Improvements in Sewing Machines.
Year: 1891

page_text: Date of Application, 2nd Dec., 1891-Accepted, 2nd Jan., 1892
COMPLETE SPECIFICATION,
[Communicated from abroad by THE SINGER MANUFACTURING COMPANY, of
New York, United States of America, Sewing Machine Manufacturers.]
Improvements in Sewing Machines.
I, ALEXANDER ANDERSON Manager of the Singer Manufacturing Company's
Works, Kilbowie, Dumbartonshire, do hereby declare the nature of this invention
and in what manner the same is to be performed, as communicated to me, to be
particularly described and ascertained in and by the following statement :-
My invention which relates to sewing machines comprises improvements in the
treadle mechanism, in the shuttle and shuttle mechanism and adjuncts and in the
needle clamp and guide of such machines.
The first part of my invention has for its object to provide an improved treadle
mechanism for sewing machines by which the operator is enabled to drive a machine
at high speed with a minimum expenditure of power. To this end I provide a stand
with a cross brace of suitable construction to afford bearings for the driving shaft
and for a rotary pedal shaft, which latter is provided with two cranks arranged
at 180° apart and provided with suitable pedals. The pedal shaft and the driving
wheel shaft are each provided with two cranks preferably arranged 90° apart and
connected by suitable pitmen. The pedal shaft being provided with twin cranks
and pedals affords an easier driving movement than the rocking or vibrating pedals
heretofore generally in use, while the twin quartering cranks through which and the
pitmen the movements of the pedal shaft are transmitted to the driving wheel shaft.
avoid any difficulties which might otherwise arise from dead centres.
In Sheet 1 of the accompanying drawings,
Fig. 1 is a perspective view of a sewing machine stand embodying this part of my
invention.
Fig. 2 is a front side view of the same.
Figs. 3 and 4 are detailed views to illustrate the arrangements of the cranks on
the driving and pedal shafts.
A denotes the side frames of a sewing machine stand supporting the table B on
which is mounted the sewing machine C. The side frames A. are connected by the
brace D consisting of the outer uprights d and d', the intermediate upright d² and
the upper and lower cross bars d³ and the said brace being connected to the side
frames by suitable bolts a.
E denotes the driving fly wheel carried by the shaft e preferably formed with
conical ends journalled in the cross bar ³ and an adjustable socket screw f
attached to the upright d the said shaft e being provided with quartering twin
cranks, one of which is preferably at right angles to or 90° from the other.
Journaled in the lower portions of the uprights and is a pedal shaft G
provided with oppositely arranged twin cranks carrying suitable pedals h, the
said shaft having at its right hand end, outside of the upright the quartering
cranks connected by pitmen with the quartering cranks e of the driving
shaft e.
It will be obvious that the pedal shaft with its twin cranks and pedals may
be rapidly rotated with an easy movement and that the power applied thereto
will be positively transmitted to the driving shaft through the quartering twin
cranks on the pedal and driving shaft and their connecting pitmen.
The object of the second part of my invention, which is an improvement on
that described in the Specification of Letters Patent No. 15663 of 1887, is to
improve the shuttle and the means for controlling the shuttle-thread in the
formation of the stitch.

page_text: In my invention the shuttle which passes through the loop of the needle
thread has been provided with a take-up which is directly connected to the
shuttle, and which in its movements acts upon the shuttle thread extending from
the tension device of the bobbin case to the underside of the work, the said
take-up acting upon the shuttle thread as the shuttle is moving backward and
while the needle is about at its highest point and the take-up for the needle
thread is finishing the stitch, the feed also at such time being up and making
its forward movement.
The take-up co-operates with a bridge secured to the shuttle race or to some
suitable fixed part of the frame, and the edge of the take-up and of the bridge
are, as shewn, of such shape as to bend or crimp the shuttle-thread between
them when the slack in the said thread is to be taken up in finishing the stitch,
bending the shuttle-thread as described increasing the extent to which the shuttle-
thread may be drawn.
