US1000470A - Ring-mold. - Google Patents

Description

F. 0. WIDMANN.

RING MOLD.

APPLICATION FILED FEB. 11, 1908.

Patented Aug. 15,1911.

[dz/E 221271- I DOLI-IMBIA PLANOGRAPH CIL, WASHINGTON, D. C.

FRANK O. WIDMANN, OF CLEVELAND, OHIO.

RING-MOLD.

Specification of Letters Patent.

Patented Au 15, 1911.

Application filed February 11, 1908. Serial No. 415,340.

To all whom it may concern:

Be it known that I, FRANK C. WIDMANN, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Ring-Molds, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

This invention relates to molds such as used by jewelers for casting rings. In my Patent No. 844,072 issued February 12th, 1907, there is shown a mold for this purpose which comprises two mold sections, each of which is made of iron, with an integral central core of similar material which is adapted to be assembled with said sections to produce a complete mold. This mold has proven satisfactory and efficient in operation, provided that the mold is heated before pouring the molten gold thereinto. It will not work satisfactorily, however, unless so heated prior to the pouring of the molten gold thereinto, the gold refusing to flow readily on the cold iron surfaces of the mold. Furthermore, the iron has to be specially prepared to prevent the adherence of gold thereto even after it has been heated,such special preparation consisting generally in burning the iron with horsehoof.

The object of this invention is to provide a mold whereinto the gold may be poured without the necessity for preheating the mold and without liability to crack the band or produce cavities therein.

A further object of the invention is to accomplish the above results in a mold which is simple of construction and cheap of production.

I accomplish these objects by the embodiment of my invent-ion illustrated in the drawings forming part hereof, wherein Figure 1 represents a perspective view of the complete mold, showing the same opened up with the center and head cores in place; Fig. 2 represents a side elevation of the assembled mold; Fig. 3 represents an elevation of one of the mold sections with the cores'in place, the center core being represented in section; and Fig, 4 represents an enlarged sectional view of the head core and of the adjacent portions of the ring.

Describing the parts by reference characters, 1 and 2 denote the body portions or sections of the mold. These sect-ions may be formed as rectangular blocks, and each is provided with a central aperture 3 extending therethrough. Surrounding the central aperture, in each block is an incomplete or fractional annular groove 4, whereby, when said sections are assembled, a complete mold groove is provided for the body or band of the ring. Each fractional groove may be provided with a suitable number of fractional vents 5 formed in the inner faces of the sections 1 and 2 and extending to the sides thereof, placing the mold groove in. communication with the atmosphere. Four such vent passages are shown, the fractional passages in one member matching or registering with those in the other whereby, when the sections are assembled, four complete vent passages are provided, extending from the mold groove to the outside of the mold. Two of these vent passages communicate with the upper, portion of the ring mold groove and extend thence upwardly to the outer surface of the mold, and the remaining two communicate wit-h the lower portion of the ring mold groove and extend downwardly to the exterior of the mold.

Mold section 2 is provided with dowel pins 6 and section 1 with holes 7 so located as to cause the sections to be assembled with the groove sections 1 and vent passages in the two sections in direct opposition to each other. Each section 1 and 2 is provided with a fractional inlet groove 9 communicating with its fractional mold groove, said inlet grooves forming, when the sections are assembled, a hopper-like inlet for pouring the molten gold into the mold. Each section 1 and 2 is also provided in the lower portion thereof with a fractional groove 11 extending from the lower surface of the section to the lower portion of the fractional ring mold groove. These grooves are of such shape that, when the sections are as sembleol, a passageway is provided which is adapted to receive and closely surround the core 12 by which the ring head is formed. To secure the parts of the mold together, each section is provided with a hook 18 and a stud 14, whereby the parts may be held in operative relation during the operation of casting.

