Iм- PROVEMENTS IN SEWING MACHINES
Year: 1869

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Gentleman, for the Invention of "Iм-
PROVEMENTS IN SEWING MACHINES." -A communication from abroad by
Leonard Erni, of Zurich, Switzerland, Machinist.
Sealed the 14th January 1870, and dated the 19th July 1869.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition,
on the 19th July 1869.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN SEWING MACHINES," a communication from
abroad by Leonard Erni, of Zurich, Switzerland, Machinist, to be as
follows:-
This Invention relates more particularly to what are known as shuttle
machines, although certain parts of the improvements herein-after
referred to are equally applicable to other kinds of sewing machines.

page_text: The improvements consist, 1stly, of a peculiar combination of
mechanism for actuating the roughened or serrated plate of what is
known as the under "four motion feed."
2ndly. Of a mode of varying or adjusting the height of the feeding
surface above the cloth plate.
3rdly. Of a peculiar arrangement for regulating the length of stitch,
whereby a greater range in the length of stitch capable of being
produced in the same machine is obtained.
4thly. Of a peculiar combination and arrangement of mechanism for
actuating the shuttle carrier.
The upper part of the machine is by preference constructed on the
Singer type.
Near the rear end of the driving shaft there is fitted a cam or
wiper, which operates upon a friction bowl on the upper end of a
vertical lever of the first order, the lower end of such lever imparting
motion by simple contact alone to a horizontal slotted lever working on
a fulcrum in the under side of the base plate of the machine. An
adjustable screw, capable of being tightened or set by a thumb nut,
enters the slotted part of the horizontal lever, and engages also with a
corresponding slot in a second horizontal lever, which projects some
distance over the first horizontal lever, and works on a fulcrum at its
front end; this second horizontal lever is kept in constant contact with
the rear end of the feed bar by the tension of a helical spring, and
imparts the forward or feed motion to such bar. The back or return
stroke of the feed bar is derived from a helical spring. By shifting the
screw along the slots in the horizontal levers the throw of the feed bar
will be increased or diminished, thus producing longer or shorter stitches
as required. The upward or vertical movement of the feed bar is derived
from a segmental cam fast on a rocking shaft below the base plate, such
shaft deriving its motion from the upper or driving shaft by an eccentric
keyed on the driving shaft and actuating an eccentric rod, which is
jointed to a lever arm projecting from one side of the rocking shaft.
The under side of the feed bar is inclined, and a friction bowl carried by
an adjustable slide on a lever beneath the feed bar transmits the vertical
movement to such feed bar, the said leyer being operated upon directly
by the segmental rocking cam. By moving the adjustable slide along
its lever the feed bar may be more or less elevated above the cloth plate
to suit the nature of the fabric operated upon. A tightening screw

page_text: serves to fix the slide after it has been adjusted in its proper position..
The same rocking shaft which carries the segmental cam for imparting
the vertical reciprocating motion to the feed bar serves also to actuate
the shuttle, which is contained in a vibrating arm or shuttle carrier fast
on the rocking shaft
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 19th January 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middle-
sex, Gentleman, send grecting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of July, in the year of
our Lord One thousand eight hundred and sixty-nine, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said John Henry Johnson, Her special license that
I, the said John Henry Johnson, my executors, administrators, and
assigns, or such others as I, the said John Henry Johnson, my exe-
cutors, administrators, or 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," a communication from abroad by Leonard Erni, of
Zurich, Switzerland, Machinist, upon the condition (amongst, otliers)
that I, the said John Henry Johnson, my executors or administrators;
by an instrument in writing under my hand and seal, 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 John Henry Johnson,, 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, roference being had to the accompanying

page_text: Drawings, and to the letters and figures marked thereon, that is to
say:-
The said Invention has reference more particularly to the feed motion
of sewing machines, and consists, firstly, of a peculiar combination of
mechanism for actuating the feed bar of what is known as the under
"four motion feed."
Secondly. Of a peculiar arrangement for regulating the horizontal
throw of the feeding surface, whereby a greater range in the length of
stitch capable of being produced in the same machine is obtained.
Thirdly. Of an arrangement for varying or adjusting the height of the
feeding surface above the cloth plate, or, in other words, of varying the
extent of its vertical throw.
Near the rear end of the driving shaft, which is carried in the fixed
arm or bracket, as in the "Singer" type of sewing machine, there is
fitted a cam or wiper, which operates upon a friction bowl on the upper
end of a vertical lever of the first order, the lower end of such lever
imparting motion by simple contact alone to a horizontal slotted
lever working on a fulcrum on the under side of the base plate of the
machine. An adjustable screw, capable of being tightened or set by a
thumb nut, enters the slotted part of the horizontal lever, and engages
also with a corresponding slot in a second horizontal lever, which
projects some distance over the first horizontal lever, and works on a
'fulcrum at its front end; this second horizontal lever is kept in constant
contact with the rear end of the feed bar by the tension of a helical
or other spring, and imparts the forward or feed motion to such bar.
The back or return stroke of the feed bar is also derived from a helical or
other spring. By shifting the screw along the slots in the horizontal
levers the throw of the feed bar will be increased or diminished, thus
producing longer or shorter stitches, as required. The upward or vertical
movement of the feed bar is derived from a segmental cam fast on a
rocking shaft below the base plate, such shaft deriving its motion from
the upper or driving shaft by an eccentric keyed on the driving shaft,
and actuating an eccentric rod, which is jointed to a lever arm pro-
jecting from one side of the rocking shaft. The under side of the feed
bar is inclined and a friction bowl carried by an adjustable slide on a
lever beneath the feed bar transmits the vertical movement to such.feed
bar, the said lever being operated upon directly by the segmental rocking.
cam. By moving the adjustable slide along its lever the feed bar may be

