US1329370A - Means for holding diamonds during abrasive treatment - Google Patents

Description

0.1. COLEMAN. MEANS FOR HOLDING DTAMONDS DURIVNG ABRASIVE TREATMENT.

APPLICATION FILED JULY 20,1912. 1,329,370. Patented Feb.3, 1920.

IIWEIVTOR rasive Treatment, of which the following is and polishing diamonds CLYDE J. COLEMAN, or NEW ROCHELLE,

MEN'IS, TO s'mnn-comnan DIAMOND or NEW YORK.

mw xoax,,nssxcnoa, BY vrnsnn ASSIGN- MACHINE COMPANY, me, A conronArroiv MEANS FOR HOLDING DIAMONDS DURING ABRAS'IVE TREATMENT,

To all whom it may concern: I

- Be it known that I, CLYDE J. COLEMAN, acitizen of the United States, residing at New Rochelle, in the count of \Vestchester and State of New York, liave invented a certain new and useful Improvement in Means for Holding'Diamonds During Aba specification, reference being had therein to theaccompanying drawings, forming part thereof. v My invention relates to the art of cutting or the abrasive treatment thereof, and relates more particularly to means for holdin the diamond during the cutting and polis ling operations or during the. polishing operation. Objects of my invention are to securely hold the diamond with, exposure for polishing of all parts above; or below the girdle of the diamond, andto save time in attaching and in releasing the diamond from its holder, and

to do away, to a large extent, with the skilled manipulation now necessary in d1amond polishing operations. p The polishing of diamonds as d1st1ngui'shed from that of other precious stones 7 presents peculiar difliculties because of the i considerable heat is polishing operationl extreme hardness of the diamond and because it has to be subjected to great pres sure. and friction with the result, also, that neratedduring the eretofore two general means have been employed for holding the diamonds in this device is very to adjwitflo asto diamondduring polishing. The most common of these is to partially embed the diamond in a of metal in asemi-molten,

state, containe in asmall brass basin or dop, the vdiamond being matrixed in and held by the metal "in which it is embedded, after this metal hasanooled. In polishing way, it is necessary. from time to time to the holding metal and readjust the diamond in order that a difierent part thempimaybe exposed for polishing, and it is not possible to ex ose at one time all partsof the diamond a ve or .below its girdle: The ,other 'diamondholding means referred to 'consists of a clamp which is pressed against the stone and locked in position, but this clam mg I i Specification of'Letters Patent. Application filed July 20, 1912. Serial No. 710,621.

- quent Y readjustment :a' holding held by the cement, this arbor being composed of a refractory material having sub- .mentof the kind described,v an posed of any suitable material g stantially the same coefficient of expansion Patented Feb. 3, 1920.

the diamond at the correct angle, and'fre is necessary. Many precious stones other, than diamonds may be held during polishing by ineansof wax or cement, and even diamonds may be so held for the roughing out or. bruting operation,

but not for polishing because of the great pressure required and friction and heat developed during the polishing of a diamond, the heat thus developed being sufiicient to melt the wax or the diamond cutterscement-used in brutin l I My present invention includes a cement of fully withstand the heat of polishing the diamond and to adhesivelyhold the diamond during the polishing operation, and my invention also includes a cement for this purpose which has substantially thessame coeflicient of expansion as the diamond or sufficient" elasticity heat developed will not loosen the ment, and

the polishing operation diamond from the cemy invention also comprehends ar or to which the diamond is stantially the same coefficient of expansion as the cement and diamond.

It is to be'understood that my present invention broadly comprehends a diamond holding, cement, which will hold the dia mond by adhesion and which possesses substantially the same coefficient of expansion as thediamond or which will not loosenor deteriorate under the heat of polishing, and

. a cement-of this nature may include carbon or may be composed of a fusible material,

provided its temperature of fusion is sufiiciently high, such as enamel. My'present g Vc, so that the high such a nature as to be adapted to success- 5 invention further broadly comprehends, in.

combination with a diamond arhorcomhaving subas the cement, good examples of such materials being carbon, porcelain, 'glass, quartz, etc; The broad invention of the cement and arbor is broadly claimed herein and the carbonaceous cement and carbon arbor are more specifically claimed herein, while the jnsiblefcement, such as above indicated, is

holding ce-,

broadly and specifically claimed in another application filed on even date herewith, Se.- rial Number 710,622.

