WO2000057743A2

WO2000057743A2 - Setting of gemstones

Info

Publication number: WO2000057743A2
Application number: PCT/ZA2000/000048
Authority: WO
Inventors: Anthony John Bond; Robert James Bond
Original assignee: Laser Optronic Technologies (Proprietary) Limited
Priority date: 1999-03-26
Filing date: 2000-03-20
Publication date: 2000-10-05
Also published as: WO2000057743A3; AU3775500A

Abstract

A system for setting a gemstone in a hollow jewellery piece, comprises means for creating a metallic attachment region secured to a surface of the gemstone, and a bonding means for bonding the at least one metallic attachment region to a shell of the hollow jewellery piece. The metallic attachment region is created by metallizing a circumferential portion of the surface of the gemstone, and electrodepositing a layer of metal on the metallized portion of the surface of the gemstone. Alternatively, the metallic attachment region is created by providing a metallic rod of cross-section conforming to the profile of a circumferential portion of the gemstone, and forming the metallic rod to abut, along its length, the circumferential portion of the gemstone.

Description

SETTING OF GEMSTONES

FIELD OF THE INVENTION

This invention relates to the setting of gemstones and, in particular, to the setting of gemstones in hollow jewellery pieces. The invention relates to a system and to a method for setting gemstones in hollow jewellery pieces and to a jewellery piece having a gemstone set therein by means of the method.

BACKGROUND TO THE INVENTION

Gemstones are set in jewellery pieces by means of claws or by means of invisible settings, also known as "pavPrinter coder'e'" settings.

In the former class of setting, a gemstone is held in position in a jewellery piece by means of claws, or fingers, projecting from the jewellery piece, at least part-way over the gemstone to hold it securely in place. This type of setting is disadvantageous in that the claws detract from the visual appeal and the beauty of the gemstone.

In an effort to overcome this disadvantage, the latter class of setting is used. This is an invisible setting in which a gemstone is placed in a recess in the jewellery piece such that the girdle, or position of greatest cross-section, of the gemstone is just below the surface of the jewellery piece. The surface of the jewellery piece adjacent the gemstone is then worked over the girdle to cause the gemstone to be gripped securely as illustrated in Figure 1. Recently, invisible settings have been devised in which the gemstone is held in position on a jewellery piece by means of a co-operating outwardly directed projection on the jewellery piece, and a circumferential groove on the girdle of the gemstone, as indicated in Rgure 2. The projection and groove may extend around the entire circumference of the gemstone or may extend over a plurality of circumferential segments.

The latter two types of setting, whilst showing off the beauty of the gemstone to better effect than a claw setting, cannot be used to set the gemstone in an item of hollow jewellery due to the absence of sufficient metallic material in the hollow jewellery piece to effectively hold the gemstone in place.

As far as the applicant is aware, there does not exist a method of setting a gemstone in a piece of hollow jewellery.

OBJECT OF THE INVENTION

It is the object of this invention to provide a system and a method for setting gemstones in items of hollow jewellery, which will, at least partially, alleviate the abovementioned difficulties and disadvantages.

SUMMARY OF THE INVENTION

In accordance with this invention there is provided a method for setting a gemstone in a hollow jewellery piece, which includes the steps of: providing at least one metallic attachment region secured to a surface of the gemstone; and bonding the at least one attachment region to a shell of the hollow jewellery piece.

Further features of the invention provide for providing the at least one metallic attachment region by: metallizing at least a portion of the surface of the gemstone; and electrodepositing a layer of metal on the metallized portion of the surface of the gemstone, alternatively by: providing a metallic rod of cross-section conforming to the profile of at least a portion of the gemstone; and forming the metallic rod to abut, along its length, the said portion of the gemstone. Still further features of the invention provide for metallizing an at least part-circumferential portion of the surface of the gemstone, for metallizing a circumferential portion of the surface of the gemstone, for metallizing the circumferential portion of the gemstone located at its girdle, and for metallizing a groove cut into the surface of the gemstone and extending over the at least the part-circumferential portion of the surface thereof.

