US1247470A - Non-magnetizable watch. - Google Patents

Description

Patented Nov. 20, 1917.

UNITED STATES PATENT OFFICE.

EUGENE 'r'. TURNEY, or NEW YORK, N. Y.

NON-MAGNETIZABLE WATCH.

To all whom it may concern:

Be it known that I, EUGENE T. TURNEY, a citizen of the United States and a resident of borough of Manhattan in the county of New York and State of New York, have invented certain new and useful Non-Magnetizable Watches, of which the following is a specification.

My invention relates to watches and consists of means to prevent them from being deranged by magnetic influence.

Watches as ordinarily carried are subject to various kinds of magnetic influences. When carried in a trolley car or on electric trains, the magnetic fields of the motors or generators or conductors affect the hair spring and other steel parts. In fact in those sections of the country where electricity is generally used, it is difiicult to find a locality in which a watch is not more or less aifected by electric or magnetic influences.

The result of such influences is that the hair spring varies in its periodicity. It may be stopped or very slightly affected but nevertheless sufficient to interfere with the accuracy of the time keeping parts of the watch. In fact, it is rare to find a watch which maintains any close degree of accuracy.

I have discovered that by surrounding the works of a watch, not only the hair spring and the wheel pivots but all the other working parts, by an envelop having thin side walls making it adaptable for insertion in watches without general changes in the processes or tools of manufacture; and having comparatively thicker pole pieces, that is, thicker disks on the top and bottom of the movements secured as shown by an extra layer or extra thickness of iron, the said side walls and pole pieces being made of highly magnetizable material but preferably not of material suitable for permanent magnets, that the works may be so adjusted after insertion in such a magnetizable envelop that they may be substantially perfect time keepers.

It has been proposed heretofore to surround such works with thin magnetic casings without such heavy pole pieces, and it has been proposed to surround such works with permanently magnetized envelops, but neither of these arrangements secures the result attained by my invention. The antimagnetic envelop is preferably constructed Specification of Letters Patent. Patented N 20, 1917,

Application filed June 12, 1916. Serial No.103,280. I

not to conceal the dial, so that the time can be seen without opening the envelop and without .admitting disturbing magnetic influences to the works. y

Heretofore, also, thin cases of iron in two hinged parts have been employed to contain the whole watch. Such cases have to be opened for the purpose of seeing the time.

Watches for railroad purposes must be open faced to comply with regulations concerning them; and such non-magnetic cases could not be used for that reason. Moreover, they did not prevent watches from being struck by magnetic fields and deranged thereby.

Non-magnetic watches have also been made with non-magnetic hair springs, but such watches cannot be relied upon as accurate time pieces.

My invention aims to overcome these difiiculties.

In the drawings Figure 1 is an enlarged section of my watch.

Fig. 2 is a face view thereof.

Fig. 3 is a back view with the cover removed.

In my watch an envelop of magnetic material is incorporated in the watch case. The dial 1 of the usual enamel is formed on a soft iron disk (previously copper plated if desired). This disk is preferably thick at 2-, and preferably as thick elsewhere as clearances permit. The back of the watch 4, removable by unscrewing the threads 5, has also the soft iron shell 6, and a thick soft iron disk 7, the back being preferably plated with gold or other materlal.

Between the dial and back is a soft iron shell 8, preferably connecting the two magnetically. It is held in place by the screws 9 in Fig. 3, and by its shape fitting within the middle portion 10 of the case.

The magnetic parts 1, 2, 6, 7, 8 form an envelop of material adapted to prevent the lines of force of a magnetic field from reach ing the hair spring and affecting its action. The envelop should be sufficiently thick to avoid saturation in the strongest fields into which the watch may be carried. The thickened portions 2 and '7 may at times form poles between and around which the lines of force flow.

Thus protected the watch has been found to keep the same time in a strong magnetic field as outside of it.

The middle portion 8 of the envelop is provided With the opening 11 for the stem 12 and the openings 13 and ll are made for the shafts of the hands of the Watch, so that the hands may operate outside of the magnetic envelop and enable the time to be seen Without opening the magnetic envelop. Preferably the anti-magnetic envelop is held within a gold case, so that it is not evi dent to the eye. The dial may cover the top magnetic member and gold may cover the other members.

The usual front portion 15 having the glass crystal 16 may be screwed on at 17.

Many variations may be made in the form and application of my invention, its principal features being indicated in the claim.

That I claim is An anti-magnetic shield for a Watch movement' comprising an envelop having a thin magnetizable annular portion and thicker inagnetizable top and bottom portions forming pole pieces.

Signed at New York city, in the county of New York and State of New York May, A. D. 1916, i 1

EUGENE T. TURNEY. WVitnesses:

, MYRON F. HILL,

P. I-IARNIsCI-IFEGER.

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

Washington, I). C.

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