US1498221A - Method of making watchcases - Google Patents

Description

June 17 1924.

1,498,221 E. M. WISE METHOD OF MAKING WATGHCASES Filed July 27. 1925 INVENTOR [I ATTORNEY Patented June 1 7, 1924.

UNITED STATES 1,498,221 PATENT OFFICEQF",

EDMUND MERRIMAN WISE, or CINCINNATI, oHIo, ASSIGNOR To THE wanswoa'rn WATCH CASE COMPANY, OF DAYTON, KENTUCKY, A CORPORATION OF KENTUCKY.

METHOD OF MAKING WATCITGASES.

Application filed July 27, 1923-. Serial No. 654,108.

To all whom it may concern:

Be it known that I, EDMUND MERRTMAN VVIsn, a citizen of the .U. S., residing at 1105 Elm Street, Cincinnati, in the county of Hamilton, State of Ohio,have invented certain' new and useful Improvements in Methods of Making VVatchcases; and I do hereby declare the following to be, a full,

clear, and exact description of theinvention,

such as will enable others skilledin the art to which it appertains to make and usethe same.

This invention relates to methods of making watch cases, and, more particularly, to a method of making solid gold watch cases by means of dies designed for the purpose of shaping watch case stock having a thickness considerably greater than that of the stock out of which the solidgold watch cases are made. relates particularly to a process whereby a watch case can be made out ofthin stock by using dies designed for the purpose of handling relatively thick stock.

The general practice in making solid gold watch case backs consists in casting an ingot of a suitable gold alloy, and rolling the ingot down, with suitable intermediate annealing,

to substantially the thickness required for the watch case. For example, the stock may be rolled to its ultimate thickness plus .0005 of an inch andthen cut up into blanks which are stamped with a serial number and trade ing and turning operations, and the joints, if any, are soldered on. The back ispolished and it is then complete. I I

The bezel and center are made in substantially the same manner in which the watch case back is made, although in making the center the press is relied upon only to form the metal very roughly into the required shape, the final forming being done by spinning. Subsequent to the spinning operation the center is turned on the inside-to lighten it, the joints, lugs, etc. are soldered in place and then the center is polished.

In other words, thisinvention It is oftentimes desirable to make a series of watch cases, each having substantially the same external dimensions, but the several cases of the series being made of gold stock of different thicknesses. If this were to be done in the ordinary manner, a different set of dies'would be required for each thickness. Heretofore it has not been considered possible to use a set of dies designed to be used with watch case stock of a given thickness,

for shaping stock substantially thinner than that for which the dies were designed. Accordingly, the principal object of the present invention is to provide a process of making watch cases whereby a single set of dies may be used for making cases out of stock of different thicknesses. 1s ZLCCOIHPllShGCi by increasing the effective thickness of the thin stock merely for the I purpose of putting it through the dies. This can be done by applying to the stock a layer of base metal so as to increase the elfective 1 thickness of the stock the desired amount. After the stock has been shaped by means of the dies, this layer of base metal is removed.

The various details of the preferred embodiment of this invention will now be de scribed with reference to the accompanying drawings, 1n which Fi 1 is a plan view of a blank consisting of so id gold stock to which a layer of base metal has been applied for the purposeof incrlgasing the effective thickness 7 of the stoc i Fig. 2 is an elevation of the blank illus trated in Fig. 1, showing the two layers of metal.

Fig. 3 is a transverse section view of a watch case back formed from the composite blank illustrated in Figs. land 2.

Fig. 1 is a plan View of the watch case back shown in Fig. 3, part of the layer of base metal having been removed.

Fig. 5 is a transverse sectional View of the watch case back shown in Fig. 4, and

Fig. 6 1s a transverse sectional view of a watch case back formed from a composite blank, the layer of base metal being on the inside of the watch case back- In carrying out the preferred embodiment of my invention,I apply to the watchcase stock a layer of base metal such as copper,

the thickness of the layer of base metal being sufficient to increase theeffective thick ness of the stock so that it can be handled In general, this object derstood that the term solid gold as used throughout this description and the appended claims includes all metals which are used for the purpose of making Watch cases. The solid gold stock should be rolled to substa'n'ti'ally its ultimate thickness before the layer of base metal is applied thereto, for if the metal has to be rolled considerably after the base metal is applied thereto, ob-

jectionable irregularities areapt to be formed on the surface of the gold.

