Improved Sewing Machine with Mechanically Actuated Crank Mechanism for Braiding and the like purposes.
Year: 1898

page_text: Date of Application, 8th Mar., 1898-Accepted, 30th Apr., 1898
COMPLETE SPECIFICATION.
Improved Sewing Machine with Mechanically Actuated Crank
Mechanism for Braiding and the like purposes.
We, DAVID NADEL and HEINRICH HERZBERG, both of Spindlershof, 4, Seydel-
strasse, Berlin, in the German Empire, Manufacturers, 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:-
Our invention relates to a sewing machine with crank mechanism for braiding
and the like, having a mechanical actuation of the crank.
In all constructions of sewing machines with crank mechanism for this purpose
hitherto known, a serious drawback consists in that the crank mechanism is
actuated by hand, and consequently the correctness of the pattern obtained depends
always on the skill of the worker. As, however, even the most skilled workman
in spite of having the pattern before him is liable to be disturbed by other in-
fluences whilst guiding the crank by the hand, as for instance, if he looks up from
the work, consequently this method of actuating the crank mechanism by hand
has a distinct drawback in the manufacture of certain goods.
Our invention is designed to obviate this drawback, and we attain the object
by causing the motion of the crank by mechanical means, so that the same is com-
pletely dependent upon the pattern to be produced. The motion must of course
be a different one for each different pattern.
This method of actuating the crank mechanism is attained by connecting the said
crank by means of suitable intermediate parts (guide rods and a double lever)
with a cylinder or an eccentric, the surface whereof is provided with curves,
so arranged that when the said cylinder or eccentric is revolved, a point in connec-
tion with the said double lever engages therein, and causes the corresponding motion
of the crank which is required by the pattern in question. Moreover, in hand work
the crank mechanism must be sometimes more quickly, sometimes more slowly
actuated, or it must be caused to move forwards or backwards or even at certain
moments be held stationary according as a looped, or zig-zag, or wavy, or straight
pattern is to be produced. It is obvious therefore that in the mechanical actuation
of the crank mechanism, the revolution of the cylinder must take place, some-
times slower, sometimes quicker, sometimes forwards, and sometimes backwards.
These variations are rendered possible by the arrangement of the cylinder
eccentric provided with the aforesaid curved grooves in that during the revolution
the double lever is always caused to move more quickly when the point actuating
it passes over a very much inclined portion of the groove, whilst on the other
hand it will move more slowly, and consequently cause the crank to turn slower
when the curve on the cylinder is less oblique.
or
In the accompanying drawing our invention is illustrated in the form specially
designed for use as a crank actuated sewing machine for the sewing on of braids
and the like. In this drawing
Figure 1 shews the arrangement in plan
Figure 2 in elevation together with a portion of the machine, whilst

page_text: Figure 3 shews a side view of the invention itself.
To the crank a which effects the revolution of the shaft b, whereby the thrust-
ring of the machine surrounding the needle is actuated in the usual manner,
there is attached the rod c secured at its other end to the double lever d. By
the motion of the said double lever in the one or the other direction the turning
of the crank will obviously be effected. As the crank as already stated is re-
quired to turn sometimes slower, sometimes quicker, and in certain cases must
even remain stationary, or go backwards it is obviously necessary that the motion
of the double lever when the machine is at work must be correspondingly affected.
This object is attained by providing the same at its shorter end d' with a point
or sliding piece engaging in a groove e of the cylinder g. This groove e is
formed more or less curved according as the crank is required to move quicker
or slower, and it must in order to produce a recurring pattern of course be joined
together at its ends upon the circumference of the drum. This condition can
be easily attained by choice of a suitable diameter for the drum. If the crank
is required to stand still the curve becomes a straight line, whereas a turning of
the crank is caused as soon as the said line again takes an inclined position to
the perpendicular plane of the drum.
Our invention is described by way of example with application to the braiding
industry, for which this invention is of especial advantage, because by it the
opportunity is afforded of having all like patterns executed exactly alike, and
independently of the skill of the workman.
said
Having now particularly described and ascertained the nature of our
invention and in what manner the same is to be performed we declare that what
we claim is ;-
-
1. The improved sewing machine with mechanical actuation of the crank
mechanism characterized by the arrangement that the said mechanism is connected
by means of intermediate parts with a cylinder or an eccentric in such manner
that the said drum or eccentric constructed to correspond with the design to be
worked will correspondingly actuate the crank mechanism to produce the required
pattern.
2. In a sewing machine for braiding and the like, the combination of parts
forming the improved mechanical crank mechanism substantially as described and
illustrated in the accompanying drawing.
Oil
J
e r
1
1000
W. P. THOMPSON & Co.,
322, High Holborn, London, W.C., Patent Agents for the Applicant.