CH714307A2 - Method of crimping a stone - Google Patents

Abstract

The invention relates to a method of assembling a stone (1) on a fixing support (2), said stone (1) being cut to present a table, a crown, a rondiste (5) and a cylinder head , said assembly method comprising the following steps: a) providing a substrate (8) comprising at least one housing (10) in which said stone (1) is positioned, said housing (10) being arranged to form between the substrate (8) and said stone (1) a peripheral free space (12) at least at the level of the girdle (5) and zones (4a, 6a) of the crown (4) and the yoke (6) contiguous with the a girdle (5), said peripheral free space (12) comprising a bottom (14) having a conductive surface (16); b) electrically depositing in said peripheral free space (12) a metal layer (36) at least at the level of (5) and zones (4a, 6a) of the crown (4) and the bolt (6) adjoining the girdle (5) so as to imprison forming said rounder (5) in said metal layer (36) to form, at least substantially around the girdle (5) of the stone (1), said fixing support (2) c) releasing said stone (1) and its support fixing (2) the substrate (8). The invention also relates to a crimping method on an element of a timepiece or jewelery of a stone and its fixing support obtained according to said assembly method.

Description

Description

FIELD OF THE INVENTION [0001] The invention relates to a method of assembling a stone on a fixing support, said stone being cut to present a table, a crown, a rondiste and a cylinder head. The invention also relates to a crimping method on an element of a timepiece or jewelery of a stone and its fixing support obtained according to said assembly method.

BACKGROUND OF THE INVENTION [0002] It is known to crimp precious, semi-precious or synthetic stones using claws, grains or rails. The traditional crimping by mounting a natural stone, such as diamond or emerald, in a kitten with claws generally imposes a dimensional control of the size of stones close to 5/100. Therefore, this type of crimping is not compatible with that of stones set with large series at low cost using stones of a greater accuracy, close to 1/100, such as synthetic diamond, zircon and ruby. SUMMARY OF THE INVENTION The object of the present invention is to overcome this disadvantage by proposing a method of crimping stones that makes it possible to overcome the inevitable dimensional variations encountered when natural stones, such as diamonds or emeralds, are used.

For this purpose, the invention relates first of all to a method of assembling a stone on a support, said stone being cut to present a table, a crown, a round and a cylinder head, said method comprising the following steps: a) providing itself with a substrate comprising at least one housing in which said stone is positioned, said housing being arranged to form between the substrate and said stone a peripheral free space at least at the level of the the stone and zones of the crown and the breech contiguous to the girdle, the bottom of said peripheral free space having a conductive surface; b) depositing galvanically in said peripheral free space a metal layer at least at the level of the girdle and the zones of the crown and the breech contiguous to the rondist so as to trap said rondist in said metal layer to form, at least substantially around the ron said rock, said fixing bracket c) releasing said stone and its support for fixing the substrate.

In a particularly advantageous manner, the substrate and its housing can be made according to the following steps: d) providing a substrate having a conductive layer on the surface and producing in said substrate at least one through hole e) covering the substrate of a photosensitive resin layer, and photolitographically form in the photosensitive resin a cavity of dimensions, in the plane of the substrate, greater than the dimensions of the rondiste of the stone, so that the cavity comprises a central opening in correspondence with the through hole and a peripheral zone comprising resin side walls and a bottom occupied by the conductive layer of the substrate around the through hole, the dimensions of the cavity and the through hole forming the housing being selected so that the stone head is partially lodged in the through hole to rest on the periphery of the central opening of the cavity the remainder of the breech above the through-hole defining the breech area adjacent to the girdle, and such that the remainder of the stone between the breech area adjacent to the girdle and at least to the level of the girdle the crown contiguous to the rondiste is lodged in the cavity so as to form between the stone and the walls of the cavity, said peripheral free space.

The method of the invention allows to choose the dimensions of the housing, and more particularly the dimensions of the through hole, so as to adapt to the dimensional variations of the stones.

The invention also relates to a method of crimping a stone on an element of a timepiece or jewelery including the mounting of the stone and its fixing support obtained according to the method as defined above on a kitten then reported on the timepiece element or jewelry or directly on the timepiece element or jewelry.

The invention also relates to a timepiece or jewelery element comprising at least one stone assembled on its fixing support obtained by the assembly method as defined above.

