Inlaid watch component and its manufacturing process

Abstract

Inlaid watch component and its manufacturing process. The invention relates to an inlaid watch component (1) comprising a body (10) made of metallic and / or ceramic material having at least one recess (11) forming the impression of a decoration (12). According to the invention, said at least one recess is entirely filled by successive layers (13, 14, 15) formed by an agglomeration of particles (16) via cold metallization in order to form a watch component (1) inlaid with at least one decoration (12). Fig. 3

Description

Title of the invention: Inlaid watch component and its manufacturing process technical field

[0001] The invention relates to a watch component inlaid with at least one metallic and / or ceramic decoration and to its manufacturing process. Previous technique

[0002] It is known to form watch components such as watch bezels at least partially from ceramic, metal, or composite materials to display a deposit made in a recess beneath the bezel, forming, for example, a graduation mark or a trade name. This configuration has the advantage of protecting the deposit from any mechanical degradation by completely covering the sapphire portion. However, this configuration can make the design difficult to read due to the altered transmission of the deposit's color and also due to the lack of differentiation between the sapphire's hue and that of the deposit.

[0003] To overcome these drawbacks, an inlaid ceramic element has been proposed comprising a ceramic body having at least one recess forming the imprint of a decoration, said at least one recess being entirely filled by a first and a second electrically conductive layer of approximately 50 nm and a metallic galvanic deposit in order to form a ceramic element inlaid with at least one metallic decoration of improved visual quality.

[0004] However, manufacturing such a part remains complex, costly, and time-consuming, and it is necessary to apply a bonding layer (conductive layer) to create the decorations. Furthermore, it is difficult to perfectly fill the cavities forming a decoration or graduation while achieving a flawless visual appearance. Summary of the invention

[0005] The invention aims in particular to overcome the various drawbacks of the prior art.

[0006] To this end, the invention relates to an inlaid watch component comprising a body made of metallic and / or ceramic material having at least one recess forming the imprint of a design. According to the invention, said at least one recess is entirely filled by successive layers formed by an agglomeration of particles via cold metallization in order to form a watch component inlaid with at least one design.

[0007] In accordance with other advantageous variants of the invention: • the particles forming the layers are metallic and / or at least partially made of ceramic and are chosen from: copper, zinc, tin, titanium, niobium, zirconium, tantalum, chromium, iron and its alloys, zirconia or alumina; • each at least one recess has a depth of at least 100 pm, and preferably 200 pm; • at least one decoration is covered with a colored metallic layer by means of anodizing; A watch component is a finishing element such as a bezel, a case back, a dial, a case middle, a bracelet link, a crown, a pusher.

[0008] The invention also relates to a timepiece comprising at least one inlaid timepiece component according to the invention.

[0009] The invention also relates to a method for manufacturing an inlaid watch component comprising the following steps:

[0010] a) form a body of metallic and / or ceramic material;

[0011] b) engrave at least one recess in one face of the body in, each at least one obviously forming the imprint of a design;

[0012] c) depositing a first layer of a coating with a thickness of at least 1 Opm over the whole face comprising said at least one recess by cold spraying process, known as "cold spray", of a flux comprising a carrier gas and particles forming the coating;

[0013] d) repeat step c) one or more times to deposit one or more additional layers of 20pm each over the entire face having said at least one recess covering the first layer in order to completely fill said at least one recess and form an inlaid decoration;

[0014] e) perform a polishing to remove all deposits from the strata of the surface of the body so as to leave only in at least one recess.

