A Hand Tool for Outting Holes in Strong Steel or other Metal Plates.
Year: 1893

page_text: Date of Application, 30th Jan., 1893
Complete Specification Left, 30th Oct., 1893-Accepted, 9th Dec., 1893
PROVISIONAL SPECIFICATION.
A Hand Tool for Outting Holes in Strong Steel or other Metal
Plates.
I BENJAMIN HAIGH Pleasant Villa Plashet Grove East Ham London E.
Coppersmith do hereby declare the nature of this invention to be as follows :—
'It consists of a circular blook of steel or other suitable material and dementions
in which block I provide a recess of required depth the outer part or rim being
sharp edged and the same diameter as the hole to be cut. In the centre of the
said block and recess I fix a stud bolt of aufficient strength which forms a pivot
for a arm or holder to rotate upon. I provide a flanged boss to fit the stood bolt
and on the outor diam. of the said boss I fit a handle or arm which arm rotates on
the outer diam. of the boss a nut on the stud bolt holds the boss tight on a plate
and the plate firm on the circle or block admiting the arm to rotate freely on the
boss on which arm I fix a socket or tool holder at the outer part of the circle to
the same radius as the circle a cuter of steel I fit in the socket which is adjusted
to exactly fit the circle so that when it is operated upon with a hammer and
worked in a rotary form by the handle it cuts a true circle and clean.
Dated this 30th day of January 1893.
COMPLETE SPECIFICATION.
A Hand Tool for Outting Holes in Strong Steel or other Metal
Plates.
I, BENJAMIN Haigh of Pleasant Villa, Plashet Grove, East Ham, London, E.
Plumber, do hereby declare the nature of this invention and in what manner the
samo is to be performed, to be particularly described and ascertained in and by the
the following statement :-
This invention is designed to supply an easy method of cutting out round or
oblong holes or disks in metal or other hard substances.
It consists of a circular or oval block of steel or other suitable material which
may be formed whole or in adjustable sections and may be of any suitable size.
In this block a recess or die, either circular or with circular ends is formed of any
required depth, the inside face of the recess being made with a cutting edge, and
the diameter being the same as that of the hole or disk required to be cut in or
from the sheet of metal. Through the centre of this block a vertical pin or bolt
passes, on which slides a flanged sleeve. Round this sleeve and resting on the
Hange is fitted a horizontal bar on the outer end of which is a handle. One or
more sockets are made in this bar to carry the cutter. The flanged sleeve serves
to keep the sheet of metal in place when being operated upon, and it is tightened
by means of a fly nut on the upper end of the bolt. It will be seen that the
principle of this invention is very simple; namely, an arm carrying a cutter
revolving round a fixed centre pin or pivot, upon a suitable die or base plate.
When the metal has been partly out by hand pressure a hammer may be used
to drive the cutter through the sheet quickly, or any other available pressure may
be used if convenient.
I will now describe the invention with reference to the accompanying drawings
in which

page_text: Fig. 3, shows a front elevation of the cutter or cutting blade only. This blade
in cross section corresponds with the hole or socket e.
Fig. 4, shows a plan view of my cutting tool applied to cutting the curved ends
of oval holes. Two working centres being used instead of one.
Fig. 5, shows half of a sectional elevation of a block constructed to receive
loose annular cutters of different diameters, in order to cut circles of different
sizes.
It will be observed that the cavity o, is flat with a boss p, around the centre bolt
hole. 9 is a loose annular cutter.
Fig. 6, shows a plan view of the bar c, with three centre holes for receiving the 1
centro pivot g, when cutting ringa are employed as in Fig. 5.
o is
a, is the block or base of my apparatus. b, is the sheet of metal to be cut.
the handle bar in which is the socket e, which carries the cutter d. c, is the handle
which may if preferred be crutch shaped or of any preferred form suitable for the
purpose. d, is the cutter or cutting blade formed with a convex face. This may
be formed in some cases with a rovolving wheel cutter if preferred. e, is the
socket for holding the cutter. f, is the recess or die in block a. g, is tho bolt
forming the centro pivot on which the cutter bar works. h, is a sliding sleeve
which by means of a fly nut i, and with or without a washer ', secures the rotating
bar, and keeps the plate of metal in place to be acted ou by the cutter d. i, is:
the fly nut for adjusting the sleeve h." j, is a small screwed pin which passes
through the outer end of the handle-bar c, and serves as a gauge for the cutting
tool. It can be fitted with a wheel or roller if preferred. It also equalises the
pressure on either side of the centre pivot g, and helps to keep the plate level.
k, is a small thumb-bit for operating or adjusting the pin. I, is the head of the
vertical bolt g. m, is the cutting edge of the recess, which with the cutter d,
forms the cutting part or shears of the tool. n, is an auxiliary working centre,
Fig. 4. o, is the bottom of the recess f. p, is a boss in the centre of o, forming a
support to the material being cut. q, is a loose steel ring forming an additional
die or matrix of different diameter to that formed on the block a.
When the machino is to be used as a circular hole cutter the mode of operation
is as follows:—
The sheet of metal or other material b, is perforated to pass over the bolt g, and
is then placed upon the die f; and the sleeve h, and bar c, are put on and
the sleeve is tightened up. by means of the fly nut i, which keeps the whole in
place.
The bar c, is then caused to revolve on the sleeve / round the central pivot g, by
means of the handle o', carrying the cutter d, with it, at a distance from the
'centre corresponding to that of one of the cutting edges m. It thus quickly
effects a cut in the sheet b, and if by reason of the hardness or thickness of the
material operated on, the process is not fast enough any suitable leverage or force
may be applied to the cutter d. For example the head of the cutter may be struck
with a hammer or the bar may be weighted. It will be seen that if the back side
of the cutter d, be made slightly arched or convex, it will describe a clean and true
circle in either direction without excessive friction, but if preferred revolving
culters may be employed.
"
I also prefer to make the face or sharp edge of the cutter convex, but any other
shape can be used, or it may be serrated if desired.
Referring to Fig. 4, this shows a means by which oblong or oval holes may
be out. It consists of employing two sets of my cutting mechanism working
on separato centres, g, n, and on an oblong or oval die base. One of the
centres is placed at each end of the oval dio. Instead of turning the handles
right round they are turned only half round, the half circles thus formed being
concave to each other. When this is done all that is necessary is to cut out the
reuiaining straight line between the ends of the two half circles with a chisel ör
other suitable tool.
It is obvious that on a large base blook other concentric cutting edges may be

page_text: inserted as shewn in Fig. 5, and the cutter bar may have corresponding centre holes
or sockets as shewn in Fig. 6 for adjusting the cutters, so as to cut several sizes of
circles with the same instrument.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what
I claim is :-
1. A circular cutting tool for metal and like purposes, consisting of a block or
base with suitable concavities, furnished with cutting edges or formed with
loose annular cutting rings, a centre pivot and sleeve and one or more rotating
arms carrying cutting blades at regulated distances as herein described and set
forth.
2. In a circular cutting tool the combination of the block a, dief, convex or
wheel cutter d, bar c, with one or more holes r, for centering on bolt g, handle o¹,
and central pivot g, socket e, flanged sleeve h, fly nuts i, k, and pin or guide j, as herein
described and set forth.
3. In a pivotted cutting tool for oblong holes, the combination of a double set
of the mechanism described in Claim 2, working on centres g, n, as and for the
purpose herein described and set forth.
Dated this 30th day of October 1893.
S. 8. BROMHEAD,
97, Newgate Street, London, E.C., Patent Agent.