Year: 1887

page_text: Date of Application, 19th July, 1887
Specification Accepted, 25th Oct., 1887
[Communicated from abroad by CHARLES GOODYEAR, Junior, of Boston, Mass.,
United States of America, Manufacturer.]
I, ALEXANDER HENRY REED, of Suffolk House, Laurence Pountney Hill, Cannon
Street, in the County of Middlesex, Engineer, 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 relates to improvements in sole sewing machines, and it consists in
embodying in such a machine novel mechanism whereby a lock stitch is obtained and
the outsoles can be stitched to the shoe through the shank regardless of the width of
the last, and while the shoe is on the last. The improved mechanism consists essentially
of an oscillating discoidal shuttle carrying one of the threads, a work support and
presser foot or channel gage, a looper below the work support, a loop retainer located
between the looper and the work support, a circularly curved, hooked needle,
which draws the loop through the material, a loop spreader which carries the
loop into the path of the shuttle a take up for drawing the thread off the shuttle
and a circularly curved awl which pierces the material in advance of the needle and
feeds the work, all of which is more fully pointed out in the following specification
and claims and illustrated in the accompanying drawings in which
Fig. 1 is a front elevation of a sole sewing machine embodying the invention.
Fig. 2 is a vertical section in the plane x fig. 1.
Fig. 3 is a similar section in the plane y y fig. 1.
Fig. 4 is a sectional view in the same plane showing the shuttle in a different
position.
Fig. 5 is a vertical section in the plane z z fig. 1.
Fig. 6 is a top view on a smaller scale than the preceding figures, of the feed
adjusting mechanism.
Fig. 6 is a section in the plane 28 fig. 6.
Fig. 7 is a section in the plane r¹ a fig. 1.
Fig. 8 is a vertical section in the plane y¹y' fig. 9 of the looper cam.
Fig. 9 is a top view of the same.

page_text: Figs. 10, 11, 12 and 13 are elevations showing the stages in the formation of the
stitches.
Fig. 10 is a perspective view of the loop retainer on a larger scale than the
previous figure.
Figs. 14 and 15 are detail views of the shuttle and shuttle driver.
Similar letters indicate corresponding parts.
In these drawings the letter A¹ designates the main shaft of the machine to which
a rotary motion is imparted by a suitable belt and pulley connection with a counter
shaft, and said main shaft A' carries hubs B, C, and D, having proper connections
projections, depressions, and grooves to correctly actuate the various parts of the
machine to produce the stitch.
The shuttle E is located above the work support J and is carried in an open case E¹
being arranged to turn about its centre therein. In the discoidal body of this shuttle
is formed a cell for the reception of the thread t which cell is closed by a cover e,
secured to the shuttle and lies to one side of the centre of the shuttle.
The thread is
led from the centre of the cell and through an eye in the centre of the shuttle, between
which two points, the thread is pressed upon by a tension plate e*. The shuttle is
actuated by means of a driver e¹ (figs. 14 and 15) which lies in the casing at the rear
of the shuttle and has a projecting portion or follower which engages with the
shuttle. A nose or hook e³ extending from the body of the shuttle takes up the lower
thread t¹ from the ball or spool as the case may be, such thread finally passing between
the body of the shuttle and the follower e³, and entwines the shuttle thread to form a
lock stitch.
The shuttle is held clear of the driver, so as to form a threadway between it and the
driver by a V, shaped guide e (figs. 3, 4 and 14) which is formed on the shuttle and
enters a corresponding raceway in the case E' so that the spool thread can be drawn
over the shuttle.
The proper oscillating motion imparted to the shuttle driver (fig. 3) by means of a
gear thereon which is engaged by a rack fat one end of an arm F that is pivoted
at to the frame, and the said arm has a roller stud which engages with a cam
groove b in the side of the hub B (fig. 2). By observing the course of this cam
groove b, the motion of the shuttle is apparent, viz: first it is turned in the direction of
the arrow 1 (fig. 10), then it remains at rest for a short period of time, and finally
it is turned in the opposite direction to arrow 1 (fig. 10), such motions and stop
corresponding to the taking up of the loop, the discharge of the same, and the return
of the shuttle to its original position.
The pressure foot or channel gage g has its shank or carrying bar g' fitted into a
groove in a carriage H so as to be moveable longitudinally, and it carries a stud which
is embraced by the bifurcated end of a lever G pivoted at g* and connected with a
spring to depress its rear end, which end carries a roller stud g², so as to hold this stud
in contact with the cam-shaped periphery of one edge of the hub C (figs. 1, 2, 5 and 7).