[0015] In accordance with other advantageous variants of the process according to the invention: • the carrier gas flow has a flow rate between 85 and 90m3 / h, at a pressure between 45 and 60 bar and at a temperature between 800 and 1000°C; • the particles are made of metal or metal alloy, ceramic or cermets; • the mass flow rate of the particles is between 70 and 80g / min; • the maximum particle size is 45pm; • the particle size is between 1 and 25pm; • the process includes an optional step between steps b) and c) in which the recess is engraved or textured via a laser to improve particle adhesion; • the process includes an optional step after step e) in which anodizing of the decorations is carried out to color said decorations. Brief description of the drawings

[0016] Other features and advantages of the invention will become apparent from the following detailed description, given by way of non-limiting example, with reference to the accompanying drawings in which:

[0017] - Fig. 1 shows a cross-sectional view of a watch component covered with several layers;

[0018] - Figure 2 shows a cross-sectional view of a watch component according to the invention

[0019] - [Fig.3] represents a top view of a bezel for a watch part obtained via a process according to the invention. Detailed description

[0020] In the example illustrated in [Fig. 1], a watch component 1 can be seen. The inlaid watch component 1 comprises a body 10 made of metallic and / or ceramic material having at least one recess 11 forming the imprint of a decoration 12. The at least one recess 11 is completely filled by successive layers 13, 14, 15 formed by an agglomeration of particles 16 via a cold metallization, more commonly called "cold spray", in order to form a watch component 1 inlaid with at least one decoration 12.

[0021] The cold spray metallization technique consists of accelerating a feedstock material (300 to 1500 m / s) in powder or particle form beyond a critical speed. These speeds cause plastic deformation and / or fragmentation upon impact of this material on a substrate to be treated, which is sufficient to form a dense and adherent coating. The temperatures of the spray gases are low (typically between 300 and 1100 °C) compared to the temperatures used in other processes. The material before impact is therefore not melted. Ceramic materials can also be sprayed.

[0022] In the following description, only the case of a bezel 1 will be described, but it goes without saying that the description is applicable to any other watch component, and more particularly the finishing parts of a watch such as a case back, a dial, a case middle, a crown, an oscillating weight or even a pusher.

[0023] In the example illustrated below, the explanation of the invention will therefore be given from a ring 10 made of ceramic material having inlaid metallic decorations 12 forming the graduations of a bezel 4. Obviously a bezel made of metal or metallic alloy, cermet or even composite material is also possible.

[0024] The inlaid bezel 1 is intended to form a part that is very resistant to wear and includes at least one metallic decoration with excellent visual quality and improved durability over time.

[0025] As illustrated in [Fig. 2], the inlaid watch component 1 comprises a ceramic body 10 having at least one recess 11 forming the imprint of a decoration 12. In [Fig. 3], it can be seen that each decoration 12 can be of any shape, such as, for example, a geometric figure or an alphanumeric character. According to the invention, each recess 11 is completely filled by a plurality of layers 13, 14, 15 with a thickness of between 10 and 50 µm. This configuration makes it possible to protect each metallic decoration 12 within the ceramic body 10, which is highly resistant to wear.

[0026] Each recess 11 has a depth P between 100 and 200 pm and its internal surface can have a variety of geometric shapes. For example, one can imagine a recess in the shape of a star, a rectangle or a triangle, or even a letter.

[0027] The body 10 is obtained from a wide variety of materials, including ceramics. A zirconia-based ceramic is preferentially used for its mechanical properties, its polishability, and, to a lesser extent, for its ability to offer a wide range of colors. It is clear, of course, that other ceramics are possible, such as, for example, titanium carbide-based ceramics, or even transparent polycrystalline ceramics based on alumina or spinel.

[0028] According to another embodiment, the body 10 is obtained from a metallic material or a metallic alloy.

[0029] The particles forming the layers are metallic and / or at least partially ceramic and are selected from: copper, zinc, tin, titanium, niobium, zirconium, tantalum, chromium, iron, zirconia, or alumina. According to one embodiment of the invention, layers of different materials are used; for example, a first part of the layers may be made of zinc and then a second part of titanium. Such an alternative makes it possible to reduce manufacturing costs.

[0030] The first layer 13 has a thickness of approximately 20 µm and is located at the bottom of the recess 11. Similarly, the second layer 15 and subsequent layers have increasing or identical thicknesses, depending on the requirements of those skilled in the art. The first layer may, for example, have a thickness of 20 µm, the second layer 30 µm, the third 30 µm, the fourth 40 µm, the fifth 50 µm, and so on. The succession of layers continues until the recess is completely filled.