BRIEF DESCRIPTION OF THE DRAWINGS [0009] Other particularities and advantages will become clear from the following description, given by way of indication and in no way limitative, with reference to the appended drawings, in which: FIGS. 1 to 6 are representations of the successive steps of a method of assembling a stone on a fixing support according to the invention; figs. 7a to 7c are top views of different stone shape variants and fixing brackets obtained according to the method of the invention; and FIG. 8 is a sectional view showing a stone and its mounting bracket mounted on a kitten.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0010] Referring to FIGS. 1 to 6 and 8, the present invention relates to a method of assembling a stone 1 on a fixing support 2, said stone 1 being cut to present a table 3, a crown 4, a rondiste 5 and a cylinder head 6. Such a stone is preferably a stone of natural origin, such as diamond or emerald, whose dimensions may vary from one stone to another. It is obvious that the stone can be of any other nature, natural or synthetic, the method according to the invention can also be advantageously used for such stones.

The first step a) of the method of assembling the stone 1 on a fixing support 2 according to the invention consists in providing a substrate 8 comprising at least one housing 10 in which said stone 1 is positioned, said housing 10 being arranged to form between the substrate 8 and said stone 1 a peripheral free space 12 at least around the rounder 5 of the stone 1, the bottom 14 of said peripheral free space 12 having a conductive surface 16. "Around the rounder" means that the peripheral clearance 12 is at least at the level of the girdle 5 and of the zones 4a and 6a of the crown 4 and the yoke 6 respectively contiguous to the girdle 5.

More specifically, the substrate 8 and its housing 10 may advantageously be made according to the following steps d) and e): Step d) consists in providing a substrate 8 having a conductive layer 16 in surface and to achieve in said substrate 8 at least one through hole 18. A through hole 18 is formed by stone 1 to be assembled. Advantageously, the substrate 8 is for example based on silicon, glass, ceramic, or quartz. For example, silicon wafers for microelectronics may be used. The conductive layer 16 may be obtained for example by PVD deposition (Physical Vapor Deposition) of chromium, titanium, gold and their combinations. Any other suitable conductive layer may be used. The through holes 18 may be formed on the substrate 8, for example by laser ablation. Advantageously, the distribution of the through holes 18 on the surface of the substrate is optimized in particular according to the dimensions of the housing, the shape of the fixing brackets, etc., in order to have a maximum number of through holes on the surface of the substrate. substrate surface 8.

Step e) consists in covering the substrate 8 with a layer of photoresist 20 as shown in FIG. 1, then to form by photolithography in said photosensitive resin 20 a cavity 22, said cavity 22 and the through hole 18 forming the housing 10 in which will be positioned the stone 1 as will be described below. The cavity 22 is hollowed out until the conductive layer 16 appears.

The dimensions of the through hole 18, in the plane of the substrate 8, are of dimensions smaller than the dimensions (generally called "diameter") of the rounder 5 of the stone 1 and the dimensions of the cavity 22, in the plane of the substrate 8, are greater than the diameter of the rondiste 5 of the stone 1. Consequently, the cavity 22 has dimensions, in the plane of the substrate8, greater than the dimensions of the through hole 18, the cavity 22 then comprising a central opening 24 in correspondence with the through hole 18, and a peripheral zone comprising resin side walls 26 and a bottom, that is to say the bottom 14 occupied by the conductive layer 16 of the substrates around the through hole 18. The housing 10 therefore has a T-shaped section in the plane perpendicular to the substrate 8, as shown in FIG. 2.

In a particularly advantageous manner, step e) comprises the use of a negative photoresist, for example an SU8 resin, the UV irradiation of the photoresist layer 20 through a corresponding mask. to the contour of the desired fixation support, and the removal of the non-irradiated portion of the photoresist layer 20 so as to obtain the cavity 22 whose contour corresponds to the contour of said desired fixation support. Such a photolithographic method is known per se to those skilled in the art and does not require a more detailed description. Once the substrate 8 and its housing 10 made, step a) of the assembly method according to the invention continues with the establishment of a stone 1 in each of the housing 10 formed.

The dimensions of the cavity 22 and the through hole 18 forming the housing 10 are chosen so that the cylinder head 6 of the stone 1 is partially housed in the through hole 18 to rest on the periphery of the central opening 24 of the cavity 22, the remainder of the yoke 6 above the through hole 18 defining the zone 6a of the yoke 6 adjacent to the girdle 5, and so that the remainder of the stone 1 between said zone 6a of the yoke 6 contiguous with the 5 and at least to the level of the zone 4a of the crown 4 adjacent to the girdle 5 is housed in the cavity 22 so as to form between the stone 1 and the walls of the cavity 22, that is to say the side walls 26 and the bottom 14, said peripheral free space 12. [0019] In a particularly preferred manner, the dimensions of the cavity 22 and the through hole 18 are chosen so that the cylinder head 6 of the stone 1 is housed almost entirely in the through hole 18 so that the breech zone 6a 6 contiguous to the girdle 5 extends only immediately below the girdle 5, and the zone 4a of the crown 4 contiguous to the girdle 5 extends only immediately above the girdle 5 so as to form between the stone 1 and the walls of the cavity 22, that is to say the side walls 26 and the bottom 14, said peripheral free space 12 only substantially around the girdle 5, that is to say at the 5 and only immediately on either side of said rounder 5, as shown in FIG. 3. In addition, the housing 10, and more particularly the cavity 22, has a height such that the table 3 of the stone 1 protrudes from said housing 10, and more particularly from the cavity 22, as shown in FIG. 3. The thickness of the resin layer 20 is chosen for this purpose.