\Vhileuny,present invention is directed more particularly to obtaining a satisfac' tory solution of the peculiarly difficult problem of holding diamonds during the polishing operation, it also presents a distinct advantage in that it1may be employed to hold the diamonds during the preceding operation of cutting or bruting, thereby doing.

away with the present necessity of transferring the diamond from the holding means employed for bruting to the other different holding means employed for polishing, involving the necessity of re-centering the diamond. Therefore, in the practice of my invention, I may cement the rough or uncut diamond-to an arbor embodying my invention by means of a cement embodying. my invention, and first brute or rough out the diamond in any suitable way, for example, in a lathe, and then takethis same arbor, with the bruted diamond attached, and put it into a holdin device and polish the diamond, without t ie necessity of having to transfer the diamond to another arbor.

I shall now describe my invention with reference. to the accompanying drawing illustrating one embodiment thereof, and

shall thereafter point out my invention in claims.

The drawing is 'an elevation, partly in vertical section, of a diamond holder embodying my invention.

The diamond 1 has previously been roughed out or bruted to a substantially regular rounded form. The bruted diamond is shown as held tothe cupped end of a c; -bon arbor 2 by means of a body of carbonaceous cement 3. This cement will not be softened by the heat of polishing the dian'iond and, because of the fact that the cement 3 and the arbor 2 have substantially the same coefficient of expansion as the dia mond 1, the expansion of the diamond under the heat of polishing will not loosen it from the arbor.

The carbon stick or arbor 2 may be of the same composition as the well known electric are light carbons. The carbonaceous cement 3 may be composed of powdered coke. rye flour and gum shellac, or may be of other suitable composition. This cement maybe made by all of the ingredients being ground and masticated together with water or thin molasses. Another formula and suitable proportions of the ingredients thereof is 75 parts finely powdered anthracite coal, 25 parts finely powdered gum shallac, 50 parts boracic acid, parts chlorid of magnesium or chlorid of calcium and a suflicient solution of carameled cane sugar to make the whole into a stiff paste. Instead prising a diamond-holding adhesive cement having resistance to heat above the temof the cane sugar, though less suitable, a solution of coal tar may be employed as a carbonaceous binder. In attaching the diamond 1 to the arbor 2 with this cement, the cement is applied cold and baked at a high temperature for thirty minutes out of contact with the air, to carbonize the cement so that the diamond will be held by adhesion. To remove the diamond 1 from the arbor 2, the diamond is snipped off with a pair of cutting pliers.

The arbor 2 i tapered, as shown in the drawing, and is inserted in acorrespondingly flared bore in a dop' head 4 provided With a tubular shank The arbor 2 may be loosened from the dop head 4 when desired by turning a thumb screw 6 screw-threaded into the outer end of the shank 5, this screw being provided with a stem 7 extending withinthe' bore of the shank 5 and adapted to push out the arbor'2.

The other parts of the diamond-holding tool'may be of any suitable construction and the holder illustrated in the drawing is of a usual construction and its operation Will be readily understood without thenecessity of a particular description of those parts which do not directly relate to the present invention. The diamond 1 is shown as held in position for polishing on a lap 8, a portion only of which is illustrated in thedrawm It is'obvious that various modifications may be made in the construction shown in r the drawings and above particularly de- 100 scribed within the principle and scope of my invention.

I claim:

1. Means for holding a diamond comhaving resistance'to heat above the'temperature produced in diamond polishing, and an arbor having substantially the same co'eificientof expansion as the cement and to which the cement is attached by adhesion to hold the diamond on the arbor.

2. Means for holding a diamond comprising an arbor, and a carbonaceous cement for holding the diamond to the arbor.

3. Means forholding a diamond comprising a carbon arbor, and a carbonaceous cement tor holding the diamond to the arbor.

4. Means for holding a diamond comprising a diamond-holding adhesive cement perature produced in diamond polishing and also having substantially the same coefliicient of expansion as the diamond, and an arbor having resistance to heat above the. temperature produced 'n diamond polishing and also having substantially the same coefiicient of expansion as the cement and to which the cement is attached by adhesion to hold the diamond on the arbor.

5. Means for holding a diamond comprising an arbor, and a carbonaceous cement for holding the diamond to the arbor, the cement including carbon, a resinous substance, a boron compound, a mineral salt and a carbonaceous binder.

(3. Means for holding a diamond comprising an arbor, and a carbonzueous cement for holding the diamond to the arbor, the cement including carbon, a boron compound, a mineral salt and a carbonaceous binder.

7. Means for holding adiamond comprising an arbor, and a carbonaceous cement for holding the diamond to the arbor, the cement including a boron compound, a mineral salt and a carbonaceous binder.

ing, and having substantially the same coctlicient of expansion as the diamond, and an arbor for holding said body.

In testimony whereof I have aflixed my signature in presence. of two Witnesses.

CLYDE J. COLEMAN.

\Vitnesses:

WM. ASHLEY KELLY, VICTOR D. Bonsr.

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