IMPROVEMENTS IN SEWING MACHINES
Year: 1886

page_text: I, NEWNHAM BROWNE, Fellow of the Institute of Patent Agents, of 73, Cheapside,
in the City of London, do hereby declare the nature of the said invention for
"IMPROVEMENTS IN SEWING MACHINES (a communication to me from abroad by
Edward Frankenberg of Hanover, in the Kingdom of Prussia, German Empire) and
in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:-
The invention hereinafter described is applicable to sowing machines of any of
the ordinary systems but more especially to double lockstitch sewing machines.
It has for its object to permit a stitch of any desired length to be made in any
direction. A machine embodying, this invention therefore permits the material
passing through it to be moved away from the needle point in any direction (i.e.
forward backward or to the right or the left indifferently) during the time the
machine is at work, and this without requiring the material to be turned about
and without injury to the needle, the thread, the material or the formation of the
stitch or the locking thereof.
This enables the double-lockstitch to be transformed into a flat embroidery stitch
of any desired length and this could not be done by sewing machines arranged and
constructed as heretofore customary because in such machines the presserfoot and
feed motion allow only a slight movement of the fabric passing through, and even
if the presserfoot and feed motion are thrown out of gear, a long stitch (say up to
100 millimeter) would cause the thread to be broken or the needle to be bent or
broken:
:
: The present invention however admits the production of a stitch of very con-
siderable length in any direction without injury to the thread or to the needle &c.
Thus the double lockstitch is transformed into the flat stitch which is of such great
importance in the production of embroidery. This does not entail any alteration
of the machine as a whole, the systein of its construction, viz. the formation of the
stitch, remains unaltered. By simply adjusting a single screw the novel mechanism
hereinafter described may be made inactive and the machine will then work as an
ordinary double-lockstitch machine in which the length of stitch is limited by the
operation of the presserfoot and clothi-feed.
.

page_text: In order to obtain the said flatstitch by means of a double-lockstitch machine
the following are requisite.
1) The presserfoot which hitherto remained immovable during the formation of
the stitch, must receive such a movement that it will hold the fabric fast only at
that time when the shuttle seizes the thread for the formation of the loop but will
release the fabric during the remaining parts of the up and down motion of the
needle so that during these parts of the needle-motion the fabric may be moved in
any required direction. Hitherto the sewing could be done in one direction
(relatively to the needle point) only as the feed motion carried the fabric away
from the needle in one direction only that is to say in the direction of a single
straight line When it is desired in an ordinary machine to produce a curved seam
or a seam forming a right angle or any other angle it is requisite so to turn the
material about the needle that the line so to be followed by the seam may be
brought forward of the needle and the fabric be fed to the needle in the direction
in which the feed motion works! These inconvenient movements which heretofore
were necessary for sewing backwards sideways or in other varying directions are
entirely obviated by the present invention.
2) The tension of the thread has to be regulated in such a manner that the
requisite quantity of thread be available for stitches of any desired length so that
breaking of the thread or bending of the needle may be entirely obviated.
3) The cloth feed must be put out of action.
4) The novel mechanism must be capable of being thrown out of gear or of
being rendered inactive by a simple and rapid manipulation, so that the machine
works as an ordinary sewing machine with double lockstitch.
"
In order to fulfil the first requirement the movement of the presserfoot say on a
Singer" machine, an intermediary piece, a lever, is provided on the head and the
heart shaped cam is transformed into an eccentric which 'in connection with the
said lever keeps the presserfoot raised whilst the needle is outside the throat or
hole of the needle plate so that consequently no pressure is exerted upon the fabric
during that time.
For fulfilling the second requirement the heretofore usual single thread-lever is
replaced by a two armed thread-lever in connection with a second sewing-thread-
tension-roller These cause that, whilst the needle rises à quantity of thread is
drawn off by the double (two armed) thread lever which is sufficient for the desired
length of stitch whilst at the same time sufficient tension is put upon the thread
thus preventing the breaking of the thread whilst also securing the proper locking
of the stitch.
For the purpose of allowing the fabric passing through the machine to be moved
in any desired direction the cloth feed is rendered inoperative by the withdrawal of
the wedge by which it is raised and thus the cloth feed can no longer act upward.
The principle of construction of machines to which the present invention is
applied is not altered and they become applicable as ordinary double lockstitch
sewing machines by simply tightening a single screw thereby rendering inoperative
the intermediary piece or lever by which (in connection with the eccentric) the
movement of the presser bar, and consequently of the presser foot is caused, the
presser foot will then press upon the fabric in the usual manner and the cloth feed
becomes operative.
i
By these improvements the most varied kinds of work in floatstitch can be
rapidly and exactly executed on a double lockstitch machine and even upon
machines of other systems.
"
In order to render the improvements above referred to and the manner in which
they may be carried into effect readily intelligible, their application to a "Singer'
machine is hereinafter described and illustrated in the annexed drawings in
which:-
Fig. 1. is an elevation of the head of the sewing machine that is to say of the
front part of the upper portion of the machine.
The

