Year: 1887

page_text: Date of Application, 29th Apr., 1887
Complete Left, 12th Dec., 1887
Complete Accepted, 13th Jan., 1888
We EDWARD KOHLER and MORRIS LACHMAN, both of Fore Street in the City
of London, do hereby declare the nature of this invention to be as follows:-
This invention rolates to that class of sewing machines in which a single thread for
the production of a chain stitch is used, the principal objects of the invention being
to obtain an increase of speed of working, simplicity of mechanism, and also to
improve the strength and quality of the sewing. By these improvements, the length
of the needle loop will be less than is required for loopers of the ordinary construc-
tion, thereby avoiding, to a great extent, the friction of the thread in the eye of the
needle, occasioned by the take up, and consequent liability to breakage.
In carrying out this invention, we employ a reciprocating needle formed with an eyo
to receive a thread, and a rotary looper of novel and peculiar character. This looper is
nearly annular in form, in length about of a circle, pointed at one end, and gradually
increasing in thickness or width towards its heel, which is forked. This annular looper
is mounted in a carrier immediately below the table of the machine, such carrier con-
sisting of two cases, cups, or discs, suitably recessed on their inner faces to receive the
looper, and pressed together by a spring or springs. Rotary motion is given to the
annular looper through a shaft, onto which the carrier is secured in any convenient
manner. This looper is so situated that its point will cross the vertical line of the needle's
vibration at right angles, and close to the underside of the table, and it will take the loop
of the needle thread presented to it, retain it while the needle rises and the feed of the
work takes place, and then present the opened out loop for the passage of the needle
through it at its next descent. The heel of the looper then leaves the loop on the needle
stem, its point immediately entering the next loop. By successiv erotations, a series of
chain stitches will be formed at high speed, without weakening the thread by
unnecessary friction through the eye of the needle.

page_text: Improvements in Sewing Machines.
We EDWARD KOHLER and MORRIS LACHMAN, both of Fore Street, in the City
of London, do hereby declaro 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 that class of sewing machines in which a single thread for
the production of a chain stitch is used, and it provides for the conversion, when so
desired of certain lockstitch or two-thread machines into single thread or chain stitch
machines, the principal objects of the invention being to obtain an increase in the
speed of working, simplicity of mechanism, and also to improve the strength and
quality of tho sewing.
By these improvements the length of the needle loop in chain stitch sewing will be
less than is required for loopers of the ordinary construction, thereby avoiding to a
great extent the friction of the thread in the eye of the needle, occasioned by the
take-up, and consequent liability to breakage.
Our invention is applicable to various constructions of sewing machines in which
a horizontal shaft is provided below the table for operating the rotary hook or
looper.
The driver carried by this shaft wo utilize to drive, or modify it to adapt it to drive,
a loose hook or looper of peculiar construction.
This looper works in a fixed circular race, in front of which the vertical needle
vibrates, to present its open loop to the nose of the looper.
Wo have not considered it necessary to show our invention as fitted to a single
thread sewing machine, because the only change necessary for its adaptation
thereto is the fitting of the ordinary looper shaft with a suitably shaped looper
driver.
The rotation of this looper will be continuous, and no change will be required in
the timing of the reciprocating needle or in the timing of the feed.
Our improved looper is nearly annular in form, its perimeter extending over rather
more than three quarters of the circle. The nose of the looper is pointed, and its
heel is forked for the purpose of providing a space for the needle to pass into within
the plane of rotation of the looper, in order to take the last formed loop from the
looper. The rotary hook or looper is secured in its circular race by a retaining ring,
which fits an annular rebate in the face of the race, and the race wo preferably form
in one with the front bearing of the shaft upon which the looper driver is
mounted.

page_text: In the accompanying drawings,
-
Figs. 1 show the rotary hook or looper in sido, plan, and edge views, constructed on
a scale to take loops of twine, such as is used in sewing sacks.
Figs. 2 shew the looper, its race, and driver in elevation and in sectional plane, the
ring which retains the looper in its race being removed in the elevation to shew the
looper more clearly.
Fig. 3 is a sectional elovation of the rotary hook or looper and its race, taken in tho
plano of the axis of the driving shaft.
Figs. 4 shew the driver detached, in side and edge views.
Figs. 5, 5, 6, 6, 7, 7, 8 and 9 show the needle, the looper, and its driver in the
successivo positions which they take up during the for mation of a stitch, the looper
being represented in side view at Figs. 5, 6, 7, 8 and 9, and in plan at Figs. 5° 6ª
and 7.
Referring now to Figs. 2 and 3, A is the loose hook or looper, set in its race B,
which is made fast to the framing C of the machine.-D represents a horizontal shaft,
on the end of which the driver E is mounted.-The driver and the looper aro so
shaped with respect to each other as to provide for a loose interlocking of the parts, a
slight play being allowed to provide for the free passage of the thread between them.-
F is the ordinary vertical eye-pointed needle.-G indicates the table for supporting
the work, which may be fed forward in the direction of the arrow, Fig. 6, either by a
top or under feed device. The form of the hook or looper A is peculiar, and will be
best understood by referenco to Figs. 1.-The nose a of this looper is bent outwards
to meet the needle on its descent and pass through the loop which the needle has just
brought down through the work and presented to the looper.-The tail end of the
looper is forked to provide an opening for the descent of the needle through it.---The
outer prong a of this fork is by preferenco made somewhat shorter and narrower
than the inner prong a², for the purpose to be presently explained. The breadth of
the looper is, as will be seen, gradually increased at the tail end, and it thereby serves
to spread the loop as the looper, in its rotation, passes through it.-An opened loop is
thus presented to the point of the needle at each succeeding descent of the same, for
the purpose of enabling the needle to take up the loop as the tail of the looper
leaves it.
The face of the looper is rebated to permit of its lying close against the retaining
ring B', which is shown in place, at Fig. 3, as secured to the race by screws, and
detached, in side and edge view, at Figs. 3*. The driver E, shewn detached at
Figs. 4, is so shaped as to form with the race a bed for the hook or looper A.
The extremity of the driver strikes the tail a³ of the looper, and causes it to
revolve in its race, but leaves the looper free to yield to the drag of the loop, and
thereby leave room for the loop to escape from the tail of the looper.
We have said that the prongs a¹ a² are of different lengths; this provides for the
loop leaving the looper gradually, the needle, in its descent, taking up the slack as the
thread escapes from the prong a', thereby commencing the operation of tightening
the stitch before the loop finally escapes from the tail of the looper.-The Hange of
the race B is recessed, as at b, to provide free play for the descending needle and
for the escape of the loop from the looper.-To provent the loop being caught by
the angle of the recessed flange, an adjustable piece is provided, as at b₁, which
overlies the recess, and guides the escaping loop out of the race when being
drawn up to tension.-This adjustable piece b is shewn detached, and in plane, at
Fig. 4*.
We will now explain the action of the mechanism, reference being had to Figs.
2. 5. 6. 7. 8 and 9.
Fig. 2 shows the needle raised from its lowest position, and presenting a loop to
the hook or looper, the nose of which is just entering the loop.
Fig. 5 shews the nose of the looper fairly through the loop.
Fig. 6 shows the position of the parts when the needlo has risen to its highest
position and tightened the stitch. At this time, the looper has passed halfway