Yet further features of the invention provide for forming the metallic rod into the groove, for forming the metallic rod into the circumferential groove as a circumferential band, and for bonding the ends of the circumferential band together.

There is also provided for bonding the metallic rod along its length to the metallized portion of the gemstone, and for bonding the metallic rod to the metallized portion of the gemstone by spot welding.

There is further provided for the method to include the additional step of drawing the rod prior to forming, to have a cross-section conforming to the profile of the at least part-circumferential portion of the gemstone.

In accordance with a first aspect of the invention there is provided for the method to include the further steps of: providing a CAD model of the hollow jewellery piece; rapid prototyping a three-dimensional pattern of the hollow jewellery piece from the CAD model, the three-dimensional pattern having a recess adapted to accommodate the gemstone therein; placing the gemstone having the at least one metallic attachment region on the surface thereof, into the recess on the pattern; and electrodepositing a layer of metal on the surface of the three-dimensional pattern to form the shell of the hollow jewellery piece, with the shell being bonded to the at least one metallic attachment region on the surface of the gemstone.

There is also provided for rapid prototyping the three-dimensional pattern of the hollow jewellery piece from the CAD model by any one of the techniques of stereo lithography, fused deposition modelling, laminated object manufacturing, selective laser sintering, or other rapid prototyping systems. ln accordance with a second aspect of the invention there is provided for the method to include the further steps of: providing a CAD model of the hollow jewellery piece; deriving from the CAD model forming tools for forming a number of metallic component parts from which the hollow jewellery piece is to be assembled; forming the metallic component parts, at least one component part having an aperture therethrough adapted to accommodate the gemstone therein; assembling the number of formed metallic component parts to form the shell of the hollow jewellery piece; placing the gemstone having the at least one metallic attachment region on the surface thereof, into the aperture on the shell of the hollow jewellery piece; and bonding the gemstone to the hollow jewellery piece by welding the at least one metallic attachment region on the surface of the gemstone to the shell of the hollow jewellery piece.

There is further provided for welding the at least one metallic attachment region on the surface of the gemstone to the shell of the hollow jewellery piece by means of a multi-axis welding robot.

The invention extends to a system for setting a gemstone in a hollow jewellery piece, comprising: means for providing at least one metallic attachment region secured to a surface of the gemstone; and bonding means for bonding the at least one attachment region to a shell of the hollow jewellery piece.

Further features of the invention provide for the means for providing the at least one metallic attachment region to include: metallizing means for metallizing at least a portion of the surface of the gemstone; and an electrodeposition facility for electrodepositing a layer of metal on the metallized portion of the surface of the gemstone, alternatively, means for providing a metallic rod of cross-section conforming to the profile of at least a portion of the gemstone; and forming means for forming the metallic rod to abut, along its length, the said portion of the gemstone. Still further features of the invention provide for the metallizing means to metallize an at least part-circumferential portion of the surface of the gemstone, for the metallizing means to metallize a circumferential portion on the surface of the gemstone, for the circumferential portion on the surface of the gemstone to be located at its girdle, for the system to include a cutting facility for cutting a groove into the surface of the gemstone extending over the at least part-circumferential portion of the surface to be metallized, and for the cutting facility to be a laser cutting machine.

Yet further features of the invention provide for the forming means to form the metallic rod into the groove, for the forming to form the metallic rod into the circumferential groove as a circumferential band, and for the bonding means to bond the ends of the circumferential band together.

In accordance with a first aspect of the invention there is provided for the for the system to include: means for producing a CAD model of the hollow jewellery piece; a rapid prototyping facility arranged to produce, from the CAD model, a three-dimensional pattern of the hollow jewellery piece, the three-dimensional pattern having a recess adapted to accommodate the gemstone therein; and a handling facility for placing the gemstone having the metallic attachment region into the recess on the three-dimensional pattern.

There is further provided for the bonding means to be the electrodeposition facility which is arranged to eiectrodeposit a layer of metal on the surface of the three-dimensional pattern to form a shell of the hollow jewellery piece with the shell being bonded to the at least one metallic attachment region on the surface of the gemstone.

