IMPROVEMENTS IN SEWING MACHINERY
Year: 1877

page_text: LETTERS PATENT to John Keats, of Wood Green, in the County of Middlesex,
Mechanical Engineer, for the Invention of "IMPROVEMENTS IN SEWING
MACHINERY."
Scaled the 28th August 1877, and dated the 17th March 1877.
PROVISIONAL. SPECIFICATION left by the said John Keats at the Office of
the Commissioners of Patents on the 17th March 1877.
JOHN KEATS, of Wood Green, in the County of Middlesex, Mechanical Engineer.
"IMPROVEMENTS IN SEWING MACHINERY."
The chief object of this Invention is to increase the speed of that class of
wax-thread sewing machines in which a shuttle is employed above the work for
laying a lock thread in the loop of the hook thread, and thereby producing a lock
stitch.
Hitherto in these machines a reciprocating shuttle has been employed, and two
instruments were used for opening and expanding the hook thread to facilitate the
passage of the shuttle through the loop. I now propose, in place of a reciprocating
shuttle, to use a rotating shuttle of peculiar construction, which will seize the loop
as it is opened, and expand it by the act of rotating, to lay the lock thread in the
open loop.
It is well known that when operating with waxed threads the mechanism is
liable to become clogged by an accumulation of wax on the supporting surfaces and
drivers of the shuttle. To avoid this I now provide that the waxed threads shall
not touch either the drivers or the supporting surfaces, and I employ in place of
reciprocating revolving drivers, which will be so operated as always to keep clear of
the waxed thread, the shuttle, whose perimeter is circular, will conveniently take
a formn approaching to that. of a cylinder closed at both ends; this shuttle I mount
horizontally in a pendent bracket holder provided with an upper and a lower fork
between which the shuttle will be supported. The lower fork I propose to make
moveable, holding it in place by a catch, a coiled spring, or some equivalent
contrivance, the object being to depress it to allow of the facile insertion of the
shuttle and its ready removal from the machine when its supply of thread is
exhausted.

page_text: A convenient mode of driving tho shuttle will be to use a pair of vertical pins,
which are free to slide through a rotating disc, plate, or guide carried by a vertical
spindle receiving rotary motion from the cam shaft. These vertical pins or drivers
propose to support by a cam affixed to a bracket pendant from the head of the
machine, which cam will form a race for the upper ends of the pins or drivers to
travel in. The lower ends of these drivers will project into recesses made to receive
them in the upper face of the shuttle, and they will be caused to rise alternately out
of contact with the shuttle in order to allow of the passage of the loop of the hook
thread under them.
The perimeter of the shuttle is recessed transversely to form a hook, which will
catch into the opened loop of the hooked thread, and carry that thread around with
it until it has nearly completed one rotation; the shuttle hook will then be in rear
of the loop, and the loop will thus be free to escape from the shuttle. The shuttle
will however have laid its thread in the loop, which when drawn tight will be
secured or locked in the usual manner.
An important advantage consequent on the uses of this form of shuttle will be
that the loop when caught by the shuttle hook will be retained in the recess formed
to receive it, and free from contact with the adjacent parts of the mechanism while
in connection with the shuttle, there will be therefore no tendency for the mechanism
to get clogged with wax.
It will also be understood that as the shuttle is made to rotate its speed may be
indefinitely increased.
I also propose to apply the horizontal shuttle, constructed as above described, to
shuttle machines of the ordinary class, in which a vertical needle is employed to
pierce the fabric, and form by a dwell in the course of its ascent an open loop for
the passage of the shuttle. In this case instead of mounting the shuttle in a
pendant forked bearing above the support for the work, I mount it in a similar
bearing below the table of the sewing machine, and I drive the shuttle by recipro-
cating revolving pins, or their equivalent, which are brought into contact with the
under side of the shuttle. This arrangement will have the advantage over the
rotating spools or shuttles hitherto employed of subjecting the needle thread to less
friction than heretofore, and of avoiding kinks in the shuttle thread.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Keats in the Great Seal Patent Office on the 13th September
1877.
JOHN KEATS, of Wood Green, in the County of Middlesex, Mechanical Engineer.
"IMPROVEMENTS IN SEWING MACHINERY."
The chief object of this Invention is to increase the speed of that class of waxed
thread sewing machines in which a shuttle is employed above the work for
laying a lock thread in the loop of the hook thread, and thereby producing a
lock stitch.