[0031] Furthermore, according to the invention, the visual appearance of each decoration 12 can be modified locally by coloring the last layer, namely the layer flush with the surface of the watch component, via an anodizing 16 for example, when the body 10 is made of ceramic.

[0032] In this respect, to facilitate anodizing, at least the last of the metallic layers is preferably made of aluminium or titanium.

[0033] In the case of a metallic body 10, the filling portion will not pose a problem, but coloring via localized anodic oxidation will not be feasible, as both the body 10 and the final layer are conductive. It is therefore possible to deposit the final layer slightly recessed from the surface of the body 10, then perform anodic oxidation on the entire part, and finally remove the excess from the surface of the body via a polishing operation, for example (another option: apply a mask using a LIG A process).

[0034] The invention also relates to a method for manufacturing an inlaid watch component.

[0035] The manufacturing process for an inlaid watch component 10 will now be explained. In the following description, only the case of manufacturing a bezel 1 will be described, but it is understood that the description is applicable to any other watch component as detailed previously. The explanation of the process according to the invention will therefore be given starting from a ceramic ring 10 having inlaid metallic decorations 12 forming the graduations of a bezel 1.

[0036] In a first step a), the process consists of forming the ceramic body 10, for example, from zirconia. In the case of a ceramic-based component, this is preferably obtained by sintering. At the end of step a), the body 10 has its final dimensions.

[0037] The process includes a second step b) for engraving at least one recess 11, which may be blind, in a face F of the body 10, the recesses 11 forming the impression of the future decorations 12 as shown in [Fig. 1]. Each recess 11 has a minimum depth P of 100 µm, and preferably a depth of 200 µm. Each recess 11 can have a various geometric shape depending on the needs of those skilled in the art. For example, one can imagine a recess in the shape of a star, a rectangle, or a triangle, or even an alphanumeric character.

[0038] Step b) is generally achieved by means of laser ablation, allowing for good engraving precision. According to an optional step, at the end of step b) at least one recess is engraved or textured via a laser to improve particle adhesion in the subsequent steps of the process.

[0039] The process continues according to a third step c) intended to deposit a first layer 13 of a thickness equal to 20pm on the whole of the face F, i.e. including in each of the recesses 11 as visible in [Fig.1].

[0040] The third step c) of the process consists of coating face F by cold metallization, more commonly known as "cold spray". It is thus possible to deposit a particle layer that adheres perfectly to body 10 without the presence of an adhesion layer.

[0041] The projected particles are made of metal or metal alloy, ceramic or cermets.

[0042] To form the deposit on the substrate 10, the particles are projected by means of a carrier gas through a de Laval type spray nozzle to accelerate them and project them at high speed to make them adhere to the substrate.

[0043] In the illustrated example, titanium particles of a size between 1 and 50 pm are projected, and preferably a particle size in the range of 5 to 25 pm, and even more preferably a size of 20 pm.

[0044] The main gas is delivered through the nozzle at a flow rate of between 80 and 90 m³ / hour, the flow rate being subject to variation depending on the nozzle and the gas used. Generally, helium and nitrogen are used alone or in combination. Helium has the advantage of allowing operation at lower temperatures than nitrogen, and nitrogen has the advantage of being less expensive.

[0045] The temperature of the carrier gas is in a range of 900°C to 1000°C, and the spray pressure is in a range of 45 to 60 bar.

[0046] In the case of titanium particles, a temperature of 1000°C and a pressure of 50 bar give very good results.

[0047] The particles are sent into the nozzle at a flow rate of 70 to 80 g / min, and preferably at a flow rate of 75 g / h. The velocity of the particles is thus between 800 and 1000 m / s.

[0048] The spray nozzle is kept at a distance of approximately 50mm from the surface F of the telescope 1 and progresses at a speed of 0.15m / sec during the deposit of each layer.

[0049] In the case of a ceramic substrate, those skilled in the art will ensure that the process parameters are adjusted during the deposition of the first layer. Ceramic material is relatively fragile, and the particles must be projected at a lower speed to avoid cracking and / or breaking the substrate. Thus, during the deposition of the first layer, the particles are sent into the nozzle at a flow rate of 20 g / min, while the pressure, flow rate, and temperature of the carrier gas remain constant.

