IMPROVEMENTS IN SEWING MACHINES
Year: 1882

page_text: LETTERS PATENT to Frank Wirth of the firm of Wirth and Company
Patent Solicitors, at Frankfort on the Main, in the Empire of Germany for an
Invention of "IMPROVEMENTS IN SEWING MACHINES." A communication
from the firm of Junker & Rub, Manufacturers of sewing machines at
Karlsruhe in the Empire of Germany.
PROVISIONAL SPECIFICATION left by the said Frank Wirth at the Office of
the Commissioners of Patents on the 4th July 1882.
FRANK WIRTH of the firm of Wirth and Company Patent Solicitors at
Frankfort on the Main, in the Empire of Germany,
"IMPROVEMENTS IN SEWING
MACHINES [A communication from the firm of Junker & Ruh, Manufacturers
of sewing machines at Karlsruhe in the Empire of Germany.]
"
This invention relates to sewing-machines and comprises various improvements
hereinafter set forth: According to the said Invention I provide under the bed-
plate of the sewing-machine, a block having three spokes or arms which are
connected with a ring or circular piece; this ring carries the guides for the feed-
bar as well as a check or extension and a hollow boss or lug, in which is fitted a
pin or stud. Close to the said block an excentric is fixed upon the main shaft
and a driver is connected therewith. A groove is turned in the ring which has also
an opening or cavity at the top and within which a rotating shuttle or reel-holder,
moves and is adapted to be rotated by the said driver. The aforesaid excentric
communicates motion to a bent excentric rod, which, at one end, is guided by means
of sliding pieces upon the aforesaid pin or stud, whilst the other end transmits
motion, by means of a bolt or pin, to a link-piece connected to the feed-bar. The
motion of the feeder which is secured to the feed-bar is increased or diminished
by means of a stitch-regulating lever. The rotating shuttle or reel-holder, consists of
a half disc, with a recess to receive the reel. On this disc there is a semi-spherical
part which tapers towards the sides, and forms at one end a hook or point.. On
each side of this semi-spherical part is fixed a plate, one of which plates is. con-
nected with it by means of a hinge, and both are arranged to enclose the reel.

page_text: The stitch is produced as follows, that is to say. After the needle-thread, by
the motion of the needle-bar upwards, has formed a loop, the point of the reel-
holder passes through it, as it rotates forward, the loop is made to lie on both
sides of the semi-spherical part, and is spread out, by the same, until the shuttle can
pass through it. At this moment the upper thread begins to be tightened whereby
the reel-holder is lifted a little in order that the thread may slip in between the
driving arm and the reel-holder. After a further drawing, the loop reaches a
second driving arm and there also slips through in the same manner. After the
loop has passed the reel-holder the thread of the latter is inside the loop and the
complete tightening is then effected by the reel-holder pressing the lower thread
away from the upright position towards a stitch plate outwards, whereby it finds
a resistance on the two plates enclosing the reel.
In order to set the needle I provide a round needle-bar which has a shoulder
of the same length as the tightening ring and is slit according to the length
of an enclosed piece which has on one side a shoulder so that it will not fall
out, and on the other side an inclined surface extending throughout its length,
by means of which it is held hard and fast at three points by means of a screw
which presses against the said piece.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Frank Wirth in the Great Seal Patent Office on the 2nd
January 1883.
FRANK WIRTH, of the firm of Wirth and Company, Patent Solicitors, at
Frankfort-on-the-Main in the Empire of Germany "IMPROVEMENTS IN SEWING
MACHINES A Communication from the firm of Junker and Ruh, Manufacturers
of Sewing-machines; at Karlsruhe in the Empire of Germany.
"
This Invention relates to sewing machines and comprises various improvements
hereinafter set forth.
In the accompanying drawings, Figure 1 is a sectional elevation of parts of a
sewing machine embodying the said Invention, the shuttle and driver being
removed
Figure 2 is a section on the line x x Figure 1.
Figure 3 is a front view of the circular ring or shuttle carrier, with the shuttle
or reel-holder and the shuttle-driver therein.
Figures 4 and 5 show the manner in which the shuttle passes through the loop
formed in the upper thread.
Figure 6 is a longitudinal section of the work-plate and carrying bracket and
with the feed-bar in elevation and the feeder in transverse section.
Figure 7 is a longitudinal section of the work-plate with the excentric rod and
the driver in connection with the excentric.
Figure 8 is a transverse section of the reel-holder or shuttle with the driver.
Figure 9 is a horizontal section of the reel-holder or shuttle with the reel, and
Figure 10 shows the manner of setting the needle.
Beneath the workplate A of the sewing machine is fixed the bracket B having
the three arms b, b¹, b³, to which is attached the ring or circular piece B'. The said
ring has attached to it the guides b³, b, for the feed-bar C, the cheek or projection 65
and the hollow boss or lug 6. Close to the bracket B an excentric E is fixed
upon the main shaft D, and the shuttle-driver F is also connected to the said shaft.
Upon the inner side of the ring B' is formed a groove which has an opening or
cavity y at the top. Within the said groove the rotating shuttle or reel-holder
moves, being rotated by the shuttle-driver F. The excentric E communicates its
motion to the bent excentric rod G, which at one end is guided by its extremities g
and g¹ sliding on a bolt in the eye 66, whilst the other end g³ transmits motion by
means of a bolt or pin to the link-piece which is connected to the feed-bar Č.
The motion of the feeder J which is secured to the feed-bar O is increased or
diminished by adjusting the stitch-regulating lever K in the slot of the projec-
tion b. The rotating shuttle or reel-holder L is in the form of a half disc having
a recess to receive the reel and a semi-spherical part 7 which tapers towards the
edge of the disc and forms at one end a hook or point . On one side of the said
semi-spherical part is fixed the plate l, and upon the opposite side is the plate 1³
which is connected with the real-holder by means of a hinge, the said two plates
are arranged to enclose the reel. In order to introduce a reel into the shuttle or
holder, the plate is thrown back by means of a pressure in the direction of its
length, whereby its free end is released from the position shown in Figure 9.
The stitch is formed as follows, that is to say, through the motion of the needle-
bar upwards a loop is formed by the upper thread beneath the work-plate, the
point of the reel-holder as it rotates passes through the said loop as shown in
Figure 3; as the shuttle continues to rotate, the loop is caused to lie on both sides
of the semi-spherical part and is spread out by the same, as shown in Figure 5,

