US72065A

US72065A - Improvement in augebs

Info

Publication number: US72065A
Authority: US
Publication date: 1867-12-10
Anticipated expiration: 1884-12-10

Description

Will

guitar tetra iatmt ffin'r.

JOHN A. McGEE,-OF NEWYORK, N."Y., ASSIGNOR TO THEODORE MACE,

OF SAME PLACE. 3

Letters PatentNo. 72,065, dated December 10, 1867.

IMPROVEMENT IN AUGERS.

TO ALL WHOM IT MAY CONCERN:

Be it known that I, JOHN A.-McGEE, of the city and State of New York, have invented and made a certain new and useful Improvement in Boring-Instruments; and I do hereby declare the following to be a full, clear, and exact description of the said invention, reference being had to the annexed drawing, making part of this specification, wherein- Figure 1 is a side view of an anger formed with my improved cutting-edge.

Figure 2 is a view endwise of the said auger; and

Figure 3 is an elevation at right angles to fig. 1.

Similar marks of reference denote the same parts.

Boring-tools have heretofore been made, in which the cutting-edges have been made of two parts, the one acting to form a circular incision, the other to clear out the wood. In'augers of this kind a difliculty is experienced in sharpening the cutting-edge, particularly in small angers. Augers' have also been made with the cutting-edge curved upwards or towards the handle, but with these the cutting of each shaving of the wood extends entirely across the cutting-edge, and the shaving at the outer edge is very thin, in consequence of the convergence of the arcs described by the cutting-edge, the same as in a pod-auger, and after the screw-point has passed through the wood, and no longer draws the'auger along with regularity, there is a' difiiculty in finishing the hole with a smooth cut..

The nature of my said invention consists in a boring toohin which the cutting-edge is extended outwardly from the base of the tapering screw, and curved backward and downward until it intersects the periphery of the itool; thereby a circular incision is first made by the revolution of the tool, and then a'shaving is removed by the hither parts of the same cutting-edge. This character of cutting-edge is sharpened almost entirely by filing'upon jthe lower surface, where there is easy access; hence the tool is kept in order with facility..

In the drawing, a represents a portion ofthe twist of the auger, b the conical screw-point. The cuttingledges 2' are formed nearly straight, and as tangents to the base of the screw 6, as atl; thence the cutting-edges are formed as compound curves, at 2, slanting backwards, so as to separate the grain of the wood by a shearing cut, and curving downwards, or towards the screw-point, so as to separate the wood by a circular incision, in gadvance of the part 1 of said edge which removes the wood. i The cutting-edge in my said tool being a. compound curve backwards and downwards, is a shearing out lthroughout its entire length. The shaving that is removed is curled in the act of being cut, so as to easily free iitself as the screw portion of the bit passes it along. The bit can be filed and sharpened with ease; and the last iportion of the wood removed, when the hole is bored through, is in the form of a. disk around the screw-point, iand the cut is free andsmooth through its entire length. i

What I-claim, and desire to secure by Letters Patent, is The boring-instrument formed with a cutting-edge extending outwardly from the base of the tapering screw, land curved backwards and downwards until it intersects the periphery of the tool, as and for the purposes iset forth. a In witness whercofl'I havehereunto set my signature, this 20th day of June, A. D; 1867.

- Y JOHN A. McGEE.

Witnesses: Gno. D. WALKER, l Giro. T. PINCKNEY.