Patent Application
20170135450
The disclosed technology relates generally to a brazed attachment of gemstones to themselves and/or a metallic mount.
Currently, gemstones are held in place by one or more mechanical methods. Prongs and channel set are two examples that are commonly used. Gemstones are clamped or retained to maintain position within the setting. Rings, tiaras, bracelets, broaches, earrings, studs and necklaces all employ a retention mechanism to keep gemstones attached. Bonding may also be used but due to the properties associated with bonding the reliability makes this method less desirable. Soldering is typically done as a metal to metal joint. Other methods exist that employ wire wrapping or other forms of containment but not direct chemical bond to the gemstone. Compression is also employed in a tension mount which contains the gemstone without a bond.
The disclosed technology relates generally to a gemstone setting comprising: a gemstone; at least one mounting surface; and at least one braze joint, the at least one braze joint being formed from a reactive metallic braze alloy, the braze joint adhering the gemstone to the mounting surface, the braze joint being substantially concealed from a direct line of sight from a top portion of the gemstone by preventing excessive alloy from extending beyond a desired braze area near the girdle region, whereby a vastly more secure mount is provided where each individual joint fully retains the stone.
In some implementations, the mounting surface is a surface of a hollow mounting rod and excess alloy is prevented from extending beyond the desired braze area by delivering the reactive metallic alloy to the desired braze area through the hollow mounting rod or excess alloy is prevented from extending beyond the desired braze area by inserting the reactive metallic alloy inside the hollow mounting rod, constraining the reactive metallic braze alloy within a controlled volume inside the hollow mounting rod, and thermal brazing a delivered amount of the reactive metallic alloy. The brazed hollow mounting tube can be attached to the gemstone setting.
In some implementations, the mounting surface is a surface of a second gemstone and excess alloy is prevented from extending beyond the desired braze area by positioning a foil, a preform or a paste (applied with a syringe) containing the reactive metallic alloy, such as, Incusil ABA by Wesgo Metals, on the desired braze area. The gemstone can be retained via pressure against a table of the gemstone and the desired braze area with the reactive metallic alloy being placed between the desired braze area and the mounting surface.
In some implementations, the mounting surface is a surface of the gemstone setting and excess alloy is prevented from extending beyond the desired braze area by positioning a foil, a rod, a wire, a paste or a powder containing the reactive metallic alloy on the desired braze area or excess alloy is prevented from extending beyond the desired braze area by positioning a rod containing the reactive metallic braze alloy on the desired braze area or excess alloy is prevented from extending beyond the desired braze area by surrounding the desired braze area with a braze stopoff material, such as, “STOPYT”™ Morgan Advanced Ceramics.
In some implementations, the braze joint can be substantially concealed from a direct line of sight from a top portion of the gemstone by positioning the braze joint on or near a girdle or a surface of the gemstone or the braze joint is substantially concealed from a direct line of sight from a top portion of the gemstone by inherent internal reflection and surface refraction of the gemstone.
In another implementation, a gemstone arrangement can comprise: at least three gemstones, each gemstone being brazed to at least two gemstones on separate and non-parallel planes at a braze point wherein the at least three gemstones are princess-cut gemstones and the braze point is formed on a girdle of the princess-cut gemstones.
Other advantages of brazing include a jewelry setting that is less prone to catching on clothing, having fewer small voids for collecting dirt and are easier to maintain in general.
This specification describes technologies relating to a brazed joint for attachment of gemstones to each other and/or a metallic mount. More specifically, using a controlled atmosphere of inert gas or a vacuum, a braze joint can be formed to join diamonds, sapphires and/or other gemstones to each other or a mounting feature or a jewelry mounting. (The term “gemstone” can refer to any stone used in jewelry including natural or manufactured stones, e.g. cubic zirconium). This attachment forms a durable foundation that doesn't conceal the stone but allows for a unique design that relies on contact away from the crown region. Contact may also be made anywhere desired for all types of configurations or cuts depending on desired geometry.
Brazing is used to attach diamond material to oil well bits and industrial saw blades. In these applications, a paste or matrix with alloy encapsulates the diamond material and obscures most of the diamond material allowing some edges of the stone to be on a surface of the matrix for cutting purposes.
Traditional jewelry settings for gemstones have mounting means fixedly positioning the gemstone to the setting. As shown in
The brilliance of the diamond results from its very bright and smooth surface for reflection in combination with its high refractive index. Diamonds are cut in a manner such that when a viewer is looking at the crown/table, the light entering the diamond through the table/crown is reflected within the diamond by the pavilion's facets and exits through facets on the crown or the table for the benefit of the viewer. Fire describes the ability of the diamond to act as a prism and disperse white light into its colors. Fire is evaluated by the intensity and variety of color.