page_text: until the shuttle can pass through it. At this moment the upper thread begins to
tighten, whereby the reel holder or shuttle is slightly lifted in order that the thread
may slip between the driving arm fand the said reel-holder, as shown in Figure 4,
through a further rotation of the shuttle the loop reaches the driving arm f¹ and
there also slips between the said arm f¹ and the shuttle in consequence of the said 5
shuttle having passed its centre of gravity and thereby resting but lightly upon
the driving arm f¹; after the loop has passed the reel holder or shuttle, the thread
of the latter is inside the loop formed by the upper thread and the complete
tightening is then effected by the reel-holder pressing the lower thread away from
the upright position, as shown in Figure 8, outwards towards the stitch plate M, & 1
resistance is thus offered by the plates and which enclose the reel. The
looping of both threads takes place in the same manner as in other lock-stitch
sewing machines; also the parts of the mechanism not described. may be of any well
known construction.
=
In order to set the needle the round needle-bar A¹ is provided with a shoulder 1
of the same length as the ring B³, and with a slot or groove corresponding with
the length of a wedge-shaped piece C¹ which is adapted to fit within it. The said
piece has on one side a shoulder so that it will not fall out of the ring, and on
the other side an inclined surface extending throughout its length as shown in
Figure 10. When a needle is inserted between the collar B and the piece O¹ and
the screw D' is tightened, the said needle is held securely between the ring B*
and the inclined side of the piece O.
Having thus fully described the said Invention and the manner of performing
the same I wish it understood that I claim :—
First: The rotary reel-holder or shuttle L, held in the bracket B with its ring
or carrier B¹ and the parts connected therewith, and the semi-spherical part 1 for
guiding the thread, provided with the movable plate 1³ and the immovable plate l³,
substantially as shown and described.
"
Second: The feeder J, in combination with the stitch regulator, which consists
of the excentric E, the excentric rod G, the link H formed with a slot, the lever K
and the feed-bar e, all substantially as shown and described.
Third:-The means for setting the needle, consisting of a wedge-shaped piece
which is pressed against the needle by the set-screw in the ring B³, substantially
as shown and described.
In witness whereof I the said Frank Wirth have hereunto set my hand and
seal this Twenty first day of December in the year of our Lord One
thousand eight hundred and eighty two.
TDATE WIDT