Improvements in Sewing Machines.
Year: 1891

page_text: Date of Application, 19th May, 1891
Complete Specification Left, 19th Feb., 1892-Accepted, 9th Apr., 1892
PROVISIONAL SPECIFICATION.
Improvements in Sewing Machines.
1, ANNE SIEBERT, of 80 Wienerstrasse, Darmstadt, in the Empire of Germany,
do hereby declare the nature of this invention to be as follows:-
This invention has for its object to enable a double-thread lockstitch shuttle
machine to be temporarily converted into a single-thread chainstitch machine, and
it consists essentially in the combination, with the ordinary shuttle machine, of a
needle thread looper having a curvilinear reciprocating motion in a horizontal
direction transverse to the paths of the needle and shuttle and of a special shuttle
having at the point and heel blunt extensions of the face which works against the
shuttle race whereby the shuttle, instead of entering the loop of thread thrown out
by the needle as usual, pushes it aside and into the path of the thread looper which
then comes forward, catches it; and lays the loop in an approximately horizontal
and spread open position beneath the needle hole, in position for the needle to pass
through it at its next descent and so form the chain stitch.
The thread looper is a hooked finger on a plate fitted beneath the needle hole
plate, connected at the rear end with a rock lever actuated by a cam on the vertical
shaft of the machine and guided at its forward end by a stud moving in a curved
guide slot in the machine bed plate.
.
The point of the thread looper is slightly bent downwards, travels in a groove,
and is further shielded by a projection on the looper plate in advance of it whereby
the looper on its next forward motion is prevented from catching a second time in
the loop which it has just thrown off.
The extension at the heel of the shuttle serves to prevent the release of the loop
thrown out by the needle until the latter has moved upwards so as to ensure the
loop being properly taken and spread cut horizontally by the looper.
The needle hole is bevelled at the underside in the two directions in which the
loop is deflected by the shuttle and the looper respectively.
The looper is held out of action for ordinary lock stitching by a thumb latch
engaging with the rock lever through which the looper is worked, said lever being
held up to its actuating cam by a spring.
In order to convert a lock stitch into a chain stitch machine, it is only necessary
to release the thumb latch and substitute the shuttle with point and heel extensions
for the ordinary one.
The motion of the looper in a curvilinear path carries it clear of the needle path
while ensuring the loop taken by it being stretched in the direction of the line of
sewing, so as to ensure its being taken by the needle at its next descent.
Dated this 19th day of May 1891.
COMPLETE SPECIFICATION.
Improvements in Sewing Machines.
I, ANNE SIEBERT of 80, Wienerstrasse, Darmstadt, in the Empire of Germany,
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 has for its object to enable a two-thread lock-stitch shuttle

page_text: machine to be readily converted into a single-thread chain-stitch machine. This
object has been sought to be attained in many other machines, as for instance in
the machine of The Branston Two-Reel Sewing Machine Co., Limited, American
Post Machine, in the machine of Jeremiah Keit, German Patent No. 13658, also
in that of Edward Kohler, German Patent No. 55018, also The Patent Button-Hole
Machine Co., London. All these have many drawbacks, the chief cause of which
is the complicated and uncertain action of the mechanism, owing to which the
machines above referred to have not come into general use.
The present invention consists essentially in the combination, with the ordinary
shuttle machine, of a needle-thread looper having a curvilinear reciprocating motion
in a horizontal direction, transverse to the paths of the needle and shuttle, and of a
device working against the shuttle race and acting in lieu of the ordinary shuttle
whereby the loop of thread thrown out by the needle is pushed aside into the path
of the thread looper which then comes forward catches and spreads open the loop
and carries it beneath the needle-hole in such position that the needle will pass
through it at its next descent and so form the chain-stitch. The device whereby
the needle-thread is brought into the path of the looper is carried by the shuttle-
driver and may either be a permanent adjustable attachment thereto, or a special
form of shuttle, as hereafter described.
Reference is to be had to the accompanying drawings, forming part of this
Specification, wherein
Figure 1 is a plan with the needle-hole plate removed and the base plate broken
away.
Figure 2 is a vertical section on line - Figure 1.
Figures 3 to 5 shew the needle-thread looper in several positions (in Figure 3
the looper hook has just entered the needle-thread loop; in Figure 4 it has drawn
it forward; and in Figures 5 and 5 the loop of needle-thread is so held that the
needle will pass through it at the next stitch).
Figure 6 is a section on line y-y Figure 3 and Figure 7 a cross-section of
Figure 6.
Figure 8 is a section of the needle-hole plate.
Figure 9 is a top and face view of a special form of shuttle which may be used
in lieu of finger K.
Referring to Figure 6, the needle-thread is at each descent of needle a through
the needle-hole plate A pushed aside by a finger K pivoted on the shuttle carrier
and pressed lightly against the shuttle race by a spring c. By this means the
needle thread is brought into the path of the thread looper about to be described,
which then comes forward and lays the loop in such position that the needle will
unfailingly pass through it at its next descent and so form the chain stitch.
The needle-thread looper is a hook H on a plate B fitted to slide beneath the
needle-hole plate A, said plate B being connected at the rear end with a rock
lever D pivoted at E and actuated by a spring G and cam F on the vertical shaft
of the machine and guided at its forward end by a stud moving in a curved guide
slot C in the machine bed-plate. The hooked thread-looper H projects, as shewn,
at the side of the plate B and moves in such a path as to catch the needle-thread
loop spread open by the finger K and bring it around the needle towards the front
and hold it in such position with regard to the needle-hole that the needle will go
through it at its next descent. The old loop is then let go, and a new loop is
caught by the finger K, thus forming a chain-stitch. The needle-thread looper
plate B is so guided by the stud at the underside of its forward end working in the
curved slot C that the hook H will pass clear to one side of the needle and come
around in front of the needle hole so as to hold the loop spread open beneath the
needle-hole, so that the needle will pass through it on its next descent.
The point
of the thread looper H is slightly bent downwards and travels in a groove L and
may if necessary be further shielded by a projecting spur on the looper-plate in
advance of the looper (as shewn in Figure 5) whereby it is prevented on its next

page_text: forward motion from catching a second time in the loop which it has just
thrown off.
The needle-hole is not simply round, as usual, but is bevelled at the underside,
as shewn in Figure 8, in the direction in which the loop is pulled in order that the
loop may be well spread as near as possible to the surface of the needle-hole plate,
so that the looper will catch it and the needle will pass through it with certainty.
For ordinary lock-stitching the looper is held out of action by a thumb latch Q
engaging with the rock lever D and holding it out of contact with cam F and the
finger K is thrown back out of action. The machine can then work with a shuttle in
the ordinary way.
Instead of the finger K a special shuttle K1 (Figure 9) having at the point and
heel blunt extensions kk', and held in the shuttle driver like an ordinary shuttle,
may be used for the purpose of pushing aside the needle loop into the path of the
looper before described.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is;-
1st. In a double-thread lockstitch shuttle sewing machine, the herein described
combination of apparatus for enabling the machine to be converted at will into a
single-thread chain-stitch machine, consisting of a device carried by, or mounted on,
the shuttle driver and adapted to push aside the needle-thread loop as described, in
combination with a thread-looper adapted to catch said loop as described and so
guided as to bring the loop into such position that the needle will pass through it at
its next descent and form the chain-stitch as described.
2nd. In combination with the above mechanism, the needle-hole bevelled at the
underside as and for the purpose specified.
Dated this 18th day of February 180
ANNE SIEBERT,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.
ANNE SIEBERT,
By A. M. & Wm. Clark,
3, Chancery Lane, London, Chartered Patent Agents.