The spring acts to depress the rear end of the said arm and lifts the pressure foot when
the roller stud g³ comes to the depressed part-c (fig. 7) of its actuating cam, this lift of
the pressure foot taking place while the needle is in the material and so permitting the
pressure foot to be moved backward over the material after having been moved forward
to assist in feeding the material.
When the roller stud rests on the high portions c* of the actuating cam (fig. 7)
the pressure foot holds the material down to a certain determined level with relation to
the extreme upward pull of the needle, notwithstanding variations in the thickness. of
the material being sewed.
The carriage H previously mentioned is provided with a guide block extending at
right angles thereto, and which is fitted in guideways formed in a rigid housing. H¹
that eonsititutes part of the frame of the machine (figs. 1. 5. 6 and 7). To move, the
carriage H in and out, so as to feed the material, a lever H is used which is pivoted
to the housing H¹ and is provided at one end with a roller stud h' that enters a cam
grooved in the hub D, so as to vibrate said lever Habout its point of pivoting.

page_text: 21
This lever is slotted at or near its central portion (fig. 6) and in this slot plays a
stud h², the lower end of which is extended into a grooved block h³ (the groove being
shown by dotted lines in fig. 6) that is rigidly attached to the guide block h of the
carriage H. The carriage, at the lower end of its vertical portion, has attached
to it a pivot (fig. 7), which supports the awl carrier or awl segment I, so that as the
carriage is moved transversely the circularly curved awli being in the material is
made to act as a feeding device. The awl segment I and the awl are oscillated by a
rack at one end of an arm I¹ pivoted at 3 to the frame, and said arm I' has a roller
stud which enters a cam groove c', in the hub C (said groove being shown in dotted
lines in fig. 7). The teeth of the rack are made wide enough to remain constantly
in engagement with the teeth of the awl segment I, as it is moved laterally with the
carriage H, each time the material is fed, the work plate or support J having a long
slot for a throat to permit this lateral motion of the awl.
The circularly curved needle k is attached to a needle segment K, which is
mounted on a pivot k¹(fig. 3) that is secured to the frame A, and said needle segment
is oscillated by a toothed driving segment which swings about a pivot K2 and carries
a roller stud k³ which enters a cam groove 6' in the hub B. A depression d in the
cam groove gives the needle a slight "dip" as the shuttle takes the thread, so that
the same is readily released from the needle.
The needle and awl turn about centres arranged in one and the same straight line,
but at a distance apart, so that as the work is fed forward by the awl, the puncture
formed thereby in the material is brought in line with the needle. It will also be
observed that the needle acts from above, whilst the awl acts from below the work
support, that is to say they act in opposite direction.
The needle guide or support k is carried by a sector K*, the teeth of which engage
with a pinion mounted on a short spindle upon the outer end of which is a split
collar (figs. 1 and 2) that has an arm subjected to the action of a spring ² which
constantly keeps the needle guide pressed as close to the work as possible, in such a
manner that it follows with the needle as the same moves toward the material, and is
returned by the action of the projecting lug on the needle against the guide or
support, on the return of said needle.
The discoidal shuttle E is located above the work support and oscillates in a plane
at right angles or nearly so, to the plane of the path of the needle, that is, the path
of the shuttle lies outside of the path of the needle, but as seen by inspection of figure 3
the needle segment is larger in diameter than the arc in which the needle oscillates,
and therefore the paths of the shuttle and needle segment intersect. To permit the
parts to pass, a proper recess e is formed in the shuttle, through which the segment
extends as the needle penetrates the material and during the period of time in which
this takes place, the shuttle, owing to the contour of its actuating arm, remains
stationary.
The narrow work support J (figs. 1 and 5) projects from a bed J¹ which is pivoted
at to the frame A of the machine, and said bed J' is provided with an arm ji which
is engaged by a slide bar J', held or directed in its longitudinal movement by a guide
box (fig. 5). A strong spring JB connected with a rigid stud j³ and a connecting
rod attached to the slide bar J acts to force the work support firmly against the
4
material.
