IMPROVEMENTS IN MANUFACTURING SHEET METAL
Year: 1858

page_text: LETTERS PATENT to Henry William Wimshurst, of 7, Wilmot Road,
Dalston, in the County of Middlesex, Gentleman, for the Invention of
"IMPROVEMENTS IN MANUFACTURING SHEET METAL."
Sealed the 5th November 1858, and dated the 1st July 1858.
PROVISIONAL SPECIFICATION left by the said Henry William Wims-
hurst at the Office of the Commissioners of Patents, with his Petition,
on the 1st July 1858.
I, HENRY WILLIAM WIMSHURST, of 7, Wilmot Road, Dalston, in the
County of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN MANUFACTURING SHEET METAL," to be as
follows:-
The chief object of this Invention is to manufacture sheet metal, for
example, lead and tinfoil, in a more expeditious and economical manner than
heretofore. In the ordinary mode of making sheet metal, either cast pigs of
the metal are subjected to rolling pressure under several pairs of rollers, or
when partially laminated a number of sheets are placed on each other, and
either passed through a pair of rollers whose centres are made gradually to

page_text: converge, or the said number of sheets so placed together are acted upon by
a hammer until-reduced to the required thickness. By my improved process
either a cylinder or block of the metal intended to be formed into sheets is
first cast in a mould and then acted upon by a knife or cutting tool. When
the cylindrical form is adopted the detail may be somewhat as follows:-A
spindle or shaft of iron or other metal is provided, the ends of which are
turned so as to fit truly into bearings or journals. The centre of this spindle
is either fluted or turned, so as to allow of a perfect combination between it and
the metal to be cut into foil or sheets. This spindle is placed in a cylindrical
mould, and the metal cast round it to the desired length and diameter. The
spindle with the metal thereon is then placed in its bearings in a machine some-
what similar to a turning lathe, and made to revolve by steam or other power.
A knife or cutter the length of the cylinder of metal is gradually brought near
to the cylinder by means of wheelwork or some other method (the cutter
being supported on a sliding frame), and a continuous shaving or sheet of the
metal thereby taken from the cylinder until the whole (or nearly so) is
removed from the shaft or spindle.
When the rectangular or block form is adopted, the block of metal may be
placed in the bed of a machine somewhat similar to an ordinary planing
machine, the knife being fixed over the block, and made to descend a certain
fixed distance just before the block of metal is pressed forward past the
cutting edge of the knife, whereby a sheet of the metal the size of the block
is produced at each forward stroke of the machine. If preferred, the knife or
cutter may be made to move and the block remain stationary.
Although I have here described in detail two modes of carrying this
Invention into practice, I do not intend to limit myself to those details, as my
Invention consists in the production of thin sheets of metal by means of any
arrangement of cutters, in place of producing such sheets by means of rolling
or beating mechanism.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry William Wimshurst in the Great Seal Patent Office
on the 1st January 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
WILLIAM WIMSHURST, of 7, Wilmot Road, Dalston, in the County of Middle-
sex, Gentleman, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of July, in the year of our Lord One
thousand eight hundred and fifty-eight, in the twenty-second year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Henry William Wimshurst, Her special license that I, the said Henry
William Wimshurst, my executors, administrators, and assigns, or such
others as I, the said Henry William Wimshurst, my executors, administrators,
or assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and law-
fully might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an Inven-
tion for. "IMPROVEMENTS IN MANUFACTURING SHEET METAL," upon the condition
(amongst others) that I, the said Henry William. Wimshurst, by an instru-
ment in writing under my hand and seal, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great Seal
Patent Office within six calendar months next and immediately after the
date of the said Letters Patent.
• NOW KNOW YE, that I, the said Henry William Wimshurst, do hereby
declare the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawings, and
to the letters and figures marked thereon, that is to say :-
My said Invention relates to the manufacture of sheet metal, as, for
example, lead and tinfoil, in a more expeditious and economical manner than
has heretofore been the case. In the ordinary mode of making sheet metal,
either cast pigs of the metal are subjected to rolling pressure under several
pairs of rollers, or when partially laminated a number of sheets are placed on
each other, and either passed through a pair of rollers whose centres are
made gradually to converge, or the said number of sheets so placed together
are acted upon by a hammer until reduced to the required thickness. By
my improved process, either a cylinder or block of the metal intended to be
formed into sheets is first cast in a mould, and then acted upon by a knife or
cutting tool for its reduction to the sheet or foil form. When the cylindrical
form is primarily adopted, the detail may be somewhat as follows:-A spindle
or shaft of iron or other metal is provided, the ends of which are turned so
as to fit truly into bearings or journals. The centre of this spindle is either
fluted or tinned, so as to allow of a perfect combination between it and the.