Core 12 is preferably an integral body having a stem 15 adapted to project beyond the lower portion of the mold and a contracted body portion 16, the lower portion of which is substantially cylindrical and the upper portion of which is preferably frustoconical. The frusto-conical surface is provided with grooves 18, said grooves diminishing in cross-sectional area from top to bottom thereof to form correspondingly shaped claws or arms for the setting. The lower end of each of these grooves communicates with a vent passage 19 extending the length of the contracted cylindrical portion 16 of the core and communicating with the exterior of the mold. The provision of the vent grooves 5 and 18 contributes to the formation of a perfect casting, which result is further facilitated by other features of the mold to be discussed hereinafter. The core 12 is supported within the mold by means of a pin 20 extending through an aperture in the core and through corresponding apertures 21 in the core sections.

For the material of which the mold sections are composed, I employ a metal to which the molten gold will not adhere when said metal is cold. I have found aluminum to be particularly well suited for this purpose, as it requires no special preparation, such as has been mentioned in connection with iron molds. In attempting to make rings by pouring the molten gold into a cold aluminum mold constructed with a central integral core within each groove 4, it has been found that the contraction of the gold in cooling against the solid core thus provided causes the band to break, generally at two portions located on opposite sides of the inlet groove 9. To overcome this objection, I provide a central core 22 of material which will not resist the contraction of the gold in cooling to such extent as to fracture the band. I have found cuttlefish and charcoal to be admirably adapted for this purpose, as they are porous and are charred or burned by the molten gold sufficiently to accommodate the contraction thereof in cooling, at the same time forming a firm support for the inner surface of the band. It frequently happens, however, that bands thus produced have cavities on the inner faces thereof adjacent to the core. To prevent the formation of such cavities, I provide the core 22 with ports so arranged as to distribute some of the molten gold directly to the i te i of e groove 1:. For t is pur pose, I provide the core 22 with a vertical port 23 extending from the upper surface substantially to the center thereof, where it merges with a pair of downwardly inclined ports 24 and 25 leading to opposite portions of the groove 4 and discharging into said groove at points substantially equidistant from the inlet port. I have found that good results are obtained by making the diameters of these ports equal to about one-half or onethird of the width of the groove 4:. To centor the core 22 properly with reference to the groove and to the inlet port 9, I provide the core 12 with a pin 26, which not only extends through the ring groove to form the opening through the body of the ring hehind the setting but extends into a corresponding opening 27 in core 22, said opening being arranged substantially midway between the outlet ends of ports 24 and 25, and said recess and ports 23, 24 and 25 being in the same plane. The pin 26 is preferably made of steel or iron; for, should it be formed of aluminum (as is the case with core 12), it would be melted by the molten gold.

It will be observed that the upper ends of the mold sections are provided respectively with plates 28 and 29 which are secured thereto and are provided each with a fractional aperture constituting the inlet through which molten metal is introduced into the port 9. These plates are preferably of steel and are secured to the aluminum body beneath by means of screws 30. The purpose of these plates is to protect the aluminum of which the mold body is composed from being melted by the contact therewith of the crucible from which the molten gold is introduced into the mold. The length of time that the crucible usually rests upon the top of the mold in pouring will be suflicient to melt the. aluminum body molds, and the plates 28 and 29 prevent this action.

Before assembling the parts, I apply lycopodium powder to the central core 22 and to the inner faces of the mold sections and apply oil to the core 12.

By the construction described, I have produced a mold which is simple of construction, cheap of production, but which will enable substantially perfect rings to be cast without the necessity for heating the mold body, and which can be used repeatedly without deterioration,the only part subject to renewal being the core 22. As this core may be made of charcoal, the cost of renewal is practically negligible.

Having thus described my invention, I claim:

1. A ring mold comprising a pair of sections of aluminum each having therein a fractional groove, means for securing said sections together, a core cooperating with the ring groove and formed of a material which will accommodate the contraction of the gold in cooling, said core having ports for receiving molten metal and distributing the same to various parts of the mold groove.

