IMPROVEMENTS IN SEWING MACHINES
Year: 1878

page_text: LETTERS PATENT to Alexander Melville Clark, of Chaucery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS IN
SEWING MACHINES." A communication from abroad by The Wilson Sewing
Machine Company (Incorporated), of Chicago, in the County of Cook, State of
Illinois. United States of America.
Sealed the 10th January 1879, and dated the 5th November 1878.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 5th November 1878.
"
ALEXANDER MELVILLE CLARK, of Chancery Lane, in the County of Middlesex,
Patent Agent.
IMPROVEMENTS IN SEWING MACHINES." [A communication from
abroad by The Wilson Sewing Machine Company (Incorporated), of Chicago, in.
the County of Cook, State of Illinois, United States of America.]
This Invention relates to improvements in oscillating shuttle lock stitch sewing
machines. The standard and arm composing the frame of the machine are cast
hollow and in one with the bed plate. The main shaft passes through the arm and
operates the needle by a crank pin working in a grooved cross head attached to the
needle bar of such form that a certain timing may be given to the needle, as here-
after described.
Just behind the crank upon the main shaft is a cam for operating the take up.
Within the same casing as the needle bar is the presser foot bar. Projecting from
the presser bar is a bearing plate which comes out through the casing and sets
against an adjustable guide to prevent or to take up any lateral play the bar may
have. Below the bed are two parallel counter shafts, both actuated from the main
shaft, and having the one a rotary motion for operating the feed, and the other an
alternate rotary motion for operating the shuttle. Upon the rotary shaft is a taper
cam capable of sliding but prevented from turning on the shaft, which cam acts
. against an arın on the feed bar to move it forward. The cam is held or moved by

page_text: a forked arm fixed to a bar provided with an adjusting screw. Above the shaft
-lies-the-feed-bar-which-is-slotted-at-one-end, and has a pivot passing through the
slot. At the other end it rests upon a second cam on the end of the shaft which
strikes against the bar and-raises-it, the-first cam striking against a roller on an
arm-on-the feed bar to move it-forward, as above mentioned. When released from
the action of these cams a spiral spring brings the bar down and back.
This feed bar in the present case is made in two parts, but it may consist of a
single split bar. When made in two parts they are connected by a screw, and a
set screw passes through the one and bears against the other, so that they may be
sprung-asunder-more or less to raise the feed_claw carried by the upper part more
or less above the cloth plate. This rotary shaft and the rock shaft for operating
the shuttle are both actuated from the main shaft as follows:-
Upon the main shaft within the head of the hollow standard is a cam or eccentric
surrounded by a strap on the end of a rod, whose other end is attached to a crank
on the rotary or feed shaft.
About midway of the length of this eccentric rod is a pin which passes entirely
through, and is furnished at the back with a roller which plays in a vertical spindle
on the frame of the machine. To this same pin at the other side is connected a
short connecting rod whose lower end is attached to a crank on the rock shaft.
This mechanism gives the desired motions to the two shafts. The amount of
oscillation in the rock shaft may be varied by varying the throw of the crank, the
length of the connecting rod, or the position of its upper attachment.
The eccentric is fixed to the main shaft by one of two set screws fitting into
indentations made in the shaft slightly nearer together or farther apart than the
points of the screws, so that by loosening one screw and tightening the other the
eccentric may be turned slightly on the shaft so as to change the timing of the
take up needle and shuttle to enable either a tight or elastic stitch to be made.
The shuttle in this machine is caused to move in a curved line through the least
possible distance, only moving just far enough to clear the loop of the upper thread,
in other words, only a little farther than twice the length of the shuttle.
"
The
The shuttle operating rock shaft passes through a stationary plate which is
attached to the bed plate, and serves as the guide or "race" for the shuttle.
shuttle carrier, which is fixed to the end of the rock shaft, consists of a plate with
two horses at the extremities and a centre bearing between which the shuttle lies
close to the shaft hub, so that the motion will not only be as short as possible, but
will also be close to the centre, avoiding the shock incident to a long stroke. The
needle comes down a little behind the centre of the shaft.
