Untitled record

Application filed November 25,1902. Serial No. 132,753. (No model.)

To all whom it may concern:

Be it known that we, Frederick W. Taylor, a resident of Philadelphia, in the county of Philadelphia, in the State of Pennsylvania, 5 and Sidney Newbold, a resident of Jobstown, in the county of Burlington, in the State of New Jersey, both citizens of the United States of America, have invented certain new and useful Improvements in Metalio Boring Tools, of which the following is a true and exact description, reference being had to the accompanying drawings, which form a part thereof.

Our invention relates to tools or devices 15 for boring metals—such as drills, reamers, countersinking devices, &c.—the object of our invention being to provide a tool for such purposes which is both of greater efficiency and of less cost than the tools heretofore gen20 erally used and our invention being in one phase ah outgrowth and involving the principle of our former invention in metal-cutting tools described and claimed in our Patent No. 709,526, dated the 23d of September, 1902, 25 said patented invention relating to the device for securing metal-cutting tools, preferably of self-hardening steel, in holders by means of a packing of fusible metal.

As heretofore practiced by us and explained 30 in our before-mentioned patent, the metalcutting tools inserted in the cavities formed in the proper holders and secured therein, as described, were exposed to a certain class of strains—such as exist in lathes, planers, saws, 35 milling-machines, and the like—such strains being quite different from those which exist in tools used for boring through metal; and our present invention consists, broadly speaking, in the combination of a cutter-holder 40 adapted to be secured to a boring-machine and having in its end transversely-extending grooves or cavities which extend on both sides of the center line about which the holder turns, said holder cavity or cavities having 4 5 their walls toward which the cutting-tools are pressed in the operation of cutting adapted to receive and form an abutment for said tools, with a cutter or cutters inserted in the cavity or cavities and having their inserted 50 portions lying in contact with the walls of the cavity against which they are pressed in operation, and a packing of fusible metal filling the spaces between the inserted portion of the tool or tools and the walls of the cavity or cavities. By preference the tools or cut- 55 tors so combined with holders are made of self-hardening steel, and the compound tool is thus adapted for more rapid and effective work than if the cutting portions thereof are of ordinary tempered tool-steel, while the ex- 60 pense of the construction is materially lessened, as the holder can be made of materials and by means which involve little expense, while practically no work is done upon the cutters themselves except providing them 65 with the proper cutting edges.

Where our invention is applied to the construction of tools for reaming out perforations already formed or for countersinking the ends of perforations already formed, a 70 single cutter of appropriate form and preferably of self-hardening steel can be secured in the holder, as will be hereinafter more fully explained; but where the tool is intended for use as a drill we have found it 75 advisable to use self-hardening tool-steel to form lateral cutters for the drill and a central cutter of tempered steel, which is better adapted to withstand the pressure and twisting strain to which the central portion of the 80 drill is exposed than are the self-hardening tool-steels, while the desired object is attained by the combination with said central cutter of the lateral cutters of self-hardening steel, enabling the hole to be bored with a 85 speed which would be impracticable if they were made of tempered tool-steel.

The detail features of our invention will be best understood as described in connection with the drawings, in which— 90

Figure 1 is a side elevation of a tool constructed in accordance with our invention, Fig. 2 being a cross-section on the line 2 2 of Fig. 1; Fig. 3, a side view of the cutting portion of the drill, taken at right angles to that 95 shown in Fig. 1; Fig. 4, a central section through the holder, taken as on the line 4 4 of Fig. 2. Fig. 5 is a perspective view of the cutting-tools used in connection with the drill; Fig. 6, a side elevation of a drilling

748,890 tool constructed in accordance with our invention. Fig. 7 is a cross-section on the line 7 7 of Fig. 6. Fig. 8 is an end view of the countersinking-tool shown in Fig. 9. Fig. 9 is a side elevation of a countersinking-tool constructed in accordance with our invention.

