IMPROVEMENTS IN THE MANUFACTURE
Year: 1867

page_text: LETTERS PATENT to Henry Patterson Boyd, of Low Walker, near
Newcastle-on-Tyne, in the County of Northumberland, Bolt Manu-
facturer, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF
Sealed the 11th October 1867, and dated the 12th April 1867.
PROVISIONAL SPECIFICATION left by the said Henry Patterson Boyd
at the Office of the Commissioners of Patents, with his Petition, on the
12th April 1867.
1, HENRY PATTERSON BOYD, of Low Walker, near Newcastle-on-Tyne, in
the County of Northumberland, Bolt Manufacturer, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF
SCREWS, CHIEPLY APPLICABLE FOR FIXING ARMOUR PLATES," to be as follows:-
This Invention relates to certain improvements in the manufacture of
screws, chiefly applicable to the purpose of securing or fixing armour plates
to vessels, batteries, or targets. I propose to make screws by means of a
hammer and dies instead of turning, cutting, or chasing them as ordinarily
done. I prepare suitable dies, according to the pitch and form of the screw
thread, and hammer the metal into the requisite shape, the screw is thus

page_text: formed by compression or by hammering alone, whereby the quality of the
iron or other metal is materially improved and the screws are rendered
especially applicable for fixing armour plates. They may be made of any
length and diameter according to the dimensions of the dies by which they are
formed.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Patterson Boyd in the Great Scal Patent Office
on the 12th October 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
PATTERSON BOYD, of Low Walker, near Newcastle-on-Tyne, in the County
of Northumberland, Bolt Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of April, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirtieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Henry Patterson Boyd, Her special licence that I, the said Henry Patterson
Boyd, my executors, administrators, and assigns, or such others as I, the
said Henry Patterson Boyd, my executors, administrators, and 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 lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF SCREWS, CHIEFLY APPLICABLE FOR
FIXING ARMOUR PLATES," upon the condition (amongst others) that I, the said
Henry Patterson Boyd, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, 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 Patterson Boyd, 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 :-
My Invention relates to certain improvements in the manufacture of
screws, which are chiefly applicable to the purpose of securing or fixing

page_text: armour plates to vessels, batteries, or targets, but which are also applicable to
all general purposes where wood and iron are combined, or for woodwork only.
I propose to manufacture screws by means of bammers and dies instead of
turning, cutting, or chasing them as ordinarily done. I prepare suitable dies
according to the pitch and form of the screw thread, and hammer the. metal
into the requisite shape; the screw is thus formed by compression or by
hammering alone, whereby the quality of the iron or other metal is materially
improved and strengthened, and the screws are rendered especially applicable
for fixing armour plates as well as for other general useful purposes. The
screws may be made of any length and diameter according to the dimensions
of the dies by which they are formed.
In order to carry my Invention into practical effect I first pass the heated
iron (or other metal or alloy, such as steel and copper or other metal suitable
for application to composite ships) through a die having a longitudinal section
with circular or bead sinkings, into which the iron is forced and thus prepared
for forming the thread of the screw; the distance between the centres of the
hollows (assuming that the threads of the screws are to be fixed to the size of
their diameter apart) must be one-fifth closer than the finished size or space
from centres to allow for elongation. The second die must have its section
more nearly resembling the reverse of the screw, with the centre of its sinking
corresponding to the thread one-tenth closer; and the third die must be the
exact counterpart or reverse of the finished screw. The projection of the
thread from the circumference of the screw may be one-fifth or more of its
diameter. The screws thus manufactured are much superior to ordinary
screws, securing a much firmer hold of the wood when screwed in, and
bearing a much greater strain.
In the Drawings annexed, Fig. 1 represents a plan of the first die with a
round or beaded sinking, and Fig. 2 is a section of the same; Fig. 3 is a
plan of the second die with a sharper line of sinking, and Fig. 4 is a section
thereof; Fig. 5 is a plan of the third die, the counterpart of the screw, a plan
of part of which is shewn in Fig. 6; Fig. 7 being a section of the die. Of
course the forms or shapes of the threads may be varied according to the
purpose for which the screw is required; the above are only examples
to shew the principle of the manufacture. The metal passes through the
three stages in order to be perfected with the proper sharpness or outline
by degrees, it not being possible to perfect the screw by the use of one
die only.
Fig. 8 represents a screw as perfected by the last process, and it will be
observed that the threads of the screw are closer than its diameter.

page_text: Having now described the nature of my said Invention and the manner in
which the same is to be performed, I would remark that I do not limit myself
to the exact detail or configuration of parts which I have expressed and shewn,
as the same may obviously be varied or modified without in any degree
departing from the principles on which my Invention is based; for example,
any size or diameter of screw or any form of thread may be made according to
this Invention, but what I claim and desire to be secured to me by the herein
in part recited Letters Patent are, the improvements in the manufacture of
screws for various useful purposes by means of hammers and dies instead of
turning, cutting, or chasing such screws, substantially in the manner herein
specified and illustrated by the Drawings annexed.
In witness whereof, I, the said Henry Patterson Boyd, have hereunto
set my hand and seal, this Second day of October, in the year of our
Lord One thousand eight hundred and sixty-seven.
Witness,
J. WIGHAM RICHARDSON,
Iron Shipbuilder,
Low Walker.
HENRY P. BOYD. (L.s.)