The shuttle is constructed so that the bobbin may be of the largest possible
diameter. It has two connected cylindrical chambers whose axes, when the shuttle
is in position in the machine, are parallel with the oscillating shuttle driving shaft.
The larger chamber receives the bobbin, and the smaller one contains the tension
device. In the larger chamber is a stud on which the bobbin is placed, said stud
having a slot in one side through its entire length, which contains a spring for
retaining the bobbin in position.
The tension device consists of a screwthreaded stud in the smaller chamber in
the shuttle, and an internally threaded sleeve having a slotted head placed thereon,
and two centrally apertured discs placed on the said sleeve and pressed together
and outward against the head of the sleeve by a spiral spring on the stud and
sleeve.
The heel of the shuttle is cut away, so that when the shuttle is in place in the
machine the line of the heel is approximately radial to the centre of oscillation of
the shuttle carrier. The thread from the bobbin is let out under the head of the
sleeve and between the discs, and the spring below the discs creates a metallic
friction upon the thread between the discs and acts as a tension which is adjustablo
by tightening the sleeve. From the discs the thread is led out through a hole in
the shell of the shuttle and passes beneath a guard; or instead of being led from
the discs directly out to the guard the thread may be led back through the same

page_text: hole into the bobbin space, and thence out through a delivery hole in the shell of
the shuttle to the guard. This latter method ensures the thread from slipping out
from between the discs and loosening its tension.
To guard against the shuttle being thrown out of place I provide the race with a
circular or peripheral ledge.
This whole shuttle race consisting of the plate and ledge is made separate from
the bed plate in order that it may be more conveniently made, and is screwed to
the bed plate. The upper part of the ledge is removed to permit the thread to
draw from either direction without coming into contact with anything between the
shuttle and throat plate. To hold the shuttle from falling out sidewise under
motion I provide a hinged cover which is secured to the race in an opening covered
by a slide by a hinge pin which is surrounded by a spiral spring that serves both
to open the cover and to hold it closed by means of a catch. This cover is furnished
with a spring which bears against the shuttle when the latter is at the back end of
its stroke in order to cause it to lic close against the face of the race while the
shuttle point is entering the thread loop.
The take up device consists of a jointed arm pivoted at its upper extremity to
the end of the hollow arm of the machine frame, and provided with a bearing
roller just below the point against which the cam on the main shaft bears. The
joint of the take up conceals a spring which acts upon the lower portion of the
arm with a tendency to throw it back, and stops are provided to limit the motion
or yield of this arm, causing it at this limit in either direction to become rigidly a
part of the upper portion of the arm. At this joint a regulating disc is applied, to
which one end of the concealed spring is secured, the other end of the spring being
attached to the lower portion of the arm. The disc is turned and set by a small
screw to regulate the tension of the spring. A long loop having at one end a
leather pad stands in the path of the take.up arm and serves as a stop to said arm
to cause the lower part of the arm to unfold its full extent to determine the amount
of stroke of the take up. The take up strikes against the pad in its path in case
the tension is too weak to cause the thread to force the lower arm against its stop.
The needle thread passes from an eye at the upper part of the needle bar casing
under a pair of studs at the lower part of the said casing through an eye in the
lower extremity of the take up, and thence back over the other stud through a
guide on the lower end of the needle bar to the eye of the needle,
The tension device for the upper thread consists of a pair of plain or corrugated
plates in combination with a peculiar contrivance acting as a check on the thread
between said plates or wheel and the spool. This check consists of a hollow tube
within which lies a bar pivoted at the rear end. The upper part of the tube is
slotted with an T shaped slot. The stem of the T comes out to the mouth of the
tube, while the arms of the T are cut down at each side about half way across the
tube.