The bobbin case has been provided with a tension device located thereon at
the centre of rotation of the bobbin, and as herein shewn the tension adjusting
screw is extended into the end of the post or stand erected on the shuttle to
hold the bobbin-case.
The driver for moving the shuttle in its race has been improved by providing
it with a thread guard which is extended backwardly in a direction opposite to
the point of the shuttle, the said thread guard being interposed betweeen the
shuttle thread and the point of the shuttle as the latter arrives in position to
enter the loop of needle-thread, the end of said thread guard being bent inwardly
or made cam-shape to act against and deflect out wardly the shuttle thread should its
slack portion be across the needle hole at the underside of the usual throat plate
when the shuttle is moved fully back.
Fig. 1 on Sheet 2 of the drawings represents a sufficient portion of a sewing machine
to enable my invention to be understood, the said lig. shewing the thread plate
removed, the feed bar broken off, and the overhanging arm and head broken away
all except the needle-bar, the tension mechanism for the shuttle being also partially
broken out to better shew the construction thereof.
Fig. 2 in front elevation shows the shuttle race and the driver and shuttle.
Fig. 3 is a vertical section on the line - Fig. 1, on a larger scale, the said
fig. by dotted lines shewing the shuttle thread behind the bridge which co-operates
with the take-up carried by the shuttle.
Fig. 4 shews the shuttle and bobbin case within it, the dotted lines shewing the
shuttle thread.
Fig. 5 a top view of the parts shewn in Fig. 4.
Fig. 6 shews the shuttle driver detached.
Fig. 7 shews in detail the spring and two plates constituting the tension mechanism
for the shuttle thread.
Fig. 8 shews the feed-bar detached.
Fig. 9 on a smaller scale shews the front of the head of the machine broken off
from Figure 1.
Fig. 10 shews the shuttle in edge view.
Fig. 11 is a view of the take-up device of the shuttle removed.
Fig. 12 is a perspective view of the bobbin case and
Fig. 13 is a perspective view of the shuttle.
The bed plate A, the head, see Fig. 9, of the overhanging arm B, the take-up T
for the needle thread, the presser bar P, the needle bar, its attached needle, the
shaft D carrying at its front end the shuttle driver H and the feed bar K shewn
partially in Fig. 1 and fully in Fig. 8, the shuttle S having the arm, the beak ',
the loop discharger 13, the stud 15, the bobbin m for the under thread, and the
bobbin case are all substantially as described in the Specification of the Patent
before referred to, where the like parts are shewn by like letters, except that the
driver has at its end next the beak of the shuttle a thread guard and that the
face of the bobbin case has been somewhat changed in shape, as will be hereinafter

page_text: described; and in practice the said parts will all be operated as described in the
said Specification.
The shuttle-race herein shewn is composed of plate a represented detached in
Fig. 2.
This race is grooved at its rear side, as shewn, by the section Fig. 3 and is
attached to lugs at the underside of the bed plate by screws as a³.
The rear side of the shuttle race plate at or about its lower edge has secured to
it preferably as in the Specification of Letters Patent No. 5062 of 1882 a yielding
back plate but instead of this particular back plate 1 may employ any other
back plate.
The shuttle race, at its upper end just below the usual throat plate, not herein
shewn, has secured to or formed as part of it a bridge d, the attachment as shewn,
being by screws d' see Fig. 1.
The bridge d shewn in section in Fig. 3 is grooved longitudinally for the passage
through it of the take up e shewn as a separate plate attached by screws e or in
other suitable manner directly to and moving with the shuttle S through the loop
the said take-up acting against the shuttle thread extended from the tension device
of the bobbin case to the work, as the shuttle is returning to its starting point, the
take up at such time bending or corrugating rather sharply the shuttle thread
between it and the two lips at the sides of the groove in the bridge, as shewn by
dotted lines Fig. 3.
At the time that the take-up e acts on the shuttle thread the stitch is being
finished or set, and at such time the needle-bar will be at the upper end of its stroke,
and the take-up T for the needle thread will be in about its highest position and
the feed bar K will be elevated on its forward journey.
