IMPROVEMENTS IN THE MANUFACTURE OF PLATES FOR DRAWING WIRE
Year: 1880

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
'IMPROVEMENTS IN THE MANUFACTURE OF PLATES FOR DRAWING WIRE."
A communication from abroad by Charles Dake Rogers, of Providence, Rhode
Island, United States of America.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 5th April 1880.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN THE MANUFACTURE OF
PLATES FOR DRAWING WIRE." A communication from abroad by Charles Dake
Rogers, of Providence, Rhode Island, United States of America.
A draw-plate of the common or ordinary form consists of a flat rectangular plate
of steel or chilled iron which has a series of holes of different gauge. These holes
soon become worn from use, and it is necessary to contract them to secure the
desired diameters or gauges. The operation of reducing the diameter of the holes
is a difficult one and can be performed only by skilled workmen of long experience.
It consists in haminering the plate in a series of concentric-rings, or in a helical line
around the hole, in such a manner as gradually to draw the metal inward toward
the centre of the hole and thereby contract it and temper the plate. The same
method is also adopted in securing the desired gauge of holes in a new plate.
The present Invention consists partly in giving to the plate a peculiar form,
which may be that of a truncated pyramid having many sides, a frustum of a cone,
a hemisphere, or a sphere, the plate being provided with a single hole through its
central longitudinal axis. The said Invention also consists partly in the means by
which a plate of any of these forms may be condensed so as to impart the necessary
temper to the metal and incidentally contract or bring to the right gauge the
The said Invention
diameter of the hole through which the wire is to be drawn.
therefore comprises an article which is the product of a process which inheres in
the manufacture and constitutes an element of the Invention.
In the accompanying Drawing,-
Figures 1, 3, and 5, represent central vertical sections of dies and followers with
draw-plate therein before being compressed, and
Figures 2, 4, and 6, represent in perspective draw-plates of various forms illus-
trative of this Invention.
In the manufacture of draw-plates by my improved method a properly shaped
die and follower are secured in any suitable press, and pressure is applied to the
draw plate in a direction radial to the longitudinal axis of the hole in the plate, as

page_text: shewn in Figure 1, or in the direction of the longitudinal axis of the hole, as shewn
in Figures 3 and 5.
The forms of draw-plates which I consider preferable are a frustum of a cone A,
Figures 1, 2, 3, and 4, a hemisphere B, Figures 1 and 2, or a sphere C, Figures
5 and 6, although a frustum of a pyramid having many sides, and other solids
having the geometrical characteristics of those above mentioned may be used.
These draw-plates are made of steel, and are brought to proper shape by hand or
machine-forging, or both. A hole is then drilled of larger diameter than the gauge
required in the finished plate, and the greater portion of the said hole is reamed
out, as shewn in the sectional views.
When the plates in any of the forms shewn or described, or in the form of a short
cylinder, are to be treated by pressure applied in a direction radial to the longitu-
dinal axis of the hole the die D and follower E are each properly cupped to receive
and act upon nearly one half of the plate, as shewn in Figure 1. The plate is placed
in the die, and pressure being applied through the follower the metal is compressed
toward the axis of the hole, and the diameter of the hole is consequently reduced.
The plate is then turned on its axis in the die ninety degrees (more or less), and
the operation of compressing it is repeated. After the plate has been subjected to
such compressing operation between the dies a sufficient number of times to fully
condense the metal (and it is to be turned as many times and to such extent each
time as may be necessary to cause the whole metal to be equally condensed and
thereby tempered), it is removed from the die and a punch is driven into the hole,
as is usual in the manufacture of draw-plates by other processes, to ensure the exact
required size of the hole.
The desired compression of the metal, and consequent contraction of the holo in
the draw-plate, may also be obtained by applying pressure in the direction of the
longitudinal axis of the hole in the draw-plate in case the surface of the die is
inclined to the axis, as in the case of the frustum of a conc, or of a pyramid, as
shewn in Figure 3; or in case it is curved with reference to the axis, as in the case
of a sphere, as shewn in Figure 5. When any form of draw-plate specified other
than spherical is to be treated by pressure in this direction the die D is cupped .to
a depth nearly equal to the thickness of the plate, and a follower having a plain
face is used, as shewn in Figure 3.
From the foregoing description it will be readily seen that by my improved
method of manufacturing draw-plates for making wire I am enabled to dispense
with the skilled labor heretofore necessary in making said plates, and can there-
fore produce a draw-plate at less expenso than has heretofore attended their
manufacture.
Having thus fully described the said Invention, as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim,
First. In the manufacture of draw-plates the improvement which consists in first
forming the draw-plate into a shape substantially as described, and then subjecting
the said plate to the action of properly shaped swaging dies to condense and temper
the same, as herein set forth.
Second. A draw-plate of a shape substantially as described, and condensed and
tempered by the process of swaging between dies, as above specified.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Fifth day of April, in the year of our Lord One
thousand eight hundred and eighty.