The thread from the spool passes into the tube through one arm of the T slot
under the bar and out at the other arm, thence round between the corrugated
plates or revolving tension wheel and through an eye, from whence it is led to the
needle.
The weight of the bar resting upon the thread affords the necessary check
between the plates or wheel and the spool to cause the thread to be gripped
sufficiently by the plates or wheel to cause the wheel to turn when tension is
applied to the same by a nut or screw. But in order to increase the pressure of
the bar beyond its weight, and to afford a means of adjusting the pressure a spring
is applied to the said bar in a slot in the same, said spring extending back of the
point at which the bar is pivoted to the tube, and a set screw bearing against the
spring, whereby its tension may be adjusted in order that it shall press the bar
down upon the thread with more or less force.
The operation and timing of the needle, the shuttle, and the take-up are as
follows:-
The needle being down through the cloth and just starting to rise a loop of

page_text: thread is, by the difference in friction of the cloth upon the needle and the thread,
thrown out below the cloth..
At this juncture the shuttle commences to move forward towards the loop, the
needle-thread-being-slack-and-the take-up-hanging vertically uninfluenced by its
-cam.-
When the shuttle is in-the-act of passing through the loop and the needle is still
rising, but has not yet reached its highest point, the lower arm of the take-up
yields to the limit of its stop, this yield being caused by and provided to accommo-
date the enlargement of the loop caused by the passage into it of the shuttle.
When the shuttle is at its lowest point and standing still, having drawn its
thread and set the stitch previous to its backward motion, the needle is also at its
highest point, and just starting down again the take-up is in the act of being
thrown over by its cam, and has drawn the thread of the loop up through the cloth
and through the eye of the needle tightening the upper thread of the stitch. Thus
in setting the stitch the eye of the needle is relieved of all strain of the thread,
which simply draws through the eye while the needle is above the cloth.
The motion of the needle bar imparted to it by the peculiar shape of the groove
in the cross bead heretofore alluded to is as follows:-The needle descends with a
nearly uniform speed and commences to ascend without pause, but slackens its
speed for a little way on its upward course, then regains its former speed, the object
being to gain time for the shuttle to pass through.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alexander Melville Clark in the Great Seal Patent Office on the
3rd May 1879.
ALEXANDER MELVILLE CLARK, of Chancery Lane, in the County of Middlesex,
Patent Agent.
IMPROVEMENTS IN SEWING MACHINES." A communication from
abroad by The Wilson Sewing Machine Company (Incorporated), of Chicago, in
the County of Cook, State of Illinois, United States of America.
This Invention relates to improvements in oscillating shuttle lock stitch machines,
and in order that the improvements may be more readily understood I have illus-
trated them in the accompanying Drawings, and will proceed to describe them with
reference thereto and to the letters and figures marked thereon.
Figure 1 is a front clevation of the improved machine; Figure 2 is a vertical
section taken through the casing in front of the needle bar and presser bar, showing
those parts and also the shuttle and its carrier below the bed plate; Figure 3 is a
similar section taken through the upright standard, showing the mechanism for
communicating motion from the main shaft to the two countershafts below the
bed plate; Figure 4 is an under side view of the machine; Figures 5, 6, and 7, are
skeleton views or diagrams illustrating the movement and timing of the needle
shuttle and take up.
Figure 8 is an enlarged view in section of the joint of the take up; Figure 9 is
a sectional plan of the stop for unfolding the take up lower arm to determine the
length of its stroke; Figures 10, 11, 12, 13, 14, are various views of the shuttlo
detached from the machine, the last Figure (14) being a section across the same at
the axis of the bobbin.
Figure 15 is an enlarged view of the tension device for the needle thread, shown
detached from the machine; Figure 16 is a top view of the same; Figures 17, 18,
and 19, are sectional views of part of the same; Figures 20, 21, and 21ª, are
sectional elevations of the feed apparatus; Figure 22 is a horizontal section of the
shuttle race showing the shuttle guard; Figure 23 is a vertical section of the hinged
shuttle guard and catch. Similar letters of reference indicate the same parts in all
the Figures.
front.