page_text: Fig. 1b is a vertical section on line a. a. fig. 1, similar to fig. 1a but showing the
position of the screw in which the machine is transformed into a double lock stitch
nachine working in the usual manner. Fig. 2 is a side elevation of fig. 1.
Fig. 3, is a front view of the head with the casing of the needle bar and presser
ar removed showing the needle bar and presser bar in the position which they
ssume when the needle is at the top of the stroke.
Fig. 3 shows in elevation the position of the needle bar and presser bar fig. 3.
Fig. 4 similar to fig. 3 with the needle bar and presser bar in their lowest
position.
Fig. 9, front and side elevations of a second modification of the heart shaped
cam-disc or eccentric.
"
As already mentioned the system of construction in the present example there-
fore that of the "Singer double lock stitch machine remains unaltered. The
motions of the needle and shuttle and the formation of the stitch therefore remain
the same. For this reason the lower parts of the machine and the formation of the
stitch are not represented in the accompanying drawings.
I
The presserfoot D. hitherto remained immovable during the formation of the
stitch now in order to cause it to press upon the fabric whilst the shuttle seizes the
thread in order to form the loops and to maintain it raised during the remaining
period in which the needle rises and descends the heart shaped cam disc S which
hitherto has been made circular in outline, is made with an excentric curve as
shown in figs. 3. 4 and 8. 9. From this results that the intermediary lever H. (freo
to turn on the screw k, in the head K.) will during one part of the movement of S,
that is whilst the shuttle seizes the thread for the loop not be affected by the disc S
that is to say the upwardly curved end h¹ of the lever H can not be depressed by
the disc S. The other arm h² of the lever H acts upon an adjustable pin d screwed
into the presser bar D. in the following manner.
The usual coiled spring f with which the pressbar is fitted always tends to
depress the presser bar D. that is to say presses it against the fabric passing
through the machine. The presserfoot continues to bear upon said fabric until the
portion m n of the periphery of the excentric disc presses upon the arm h of the
lever and causes the other arm h² to raise the pin d and consequently the presser,
bar D' thus causing the presserfoot D. to release the fabric (see figs. 3, 3 and 1º).
In continuing its rotation and until a revolution is completed the periphery of
the cam or excentric disc S no longer acts upon the lever arm h¹ and the coiled
spring f. depresses the presserbar D₁ and the presserfoot bears upon the fabric (see
fig. 4).
The front part of the presserfoot itself is shortened so that the needle descends
in front of the presserfoot and is not interfered with by the presserfoot.
The following are means for carrying into effect the second requirement above
referred to viz the regulation of the tension. The thread tension lever is made
with two arms F2 and F¹ instead of having one arm, F¹ only; it is pivoted in t.
Moreover besides the tension roller B' upon the head, viz on the front of the needle
bar casing A, a second roller B is provided on the side of the head K. (see figs. 1
and 2, 5 and 3). In this manner the tension of the thread is in connection with
the two armed lever F² so regulated that the arm F1 will draw off thread when the

