Improvements in Sewing Machines.
Year: 1893

page_text: Date of Application, 28th Feb., 1893
Complete Specification Left, 21st Aug., 1893-Accepted, 9th Dec., 1893
PROVISIONAL SPECIFICATION.
Improvements in Sewing Machines.
I, VICTOR WITTE, of 4 Newgate Street, in the City of London, Sewing Machine
Manufacturer, do hereby declare the nature of this invention to be as follows:-
This invention refers to improvements in sewing machines, whereby one or other
of three varieties of stitches may be produced by the same machine, namely a
lock-stitch of the ordinary type, a chain-stitch also of the ordinary type, and
a chain-stitch with a second locking thread therein, or as I may call it, a locked-
chain-stitch, and my invention further refers to improvements in the mechanism of
the same machine, whereby I obtain a more direct feed, a regular stitch, and
moreover, stitches which may be increased or decreased in length, according as
may be required, with an index whereby the machine may be caused to produce or
reproduce any particular size of stitch.
Sewing machines, arranged according to my invention, to produce either a
lock-stitch, chain-stitch, or locked-chain-stitch as desired, are provided with a
reciprocating needle bar, a thread take-up or supply arm, a presser foot, a looper
shaft, and a rotary looper mounted thereon, together with mechanism of any well
known or approved description for actuating these parts at proper times. The
needle thread passes from the needle spool through proper guides and tension,
through the thread supply arm by an auxiliary tension device (as hereinafter
described) and through the needle eye.
According to my invention, the looper, which is of disc form, is made to receive
a case containing a shuttle spool to carry the under thread, and I arrange the
mechanism so that this spool may be removed or replaced when desired, it being
retained within the looper by a carrying ring as ordinarily employed for such
purposes, mounted on a shaft in bearings on the base plate and retained in position
by a spring. This shaft has a knob which may be seized by the operator and
caused to bring the ring away from the looper, whereby the spool case with its
spool may be removed or placed in position as required. Upon the looper shaft I
mount two cams adjacent to one another to act upon an arm carrying the feed
jaw. This feed arm is pivotted at its rear end between two arms of a rock shaft,
the latter carried in bearings on the underside of the base plate. One cam gives a
rising and falling motion to the feed arm, and the other gives an advance motion,
a spring being provided, attached to the base plate, to give a return motion of
the said feed arm, and 1 thus obtain what I may call a rectangular feed, that is,
a feed which advances in a practically horizontal line, then lowers and returns
in a horizontal line, rising vertically ready for the motions to be repeated. In
order to regulate the amount of feed, I provide beneath the base plate a sliding
bar with a tapered end to coact with the arm of the feed rock shaft. By moving
this bar in one direction, the distance to which the feed levers will be returned by
the spring will be decreased, and by moving the bar in another direction the
distance of feed will be increased and a shorter or longer stitch thus produced.
Rack teeth or the like may be provided for moving the sliding bar, operated by
a knob having an index plate and pointer, whereby the bar may be set or
returned to a position which will give a known or desired length of stitch.
Pivotted to the underside of the base plate I provide an arm to carry a loop
spreading and holding device operated when in action by a cam on the looper
shaft and capable of being drawn out of action by means of a finger lever. Near
the end of the arm are two fingers, one fixed to the arm, the other pivoted thereto,
held by a spring in contact with the first finger. These fingers, hereinafter
termed the spreader, are opened at their extremities to allow the needle to pass

page_text: through same, and are capable of opening to allow the needle to pass when the
fingers are drawn away laterally.
Under the throat plate, which is formed with a needle aperture and slotted to
receive the bifurcated feed jaw as usual, I add a loop guard consisting of a piece
of wire extending transversely to the aperture in the throat plate to prevent the
loops of needle thread drifting away from the stitching devices.
Between the thread supply arm and the needle I provide an intermittently
acting auxiliary tension, so arranged as to press on the thread. and produce a
slight tension when the thread supply arm lowers as aforesaid. This may consist
of a piece of spring metal fixed to the machine head and opened or closed on the
thread by means of a cam-shaped recess cut in the reciprocating needle bar.
When forming a locked chain-stitch the shuttle spool case is in position contiguous
to the looper hook and the spreader is in action and governed by its cam to hold
and retain at proper times the loops of needle thread. To produce a lockstitch, it
is only necessary to throw the spreader out of action by means of its finger lever.
