CERTAIN IMPROVEMENTS IN SEWING MACHINES
Year: 1863

page_text: LETTERS PATENT to Joseph Coignard, of Nantes, in the Empire of France,
Watchmaker, for the Invention of "CERTAIN IMPROVEMENTS IN SEWING
MACHINES."
Sealed the 18th September 1863, and dated the 20th May 1863.
PROVISIONAL SPECIFICATION left by the said Joseph Coignard at the
Office of the Commissioners of Patents, with his Petition, on the 20th
May 1863.
I, JOSEPH COIGNARD, of Nantes, in the Empire of France, Watchmaker,
do hereby declare the nature of the said Invention for "CERTAIN IMPROVEMENTS
IN SEWING MACHINES," to be as follows, that is to say:-
My improvements in sewing machines consist in preventing the imperfect
tension of the shuttle which produces an irregular and unsound seam. This
want of solidity in the seam is caused by the alteration the thread undergoes
when passing through the several guide holes or under the pressure of a
spring; for in both cases it is greatly weakened and reduced either by the
sharp or angular edges of the holes or by the spring, and as the thread coming
from the shuttle is in the work, the warp supporting the stitch, its deterioration
renders the seam very weak and unsound.
By my Invention the tension of the thread fed by the shuttle is very smooth
and regular, all jerks are done away with and consequently the seam is
perfectly secured and sound. I wind up the thread on the bobbin of the
shuttle as usual, and it passes round a polished steel pressure roller which is

page_text: maintained in its proper place by a screw, and egresses to get into the work
by means of a ring. By such simple contrivance I obtain a regular and
perfect tension of the thread, which not being subjected to sudden jerks of the
machine never breaks, and a regular and sound seam is obtained throughout
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Josoph Coignard in the Great Seal Patent Office on the
11th November 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JosErn
COIGNARD, of Nantes, in the Empire of France, Watchmaker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Iler Letters
Patent, bearing date the Twentieth day of May, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-sixth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Joseph Coignard, Iler special licence that I, the said Joseph Coignard,
I, the said
my executors, administrators, and assigns, or such others as
Joseph Coignard, 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 "CERTAIN IMPROVEMENTS
IN SEWING MACHINES," upon the condition (amongst others) that I, the said
Joseph Coignard, 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 Joseph Coignard, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawing hereto annexed and to the
figures and letters marked thereon, that is to say:--
Machine sewing, to be strong and perfect in all respects, requires a mathe-
matical regularity in the tension of the thread, an imperfect tension producing
an unsound scam. It should be without stiffness and not too clastic, and should

page_text: vary according to the material to be worked, all friction being particularly
avoided as it wears out the thread, so also all sudden jerks which break it
should be prevented.
The object of my Invention is to obviate the imperfect tension of the thread
of the shuttle and is applicable to all sewing machines working with shuttles.
I place in the interior of the shuttle a polished steel roller B set horizontally;
one extremity of the roller is furnished with a spring A acting as a hinge,
the other end is held by means of the screw C having the head of the shape
shewn in the Drawing. It is merely necessary to turn the screw for causing
the roller to take a vertical position in order that the thread which is to form
the seam may be wound over it once, twice, or more according to the kind of
stuff to be sewn. The tension roller B is fed in a direct manner from the
bobbin F with the thread serving as the warp supporting the stitch. The
thread after making a circuit on the roller B, varying in length, passes through
the ring D, which is perfectly polished to prevent any injury to the thread
which passes out through the eye E, to be received on the work. The
piston H maintains the bobbin in its proper position, and forms but one piece
with the spiral spring J and is held by the screw I. By this arrangement
the position of the piston H or of its spring J may be easily altered without
removing the top of the shuttle. The heel G is moveable instead of being
soldered to the shuttle as hitherto; it is held by a screw having its head
placed externally on the frame of the shuttle. To keep it steady and to
prevent it deviating from its place it is provided with two small metallic steady
pins serving as marks, and which penetrate into the body of the shuttle.
The heel G can be replaced at will.
By my improvements the thickest vegetable or animal fabrics can be sewn
without missing the stitch. The thread is no longer weakened or deteriorated
by passing over the sharp angles of the guide holes. It arrives at the seam
unimpared, the sudden jerks arising from an irregular tension being entirely
avoided.
Having thus described the nature of my Invention and the manner in
which the same is or may be carried into effect, I wish it to be distinctly.
understood that I do not confine myself to the precise details herein described,
nor do I confine myself to the precise form or shape of parts herein laid
down, but what I claim as new and desire to be secured by the herein-before
in part recited Letters Patent is,―
First, the mode of removing and replacing the heel G, as herein described
and shewn in the Drawing.

page_text: Secondly, the peculiar construction and arrangement of tension roller B,
as herein described and shewn in the Drawing.
Thirdly, the arrangements of piston H, spring J, and screw I, as hercin-
before described and shewn in the Drawing.
Fourthly, the employment of the ring D through which the thread passos,
as herein-before described and shewn in the Drawing.
In witness whereof, I, the said Joseph Coignard, have hereunto set my
hand and seal, this Twentieth day of October, in the year of our
Lord One thousand eight hundred and sixty-three.