There is still further provided for the rapid prototyping facility to produce the three-dimensional pattern of the hollow jewellery piece from the CAD model by any one of the techniques of stereo lithography, fused deposition modelling, laminated object manufacturing, selective laser sintering, or other rapid prototyping systems.

In accordance with a second aspect of the invention there is provided for the system to include: means for producing a CAD model of the hollow jewellery piece; means for producing, from the CAD model, forming tools for forming a number of metallic component parts from which the hollow jewellery piece is to be assembled; forming means for forming the component parts of the hollow jewellery piece by utilizing the forming tools, at least one component part having an aperture therethrough adapted to accommodate the gemstone therein; an assembly facility for assembling the formed component parts together to produce the hollow jewellery piece; and a handling facility for placing the gemstone having the metallic attachment region into the aperture in the hollow jewellery piece.

There is yet further provided for the bonding facility to be a laser welding robot for welding the metallic attachment region on the gemstone to the shell of the hollow jewellery piece.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described below, by way of example only, and with reference to the accompanying drawings, in which:

FIG. 1 is a sectional view of a gemstone set in a jewellery piece by means of a prior art pave' setting;

FIG. 2 is a sectional view of a gemstone set in a jewellery piece by means of an alternative prior art pave' setting;

FIG. 3 is a sectional view of a first embodiment of a gemstone with a circumferential band, according to the invention;

FIG. 4 is a sectional view of a second embodiment of a gemstone with a circumferential band, according to the invention;

FIG. 5 is a flow diagram of the steps involved in a first method for setting a gemstone in an item of hollow jewellery, according to the invention; and

FIG.6 is a flow diagram of the steps involved in a second method for setting a gemstone in an item of hollow jewellery, according to the invention DETAILED DESCRIPTION OF THE INVENTION

Referring to Figures 3 to 5 in which like features of the invention are indicated by like numerals, a system for mounting a gemstone into an item of hollow jewellery is indicated generally by reference numeral (1).

Several systems are known for manufacturing hollow jewellery pieces. Although, in the description which follows, particular mention will be made to hollow jewellery pieces manufactured in accordance with two systems and methods for manufacturing hollow jewellery pieces which are disclosed in applicant's South

African Patent Application No. ??????, it is to be clearly understood that the invention extends to the mounting of gemstones into hollow jewellery pieces manufactured in accordance with other methods.

The system (1) includes a cutting facility in the form of a laser cutting machine (2), an electroforming bath (3), a production facility (4) for producing hollow jewellery pieces, and a bonding facility (5), which will be described in greater detail below.

The laser cutting machine (2), well known in the art and is commonly applied to cut and round diamonds, this latter operation also being known as "bruting".

A gemstone (6) which is to be mounted in a hollow jewellery piece (not shown) is placed in a universally movable jig (not shown) under the laser of the laser cutting machine (2) and a circumferential groove (7) is cut into the surface of the gemstone around the girdle thereof. The groove (7) is then metallized at (8) by the application of a silver solution or a silver spray thereto and the partially metallized gemstone is placed in the electroforming bath (3) containing a gold potassium cyanide solution. An electrical current is then applied between the metallized groove (7) of the gemstone (6), and a cathode electrode (not shown) immersed in the electroforming bath, to cause electrodeposition of gold in the circumferential groove (7). The electrodeposition is continued until a sufficiently thick circumferential band of gold (9) has been deposited in the circumferential groove (7) on the gemstone (6), as indicated in detail in Figure 3.

In the first method for manufacturing a hollow jewellery in the production facility

(4), a three dimensional pattern (not shown) of a desired hollow jewellery piece (not shown) is produced from a three-dimensional CAD model of the jewellery piece by means of a rapid prototyping facility in the form of a Stereo Lithography (SL) machine. The operation of the rapid prototyping facility is well known in the art and will not be described here in detail.

In order to mount the gemstone (6) into the hollow jewellery piece, a cavity is formed in the pattern during the stereo lithography process to accommodate the gemstone therein such that the electroformed circumferential gold band on the gemstone protrudes just above the surface of the three-dimensional pattern.

