IMPROVEMENTS IN SEWING MACHINES
Year: 1883

page_text: LETTERS PATENT to William Walker of Dunstable in the County of Bedford,
Foreman to Matthew Walker of Dunstable aforesaid Straw Manufacturer
for an Invention of IMPROVEMENTS IN SEWING MACHINES
PROVISIONAL SPECIFICATION left by the said William Walker at the
Office of the Commissioners of Patents on the 10th January 1883.
WILLIAM WALKER of Dunstable in the County of Bedford, Foreman to Matthew
Walker of Dunstable aforesaid, Straw Manufacturer "IMPROVEMENTS IN SEWING
MACHINES
"
The Invention relates to a single thread chain stitch machine, producing long
and short stitches, applicable to the manufacture of straw, braid, chip, and other
hats and bonnets, and to other purposes.
The improvements in the machine consist particularly in the mechanical
arrangements for producing the feed motion, the threading of the needle, and
unthreading of the same, and retaining and releasing the loop.
In the first arrangement I employ mainly for the feed movement a block called
the feed block, which is grooved on the inner face, and said groove fits upon a bar
placed horizontally on the front face of the machine-The outer face is grooved
vertically to receive the feed and feed lever. Horizontal motion is imparted to the
feed by the revolving of a cam. This cam is fixed upon the end of the main shaft
and it is so constructed that it pushes forward the feed about 16 of an inch, and
retains it in this position until the opposite end of cam comes round, it is then
pushed forward again about 1/8 of an inch.-In conjunction with this movement,
an up, and down movement is imparted to the feed by its being connected to the
lever. This lever is connected to an eccentric fixed upon the outer face of the cam.
-The eccentric is so fixed upon the cam that when the cam commences to revolve,
the feed is raised, and it continues raised until the long end of the cam has done
its work. The feed then falls and the block is drawn back again ready for the
next revolution; thus two stitches, one long and the other short, are produced by
one revolution

page_text: The second arrangement is mainly a rotary feed.-This is firmly fixed upon a
crank connected to an eccentric or crank fixed on the end of the main shaft.-
Teeth being cut, the large end when revolving, carries forward the work for the
long stitch, and the small end for the short stitch.-The threader works in
conjunction with the needle.-This needle has two hooks, by having the eye cut
open on one side, and has a hollow on its inner and outer sides.-It moves up and
down twice to one revolution, receiving its motion from cam. The threader is
pivotted under the workplate; the other end is pivotted to a sliding bar connected
to the cam. At each alternate fall of the needle, the threader pushed forward by
the cam strains the thread round the needle; when the needle commences to rise,
the hook catches the thread; the threader is then drawn back, and remains until
the next alternate down stroke of the needle, when the movement is repeated.
The unthreader and retainer can receive oscillating motion from a pin fixed in
the cam eccentric.-The pin is made to traverse a cam path cut in the inner face
of the unthreader. The movement is timed to meet the needle when it brings
down the loop after the short stitch. It is constructed to pass into the hollow cut
in the needle, and push the cotton out of the eye and with the assistance of the
book lever (worked by the unthreader) retain the loop until the needle has gone
up empty and returned again to receive the cotton from the threader-As soon as
the needle takes the cotton and passes up through the loop, the loop is released, the
feed having in the meantime carried the work forward, the stitch being thus
formed. The action of the mechanism is as follows:-As soon as the machine is
started, the needle passes down through the work The threader strains the cotton
round the needle-When the needle commences the return movement, the cotton
enters the hooked eye.-As soon as the needle clears the work, the short feed takes.
place, the needle again descends through the work, holding the cotton, so that as
soon as the return movement begins, the cotton takes the form of a loop, the
unthreader is now propelled backward its point passes alongside the hollow in the
needle, and pushes the cotton out of the eye, the lever hook attached to the
unthreader makes a similar movement in the opposite direction, the loop is in this
way held, the needle ascends, the feed movement for the long stitch takes place, the
needle descends again, takes the cotton from the threader, and passes up through
the loop, the loop is then released by the unthreader and lever, thus the two
stitches are formed by one revolution.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent and of
an Order of the Lord Chancellor filed by the said William Walker in the
Great Seal Patent Office on the 24th July 1883.
WILLIAM WALKER of Dunstable in the County of Bedford, Foreman to Matthew
Walker of the same place Straw Manufacturer, "IMPROVEMENTS IN SEWING
MACHINES
BJ
The Invention relates to a single thread chain stitch machine producing long
and short stitches, applicable to the manufacture of straw braid chip and other bats
and bonnets and to other purposes.
The improvements in the machine consist particularly in the mechanical
arrangements for producing the feed motion, the threading of the needle and
unthreading of the same, and retaining and releasing the loop.
In order that my Invention may be clearly understood, I will now proceed by
reference to the accompanying Drawings, to describe and ascertain in what manner
the same is to be performed or carried out in practice.
Fig. 1, side elevation of machine constructed according to my Invention
Fig. 2. end elevation.-Fig. 3, plan of cam for operating the needle Fig. 4.
elevation and plan of cam for operating unthreader by means of lever Fig. 4, and
pinion Fig. 46. Fig. 4c shows the frame in which pinion (Fig 4b) works
Fig. 5, cam for producing feed.
Fig. 6, rack for actuating threader, which is actuated by lever shown in Fig. 7
Fig. 8, elevation of unthreader.
Figs. 9. and 10, Front and end views of thread retainer and cam for operating
same.
Figs. 11, 12, and 13 show the needle
Figs. 14, 15, 16, 17, and 18, show the arrangement of operating the stitch.
In these Figures, the same letters indicate corresponding parts. A is frame of
machine.-B, throader, with support K and pinion at bottom.-C is feeder.--D is
oscillating looper or unthreader E is double hook in needle-F is thread retainer
in connection with unthreader. G and H, cam or eccentric or feed motion-
I, double cam on driving shaft to give motion to needle; by connection P and O.-
K' is slide bar worked by cam L, which slides through support K, and works
threader B-M is a disc with cam groove cut in face, to work rack lever N, to work
looper or unthreader D-R is cam or eccentric to move thread retainer R' cam
to give a rocking motion to thread retainer-S shows recess in needle for looper or
unthreader to pass
The first part of my Invention consists in the production of a feed action that
will raise the teeth of feed mechanism above plate line, and maintain same there
until two stitches have been taken, one long and one short.-A double cam G H is
fixed on end of shaft Q, Figs. 1 and 2–The part g Fig, 5 is nearest the centre and
when the feed mechanism presses against this part g, it is as forward as it can
come, and as the shaft turns in direction of arrow, the movement from c to d.
propels the feed forward-Part d to e being circular, no motion would be given to
feed, but the needle and loopers would be forming their part. The shaft revolving
brings part e to f against the feeder, which gives a further movement to feed.-
Thus two distinct feeds are imparted to feeder, whilst the feeder is raised by cam
or eccentric g-This cam is to raise the feed when at point a, its lowest point-
From a to a', it rises and continues raised from a to b, and the feed is being
propelled twice, one long, one short.-Then the feed falls, and returns whilst cam or
eccentric G and H revolve from b to a, and g to c The threader B and its action
is seen on reference to Figs. 14 to 18.

