IMPROVEMENTS IN SEWING MACHINES FOR OVERSEAMING BUTTON HOLES AND SUCH LIKE
Year: 1885

page_text: CUMILLIC
DIECIFICATION.
I ALEXANDER ANDERSON Manager of the Singer Manufacturing Company's
Works at Kilbowie Dumbartonshire and at Glasgow Lanarkshire do hereby
declare the nature of my invention for "IMPROVEMENTS IN SEWING MACHINES
FOR OVERSEAMING BUTTON HOLES AND SUCH LIKE" and in what manner the
same is to be performed to be particularly described and ascertained in and by
the following statement :-
Heretofore in sewing machines for overseaming the edge of a fabric the work has
been in some cases performed by a needle which not only had the ordinary up and
down motions imparted to it but also a to and fro sideway movement so that it
might pass alternately through the fabric and at the next stitch outside the edge of
the fabric and with such machines a shuttle has been used to interlock its thread
with the needle thread-but in machines for overseaming button holes eyelet holes
and such like in which the work is held in a clamp noved automatically by &
rotating cam plate below the surface of the bed or table of the machine it has not
been practicable to employ a shuttle to interlock its thread with the needle thread
as owing to the thickness of the cam plate the shuttle would have had to be too far
below the table for it to enter with certainty the loop thrown out from the needle
because the shuttle would have been too far from its work, that is there would have
been too long a length of the slender needle stem intervening and uncontrolled
between the point at which the needle passed through the work and the point
where the nose of the shuttle would have to enter the loop thrown out from it.
Consequently whenever the work has been held in a clamp moved automatically by
a cam plate lying in a recess in or below the table to allow of a button hole eyelet
hole or such like being overseamed the interlooping of a second thread with the
needle thread has had to be performed by means of mechanism known as loopers
and spreaders by which the second thread has not only been interlooped with the
needle thread but also with its own loops so forming a "purl" or complicated
interlooping of the loops.
This mechanism though well adapted for sewing with silk thread is not equally
well adapted for sewing with rough cotton or linen thread owing to the excessive
friction on the thread in forming the interlooped stitch.

page_text: By my invention I am enabled not only to use an extremely short needle but
also to use a shuttle to interloop its thread with the needle thread and consequently
owing to the comparatively small amount of friction put on the thread by the
shuttle I am able to render such machines capable of being worked not only with
silk but also with rough cotton or linen thread.
To effect this I employ a shuttle formed with a long projecting beak such as is
described in the Specifications of Patents No 2813 in the year 1878, N° 3079 in the
year 1879 and No 3141 in the year 1880 and which is made to oscillate or rotate
in a circular course in a vertical plane parallel or practically so with the plane in
which the needle has the sideway to and fro motion given to it.
By making the shuttle to oscillate or rotate in this plane the upper part of the
shuttle race or the shuttle carrier can be made to lie within a large circular opening
formed through the centre of the cam plate above mentioned so that the pointed
end of the shuttle beak can be made to pass immediately below the eye in the
throat plate through which the needle descends and consequently a very short
needle can be used. The advantage derived from employing a shuttle with a long
projecting beak is that the needle can have a continuous up and down motion given
to it from a revolving crank.
When the shuttle has a rotary oscillating movement given to it I give motion to
the shuttle driver as herein after described from a cam groove formed on the under-
side of a disc carried at the lower end of a vertical axis at the back end of the
machine. The whole machine I prefer to construct in the manner herein after
described and illustrated in the Drawings annexed.
Figure 1 is a vertical soction and Figure 2 an underside view of the machine.
Figure 3 is a transverse vertical section through the machine table and Figure 4 is
a plan of the same showing the cloth clamp and operating mechanism.
In the machine shewn in the above figures the shuttle is made to oscillate to and
fro in a fixed circular shuttle race but it might if preferred be simply carried in a
carrier either rotated or made to oscillate in the arc of a circle.
A is the bed plate or table of the machine. B a standard rising from its back
end and C an arm extending forwards over the table in the ordinary manner.
At its forward end the front face of the arm has a frame D jointed to it. The
hinge joint is at one side of the frame-the other side is connected by a link to a
bell crank lever E by means of which this side of the frame can be moved forwards
or backwards.
The needle bar is carried by this frame and can be moved up and down in guides
formed in it. It receives its up and down motion by a connecting rod passing to a
crank pin on a disc at the end of the driving shaft F.
The driving shaft by bevil wheels gives motion as heretofore to a vertical shaft
passing down through the standard B. On this shaft is a cam for giving motion to
the lover Eon the lower end of the shaft is also a disc G. In the upper face of
this disc is a cam groove for giving a rocking motion to a lever H by which
a rotating step by step motion is to be given to the cam plate I by which the clamp
in which the work is held is driven.
The cam plate I lies in an annular recess in the upper face of the bed plate A
concentric with the needle-it has a step by step rotating motion given to it by a
driving "dog" or piece J at one end of which is an oblong projection J* which
enters a circular groove J¹ in the underside of the cam plate I and to the other end
of which is jointed a lever K on the shorter arm of which is a pin K³ entering a
second cam groove L formed in the underside of the disc. The piece J is constantly
drawn in one direction by a spring M-it is moved from time to time in the
opposite direction by an arm of the lever H striking against the longer arm of the
lever K-this makes the pin K' and the oblong projection J* above mentioned bind
against the sides of the grooves into which they enter thereby locking the piece J
to the cam plate and consequently the cam plate is rotated a distance each time
that the lever H comes against the lever K.