Hitherto in these machines a traversing reciprocating shuttle has been employed,
and two instruments were used for opening and expanding the hook thread to
facilitate the passage of the shuttle through the loop. I now propose in place of
this reciprocating shuttle to use a horizontal shuttle of peculiar construction, whose
perimeter is circular, and which is provided with a book to seize the loop as it is
opened by the divider. The loop thus seized is expanded by the rotating action of
the shuttle, which at the same time lays the locking thread in the open loop.
In Sheet I. of the accompanying Drawings Fig. 1 is a side view of a waxed thread
sewing machine in which my improved arrangement of shuttle, in combination with
an under feed, is shown. Fig. 2 is a front view of the machine, and Fig. 3 is a
sectional plan taken in the line 1, 2, of Fig. 1.

page_text: In these Figures A is a standard of cast iron for supporting the various parts of
the machine. To this standard, near its foot, a tubular bracket casting A' is bolted,
which forms a bearing for the horizontal driving shaft, and also a footstep for the
vertical cam shaft, which is further supported by bearings attached to the side of the
standard. Bolted to the upper part of the standard A is the guide box A2, in which
slide the hook bar and presser bar. On the under side of this guide box A³ is
bolted a bracket A³ for carrying the shuttle and the means for driving the same,
which parts are shown in detail on an enlarged scale in Sheet II. B is the hollow
support or pillar for the work, supported on a hollow casting or box B¹, which is
bolted to the standard A. C is the hook bar carrying a hook c at its lower end.
D is the presser bar, and d the presser foot, which is held down on the work by
springs d, . The hook c, as is well known, pierces the work and draws up the
loop of waxed thread from below the work, which thread is supplied to it by the
looper E. This looper has its bearings in the pillar B, and it receives an alternating
axial motion in the manner herein-after described. The pillar top, which forms the
table for supporting the work, is pierced as usual to allow of the descent of the
hook c into the looper, and it is also slotted to allow of the feed foot f, carried by
the feed bar F, projecting up through the table and bearing on the under side of the
work.
Above the work is situate the shuttle g, which is held in place between forked
plates G, G. This shuttle is so formed as to permit of its entering the loop brought
up by the hook so soon as that loop is opened out, and in passing through it to
leave a locking thread therein, while at the same time it prevents the contact of
the waxed thread with the plates which carry the shuttle and form the shuttle
race.
For the purpose of opening the loop drawn up by the hook c, and of releasing
.it from the hook and presenting it to the nose of the shuttle, a finger or divider h
is provided as heretofore, the same being carried by a rocking arm H.
The cams for working the several instruments c, d, e, f, g, and h, are mounted on
the vertical cam shaft K, which receives rotary motion from the driving shaft L
through frictional bevil gears, as shown in Fig. 1. The driving shaft L is free to
move endwise in its tubular bearing to permit of its being thrown into and out of
action. The frictional gears are held in contact by a treadle L' connected per-
manently to that shaft by a pin which fits an annular groove turned in the shaft,
and they are thrown out of gear by a spring interposed between the treadle L¹
and the standard A. The hook bar C is worked by the cam C¹, in the groove of
which a bowle carried by the lever C³ works. This cam is shewn as laid out at
Fig. 14, Sheet II. The lever C is mounted on a pin C³, secured between the
standard A and a strap picce A*, attached to the standard. The opposite end of the
lever C is forked, to embrace a pin which projects from the bar C. As therefore
the cam C¹ is rotated a reciprocating vertical motion is imparted to the hook bar
and hook, whereby the latter is caused to pierce the work, fetch up a loop of waxed
thread from the looper E, and present it to the shuttle.
While the rising of the hook through the work takes place, the presser foot dis
held down firmly on the work to resist the pull of the hook. For this purpose the
tension of the two springs d², d², is employed, the former of which connects directly
with the presser bar and is always in action, while the latter (d) connects with the
bar through a crank lever D', having for its fulcrum the pin C³, and carrying at its
inner end a bowle that is acted upon by a cam projection D² on the under side of
the cam C¹.
The crank lever D¹ rests in a recess in the side of the bar D, and it is held down
in contact with a shoulder of that recess by the spring d. So soon, however,
as it is desired to feed the work, the pressure of the spring is taken off the
presser foot by the cam projection D² coming into contact with and tipping the
lever D¹.
