CH718233B1 - Wristwatch component, wristwatch and method of manufacturing a wristwatch component. - Google Patents

Abstract

Disclosed is a wristwatch component which, although made of a diamond single crystal, is resistant to external impact force, can be easily shaped, and can add decoration; a method of manufacturing the wristwatch component; and a wristwatch including the wristwatch component. For this purpose, a diamond single crystal is prepared whose plan shape is quadrilateral, circular or circular with an orientation flat, the quadrilateral shape having a side length of 10.0 mm or more, the circular shape having a diameter 10.16 mm or more. The diamond crystal is subjected to laser cutting to form at least a part of the outline of the wristwatch component with circular (2) or elliptical arcs arranged at a pitch (P1) of between 330 μm and 420 μm, and removing then the wristwatch component of the diamond crystal. Subsequently, the wristwatch component separated from the diamond crystal is polished to thereby finish and manufacture the wristwatch component. Further, a wristwatch is composed by installing the wristwatch component therein.

Description

TECHNICAL AREA

The present invention relates to a wristwatch component, a wristwatch, and a method of manufacturing a wristwatch component.

STATE OF THE ART

[0002] Patent applications have been filed for movement components of wristwatches (in particular mechanical wristwatches) made of diamond crystals (see, for example, patent document 1: EP2037335B1).

[0003] Mechanical wristwatches, such as those with a tourbillon, can be constructed in such a way that the movement components, in particular, are visible from outside the wristwatch (skeleton), thus offering the user of the wristwatch the pleasure of seeing the movement components and adding luxury and decoration to the wristwatch. Therefore, the movement components made of diamond crystal are expected to add all the more luxury and decoration to the wristwatch.

[0004] In addition to the movement components, a patent application has also been filed for a protective cover, which is a protective component of a wristwatch, made of diamond crystals (see, for example, the patent document 2: JP2012150099A). Thus, the use of diamond crystals not only for movement components but also for external components such as the protective cover (referred to as protective glass in patent document 2) adds even more luxury and decoration to the wristwatch.

SUMMARY OF THE INVENTION

The present invention is set out in the appended claims.

PROBLEM TO BE SOLVED BY THE INVENTION

[0006] Diamond crystals are scratch resistant due to their high Mohs hardness. However, among gemstones, ruby and sapphire crystals have greater resistance to impact forces, while diamonds have lower resistance and are therefore less resistant to external impact forces than rubies and diamonds. sapphires. Therefore, if the user knocks the wristwatch against something or drops it inadvertently, so that an impact force is applied from outside the wristwatch, cracks, splits, Chips or chips can occur in watch components made from diamond crystals.

[0007] Due to these concerns, diamond crystals have not been used in wristwatches as much as sapphire crystals, for example, which have already been used in wristwatches for, for example, the protection cover.

[0008] Furthermore, since diamond crystals are the hardest material of all gemstones, they are more difficult than other gemstones to form into precision components, such as components of wristwatch movements. This is one of the reasons why diamond crystals have not been widely used in wristwatches.

[0009] The present invention has been made in view of the aforementioned problem, and aims to provide a component for a wristwatch (wristwatch component) which is resistant to impact forces applied from the outside, although it is made of diamond crystal, which can be easily shaped, and can add decoration, a manufacturing method of the wristwatch component, and a wristwatch equipped with the wristwatch component.

WAYS TO SOLVE THE PROBLEM

The aforementioned problem is solved by the present invention described below. The wristwatch component according to the present disclosure is characterized in that it consists of a diamond crystal and that its outline is formed at least partially by circular or elliptical arcs arranged at a pitch of between 330 μm and 420 µm.

[0011] The wristwatch according to the present disclosure is characterized in that it is equipped with the aforementioned wristwatch component.

[0012] The manufacturing method of the wristwatch component according to the present disclosure is characterized in that it comprises the following steps: the preparation of a diamond crystal whose plan shape is quadrilateral, circular or circular with a orientation plate, the quadrilateral shape having a side length of 10.0 mm or more, the circular shape having a diameter of 10.16 mm or more; laser cutting the diamond crystal to form at least part of the outline with circular or elliptical arcs arranged at a pitch between 330 µm and 420 µm, followed by separating the wristwatch component from the diamond crystal; and polishing the wristwatch component separated from the diamond crystal to thereby finish and manufacture the wristwatch component.