page_text: needlebar N. descends as well as the arm F" which draws off thread when the
needlebar rises.
The sewing thread (namely that passing through the needle) is guided as
follows: From the spool R it passes through the eye of the lever arm F' then
along the tension roller B³ to the guide-eye a and thence to the tension roller Bt
the eye of lever arm F¹ and through the apperture n of the needle-tension device
and through the needle N.
It will be seen in figs. 1 and 2 that when the needle is in motion that portion of
the thread which is between F2 and B' will be slackened whilst the portion
between B and F¹ is drawn taut (see the full line in fig. 1 and 2) and when the
needle descends the part between B¹ and F¹ is slack and the portion between B*
and F is taut (see dotted line in figs. 1 and 2) so that not only will sufficient
tension be put upon the thread to enable the stitch to be properly formed but a
quantity of thread sufficient for any desired length of stitch is also provided by the
lever F¹ F
As already mentioned the freed motion is inoperative when the machine is used
to work flat-stitch, and this combined motion of the presserbar and of the thread
feed allows the stitch to be laid in any direction, whether forward backward or
towards any side, without requiring the fabric to be turned, whilst any length of
stitch may be made as sufficient thread is always fed.
If the novel mechanism is to be thrown out of action in order to enable the
machine to make the ordinary double-lockstitch (for which purpose the cloth feed
is again thrown into gear or made operative) it is only required to turn the stud
or pin d (screwed into the presserbar D¹ and acted upon by lever H.) fig. 1ª
until the said stud is screwed back so far as to lie entirely within the presser-
bar D. It is then out of gear and the presser foot bears upon the fabric during
the motion of the needle bar and the formation of the stitch, in the usual manner
which is well understood.
In figures 8 to 8° and 9 are shown modifications of the suitably shaped excentric
disc "S." The first Figs. 8 to 8° consists in not cutting away the circular cam or
disc as shown in figures 3 and 2 but simply taking off half the thickness from the
periphery of S¹ from the point m¹ to n¹ on the rear surface (the lined portion 8¹ in
figure 8b) whilst in the second modification figure 9 the depression of the arm h¹
of lever H is provided by an enlargement of the circular disc S' at its periphery
between the points m² and n³ so as to make it an cam disc (Figure 9 only shows
the dotted outline of the enlargement).
A further improvement relates to the means for fixing the screw of the tension
roller see figures 5, 5º, 5b.
Heretofore the screw "C" of the tension roller B' which is regulated by means
of the set screw G and spring E, has been adjusted by the befurcated end e of the
spring E and an annular grove in b into which e takes. This does not prevent
rotation of C when adjustment is effected by the nut B. According to this part
of the present invention however the annular grove 6 is replaced by two flat
surfaces 61 61 produced on b say by filing and the fork e engages these and this
entirely prevents rotation of C.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I wish it to be understood that what I claim is,
(1.) A sewing machine adapted to the production of both "flat stich" (that is to
say stiches of any length and in any direction without requiring the fabric to be
turned round the needle) and of ordinary stitch as may be required substantially
in the manner and by the means herein above set forth and illustrated in the
Drawings.
(2.) In a sewing machine for making flat-stitch the arrangement of the lever H
in combination with a cam disc or excentric (such as S, or as S¹ or S²) and with an
adjustable stud or screw "d" provided on the presser bar, the whole arranged for

page_text: enabling the presser foot to press upon the fabric only at the moment when the
shuttle seizes the thread for the formation of the loop, the said presserfoot being
raised during the remainder of the needle-motion, all substantially as and for the
purpose set forth and as illustrated in the drawings.
(3.) In a sewing machine the arrangement comprising the two armed thread-
lever F F in combination with the tension rollers B¹ B' for the purpose of
providing sufficient thread at the proper tension for any requisite length and
direction of stitch substantially as specified.
(4.) In a sewing machine capable of producing flatstitch or other stitch as desired
the adjustable stud d screwed into the presser bar the withdrawal whereof into the
presser bar disengages the lever H enabling the fabric to be fed in the usual
manner.
(5.) In a sewing machine such as described the cam or excentric constructed
substantially as shown in figures 8 to 8° and 9 and having the periphery either
reduced in thickness at the part m¹-n¹³ or enlarged at m²-n² said cam serving to
actuate the lever H and the presser bar, substantially in the manner and for the
purposes set forth and illustrated in the drawings.
(6.) In sewing machines the arrangement as specified with reference to figures 5
to 5b for obviating the rotation of the screw stud b' of the tension roller when the
tension is adjusted by the nut "C" said arrangement consisting in the substitution
of the two flat surfaces 6' 6' for the annular groove with which the fork e engages.
Dated this 25th day of June 1886.