IMPROVEMENTS IN SEWING MACHINES
Year: 1870

page_text: PROVISIONAL SPECIFICATION left by Carl Necker at the Office of the
Commissioners of Patents, with his Petition, on the 30th March
1870.
I, CARL NECKER, of Berlin, in the Kingdom of Prussia, Merchant, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
SEWING MACHINES," to be as follows:-
Figure 1 is a plan; Figure 2, a side view; Figure 3, a back view;
Figure 4 is a front view of my improved machine. The remaining
Figures shews details and modifications of my Invention.
By these improvements I obtain a construction which varies entirely
from those used hitherto, and I am therefor able to make a perfect and
elegant mantua-makers' hem, which is sewed not only by two threads,
but also by one thread, herein-after described. By means of the belt
pulley Ga turning to the right-hand, the driving shaft G with the three
eccentrics Gb, G c, G d, placed on it will move, and through them the
whole mechanism is caused to operate. The eccentric Gb effects the
movement of the fabric S by means of the cylinders Fa and Ec
revolving from the right-hand to the left. The eccentric Gc effects the

page_text: horizontal motion of the needle bar II, and the motion of the spiral
shaft F, which is parallel with the needle bar and operates the circular
thread taker Fb.
In order to fully comprehend this motion it must be understood that
the circular thread taker Fb is moved by the bevelled spiral shaft F, and
the latter by the conducting slit Fa of the fork II a fixed on the needle
bar H. The eccentric Gd effects the circular reciprocating motion of
the angular thread takers N and O for sewing both with one and with
two threads.
For producing the mantua-makers' hem according to my Invention,
which is made with one thread, it is necessary that the needle P, the
angular thread taker N (without an cyc), and the circular thread
taker F 6 shall operate in the following manner :-Before motion is given
to the machine the fabric S (which may be cloth, leather, or other
material) is squeezed between the aforesaid cylinders or fabric guides
Fa and E c. Motion is then given to the machine and the needle P
carries the thread through tho fabric S. Now the thread No. 1 carried
through the fabric becomes a loop after the needle P has been slightly
withdrawn. This loop is taken up by the angular thread taker N and
carried to the necessary height. At this moment also the circular thread
taker Fb takes the loop (Figures 5, 8, 11,) by what means the loop will
become larger and more round. This loop drawn in the manner described,
but kept by the two thread takers N and Fb permits the needle P, which
again moves forward to pass through this loop without hinderance. As
soon as this operation has taken place the two thread takers N and Fb
remit the loop and the latter is disengaged from them. The loop now
becomes firmly fastened. In this manner the stitch which forms with
one thread the mantua-makers' hem and the draw stitch are effected.
The mantua-makers' hem of two threads, which can also be sewed
with my machine, is obtained almost in the same manner, only the
following changes take place. The angular thread taker N, which was
necessary for the mantua-makers' hem is replaced by the angular thread
taker O (with an eye). The thread No. 2 unwound from the thread
spool placed upon the spool pin R is carried under the tension K
(Figures 1, 2, 3, 4,) then through the bevelled slit L' of the thread
adjuster L, then through the eye T placed on the guide D6 of the
angular thread taker, and finally through the two eyes V¹ and V
(Figures 11, 12, 13,) of the angular taker O, in such manner that the

page_text: end of the thread after having run at first through the eye V' on the
elbow is carried along the thread groove, and finally out through the
eye V placed on the point. After the needle P having penetrated
through the fabric the angular thread taker O takes up the above
described loop (Figures 5, 8, 11,) and draws it to the elbow. In the
meantime the angular thread taker O has attained its necessary height,
and the circular thread taker Fb takes the thread No. 2, carries it
downwards, and the needle P moves without hinderance through the
loop of the thread No. 2 formed by the circular thread taker; thus the
mantua-makers' hem with two threads is formed.