This invention relates to a method for casting or molding an article of jewelry, and more particularly, to a method for producing a bored out or hollow jewelry article such as a ring.
There are many well known processes used in the large volume production of jewelry. Such processes include die striking, casting and electroforming, all of which are used for producing metallic jewelry articles. Such production methods are capable of facilitating high volume, high speed production with very good reproducibility. For example, using permanent-mold casting or injection molding techniques, a single mold cavity may be used repeatedly to produce, at a low cost, a virtually unlimited number of jewelry articles of intricate detail and varying size.
In order to reduce production costs in the manufacture of jewelry articles, previous improvements have generally focused upon-better equipment; very little effort has been directed to actually modifying the jewelry article that is produced in order to reduce the cost thereof. One way, of course, of reducing production costs is to reduce the amount of precious or semi-precious metal that is used in producing a jewelry article, while still achieving the visual presentation that is desired by the jewelry designer.
One such prior method involves the use of an acid or water-soluble wax insert disposed in a mold cavity in order to form a mold of a partially or completely hollow article. According to this technique, a soluble wax core insert is placed in a mold cavity. Then a molten wax is injected into the mold cavity, filling the cavity and surrounding the core insert. The core insert is then removed in order to produce a wax article having a hollow core.
In the prior art, the use of soluble wax core inserts has been less than desirable. In the first place, there have been difficulties in achieving proper alignment of the insert and in preventing random movement or shifting of the insert during waxing or casting. In addition, the prior art has failed to teach the use of a soluble wax core insert such that a hollow or bored out space is defined within the ring which extends virtually along the entire arcuate length thereof.
Moreover, in the prior art U.S. Pat. No. 5,718,278 to Baum, it is stated that it is not possible to produce a ring having an inner round radius design utilizing a vertically oriented mold configuration. However, the Baum process which utilizes a horizontally oriented mold configuration is less than desirable since it is not able to produce a ring which is hollowed or bored out to an arcuate content of 200° and up to or approaching 360°.
In the prior art patents to Hashimian et al, U.S. Pat. Nos. 6,453,699 and 6,554,052 there is taught a method for fabricating a hollow jewelry article which is bored out to an arcuate extent of 200° or greater.
Generally speaking, in accordance with the invention, there is provided a method or process for fabricating a hollow jewelry article which is hollowed or bored out. In accordance with this process, a metal ring model is prepared comprising a solid shank and a metal plate supported along the internal perimeter of the shank having a plurality of spokes extending to the shank. A first metal mold is produced from the metal ring model having the external shape of the jewelry article to be manufactured. From this mold, a wax model of the jewelry article is produced which is first filed down and then cast in order to form a metal model of a core insert; the core insert, like the ring model, has a plate disposed along the perimeter of the shank and a plurality of extending spokes. This core insert is used to produce a second metal mold. This second mold may then be used repeatedly in order to form a soluble wax core insert model which is then inserted into the cavity of the first mold in order to define the hollow region of the article. A non-soluble wax is then introduced into the first mold for completely surrounding the soluble wax core insert. The non-soluble wax then hardens and the entire unit is removed from the first mold, including the soluble wax core. The core is then removed by a suitable water soluble or chemical mechanism. The remaining wax model contains a hollow core running along a substantial portion of the arcuate length thereof. The wax model is then cast in order to form the inventive ring design.
Because the ring model includes a plate with extending spokes supported along the internal perimeter of the shank, it is possible to produce a core insert of a similar configuration, thereby enabling the production of a ring or other jewelry article which is bored out or hollowed within the shank thereof.
It is therefore an object of the invention to produce a ring design having a shank which is hollowed.
Another object is to produce a ring design which uses less metal but still exhibits the same physical appearance.
Yet a further object of the invention is to produce a ring design in which the inside surface of the shank is substantially flat with rounded or beveled edges.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.
The invention accordingly comprises the several steps and the relation of one or more of such steps with respect to each of the others thereof, as well as an article of manufacture produced by carrying out these steps, and which possesses the features, properties and relation of elements, all of which will be exemplified in the process and article hereinafter disclosed and described, and the scope of the invention will be indicated in the claims.
For a fuller understanding of the invention, reference is made to the following description taken in connection with the accompanying drawings, in which:
Referring first to
Referring now to
To facilitate proper alignment and assembly of die elements 23 and 25, locator pins 33 are provided along die element 25 for fitting into corresponding locator holes 35 formed along die element 23. Die elements 23 and 25 also define an inlet port 22 of mold 11 for injecting wax thereinto, as later described.
As shown in
Each of side inserts 27 and 29 are cylindrically shaped and include inwardly directed top surfaces 28A and outside radial surfaces 28B and 30B. Top inside surface 28A of side insert 27 is formed with locator buttons 65 and a locator foot 67 for selectively and cooperatively engaging the top inside surface of side insert 29. Because of their design, side inserts 27 and 29, when mated together, define a space or cavity 26 (see
Once mold 21 is fully assembled, wax is injected therein through inlet port 22 in order to produce a wax model of the ring. The wax model is filed down, after which it is cast in order to produce a metal core insert model 81, as depicted in
Core insert mold 91, used to form a core insert, as described below, is of a somewhat similar construction to that of ring mold 11 and includes a first metal die element 93, a second metal die element 95, and a pair of side mold inserts 94A and 94B, which together, when assembled, define a core cavity 96. Die element 95 includes a pair of locator pins 98 which are designed to be matingly engaged with locator holes 100, as indicated in
Core insert wax model 111 is produced following injection of soluble wax or other suitable soluble material through port 106 and into core insert mold 91 (
To fabricate the inventive ring extending fingers 115, core insert wax model 111 is placed inside ring mold 21, as shown in
Once core insert wax model 111 is precisely positioned within ring mold 21, mold 21 is closed and a molten wax is introduced through port 22 and into ring mold 21 (see
Non-soluble component 121 is used to produce a cast metal ring generally indicated at 131 in
Ring 131 is formed with upper openings 139a and 139c and lower openings 139b and 139c along finger facing surface 134 of shank 133 leading to an internal running hollow cavity 138 (see
Cavity 138 arcuately extends between 240° and 300° along shank 133. In this embodiment, finger facing surface 134 is flat with beveled edges 149. Significantly, in order to enhance comfort when wearing ring 131, shank 133 (see
Importantly, wall 132 of shank 133 has a thickness of between 0.017 and 0.030 inch. The preferred thickness of wall 132 is 0.020–0.22 inch.
In accordance with the invention, each opening of ring 131 produced under the current invention has an arcuate range of between about 15° to 30° and are three-five in number.
In the three opening version of the inventive ring, as shown in
Ring 161 shown in
In the five opening version of the inventive ring, as shown in
It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained by practicing the invention and it is also understood the invention includes any and all changes or modifications thereto which would be apparent to one of ordinary skill in the art and which come within the spirit and scope of the inventive concept.
Number | Name | Date | Kind |
---|---|---|---|
5718278 | Baum | Feb 1998 | A |
6453699 | Hashimian et al. | Sep 2002 | B1 |
6467526 | Cope | Oct 2002 | B1 |
6554052 | Hashimian et al. | Apr 2003 | B1 |
Number | Date | Country | |
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20060090870 A1 | May 2006 | US |