To produce a chain stitch, the shuttle spool case is to be removed and the spreader
is to be thrown into action.
Dated this 28th day of February 1893.
BREWER & SON,
London and Leeds, Agents for Applicant.
COMPLETE SPECIFICATION.
Improvements in Sewing Machines.
I, VICTOR WITTE, of 4 Newgate Street, in the City of London, Sewing
Machine Manufacturer, 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 refers to improvements in sewing machines, whereby one or other
of three varieties of stitches may be produced by the same machine, namely a
lock-stitch of the ordinary type, a chain stitch also of the ordinary type, and a
chain stitch with a second locking thread therein, or as
may call it a "locked-
chain-stitch," and my invention further refers to improvements in the mechanism of
the same machine, whereby I obtain a more direct feed, a regular stitch, and
moreover, stitches which may be increased or decreased in length according as may
be required with an index whereby the machine may be caused to produce or
reproduce any particular size of stitch, all as hereafter described and illustrated
with reference to the accompanying drawings as follows:
Figure 1 is a front sectional elevation of a sewing machine constructed according
to my invention.
Figure 2 is an inverted plan of the mechanism beneath the base-plate of the
machine.
Figure 3 is a left hand end elevation, the base plate being shewn in section.
Figure 4 is a similar view of the lower part of the machine to more particularly
illustrate portions of the feed device.
Figure is a longitudinal sectional elevation looking from the back part of the
machine to further illustrate the feed regulation devices under the base plate.
Fig. 6 is a plan of the feed index.
Figures 7 and 8 are respectively central vertical section and plan views of the
throat plate.
Fig. 9 is a perspective view of the feed levers.
Figure 10 is a perspective view of the auxiliary thread tension.
Figure 11 is a perspective view of a portion of a loop spreading device.
Figure 12 is a vertical section shewing the looper with the shuttle spool in position
on a larger scale than Figs. 1 and 2.

page_text: Figure 13 is a sectional end view, and Figure 14 an inverted plan view shewing
a modified arrangement of loop spreading and holding device.
Figures A, B, C, D are diagrams illustrating the operation of the stitch
mechanism. Fig. E illustrates the lock-chain-stitch as it appears upon the under
part of the material, and Fig. F-shews the same stitch upon the upper part of the
material.
Similar letters of reference indicate like parts in the several figures.
A is the base plate of the machine. B is the arm carrying the head framing C ;
D is the main driving shaft, E is the needle bar receiving reciprocative motion
from the main shaft D at proper times, F is an ordinary thread tension, and G is a
thread supply arm for drawing thread from the needle spool for the needle supply.
His the presser foot, raised or lowered by finger lever H. J, Figs. 1 and 2, is
the lever for communicating rotary motion from the main shaft D to the looper
shaft J. I have not in these drawings considered it necessary to illustrate
particularly the modes of communicating motion from the main driving shaft to
the needle bar E, the thread supply arm G and looper shaft J', as such mechanism
is well known to those skilled in the art, and does not form any part of my
invention.
In
The needle thread passes from the spool B' over a thread guide F¹ between the
tension plates F, down to the thread guide F up through the eye of the thread
supply arm G, through an auxiliary tension device G₁ hereafter described, and.
through the needle eye. Upon the end of the looper shaft J¹ below the needle is
mounted the looper J', having a hook J' and recessed centrally to receive a
case J, Fig. 12, containing the shuttle spool carrying the under_thread.
machines according to my invention, this spool case J' may be removed or replaced
when desired, it being retained within the looper by a ring K, carried by arm K'
on shatt K sliding in bearings K' on the under side of the base plate A. The
shaft K is retained in position by a spring K, Fig. 2.
When it is desired to
remove or replace the shuttle spool case, the knob K is seized, by the operator
and pulled, the spring compressed, and the shaft K* partially rotated, bringing the
ring K into the position shewn at Fig. 3, when the spool case J* may be removed
or placed in position as required; K is a pin fixed onto the arm K' of the
ring K, and this pin K takes into an aperture in the extension of the fixed
bearing K when the ring is placed as in Figs. 1 and 2, and thereby assures
accuracy of position. The shuttle-spool-case J has a fixed tongue Jx which
takes into the recess K* (Fig. 2) of the ring when the latter is closed upon it,
whereby the said shuttle spool case is prevented from being rotated.