-
To enable the work to be shifted or removed the presser foot is raised out of
action by the excentric D³ as usual. The looper E which consists of a tube pierced

page_text: laterally at its upper end at e to receive the waxed thread c¹, is worked from a
cam E¹, shewn detached at Fig. 15. The groove in this cam is entered by the bowle
of a rock lever E, the outer ond of which terminates in a segment rack fitted to
gear with a pinion E keyed on the hollow stem of the looper (see the horizontal
view, Fig. 3). By the rotation of this cam an axial notion is imparted to the looper 5
alternately in opposite directions, and it is thereby caused to lay its waxed thread
into the barb of the hook c, and then return to its normal position. This waxed
thread is drawn from a spool E' carried by a bracket piece attached to the standard,
and on leaving the spool it passes under a guide pulley E³, and thence upwards
through the centre of the looper.
The under feed is worked by means of two cams F1 and F, the former of which
imparts the forward motion to the feeder, and the latter the up-and-down motion.
These cams are shown at Figures 16 and 17, the latter representing the cam F" as
laid out. The return motion of the feeder is effected as usual by the drag of
a spring.
The feed bar F is jointed to and carried by a rock lever F³, pivotted to the
standard A. A bowle of this lever enters a groove in the cam F, and by the
rotation of this cam the feeding foot fis pressed up to the under side of the work
and withdrawn therefrom, as is well understood.
1
1
The forward motion of the feeding foot is transmitted from the cam F¹, through 2
the crank lever F, which rocks on a pin carried by the hollow casting B¹, and is
connected by a link (see Fig. 3) to a pin on the feed bar. This rock lever after
cach advance movement of the feed bar is drawn back by a spring F5, and held in
contact with an adjustable stop pin F, which serves to determine the length of the
feed motion, and consequently the length of the stitches.
As the chief peculiarity of the Invention lies, as before stated, in the construction
and operation of the shuttle, I have shewn the shuttle in detail on an enlarged scale
in Sheet II. of the Drawings, and also the parts in connection therewith for sup-
porting the shuttle in the machine, and for giving it a reciprocating axial motion.
Before, however, I describe these in detail I will explain the means for actuating
the finger or divider k, which opens the loop drawn up by the hook, and releases it
from the hook, and presents it to the nose of the shuttle. His a cam, in the groove
of which the bowle of a compound rock lever H works, the same being pivotted to
lateral projections on the standard A. This cam is shewn as laid out at Fig. 18.
The pendent arm of this lever H carries the finger or loop divider h, which is set at
right angles thereto. The rotation therefore of the cam H¹ gives an approximate
horizontal to-and-fro motion to the divider, thereby causing it to advance to and
take up the loop, present it to the nose of the shuttle, and then retire.
Referring now to Sheet II. Fig. 1 is a plan view of the shuttle; Fig. 2 is a front
view of the same; and Fig. 3 is a cross section taken on the line 1, 2, of Fig. 1.
The shuttle may be described as a cylindrical case of steel with a vertical recess g¹
made in its perimeter, and having as a continuation of one side of this recess à cain-
shaped projection, which forms the nose of the shuttle. Access is obtained to
the interior of the shuttle by means of a hinged cover ³, shown detached at
Fig. 3, which closes the bottom thereof, and which is held fast when closed by
means of a snap spring 7. This spring is recessed into the perimeter of the shuttle,
and is so shaped as to conform to the profile of the shuttle and present no obstruc-
tion to the smooth passage of the loop around the shuttle. The space in the shuttle
for the cop of waxed thread is excentric by reason of the vertical recess g³ formed
in the shuttle. The thread passes out through a central hole in the hinged cover g³
to an eye g³ affixed to the hinged cover, and thence to the work. By this arrange-
ment a drag is at certain periods of the work put upon the cop thread, and
unnecessary slack is thereby prevented from being formed.
The nose of the shuttle stands up above its flat top externally of the cylindrical
perimeter thereof, and clear of the upper supporting plate hereafter mentioned, as
shewn at Fig. 4, in order to facilitate its entering the opened loop of the hook
thread, and its under side is chamfered off, as shewn at Fig. 2. The shuttle is

page_text: supported between two forked plates G, G¹, which are shewn detached and in plan
view at Figures 5 and 6. The upper plato G is made fast to the bracket casting A³,
as shown bost in the detached views Figures 7 and 8, and the lower plate G³ is
attached to a sliding bar C2, shown in side olevation and plan view at Figures 9,
which bar fits into a vertical slot in the casing A³, and is locked in place by a
spring bolt G, shewn best in the sectional plan at Fig. 10. This mode of sup-
porting the lower plate G¹ is to facilitate the removal of the shuttle from its circular
race and its replacement therein, it being merely necessary to pull back the spring
bolt G³ to release the shuttle. Theso plates are rebated on the inner face of their
forks to receive the shuttle and form guides for it during its axial motion.