This take-up e also, it will be understood, will meet the shuttle-thread as the
shuttle is being passed through the loop of needle thread, but at such time the
feed bar will be down, and, in the lowest position of the feed, the shuttle thread
between the bobbin case and material will be slack.
The shuttle is started forward when the feed bar is down, as stated, and the
shuttle thread slack, and to prevent the slack of the shuttle thread getting across
the path of the needle or in the path of the point of the shuttle I have provided the
driver H, attached to the oscillating shaft D, common in the Specification of Letters
Patent No. 15663 of 1887 with a rearwardly extended thread guard h, the outer
end of which is bent inwardly as h'.
This thrend guard as the shuttle passes into its backward position ready to be
again moved forward to enter a loop of needle thread, passes between the shuttle
thread and the path of the needle, and pushes the shuttle-thread outwardly so
that the said thread cannot possibly return again quickly enough to get into the
path either of the beak or point of the shuttle $ or of the descending needle
before the point of the shuttle enters the loop of the needle thread.
The bridge referred to besides co-operating with the take-up e, as described, also
co-operates with the projection 2 from the bobbin-case to prevent the rotation of the
said case, the said projection entering a slot 3 cut, as shewn, in the lower edge of
the said bridge.
The bobbin case, see Figs. 1, 4 and 5, has a bulged face 4 which nearly covers
the bobbin the said bulged face having projections or high points, as 5 and 6, to aid
in spreading the loop of needle thread while it is yet held by the beak or point of
the shuttle, the said projections spreading the loop of needle thread sufficiently to
readily pass and not catch upon the tension device, to be described used with the
bobbin case.
The face of the bobbin case is cut away or chambered centrally, see Fig. 3, to
leave a hub 8, which receives about it the movable member or disc 10 of the tension
device, see Figs. 3 and 7, the said hub being screw threaded to receive in it the
tension regulating screw 12, which, before it is passed through the said disc and
into the said hub, is passed through the cover 13 and through the spiral or other
spring 14 held in the space between the said disc and cover, the said screw being

page_text: preferably split longitudinally so as to retain its position and serving, when turned
in one or other direction, to increase or diminish the effective pressure of the said
spring on the disc 10 and consequently correspondingly effect an increase or
diminution of the tension on the shuttle thread.
The cover 13 is provided with a finger 16, which, when the cover is in place,
enters a space in the bulged face of the bobbin case behind the projection 2, the
said projection thus aiding in keeping the shuttle thread in place.
The bobbin m surrounds a hollow stud y extended inwardly from the centre of
the bobbin case, the said stud in turn surrounding the usual post of the shuttle.
The bobbin case has a slot, as 17, through which to readily lead the shuttle
thread on its way from the bobbin to the tension device, already described, and in
addition thereto I have provided the said case at its upper side with a hole, as 18,
see Figs. 5 and 3, in line with the path of the needle, said hole enabling me to use
a bobbin case, and consequently a bobbin of greater diameter than were the said
hole omitted, for in the descent of the needle its point may enter the said hole.
The shuttle race plate has pivotted upon it, by a screw 20, the bobbin-case
retainer 21, which is herein shewn as an elbow lever struck from sheet metal, the
short arm of the said lever having a concavo-convex surface, or made like a spoon-
bowl, the convexed surface bearing against the bulged face of the bobbin-case to
keep it in the shuttle.
The outer end of this lever has a stud 22, which enters a suitable hole, as 23, in
the race plate, to thus retain the lever in working position.
The bridge d herein described and the take up e on the shuttle S may be
employed to advantage in connection with machines shewn in the Specification of
Letters Patent No. 15664 of 1887 wherein the shuttle is moved by or in the carrier,
so I do not desire to limit this invention to the particular means for supporting the
shuttle during its oscillation as the said means may be either the race plate or
a carrier as shewn in the last-mentioned Patent.