ADVANTAGEOUS EFFECTS OF THE INVENTION

[0013] According to the wristwatch component and the method of manufacturing the wristwatch component of the disclosure, by forming at least a part of the outline of the wristwatch component to be installed in a wristwatch with a plurality of circular arcs or elliptical arcs arranged, at least part of the contour is formed by a plurality of arcs. Even though impact forces are applied from outside the wristwatch, they are distributed and not concentrated at a single point, preventing any cracks, splits, crazing, chips or chips from forming. produce, although the wristwatch component is made of diamond crystal.

[0014] Furthermore, each circular or elliptical arc being subjected to a compressive force coming from the interior of the diamond crystal which constitutes the wristwatch component, it is resistant to the impact forces applied from the exterior of the wristwatch component. This also helps to prevent cracks, splits, crazing, chipping or chipping.

[0015] Further, by setting the pitch as fine as between 330 μm and 420 μm, the impact force applied from the outside of the wristwatch component can also be distributed by a plurality of arcs, which makes it possible to prevent with greater certainty that cracks, splits, cracks, chips or chips do not occur.

[0016] Furthermore, by adjusting the pitch of the circular or elliptical arcs between 330 μm and 420 μm, the circular or elliptical arcs cannot be discerned with the naked eye by the user of the wristwatch. Consequently, even if the laser-cut portion is used as it is to form at least part of the contour of the wristwatch component, the aesthetics are not altered to the naked eye. The wristwatch component can therefore be designed in such a way as to give it a decorative appearance.

[0017] In addition, the step of shaping the wristwatch component is facilitated, since it is not necessary to provide a specific step for contouring after the laser cutting step.

[0018] The present disclosure also makes it possible to produce a wristwatch equipped with the wristwatch component exhibiting the aforementioned effects.

BRIEF DESCRIPTION OF DRAWINGS

[0019] [Fig. 1(a)] A front view of an exemplary movement component for a mechanical wristwatch according to one embodiment of the invention. [Fig. 1(b)] A right side view of Figure 1(a). [Fig. 2(a)] An enlarged view of part A circled in Figure 1. [Fig. 2(b)] A perspective view of Figure 2(a). [Fig. 3(a)] A large scale partial view of a variation of the component shown in Figure 2(a). [Fig. 3(b)] A perspective view of Figure 3(a). [Fig. 4(a)] A large scale partial view of another variation of the component shown in Figure 2(a). [Fig. 4(b)] A perspective view of Figure 4(a). [Fig. 5] A large-scale partial view of part B circled in Figure 4(a). [Fig. 6(a)] A large scale partial view of yet another variation of the component shown in Figure 2(a). [Fig. 6(b)] A perspective view of Figure 6(a). [Fig. 7] A large-scale view of part C circled in Figure 6(a). [Fig. 8(a)] A front view of an example of diamond crystal used as the base material for the motion component shown in Fig. 1. [Fig. 8(b)] A right side view of Figure 8(a). [Fig. 9(a)] A front view of a variation of the base material shown in Figure 8(a). [Fig. 9(b)] A front view of another variation of the base material shown in Figure 8(a). [Fig. 10] An SEM image which represents on a large scale part of the outline of a movement component for a mechanical wristwatch according to an exemplary implementation of the invention. [Fig. 11] An SEM image which represents on a large scale part of the contour of a movement component for a mechanical wristwatch according to another example of implementation of the invention.

MODE FOR CARRYING OUT THE INVENTION

[0020] According to a first characteristic of this embodiment, the wristwatch component consists of a diamond crystal and its outline is formed at least partially by circular or elliptical arcs arranged at a pitch between 330 μm and 420µm.

[0021] According to a second feature of the present embodiment, the process for manufacturing the wristwatch component comprises the following steps: preparing a diamond crystal whose plan shape is quadrilateral, circular or circular with a flat orientation, the quadrilateral shape having a side length of 10.0 mm or more, the circular shape having a diameter of 10.16 mm or more; laser cutting the diamond crystal to form at least part of its outline with circular or elliptical arcs arranged at a pitch between 330 µm and 420 µm, followed by separating the wristwatch component from the diamond crystal; and polishing the wristwatch component separated from the diamond crystal to thereby finish and manufacture the wristwatch component.