page_text: through the loop, and the broad or forked part of the looper is now presented
to the loop, for the purpose of opening it out and presenting it to the needle.
Fig. 7 shows the position of the parts after the feed has taken place, the looper
holding the opened out loop in an inclined position, ready for the descending
needle to enter it, and carry through the next succeeding loop for presentation to the
nose of the looper.
Fig. 8 shows the loop in the act of escaping from the prong a¹ of the hook or
looper, the needle having descended to a position for taking up the slack.
Fig. 9 shows the position of the parts when the looper has passed through the
loop, and the pull of the descending needle has drawn the loop from the longer
prong a² of the looper.
The return movement of the needle next opens out a loop for the looper to
take up, which will be effected by the continued action of the driver bringing
the nose of the hook or looper into the position shown at Fig. 2, when the opera-
tions above described will be repeated. The completion of the stitch, it will be
understood, is effected by the rise of the needle to the position of Fig. 6 while
the last formed loop is retained upon the looper.
It will be seen that the tail end a² of the looper, and the shoulder e of the
driver, are severally rounded off; this facilitates the passage of the escaping loop
from between these two contact surfaces.
In adapting our invention to lockstitch machines which have a rotary hook
driver below the table, say, for example, the Wheeler and Wilson sewing machine,
we modify the form of the hook as shown at Figs. 10, and thus enable it to take
the place of the hook which throws the locking thread into the loop of the needle
thread.
To illustrate the adaptation of our invention to a lockstitch sewing machine,
we have shown in front elevation, at Fig. 11, and in side elevation at Fig. 12, a
Wheeler and Wilson sewing machine with an arrangement of tako up for the needle
thread which we find desirable to use in order to ensure the efficient action of the
rotary hook or looper. The race B remains unchanged, and also the driver E, but in
order to enable the driver to take a proper hold of our improved hook or looper, we
form two shoulders on the hook, as at a³ a¹, corresponding to the shoulders of the
ordinary hook which the driver was designed to rotate.
The timing of the movements of the vertical needle, the driver, and the feed dog,
remain unchanged, but the threading up of the machine is somewhat different. We
do not however disturb the arrangement of the machine as constructed, and sold, but
wo apply to the head of the machine a fixed fork H, carrying two eyes 1, 2, through
which the thread drawn down from the ordinary tension apparatus is passed.
From the eye 2 the thread is led to the eye of the needle F. The needle bar is
provided with a finger 3, which plays up and down (as the needle is operated) within
the fork, and below the horizontal portion of the thread stretched between the eyes
1 and 2 of the fork. As, therefore, the needle rises to tighten the stitch last formed,
the finger 3 will take up the slack of the thread, and thereby ensure the proper
action of the needle upon the stitch.
The book A, Figs. 10, it will be understood, acts in a precisely similar manner to
the hook of Figs. 1.-It will not therefore be necessary to repeat the explanation
above given with reference to the diagrams Figs. 5 to 9.-It will suffice to say that
when the hook A replaces the loose hook of the lockstitch sowing machine of which
the Wheeler Wilson machine is taken as a type, the sewing of a scam with a single
thread will take place in such machine in precisely the same manner as it would in a
machine built for the purpose of sewing with a chain stitch.
When it is desired to resume the lockstitch sewing, it will only be necessary to
remove from the race the hook or looper A, and replace it by the hook and thread
case constituting portions of the original machine, and then to thread up the machine
as before, putting out of use, for the time being, the take up just described. The
machine may then be worked as if no change had been effected in it.

page_text: Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what we
claim is 1
1. The loose rotating hook or looper A, consisting of an open ring, one end of
which is pointed to take the loop of the needle thread, while the other end is
forked to open out the loop, such hook or looper passing endwise through the loop of
the needle thread, retaining the loop until opened out and presented to the descending
needle (to be entered by it), and then releasing the loop, whereby the liability of
making missed stitches in single thread chain stitch sewing, is effectually removed.
2. In sewing machines provided with a horizontal driving shaft below the table, and
fitted with a suitable driver, the loose looper A supported in a circular race B, and
working in combination with a reciprocating eye pointed needle F, for producing
chain stitches with a single thread.
NEWTON & SON,
Agents for the Applicants.