A is the cast iron bed plate of a form combining the desired strength with as
little weight as possible; A' is a hollow upright or standard at the right hand of
said plate, and A2 is a horizontal hollow arm extending therefrom and supporting
the head or casing A³. All of these parts excepting a part of the casing A³ and a
removable side to the standard (at the rear and not shown) are cast in a single
piece B is the main shaft mounted within the arm A, and extending out at
the right hand where it carries a band pulley B¹ and a balance wheel B²
This arrangement is preferred because the balance wheel is within easy reach
of the operator to start the machine by a pull of the balance wheel to the
At its other end the shaft Bis provided with a crank B³, which is furnished
with a wrist pin and friction roller B₁ playing in a grooved cross head B attached
to the needle bar B. This groove in the cross head is shown in dotted lines in
Figure 2 and is of the peculiar form indicated, so that a certain timing may be
given to the needle, as hereafter described in connection with the operation of the
shuttle and take up. Just behind or to the right of the crank plate B³, and upon
the same main shaft B is a cam B', shown in Figures 5, 6, 7, for operating the take
up. Cis the presser foot bar carrying the presser foot C, which is slotted to permit
the passage of the needle, turned up in front to allow the goods to feed beneath it,
and pressed down by a spiral spring on the bar C to hold the foot down to its work
with the yielding pressure desired and permit the feed to raise it from below. A
cam lever C2 on the left side of the casing A³ takes under a pin Cs, projecting
through a slot in the casing from the presser foot bar to raise the said bar and lock
it in the raised position. Projecting from the bar C at right angles to the pin C³
is a bearing plate C³, which comes out through a slot at the back of the casing and

page_text: sets against an adjustable guide C (Figure 9) to prevent or to take up any lateral
play the presser foot C¹ may have. Below the bed A there are two parallel counter
shafts D, E, (see Figure 4) both actuated from the main shaft B. The-shaft-D
receives.continuous or rotary motion for operating the feed, and the shaft E receives
_alternate_rotary_motion for operating the shuttle. Upon the shaft D there is a
tapering-cam-1-which is capable of sliding, but is prevented from turning on the
shaft by a spline in the cam and a slot in the shaft. The cam 1 is moved and held
-in-position-by a forked part-2, embracing a grooved part at the smaller end of the
cam and fixed to a tubular bar 3, which passes through the post 4, and is threaded
internally to receive an adjusting screw 5, which also turns in a post and has a
inilled head that projects slightly above the bed of the machine. Above the shaft D
lies the feed bar D', shown in side view in Figures 20, 21. This bar is slotted at
one end and a pivot passes through the slot. At the other end the bar D rests
upon a second cam D2 on the end of the shaft D. This cam D2 servos to raise the
bar whilst the first cam 1 strikes against a roller on an arm of the feed bar and
moves said bar forward. When released from the action of these cams a spiral
spring D (Figure 4) brings the bar down and back. This feed bar D' may be
made in two parts, an upper part and a lower part, against which the arm D²
bears, or it may consist of a single split bar, as shown at 6, Figure 21ª. When
made in two parts the upper one d³ carries the feed claw d' and the lower one d³
is connected to the upper part by a screw do
In either case a set screw 7 passes
through the upper part and bears against the lower part, so that by adjusting this
set screw the upper and lower portions may be sprung asunder more or less to give
greater or less height above the cloth plate to the feed claw d', thus effecting the
operation of the feed and giving it an additional adjustment.