The surface of three-dimensional pattern (not shown) is then metallized in the manner described above, secured to a support structure also known as a "tree", and then immersed in the bonding facility (5) in the form of the electroforming bath (3). Gold is then electrodeposited in a conventional manner on the surface of the metallized three-dimensional pattern until a sufficiently thick layer of gold has been deposited on the surface of the pattern to form the shell of the hollow jewellery piece according to the requirements of a particular application.

It will be appreciated by those skilled in the art that the layer of gold electrodeposited on the surface of the three-dimensional pattern (not shown) will bond with the circumferential gold band on the gemstone (6), thus holding the gemstone securely in place in the hollow jewellery piece.

In the second method for manufacturing a hollow jewellery piece in the production facility (4), matching punches and dies are produced to form the component parts of a hollow jewellery piece by means of a stamping operation.

The stamped component parts of the hollow jewellery piece are then placed in a jig (not shown) to hold the parts together in a correct configuration to form the item of hollow jewellery. The jig is then brought into position under the bonding facility (5) in the form of a multi-axis laser welding robot and the component parts of the hollow jewellery piece are laser-welded together.

Where a gemstone (6) is to be mounted in the hollow jewellery piece, a suitably-sized aperture is stamped into a relevant component part at the forming stage thereof. The aperture is sized such that when the gemstone (6) is placed therein, the circumferential gold band on the gemstone abuts the periphery of the aperture. The assembled hollow jewellery piece is placed in a jig under the laser of the multi-axis welding robot (5). The circumferentially-banded gemstone is carried by a robot handling system and placed in position in the aperture on the shell of the hollow jewellery piece. The assembly comprising the hollow jewellery piece and the gemstone is then moved under the laser of the welding robot where the circumferential gold band is laser-welded to the periphery of the aperture of the hollow jewellery piece.

Numerous modifications are possible to this first embodiment without departing from the scope of the invention. In particular the circumferential groove and the electrodeposited metallic band may be circumferentially discontinuous and comprise a plurality of circumferential segments. Further, the necessity for a circumferential groove on the gemstone can be eliminated by metallizing the circumference of the gemstone at its girdle, and electrodepositing the gold band directly thereon, as indicated in Figure 4. Still further, the three-dimensional pattern of the hollow jewellery piece can be rapid-prototyped by any one of the techniques of Fused Deposition Modelling, Laminated Object Manufacturing, Selective Laser Sintering, or other rapid prototyping systems as alternatives to Stereo Lithography.

In the alternative embodiment of the invention illustrated in Figure 6, a system (1) for setting a gemstone in a hollow jewellery piece comprises a cutting facility in the form of a laser cutting machine (2) metallizing means (3) for metallizing any desired portion of the surface of the gemstone, a drawing means (4) arranged to draw a metallic rod down to a desired cross-section, and a bonding facility (5) which will be described in greater detail below.

A gemstone (6), which is to be mounted in a hollow jewellery piece, is placed in a universally movable jig (not shown) under the laser cutting machine (2), and a circumferential groove (7) is cut into the surface of the gemstone around the girdle thereof. The groove (7) is then metallized by the metallizing means (3) by application of a silver solution or a silver spray thereto. A metallic rod is drawn down by the drawing means (4) to a shape having a cross-section conforming substantially to the profile of the metallized portion of the gemstone (6). The drawn metallic rod is then formed in the metallized groove on the gemstone and is bonded to the metallized surface of the gemstone by spot-welding by means of the bonding facility (5) in the form of a laser welding machine. ln order to set the gemstone (6) in a hollow jewellery piece, the banded gemstone is placed in a suitably-sized aperture in the hollow jewellery piece such that, when the gemstone is placed therein, the metallic rod bonded to the gemstone abuts the periphery of the aperture. The assembly comprising the hollow jewellery piece and the gemstone is then moved under the laser of the laser welding machine (5), where the circumferential metallic rod is laser-welded to the periphery of the aperture of the hollow jewellery piece.

It will be appreciated by those skilled in the art that this method eliminates the step of electrodepositing a circumferential gold band in the groove of the gemstone, as is described in the first embodiment of the invention, thereby shortening the production time required to set a gemstone in an item of hollow jewellery.

