US425020A - Manufacture of watch-dials - Google Patents

Description

UNITED STATES PATENT E ICE.

DAVID R. BUCHANAN, OF PEORIA, ASSIGNOR TO THE ELGIN NATIONAL WATCH COMPANY, OF CHICAGO, ILLINOIS.

MANUFACTURE OF WATCH-DIALS.

SPECIFICATION forming part of Letters Patent No. 425,020, dated April 8, 1890.

Application filed May 25, 1889. fierial No. 312,141. (No model.)

To all whom it mag concern.-

Be it known that I, DAVID R. BUCHANAN, of Peoria, in the county of Peoria, and in the State of Illinois, have invented certain new and useful Improvements-in the Manufacture of -Watch-Dials 5 and I do hereby declare that the following is a full, clear, and exact description thereof.

In the manufacture of watch-dials in which a metal base is coated with enamel it is customary to cover the back side as well as the face of the base for the purpose of protecting the same from the action of heat and thus preserve its form. To do this, an operative takes each base singly, and with a spatula lays upon its back side an even covering of the fine and otherwise worthless part of the powdered enamel which has been washed from the mass, such covering being applied in a wet state. The water contained in the enamel is next partially dried out by the application thereto of a towel or other suitable absorbent, after which the base is turned with its face side uppermost, and such side covered in substantially the same manner with a fine quality of enamel. After this is done the dial is permitted to stand until dry, when it is ready for firing. Such method requires an expert workman, and as but one dial can be operated upon at a time the work is slow and quite expensive.

The object of my invention is to lessen the time and labor required, and consequently the expense involved, in the manufacture of dials; and to such end said invention consists, principally, in the method employed for applying enamel to the backs of the dial-bases, substantially as and for the purpose hereinafter specified.

It consists, further, in the method employed for applying the enamel to the faces of the dial-bases, substantially as and for the purpose hereinafter shown. a

It consists, finally, in the method of enameling a dial, substantially as and for the purpose hereinafter set forth.

In the carrying of my invention into practice I employ a bath of water and fine enamel, and provide the same with means whereby the water may be agitated so as to cause the I fine particles of enamel to be suspended, in-

stead of settling to the bottom, as would otherwise be the case. Into the enamel bath thus prepared there is now immersed a fine wire sieve, in which is placed any convenient number of dial-bases, with the backs of the same uppermost. The sieve with its contents is permitted to remain in the bath until there is deposited upon the exposed back sides of the dial-bases a suitable coating of the fine enamel, aftenwhich said sieve is withdrawn, and with its contents is placed in awarmingcloset and gently heated, so as to evaporate the water from the enamel and cause it to adhere to the back of the dial-base.

The proportion of enamel to the quantity of water in the bath may be determined by test-tube observations, and the bath kept within proper limits by the addition thereto from time to time of the necessary quantity of enamel, the amount being regulated by the number of dials treated and the thickness of the deposit governed by the time the dialbases are permitted to remain in the bath. After the enamel thus deposited upon the backs of the dial-bases has become sufficiently dried, said bases are turned so that their face sides will be uppermost and the sieve then placed over a suitable receptacle, and washed and dried enamel is sifted evenly over said bases until the cup which is formed by the upward-turned edge of the same is even full, the surplus enamel falling through saidsieve into said receptacle, after which the dial-bases are placed inafurnace and fired in the usual manner.

By this method the'enamel is applied more evenly to the faces of the dial-base than is possible by the method heretofore employed, and instead of the separate treatment of each base a large number may be simultaneously operated upon by one person, the result being that the product is uniformly good and its cost materially reduced.

While Water is preferably employed for floating the fine particles of enamel and dc positing the same upon the dial-base, any other suitable liquid may be substituted therefor.

Having thus described my invention, what I claim is- 1. As an improvement in the manufacture of watch-dials, the method of coating one of the faces of a dial-base with enamel, which consists in suspending fine particles of enamel Within a suitable liquid and eausin the faces of: a dial-basc,\vl1icl1 consists, first, in

depositing upon one face by the aid of a liquid a coating of fine particles of enamel, next evaporating the liquid from such coating by i heat, next sifting finely-subdivided enamel upon the other face of said base, and finally fusing such enamel by heat, substantially as and for the purpose shown and described.

In testimony that I claim the foregoing I have hereunto set my hand this 20th day of May, 1889.

DAVID R. BUCHANAN. \Vitnesses:

D. I). Ross, L. W. CARTER.