US2347920A - Abrasive wheel - Google Patents

Description

lJ. C. MAYS ABRAS IVE WHEEL May 2, 1944.

Filed March 27, 1941 Patented May James C. Mays, Niagara Falls, N. Y. assignor to The Carborundum Company, Niagara Falls, N. Y., a corporation ot Delaware Application March 27, 1941, Serial No. 385,407'

' (c1. 5mi-.309)

12 Claims.

This invention relates to metal-bonded abrasive articles. More particularly, the invention relates to thin metal-bonded abrasive articles.

such as cut-oli wheels, in which the vbond metal is deposited in situ electrolytically.

One of the objects of my'invention is to provide thin abrasive wheels, such as cut-oil' wheels, in which at least the outer-working portion of the wheel is composed wholly of abrasive particles bonded with electro-deposited metal, thereby producing abrasive articles of novel characteristics. a In making abrasive articles of certain types, the use of very hard abrasive such as diamond is desirable. Diamond abrasiveis, however, so extremely expensive that, while the ordinary commercial abrasives are sold for about live cents per pound, diamond abrasive sells for around two thousand dollars per pound. It will be obvious, therefore, that in commercial practice when u'sing diamond abrasive in the manufacture of abrasive articles the Iquantity of abrasive which can economically be used will be very small, and that the diamond `abrasive particles must be very firmly held inthe matrix of bond metal so that most or all of their potential usefulness as an abrasive is exhausted before they are released by the bond metal.

I have found that abrasive particles disposed in a single layer can be iirmly and permanently heid by a single layer of metal `electro-deposited in situ about them so that the abrasive particles are embedded in a matrix of such metal. The abrasive particles are held so rmly that the resulting structure makes a very eilicient cut-o wheel for use on even the hardest materials.

The invention will be more readily understood by reference to the accompanying drawing in whichFig. 1 is a view in plan of a cut-.oil wheel v made in accordance with the present invention,

. Fig. 2 is an enlarged fragmentary sectional view of a cut-od wheel of the type shown in Fig.

2, the view being taken along the line `2--2,.in

disc. The center-of the disc is provided with an arbor hole 3. Disc I is made with its thickness Bysuitably removing small amounts of electrodeposited metal frorthe side faces of 4the disc I, the abrasive particles may be exposed on both side faces of the cut-2E wheel, as shown in Figs. 1 and 2.

. In Figure3, which is a fragmentary sectional viewtakenalong the line 3 -3 in Fig. l, is shown the structureof a cut-off wheel ofthe type de.

. wheels, such as cut-oil wheels, covered by the present invention, by electro-deposition of metal on abrasive particles. By the use of this apparatus a cut-off wheel can be made which is the apapproximately that of the diameter of the largest abrasive particles in the wheel, so that the abrasive particles have their outer surfaces lying sub-v stantially in the vplanes of the-side faces of disc I.

proximate thickness of the diameter of the largest abrasive particles in the wheel. In Figure 2 a vessel 4 of non-conducting material such, for

v example, as glass, is used. Supported on the -bottom of vessel 4 and centered by ring 5 is a plate 6 also of insulating material, such as a phenolic resin, in which is embedded a circular disc' I of metal, such as copper, having a centrally located ho1e s therethrough. Extending partially into hole 8 is an insulating tube 9 within which is a wire III by which an electrical connection may be made to disc 1 through spring contact II attached to wire I0 and pressing against the sides of hole 8 in disc 1. Suspended from the upper edge of vessel 4 is an anode I2 of circular crosssection.

In the use of the apparatus shown in Figure 2, disc 1 is coated with a material such, for example, as a thin electro-deposited layer of lead, which will act as a parting layer, and is then placed in cell 4 and assembled with tube 9 and electrical connections I0 and I I. Since in making cut-olf wheels it is usually unnecessary and when using costly abrasives such as diamond it is undesirable to have abrasive throughout the wheel, only the wheel rim contains abrasive. This is provided for in my invention by sliding over spacing washer I3 on tube 9 a cylindrical, nonconducting tube I4 which isallowed'to rest on dise 1 thus leaving exposed a peripheral ring I5 of disc 1 .of the desired size, the cell 4 having already been filled with plating solution. Abrasive particles are then vintroduced at the surface of the electrolyte in cell 4 around tube I4 and allowed to fall on the exposed portion I5 oi disc 1, care being taken to obtain a uniformly distributed deposit of abrasive. VTube I4 is theirv acid to dissolve from the wheel sum By the above-described method cut-oil? wheels much thinner .than those obtainable by other methods may be produced. This is because of the fact that the electro-deposited metal bond is much stronger than bonds obtained by such methods as sintcring. When suitable abrasive is used they are capable of use in cutting costly materials such as gems, quartz crystals, hard metal carbides and the like. It will be obvious that thicker wheels may beproduced by supplying additional abrasive as the plating is continued so that the wheels may be of any desired thickness.

Any desired abrasive may be used in the abrasive wheels disclosed herein, butthe wheel of the present invention isI particularly advantageous when used with diamond abrasive, the high cost of which necessitates a very rm bonding of the abrasive particles so that the valuable abrasive is not pulled out nor dislodged. Moreover, various metals and alloys such as copper, brass,

of each grain is exposed 'at each oi' the radial faces of the disc.

2. An abrasive cut-01T wheel as set out in yclaim 1 in which the electrolytically deposited metal is nickel.

3. An abrasive cut-of! wheel as set out in claim 1 in which .the electrolytically deposited metal is chromium.

4. An abrasive` cut-oil' wheel as set out in claim 1 in which the electrolytically deposited metal is copper.

5. In an abrasive cut-off wheel. a thin disc of electrolytically deposited metal, abrasive grains supported in an annular peripheral bandin said disc, -substantially all of said grains extending .therethrough so that a portion of each grain is exposed at each of the radial faces or said disc.

6. An abrasive cut-oil wheel as set out in claim 5 in which .the electrolytically deposited metal is nickel.

'1.'An abrasive cut-oil wheel as set out in claim 5 in which the electrolytically deposited metal is chromium. l

8. An abrasive cut-olf wheel as set out in claim 5 in which the electrolytically deposited metal is Coppel'. t

9. A thin cut-off wheel consisting of a thin discA of electrolytically deposited metal having abrasive grains substantially uniformly dissilver may be electro-deposited as a bond for the abrasive though in general, it may be desirable to use harder metals and alloys, such as nickel or chromium.

It will be obvious that modincations may be made in the abrasive wheel disclosed, and I therefore do not wish to be limited to the precise structure of the abrasive wheel described but only by the scope of the appended claims.

I claim:

1. In an abrasive cut-oil wheel, a thin disc of electrolytically deposited metal, abrasive grains supported in said disc substantially all said f grains extending therethrough so that a portion tributed therethrough, the electrolytically deposited metal directly contacting the surfaces of the abrasive grains, a portion of said `grainsbeing exposed on both the radial surfaces and on ...fthe peripheral surface of the disc. v

10. A thin cut-o wheel as set out in claim in which the electrolyticallydeposited metal is nickel.

11. A thin cut-o wheel as set out in claim 9 in which the electrolytically depositedl metal is chromium.

12. A thin cut-ofi. wheel as set out in claim 9 in whichthe electrolytically deposited metal is l.

copper.

JAMES C. MAYS.

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