The only precise dimension of the stone can be assured being the "diameter" of the rounder 5 and height, it is possible that the establishment of the stone 1 is not done properly, and does not allow to ensure sufficient flatness of the table 3 of the stone 1.

In this case, the assembly method according to the invention may comprise, between steps a) and b), a step f) for correcting the orientation of the stone. Advantageously, and with reference to FIG. 4, this step f) may comprise contacting the table 3 of the stone 1 with a repositioning device 28 arranged to reposition the stone 1 in its housing 10. Such a repositioning device 28 comprises for example a rigid plate 30 covered with a deformable carpet or a foam 32 to compensate for the heights of the stones 1. The repositioning device 28 is arranged so that the carpet or the foam 32 is brought into contact with the tables 3 stones positioned in their homes respectively on the substrate 8 so as to correct the orientation of said stones and to ensure the flatness of the tables 3 of the stones 1.

Before removing the repositioning device 28, it may be necessary to provide, between steps f) and b), a stage g) fixing the cylinder head 6 of the stone 1 in the through hole 18. This step g) makes it possible to maintain the correct positioning of the stones 1 in their housings 10, even after the repositioning device 28 has been removed. [0023] The stage g) consists, for example, of introducing, through the free inlet of the through hole 18, a retaining glue 34 around the cylinder head 6 of the stone 1 for fixing the stone 1 in the housing 10. In order to prevent the retaining glue 34 from passing into the cavity 22 in case of play between the stone 1 and the central opening 24 can be used a sufficiently viscous retaining adhesive that will not fill the finest interstices. It is also possible to close, on the side of the cavity 22, the interstices existing between the stone 1 and the central opening 24, prior to the deposition of the retaining glue 34. For this purpose, it is possible to spray into said interstices, next to the cavity 22, a resin that can easily be removed (by dissolution for example). It is also possible to provide a deposition of an indium layer of approximately 50 μm on the silicon substrate 8 before the setting of the stones 1. The indium layer has the advantage of being deformed during the step f) of correcting the orientation of the stones by leveling the tables 3 and then being able to seal at the central opening 24 of the cavity 22.

The stage g) is followed by a step h) of removal of the repositioning device 28 to continue the implementation of the assembly process of the invention.

Once the stone 1 positioned in its housing 10 on the substrate 8 by forming between said substrate 8 and said stone 1 a peripheral free space 12 at least at the level of the girdle 5 and the zones 4a and 6a respectively of the crown 4 and the cylinder head 6 contiguous to the girdle 5 according to step a) described above, the assembly method according to the invention continues with the implementation of step b). This step b) consists in depositing by galvanic means in said peripheral free space 12, from the bottom 14 of said peripheral free space 12 occupied by the conductive layer 16, a metal layer 36 at the level of the girdle 5 and the zones 4a, 6a respectively the crown 4 and the cylinder head 6 contiguous to the girdle 5, so as to trap said girdle 5 in said metal layer 36 to form, at least substantially around the girdle 5 of the stone 1, said support 2, as shown fig. 6. Since its rondist 5 is trapped in the metal layer 36 constituting the fixing support 2, the stone 1 is now secured to its fixing support 2.

The metal layer 36 deposited in step b) is preferably made of a material selected from the group consisting of nickel, gold, silver, platinum, rhodium, palladium, copper and their alloys. alloy.

The electroforming conditions, in particular the composition of the baths, the geometry of the system, the voltages and current densities, are chosen for each metal or alloy to be electro-deposited according to the techniques well known in the art of the art. electroforming (see for example Di Bari GA "electroforming" Electroplating Engineering Handbook 4th Edition written by LJ Durney, published by Van Nostrand Reinhold Company Inc., NY USA 1984).