The work support J in contact with the usual welt of the boot or shoe, is auto-
matically locked in position during the time that the needles penetrates the material,
and while the pressure foot is moved backward from its forward position, immediately
after which, and as the pressure foot is descending upon the material, the support is
unlocked to permit the same to rest in the channel of the outer sole, and to place the
bottom of the channel always at the same uniformn level, the support then yielding to
compensate for all variations in the thickness of the material. After the pressure
foot is depressed, the needle is raised from the material, but just before it leaves the
material, the support is again locked and is held thus while the awl pierces the material
and until the feed takes place. The locking device to hold the support or its bed J'
rigidly in position, is herein shown as a lever L which is pivoted at 7 to the frame A and

page_text: carries a roller stud l which is in contact with the cam surface of the hub D. A
spring constantly presses the roller stud against this cam surface which has two
depressions d' d' so that the lever L is vibrated twice for each revolution of the cam,
causing the pawls on its forward end to engage with ratchet teeth formed on
the sliding bar J so as to hold it in place, that is, prevent it from moving backward.
During the time that the lever L is not in engagement with the teeth on the sliding
bar J³, the work support is free to yield.
In order to depress the work support for the insertion or removal of the work, a
hand lever M is pivoted to the frame at m and is in engagement with a pin or stud m²
projecting laterally from the bed J', so that by pressing the hand lever inward, the
work support is lowered. A spring m² returns the hand lever to its original
position.
It will be observed however, that the work support can only be lowered when the
hub D is in certain positions as explained.
The looper N (figs. 1, 3, 10, and 11) having the usual eye is located beneath the
work support and is secured to an arm N₁ which arm N' is attached to one arm of a
bell crank lever N that carries on its other arm a roller stud n which is in contact
with a cam on the hub B. The bell crank lever is pivoted at o to a swivel bar O
which is pivoted at o' to the frame, and has supports o² for the arm N' which carries
the looper N. This bar O carries a roller stud o³ which enters a cam groove 1ª in the
hub B, the course of which cam is clearly shown in figs. 8 and 9, and causes the bar
to vibrate and imparts to the looper a motion from one side of the line of needle to
the other. The cam engaged by the roller stud n of the lever N2 has a projection 6³
which causes the arm N₁ to be thrown in and out, thus giving the looper a motion in
a direction at right angles to the motion imparted thereto by the bar O. A slot in
the arm N' allows this arm N' to be moved freely, and a spring attached to the crank
lever N2, constantly keeps its roller stud n against the cam.
To the frame A, and between the looper and the work support is attached a loop
retaining device P which consists of a rigid plate or prong p to which is secured a
spring blade p¹, so that this device will retain the thread if said thread is inserted
between its parts. In order that the looper may readily insert the thread into this
loop retainer a small lip p projecting downwardly, is formed on the spring blade p²,
which is impinged upon by the looper to force the spring blade apart from the rigid
plate, so that the thread can enter between the two parts. The object of this loop
retainer is to provide a supply of thread, which is taken up through the work by the
needle without sliding in the eye or barb of the same, while it is passing through the
work. The action of the looper due to the combined action of the arm and swivel
bar is first to lay the thread in the loop retainer P, which holds the thread until
pulled away from it by the needle, then to lay the thread in the eye of the needle, then
to the right of the line of needle, and finally back to its normal position, as shown in
fig. 1.
The loop held by the loop retainer P is drawn upward through the material by the
needle, and to bring said leop in proper position to be taken up by the shuttle nose
or hook e, a loop spreader or lifter R is used which has a tongue or lip p; which
extends parallel or nearly so to the face of the needle segment and in a plane outside
of the plane of the same. The hook of the loop spreader lies under or within the
inner periphery of the needle and is actuated to move in a perpendicular direction
across the path of the needle, that is to say across the arc of vibration of the same,
and receives the thread from the needle and spreads the loop so that the shuttle nose
or hook will pass through it.
One of the functions of the loop retractor, lifter and spreader is to draw sufficient
loop after it is released from the needle hook, so that the shuttle may pass through
the loop without the shuttle being necessitated to pull up its own thread.
In the example shown in the drawing (fig. 3) the loop spreader R is attached to
the free end of an arm R' which is pivoted at to the frame A, and carries a roller
stud that is in peripheral contact with the cam face on the hub B. This hub has
a long projection 6* so that when the roller stud 2 rides on said projection, the loop

page_text: spreader is drawn upwards. A spring keeps the roller stud constantly in engagement
with the cam face (fig. 2 and 3).