The cloth plate has two slots to admit the feed claw d', and is apertured to allow
the needle to descend. The rotary shaft D and the rock shaft E are both actuated
from the main shaft B as follows:-Upon the main shaft B within the head of the
hollow standard A¹ is an eccentric F, surrounded by a strap F, connected to a
rod, whose other end is attached to a crank F3 on the shaft D. About midway
of the length of this rod F2 is a pin F which passes entirely through, and is
furnished at the back with a roller (or the roller may be omitted) which plays in
a vertically slotted guide F attached to the standard A To other end of this
same pin is connected a short connecting rod F³, whose lower end is attached to a
crank F7 on the rock shaft E. This mechanism gives the desired rotary motion to
shaft D, and rocking or alternate motion to shaft E. The amount of oscillation of
the rock shaft E may be varied by varying the throw of the crank F7 the length of
the connecting rod F, or the position of its upper attachment. The eccentric Fis
fixed to shaft B by one of two set screws fitting into indentations made in the shaft
slightly nearer together or farther apart than the points of the screws, so that by
-loosening one-screw and tightening the other the eccentric may be turned slightly
on the shaft so as to change the timing of the take up needle and shuttle to enable
either a tight or elastic stitch to be made.
**
The shuttle in this machine is caused to move in a curved line through the least
possible distance, only moving just far enough to clear the loop of the upper thread,
in other words, only a little farther than twice the length of the shuttle. The
shuttle operating shaft E passes through a stationary plate E, which is attached to
the bed plate A, and serves as the guide or
73
race for the shuttle. The shuttle
carrier E³ is fixed to the end of the shaft E. It consists of a plate with two horns
e, e, (Figures 5, 6, 7) and a centre bearing between which the shuttle lies close to
the shaft hub, so that the motion will not only be as short as possible but will also be
close to the centre, avoiding the shock incident to a long stroke. The needle comes
down to a little behind the centre of the shaft. The shuttle E, shown separately
in Figures 10, 11, 12, 13, 14, is constructed so that the bobbin E may be of the
largest possible diameter. It has two connected cylindrical cavities, whose axes
when the shuttle is in position in the machine are parallel with the oscillating
shuttle driving shaft. The larger cavity receives the bobbin E, and the smaller one

page_text: contains the tension device. There is a stud 7 in the larger chamber on which the
bobbin is placed; this stud has a slot in one side through its entire length, which
contains a spring for retaining the bobbin in position. The tension device consists of a
screw threaded stud 8 in the smaller cavity of the shuttle, and an internally threaded
sleeve 9, having a head nicked like a screw head placed thereon, and two centrally
apertured discs 10, placed on the said sleeve and pressed together and outward
against the head of the sleeve by a spiral spring 11 on the stud and sleeve. The
heel of the shuttle is cut away so that when the shuttle is in place in the machine
the line of the heel is approximately radial to the centre of oscillation of the shuttle
carrier. The thread froin the bobbin is let out under the head of the sleeve 9, and
between the discs 10. The tension is adjustable by screwing the sleeve against the
discs. From the discs the thread is led out through a hole in the shell of the shuttle
and passes beneath a guard e³, or as in the Drawing, the thread instead of being led
from the discs directly out to the guard, may be led back through the same hole into
the bobbin cavity and thence out through a delivery hole in the shell of the shuttle
to the guard e. This latter method ensures the thread from slipping out from between
the discs and loosening its tension. To guard against the shuttle being thrown out
of place, the race is provided with a circular or peripheral ledge E. This whole
shuttle race consisting of the plate and ledge is made separate from the bed plate in
order that it may be turned or formed on a lathe or machine inore conveniently, and
is attached to the bed plate by screws. The upper part of the ledge E is removed
to permit the thread to draw from either direction without coming into contact
with anything between the shuttle and throat plate. To hold the shuttle from
falling out sidewise under motion, a hinged cover G (shown in Figures 2, 22, 23) is
provided. This is secured to the race in an opening covered by a slide G2, by a
hinge pin which is surrounded by a spiral spring 12, that serves both to open the
cover, and to hold the nib 13 in engagement with the catch 14. This cover is
furnished with a spring E7, which bears against the shuttle when the latter is at
the back end of its stroke, in order to cause it to lie close against the face of the
race while the shuttle point is entering the thread loop.