Upon the looper shaft J¹ I provide two cams J' J' adjacent to one another (see
Figs. 2 and 4) to act upon an arm L upon which the feed jaw L' is fixed. The
feed arm L, shewn detached and in perspective at Fig. 9, is pivotted at its rear
end between two arms L² of a rock shaft L' carried in centre bearings from lugs
on the under side of the base plate; the cam J' acts within the fork of the feed
arm L to give the rising and falling motion thereto, and the cam J* acts against
the projection L to give the advance feed motion, while a spring L' attached to
base plate acts at the back of the feed arm L to give the return motion to the
feed arm.
By these means I obtain what I may call a rectangular feed, that is,
the feed jaw while advancing the work travels forward in a practically horizontal
line, then lowers, returns in a horizontal line (by the action of spring L) and rises
vertically ready for the motions to be repeated, a greater regularity and a more even
stitch being thereby obtained.
In order to regulate and govern the amount of feed, and consequently the length
of stitch, I provide in guides, beneath the base plate, Figs. 2 and 5, a sliding bar M
with a sloped or tapered end, arranged to co-act with a part Le on the arm of the
rocking shaft L. By advancing the bar M towards the left hand in Fig. 2, the
distance which the feed levers will be returned by the spring L will be limited,
and consequently a shorter stitch will be produced, that is, by moving the bar to

page_text: the right hand (Fig. 2) a longer stitch is produced, while a movement of the bar M
to the left hand shortens the stitch. Motion is communicated to the bar through
the rack teeth thereon, gearing with a pinion M', Figs. 2 and 5, operated by a
knob M on the base plate; the base of the knob M is formed with a divided
disc, see Fig. 6, and contiguous thereto is a fixed pointer M³, whereby the knob,
and consequently the bar M, may be at any time set or returned to a position which
will give a known or desired length of stitch.
When the machine is to form a chain stitch or a locked chain stitch an instrument
is provided to pass through and receive the loop cast off the rotating hook and to
retain and spread same while the needle passes therethrough, and then to cast off
the said loop around the needle thread. With this object and according to my
invention I provide an arm N, pivotted at N¹ to the underside of the base plate A,
Fig. 2, this arm N being pressed in the direction of the arrow, Fig. 2, by a
spring N. P is a finger lever pivotted to the base plate at P' and serving (when
in the position shewn in full lines Fig. 2) to retain the arm N out of action.
When the lever P is moved into the position shewn by dotted lines the arm N is
allowed to act and becomes a factor in the stitch mechanism; N³ is a bracket on
arm N, and when in action comes against a cam N7 located on the looper shaft J',
the rotation of the cam N' serving to give the arm N certain motions as mentioned
hereafter when describing the action of the stitch devices. Near the end of the
arm N are two fingers N* N*, N* being fixed to the arm N and N° pivotted thereto
and held by a spring N° Fig. 2, in contact with the finger N'. These fingers N'N',
hereinafter termed the "spreader," are opened at their extremities, see Fig. 11, to
allow of the passage of the needle through same, and the finger N° turns on
its pivot and allows the needle to pass when the said fingers and arm N are
caused to recede laterally, as hereinafter mentioned by the action of the cam N'.
Instead of the arm N moving in a horizontal plane, I may arrange same in a
vertical plane and dispense with the hinged finger N³ as is shewn at Figs. 13
and 14, where N is the arm mounted on a stud N¹ carried from the base plate by
an extension of the looper shaft bearing lug. The upper part of the arm N ís
formed with a pointed end as shewn, to enter the loop of thread for retaining and
spreading the loop; N' is a cam on the looper shaft J' acting on a roller N
on the arm N for withdrawing the, said arm N, the advance motion thereof being
effected by a suitable spring such as N³, one end thereof acting on the arm N and
the other end being fixed to the bearing lug. In order to give the arm a lateral
motion after its entry into the loop for spreading the latter, I provide a cam N** on
the back of the rotating hook J³ shewn in dotted lines Fig. 13, and at the proper
time this cam N× causes the arm N to be slidden on its stud N', the helical
spring N serving to return same to position shewn. A lever or catch device may
be employed to hold the arm N away from the cams and out of action when
producing a plain lock stitch.
The throat plate Figs. 7 and 8 is formed with the needle aperture and is slotted
to receive the bifurcated feed jaw, as is common in such sewing machines, but I
add beneath the throat plate and attached thereto what I may call a loop guard R
consisting of a piece of wire extending transversely to the aperture in the throat
plate, and serving to prevent the loops of needle thread drifting towards the left
hand of the stitch devices and out of the zone of their action.
