IMPROVEMENTS IN SEWING MACHINES
Year: 1872

page_text: LETTERS PATENT to John Chenhall, of Totness, in the County of
Devon, for the Invention of "IMPROVEMENTS IN SEWING MACHINES,”
PROVISIONAL SPECIFICATION left by the said John Chenhall at the
Office of the Commissioners of Patents, with his Petition, on the
2nd July 1872.
I, JOHN OHENHALL, of Totness, in the County of Devon, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN SEWING
MACHINES," to be as follows:
-
The chief objects of this Invention are the production of sewing
machines, simple in construction, cheap to manufacture, but in the
event of their getting out of order easy to repair, because all the parts,
except the looper, are visible. It is a single thread machine. The body
of the machine is of cast iron screwed to a bed plate. Motion is given
to the driving wheel by handle, which is transmitted by friction to a
pulley on one end of a horizontal shaft. The horizontal shaft, to which
rotary motion is communicated, passes through holes at one end of the

page_text: cast-iron body of the machine, while at the other end it carries a crank
disc, which drives a connecting rod jointed to the top of the needle bar.
There is an incline plane on the needle bar, and a corresponding incline
on the feed bar, which coming in contact at regulated intervals lift the
feed bar forwards. A spring compresses the foot when required to lift the
work forward.
The tension and reel bracket is provided with a pin, which when the
work is lifted forward the length of a stitch comes in contact with the
lever for lifting the foot, thus lifting it off free from the work, and
a spring on the feed bar throws the feed back into its place again
ready for lifting the work for the next stitch, the length of which can
be altered by a feed screw; to make the stitch longer the screw is drawn
back; to make it shorter it is pressed forwards. The looper spindle is
driven by india-rubber band from a pulley on the needle bar driving
spindles.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Ohenhall in the Great Seal Patent Office on
the 2nd January 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
CHENHALL, of Totness, in the County of Devon, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria," by Her
Letters Patent, bearing date the Second day of July, in the year of
our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John Chenhall, Her special licence that I;
the said John Ohenhall, my executors, administrators, and assigns, or such
others as I, the said John Chenhall, 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 SEWING MACHINES," upon
the condition (amongst others) that I, the said John Chenhall, my
executors or administrators, by an instrument in writing under my,
or their, or one of their hands and seals, should particularly describe and

page_text: 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 John Chenhall, 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 of reference marked thereon, that is to say :-
The chief objects of this Invention are the production of sewing
machines, simple in construction and cheap to manufacture, but in the
event of their getting out of order easy to repair, because all the parts,
except the looper, are visible. It is a single thread machine. The body
of the machine is of cast iron screwed to a bed plate. Motion is given
to the driving wheel by handle, which is transmitted to a horziontal
shaft. The horizontal shaft, to which rotary motion is communicated,
passes through holes at one end of the cast-iron body of the machine,
while at the other end it carries a crank disc, which drives a connecting
rod jointed to the top of the needle bar. There is an incline plane on
the needle bar, and a corresponding incline or its equivalent on the feed
bar, for example, a roller, which coming in contact at regulated inter-
vals lift the feed bar forwards. A spring presses the foot when required
to lift the work forward.
The tension and reel bracket is provided with a pin, which when the
work is lifted forward the length of a stitch comes in contact with the
lever for lifting the foot, thus lifting it off free from the work, and the
spring on the feed bar throws the feed back into its place again ready
for lifting the work for the next stitch, the length of which can be
altered by a feed screw; to make the stitch longer the screw is drawn
back; to make it shorter it is pressed forwards. The looper spindle is
driven by an eccentric and rod from a dise on the needle bar driving
spindle.
Figure 1 of the accompanying Drawings is a side elevation of a
machine constructed according to my Invention; Figure 2 is an end
view of the same.
a is the body of the machine; b, the bed plate; a is the driving
wheel; d, horizontal shaft, to which motion is communicated from the.

page_text: driving wheel c, either direct, as here shewn, or by suitable and well-
known gearing; e is the needle bar, driven as shown; f is roller on
same; is the feed bar, and g¹ is the incline plane on it (or vice versa),
against which the roller fworks to lift the feed bar forwards, or two
inclines are used, as shown at Fig. 3, one on the feed bar g, the other
on the needle bar e; h is the spring for pressing the foot on the work.
I prefer to make the foot of the shape shewn, in order to provide as
much room as possible for putting in the needle, and for adjusting the
work; is a guide for the needle bar passing from the reel bracket
through a hole in the body of the machine; k is the reel bracket; 1 is
the feed screw for regulating the length of stitch; the needle is inserted
in a small tube at the bottom of the needle bar, having a hole corre-
sponding with that in the needle bar; both needle and hole have each a
flat side, so that the needle cannot be inserted the wrong way. The
tightening screw passes through a hole in the side of the tube, which
keeps it fastened on to the bottom of the needle bar, and the same screw
bears on the flat side of the needle, which keeps them tight and firm
together; m is the pin on the reel bracket k, which in its descent comes
in contact with and operates the lever o on the feed bar, thus lifting its
foot off from the fabric; p is the looper, being the only part which is
on the under side of the machine; q is the eccentric for giving motion
to bottom bar and looper.
The action is as follows:-The roller flifts the feed bar g forward by
coming in contact with the incline plane g¹ thereon; the spring ŉ com-
presses the foot against the work; the pin m on bracket & descends and
comes at each stitch in contact with the lever o to lift it from the work;
the spring then draws the feed bar back into its original position ready
for the next stitch, and so on.
Having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that I do not limit myself
to the precise details or exact arrangements of the parts of the machine
herein-before described, as the same may be varied or modified to some
extent without departing from the essential features of the Invention ;
but I claim, —
Firstly. The general construction, arrangement, and method of action
of the parts of sewing machines, whereby all the working parts, except
the looper and parts connected therewith, are exposed to the view of the
operator, all substantially as shewn and described.

page_text: JOHN CHENHALL. (L.S.)