The third part of my invention has for its object to provide an improved needle
clamp and thread guide for sewing machine needle bars of such construction that
different sized needles may be securely held in place by the clamp, and the clamp
be retained on the needle bar by the thread guide so that the said clamp cannot
slip off from the said bar when the needle is loosened. To this end I attach to the
lower end of the needle bar a thread guide having an eye through which the needle
loosely passes, and which is slotted so as to be easily threaded, said thread guide
extending beneath the needle clamping collar in such a manner as to prevent the
said collar from coming off the needle bar when the set screw is loosened and the
needle clamp or clamping collar is provided with a V-shaped groove to co-operate
with the needle-receiving groove formed in the needle bar, all as will hereinafter be
more fully described.
In Sheet 3 of the accompanying drawings
Fig. 1 shews a portion of a needle bar with my improvement applied thereto
and with the needle in position.
Fig. 2 is a vertical section of the same.
Figs. 3 and 4 are horizontal sections on line -, Fig. 1, shewing different sized
needles in the clamp and
Fig. 5 is a detail perspective view of the thread guide and its shank.
A denotes a needle bar partly cut away at its lower end and provided on one
face with a concave groove a for the reception of the shank of the needle a'. The
needle is secured to the needle bar by a clamp or clamping collar B held in place
by the set screw the said clamp or clamping collar having in its inner face a
vertical V-shaped groove which is opposite the groove a in the needle bar. C is
the thread guide, the shank of which is attached to the needle bar by the set
screw c, the said thread guide being bent nearly at a right angle to its shank so as
to extend beneath the needle clamp and the lower end of the said needle bar, the
said bent portion being provided with an eye d loosely surrounding the needle and
preferably open or slotted as shewn, so that the thread may be readily drawn into

page_text: the same.
The thread guide extending thus beneath the needle clamp serves to
prevent the latter from slipping off from said bar when the set screw is loosened
for the purpose of removing the needle, and the inconvenience heretofore frequently
arising with needle clamps similar to that herein shewn will thus be avoided.
The V-shaped groove in the needle clamp, co-operating with the rounded or
concave groove a in the needle bar enables needles having different sized shanks to
be properly centred and to be securely held in place, as will be readily understood
by reference to Figs. 3 and 4.
The shank of the thread guide C is preferably provided with a hole c¹ opposite
the clamp-holding set-screw and into and through which the inner end of the
said set screw extends to impinge against the needle bar; and when thus con-
structed the engagement of the said inner end of the said screw with the shank of
the thread guide will prevent the needle clamp from dropping when said set screw
is but slightly loosened; but should the said set screw be accidentally turned out
far enough to disengage its inner end from the said. hole the thread guide,
extending beneath the said clamp, will prevent the latter from dropping off” from
the needle bar, as hereinbefore described.
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, I declare that what I claim is :-
1. A sewing machine stand consisting of side frames and a brace connecting
the same, the said brace being composed of upper and lower cross bars, two outer
uprights and an intermediate upright, combined with a driving crank shaft and a
rotating cranked pedal shaft, both of which are suitably journalled in said brace,
and a suitable connection between said shafts, substantially as described with
reference to Sheet 1 of the drawings.
2. A treadle mechanism for sewing machines consisting of the combination with
a sewing machine stand, of a rotating pedal shaft provided with twin driving
cranks and pedals and with twin transmitting cranks, and a driving shaft also
provided with twin cranks, and twin pitamen connecting the transmitting cranks of
the pedal shaft with the cranks of the driving shaft, substantially as described
with reference to Sheet 1 of the drawings.
3. A. sewing machine treadle mechanism consisting of the combination with a
sewing machine stand, of a rotating pedal shaft mounted in the lower part
thereof and provided with oppositely arranged twin driving cranks and pedals
and with quartering transmitting cranks, a driving shaft mounted in said stand
above the pedal shaft and also provided with quartering twin cranks, and pitmen
connecting the said quartering cranks of the pedal and driving shaft, substantially
as described with reference to Sheet of the drawings.