Referring now to
Other losses occur based on how the gemstone is mounted on a jewelry setting, e.g., gemstones held in place by prongs block light from entering and leaving the gemstone or gemstones held in place in an invisible setting where grooves are cut into the pavilion create permanent and irreparable imperfections in the gemstone. Losses occur because these mounting techniques block or alter the surface of the diamond from natural light thereby lowering the brilliance and fire of the gemstone and also altering a gemstone's color.
This specification describes technologies relating to a brazed joint for attachment of gemstones to themselves and/or a metallic mount. Brazing occurs above 450 C, soldering is below 450 C. Brazing is a metal-joining process whereby a filler metal is heated above melting point and distributed between two or more close-fitting parts by direct contact and capillary action. The filler metal is brought slightly above its melting (liquidus) temperature while protected by a suitable atmosphere. It then flows over the base metal (known as wetting) and is then cooled to join the workpieces together. In another implementation, a gold braze alloy can be used that does not go into a liquidous temperature but instead the braze can be heated to a point where diffusion bonding occurs instead of brazing.
In order for a brazing technique to be applied in a jewelry setting for gemstones, a limited amount of alloy is used in regions of the gemstone which minimize alloy needed and lowers obscurations. That is, instead of merely capturing the gemstone, the braze technique of the disclosed technology provides directly attaching the gemstone to, e.g., another gemstone, a jewelry setting or an attachment rod in a manner that is aesthetically pleasing and adds to the brilliance, fire and scintillation of the gemstone while minimizing color change. The attachment point on the gemstone can be anywhere on the diamond, for example, in some implementations the attachment point can be on the girdle, on the pavilion near the girdle or, or on the crown near the girdle. Furthermore, it can be advantageous to braze to flat surfaces in between facets instead of on angles thereby avoiding failures due to lower strength crystal structure at these points. A properly placed braze joint creates a desired braze area that is concealed from view from the front of the gem by surface refraction and internal reflection, and hence does not materially affect its brilliance, fire, scintillation or color. The optical efficiency loss for a round brilliant cut in a four prong mount is more than four times greater than for the brazed joint design. This translates into increased brilliance and prevents color loss with the single point brazed joint design.
Other important factors to consider when using a braze joint in a jewelry setting is to (1) have tight temperature control during brazing, (2) have a coefficient of thermal expansion compatibility of materials, (3) good mechanical joint fit at the proper location on the gemstone, and (4) a proper metal alloy to promote active braze alloys (ABA) joint formation. In order to obtain high-quality brazed joints, the gemstones and the attachment point must be closely fitted. In most cases, joint clearances of 0.02 to 0.06 mm are recommended for the best capillary action and joint strength and direct contact is preferred.
The braze used in the disclosed technology creates an interface layer that reacts with both gemstone and metal attachment or another gemstone. It is important to control, limit and/or restrict the braze alloy in a butt joint to prevent excessive alloy from getting outside the desired braze area. The desired braze area size depends on the application. In one implementation, using an 18 gauge or 1 mm diameter joint gives a load carrying capability of between approximately 10 to 25 lbs. strength. It is worthy to note that the joint size is a function of the area so strength drops off as the square of the radius, meaning that smaller joints may be possible if strength is adequate for the application, as shown in the table below. Also, larger stones do not require much larger joints than smaller carat stones.
When determining gage, some factors to be considered are: (1) the proportion of the gage to the stone to be set, (2) strength of the joint when torsion is applied, (3) number of braze joints, e.g., double points can be used to increase strength, (4) configuration of attachment point, e.g., v-shaped attachments can provide greater strength, and (5) providing a smaller section for the attachment to act as a weaker point that yields prior to overstressing a joint, e.g., a small rod made out of precious metal.
The techniques described in the disclosed technology can control the amount of alloy in a braze joint by utilizing, e.g., a tube delivery system, a rod with a braze foil attached, placement of a stop material around a desired joint area and/or using an alloy foil or wire in a controlled manner (e.g., an array of small dots), to name a few. The amount of braze must be restricted otherwise, the braze can be seen through a top portion (crown/table) of the diamond thereby effecting its brilliance, fire and scintillation. Another issue with excess alloy is that a large amount of excess may cause fracturing of the gemstone where excess droplets form.