The take up device which is shown detached at Figures 5, 6, 7, consists of a
jointed arm H, pivoted at its upper extremity to the inside of the hollow arm A,
at the end, and provided with a bearing roller h, just below the pivot against
which bears a cam B7 on the shaft. The joint H2 of the take up H contains a
spring which acts upon the lower portion of the arm with a tendency to throw it in
the direction indicated by the small arrow shown in Figure 5. Stops ², h³, limit
the motion or yield of this arm, causing it at this limit in either direction to become
rigidly a part of the upper portion of the arm. At this joint H2, shown enlarged at
Figure 8, a regulating disc H³ is applied, to which one end of the spring is secured
and the other end to the lower portion H4 of the arm H. The disc is turned and
set by a small screw to regulate the tension of the spring. The arm H works in
a long loop 15 on the casing A³, having at one end a leather pad standing in the
path of the take up arm and serving as a stop to said arm to cause the lower part
H' to unfold its full extent to determine the amount of stroke of the take up. The
take up strikes against the pad in its path in case the tension is too weak to cause
the thread to force the lower arm Hagainst its stop h². The needle thread proceeds
from the spool conveniently mounted upon the top of the upright standard A¹ to a
tension device presently to be described, thence to an eye J at the upper part of the
needle bar casing, thence under one of the studs J1 at the lower part of said casing,
thence through an eye in the lower extremity of the take up, and theuce back
over the lower stud J¹ through a guide J2 on the lower end of the needle bar to
the eye of the needle.
The tension device for the upper thread consists of a pair of plane or.corrugated
plates M, M, such as are in common use, in combination with a peculiar contrivance
acting as a check on the thread between said plates and the spool. The check
consists of a tube M', shown in longitudinal section in Figure 17, within which is
a bar M² pivoted at the rear end to M'. The upper part of the tube M³ is slotted

page_text: with a Tshaped slot, the stem of the T coming out to the mouth of the tube, while
the arms of the T are cut down at each side about half way across the tube. The
thread from the spool passes into the tube through one arm of the T slot, under the
bar M2, and out at the other arm of the slot, thence round between the corrugated
plates or revolving tension wheel M, and through an eye M³, from whence it is led
to the needle. The weight of the bar M resting upon the thread affords the
necessary check between the plates or wheel M and the spool to cause the thread
to be gripped sufficiently by the plates or wheel M. to cause the wheel to turn
when the tension is applied to the same-by a nut or-screw (not shown). But in
order to increase the pressure of the bar beyond its weight, and to afford a means
of adjusting the pressure, a spring m' is applied in a slot in the said bar, as shown
in the longitudinal sections of the bar, Figures 18 and 19: Said spring extends-
behind the point at which the bar M2 is pivoted to the tube, and a set screw m²
bears against the spring, whereby its tension may be adjusted, in order that by
acting from the bar against the tube behind the pivot it shall press the bar down
upon the thread with more or less force, according to the adjustinent of the screw.
Other kinds of springs than that shown may of course be employed with like
effect.
The operation and timing of the needle, the shuttle, and the take up may be best
described together and with the aid of the diagrams, Figures 5, 6, 7, as follows:-
Figure 5 shows the needle down through the cloth and just starting to rise,
causing by the difference in friction of the cloth upon the needle and the thread a
loop in the thread below the cloth. At this moment the shuttle commences to move
forward towards the loop, and at the same time the take up hangs vertically unin-
fluenced by its cam. The Drawing would seem to indicate in this Figure 5 that
the upper thread above the cloth is drawn tight into straight lines; this is really
not the case, as the thread at this time is slack and uninfluenced by the take up and
cam.