[0022] According to the structure and manufacturing method described above, by forming at least a part of the outline of the wristwatch component to be installed in a wristwatch with a plurality of circular arcs or elliptical arcs arranged , at least a part of the contour is formed by a plurality of arcs. Even though impact forces are applied from outside the wristwatch, they are distributed and not concentrated at a single point, preventing any cracks, splits, crazing, chips or chips from forming. produce, although the wristwatch component is made of diamond crystal.

[0023] Furthermore, each circular or elliptical arc being subjected to a compressive force coming from the interior of the diamond crystal which constitutes the wristwatch component, it is resistant to the impact forces applied from the exterior of the wristwatch component. This also helps prevent cracks, splits, crazing, chipping or chipping.

[0024] Further, by setting the pitch as fine as between 330 µm and 420 µm, the impact force applied from the outside of the wristwatch component can also be distributed by a plurality of arcs, which makes it possible to prevent with greater certainty that cracks, splits, cracks, chips or chips do not occur.

[0025] By adjusting the pitch of the circular or elliptical arcs between 330 μm and 420 μm, the circular or elliptical arcs cannot be discerned with the naked eye by the user of the wristwatch. Consequently, even if the laser-cut portion is used as it is to form at least part of the contour of the wristwatch component, the aesthetics are not altered to the naked eye. The wristwatch component can therefore be designed in such a way as to give it a decorative appearance.

[0026] In addition, the step of shaping the wristwatch component is facilitated, since it is not necessary to provide a specific step for contouring after the laser cutting step.

[0027] According to a third feature of this embodiment, the diamond crystal has a side length between 10.0 mm and 203.2 mm if the diamond crystal is of a quadrilateral shape in plan, or the crystal diamond crystal has a diameter between 10.16 mm and 203.2 mm if the diamond crystal is, in plan, of a circular shape or of a circular shape with an orientation flat in accordance with the manufacturing process of the component of wrist watch.

[0028] In addition to the effects described above, this manufacturing method can prepare a large diamond crystal as a base material for the wristwatch component, thereby making it possible to manufacture a large wristwatch component.

By diamond crystal is meant, for the purposes of the present disclosure, a single crystal, a polycrystal or a crystal having an intermediate structure between a single crystal and a polycrystal.

According to a fourth feature of this embodiment, the wristwatch component has a thickness of between 0.3 mm and 3.0 mm.

[0031] According to a fifth feature of this embodiment, the wristwatch component has a thickness of between 0.3 mm and 3.0 mm in accordance with the manufacturing method of the wristwatch component.

The structure and the manufacturing method described above make it possible to form the wristwatch component which is self-supporting although made of diamond crystal.

[0033] By self-supporting wristwatch component is meant, for the purposes of the present disclosure, a wristwatch component which can not only retain its own shape, but is also strong enough not to cause inconvenience during handling. The thickness should preferably be 0.3 mm or more in order to have sufficient strength and rigidity to prevent breakage, breakage or cracking.

[0034] Since diamond crystal is an extremely hard material, the upper limit of the thickness of the self-supporting wristwatch component is preferably 3.0 mm or less, in view of the difficulty of shaping or the like when formation of the wristwatch component.

According to a sixth characteristic of this embodiment, the wristwatch component has a surface roughness Ra of 0.1 μm or less.

[0036] According to a seventh characteristic of this embodiment, the wristwatch component must have a surface roughness Ra of 0.1 μm or less in accordance with the manufacturing method of the wristwatch component.

[0037] According to the structure and the manufacturing method described above, by setting Ra to 0.1 μm or less, the scattering of light on the surface of the wristwatch component is prevented, and the gloss without the haze is reached. Therefore, the aesthetics, luxury and decoration of the wristwatch component are high.

[0038] According to an eighth characteristic of this embodiment, the wristwatch component does not present any of the following problems: grain boundaries, black spots, crystalline defects, or zones of machining alteration.

[0039] According to a ninth feature of this embodiment, the process for manufacturing the wristwatch component comprises either a step of preparing a diamond crystal that does not have any of the following problems: grain boundaries, black spots, crystalline defects, or zones of machining alteration; or a step in the separation of the wristwatch component from a part of the diamond crystal which does not present any of the following problems: grain boundaries, black spots, crystalline defects, or areas of machining alteration.