page_text: The thread is drawn up through tension to hole and slot in threader, through
needle hole in work plate.-The needle descends and just before it reaches the
lowest point, the threader by rack and pinion is turned about / round, and strains
the thread round the needle.
As the needle rises, the thread falls into recess E, holding in lowest hook (Figs.
14 and 15). The threader bar K' has simply a backward and forward movement
at suitable time, as given by cam L said bar K' with teeth on end, the nearest
threader gearing into pinion on bottom of threader.-The needle is of peculiar
shape, as shown by Figs. 11, 12, and 13, After the thread is secure in the hook
of needle, the needle rises to the highest point. To prevent the thread slacking and
coming out of hook, a fine wire fixed in F called the retainer has two movements,
one to bring the wire forward in front of needle by cam or eccentric R, Fig. 1.
As soon as this is full in front of needle a rocking motion is given to it by cam or
eccentric R', which holds back the thread, and keeps same in needle as in Fig. 16,
and as the needle descends, the wire gives to the strain as in Fig. 17 until needle is
at lowest point, when the wire is withdrawn by action of cam R and R' Fig. 1,
and as soon as needle begins to rise, the thread which in its descent has been held
in top-hook of needle by means of wire retainer slightly bows out and the
hook D Figs. 1 to 8 in its movement enters this loop at side of needle cut away,
and takes the thread quite out of needle hooks, us Figs. 17 and 18, and holds it
expanded till the feed is moved forward for the long stitch, and the needle rises to
highest point, carrying nothing with it, and again descends through the loop
formed by the unthreader, when the threader returns and strains the thread round
needle again as before described. The needle rises and draws up the thread
through loop when the unthreader releases the loop, and it is pulled up as
Figs. 15 and 16, when feed is moved forward as required.
Having now particularly described and ascertained the nature of the said
Invention, and in what manner same is to be performed, I claim the Invention of
Improvements in sewing machines," substantially as herein before set forth and
described, wherein the following are important points, or features:-
11
(1.) The double eccentric for feeder, having two distinct movements, to propel
the work, giving one long and one short stitch to one revolution of the shaft, whilst
the feeder is raised to one height by the other as shown.
(2.) The combination of threader with feed cams and connections substantially
as hereinbefore described.
(3.) The looper, unthreader and connections in combination with threader feed
producing mechanism, substantially as described.
(4.) The threader retainer with connections in combination with feed cams
threader, unthreader, needle and cams, substantially as described.
In Witness whereof I the said William Walker have hereunto set my hand and
seal this twenty third day of July in the year of our Lord one thousand eight
hundred and eighty three
Witness.
T. MORGAN
21 Cockspur Street.
London S.W.
WILLIAM WALKER (L.B.)