page_text: metal to be cut into foil or sheets. This spindle is placed in a cylindrical
mould, and the metal is cast round it to the desired length and diameter.
The spindle with the metal thereon is then placed in its bearings in a machine
somewhat similar to a turning lathe, and made to revolve by steam or other
power. A knife or cutter of the length of the cylinder of metal is gradually
brought near to the cylinder by means of wheelwork or by any other con-
venient means (the cutter being supported on a sliding frame), and a
continuous shaving or sheet of the metal is thereby taken from the cylinder
until the whole of the metal (or nearly so) is removed from the shaft or
spindle.
When the rectangular or block form is adopted, the block of metal may
be placed on the bed of a machine somewhat similar to an ordinary planing
machine, the knife being fixed over the block, and made to descend a certain
fixed distance just before the block of metal is pressed forward past the
cutting edge of the knife, whereby a sheet of the metal of the size of the
block is produced at each forward stroke of the machine. If preferred, the
knife or cutter may be made to move, and the block remain stationary.
Although I have here described in detail two modes of carrying this
Invention into practice, I do not intend to limit the arrangements to those
details, as my Invention essentially consists in the production of sheets of
metal by means of any arrangement of cutters in place of producing such
sheets by means of rolling, or beating, or crushing mechanism.
And in order that my said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose I shall
refer to the several Figures on the Sheet of Drawings hereunto annexed, the
same letters of reference indicating corresponding parts throughout all the
Figures.
Figure 1 of my Drawings represents an end elevation of an arrangement
of my machinery or apparatus for producing sheets of lead, tin, or other
ductile metal or alloy; Figure 2 is a front elevation of the same; and
Figure 3 is an elevation of the opposite end of the machine to that shewn at
Figure 1. A is a cast-iron bed plate having two strong vertical pillow blocks:
B, B, cast on the upper face thereof, which constitute the bearings for the
reception of the metal cylinder C, which is formed with large journals, so as
to enable it to rotate steadily in its bearings. This metal cylinder before
being placed in its bearings has a cylinder of lead D or other ductile metal
intended to be reduced to sheets or foil cast over it in a suitable cylindrical
mould, the supporting metal cylinder being laid carefully in the mould, so as