[0040] According to the structure and the manufacturing process described above, the wristwatch component thus produced does not have grain boundaries, black spots, crystalline defects, or machining alteration zones, which elevates the aesthetics of the wristwatch component.

By crystalline defects is meant, for the purposes of this disclosure, twins, dislocations and distortions.

[0042] According to a tenth feature of this embodiment, the crystal plane in the plane direction is a (100) plane in the wristwatch component.

[0043] According to an eleventh feature of the present embodiment, the crystal plane in the direction of the diamond crystal plane is a (100) plane according to the manufacturing method of the wristwatch component.

[0044] According to the structure and the manufacturing method described above, by setting the crystal plane of the finished surface of the wristwatch component to (100), the formation of machining alteration zones can be prevented on the finished surface. Further, even if machining alteration areas are formed on the crystal plane, the removal of the machining alteration areas is easy, thereby elevating the aesthetics of the wristwatch component.

[0045] According to a twelfth feature of the present embodiment, there is provided a wristwatch equipped with any of the aforementioned wristwatch components.

[0046] This structure makes it possible to produce a wristwatch equipped with a wristwatch component having the aforementioned effects.

Referring to Figures 1 to 9, there will be described below a wristwatch component, its manufacturing process and a wristwatch equipped with this wristwatch component.

[0048] The wristwatch component according to the present disclosure comprises a protective cover to protect the dial and a movement component for mechanical wristwatches. The movement component also includes components for complicated mechanisms, such as tourbillons. More specifically, the wristwatch component may be, for example, a tourbillon movement component, a bearing, an anchor, a hair spring, a balance spring, a plate (bottom plate), a bridge (bridge), a lever (lever), a balance (wheel), a pallet assembly (pallet assembly), a plate (plate) and a dial (dial).

Figure 1 shows a component of the upper floor (upper deck) of the cage (cage) as an example of this embodiment. The wristwatch component 1 according to the present embodiment is made of a diamond crystal, the contour of which is entirely or at least partially formed by arranged circular or elliptical arcs. Figure 2 shows a large-scale view of the circled part A of the outline shown in Figure 1. The hatching of Figures 2 to 7 shows the surface of the wristwatch component 1 as it appears on the outside, and not a sectional view.

The diamond crystal used to form the wristwatch component can be chosen, for example, from single crystals, polycrystals and crystals having intermediate structures between them. However, the invention is limited to single crystals which are preferred because they are more transparent and do not detract from the aesthetics, luxury and decoration of the wristwatch component.

[0051] Further, the diamond crystal to form the wristwatch component 1 must not have any of the following problems: crystal defects, such as grain boundaries, black spots, dislocations, twins, and distortions, as well as chippings , cracks, splits, crazing, chips or areas of machining alteration. The wristwatch component 1 formed, which does not have grain boundaries, black spots, crystal defects or machining degradation areas, makes it possible to elevate the aesthetics of the wristwatch component 1. By machining alteration zones, we mean the atomically disordered crystalline zones, including dislocations, caused by machining on the main face of a machine-polished diamond crystal and in the zone of near thickness. of this main face. The presence or absence of machining alteration zones can be measured, for example, by synchrotron X-ray topography.

[0052] Since the aforementioned machining alteration areas are caused by the mechanical polishing step, the main face of the diamond crystal (i.e. the crystal plane 4 of the wristwatch component 1) after the mechanical polishing stage is subjected to a CMP (Chemical Mechanical Polishing) to remove the areas of machining alteration from the main face. The diamond crystal forming the wristwatch component 1 may be a colored diamond.

[0053] The crystal plane 4 in the direction of the plane of the wristwatch component 1 is a (100) plane, which is also the finished surface of the wristwatch component 1. If the wristwatch component 1 consists of a diamond single crystal, the orientation of the crystal plane 4 can be any one of (111), (110) and (100) and is not limited to these plane orientations. However, by setting the crystal plane 4 to (100), it is possible to use the diamond substrate which is originally intended to be used to form semiconductor elements or semiconductor devices, which makes it possible to plan the productivity increase of diamond crystal used as base material of wristwatch component 1.

