of reducing the risk of snagging between the counterform of the punch and the pellet.

[0044] Preferably, the upper edge 40 of the pellet, which is intended to be in initial contact with the punch, is beveled as shown in [Fig. 6]. This beveled upper edge is designed to cooperate with the counterform and ensure the alignment of the pellet and the punch. Indeed, the counterform has inclined lateral edges which, by cooperating with the beveled upper edge, ensure alignment of the pellet and the punch.

[0045] The dimensions of the pellet, in particular its thickness, are chosen according to the dimensions of the recess, in particular the groove and the visual appearance that one wishes to achieve on the pellet.

[0046] In the example shown in [Fig. 1], the final ring has a raised pattern. The thickness of the pellet is chosen to be sufficient, on the one hand, during cold forming to at least partially fill the groove and the entire outer portion, and on the other hand, to allow sufficient material for the raised pattern.

[0047] The manufacturing process for the crown will now be described. This process employs cold forging. Cold forging consists of rapidly deforming a blank of material, generally a metallic material, under high pressure. Cold forging is also called cold forming.

[0048] The head is placed in a matrix which holds it.

[0049] The pellet is placed in the recess 26.

[0050] The pellet is then assembled onto the head by cold forging. For this purpose, a punch applies pressure to the pellet towards the bottom of the recess, which deforms the pellet material, causing it to conform to the shape of the recess, in particular filling at least part of the groove and completely filling the external portion of the recess. The pressure exerted is on the order of several tons.

[0051] The hallmark includes a counterform of the upper part of the crown including the S logo.

[0052] In this example, the punch has in relief the pattern to be formed in relief when striking the pellet.

[0053] The material of the pellet, by filling at least part of the groove 33, ensures that the pellet remains in the recess.

[0054] The crown shown in figures 1 and 2 is obtained.

[0055] The assembly can be obtained in one or more passes.

[0056] Alternatively, the throat is discontinuous.

[0057] Thanks to the invention, the material of the disc conforms perfectly to the outer contour C, thus visually eliminating the gaps that usually exist in the assembly. The manufacturing process according to the invention therefore makes it possible to produce crowns, and more generally components for watch parts, offering a high level of finish while simplifying their manufacture.

[0058] It is possible to consider that a recessed pattern relative to the free surface of the head is made or that the pellet has a smooth surface which is flush with the free surface of the head.

[0059] The metal or metal alloy of the head may have a greater or lesser hardness than the metal or metal alloy of the pellet.

[0060] In one embodiment, the grooves and / or other patterns on the lateral surface of the crown are made by turning and then undergo a finishing step simultaneously with or just before or just after the striking step using the die.

[0061] It will be understood that the process according to the invention makes it possible to produce crowns of other shapes.

[0062] Furthermore, the method according to the invention also allows for the manufacture of a pusher or a corrector. The present invention also applies, without limitation, to the manufacture of a weight or to the manufacture of a bezel for a watch component. In the case of a bezel, the disc can be inserted at a given location on the bezel or around the entire circumference of the bezel, the resulting recess then being substantially annular in shape.

[0063] Furthermore, the insert can be of any shape. The insert can have a round shape, a polygonal shape, a shape with curves, and a shape combining straight and curved parts.

[0064] The head may not have a shape of revolution and may be, for example, square or otherwise shaped.

Claims

Demands

1. A method for manufacturing a watch component, said component comprising a body having a recess in a longitudinal end face, in which an insert is mounted, said method comprising: - A step of supplying a body (16) having a recess (26) formed in a longitudinal end face, said recess (26) having a given outer contour (C) in the longitudinal end face, - A step of supplying a pellet (36) having a homothetic shape of the given outer contour (C) and of dimensions enabling its placement in the recess (26), - A cold-forming step so as to deform the pellet (36) and that the pellet conforms to the given outer contour (C) of the recess (26).

2. A manufacturing method according to claim 1 wherein, during the cold stamping step, a logo is formed on the surface of the pellet.

3. A manufacturing method according to claim 1 or 2, wherein the body supply step comprises a body manufacturing step including the making of the recess which includes an internal portion (28) on the side of a bottom of the recess and an external portion (30) delimited by the given external contour (C), the internal portion (28) having a larger cross-section than the external portion (30) so as to delimit a groove (33) bordering the internal portion (28).

4. A manufacturing method according to any one of the preceding claims, wherein the pellet supply step comprises the manufacture of the pellet, said pellet having a beveled edge (40), said beveled edge being intended to be oriented towards a punch implemented during the cold forging step.

5. A manufacturing method according to any one of the preceding claims, the body having a lateral edge with grooves, in which, during the cold forging step, a finishing step of the grooves is carried out.

6. A watch component obtained by the manufacturing process according to any one of the preceding claims, comprising a body (16) having a recess (26) in a longitudinal end face, said recess (26) having a given outer contour (C) in the longitudinal end face and an insert mounted in the recess, said insert conforming to the given outer contour following a mechanical deformation.

7. A watch part according to claim 6, wherein said recess (26) at its base has a peripheral groove and the insert has a peripheral heel housed in the peripheral groove.

8. A watch part component according to claim 7, wherein the peripheral groove has a longitudinal edge opposite the bottom, said longitudinal edge being inclined towards the longitudinal end face.

9. A watch part component according to any one of claims 6 to 8, wherein the body and the insert are made of different materials.

10. A watch part component according to any one of claims 6 to 9, wherein the component is a control component, for example a crown.

11. Timepiece comprising at least one component according to any one of claims 6 to 10.