Numerous modifications are possible to this alternative embodiment without departing from the scope of the invention. In particular, the circumferential groove and the metallic rod may be circumferentially discontinuous and comprise a plurality of circumferential segments. Further, the necessity for a circumferential groove on the gemstone can be eliminated by metallizing the circumference of the gemstone at its girdle, and bonding the appropriately drawn metallic rod directly thereto as illustrated in Figure 4. Still further, the metallizing step may be eliminated altogether by forming the metallic rod into the circumferential groove and joining its ends together by means of spot welding.

It will be appreciated by those skilled in the art that the methods described above enable a gemstone to be securely mounted in an item of hollow jewellery, without detracting from the aesthetic beauty of the gemstone. Further, the methods are applicable to the mounting of all types of gemstones, including diamonds and other precious and semi-precious stones.

The invention therefore provides a rapid, simple and secure way of setting gemstones in items of hollow jewellery.

Claims

1. A method for setting a gemstone in a hollow jewellery piece, which includes the steps of: providing at least one metallic attachment region secured to a surface of the gemstone; and bonding the at least one attachment region to a shell of the hollow jewellery piece.

2. A method as claimed in claim 1 in which the at least one metallic attachment region is provided by the steps of: metallizing at least a portion of the surface of the gemstone; and electrodepositing a layer of metal on the metallized portion of the surface of the gemstone.

3. A method as claimed in claim 1 in which the at least one metallic attachment region is provided by the steps of: providing a metallic rod of cross-section conforming to the profile of at least a portion of the gemstone; and forming the metallic rod to abut, along its length, the said portion of the gemstone.

4. A method as claimed in claim 2 in which an at least part- circumferential portion of the surface of the gemstone is metallized.

A method as claimed in claim 4 in which a circumferential portion of the surface of the gemstone is metallized.

6. A method as claimed in claim 5 in which the circumferential portion of the surface of the gemstone which is metallized is located at its girdle.

7. A method as claimed in any one of claims 4 to 6 in which the at least part-circumferential portion of the gemstone which is metallized is a groove cut into the surface of the gemstone.

8. A method as claimed in claim 7 in which the metallic rod is formed into the groove.

9. A method as claimed in claim 8 in which the the metallic rod is formed into the circumferential groove as a circumferential band.

10. A method as claimed in claim 9 in which the ends of the circumferential band are bonded together.

11. A method as claimed in any one of claims 3 to 10 in which the metallic rod is bonded along its length to the metallized portion of the gemstone.

12. A method as claimed in claim 11 in which the metallic rod is bonded to the metallized portion of the gemstone by spot welding.

13. A method as claimed in claim 12 which includes the additional step of drawing the rod, prior to forming thereof, to have a cross-section conforming to the profile of the at least part-circumferential portion of the gemstone.

14. A method as claimed in any one of the preceding claims includes the further steps of: providing a CAD model of the hollow jewellery piece; rapid prototyping a three-dimensional pattern of the hollow jewellery piece from the CAD model, the three-dimensional pattern having a recess adapted to accommodate the gemstone therein; placing the gemstone having the at least one metallic attachment region on the surface thereof, into the recess on the pattern; and electrodepositing a layer of metal on the surface of the three-dimensional pattern to form the shell of the hollow jewellery piece, with the shell being bonded to the at least one metallic attachment region on the surface of the gemstone.

15. A method as claimed in claim 14 in which the three-dimensional pattern of the hollow jewellery piece is rapid-prototyped from the CAD model by any one of the techniques of stereo lithography, fused deposition modelling, laminated object manufacturing, selective laser sintering, or other rapid prototyping systems.

16. A method as claimed in any one of claims 1 to 13 which includes the further steps of: providing a CAD model of the hollow jewellery piece; deriving from the CAD model forming tools for forming a number of metallic component parts from which the hollow jewellery piece is to be assembled; forming the metallic component parts, at least one component part having an aperture therethrough adapted to accommodate the gemstone therein; assembling the number of formed metallic component parts to form the shell of the hollow jewellery piece; placing the gemstone having the at least one metallic attachment region on the surface thereof, into the aperture on the shell of the hollow jewellery piece; and bonding the gemstone to the hollow jewellery piece by welding the at least one metallic attachment region on the surface of the gemstone to the shell of the hollow jewellery piece.