[0050] The process continues with a fourth step d) in which step c) is repeated one or more times to deposit one or more additional layers 14,15 of at least 20pm each on the whole of the face F having at least one recess 11 covering the first layer 13. Step c) is repeated until the at least one recess 1 is completely filled and a decoration 12 is inlaid in the lunette 1.

[0051] Finally, in a fifth step e), the process ends by removing the layers 13, 14 and 15 are deposited on the surface F of the body 10, leaving only the area at each recess 11 as visible in [Fig. 2]. The inlaid watch component 10 is thus complete and may only need to be mounted on a final part. This can be achieved by a conventional surfacing method such as grinding or lapping to remove excess material, followed by polishing.

[0052] The process according to the invention may also include a final optional step for depositing a metallization in order to color the decorations 12. Such a layer can, for example, be produced via anodizing.

[0053] Of course, the present invention is not limited to the illustrated example and is susceptible to various variants and modifications which will appear to a person skilled in the art, without departing from the scope of the invention as defined by the claims.

Claims

Demands

1. Inlaid watch component (1) comprising a body (10) of metallic and / or ceramic material having at least one recess (11) forming the imprint of a decoration (12) characterized in that said at least one recess is entirely filled by successive layers (13, 14, 15) formed by an agglomeration of particles (16) via cold metallization in order to form a watch component (1) inlaid with at least one decoration (12).

2. Inlaid watch component (1) according to claim 1, wherein the particles (16) forming the layers are metallic and / or at least partially ceramic and are selected from: copper, zinc, tin, titanium, niobium, zirconium, tantalum, chromium, iron, zirconia or alumina.

3. Inlaid watch component (1) according to any one of claims 1 to 2, wherein each at least one recess (11) has a depth of 200 pm.

4. Inlaid watch component (1) according to any one of claims 1 to 3, characterized in that at least one decoration (12) is covered with a colored metallic layer (18) by means of anodizing.

5. Inlaid watch component (1) according to any one of claims 1 to 4, characterized in that the watch component is a dressing element such as a bezel, a case back, a dial, a case middle, a bracelet link, a crown, a pusher.

6. A timepiece characterized in that it comprises at least one inlaid timepiece component (1) conforming to one of the preceding claims.

7. A method for manufacturing an inlaid watch component (1) comprising the following steps: a) forming a body (10) of metallic and / or ceramic material; b) engraving at least one recess (11) in a face (F) of the body (10), each at least one recess forming the impression of a decoration (12); c) depositing a first layer (13) of a coating with a thickness of at least 1 Opm over the entire face (F) comprising said at least one recess by a cold spray process, using a flux comprising a carrier gas and particles (16) forming said coating; d) repeating step c) one or more times (14) to deposit a or several additional layers of 20pm each over the whole of the face (F) comprising said at least one recess covering the first layer (14) in order to completely fill said at least one recess and form an inlaid decoration (12); e) perform a polishing to remove all deposits of the layers from the surface of the body (10) in order to leave only in the at least one recess.

8. A method according to claim 7, characterized in that the carrier gas flow has a flow rate between 85 and 90m3 / h, a pressure between 45 and 60 bar and a temperature between 900 and 1000°C.

9. A method according to claim 7 or 8, characterized in that the particles are made of metal or metal alloy, ceramic or cermets.

10. A method according to any one of claims 7 to 9, characterized in that the mass flow rate of the particles is 70 to 80g / min.

11. A method according to any one of claims 7 to 10, characterized in that the particle size is at most 45pm.

12. A method according to any one of claims 7 to 11, characterized in that the particle size is preferably between 1 and 25pm.

13. A method according to any one of claims 7 to 12, characterized in that it comprises an optional step between steps b) and c) in which the recess is engraved or textured via a laser to improve particle adhesion.

14. A method according to any one of claims 7 to 13, characterized in that it comprises an optional step after step e) in which an anodizing of the decorations is carried out to color said decorations.

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