Improvements in Drills.
Year: 1893

page_text: Date of Application, 22nd Feb., 1893
Complete Specification Left, 9th Nov., 1893-Accepted, 17th Mar., 1894
TROYIDIONAU
Improvements in Drills.
ANDREW KEARNEY, Blacksmith 104 Church Street, Walker-on-Tyne STEPHEN
GALL, Butcher Lamb Street, Walker-on-Tyne, HENRY SAYER, Ironfounder The
Willows Walker-on-Tyne do hereby declare the nature of this invention to be as
follows:-
:-
A tool or drill for drilling holes of any practicable size in any metal. This tool
consists of a round piece of steel or other suitable form or material, with four lips
or cutting edges, which are set at right angles. The two inner edges are in advance
or leading & take about half the cut. I claim by a tool made on this principle to
cut 50% more than the ordinary drill now in use, with the same power & velocity
of cutting edges. It will also drill a perfectly true & parallel hole which does not
require riming.
D
Wao1902
ANDREW KEARNEY.
HENRY SAYER.
STEPHEN GALL.
Improvements in Drills.
ANDREW KEARNEY, 104 Church Street, Walker-on-Tyne, Northumberland,
Blacksmith STEPHEN GALL Butcher Lamb Street Walker-on-Tyne, and HENRY
SAYER, Ironfounder The Willows Walker-on-Tyne do hereby declare the nature
of this invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
A tool or drill for drilling holes of any practicable size in any metals. This
drill is of a spiral form D. with the cutting edges or blades A and B set at right
angles.
The outer part of the spiral D is grooved at intervals, which act as a ryhmer C,
thus finishing the hole complete as the drill passes through.
It must be observed that the grooves C on the outer part of the spiral D do not
extend to the leading edge, thus preventing the outer cutting edge B or blade
coming in contact with the grooves C. at any time when undergoing the process of
grinding, which can be continued so long as any part of the spiral D remains for
clearance E; the back outer edge of the spiral D is rounded so as to prevent the
cuttings when passing up the clearance part E of the drill, from coming in contact
with the ryhmering C. or grooved part of the drill.
This tool or drill can be ground on any ordinary grindstone, (without the aid of
a machine) by grinding the outer blades B first until they come in contact with the
cutting edges of the inner blades A, the inner blades A are then ground to a sharp
cutting edge, with a little less angle than the outer blades B, thus giving the inner
blades A, a slight lead of the outer blades B, and bringing the cutting edges A
and B at right angles with each other, also forming a true centre at the same
time.
By the use of this drill, a machine will last longer and can be made, considerably
lighter owing to the cutting edges or blades A and B being subdivided into 4 sections
and running in a perfectly true centre, which prevents any swerveing to and fro of

page_text: the vertical spindle of the machine, in which the drill is fixed, it can also be run at
a much higher speed, as the construction of the drill is so that a great percentage
of friction in cutting is taken away by the use of four blades A & B, and further
that the cuttings from these blades A. B pass freely up the clearance part C of the
spiral D, each in one piece which prevents any choking, & heating as is the case
with other drills now in use.
This drill can also be used in ratchet braces or any other requisite form where
hand labour is required, and will drill a hole much easier and quicker than
ordinary drills, thus saving a great amount of time & manual exertion at present
required.
The drawing shows a " drill at 2 inch spiral pitch F, which can be made or set
to any pitch to suit the nature of the metal it may be required to cut.
Having now particularly described and ascertained the nature of my said inven-
tion and in which manner the same is to be performed, I declare that which I
claim is
A spiral drill D with the four cutting blades A & B, set at right angles as per
drawing herewith.
Dated this 10th day of March 1894
ANDREW KEARNEY.