The thread supply arm G is timed to rise from the full line position Fig. 1 to
the dotted position therein, at the commencement of the downward movement of
the needle, and draws thread from the needle spool, the supply arm G becoming
again partially lowered before the needle has finished its descent; now in sewing
machines constructed according to my invention, I provide an intermittently
acting aux liary tension between the ordinary thread supply arm G and the needle,
so arranged as to press on the thread and produce a slight tension when the arm G
lowers as aforesaid, and so to prevent the slack of the thread descending to about
the needle. This device is shewn at Figs. 1 and 3 and again in perspective on a

page_text: larger scale at Fig. 10, to which I will refer. T is a piece of spring metal fixed to
the machine head C at T', the thread passing from the eye of the supply arm G
over a fixed guide arm C' on the frame and then between a finger T of the part T
and the lower part of the machine head C. The lower part of the spring-piece T is
formed with a bearing piece T', and there is a recess E' of suitable length formed
in the needle bar E, so that when the recess E' comes opposite the bearing piece T³
the finger T' presses the thread between itself and the frame head C' and produces
the auxiliary tension upon the thread.
The machine is capable of producing as aforesaid one or other of three varieties
of stitch that is, an ordinary lock stitch, chain stitch, and a locked chain
stitch, and I consider it convenient to describe the formation of this latter
stitch first as it brings the various functions of the parts fully into operation.
The operation of the machine when it is desired to produce a locked chain stitch
such as is shewn at diagrams Figs. E and F hereinbefore referred to is as follows:
The piece of work is placed in position, the presser foot H lowered, the shuttle
spool in its case J is inserted into the hollow of the rotating hook disc J' and
retained therein by allowing the guard ring K to close upon same, while the
tongue of the shuttle spool case takes into the recess K* in the ring. The operating
lever P is placed into the dotted position shewn at Fig. 2, thereby allowing the
movements of the spreader arm to be controlled by its cam N³.
Upon the machine being operated, the needle descends through the material and
through the jaws of the spreader, as in diagram Fig. A and Fig. 11, and then sheds
its loop of needle thread, the thread controlling lever G descending from its upper
dotted position in Fig. 1, and thereby supplying thread during the said descent of
the needle. The loop of needle thread is caught by the rotating hook J* (in the
diagram Fig. A the hook is just about to catch a loop); as the hook rotates, and
just as it has caught the loop and the needle commences to rise, the spreader recedes
to the right hand, its jaws opening and passing away from the needle while the
latter completes its rise and the spreader N N again rapidly advances to the left
hand to the position shewn at diagram Fig. B, passing through the loop, while the
hook J carries the said loop of thread around the shuttle case as illustrated at
diagram Fig. B and delivers the loop upon the neck of the spreader, as at diagram
Fig. C, which spreader remains stationary for this purpose. Upon the needle again
descending through the material, the spreader resumes its position, diagram Fig. A,
and allows the needle to pass through its jaws. Now while the loop of needle
thread is being carried around the shuttle spool by the rotating hook, the feed
takes place, and this, together with the spreader moving slightly to the right hand
from diagram C to A, causes the first loop which is around the neck of the spreader
to be stretched out, so that on the second descent of the needle, the latter passes
through the stretched out loop, which latter (the loop) by the retrograde movement
of the spreader from position in diagram A to D is thrown off the spreader to
around the needle tbread, the second loop of needle thread is caught by the hook .1³
passed over the shuttle case and deposited upon.the neck of the spreader, and these
operations are repeated, whereby the locking thread contained in the shuttle spool
is deposited within the loops formed by the chain stitch and a stitch is produced as
is shewn at diagrams Figs. E and F.
In order that there shall always be a sufficient tension upon the needle thread
the spring auxiliary tension T acts as before described so that when the thread con-
trolling arm moves from the dotted to the full line position, Fig. 1, and draws a
quantity of slack thread from the needle spool, the recessed surface on the needle
bar comes opposite the bearing part T of the said auxiliary tension, and allows the
latter to grip the thread, with just sufficient tightness to prevent a quantity of slack
remaining between the said tension and the needle.
To produce the ordinary chain stitch, all that is necessary is to remove the
shuttle spool with its case J, which may be readily done by releasing it from its
guard ring K, as previously explained. When the chain stitch is being produced,
the spreader carrying lever N is left in action.