A A in Figs. 1, 6, and 9 indicate the portion of the tool which is adapted to be secured in the holding appliances of a boringmachine, A' A' indicating the body of the holder, which is generally made, as shown, of cylindrical form; A² A², Figs. 1 and 6, indicating spiral chip-grooves formed on the walls of the holder; a² a², Figs. 1, 2, and 3, indicating approximately longitudinal extensions of these chip-grooves at the end of the holder, formed, as shown, for the purpose of strengthening the wall of the cavity in which the cutting-tools are to be inserted.

A³ indicates a transverse groove formed across the end of the holder, which is of conical outline at this point, as indicated at a'. As shown, the transverse groove A³ is deeper at the center, as indicated at A⁴, and has at its ends supporting-surfaces (indicated at a³a³) upon which the lateral cutters of the drill rest.

A⁵ indicates another transversely-extending groove or cavity intersecting the groove A³ and by preference not extending through the walls of the conical portion of the holder, as is well shown in the drawings.

A⁶ A⁶, &c., indicate the walls of the grooves or cavities toward or against which the inserted cutting portion of the tool is pressed in the operation of boring.

a⁹ a⁹, &c., indicate the opposite walls away from which the cutting portion of the tool is pressed in working and which walls by preference are so formed as to afford a considerable space between them and the adjacent inserted portion of the tool.

Β B are separate lateral cutting portions of the tool, made of self-hardening steel, which are inserted in the groove or cavity A³, but which do not extend to the center. By preference these lateral cutting portions Β B are formed with shoulders B', which rest upon the supports a³, and with downward and inward extensions (indicated at Β² B²) which lap over each other at the center of the holder at the depressed portion A⁴ of the cavity and the upper surfaces &² b² of which are adapted to serve as a support for the central cuttingtool, which central tool is indicated at C, being preferably formed with one or more lateral grooves C² on each side, C³ indicating the cutting edges and C' the bottom, which rests upon the lapped extensions B².

The tool is assembled by inserting the lateral cutters Β B in the groove A³ with their inserted portions in contact with the walls A⁶A⁶ of the holder, toward which walls the tools are pressed in the act of cutting. The central cutter C, which is by preference made of tempered tool-steel, is then inserted in the cavity or groove A⁵, so that its base 0' will rest upon the inward extension B² of the lateral cutters and with its inserted portions 70 brought into abutting contact with the walls A⁶ A⁶ of the groove A^s, toward which walls the tool is pressed in operation. A packing of fusible metal, as described in our former patent, is then run into the spaces left between 75 the inserted portions of the tools and the walls of the cavities, filling such portions and also of course the spaces intervening between the inserted tools and solidifying, so as to combine the parts together in a manner which we 80 have found to be thoroughly efficient for boring purposes. This special form of tool embodying the tempered tool-steel has a central cutter, and the air-hardening tool-steel as lateral cutters being adapted for more rapid 85 and efficient operation than has heretofore been practicable, and obviously the cuttingtools of the drill can be readily replaced whenever broken or so worn as to require replacement. 90

In case of a drill or countersinking-reamer, such as are shown in Figs. 6 and 7, a single transversely-extending cavity (indicated at A⁷) is formed in the end of the holder, and a drilling or reaming tool (indicated at E and 95 F, respectively, and formed, preferably, of self-hardening steel) is provided with a shank or insertible portion E' or F', which is inserted in the cavity A⁷ and abutted against the walls A⁶ A⁶ of such cavity toward which the ϊοο tool is pressed in operation. The spaces between the inserted ends of the tool and the ' walls of the cavity are then filled with fusible metal, as indicated at D, and the tool is ready for use. The cutting portion of the tool in 105 this instance is formed of a single piece E or F; but in the form shown in Figs. 1 to 5 the corresponding portion of the tool is formed of two pieces Β B.

Referring again to the drilling-tool shown no in Figs. 1 to 5, inclusive, we would say that, apart from the method of assembling the parts which we have described and which we believe to be the best for its manufacture, the tool having in combination with a holder a 115 central cutting-tool of tempered steel and of less breadth than the hole to be drilled and lateral cutting-tools of self-hardening steel which do not extend to the center of the drill is new with us and is intended to be covered 120 broadly.