Furthermore, by using the (100) plane as crystal plane 4, the formation of machining alteration zones on the finished surface can be prevented. In addition, even though a machining alteration zone is formed on the crystal plane 4, it has been observed that the machining alteration zone is formed across the (100) plane when the (100) plane is used as the crystal plane 4. Therefore, since the machining alteration zone is exposed on the surface of the main face, it is possible to remove it easily by CMP, which makes it possible to elevate the aesthetics of the component from wristwatch 1. In view of the above, although it is possible to perform the shaping, thickening and finishing polishing of the wristwatch component 1 by the mechanical polishing, it is desirable to use the CMP as the finishing step, because the zones of machining alteration can penetrate into the crystalline plane 4 during mechanical polishing.

[0055] The surface roughness Ra of the surface appearing outside the wristwatch component 1, including the crystal plane 4, should be 0.1 μm or less. In order to obtain a surface roughness Ra = 0.1 µm or less, mirror polishing by CMP is applied. Ra can be measured using a surface roughness tester. Ra set to 0.1 µm or less prevents light scattering on the surface of the wristwatch component 1 and achieves gloss without haze. Therefore, the aesthetics, luxury and decoration of the wristwatch component 1 are high.

[0056] Referring now to Figure 2, the circular arcs 2 forming at least part of the outline of the wristwatch component 1 will be described below. The pitch P1, which is fixed along the contour, represents the distance between the corresponding points on the two adjacent circular arcs 2.2. The diameter of each circular arc 2 is between approximately 330 μm and 420 μm. A plurality of circular arcs 2 are arranged along the contour to form at least part of the contour of the wristwatch component 1. The pitch P1 between the circular arcs 2 is between 330 μm and 420 μm.

[0057] The circular arcs forming the contour of the wristwatch component 1 can be modified into elliptical arcs 3, as shown in Figure 3. The pitch P2, which is fixed along the contour, represents the distance between the corresponding points on the two adjacent elliptical arcs 3.3. The major diameter of the elliptical arcs 3 is between about 330 μm and 420 μm and the minor diameter is between about 280 μm and 300 μm.

[0058] In addition, a plurality of elliptical arcs 3 are arranged along the outline to form at least part of the outline of the wristwatch component 1. The pitch P2 between the elliptical arcs 3 is between 330 μm and 420 µm.

[0059] By forming at least part of the contour of the wristwatch component 1 to be installed in a wristwatch with a plurality of circular arcs 2 or elliptical arcs 3 arranged, at least part of the contour is formed by a plurality of arcs. Even though impact forces are applied from outside the wristwatch, they are distributed and not concentrated at a single point, preventing any cracks, splits, crazing, chips or chips from forming. produce, although the wristwatch component 1 is made of diamond crystal.

[0060] Furthermore, each circular 2 or elliptical 3 arc being subjected to a compressive force coming from the interior of the diamond crystal which constitutes the wristwatch component 1, it is resistant to the impact forces applied from the exterior of the wristwatch component 1. This also helps to prevent cracks, splits, crazing, chipping or chipping.

[0061] Further, by setting the pitch P1 or P2 as fine as between 330 μm and 420 μm, the impact force applied from the outside of the wristwatch component 1 can be distributed by a plurality of arcs . This makes it possible to prevent with greater certainty the formation of cracks, splits, cracks, chips or chips in the wristwatch component 1.

[0062] The circular 2 or elliptical 3 arcs should preferably be arranged for such a portion of the contour in the wristwatch component where its resistance and toughness to external impact forces are insufficient, such as, for example, a portion that is relatively thin or that is shaped at an acute angle.

Furthermore, by adjusting the pitch P1 or P2 between 330 μm and 420 μm, the circular 2 or elliptical 3 arcs cannot be discerned with the naked eye by the user of the wristwatch. Consequently, even if the laser-cut portion, as will be seen below, is used as it is for at least part of the contour of the wristwatch component 1, the aesthetics is not altered to the eye. naked. It is therefore possible to design the wristwatch component 1 in such a way as to give it a decorative appearance.

[0064] In addition, the step of shaping the wristwatch component 1 is facilitated, since it is not necessary to provide a contouring step on purpose after the laser cutting.