On inspection of fig. 4 it will be perceived that loop spreader R engages the loose
thread leading from the looper N to the barb of the needle and carries such strand
of the loop upward, so that the shuttle passes by and in front of the portion of the
loop nearest to it and takes up the thread on the side of the needle furthest away,
and therefore the shuttle acts on that part of the thread, which leads from the take
up mechanism through the looper to the barb of the needle. The shuttle then
disengages the thread from the needle, without drawing the thread through the barb,
that is, it is slipped off the barb.
To draw the thread t¹ off the shuttle at the proper time a "take up" device is
used which in the example shown in this drawing consists of a bell crank lever S
that is secured to a spindle s having bearings in the frame A and said bell crank
lever carries on one arm a pulley S¹. A second pulley S2 is carried by an arın ¹
which is mounted on the spindle & but can turn independent of the same, and over the
two pulleys S¹ S is passed the thread from the wax chamber, said thread first passing
around a tension wheel U having bearings in a frame at the back of the machine.
The arm s¹ is acted on by a spring s³ and carries a stop S₁ (fig. 2) which abuts against
the frame. An arm S³ extends also from the take up lever S and has a nut for an
adjusting screw so that the are of vibration of the take up lever S can be regulated
for varying thickness of material and length of stitch. To actuate the take up lever
at the proper moment, its vertical arm is connected by a link v, with an arm V,
(fig. 2) that is swung on a spindle ¹ from the frame A and is connected by a link v²
with a lever V', that oscillates about the spindle v¹ and carries a roller stud v³ on the
end of its free arm.
This roller stud 3 bears on a heart cam V' that is secured to the
main shaft A' of the machine and is held in contact with the same by a spring v
extending to the frame.
The spindle of the tension wheel U carries two toothed wheels uu (fig. 5) which
are adapted to be engaged by pawls u u¹, said pawls being acted upon by springs
swung on either side of a lever U₁, that is pivoted at u' to the frame, and carries on
its inner end a roller stud u³ that bears upon a cam face formed on the hub D, said
cam face containing a projecting portion d³ which engages the roller stud to raise the
pawls u u clear of the toothed wheels u u so as to permit the withdrawal of the
thread at the proper time, that is to say, when the lifter or shuttle takes up the loop,
but is locked when the take up is drawing the loop downwards. A spring ut keeps
the roller stud in contact with its cam face at all times. The spring pressed arm and
its pulley S3, takes up the slack formed by the looper, owing to the action of the
spring.
The general operation of the machine in forming the stitch is as follows: The
threads being properly arranged, the work is inserted between the presser foot and
the work support, the latter being first drawn downward to facilitate its introduction.
Referring at present to figs. 10, 11, 12, and 13, the awl (fig. 13) first moves upward
and pierces the material, and while it is in the same the feed takes place, which brings
the puncture in line with the needle. As the needle approaches the puncture the awl
recedes, and after the needle has penetrated the material, the pressure foot and awl
return to their normal position. At the same time the looper carries the thread to
the loop retainer, and as the needle projects beyond the material, the looper crosses
the needle and lays the thread in its barb or hook. The needle now draws the loop
through the material (fig. 10) after which the proper strand of the loop is grasped by
the loop spreader, which had previously been lowered within the arc of oscillation of
the needle. The loop spreader now rises and brings the loop within the reach of the
shuttle, the nose of which enters the looop and draws it over the shuttle
(figs. 4, 5 and 12). The shuttle continues to move until in the position shown in
fig. 11 in which position it remains stationary until the loop is drawn over the shuttle
by the action of the take up, and entwines the shuttle thread whereby a lock stitch is
formed,

page_text: When sewing the shank of the shoe or boot, it is desirable to make the stitches
longer than when sewing about the fore part of the shoe. To be able to quickly
change from the maximum length of feed to the minimum or the reverse, and
insure like length of stitches on all work of certain sizes, the pin h³ (fig. 6) in the
slotted lever H2 is placed under the control of a feed regulator H³ pivoted at
so that the pin by shifting said regulator is caused to traverse the slot in the lever H³,
and is placed at a greater or less distance from the fulcrum pin of the said lever
according as the feed is to be long or short.
Near the regulator H³ is a plate H* provided with holes, in any two of which may
be placed the adjusting pins h³ he, two being used at a greater or less distance apart,
so that when the regulator rests against the pin h or feed stop, the feed will be short,
and when against pin A long. The change of feed is made instantly by throwing the
regulator against one or the other stop. A guard N* prevents the upper of the shoe
from interfering with the motion of the looper.