In one implementation, as shown in
This delivery method provides improved flow and increased braze alloy volume without excessive joint growth. In use, the tube 100 may be stainless steel but other tube materials can be used, e.g., Niobium, Titanium, Platinum, Stainless Steel and non-zinc gold alloy (as zinc in 14 k gold is not compatible with vacuum braze). The use of Niobium and Titanium has a more favorable chemistry for brazing and are also much less expensive than using platinum or gold.
In some implementations, in order to “wet” diamonds and sapphires, braze alloys typically have to be “activated.” This activation is usually done with Titanium or Zirconium. The filler metals that are activated are called “ABA” alloys (Active Braze Alloys), and they are very sensitive to oxidation. In order to not oxidize the alloys (which ruins them), the brazing process can be run in a very hard vacuum, e.g., vacuum levels of 10-4 and 10-5 Torr Range. However, any element in the vacuum that has a “high vapor pressure”, will be vaporized in the furnace. This vaporization causes two negative results: 1) it changes the braze alloy composition, and thus its melt temperature and metallurgical characteristics and 2) it contaminates the furnace and the thermocouples. Zinc, Lead, Cadmium and Tin are the most common elements that tend to vaporize. In practice, most alloys, e.g. gold, used in the jewelry industry contain zinc or tin which is not suitable for vacuum furnace brazing. Therefore, alloys that do not contain zinc or tin are contemplated.
In some implementations, the alloy 102 can be any silver based ABA braze alloy because the ABA braze alloy has the proper chemistry to braze to both the gemstone and the metallic member. The composition percentages of one of the braze alloys can be, e.g. 63.0% Ag 35.25% Cu, 1.75% Ti. Also, the reaction layer and braze joint of ABA alloys is much thinner than other adhesives and is easily concealed while providing an extremely strong attachment. Other active braze alloys, such as, 68.8% Ag, 26.7% Cu, 4.5% Ti can also be used as well as any alloy for effectively brazing gemstones.
In another implementation, as shown in
In another implementation, as shown in
As shown in
In some implementations, a face bond “butt joint” geometry is used to enable mounting to any face desired. As shown in
In
In
The brazing process can be performed in a vacuum furnace. A vacuum furnace is a type of furnace that can heat materials, typically metals, to very high temperatures, such as, 600 to over 1500° C. to carry out processes such as brazing, sintering and heat treatment with high consistency and low contamination. In a vacuum furnace the product in the furnace is surrounded by a vacuum. The absence of air or other gases prevents heat transfer with the product through convection and removes a source of contamination. Some of the benefits of a vacuum furnace are: uniform temperatures in the range around 700 to 1000° C., temperature can be controlled within a small area, low contamination of the product by carbon, oxygen and other gases, quick cooling (quenching) of product. The process can be computer controlled to ensure metallurgical repeatability. Other brazing techniques are contemplated, e.g., induction brazing, laser brazing or any other method that may work in an inert environment.
One example of the brazing process is as follows. (1) Prepare a gemstone by rinsing with acetone. (2) Inspect the surface of gemstone where braze joint is desired to ensure cleanliness. (3) Prepare a metallic setting rod/tube by rinsing with the rod/tube with acetone. (4) Inspect a brazing surface of the mount to ensure cleanliness. (5) Check proper joint geometry with respect to gemstone mounting location. (6) Clean, cut and apply braze alloy foil to rod braze face, or clean cut and load braze alloy wire into tube, flush (or near flush) with braze face. (7) Load alloyed rod/tube into brazing fixture and secure in place. (8) Load gemstone into brazing fixture (9) Position and secure gemstone such that the braze alloy and joint interface are positioned per the prescribed location on the gemstone. (10) Adjust rod/tube to match braze face angles and tighten securely. (11) Place assembled brazing tool in Vacuum furnace and attach thermocouples to assembly or tool, and (12) Program and braze the assembly per the desired thermal parameters as described below.
In some implementations, the steps or parameters of the brazing procedure in a vacuum furnace are as follows: (1) the assembled brazing tool is placed into an all Moly Vacuum Furnace, (2) pump furnace down to 5×10-5 Torr or better, (3) heat to 500 F+/−100 F at 1500 F/hr for 15-20 minutes, (4) heat to 1000 F+1-50 F at 1500 F/hr for 15-20 minutes, (5) heat to 1390 F+/−15 F at 1500 F/hr for 20-30 minutes, (6) heat to 1530 F-1550 F at 1800 F/hr for 12-18 minutes, (7) vacuum Cool to below 1200 F, (8) argon cool to below 250 F, (9) remove and dissemble the brazing tool. Please note that these parameters apply to Cusil ABA (Wesgo Metals™) chemistry being 63% Ag, 35.25% Cu, and 1.75% Ti.
