IMPROVEMENTS IN SEWING MACHINES
Year: 1871

page_text: LETTERS PATENT to Joseph Buchanan Robertson, of Lurgan, in the
County of Armagh, Ireland, Mechanic, for the Invention of
"IMPROVEMENTS IN SEWING MACHINES."
"
Sealed the 8th August 1871, and dated the 19th June 1871.
· PROVISIONAL SPECIFICATION left by the said Joseph Buchanan
Robertson at the Office of the Commissioners of Patents, with his
Petition, on the 19th June 1871.
I, JOSEPH BUCHANAN ROBERTSON, of Lurgan, in the County of
3. Armagh, Ireland, Mechanic, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN SEWING MACHINES," to be as follows:-
:-
"
My Invention consists of improved arrangements of the mechanism
for producing the lateral motion of the needle and shuttle box or part.
of the shuttle box in sewing machines for producing hem stitch work,
such as described in the Specification to my former Letters Patent,
No. 2720, of 1870.
. One of my present improvements consists in connecting the guide
carrying the needle slide and the separate part of the shuttle box in
which the needle works to one and the same cranked or bent arm, to

page_text: which is fixed a second arm having either an adjusting screw kept in
contact with the periphery of the actuating cam by means of a spring, or
having a stud or roller fitting in a groove on the said cam (as described
in my said former Specification), so that by the rotation of such cam
the needle slide and the said part of the shuttle box have the requisite
lateral motion imparted to them by means of the said arm, the guide of
the needle slide being made to swing upon a fixed stud at the upper end
thereof as a centre.
According to another modification, instead of imparting the lateral
motion to a part only of the shuttle box I cause the entire shuttle box
to move laterally together with the needle slide by fixing the shuttle.
box upon a sliding frame having a cranked or bent arm to which the
guide of the needle slide is fixed, the requisite motion being imparted to
the sliding frame by means of a regulating screw carried by an arm
projecting from the frame and kept in contact with the periphery of the
before-mentioned actuating cam by means of a spring. Or the motion
may be imparted by means of a rocking lever, one end of which has a
stud or roller working in a groove on the cam, while the other end has
a stud working in a slot in the sliding frame in a similar manner to the
rocking lever described in my aforesaid former Specification.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Buchanan Robertson in the Great Seal
Patent Office on the 20th November 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
BUCHANAN ROBERTSON, of Lurgan, in the County of Armagh, Ireland, 2
Mechanic, send greeting.
of
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
..Letters Patent, bearing date the Nineteenth day of June, in the year
our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors, '3
give and grant unto me, the said Joseph Buchanan Robertson, Her
special licence that I, the said Joseph Buchanan Robertson, my èxe-
cutors, dministrators, and assigns, or such others as I, the said Joseph
Buchanan Robertson, my executors, administrators, and assigns, should

page_text: 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 Joseph Buchanan Robertson, 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 Buchanan Robertson," do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, reference being had to the.
accompanying Sheet of Drawings, and to the figures and letters marked
thereon, that is to say :-
My Invention consists of improved arrangements of the mechanism
for producing the lateral motion of the needle and shuttle box or part
of the shuttle box in sewing machines for producing hem stitch work,
such as described in the Specification to my former Letters Patent,
No. 2720, of 1870.
One of my present improvements consists in connecting the guide
carrying the needle slide and the separate part of the shuttle box in
which the needle works to one and the same cranked or bent arm, to
which is fixed a second arm having either an adjusting screw kept in
contact with the periphery of the actuating cam by means of a spring,
or having a stud or roller fitting in a groove on the said cam (as
described in my said former Specification), so that by the rotation of
such cam the needle slide and the said part of the shuttle box have the
requisite lateral motion imparted to them by means of the said arm,
the guide of the needle slide being made to swing upon a fixed stud
at the upper end thereof as a centre.
According to another modification, instead of imparting the lateral
motion to a part only of the shuttle box I cause the entire shuttle box

