Improvements in Whip Stitch Sewing Machines.
Year: 1890

page_text: Date of Application, 12th Nov., 1890
Complete Specification Left, 12th Aug., 1891-Accepted, 3rd Oct.. 1891
PROVISIONAL SPECIFICATION.
Improvements in Whip Stitch Sewing Machines.
1, BERNHARD KÖHLER of Chemnitz in the Empire of Germany, Manu-
facturer, do hereby declare the nature of this invention to be as follows:-
The object of this invention is an appliance for rendering the working of whip
stitch sewing machines for hosiery noiseless even when the machine works at high
speed. To accomplish this purpose, I effect the movement of the horizontal needle,
of the catcher and of the circle needle by means of rigidly coupled circular cams so
as to dispense with the springs and curves hitherto employed therefor.
On the main shaft are mounted three circular cams for operating respectively the
horizontal needle, the thread catcher and the circle needle.
actuating the two cloth feeding discs is likewise mounted on said shaft.
An untrue disc for
The cam for working the horizontal needle is connected by a draw rod with the
crank of the rocking shaft, while another crank mounted on the other side of this
shaft is connected by a link with the horizontal needle rod, so that the said cam
imparts a horizontal reciprocating movement to the needle.
The cam operating the circle needle actuates between two sliding checks a curved
lever, which thereby oscillates about its fulcrum and imparts to the circle needle
attached to its free end, an oscillating movement. The circle needle either works
with a thread-if the known two-threaded whip stitch is to be produced-or it is
replaced by a circle catcher, if the machine is to work with one thread only. In
the former case the thread catcher presses the circle needle thread, and in the latter
case the thread of the horizontal needle so far down as to allow the latter to move
over the thread.
The thread catcher is secured to a lever which is so moved by the respective
cam with which it is connected by a short link as to remain for a long time raised
and descend only for a short moment.
The untrue disc mentioned above actuates a wheel mounted on the shaft of one
of the feeding discs by means of lever transmission in such a manner as to cause
aid wheel to be turned, by a clamping cheek engaging therein, for an angle
corresponding to the length of stitch to be produced, the said levers being
etermined in their movement by a crank connected with the stitch adjusting
echanism.
The return movement of the lever system is effected by a spiral spring con-
ecting the said clamping cheek with the machine frame, while a second clamping
heek held by a spring against a stationary pin prevents the return movement of
he said wheel. The movement imparted to this wheel is shared by the feeding
isc mounted on the same shaft, and through two toothed wheels mounted
espectively on this shaft and on that of the other feeding disc-also to the latter,
that the cloth clamped in between the two feeding discs is conveyed prior to
ch stitching of the needle for the length of the stitch to be produced.
In order to cause the gearing of the toothed wheels to be the same with the
wing of thin or thick material, the bearing of the second feeding disc is made
voluble about pivots, the elongated median line of which passes through the
int of contact of the toothed wheels.
A suitably placed spring presses on a lever connected with said bearing whereby
e two feeding discs are pressed together. The lever is connected by a draw rod
th a treddle serving to remove the feeding discs from each other by foot pressure.
Dated this 12th day of November 1890.

page_text: COMPLETE SPECIFICATION.
Improvements in Whip Stitch Sewing Machines.
1, BERNHARD KÖHLER of Chemnitz, in the Empire of Germany, Manu-
facturer, 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 whip stitch sewing machines for hosiery and has for its
purpose to render the working of such machines noiseless even with a great number
of revolutions. To accomplish this purpose, I effect the movement of the horizontal
needle, of the catcher, and of the circle needle by means of rigidly coupled circular
cams so as to dispense with the curves and springs hitherto employed therefor.
Thereby I can make 1200 to 1400 stitches pr. minute, while hitherto only 300
to 400 stitches pr. minute could be made with these machines.
The whip stitch sewing machines serving for sewing hosiery are moreover subject
to the inconvenience, that with thick fabric, the toothed wheels, by which the
feeding discs are in connection, do not gear so deeply as with thin fabric, which
drawback I remove as hereafter described.
Referring to the accompanying drawing,
Fig. 1 is a bottom view,
Fig. 2 a front view,
Fig. 3 a rear view,
Fig. a partial plan of the improved machine.
Fig. 5 shews the stitch-adjusting bolt, and
Fig. 6 the circular needle employed when sewing with one thread only.
On the main shaft a are mounted the three circular cams bed and the untrue
disc e serving to move the feeding dises t', cam 6 moving the needle n, cam & the
thread catcher hand came the circle needle g. Cam bis connected by draw rod /
with crank k¹ of the rocking shaft i, and crank likewise mounted on i is con-
nected by link with needle rod N, so that through cam 6 the needle n is given a
horizontal reciprocating movement.
Cam c acts between the cheeks g¹² on lever g³ which thereby swings about its
fulcrum and gives the screw g' and circle needle g an oscillating movement, said
needle either receiving likewise a thread, when the known two-thread whip stitch
seam is to be produced, or is replaced by circle catcher go, when one thread only
is used.
:
The catcher h so far presses down in the former case the circle needle thread,
in the latter case the thread of needle » as to allow the needle n to move along
above the same. This catcher is secured to lever ' which is so moved by cam d,
with which it is connected by a short link, as to remain above for a long time
and stay only for a short moment below.
The movement of slide wheels connected with feeding shaft 3 is effected as
follows by the untrue disc e by the aid of levers m m² m² m³ m² and of clamping
cheeks s¹ s².
Cam e presses lever m above to the right, Fig. 2, whereby m' is moved to the
left Fig. 5. The pin p' of crank p revoluble on the stitch adjusting bolt w
transmits the movement of lever arm m² to lever arm m³, and the lever arm m
brings the clamping cheek catching around the rim of slide wheels, into the
position shewn in Fig. 5, whereby s is turned for an angle corresponding to the
length of stitch. The backward movement of the lever system described above is
effected by spring v¹ secured to s' and to the frame of the machine. In order to
prevent slide wheels from participating in this rearward movement, a second
clamping cheek held by spring against the stationary pins counteracts the
backward movement of slide wheel s. The feeding shaft and feeding wheel t¹
participate in this movement of slide wheels, and wheels ¹² transmit the same to

page_text: the feeding shaft t and feeding wheel t², so that the cloth clamped in between t¹
and 2 is shifted on in the known manner for the length of stitch prior to every
stitching movement of the needle.
The bearing of shaft is revoluble about the pivots ¹, the clongated median
line of which passes through the point of contact of the pitch circles of toothed
wheels in order to cause the gearing of these wheels to be the same with thin
as with thick cloth.
Spring u presses on lever u connected with ", thereby pressing against t².
The draw rod u' secured to u leads in the known manner to a treddle not shewn in
the drawing, so that t² can be removed from ' by a pressure of the foot.
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:
A whip stitch sewing machine, in which, in order to attain a noiseless working
also with a large number of revolutions, the movement of the needle, of the catcher,
and of the circle needle is effected by rigidly coupled circular cams, and the movable
feeding shaft is revoluble about a shaft which lies in the line of contact of the two
pitch circles of the feeding wheels in order to have equal gearing with thick
and thin fabric, substantially as set forth.
Dated this 12th day of August 1891
BERNHARD KÖHLER.
By Huelser & Co.,
His Agents.