page_text: When the pin K on the lever K is in one portion of the cam groove L the
lever K will be in the position shown in the drawing and a comparatively short
step by step movement will be given to the cam plate as a projection from the
lever H near its axis then acts upon the extremity of the longer arm of the lever K
and the extremity of the lever H does not come into contact with it but when the
disc as it rotates comes into such a position that the pin K³ enters that portion of
the cam groove L which is furthest from the axis of the cam plate then the lever K
before it locks itself to the cam plate will be free to turn into such a position that
the piece J when drawn backwards by the spring will be drawn backwards until
the longer arm of the lever K comes against the extremity of the arm H so that the
arm H in its to and fro movement will then give a long travel to the ring at each
movement. The cam plate is prevented from turning backwards in the wrong
direction by a friction block pressing against the edge of the disc as is usual.
In the upper face of the cam plate is a cam groove N. A pin 0¹ projecting
downwards from the plate O, which carries the clamp enters this cam groove the
pin also passes down through a slot P¹ in the cover plate P by which the annular
recess in the face of the table is covered over. The two ends of this groove are
straight and the central portion concentric with the needle.
When the cam plate I has a step by step motion given to it as above described
the pin which projects down from the clamp into the cam groove N formed in it is
by this groove forced along the first straight portion of the slot P¹ and when it has
come to the end of this straight portion the end of a piece N' hinged to the cam
plate obstructs the entrance of the pin into the continuation of the cam groove-
the end of the piece N¹ therefore drives the pin before it into the semi-circular
portion of the groove in the cover plate and therefore gives a half turn to the
clamp. When the pin has arrived at the end of this semicircular portion of the
slot the piece N' comes opposite to a recess in the side of the annular groove in
which the cam plate turns-the piece N¹ can so move inwards towards the centre
and so get clear of the pin O¹ and the remainder of the cam groove will then act
on the pin to cause it to travel along the second straight end of the groove in the
cover plate.
:
Whilst the clamp is having a half turn given to it as above described the
overseaming of the circular eye at one end of the button hole is being performed
and the cam plate is during this time moved with long steps in the manner above
described so that the successive stitches may not be packed too close together
around this portion of the edge of the button hole, but whilst the pin is being
made to travel along in a straight path and one or other side of the button hole is
being sewn over, the cam plate moves with comparatively short steps. Q' is a pawl
carried by a lever Q which can be rocked to and fro by hand-the pawl is by a
spring Q³ made to engage with ratchet teeth formed around the circumference of
the cam plate so that by rocking the lever Q the cam plate can quickly be brought
into any desired position to bring the clamp into proper position for overseaming
the slit formed in the work.
When the machine is in operation the pawl is held away from the teeth on the
cam plate by its being brought by the spring Q2 against a stop Q³ but when a
button hole has been formed as above described the cam plate can quickly be turned
round into position to commence another hole by rocking the lever Q to and fro by
hand.
"
The plate O which carries the clamp upon which the work is held lies above the
cover plate P and has a slot in it which embraces the central cylindrical upward
projection of the throat plate this throat plate is fixed in the centre of the cover
plate P and through it is formed the eye through which the needle descends;
a flange on the upward projection of the throat plate overlies the sides of the slot
in the plate O and holds the plate down. An enlargement is formed at each end of
the slot through which the flange can pass to allow the plate to be put into or taken
out of place.

