IMPROVEMENTS IN DRILLS AND BITS AND HOLDERS THEREFOR
Year: 1886

page_text: WHE
.
I, SIMON PETER GRAHAM, of the Town of Galt, in the Province of Ontario,
in the Dominion of Canada, Machinist, do hereby declare the nature of my
Invention for "IMPROVEMENTS IN DRILLS AND BITS AND HOLDERS THEREFOR
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :—
This invention relates to improvements on shanks of drills for boring iron, or
shanks of bits, for boring wood or any boring tool where a holder is required to
hold it while rotating same.
And this invention consists of a drill or wood bit, in the shank of which two
grooves are formed, to which grooves the jaws or prongs of the holder are fitted,
so as to hold said drill or bit while it is being rotated.
The object of this invention is to form two grooves in a drill or wood bit shank,
and adapt the adjacent jaws or prongs of a holder, to fit the same, so that the jaws
or prongs in one holder, will fit the grooves in drills of various sizes.
Reference being had to the accompanying drawings wherein
Fig. 1. is a side elevation of a holder, embodying my invention.
Fig. 2. is another view of same, partly in section.
Fig. 3. is a perspective view of same with the sleeve removed, and a drill shank
inserted between the jaws thereof.
Fig. 4. is a perspective view of my improved holder, showing jaws or prongs.
Fig. 5. is a perspective view of a drill, showing the grooves in the shank, to
which is fitted the jaws or prongs of the holder.
Fig. 6. is a cross sectional view on the line, x, x, of Fig. 3.
Fig. 7. represents various sizes of drills held by one holder, as the metal between
the grooves in the small drill.is the same thickness, as in the drill of a larger size,
in each of which the angle of the groove is the same, thereby enabling the holder
to firmly hold a large number of drills, of various sizes.
)

page_text: A, designates a drill in the shank, B, of which two grooves, C, C, are formed,
which with the grooves in the cutting part of the drill forms a groove from end
to end throughout the entire length of the drill, for the purposes hereinafter
mentioned.
These grooves may be angular, circular or any other suitable shape, but the most
satisfactory results have been obtained when constructed angular, as shown in
Fig. 5. of accompanying drawings.
D, designates a holder formed with prongs or jaws, E, E, the adjacent faces of
which are fitted to correspond with the grooves, C, C, in the drill shank, B.
In the body of holder, D, beyond the jaws or prongs, E, E, the slit, F, may be
formed to permit it to spring, or give a little when the jaws, E, E, are being clamped
to the drill shank, B, by the sleeve, G.
G, is a sleeve, which is screw-threaded a short distance on its inner face at, a¹, to
correspond with a screw-thread, a², on the body of the holder, D.
On the inner face of the sleeve, G, near the outer end, an inclined flange, G¹, is
formed, which is fitted to the bevelled outer end of the pronga or jaws, E, E, so
that when said sleeve, G, is screwed up, this inclined flange binds on the bevelled
outer ends of the prongs or jaws, E, E, and compresses them in the grooves, C, C,
in the drill shank, B, to rigidly and firmly secure the drill, A, in the holder, D.
In Fig. 7. of annexed drawings, the circles, i, i, represent a graduation of different
sized drills, with the angular shape of the jaws or prongs, E, E, of the holder
marked across them, at, n, n, to show that a small, as well as a large size of drill
may be rigidly, securely and firmly held in the same holder.
The inner edges, e¹, of the prongs or jaws, E, E, may be parallel, or they may be
slightly tapering towards the body of the holder, D, for the purpose of allowing
for slight variations in the forming of the grooves in the drill or wood bit shank.
The drill or wood bit, being grooved from end to end, as hereinbefore described,
it yields to the straightener rolls, so that the drill may be accurately sized, and
straightened under one operation, thereby requiring less time and less labor to
manufacture a drill or wood bit; and this Invention is more economical under
the rolling process, than under the process where the drills are milled, and the
shanks turned, for by rolling the grooves in the drill and shank. of same length-
wise, the steel is elongated, so that a drill is constructed from a much less quantity
of material.
The drills rolled and straightened with solid shanks cannot be accurately sized,
without first sizing the solid part of the shank of the drill in a separate roll, as
round bar steel varies in size in cross section, and does not yield or reduce when
rolled transversly or in the direction of its circumference.
The advantage of providing this holder, D, with prongs or jaws, E, E, in combi-
nation with drills, A, or wood bits in which grooves, C, C, are formed, as herein-
before described, is, that at least twice the number of different sized drills may be
held by one of these holders, than can be held by one of any other holder or socket
in present use, and this holder is of extreme small diameter, which is of great
advantage to the mechanical working of the drill in confined positions.
This holder may be attached to a drill press or lathe, by simply turning the
blank end of the holder to fit the spindles of said drill press or lathe.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1st A drill or wood bit shank, B, in which two grooves, C, C, are formed,
throughout its entire length, for the purpose specified.
2nd A drill or wood bit, A, in which two grooves, C, C, are formed, through-
out its entire length, substantially as shown and described and for the purpose
specified.

page_text: 3rd A drill or wood bit shank, B, in which two grooves, C, C, are formed the
metal between the two grooves, C, C, being of one thickness in many different
Bizes of drills, substantially as shown and described and for the purpose set forth.
4th A holder, D, formed with jaws or prongs, E, E, substantially as shown and
described and for the purpose set forth.
3
5th The combination of a drill shank, B, in which grooves, C, C, are formed,
with the holder, D, formed with prongs or jaws, E, E, and sleeve, G, substantially
as shown and described and for the purpose specified.