page_text: to move laterally together with the needle slide by fixing the shuttle
box upon a sliding frame having a cranked or bent arm to which the
guide of the needle slide is fixed, the requisite motion being imparted
to the sliding frame by means of a regulating screw carried by an
arm projecting from the frame and kept in contact with the periphery
of the before-mentioned actuating cam by means of a spring. Or the
motion may be imparted by means of a rocking lever, one end of which
has a stud or roller working in a groove on the cam, while the other end
has a stud working in a slot in the sliding frame in a similar manner
to the rocking lever described in my aforesaid former Specification.
On the accompanying Sheet of Drawings are shewn sewing machines
with my before-described improvements applied thereto; only such
parts of the machines are shewn as are necessary for explaining the
nature of my improvements, and those parts which are new or modified
in their construction for the purposes of my present Invention are shewn
in red lines.
Figure 1 shews a side elevation of a sewing machine with the first
herein-before described improvements applied thereto. The guide A of
the needle slide B turns upon a fixed stud C, and is rigidly connected
by a cranked arm D at the front of the framing to the moveable part E¹
of the shuttle box E in which the needle works. To the cranked arm D
is rigidly fixed. a second arm F (situated at the back of the framing).
by means of a pin G passing through a slotted hole formed in the
framing, shewn in dotted lines. The arm F carries an adjustable
screw H, which is kept in contact with the periphery of the actuating
disc cam I by means of the spring J connected to the arm F and to
the framing. Thus by the rotation of the cam I a to-and-fro motion
is imparted to the arm F, which in its turn actuates the arm D so as
to impart the requisite lateral motion to the guide A, needle slide B,
and part of the shuttle box E¹ for causing the needle to produce the
hem stitch. The arm F also carries a regulating screw K, by means of
which the extent of motion of the several parts may be regulated
independently of the cam I by screwing the same so as to come in
contact with the framing at any point of the backward motion of the
arm F. The cam I is fixed on a countershaft L, and is actuated by the
driving gear of the machine in the same manner as the cam b, described
in the Specification to my before-mentioned previous Patent. In place

page_text: of this form of cam may be employed a grooved cam, the arm F being
in that case provided with a roller working in the groove of the cam
in place of the screw H and spring J.
Figure 2 shews a side elevation of a sewing machine with the second
herein-before described improvements applied thereto. In this case the
entire shuttle box E is caused to move to and fro laterally together
with the needle slide B, the guide A being for this purpose fixed
rigidly to the shuttle box by means of the cranked arm D, and it slides
with a slot, shewn in dotted lines, upon a fixed stud C. The shuttle
box is fixed to the part D¹ of the arm D, which part D¹ is provided
with guides D³, D³, sliding upon the guide bar M fixed to the support N.
The needle plate O is fixed to the support N by means of side plates O¹
passing down on either side of the shuttle box. The part D¹ of the
arm D carries at the back an adjustable screw H, which is kept in
contact with the actuating disc cam I by means of the spring J in the
same manner as in the preceeding arrangement, so that by the rotation
of the cam the requisite lateral to-and-fro motion is imparted to the
arm D, shuttle box E, and needle guide A. P is a regulating screw
screwing through the end of D₁, and capable of being brought in contact
with the end of the support N, for the purpose of regulating the extent
of motion of the parts A, D, and E.
Figure 3 shews the same arrangement of shuttle box E, guide A, and
arm D as just described, these parts being in this case actuated by the
grooved cam I and bell-crank lever Q turning upon the pin Q', and
arranged and operating in the same manner as the cam 6 and bell-crank
lever a shewn and described in the Specification to my before-mentioned
previous Patent, the end of the lever Q being made to work in a slot D*
in the arm D as shewn.
Having thus described the nature of my Invention, and in what manner
the same is to be performed, what I claim under the herein-before in
part recited Letters Patent is,--
First. Connecting the guide A to the moveable part of the shuttle
box E by means of the cranked arm D, to which is fixed the arm F,
actuated by a disc cam or grooved cam as herein-before described with
5 reference to Figure 1 of the Drawings.
Second. Causing the entire shuttle box E to partake of the lateral
motion imparted to the guide A by connecting the two parts by means
of a cranked arm D, D¹, actuated by a disc cam or grooved cam, and

page_text: sliding upon a guide bar M, as herein-before described with reference
to Figures 2 and 3 of the Drawings.
In witness whereof, I, the said Joseph Buchanan Robertson, have
hereunto set my hand and seal, this Eighteenth day of Novem-
ber, in the year of our Lord One thousand eight hundred and
seventy-one.