page_text: To produce the ordinary lock stitch the shuttle spool and case is placed in position
(Fig. 12) and the spreader arm N is thrown out of action by moving the finger
lever P into the position shewn by full lines at Fig. 2, and the lock stitch is then
produced as in ordinary lock stitch machines with a rotating hook and shuttle..
I am aware that attempts have been made to manufacture sewing machines to
produce, two or more stitches by a re-adjustment, removal or addition to their
operative mechanism, and I am also aware that shuttles have been before now
removed or thrown out of action to change a lock stitch to a chain or other stitch,
and. I therefore only lay claim to arrangements and combinations of improved
devices as hereinunder stated.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a sewing machine arranged to produce either a lock stitch, a chain stitch,
or a locked chain stitch, having a reciprocating needle bar E, a thread supply
arm G, a presser foot H, a looper shaft J¹, a rotary looper J J' mounted thereon
and a ring-shaped holder K for carrying the shuttle spool case J, ring arm K¹ on
shaft K, spring K and knob K for disengaging and replacing the said spool
case J from the ring K together with ordinary mechanism for actuating these
parts, the combination therewith of loop spreading and retaining fingers N N to
co-act with the looper hook and receive the loop therefrom when forming a chain
or locked chain stitch, an arm N pivotted to base plate to carry the fingers N₁ N',
operating cam N on looper shaft J¹ and return spring N³ for actuating the arm N,
a finger lever P pivotted to base plate at P¹ to throw the arm N out of action when
forming a lock stitch, and a feed jaw L", an arm L carrying the said feed jaw L',
rock shaft L' mounted in bearings on base plate, arms L³ on rock shaft L' between
which the arm L is pivotted, a cam J' on the looper shaft to give vertical motion,
and a cam J thereon to transmit lateral advance motion to the feed arm L, and, a
spring L to give return motion to the said arm L together with a tapered bar M,
to co-act with part L of arm L, and mechanism for sliding the bar M for
regulating the throw of the feed device and lengthening or shortening the stitch as
set forth.
2. The combination with a rotating looper shaft J1 carrying a looper hook and
disc J³ J³, a separate circular case J containing a shuttle spool and devices for
holding the spool case J' contiguous to the looper J' of a loop spreading and holding
device to co-act with the looper hook and receive the loop therefrom, consisting of
an arm N pivotted to the base plate, a finger N* fixed to the arm N, a finger N
pivotted to arm N and a spring No to hold finger N° adjacent to finger N, a
cam N on looper shaft and return spring N' for actuating arm N, together with a
finger lever P pivotted at P₁ to the base plate to throw the arm N and parts out
of action when required and an auxiliary intermittent spring tension T attached to
the bracket head of machine, a recessed part E' on the needle bar E to operate the
tension spring T and cause the needle thread to be gripped or released at proper
times as set forth.
3. The combination with the stitch devices as claimed in Claim 2 of feed
mechanism consisting of a feed jaw L¹, an arm L carrying the feed jaw L' rock
shaft L carried on bearings from base plate, arms L' on rock shaft L' between
which the arm L is pivotted, a cam J' on the looper shaft to give vertical reciprocative
motion to the feed arm L, a cam J' also on looper shaft to give lateral advance motion
to the feed arm Land a spring L' to give return motion to the said arm L together with
mechanism for regulating the throw of the feed device and lengthening or shortening
the produced stitch consisting of a bar M with tapered end, to co-act with fixed
bracket L on arm L2, bearings on base plate to carry sliding bar M, pinion M¹
taking into teeth on rack of sliding bar M, knob M* to operate pinion M and slide
bar M, index dial on knob M' and fixed pointer on base plate whereby any
desired particular length of stitch may be produced or reproduced as set forth.

page_text: 4. In a sewing machine arranged to produce either a lock stitch, a chain stitch
or a locked chain stitch, having a reciprocating needle bar E, a thread supply
arm G, & presser foot H, a looper shaft J and a rotary looper J J³ mounted
thereon, and a removable spool case J' retained in position when desired by a spring
holder K together with mechanism for actuating these parts, the combination
therewith of a loop spreading and retaining arm N operated in a vertical plane by
suitable cams and springs and capable of being thrown out of action when desired,
all substantially as described with special reference to Figs. 13 and 14 of the
accompanying drawings.
Dated this 21st day of August 1893
BREWER & SON,
London and Leeds, Agents for Applicant.
BREWER & SON,
London and Leeds, Agents for Applicant.