[0065] The thickness t of the wristwatch component 1 can be fixed at will, but by fixing it between 0.3 mm and 3.0 mm, it is possible to form a self-supporting wristwatch component, although be made of diamond crystal. By self-supporting wristwatch component is meant a wristwatch component that can not only maintain its own shape, but is also strong enough not to cause inconvenience during handling. The thickness t should preferably be 0.3 mm or more in order to have sufficient strength and rigidity to prevent breakage, breakage or cracking.

[0066] Since diamond crystal is an extremely hard material, the upper limit of the thickness t of the self-supporting wristwatch component is preferably 3.0 mm or less, considering the ease of shaping or the like when the formation of the wristwatch component. Therefore, the thickness t of the wristwatch component 1 is set between 0.3 mm and 3.0 mm.

[0067] The wristwatch component 1 made of a diamond crystal as described above is installed in a wristwatch. According to this wristwatch, a wristwatch can be realized which is equipped with the wristwatch component 1 having the aforementioned effects. In addition, by making the movement component visible from the outside of the wristwatch, the structure of the wristwatch can provide its user with the enjoyment of seeing the movement component and add the aesthetics, luxury and wristwatch decoration. Therefore, the movement component made of diamond crystal can add more luxury and decoration to the wristwatch.

[0068] Besides the movement component, by manufacturing an external component which is visible from outside, such as the protective cover, made of diamond crystal, more luxury and decoration can be added to the wristwatch. Additionally, by making an outer component with the wristwatch component according to the present disclosure, the outer component, although made of diamond, can be made more resistant to impact forces applied from outside the wristwatch. and prevent splitting, splitting, crazing, chipping and chipping. This should therefore promote the practical use of diamond crystals in wristwatches.

[0069] An explanation of the manufacturing method of the wristwatch component 1 is given below. First, a diamond crystal is prepared as shown in Fig. 8. The diamond crystal shown in Fig. 8 is the basic material of the wristwatch component 1, the outer shape of which is that of a plate.

[0070] The plan shape of the diamond crystal can be either quadrilateral, as shown in Fig. 8, or circular, as shown in Fig. 9(a), or circular with an orientation flat, as shown in Fig. 9(b). The quadrilateral shape can be, for example, a square or a rectangle. By using a flat substrate as shown in Fig. 9 as a base material, it is possible to use a diamond crystal substrate which is originally intended to be used for semiconductors, as it is, as a base material. of the wristwatch component 1, thereby raising the productivity of the wristwatch component 1.

[0071] A diamond crystal having a side length of between 10.0 mm and 203.2 mm is prepared if the diamond crystal is of a quadrilateral shape, or a diamond crystal having a diameter ϕ of between 10, 16 mm and 203.2 mm if the diamond crystal is of a circular shape. In the case of a rectangular shape among the quadrilateral shapes, the length of the short side should be set at least 10.0 mm and less than that of the long side, and the upper limit of the long side should be set at 203.2 mm. By setting the length or diameter in such a numerical range, a large diamond crystal can be prepared as a base material for the wristwatch component 1, thereby making a large watch component 1. The thickness T of the diamond crystal should be a desired value composed of the thickness t of the wristwatch component 1 and the margin for polishing.

Diamond crystal can be made, for example, by homoepitaxial growth, in which a diamond crystal is grown on a diamond crystal base substrate. Other methods include using a sapphire or magnesium oxide (MgO) substrate as the base substrate, on which a diamond crystal is formed by hetero-epitaxial growth. Specific examples of growth methods include pulsed laser deposition (PLD: Pulsed Laser Deposition), as well as vapor phase deposition, such as chemical vapor deposition (CVD: Chemical Vapor Deposition) and CVD by microwave plasma. As a variant, the process described in the international publication WO2015/046294A1 (the process for manufacturing a diamond monocrystal by coalescence of the diamond monocrystals after having placed a core of diamond monocrystal at the ends of the columnar diamonds) can be used.

[0073] The prepared diamond crystal is then subjected to a step of cutting by continuous laser irradiation to form at least part of the outline by arranging the aforementioned circular 2 or elliptical 3 arcs in order to separate the wristwatch component 1 from the crystal diamond.