If it is desired that the lock of the thread (where one thread interlocks with the
other) should be done with precision at any particular depth below the surface of the
leather, this may be accomplished by methods other than those already described.
One method is to connect a " take up
"mechanism with an arm of the lever which
supports the moveable table or support for the work by means of a connecting rod or
link in such manner that while not interfering with the motion of the "take up" yet
the supply of thread drawn from the ball (as distinguished from the shuttle thread) is
governed by changes in the position of the table or support for the work according
as the stock is thick or thin, giving off more thread for the thicker stock and less for
the thinner. In this arrangement the thread passes over two stationary thread rolls
in front of the machine underneath the work support and a vibrating lever is
arranged between said rolls in such manner that when the thread is being drawn
from the ball one end of the vibrating lever impinges upon the forward thread roll
and holds the thread fast on that side, and when the stitch is being tightened the
other end of said lever impinges upon the other thread roll and prevents any
more thread being drawn from the ball until the next stitch is taken. In this
arrangement a double "take up" is used, one for drawing off a sufficient supply of
thread to form the stitch, the other to tighten the stitch after the shuttle has passed
through the loop.
Having now particularly described and ascertained the nature of the said invention,
and in what manner the same is to be performed, I declare that what I claim is:
1. The combination in a lock stitch sewing machine of the work support, an
oscillating barbed or hooked circularly curved needle, an oscillating discoidal shuttle
arranged above the work support, an awl, and means for giving the awl a lateral
movement while in the material whereby it operates as a feeding device, substantially
as described.
2. The combination in a lock stitch sewing machine, of the work support, an
oscillating shuttle arranged above the work support an oscillating circularly curved
aw an oscillating circularly curved needle, mechanism for moving said awl and
needle in opposite directions and a longitudinally moveable presser foot or channel
gage operating with the awl in feeding the work, substantially as described.
3. In a lock stitch sewing machine, the combination of the oscillating circularly
curved hooked needle, a needle guide or support, a discoidal shuttle oscillating around
its own axis in a plane at right angles, or nearly so, to the plane of the needle, and a
looper, substantially as described.
4. In a lock stitch sewing machine, the combination of the oscillating circularly
curved hooked needle, and a discoidal shuttle oscillating around its own axis in a
plane at right angles or nearly so, to the plane of the needle, and having a hook
moving in a path which does not intersect the path of the needle, substantially as
described.
5. In a lock stitch sewing mechanism, the combination of a circularly curved

page_text: needle and a circularly curved awl mounted in toothed lever segments of larger
radius than the radius of the needle and awl, with a discoidal shuttle oscillating in a
plane at right angles or nearly so, to the plane of the needle, and having a hook
moving in a path which does not intersect the path of the needle, substantially as
described.
6. In a lock stitch sewing mechanism, the combination of a circularly, curved,
hooked needle, a discoidal shuttle operating at right angles to said needle a hook
formed on said shuttle, and a loop retractor or spreader for carrying the loop into
the path of the shuttle hook, substantially as shown and described.
7. In a lock stitch sewing mechanism, the combination of a circularly curved, hooked
needle having an oscillating motion, a discoidal shuttle oscillating in a plane at right
angles or nearly so, to the plane of the needle, a loop retractor or spreader having a
path intersecting the path of the needle, and means substantially as described for
imparting to said loop retractor a reciprocating motion in a plane parallel or nearly
so, to the plane of the needle, substantially as described.
8. In a lock stitch sewing mechanism, the combination with a circularly curved,
hooked needle, a discoidal shuttle, a hook formed on said shuttle, a looper for
conveying the thread to the needle, a loop spreader or retractor and means to cause
the said spreader to engage that strand of the loop which leads to the looper and to
carry it into the path of the shuttle hook, substantially as shown and described.
9. In a lock stitch sewing mechanism, the combination with a work support and
with a circularly curved hooked needle having a rotary, reciprocating motion, of a
discoidal shuttle having an oscillating motion in a plane at right angles or nearly so,
to the plane of the needle, a hook formed on said shuttle and made to move in a path
not intersecting the path of the needle, a looper beneath the work support for
conveying the thread to the needle, a loop spreader above the work support and
means to cause the said spreader to engage that strand of the loop which leads
directly from the eye of the needle to the looper and to carry it into the path of the
shuttle hook substantially as described.