page_text: The plate O has two arms R jointed to it serrated at their ends which are
towards the needle. Above these are two other serrated plates S¹ carried by
arms S which are also jointed to the bar on the same joint pins. These upper
plates S¹ can be lifted away from the serrated ends of the arms R to allow of the
work being placed between them by a crank pin at one side of an eccentric S
being connected by a link to a bar which passes below both arms S. The eccentric
is provided with an arın T by which it can be turned.
By turning the eccentric in the opposite direction its eccentric circumference will
be made to press against another bar which lies across the top of the arms S and
50 force these arms downwards and cause them to grip and hold the fabric. The
serrated ends of the arms R with the plates S¹ above them can also be moved away
from one another after a slit for the button hole has been cut through the work so
as to open the slit to allow of its edges being overseamed. This moving apart of
the serrated ends of the arms R and of the arms S above them is effected by
pins R¹ which pass through these arms also passing through eccentric slots in a
lover U which can be turned around the pin O. V is a roller carried by a spring V¹
it presses against the edge of the clamp plate and keeps it pressed towards the
central upward projection of the throat plate and so steadies the clamp plate in its
movements.
To cut the button hole slit in the work I employ as heretofore an anvil W
it turns on a pin at W' and is acted on by a cam Y₁ on an axis Y so that it can be
made to rise up through a slot in the can ring and support the work whilst at the
same time a cutter or punch X carried by a lever arm X¹ is made to descend on to
the work to cut a slit in it. The arm X being connected by a link to an arm on
the axis Y as is usual. In this way the punch and anvil are made to act simul-
taneously in the well known manner by giving a partial turn to the axis Y by a
lever arm Y2 fast upon it.
In the drawings the clamp plate is shown to be drawn back into position for the
cutter to be so brought down on to the work to cut a slit in it. When the slit has
been cut the two pairs of clamp jaws are moved slightly away from one another as
above described to open the slit and the pin O' is litted to disengage it from the
fixed stop O the clamp plate is then slidden forwards until the pin O' can enter
the slot in the cam plate-the overseaming of the button hole can then be
commenced.
Z is a reel from which a stout thread or cord can if desired be led through a
small circular hole in the throat plate seen in Figures 1 and 2 to be laid along the
edge of the button hole and stitched to it.
All the parts of the drawing which I have above described are parts which have
before formed part of sewing machines made by "The Singer Manufacturing
Company" but have described them fully so that the construction and operation
of my improved machine may be well understood.
a is the circular shuttle race which I employ in conjunction with the parts above
described it is carried by arms a' which extend from, a block a² secured to the
underside of the bed plate. As will be seen the upper part of the race extends
upwards into the circular opening formed through the centre of the bed plate and
comes close up to the under side of the throat platc.
The shuttle driver d is constructed as described in the specifications herein before
mentioned its axis e is carried in a long bearing in the block a² and on the end
which projects beyond the bearing is a pinion which gears with a toothed rack
on a rod b. The opposite end of this rod is jointed to one arm of a lever c the
other arm of which carries a bowl that enters a cam groove in the underside of the
disc G. In this way the requisite rotary oscillating motion is communicated to the
shuttle driver other means might however be adopted for giving to it this rotary
oscillating motion.
As before stated a continuous rotating motion might be given to the shuttle
in place of an oscillating rotary motion. One way in which a continuous rotating

page_text: motion may be given to the shuttle driver is to gear the axis of the driver by bevil
wheels to one end of an axis which at its opposite end is similarly geared by bevil
wheels with the lower end of the vertical shaft which passes up through the
standard B.
In the drawings above described the mechanism employed for giving movement
to the clamp in which the work is held is adapted for stitching button holes and
for forming them with a rounded eye or end but for other forms of button holes
or for eyelet holes the mechanism for giving motion to the clamp would have to be
modified accordingly by altering the shape of the cam or otherwise as will be well
understood.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
1. The combination with the "zig-zag" needle and automatically operated cloth
clamp of a shuttle oscillated or rotated in a circular path immediately below the
throat plate and in a vertical plane parallel or practically so with the plane in
which the needle is moved sidewise to and fro substantially as described.
2. The combination with the cloth clamp and its automatic feeding gear of a
shuttle operated from the same shaft substantially as described.
3. The combination of parts constituting the improved sewing machine for
overseaming button holes and such like substantially as hereinbefore described and
illustrated in the drawing annexed.