US767216A - Apparatus for vacuously depositing metals. - Google Patents

Description

QEST AVAILABLE cow U. QM

P I m m mi m Dvwm E R 10 AUN m T M m Rm OP PA S U T A .R A P P N0 MODEL.

Witnesses Inventor Attorney BEST AVA BLE COP? 110 767,216. PATENTED .AUG. 9, 1904.

T. A. EDISON. I APPARATUS FOR VAGUOUSLY DEPOSITING METALS.

APPLICATION FILED AUG.1. 1903.

30 MODEL. a SHEETS-SHEET 24 .7 Witnesses w 5 Inventor ttorney BEST AvAxLABLE ('30P PATENTED AUG. 9, 1904.

T. A. EDISON. APPARATUS FOR VACUOUSLY DEPOSITING METALS.

APPLICATION FILED AUG.1. 1903.

3 SHEETSSHEBT 3.

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Inventor Witnesses m mm w Attorney UN TED STATES BEST AVAlLABLE COP Patented August 9, 1904.

PATENT OFFICE.

THOMAS A. EDISON, OF LLEVVELLYN PARK, NEW JERSEY, ASSIGNOR TO NEW JERSEY PATENT COMPANY, PORATION OF NEIV JERSEY.

OF ORANGE, NEW JERSEY, A COR- APPARATUS FOR VACUOUSLY DEPOSITING METALS.

SPECIFICATION forming part of Letters Patent No. 767,216, dated August 9, 1904.

Application filed August 1, 1903.

To all whom it may concern:

Be it known that I, THOMAS A. EDISON, of Llewellyn Park, Orange, in the county of Essex, State of New Jersey, have invented certain Improvements in Apparatus for Vacuously Depositing Metals, of which the follow ing is a description.

My invention relates to an improved apparatus for more expeditiously carrying into effect the process for depositing metals in 'vacuo of the general character covered by my PatentsNo. 526,147, of September 18, 1894, and No. 713,863, of November 18, 1902.

The apparatus has been designed particularly for depositing on phonograph-records a minutely thin film of vaporized metal which shall act as a foundation for the heavier electroplated deposit in order that a matrix or mold of such a record may be secured.

With my improved apparatus I utilizea plurality of phonograph-records or other objects to be coated in the same vacuum-chamber and simultaneously deposit the metal on such objects by maintainingahigh-tension discharge between electrodes formed of the metal to be deposited. This materially facilitates the process, since considerable time is occupied in mounting and sealing the vacuum-chamber and in exhausting the same.

I find in the practical operation of my process that if the electrical discharge is maintained continuously between the metallic electrodes, and particularly if the latter are very thin, as is preferable, the electrodes become objectionably heated and may in time actually melt, so as to destroy their utility. This objection could of course be overcome by periodically interrupting the current, so as to permit the electrodes to cool; but, as it is preferable that the induction-coil and other electrical apparatus, as well as the mechanical and magnetic appliances, should operate continuously, I secure the desired result by employinga pair of exhausted chambers in which the depositing takes place alternately, so that during the time that metal is being deposited on the object or objects in one chamber the Serial to. 167,930. (No model.)

electrodes of the other chamber are permitted to cool.

The present invention not onlyrelates to the details of construction and arrangement already indicated, but it relates also to further constructional details, all as will be more fully hereinafter described and claimed.

In order that the invention may be better understood, attention is directed to the accompanying drawings, forming a part of this specification, in which- Figure 1 is a front view of the apparatus for use in coating four phonograph-records and showing the circuits diagrammatically; Fig. 2, a cross-sectional view through one of the vacuum-chambers; Fig. 3, a vertical sectional view on the line 3 3 of Fig. 2, and Fig. 1 a separate detailed View of one of the electrodes and its support.

In all of the above views corresponding parts are represented by the same numerals of reference.

The base 1 is provided with supports 2, on which are mounted the base-plates 3, made, preferably, of glass. Extending up through the base-plates 3 are glass tubes 4, carrying circuit-wires 5 5. of these conductors are electrodes 6, made of the metal which is to be deposited and preferably in the form of thin strips of foil. For the coating of phonograph-records I preferably use gold, owing'to the fact that it may be highly comminuted and also because of its nonoxidizable character. I find that the best results are secured and the most even coating obtained when the electrodes are perfectly flat, and I therefore preferably attach a small weight 7 to the bottom of each to effect this result.