To perform the laser irradiation, either a diamond crystal is prepared in advance that does not exhibit any of the following problems: grain boundaries, black spots, crystalline defects, and zones of machining alteration; either a part of the diamond crystal is selected which does not exhibit any of the following: grain boundaries, black spots, crystalline defects, zones of machining alteration, before carrying out the laser irradiation so that the wristwatch component 1 be removed from this game.

[0075] When separating the wristwatch component 1 by laser, the laser irradiation is carried out at regular time intervals and the diamond crystal is slid along the contour of the wristwatch component 1 by means of a positioning table at regular intervals synchronized with the laser irradiation intervals to arrange and form a series of thin circular or elliptical arcs at intervals (pitch P1 or P2) along the contour. In detail, the drawing data is loaded into the CAD/CAE and the laser irradiation is performed along the contour line of the wristwatch component 1 according to the drawing data. Alternatively, the diamond crystal can be fixed and irradiated while moving the output side of the laser along the contour shape, so as to arrange and form circular arcs 2 or elliptical arcs 3 in succession with the aforementioned intervals.

[0076] Since, according to the present disclosure, all or at least part of the contour of the wristwatch component 1 is formed solely by the formation of circular arcs 2 or elliptical arcs 3, and that the component wristwatch is separated from the diamond crystal in the desired shape, the cutting interval should be set so that there is no gap between the circular 2 or elliptical 3 arcs. So it is tolerable that circular arcs 2 or elliptical arcs 3 partially overlap.

If the pitch (P1 or P2) is less than 330 μm, the pitch is too small and the number of laser strikes is excessive, which reduces the mass production of the wristwatch component 1 and is therefore not not desirable. On the other hand, if the pitch is greater than 420 μm, each circular arc 2 or each elliptical arc 3 is only formed apart and is not connected, so that it is impossible to separate the component from wristwatch from the diamond crystal, which is also undesirable.

[0078] Further, the crystal plane in the direction of the diamond crystal plane, which is the base material of the wristwatch component 1, is most preferably (100), since it is the crystal plane 4 of the component. of wrist watch 1.

The laser emission conditions according to this embodiment are as follows. In order to prevent thermal effects on the diamond crystal, it is better to use pulsed lasers, while regarding wavelengths, it is better to use shorter wavelengths, which exhibit higher absorption in the diamond crystal and also prevent thermal effects. Lasers that meet these characteristics include, for example, Nd:YAG lasers, while the lasers used must have a wavelength of 532 nm or 355 nm and an output power of several hundred mW to several W.

[0080] The wristwatch component 1 separated from the diamond crystal is then subjected to mechanical polishing and mirror polishing by CMP to complete the production of the wristwatch component 1. The thickness t of the wristwatch component bracelet 1 after mirror polishing should be between 0.3mm and 3.0mm. The surface roughness Ra appearing on the appearance, including the crystal plane 4, of the wristwatch component 1 after mirror polishing should be 0.1 µm or less.

[0081] If necessary, the tips of the projections 2a formed between the circular arcs 2 are polished using a plane grinder or the like to shape them into projections 2b having the flat points or into projections 2c having the rounded points, such as illustrated in Figures 4 and 5 or Figures 6 and 7. This is to prevent cracks, splits, chips and chips from occurring on the tips of the wristwatch component 1 when subjected to impact forces applied from the outside. The tips of the projections 3a formed between the elliptical arcs 3 can also be polished in the same way.

EXAMPLES OF IMPLEMENTATION OF THE INVENTION

Examples of implementation of the present invention will be described below, but the invention is not limited to these examples. Firstly, as a base material for a mechanical wristwatch movement component, two plates of colorless single-crystal diamond, of a square shape in plan with a side of 10 mm and a thickness of 0, were prepared. 6 mm by hetero-epitaxial growth using microwave plasma CVD. The orientation of the main face of each single crystal diamond plate was set to (100). Furthermore, each single crystal diamond slab was observed to have no crystal defects such as grain boundaries, black spots, dislocations, twins, or distortions, nor any of the following chippings, cracks, splits, cracks, chips, or machining alteration zones.