4. The combination with the side frames A, of the brace D consisting of the
outer uprights and d' the intermediate upright d² and the cross bars d³ and dª,
the driving shaft carrying the driving fly wheel E and provided with twin
quartering cranks e, the rotating pedal shaft G journalled in the uprights¸d'
and d and provided with oppositely arranged twin driving cranks carrying
the pedals h, said shaft also having twin quartering transmitting cranks gland
the twin pitmen connecting the said transmitting cranks with the said
cranks of the driving shaft e substantially as described with reference to
Sheet 1 of the drawings.
5. The needle bar, its attached eye pointed needle, the usual vibrating take-up
lever for the needle thread, the shuttle race, the bridge d and the bobbin and
bobbin case, combined with the shuttle and the fixed and rigid take-up attached
directly to it, the said take-up passing with the shuttle through the loop of the
needle thread and acting upon the shuttle thread, thus aiding in setting the stitch,
substantially as described with reference to Sheet 2 of the drawings.
6. In a shuttle sewing machine, the shuttle driver H having the rearwardly
extended thread guard, the outer end of which is bent inwardly, as at h³,

page_text: substantially as shewn and described, to prevent the slack of the shuttle thread
getting across the path of the needle or in the path of the point of the needle,
combined with the shuttle, its bobbin, the needle and usual operating mechanism,
substantially as set forth with reference to Sheet 2 of the drawings.
7. In a sewing machine, the shuttle race and the bridge d, extending entirely
across the upper portion of said race and fixed upon opposite sides of the said
shuttle race, and having the notch 3 in its lower edge and a longitudinal groove for
the passage of the take-up e combined with the shuttle provided with the said
take-up, the bobbin case and its arm 2 extending into the notch in said bridge, and
a support for the bobbin-case, substantially as described with reference to Sheet 2
of the drawings.
8. The shuttle race plate having a hole 23 and the lever 21 pivoted to the
said plate and having a stud 22 in one arm to engage the hole in said plate,
and having its other arm made spoon-bowl shape, combined with a bobbin case
having a bulged face against which the bowl shaped arm of the lever bears, and
against which it is held by the engagement of the stud and hole before mentioned,
substantially as shown and described with reference to Sheet 2 of the drawings.
9. In a sewing machine, the combination with the shuttle race provided with the
bridge extending entirely across the upper part thereof and provided on its
inner face with a groove, of the shuttle provided with a take-up which, in
operation, extends into said groove, to operate substantially as set forth with
reference to Sheet 2 of the drawings.
10. The combination with the needle bar partly cut away at its lower end and
provided with a needle receiving groove or recess, of a needle clamp, a set screw
for tightening the same and a thread guide attached to the said needle bar and
extending beneath the said clamp and the lower end of the needle bar and having
an eye through which the needle loosely passes, substantially as described with
reference to Sheet 3 of the drawings.
11. The combination with the needle bar A partly cut away at its lower end and
provided with a needle receiving groove or recess, of a needle clamp B having a
set screw a thread guide C provided with an eye through which the needle passes
loosely, the said thread guide being bent nearly at right angles to its shank so as
to extend beneath the said thread clamp and the lower end of the needle bar, and
the set screw e passing through the shank of the said thread guide and serving to
secure the latter to the needle bar, substantially as described with reference to
Sheet 3 of the drawings.
12. The combination with a needle-bar partly cut away at its lower end and
provided with a rounded or concaved groove to receive the shank of the needle, of a
needle clamp having in its inner face a V-shaped groove opposite the said concave
groove and co-operating therewith to securely hold different sized needles, and a
set screw for attaching said needle-clamp to said needle bar, substantially as
described with reference to Sheet 3 of the drawings.
13. The combination with the needle bar A, of the needle clamp B having the
set screw b, and the thread guide C attached to said needle-bar and provided with
the hole opposite said set screw, substantially as described with reference to
Sheet 3 of the drawings.
Dated this First day of December 1891.
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow, Agents.