Mounted on the plate 3 is a metal rim 8, within which is placed a glass bell or jar 9, having a flanged lower end resting on said plate. A layer of parafiin 10 or similar Wax like sealing material in molten condition is now fi awed into the space within the rim 8, so as to make a perfectly-tight joint. Air from within the glass jar or hell 9 is exhausted Depending from the ends therefrom through a pipe 11, connected with a vacuum-pump of. any suitable and approved type. Vvithin the vacuum-chamber are one 7 or more supports 12, which carry vertical shafts 13, having tapered upper ends.

Surrounding each of these shafts is a sleeve 14, provided with a hardened bearing-cup at its top, which engages the shaft 13. The lower end of the sleeve 14; carries a disk 16, which receives the record or other object 17. Extending up from the sleeve 14: are arms 18, which receive arernovable armature 19.

The phon ograph-record or other object preferably carries at its top a guard or shield 20, which fits within the top of the record 17 and is supported thereby. This guard may be of any material, brass being preferably used by me. The guard receives the metal which would ordinarily be deposited within the interior of the record 17, and when made of brass it appears to. deflect the electrical discharge in a downward direction against or toward the outer surface of the record. The guard thus prevents the metal from depositing on the inside of the object and causes the metal to deposit evenly on its edge with a I clear line of demarcation, so as to permit a uniform electroplating, as will be understood.

Mounted outside of each of the vacuumchambers is a magnet 21, removably carried at the lower end of the shaft 22, mounted in the bearing 23 and rotated by a belt-wheel 2 1, to which power is applied. In order to operate the vacuum-chambers alternately to per- .mit the electrodes within one to cool while circuit 28 of an ordinary induction-coil. The

other side of this secondary circuit connects with the switch 25 through the clockwork mechanism, as shown.

The primary circuit 29 of the induction-coil is connected in multiple with the source of supply 30 and includes a circuit-breaker 31, as is common in this art. In operation a proper vacuum is created in the two chambers, and by means of the switch 25 the induction-coil will be connected alternately, first with the electrodes of one chamber and then with the electrodes of the other chamber. The discharge is so regulated as to secure between the elect'rodesa silent or brush discharge, as I describe in my patent last referred to. This discharge causes the metal composing the electrodes to be vaporized and deposited on the objects. The magnets 21 are simultaneously rotated, so as to rotate the objects, whereby a'perfectlyuniform film will be deposited thereon. When this film is of the desired thickness, the bells or jars 9 are removed, thereby permitting the coated objects to be removed for subsequent treatment, whereupon the operations described are repeated.

Having now described my invention, what I claim as new therein, and desire to secure by Letters Patent, -is as follows:

1. In vacuous deposit apparatus, the combination with an exhausted chamber with metallic electrodes therein and means for effecting an electrical discharge between said electrodes, of supports within the chamber and between the electrodes for sustaining a plurality of objects to be coated, and means for simultaneously rotating said objects, substan tially as set forth.

2. In vacuous deposit apparatus, a weighted metallic foil-like electrode, substantially as and for the purposes set forth.

3. In vacuous deposit apparatus, an electrode-foil supported at its upper end and a weight carried by said foil at its lower end, 7

substantially as set forth.

4. In vacuous deposit apparatus, a shield or guard carried by the upper edge of the ob ect to be coated, substantially as and for the purposes set forth. j

5. In vacuous deposit apparatus, the combination with an exhausted chamber and electrodes therein, of a vertical shaft within said chamber, a sleeve rotatably mounted on said shaft, and a disk carried by said sleeve for supporting the object to be coated, substantially as set forth.

6. In vacuous deposit apparatus, the combination with an exhausted chamber and electrodes therein, of a vertical shaft within said chamber, a sleeve rotatably mounted on said shaft, a disk carried by said sleeve for supporting the object to be coated, a removable armature carried by said sleeve, and a magnet mounted ex'ternallypf the chamber for attracting and rotating said armature, substanelectrodes therein and supports for objects to be coated in said chambers, of a source of high-tension current, and means for automatically and alternately connecting said source means for automatically and alternately conconnecting said source with said electrodes in necting said source with each pair of elecpairs. I

trodes, substantially as set forth. This specification signed and witnessed this 10. In vacuous deposit apparatus, in combi- 30th day of July, 1903.

nation, a plurality of supports for objects to THOS. A. EDISON.

be coated, a plurality of electrodes supported Witnesses: 'm cacao, a source of high-tension current FRANK L. DYER, and means for automatically and regularly WILLIAM A. DOLAN.

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