17. A method as claimed in claim 16 in which the at least one metallic attachment region on the surface of the gemstone is welded to the shell of the hollow jewellery piece by means of a multi-axis welding robot.

18. A system for setting a gemstone in a hollow jewellery piece, comprising: means for providing at least one metallic attachment region secured to a surface of the gemstone; and bonding means for bonding the at least one attachment region to a shell of the hollow jewellery piece.

19. A system as claimed in claim 18 in which the means for providing the at least one metallic attachment region includes: metallizing means for metallizing at least a portion of the surface of the gemstone; and an electrodeposition facility for electrodepositing a layer of metal on the metallized portion of the surface of the gemstone.

20. A system as claimed in claim 18 in which the means for providing the at least one metallic attachment region includes: means for providing a metallic rod of cross-section conforming to the profile of at least a portion of the gemstone; and forming means for forming the metallic rod to abut, along its length, the said portion of the gemstone.

21. A system as claimed in claim 19 in which the metallizing means metallizes an at least part-circumferential portion of the surface of the gemstone.

22. A system as claimed in claim 21 in which the metallizing means metallizes a circumferential portion of the gemstone.

23. A system as claimed in claim 22 in which the circumferential portion on the surface of the gemstone is located at its girdle.

24. A system as claimed in any one of claims 21 to 23 which includes a cutting facility for cutting a groove into the surface of the gemstone extending over the at least part-circumferential portion of the surface to be metallized.

25. A system as claimed in claim 24 in which the cutting facility is a laser cutting machine.

26. A system as claimed in either one of claims 24 or 25 in which the forming means forms the metallic rod into the groove.

27. A system as claimed in claim 26 in which the forming means forms the metallic rod into the circumferential groove as a circumferential band.

28. A system as claimed in claim 27 in which the bonding means bonds the ends of the circumferential band together.

29. A system as claimed in any one of claims 18 to 28 which includes: means for producing a CAD model of the hollow jewellery piece; a rapid prototyping facility arranged to produce, from the CAD model, a three-dimensional pattern of the hollow jewellery piece, the three-dimensional pattern having a recess adapted to accommodate the gemstone therein; and a handling facility for placing the gemstone having the metallic attachment region into the recess on the three-dimensional pattern.

30. A system as claimed in claim 29 in which the bonding means is the electrodeposition facility which is arranged to electrodeposit a layer of metal on the surface of the three-dimensional pattern to form a shell of the hollow jewellery piece, with the shell being bonded to the at least one metallic attachment region on the surface of the gemstone.

31. A system as claimed in either one of claims 29 or 30 in which the rapid prototyping facility produces the three-dimensional pattern of the hollow jewellery piece from the CAD model by any one of the techniques of stereo lithography, fused deposition modelling, laminated object manufacturing, selective laser sintering, or other rapid prototyping systems.

32. A system as claimed in any one of claims 18 to 28 which includes: means for producing a CAD model of the hollow jewellery piece; means for producing, from the CAD model, forming tools for forming a number of metallic component parts from which the hollow jewellery piece is to be assembled; forming means for forming the component parts of the hollow jewellery piece by utilizing the forming tools, at least one component part having an aperture therethrough adapted to accommodate the gemstone therein; an assembly facility for assembling the formed component parts together to produce the hollow jewellery piece; and a handling facility for placing the gemstone having the metallic attachment region into the aperture in the hollow jewellery piece.

33. A system as claimed in claim 32 in which the bonding facility is a laser welding robot for welding the metallic attachment region on the gemstone to the shell of the hollow jewellery piece.

34. A method for setting a gemstone in a hollow jewellery piece, substantially as herein described with reference to Figures 3,4 and 5, or Figures 3,4 and 6.

35. A system for setting a gemstone in a hollow jewellery piece, substantially as herein described with reference to and as illustrated in Figures 3,4 and 5, or Figures 3,4 and 6.