Year: 1887

page_text: Date of Application, 11th May, 1887.
Specification Accepted. 14th June, 1887.
1
I, RICHARD OTTO of Plauen, in the Empire of Germany, Manufacturer, do hereby
declare the nature of my 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 a new or improved construction of sewing machine, by
means of which it is possible to sew broad seams or welts in a web-like manner, the
peculiarity of this improvement being that beside the ordinary needle-thread and
shuttle-thread, two catchers and two so-called chain-threads are employed for the
formation of loops. The said chain-threads lie at the edge of the seam, are changed
cross-wise with each other and at the same time two catch-threads are inserted, one
above, the other below the cloth, and sewn fast by means of the needle thread and
shuttle thread.
Referring to the accompanying drawings the improvements consist of
1) The needle A, which works in the ordinary manner combined with a catch or
with a shuttle, Fig. 7.
2) The two catches a and a¹ provided with eyelets i Figs. 6 and 12 and swinging in
a horizontal plane in such a manner, that the cloth or stitch-plate 6 lies between them,
this plate being for this purpose made hollow in its lower part Figs. 3-13. The
catches a a¹ are set in oscillation on their axles by means of suitable mechanisms, such
as the curved muffle situated on the axle B, with levers D, E and driving rod F,
Fig. 1.
3) The chain-thread-guides 9 g¹ which are alternately moved up and down so that
the chain-threads h form with every stitch a thread-cross into which the catches
introduce their threads above and below the cloth. The chain-thread-guides
consist of the kneed and pointed parts g, and g¹ which are guided with their supporting
rails d, Fig. 1, at the arm of the machine and moved alternately up and down by the
action of the angle lever D moved by the curve e and of the lever Figs. 6-13.
The spools G and G₁ Figs. 1 and 2 deliver the threads for the catchers a a¹, the
spools Hand H' those for the formation of the chain and spool J supplies the thread
for the needle, while the shuttle carries a spool in itself.

page_text: The said mechanisms work as follows:-
The formation of the commencing stitches being supposed, and the needle A
beginning to descend (Figs. 6 and 7) the catches a and a¹ are situated with their
threads in their extreme position behind the needle, which at this moment stitches in,
so that on return of the catches, the threads and remain hanging behind the
needle Fig. 9. In this position the catches a a¹ have at the same time brought their
threads and through the cross formed by the chain-thread-guides 9 and g¹.
Subsequently the thread-guides g and g³ change their situation i.e.-g¹ rises and
descends Fig. 10, the catch threads
being thus bound in by the formation of the
cross. At the same period the needle ascends and sews with the shuttle thread m
the two catch threads 71 on to the cloth. Now the catches commence to return
to their extreme position behind the needle, while the needle assumes its highest
position and the cloth is displaced. Subsequently the needle A commences
again a stitch retaining again the threads and A brought by the catches behind
the next stitch-hole, Figs. 12 and 13. The catches a a¹ then proceed again uniformly
and pass the thread-cross; the chain-guides change and the needle again stitches
fast the catch threads so that a row of loops is produced as shown by Figs. 14-17
To work strong cords into the edge of the cloth, only one chain-thread-guide is
employed instead of two, which guide is moved up and down, whereby a simple
looping in of the thread and of the catch-threads is produced, the loops being
formed as shown in Fig. 18.
For the purpose of tightening each single loop n Fig. 19 of the catch threads by
thread-cross, the thread guides may be caused to change twice during one stitching
period, whereby loops as shown in Fig. 19 are produced.
The improved mechanism may be applied to any system of sewing machines.
Having now particularly described and ascertained the nature of my invention
and in what manner the same is to be performed, I declare that what I claim is :—
In sewing machines, the arrangement of mechanisms for producing the web-like
sewing of seams or welts consisting in sowing fast the threads delivered by catches a a'
made to swing below and above the cloth, by means of the needle and shuttle thread,
these catch-threads being besides bound to the edge of the cloth by threads supplied
by chain-thread-guides, moved alternately up and down, the whole substantially as
illustrated and described and for the purposes set forth.