[0083] Each monocrystalline diamond plate was cut by continuous laser irradiation to form the outline of a wristwatch component by arranging circular arcs so that they overlap and separate the wristwatch component 1 having the outer shape shown in Figure 1 of each single crystal diamond plate as a movement component. An Nd:YAG laser was used, setting the wavelength to 355 nm and the output power to several watts as appropriate.

The wristwatch component 1 separated from each monocrystalline diamond plate was then subjected to mechanical polishing and mirror polishing by CMP to obtain the wristwatch component 1 with a thickness t of 0.5 mm. and a surface roughness of Ra of 0.1 µm.

FIG. 10 shows a large-scale SEM (Scanning Electron Microscope) image of part of the outline of a movement component for a mechanical wristwatch according to the present example implementation of the invention. Figure 11 also shows a large scale SEM image of part of the outline of a motion component according to another exemplary implementation. In Figures 10 and 11, the gray area represents wristwatch component 1 and the black area represents space. Figures 10 and 11 have confirmed that the outline of the wristwatch component 1 is formed by a series of continuously arranged circular arcs. The pitch between the circular arcs is about 357 µm in both figures 10 and 11.

[0086] An impact test confirmed that no cracks, splits, cracks, chips or chips occurred when the wristwatch component 1 was subjected to impact forces applied from outside.

LIST OF REFERENCE SIGNS

[0087] 1: Wristwatch component 2: Circular arc forming part of the contour of the wristwatch component 2a, 2b, 2c: Projection between the circular arcs 3: Elliptical arc forming part of the contour of the wristwatch component 3a : Protrusion between elliptical arcs 4: Crystalline plane, which is a finished surface of the wristwatch component L: Length of one side of diamond crystal P1: Pitch between circular arcs P2: Pitch between elliptical arcs t: Thickness of the wristwatch component T: Thickness of the diamond crystal ϕ: Diameter of the diamond crystal

Claims (11)

1. Wristwatch component (1) consisting of a diamond single crystal, having an outline of which at least a part is formed by circular (2) or elliptical (3) arcs arranged at a pitch (P1, P2) comprised between 330 µm and 420 µm. 2. Wristwatch component (1) according to claim 1, wherein the thickness (t) of said wristwatch component is between 0.3 mm and 3.0 mm. The wristwatch component (1) according to claim 1 or 2, wherein the surface roughness Ra of said wristwatch component is 0.1 µm or less. 4. Wristwatch component (1) according to any one of claims 1 to 3 which does not present any of the following problems: grain boundaries, black spots, crystalline defects, and zones of machining alteration. 5. Wristwatch (1) comprising the wristwatch component according to any one of claims 1 to 4. 6. Method of manufacturing a wristwatch component (1) comprising the following steps: preparing a diamond single crystal whose plan shape is quadrilateral, circular or circular with an orientation flat, said quadrilateral shape having a side length of 10.0 mm or more, said circular shape having a diameter of 10 .16mm or more; the laser cutting of said diamond single crystal to form at least part of its outline with circular (2) or elliptical (3) arcs arranged at a pitch (P1, P2) comprised between 330 µm and 420 µm, followed by the separation of said wristwatch component of said diamond single crystal; And polishing said wristwatch component separated from said diamond single crystal to thereby finish manufacturing the wristwatch component. 7. A method of manufacturing a wristwatch component (1) according to claim 6, wherein said side length is between 10.0 mm and 203.2 mm or said diameter is between 10.16 mm and 203.2mm. 8. A method of manufacturing a wristwatch component according to claim 6 or 7, wherein the thickness (t) of said wristwatch component after said polishing is between 0.3 mm and 3.0 mm. 9. A method of manufacturing a wristwatch component (1) according to any one of claims 6 to 8, wherein the surface roughness Ra of said wristwatch component after said polishing is 0.1 µm or less. 10. A method of manufacturing a wristwatch component (1) according to any one of claims 6 to 9, in which a single crystal of diamond is prepared which does not exhibit any of the following: grain boundaries, black spots, crystalline defects , or areas of machining alteration, or separating said wristwatch component from a portion of said diamond single crystal having none of the following problems: said grain boundaries, said black spots, said crystalline defects, or said areas machining alteration. 11. A method of manufacturing a wristwatch component (1) according to any one of claims 6 to 10, wherein the crystal plane (4) in the direction of the plane of said diamond single crystal is a (100) plane. .