page_text: more or less elevated above the cloth plate to suit the nature of the fabric
operated upon. A tightening screw serves to fix the slide after it has
been adjusted in its proper position. The same rocking shaft which
carries the segmental cam for imparting the vertical reciprocating motion
to the feed bar may, if desired, be employed also to actuate the shuttle,
which in that case may be carried on a vibrating arm or shuttle carrier
fast on the said rocking shaft.
And in order that the said Invention may be fully understood I shall
now proceed more particularly to describe the same, and for that purpose
shal refer to the several Figures on the annexed Sheet of Drawings,
the same letters of reference indicating corresponding parts in all the
Figures.
Figure 1 of the Drawings represents a side elevation of one type of
sewing machine with the said improvements applied thereto; Figure 2
is a plan of the under side of the table or bed plate shewing the
mechanism carried thereby; Figure 3 is a transverse vertical section
of the front end of the machine taken along the line 1-2, in Figure 1;
and Figure 4 is a similar view of the driving end of the machine taken
along the line 3, 4, in Figure 1.
•
A is the bed plate of a sewing machine constructed on what is known
in the trade as the "Singer" type; B is the hollow overhanging arm or
bracket, within which rotates in suitable bearings the driving shaft C,
which transmits motion in the well known manner to the needle bar D.
Towards the rear end of the driving shaft there is fitted on to or formed
in one piece therewith an eccentric E, which drives an eccentric rod F,
the lower end of such rod being jointed to a short arm G fixed on
the rocking shaft H; this rocking shaft works between conical stud
centres I, I, screwed into the lugs K, K, and, if desired, may carry a
vertical oscillating shuttle carrier or driver L; but I do not claim such
a driver as forming any part of the said present Invention. Near to the
front end of the rocking shaft H there is fitted a segmental rocking
cam M, the surface or periphery of which has a projection or incline
formed thereon, as shown in Figure 3. The object of this cam will be
herein-after fully explained. By the side of the eccentric E on the
driving shaft C there is also secured a cam or wiper N, which on rotating
strikes against an antifriction bowl a carried in the upper end of a
vertical or nearly vertical lever O; this lever oscillates on the stud
centre b, and its lower end is bent in the form of an elbowe, as

page_text: shewn clearly in Figure 4. The extremity of this elbow c works in
contact with the rounded end of a corresponding elbow bend d on the
rear end of a horizontal lever P centred on a stud Q projecting from the
under side of the bed plate or table. The opposite end of this lever has
a long slot e made therein, through which passes a screwed pin f
provided with a tightening nut g; this pin enters also a slot made
longitudinally in a second horizontal lever R, which is parallel to the
lever P, but situate above it, and works at its front end on a fixed stud S
projecting from the under side of the bed plate. By slackening the nut g
the screwed pin which connects the two horizontal levers is free to be
adjusted along the slots e and respectively, and again fixed by
tightening the nut in order to vary the range of motion transmitted
by the lever P to the lever R, the range of motion of the former being
practically always the same, as it is dependent solely upon the throw of
the wiper N, the length of the vertical lever O, and the position of the
fulcrum of that lever.. T is a helical spring, which serves to bring
back the lever P after it has been acted upon by the end of the vertical
lever O. The lever R bears constantly against the front end of the
horizontal feed bar U, and serves to impart thereto the forward motion
requisite for propelling the cloth or other material being stitched, a
roughened or serrated plate (Figure 3) attached to the feed bar being
caused to act directly upon the cloth through an aperture in the cloth
plate, as is well understood in this class of machinery. The feed bar
works between two guide lugs at or near its front end, and is
maintained therein (but allowed perfect freedom of horizontal motion)
by a pin passing transversely through a slotted opening in the feed
bar, and through the guiding lugs. V is a helical spring, which serves
to return the feed bar to its original position again after each impulse
imparted to it by the horizontal lever R, thus completing the to-and-fro
horizontal motion of the said feed bar. The vertical or up-and-down
motion is imparted to the feed bar by a lever W working on a fixed
centre X, and carrying an antifriction bowl Y, which rests upon the
segmental rocking cam M herein-before referred to; this lever W is
provided with a sliding piece Z capable of adjustment along it towards
or from its centre of oscillation, and of being fixed in any desired
position by the pinching screw i. An antifriction bowl k is carried by
the adjustable sliding piece Z, and bears against the under side of the
feed bar U, the latter being pressed downwards so as always to remain in
contact with the antifriction bowl k by a blade spring (Figure 3) fitted

page_text: into a recess cut in the under side of the table or bed plate. By properly
timing the motions of the wiper N and segmental cam M, it follows that
the horizontal and vertical motions of the feed bar U will occur in their
proper order, and by adjusting the pin falong the slotted levers P and R,
the forward motion of the feed bar will be increased or diminished, and
the length of the stitches varied accordingly, whilst at the same time
by adjusting the slide Z along the lever W the vertical throw of the
feed bar will also be varied so as to accomodate it to the nature of
the fabrics operated upon.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is,-
First. The combination of the coupled levers P and R worked by a
cam or its equivalent with the lever W and segmental rocking cam M
for imparting the horizontal and vertical motions to the feed bar of a
sewing machine, substantially as herein-before described.
Second. The application and use of the pin fmade adjustable along
slots in the levers P and R, for the purpose of varying the length of
stitch in a sewing machine, substantially as herein-before described.
Third. The combination of the lever W, adjustable slide Z, and
segmental cam M, for the purpose of varying the extent of the vertical
motion of the feed bar of a sewing machine, substantially as herein-
before described.
In witness whereof, I, the said John Henry Johnson, have to this
my Specification set my hand and seal, the Nineteenth day of
January One thousand eight hundred and seventy.
J. HENRY JOHNSON. (L.S.)