page_text: to be in a perfectly central position, and therefore concentric with the lead or
other ductile metal cylinder cast round it; or this operation may be per-
formed without removing the cylinder C from its bearings by enclosing it in
a cylindrical metal mould, which is divided in the direction of its axis, and
provided with suitable fastenings for holding it together while the metal is
being cast. A stream of cold water may be allowed to flow through the
centre of the cylinder C during the operation of casting, for the purpose of
cooling the metal from the interior gradually towards the surface or exterior,
whereby a more solid and homogeneous casting is obtained than when such
casting is allowed to cool from the outer or exterior surface towards the
interior. The surface of the supporting cylinder may be fluted, grooved, or
tinned for the better holding of the lead cylinder, and preventing all chance
of its becoming loose on the supporting cylinder. The combined cylinders
are then placed in the machine, as shewn in the Drawings, and the plummer
blocks are tightened up. A slow rotatory motion is imparted to the cylinders
from the driving shaft E, which works in bearings F, F, cast on the side of
the bed plate, and carries a cone driving pulley G and endless worm H, which
latter gears into a corresponding worm wheel I, fast on one end of the sup-
porting cylinder C. In order to prevent back lash, a longitudinal adjustment
of the worm H is effected by the end adjusting screw K. The supporting
cylinder C is extended beyond its bearing at the opposite end to that which
carries the large worm wheel, so as to form a pulley M. This pulley imparts
motion by means of a belt N to a cone pulley O, keyed on to the shaft P,
which works in suitable bearings in the opposite sides of the bed plate, and is
parallel to the axis of the cylinder C. This cone pulley gives motion by
means of a belt Q to the cone pulley R, fast on one end of the shaft S, which
works in bearings T, T, cast on the front side of the bed plate. This shaft
carries an endless screw or worm, which gears into and drives the worm
wheel U, fast on one end of a V-threaded screw spindle V, which works
through a fixed nut in the under side of the slide W, suitable adjustments
being adopted for preventing back lash of the slide W. This slide works
accurately in grooves made for that purpose in the surface of the bed plate,
and it carries the cutting tool X, such tool being so fitted to the slide by
means of slots and screw bolts as to be readily adjusted in its position on the
slide, as will be easily understood on referring to the Drawings. It is obvious
that the rotation of the cylinder C will cause the slide W with its catting.
tool to advance constantly towards the centre of the cylinder, and that the
knife will thereby produce a continuous shaving or sheet. When found

page_text: requisite, a stream of water or other lubricant may be kept flowing over the
cutting tool, but in most cases this will not be necessary. As the cutting
edge extends along the entire length of the metal cylinder D, and is adjusted
so as to be perfectly parallel to the axis of such cylinder, it follows that a
continuous sheet of metal will be turned off from the cylinder D, the thickness
of such sheet depending upon the advance made by the cutting tool during
each revolution of the cylinder under treatment. Thus, by suitably adjusting
the belts N and Q on their respective cone pulleys, the advance of the knife
may be accelerated or retarded, in the first case producing a comparitively
thick sheet or foil, and in the second case a thinner one. The continuous
sheet or foil, as fast as it is cut, is received on to the collecting spindle Y,
which is carried in bearings in the brackets Z, and driven either by the
machine itself or by the attendant. If .found desirable, a pair of friction
drawing rollers may be employed for the purpose of drawing the sheet or
releasing it from contact with the cutting edge of the knife as fast as it is cut
from the cylinder or block, such friction drawing rollers, with the sheet or foil
passing between them, being held together by springs, and actuated by the
machine itself through the intervention of regulating friction gear.
It may here be observed, that although I have illustrated a means of
producing sheet metal or foil by cutting such sheet from a cylinder, to which
a rotatory motion is imparted after the manner of ordinary lathe turning,
I wish it to be distinctly understood that I do not confine or restrict my
Invention to any particular construction or arrangement of machinery or
apparatus for manufacturing sheet metal or foil so long as the essential
feature of my Invention, namely, the use of a knife or cutting tool for such
purpose, in lieu of rolling or beating mechanism, be retained. For example,
sheets of foil may be produced from a rectangular block placed horizontally
on the bed of an ordinary metal planing machine, or placed vertically in a
slotting machine, the knife or cutter being of the same width as the block
operated upon or of the sheet to be produced, whereby a sheet of foil will be
cut or shaved off the block at every stroke of the cutter or traverse of the
block beneath such cutter. It is obvious that the actual cutting motion may
be derived either from moving the cutter or the metal to be cut.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe in conclusion that I do not confine or restrict
myself to the precise details or arrangements which I have had occasion to
describe or refer to, as variations may be made therefrom without deviating

page_text: from the principles or main features of my said Invention; but what I con-
sider to be novel and original, and therefore claim as the Invention secured to
me by the herein-before in part recited Letters Patent is, ―
First, the manufacture or production of sheet metal or metal foil by means
of cutters in lieu of rolling or beating mechanism.
Second, the system or mode of manufacturing or producing sheet metal by
cutting the same from a block or solid mass.
In witness whereof, I, the said Henry William Wimshurst, have here-
unto set my hand and seal, this Thirty-first day of December, One
thousand eight hundred and fifty-eight.
H. W. WIMSHURST. (L.S.)