IMPROVEMENTS IN SEWING MACHINES
Year: 1854

page_text: LETTERS PATENT to William Darling, of Edinburgh, Scotland, Merchant,
for the Invention of "IMPROVEMENTS IN SEWING MACHINES."-A communi-
cation.
Sealed the 7th April 1854, and dated the 23rd January 1854.
PROVISIONAL SPECIFICATION left by the said William Darling at the
Office of the Commissioners of Patents, with his Petition, on the 23rd
January 1854.
I, WILLIAM DARLING, of Edinburgh, Scotland, Merchant, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN SEWING MACHINES
be as follows:-
The Invention consists in the general combination and arrangement of the
following portions of mechanism by which the operation of sewing may be
carried on.
The machine formed of such parts in combination consists essentially of a
main shaft in the front part of the machine, suitably mounted and driven
by means of band pulleys from a crank shaft turned by a treadle & fly wheel,
similar to a lathe. On this inain shaft are fixed two excentrics, one on each
side of the driving pulley. On the end of the said shaft is mounted a circular
shuttle suitably formed to receive a circular metallic bobbin, and with an
opening through which the thread may pass from the bobbin. This bobbin is
kept in its place by means of a ring mounted on a kind of bracket through a
part of which a set screw is passed.

page_text: There is also another shaft at the hinder part of the machine suitably
mounted in bearings fixed to the same table or platform to which the main
shaft is mounted. On the hinder shaft is fixed a piece of metal extending
downwards, and at its lower extremity hinged or jointed to a rod connected
with one of the excentrics on the main shaft, from which excentric the rod.
receives a backward and forward motion, and a slight revolving motion is com-
municated to the said hinder shaft through the said piece of metal. To this
latter shaft is also fixed the needle bar which extends so far as to bring the
part wherein the needle is fixed exactly over the centre of the circular shuttle
before mentioned. This needle bar has a kind of tail which extends behind
this shaft and carries on its end a bobbin to supply the needle with thread,
which is kept in proper tension by means of a spring extending along the side
of the said tail. The form of the needle is curved to suit the are described by
the motion of the bar on its axis.
There is also another bar fixed to an upright between the rod and bar above
referred to. This latter bar has on its front end a kind of foot which is made
to press upon the cloth, and being acted upon by a spiral spring, allows the
cloth to be moved forward at each stitch. The cloth is carried forward, as
required, by means of a slide & spring acted upon by one of the excentrics on
the front or main shaft of the machine, in such a manner as to give a back-
ward and forward motion to the slide and an up and down motion to the
spring. "
The cloth is laid upon a small platform at the front part of the machine, in
which is formed an opening for the needle to pass through, also a slit or
opening for getting out the thread, and also another slit or opening for the
sharp points on the cloth feeder or slide to pass through; under this platform
at one side is fixed a snail wheel for regulating the length of the stitch, and on.
the other side there are two springs for preventing the threads from getting
out of their proper places; connected with the driving crank shaft, and driven
therefrom by pulleys, there is a spooling apparatus containing a spindle,
with two ends of different sizes, on the smaller end of which is fixed the
circular bobbin for the shuttle, and on the larger end the bobbin intended
to supply the needle.