In some implementations, a brazing tool, shown in
In another implementation, it is contemplated to cast using lower temperatures for brazing. The braze joint may be visible and create color changes but for small stones it may not matter.
In some implementations, the braze alloy can contain titanium. This titanium which reacts with the ceramic to form a reaction layer. In use, the more the titanium used, the higher the braze temperature needed. In other implementations, a low temperature alloy is used. In either case, the chemical bonding that occurs provides a resilient mounting which can be attached to either a universal mount or directly to jewelry mounting. Joints made using braze techniques are strong and durable.
It is contemplated to use dissolvable ceramic fixtures for pave settings. For example, using dissolvable tooling to make pave settings with attachment of stones to each other In other words, a complex matrix can be made out of a dissolvable mold that makes the finished jewelry look unsupported. These molds can be made with a 3d printer in almost any conceivable shape, inserting the braze alloy and gemstones during the printing process.
It is also contemplated to process multiple stones in a single furnace braze operation to reduce cost.
In another implementation, a region of the alloy that touches a gemstone can be doped with a reactive element, e.g., Ti, instead of having the reactive element being present in the alloy itself. This process is beneficial when there is a very limited attachment region needed at the gemstone-to-metal interface. It can be also possible to simplify the brazing process by adding the reactive element at a surface of an attachment rod, e.g., dipping, depositing or applying a small amount of the reactive element to the end of the attachment rod.
In another implementation, as shown in
In another implementation, the brazing application of an alloy is done in a controlled manner in such a way that that the alloy can be brazed without having to add a Nicrobraze glue. This is advantageous because during exposure to high temperatures the glue has potential to deposit a coating, black spots or both on the stone that require cleaning. Without the glue, less labor is needed to clean the braze area or risk potential damage to gemstone.
In another implementation, the braze application can include a laser heating method to set the braze area. The laser heating system can also include an automated system that operates on a conveyor belt in an inert gas to braze multiple gemstone within a limited time period.
In another implementation, the braze application can use an alloy that has materials needed for a reactive layer between individual stones, e.g., the alloy can be made of materials that could be chemically strengthened or removed or assimilated, e.g., a diamond dust mixed with Ti or some other material could be applied to a small area for a superior braze.
In another implementation, a diamond prong can be set in a metal setting and used a braze point.
In another implementation, the gemstone can become an integral part of the structure thereby allowing the brazing of several gemstones to each other as well as to rods. The gemstone therefore may become the connection instead of just a “trapped” stone. Care must be given so that if a large lever is created by the setting it can magnify applied loads into the stone and can cause excessive forces on the joint that can cause failure.
In another implementation, the attachment of the braze joint setting is into a piece of jewelry. It is different than anything else in terms of the use of a separate rod attachment applied to a direct attachment or hidden attachment to the rest of the jewelry. The use of non-standard settings with treaded or riveted or removable stones using a locking mechanism on the rod are contemplated.
In another implementation, as shown in
In another implementation, as shown in
While this specification contains many specific implementation details, these should not be construed as limitations on the scope of the disclosed technology or of what can be claimed, but rather as descriptions of features specific to particular implementations of the disclosed technology. Certain features that are described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable sub combination. Moreover, although features can be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination can be directed to a sub combination or variation of a subcombination.
The foregoing Detailed Description is to be understood as being in every respect illustrative, but not restrictive, and the scope of the disclosed technology disclosed herein is not to be determined from the Detailed Description, but rather from the claims as interpreted according to the full breadth permitted by the patent laws. It is to be understood that the implementations shown and described herein are only illustrative of the principles of the disclosed technology and that various modifications can be implemented without departing from the scope and spirit of the disclosed technology.
This application is a continuation-in-part of U.S. patent application Ser. No. 15/021,422, filed Mar. 11, 2016, now pending, which is a 371 National Stage Entry of PCT/IB2013/002350, filed Aug. 20, 2013, which was based on U.S. patent application Ser. No. 13/971,440, filed Aug. 20, 2013, now U.S. Pat. No. 9,204,693, issued Dec. 8, 2015, which claims benefit of U.S. Provisional Patent No. 61/692,245, filed Aug. 20, 2012. The patent applications identified above are incorporated here by reference in its entirety to provide continuity of disclosure.
| Number | Date | Country | |
|---|---|---|---|
| 61691245 | Aug 2012 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 13971440 | Aug 2013 | US |
| Child | 15021422 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15021422 | Mar 2016 | US |
| Child | 15341541 | US |
