Improvements in Sewing Machines.
Year: 1892

page_text: Date of Application, 9th July, 1892-Accepted, 5th Nov., 1892
COMPLETE SPECIFICATION.
Improvements in Sewing Machines.
I, KARL NECKER, of Adalbertstrasse, 69, Berlin, Germany, Merchant, do
hereby declare the nature of this invention and in what manner the same is to
be performed to be particularly described and ascertained in and by the following
statement:
This invention relates to that type of sewing machine known as an overedge or
seam-stitch sewing machine, wherein three separate threads are employed, and
which is commonly used in the making of gloves, satchels, bags, and the like;
and refers more particularly to a means whereby the third or seaming-thread is led
over the edges of the pieces of material to be sewn and connected with the threads
forming the lock stitch, and to a means of adjusting the relative positions of the
needle and shuttle.
In the drawings hereto annexed :-
Figure 1 represents a general view of a sewing machine according to my
invention.
Figures 2 and 3 illustrate devices for adjusting the relative positions of needle
and shuttle.
Figure 4 represents the seaming-thread carrier, in three different planes of
projection.
Figures 5 and 6 illustrate the mechanism for actuating the seaming-thread
carrier.
c represents the casing of an ordinary rotary shuttle; e is the needle of the
machine, and is carried by the shaft a¹ and horizontal arm d¹; the well known
movements of these two elements are effected by the mechanism usually employed
in sewing machinery for this purpose, to which therefore no reference may here
be made beyond the statement that such mechanism is contained in the casing A
and is driven by the shaft band wheel a.
By the mechanism above described an ordinary lockstitch is produced, and I
will now proceed to describe the manner in which, by my invention, a seaming
stitch is connected therewith.
designates the seaming-thread carrier, mounted upon a lever f¹ which is pivotted
at n. To the carrier fis imparted a double motion, namely it is given a vertical.
motion and a horizontal motion, whereby the seaming-thread is led over the edges
(from side to side) of the pieces of material being sewn together. For this purpose
the lever f', to which the carrier is connected, is mounted in ball and socket
bearings. On the end of the lever f' within the case A are mounted an anti-
friction roller b² and a pin 13. The roller 2 is caused to bear upon the periphery
of the cam by the spring f2, whereby a vertical rocking motion is imparted to the
lever as the cam revolves, whilst the pin 68 is caused to bear upon the face of
the cam by the spring f³, the inclined surface of such face imparting to the
lever a horizontal rocking motion as the cam revolves. It will be seen that by
imparting these motions to the lever f' in the required rotation, the carrier may be
caused to traverse the edge of the materials being sewn, from side to side, and to
dip on each side thereof, whereby the seaming thread is led under the needle at one
side of the materials, then across the edges thereof, and then under the needle as it
emerges from the other side of the materials. The seaming-thread I passes through
apertures provided in the carrier f, as will be seen upon reference to Figure 4.
i and designate the pieces of material to be sewn, which are pressed together
and fed forward by the rotary feeders g and h.

page_text: The series of movements whereby a combined lock-stitch and seaming-stitch is
produced may be thus described :-(1) The carrier descends upon the left hand
side of the pieces of material i k; (2) The needle e advances over the thread laud
enters the material; (3) The carrier rises, crosses the material-carrying the
thread with it-and descends upon the right hand side of the material; (4) The
needle emerges from the right hand side of the material and again crosses the
thread ; (5) The shuttle d. engages with the needle thread p and forms a lock
stitch, and (6) The needle e is withdrawn and the operation repeated. The relative
position of the needle e with the thread carrier f will be seen upon reference to
Figure 4.
l
Two thread reels are carried by pins u provided with spring tension devices,
upon the case A. From the reel the seaming-thread is led through the guide o
to the carrier f. From the other reel x (which is hidden in the drawing) the
needle-thread p is led through the guide q to the tension roller r, thence through
the guides (and loop of tension lever t) to the bell-crank lever w, and thence
through an aperture in the needle shaft a to the eye of the needle e. A pin e¹
upon a rocking lever e² (actuated by the mechanism of the machine) engages with
the levert at the moment when the needle-thread p must form a loop for the entry
of the shuttled and, by raising it, momentarily prevents the slack from being taken
up. This momentary slackening of the needle-thread is also provided for in the
following manner :-Upon the upper arm of the bell crank lever wis provided
the pin which, as the arm d' advances and recedes, is caused to travel along the
under surface of the guide g', being held up thereto by the spring . It will be
evident that when the pin enters the indent o² in the guide g₁ the lever w will
be canted, and the thread p thus momentarily slackened, this of course happening
when the shuttle loop is being formed. The shuttle d is provided with the usual
thread spool.
The means by which, according to my invention, the relative position of the
shuttled with the needle e may be adjusted, so that needles of varying thicknesses
may be used, will now be described with reference to Figures 2 and 3. In Figure 2
the shuttle case is carried by a pivotted arm arranged as a lever of the third order.
An adjustment screw is provided on the free end of the arm, and the set screws m
serve to fix the arm in the position to which it has been adjusted. In Figure 3 the
shuttle casing is shewn carried by a sliding block, which is similarly provided with
an adjustment screw i¹ and set screws m. A modification may consist in carrying
the shuttle case upon a pivotted arm arranged as a lever of the first order, the free
end of such arm being provided with a pivotted set screw which takes into a
graduated series of holes in the side of the casing A.
The feeders g, h, are rotated by the mechanism usually employed for this purpose,
and the feeder g is provided with the usual pedal displacing device to allow for
insertion of the material between the feeders."
o designates the button for actuating the usual device for regulating the number
of stitches in any given seam.
Instead of a rotary shuttle being used as above specified, an oscillating shuttle
may be employed as an alternative.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. "The employment in sewing machine of the type above described, of a
thread carrier such as f, operating so that a third or seaming-thread is led over the
edges of the material being sewn and connected with a lock-stitch; substantially as
described with reference to the annexed drawings.
2. The devices whereby the relative position of a rotary shuttle with the needle
used in connection therewith may be adjusted, so as to admit of the use of needles

page_text: of varying thicknesses; substantially as described, and also as set forth with
reference to Figures 2 and 3 of the drawings hereto annexed.
Dated this 8th day of July 1892.
KARL NECKER,
By Cheesbrough & Royston, Fels. Chart. Inst. P.A.,
15, Water Street, Liverpool, Applicant's Agents.