Claims (13)

claims 1. A method of assembling a stone (1) on a fixing support (2), said stone (1) being cut to present a table (3), a crown (4), a rondiste (5) and a cylinder head (6), said assembly method comprising the following steps: a) providing a substrate (8) comprising at least one housing (10) in which said stone (1) is positioned, said housing (10) being arranged to form between the substrate (8) and said stone (1) a peripheral free space (12) at least at the level of the girdle (5) and zones (4a, 6a) of the crown (4) and the yoke ( 6) contiguous to the girdle (5), said peripheral free space (12) comprising a bottom (14) having a conductive surface (16) b) electrically depositing in said peripheral free space (12) a metal layer (36) at less at the level of the girdle (5) and the zones (4a, 6a) of the crown (4) and the yoke (6) contiguous with the girdle (5) so as to imprison the said rondi ste (5) in said metal layer (36) to form said fixing support (2) c) releasing said stone (1) and its attachment support (2) from the substrate (8). 2. Method according to claim 1, wherein the substrate (8) and its housing (10) are made according to the following steps: d) provide a substrate (8) having a conductive layer (16) surface and achieve in said substrate (8) at least one through-hole (18) e) covering the substrate (8) with a photoresist layer (20), and forming photolithographically in the photoresist (20) a cavity (22) of dimensions, in the plane of the substrate (8), greater than the dimensions of the girdle (5) of the stone (1), so that the cavity (22) comprises a central opening (24) in correspondence with the through hole (18) and a peripheral zone comprising resin side walls (26) and a bottom (14) occupied by the conductive layer (16) of the substrate around the through hole (18), the dimensions of the cavity (22) and the through hole ( 18) forming said housing (10) being chosen so that the yoke (6) of the stone (1) is accommodated by in the through hole (18) to rest on the periphery of the central opening (24) of the cavity (22), the remainder of the yoke (6) above the through-hole (18) defining the area (6a). ) of the breech (6) contiguous to the girdle (5), and so that the remainder of the stone (1) between said zone (6a) of the breech (6) contiguous with the girdle (5) and at least until level of the zone (4a) of the ring (4) contiguous to the girdle (5) is housed in the cavity (22) so as to form between the stone (1) and the walls (26, 14) of the cavity (22). ), said peripheral free space (12). 3. Method according to claim 2, characterized in that the dimensions of the cavity (22) and the through hole (18) are chosen so that the yoke (6) of the stone (1) is housed substantially entirely in the hole through (18) so that the area (6a) of the breech (6) contiguous to the girdle (5) extends only immediately under the girdle (5), and the zone (4a) of the crown (4) abuts the girdle (5) extends only immediately above the girdle (5) so as to form between the stone (1) and the walls (26, 14) of the cavity (22), substantially at the level of the girdle (5) and said zones (4a, 6a) of the crown (4) and the yoke (6) contiguous to the girdle (5), said peripheral free space (12). 4. Method according to one of the preceding claims, characterized in that the housing (10) has a height such that the table (3) of the stone (1) protrudes from said housing (10). 5. Method according to claim 4, characterized in that it comprises, between steps a) and b), a step f) for correcting the orientation of the stone (1). 6. Method according to claim 5, characterized in that step f) comprises contacting the table (3) of the stone (1) with a device (28) for repositioning the stone (1) in its housing (10). 7. Method according to claim 5 or 6, characterized in that it comprises, between steps f) and b), a stage g) for fixing the yoke (6) of the stone (1) in the through-hole ( 18). 8. Method according to claims 6 and 7, characterized in that the stage g) is followed by a step h) of removal of the device (28) repositioning. 9. Method according to one of the preceding claims, characterized in that the metal layer (36) deposited in step b) is made of a material selected from the group consisting of nickel, gold, silver, nickel, platinum, rhodium, palladium, copper and their alloys. 10. Process according to claim 2, characterized in that step e) comprises the use of a negative photoresist (20), the UV irradiation of the photoresist layer (20) through a corresponding mask. to the contour of the desired fixing support (2), and removing the non-irradiated part of the photosensitive resin layer (20) so as to obtain said cavity (22) whose contour corresponds to the contour of the fixing support (2) ). 11. Method according to one of the preceding claims, characterized in that the substrate (8) is based on a material selected from the group comprising silicon, a ceramic, a glass and a quartz. 12. Method of crimping a stone (1) on an element of a timepiece or jewelery including the mounting of the stone (1) and its fixing support (2) obtained by the assembly method according to claims 1 to 11 on a kitten (38) attached to the timepiece element or jewelry or directly on the timepiece element or jewelry. 13. Timepiece or jewelery element comprising at least one stone (1) assembled on its fixing support (2) obtained by the assembly method according to claims 1 to 11.