Figure 6 shows the shuttle in the act of passing through the loop; the needle is
still rising, but not having reached its highest point the lower arm of the take
up has yielded to the limit of its stop 13, this yield being caused by and provided
to accommodate the enlargement of the loop caused by the passage into it of the
shuttle. Figure 7 shows the shuttle at its lowest point and standing still, having
drawn its thread and set the stitch previous to its backward motion; the needle is
also at its highest point, and just starting down again. The take up is shown as
in the act of being thrown over by its cam, and has drawn the thread of the loop
up through the cloth and through the eye of the needle, tightening the upper
thread of the stitch. Thus in setting the stitch the eye of the needle is relieved of
all strain of the thread, which simply draws through the eye while the needle is
above the cloth. Of course it will be understood that the movements thus sepa-
rately shown in these three diagram Figures run into each other between the times
which these several diagrams indicate...
The motion of the needle bar, imparted to it by the peculiar shape of the groove
in the cross head heretofore alluded to is as follows:-The needle descends with a
nearly uniform speed, and commences to ascend without pause, but slackens its
speed for a little way on its upward course, then regains its former speed, the object
being to gain time for the shuttle to pass through.
Having described the nature of the Invention, and the manner of performing the
same, I declare that what I claim as the Invention to be protected by the herein-
before in part recited Letters Patent is,-
1st. The oscillatory shuttle carrier E3 and the circular peripheral shuttle race
E, E, in combination for guiding and carrying the shuttle, substantially as herein
specified.
2nd. The combination of an oscillatory shuttle carrier E3 and a shuttle E having
its heel or delivery end approximately radial to the centre of oscillation of the
carrier substantially as shown and described.
3rd. The oscillatory shuttle carrier E³, the circular peripheral shuttle race E², Eº,

page_text: having a cut away portion, and the shuttle E* having a curved side adapted to the
shuttle race, as specified.
4th. The shuttle E, the race E³, E, carrier E³, shaft E, the swinging spring acted
cover G, spring E7, substantially as specified.
5th. In combination with the shuttle E the slotted stud 7 containing a bobbin
holding spring, substantially as shown and described.
6th. The shuttle E*, having a cut away heel, and arranged to pass entirely through
the thread loop formed by the needle, and the take up mechanism turned to tighten
the stitch after the needle is above the cloth, both combined and operating together
substantially as herein specified.
7th. A take up lever made in two parts jointed together, and provided with an
adjustable extension spring and a stop device, substantially as herein shown and
described.
8th. The take up H, H2, H, shaft B, cam B7, loop 15, combined and operating
substantially as specified.
9th. The take up, having a joint H² containing a spring, the regulating disc H³,
and the limiting stops h³, h³, substantially as specified.
10th. The contrivance C5, C6, in combination with the presser foot for adjusting
the lateral movement of the presser foot bar, as shown and described.
11th. The bifurcated feed bar carrying the feed claw, and having adjusting screw
passing through one part and bearing against the other part, so that the feed claw
may be adjusted up or down, substantially as specified.
12th. The tension check, composed of two principal parts, a tube M' and a bar M²,
the tube being slotted across and longitudinally, and the bolt consisting of a bar free
at one end and pivoted at the other end, substantially as specified.
13th. The tension check, consisting of the slotted tube M³, pivoted bar M, and an
adjustable spring m¹ on the bar, substantially as specified.
14th. The mechanism for driving the two counter shafts D, E, from the main
shaft B, whereby an oscillating motion is given to one of the counter shafts and a
rotary motion to the other, said mechanism consisting of an eccentric F on the
main shaft, and a fulcrumed rod F connected to a crank on the counter shaft I), and
a shorter rod F connected with the fulcrum or pivot of the rod F2 and with a crank
on the counter shaft E, substantially as specified.
15th. The eccentric F having two set screws, and the shaft B having two
indentations located farther apart or nearer together than the points of the set
screws, substantially as and for the purpose herein shown and described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Third day of May, in the year of our Lord One
thousand eight hundred and seventy-nine.
A. M. CLARK. (L.S.)