10. In a lock stitch sewing machine, the combination of a work support, an
oscillating circularly curved hooked needle, a circularly curved awl, means for moving
the awl and needle in opposite directions an oscillating discoidal shuttle operating at
right angles to the needle and arranged above the work support, a hook on the
shuttle for taking up the lower thread, and take up mechanism below the work
support for drawing the loop off the shuttle, substantially as described.
11. In a lock stitch sewing machine, the combination of a work support, an
oscillating circularly curved hooked needle, an oscillating awl, an oscillating discoidal
shuttle arranged above the work and having a hook, a loop retractor or spreader for
carrying the loop in the path of the shuttle hook, a take up mechanism below the
work support and means, substantially such as described, for drawing the loop off
the shuttle and yielding when the shuttle takes up the loop, as set forth.
12. In a lock stitch sewing mechanism, the combination of a circularly hooked
needle, a discoidal shuttle, a hook formed in said shuttle, a looper, a loop retainer, a
loop spreader having a reciprocating motion in a plane parallel to the plane of the
needle and intersecting the path of said needle for bringing the loop into the path
of the shuttle hook, and a take up for drawing down the loop to form the stitch after
said loop has been taken up by the shuttle substantially as described.
13. In a lock stich sewing mechanism, the combination with a circularly curved,
hooked needle, an oscillating shuttle moving in a plane at right angles to the needle,
a hook thereon moving outside of the plane of the needle, and a loop spreader or
retractor noving up and down in a plane parallel to the needle and intersecting the
path of the needle, to receive the thread from the needle, and place it in the path of
the shuttle, substantially as shown and described.
14. In a lock stitch sewing mechanism, the combination with the circularly curved,
hooked needle, having an oscillating motion, an oscillating discoidal shuttle rotating
in a plane at right angles to the path of the needle, a hooked formed on said shuttle
and moved in a path not intersecting the path of the needle, a loop spreader or

page_text: retractor, an arm bearing said loop spreader, and a cam operating said arm and which
imparts a rising and falling motion to the same, substantially as shown and described.
15. In a lock stitch sewing mechanism, having a circularly curved, hooked needle
and an awl working in opposite directions, the oscillating shuttle E, above the support
for the work, the shuttle driver for the same, a driving shaft extending from said
driver and operated by a lever segment and a cam; causing said lever segment to
rotate the shaft; substantially as shown and described.
16. In a lock stitch sewing mechanism, having a circularly curved needle and a
circularly curved awl and means to turn said needle and awl about the same center
line but in opposite directions, the combination of an oscillating shuttle and a shuttle
driver mounted upon a shaft extending from said driver at right angles to the center
line of the needle and awl, substantially as shown and described.
17. The combination with the oscillating shuttle and loop forming and spreading
mechanism, of the swinging take up bell crank lever S, carrying the pulley S', the
pivoted arm s¹ carrying the pulley S³, the link connected with one arm of the bell
crank lever, the vertical swinging arm V connected with said link, and means for
actuating said vertical swinging arm substantially as described.
18. The combination with the oscillating shuttle, the loop forming and spreading
devices and the work support of the take up lever S, directly below the work support,
the pulley S', carried thereby, the spring supported arms the pulley S thereon, the
adjustable stop on the take up lever and means substantially as shown and described
for actuating the take up lever from the rear of the machine, substantially as shown
and described.
19. In a lock stitch sewing mechanism, the combination with a circularly curved,
hooked needle having an oscillating motion, a discoidal shuttle having an oscillating
motion, in a plane at right angles to the plane of the needle and with loop forming
and spreading devices, of the take up lever and its pulley and the tension wheel
having means to enable it to be free to rotate when the shuttle is taking up the thread,
substantially as shown and described.
20. In a lock stitch sewing mechanism, the combination with a circularly curved,
hooked needle having an oscillating motion, a discoidal shuttle having an oscillating
motion, in a plane at right angles to the plane of the needle and with the loop forming
devices, of the tension wheel at the rear of the machine, a toothed wheel or wheels,
connected with the tension wheel, a lever carrying a pawl or pawls engaging with
said toothed wheel or wheels and a cam for oscillating said lever, substantially as shown
and described.
21. The combination with the shuttle and the needle of the loop retainer P, the
looper N, the cam surfaces engaging the roller studs on a swivel bar and bell crank
lever, to impart to the looper a motion toward the loop retainer and across the needle,
substantially as shown and described.
Dated this Nineteenth Day of Jul 1907