For driving the shuttle a pair of vertical rods i, i*, (sce the sectional elevation,
Fig. 11) is used, which rods enter holes or circular recesses in the top of the
shuttle, and are altornately lifted out of contact thorewith.
Those rods (see
Fig. 10) slide in guides made for them in the vertical spindle I, which turns in a
bearing provided for it in the casting A". Surrounding this spindle is an annular
cam I, shown detached at Figures 12. This cam is composed of two parts con-
nected together by strap picces, which enter vertical slots made for them in tho
hollow casting A³. These straps, besides connecting the parts of the cam together,
servo to secure the cam in its proper position in the casting. Into the groove of
this cam, which is laid out at Fig. 12a, bowles, carried by the rods i, i*, enter, and
as axial motion is given to the spindle I the rods i, i*, will in moving round with
the spindle be alternately lifted clear of and brought into contact with the shuttle.
Thus as these rods i, i*, revolve or partially revolve around a common centre they
will impart an axial motion to the shuttle. The spindle I is driven by means of a
pinion which it carries (see the detached view, Fig. 13, and also Fig. 1, Sheet I.),
gearing into a segment rack attached to one end of a horizontal rock lever I*
pivotted on the casting A². This lever is reciprocated by a bowle which it carries,
entering the groove of a cam I³, shown detached at Fig. 19.
The rise of the rods i, i, is so arranged that the loop of the hook thread will be
free to pass under them as it is drawn over the shuttle to receive the locking thread,
and their depression is so timed that one rod will always be in contact with the
shuttle.
Having now described the means for actuating the several parts I will proceed
to explain by the aid of diagrams the manner in which the sewing is effected
in the machine shown in Sheet I.
Figures 1, Sheet III., shew in plan and elevation, on a slightly enlarged scale,
the sewing instruments in the position which they assume when the hook c has
just transferred its loop to the divider h, which, opening it in the act of receiving the
loop from the hook, presents it to the nose of the shuttle g.
Rotary motion being now given to the shuttle in the direction of the arrow the
loop is drawn into the recess g¹ of the shuttle, as indicated in Figures 2, and at this
time the rod i* will be lifted to permit of the loop passing under it as the shuttle
continues to rotate in order to lay its locking thread into the loop of the hook
thread. The continued axial motion of the shuttle brings it to the position shewn
in Figures 3, at which time the feed of the work will take place. The loop also
will at this time get clear of the divider h.
Before the shuttle has arrived at the position shown at Figures 4 the rod i will
require to be lifted, the rod i* having meanwhile been dropped into contact with
the shuttle. On the lifting of the rod i the loop will pass under it, and when the
shuttle has attained the position of Figures 4 its locking thread will be laid into
the loop of the hook thread. While this is taking place the hook moves down
through the work to fetch up another loop, and in rising it will put such a tension
on its thread as to draw the last loop off the shuttle. As the hook continues to
rise it will draw the last loop tight, as indicated at Figures 5, and the axial motion
of the shuttle being now reversed, as indicated by the arrow, the nose of the shuttle
will be brought back to the position of Figures 1, ready to enter the new loop which
is held suspended by the hook.

page_text: '
A repetition of the motions above mentioned will produce a seam, each stitch
being firmly locked by the shuttle thread.
During these operations it will be understood that the loop of the hook thread
never comes in contact with the race or bearing surfaces of the plates G, G¹, and
consequently those parts are not liable to become clogged by an accumulation of
wax derived from the saturated hook thread. In like manner the drivers i, i*,
being kept clear of the loop of waxed thread as it is drawn over the shuttle there
will be no tendency for wax to accumulate on them and interfere with the efficient
working of the machine.
Having now set forth the nature of my Invention of "Improvements in Sewing
Machinery," and explained the manner of carrying the same into effect, I wish it to
be understood that under the above in part recited Letters Patent I claim,-
First. A circular shuttle, constructed and operating as above described.
Secondly. The combination of a circular horizontal shuttle race set above the
table or work supporter, with a shuttle so constructed and operated that it will pass
through the loop of the hook or needle thread without that thread being brought
into contact with the shuttle supports or driver.
Thirdly. The arrangement of mechanism above described, whereby the circular
shuttle placed above the work is enabled to take the opened loop of the hook thread
from the divider and lay a locking thread therein.
In witness whereof, I, the said John Keats, have hereunto set my hand and
seal, the Twenty-ninth day of August, in the year of our Lord Ono
thousand eight hundred and seventy-seven.
JOHN KEATS. (L.S.)