2. A ring mold comprising a body of metal to which molten gold will not adhere when said metal is unheated, said body having a mold groove therein, and a core within said groove, said core being formed of material which will accommodate the contraction of the gold in cooling and having ports for receiving molten gold and distributing the same to the interior of the mold groove.

3. A ring mold having an inlet port and comprising a pair of sections made of metal to which molten gold will not adhere when said metal is unheated, said sections having each a fractional mold groove therein and a core removably fitted within said groove, said core consisting of a body having therein a vertical port adapted to communicate with the inlet port of the mold and provided with lateral ports communicating with said vertical port and extending through said core to opposite portions of the mold groove.

4. A ring mold comprising a pair of sym metrical sections made of metal to which molten gold will not adhere when said metal is unheated, each section having therein a fractional inlet port and a fractional mold groove, a core located within said groove, said core consisting of a body having therein a vertical port adapted to communicate with the inlet port of the mold and with downwardly extending lateral ports communicating with said vertical port and extending through said core to opposite portions of the mold groove.

5. In a ring mold, the combination of a body having an inlet port and having therein a mold groove for the body or band of the ring and a transverse aperture within said groove, a core removably fitted in said aperture and having a port adapted to com municate with the inlet port of the body and one or more distributing port-s leading from the former port to the mold groove, and a core removably fitted in said body and having a centering projection adapted to engage the former core.

6. In a ring mold, the combination, with a body having therein a mold groove for the body or band of the ring and an inlet port extending into said groove, a transverse aperture within said groove and a second aperture for the reception of the ring-head core, of a core fitted in the former aperture and having a receiving port adapted to communicate with the inlet port and with distributing ports extending from the former port and also having a recess intermediate between the discharge ends of the distributing ports, and a ring-head core having a projection adapted to extend into the aperture in the former core and thereby center the same.

7. In a ring mold, the combination of a pair of sections each having a fractional mold groove therein and a fractional inlet port communicating with its fractional groove, each section having a groove for the reception of the ring-head core and a transverse aperture within the mold groove, a core in said transverse aperture provided with a port adapted to communicate with the inlet port and with branch distributing ports extending from the receiving port through opposite portions of the core, and a ring-head core in the groove therefor, the latter core being provided with means for centering the former core.

8. In a ring mold, the combination of an aluminum body having therein a mold groove and an inlet port communicating with said groove, said body being provided with an aperture extending transversely of and located within the mold groove, and a core of material, as charcoal, in said aperture, said core having an inlet port adapted to communicate with the inlet port of the body and with one or more distributing ports communicating with the mold groove.

9. In a ring mold, the combination, with an aluminum body having therein a mold groove, an inlet port communicating with said groove, a groove for the reception of the head core, and an aperture extending transversely of the mold groove and within said groove, of a core of material, as charcoal, located in said transverse aperture and having receiving and distributing ports adapted to distribute molten metal from the inlet port to opposite portions of the mold groove, and an aluminum ring-head core in its groove provided with a project-ion of relatively non-fusible material adapted to engage the former core to center the same.

10. In a ring mold, the combination, with a body of metal to which, when unheated, molten metal will not adhere, said body having therein a mold groove, a groove for the reception of the head core and an aperture extending transversely of the mold groove and within said groove, of a core located in said transverse aperture and having receiving and distributing ports adapted to distribute molten metal from the inlet port to opposite portions of the mold groove, and a ring-head core of metal to which, when unheated, the molten gold will not adhere, the latter core being provided with a projection of relatively non-fusible metal adapted to engage the former core to center the same.

11. A ring mold comprising a pair of ture communicating with the fractional insymmetrical sections made of aluminum, let port. each section having a fractional mold In testimony whereof, I hereunto affix my groove therein and a fractional inlet port signature in the presence of tWo Witnesses.

communicating With the fractional mold FRANK C. WIDMANN. groove, and a plate of relatively non-fusible Witnesses:

metal applied to the inletend of each of J. B. HULL,

said sections and having a fractional aper- H. MILLER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G.

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