The layer of base metal may be applied to the solid gold in any suitable manner, the

.only limitation being that the layer of base metal must not be applied so as to appreciably impair the surface of the watch case stock. v He'retofore, certain watch case parts have been made out of composite stock formed by sweating or soldering a layer of base metal to a layer of gold and rolling the compositebar down to the desired thickness, after which the usual mechanical operations are performed and the base metal removed. Thisprocess is not suitable for the making of solid gold watch case backs,or for any other, purpose which requires the surface of the underlying precious metal to be preserved in its original form. The surface of the gold Where it has :been in contact with the base metal is rough, this probably being due to the slight penetrationof the solder used to form a composite bar, and partly due to the deformation taking place during the rolling operations necessary to reduce the stock'to its ultimate thickness.

One of the important features of the present invention consists in applying 'the layer of base metal only after the gold stock has been rolled to substantially its :ultimate dimensions. This feature effectively removes the danger of impairing the surface of the gold stock by rolling it after the base metal has been applied thereto.

Furthermore, the base metal should not be applied to the (gold stock in such a manner that it will alloy with or penetrate the gold to any appreciable extent. I have found that very satisfactory results can be ob tained by electroplating the layer of base metal on tothegold stock. 'By this means the efie'ctive thickness of the stock can be increased to the exact value desired, f and when the base metal 'is removed the underlying surface of thegoldis preserved in its origevent, the gold stock should be rolled to substantially its ultimate thickness before the layer of base metal is applied thereto.

The watch case blank shown in Figs. 1 and 2 has been stamped from con'rpositestock 'con-' sisting of a layer 1 of solid gold or other watch case metal, and a layer 2 of base metal which has been applied to the gold stock, preferably by electroplating. The underlying gold stock may have a thickness of, for example, .012 of an inch,and if thisstock is to be put through dies designed for stock having a thickness of .022 of an inch, the layer 2 of base metal should have a thickness of .010 of an inch.

Fig. 3 shows the blank of Figs. land 2 drawn into a shallow cup, the configuration of which is substantially the same as that of the finished watch case back. This cup is subjected to the'usual turning operations, and then the layer of base metal is removed by means of a suitable acid.

Figs. 4 and 5show a watchcaseback with a part of the layer 20f base metal removed, revealingthe layer 1 of solid gold. I have found that by applying "the layer of base metalafterthe gold stock has been rolled to that shown in Fig. 3 except that the layer 2 of base :metal is deposited on't'he "inside of the layer l of solid .gold instead of on the It is immaterial whether the com outside. posite stock be shaped so that the layer of base metal is on 'the inside oron the outside. For some purposes :it may be preferable 'to have the layer of base metal "on the inside. In either case, this layer of base metal is removed r after the case is complete- I ly formed.

This invention is not limited to the particular embodiments scribed, but includes such modifications thereof as fall withinthe scope of the appended claims.

1. The process ofmaking-"solid golcluvatch cases, which'consists iniprovidin-g solid gold stock rolled to substantially its ultimate thickness, applyingto the gold stock a layer of base metalv in such a manner that the adjacent surface'of the goldstock isnot 'appreciably affected by the application'ofthev layer of base metal, shaping the composite illustrated land demetal into a Watch case Without first reducing the thickness of the composite metal, and removing the layer of base metal.

2. The method of making solid gold Watch cases which consists in providing solid gold stock rolled to substantially its ultimate thickness, ornamenting the gold stocl;,'applying to the ornamented surface a layer of base metal to increase the effective thickness of the stock to a predetermined value, shaping the composite stock by means of dies adapted to shape metal having a thickness equal to the predetermined value, and subsequently removing the layer of base metal.

3. The method of making solid gold Watch cases, which consists in providing solid gold stock rolled to substantially its ultimate thickness, electroplating a layer of base metal on to the gold stock to increase of dies adapted to shape metal having a v thickness equal to the predetermined value, and subsequently removing the layer of base metal.

4E. The method of making asolid gold Watch case by means of dies adapted to shape metal having a thickness substantiall greater than that of the solid gold stoc: out of Which the case is to be made, which consists in increasing the eifective thickness of the solid gold stock by electroplating thereon a layer of copper, shaping the composite stock by means of the dies, and subsequently removing the layer of base metal.

In testimony whereof I afiix my signature.

I EDMUND MERRIMAN \VISE.

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