Improvements in wax-thread sewing m
Year: 1895

page_text: Date of Application, 8th Jan., 1895-Accepted, 9th Feb., 1895
Improvements in wax-thread sewing m
I, EARLE HENRY SMITH, of 121 Nassau Street, in the City and State of New
York, United States of America, Mechanician, 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:-
My said improvements relate to wax-thread sewing machines wherein a rotary
shuttle or loop-taker having a non-rotating thread-case, co-operates with a needle
and awl in forming the lock-stitch; according to my invention these parts are
combined in operation with separate devices for actuating the needle and awl;
and with positive means of holding the thread-case at rest while the loop-taker
revolves.
To illustrate the invention I have shown the same herein as developed in a form
of a machine using a circularly curved eye-needle, and this with special reference
to sewing on the soles of boots and shoes while on the last; but the invention is
applicable in machines using a crochet needle; also for stitching harness and other
leather work where a straight needle is employed.
In the drawing,
Fig. 1 is a front elevation of a shoe-sole sewing machine embodying my
improvements.
Fig. 2 is a side elevation viewed from the left hand side.
Fig. 3 is a side elevation as viewed from the right.
A, designates a suitable base upon which are erected two uprights B, B',
providing bearings for the main-shaft C from which motion is given to the operative
parts of the machine. B2, B3, are standards rising from the base; to one of
which, B2, is secured a stud a that forms a bearing for an oscillating segment C
which carries a circularly curved needle b. Said needle-carrier is oscillated by a
lever C, pivoted at the rear to a post d, and connected by a link (dotted in Fig. 3)
or other suitable means to the segmental needle-carrier. The lever C is provided
with a roller-stud d' engaging a suitable cam groove in the cam D, whereby the
required motion is imparted to the needle. The needle is guided and directed by
an ordinary movable needle-guide c having a perforation at the outer end, through
which the needle passes, and the guide is operated in any usual manner to follow
the motions of the needle.
The work being sewed rests on a proper support, here consisting of a curved
arm G, made fast to the standard B2; and is held upon said support by the presser
foot h, secured to the presser bar H.
The machine forms the lock stitch, by the co-operation of the needle with a
thread-carrying loop-taker, by which term is meant a rotary shuttle or hook, that
revolves around a bobbin contained therein. The loop-taker preferably used, is
a rotary shuttle S, adapted to run in a circular race or ring O, and is propelled
by a driver w, set on a driver-disc w¹ and engaging the shuttle by a notch in the
The driver-disc is
edge thereof leaving space around for the thread to pass.
affixed to a short driver-shaft S' which has a rotary motion imparted to it in one
direction only. The shuttle S is provided with a non-rotating thread-case T,
containing the shuttle-thread. The thread-case is hung loosely in the shuttle, as
by a pin in the center, or otherwise, and is thus independent of the rotary motion
of the shuttle, whereby it may be held at rest while the shuttle revolves. The
shuttle-thread, is delivered through an eye in the end of a projection t¹ termed

page_text: a leader, and thence to the under side of the work being sewed. The leader th
is secured to the thread-case, but extends beyond and holds the shuttle-thread
delivering-eye away from the path of the shuttle's point; it also serves to keep
that portion of the shuttle-thread reaching from the leader to the work, out of
the way of the needle. An instrument is used for puncturing the work for the
entrance of the needle, and is here represented by the awl f, which is made of
the same form as the needle, and plays up and down on the side of the thread-
leader, in line with the needle, thus avoiding interference with the shuttle-thread.
Positive means are employed to hold the thread-case at rest and prevent the
same from revolving with the shuttle, here represented by a check-bar t² pivotally
attached to the frame of the shuttle race, being held in place in front of the thread-
case, by a latch t³.
When the check-bar is in place, it is on the side of the
shuttle-thread leader opposite to that where the awl plays, so as to be out of
the way of the needle and awl, and between such leader and a stop-lug t, leaving
space for the needle-thread loop to pass off when the loop is being drawn up after
the shuttle has passed through.
The thread-case may be removed to insert a bobbin, by undoing the latch t
and turning down the check-bar t².
The main-shaft has a uniform rotary motion; but imparts variant or alternately
fast and slow motions to the rotary shuttle by intermediate mechanism. Such
variant motions are here made to occur twice in every revolution, and are hence
called, "duplex." These comprise short and long periods of acceleration, with
short and long intervals of slow motion between such accelerations, all occurring
during the same revolution. A short quick motion of the shuttle occurs when the.
shuttle's point advances to take the loop from the needle and the short interval
of slow motion immediately follows. After this occurs a longer acceleration, for
the purpose of passing the shuttle through the loop of needle thread quickly,
resulting in a correspondingly long slow or retarded motion of the shuttle, thus gaining
a sufficient interval of time in each revolution, during such slow motion of the
shuttle, for closing up the loop, and finishing the stitch, before another loop is
taken from the needle.
In the
The variant motions described may be obtained in a variety of ways.
drawing, U is a pitman pivoted at a point between its ends, and shaped at the
upper end to embrace an eccentric U', affixed to the main-shaft C; at the lower
end, this pitman carries a sliding block u, playing within a groove in a crank arm u
affixed to a second shaft S³. By this arrangement, the lower end of the pitman
is made to describe an irregular shaped orbit or path around the axis of the latter
shaft; and the parts are so disposed as to bring the orbit into eccentric relation
to said shaft, thus imparting to the latter the variant motion, which motion is
transferred to the shuttle by gearing consisting of a spur wheel son shaft S²,
meshing into a like wheel s on shaft S. Such variant motion is compounded and
intensified by another contrivance, that is to say: the pitman is fulcrumed to a
radius bar u, connected to one end of a lever U2; which lever is pivoted to the
standard B, and provided at the other end with a roller stud u³, entering a cam-
groove in the revolving cam-plate D, which cam, by moving the pitman's fulcrum
to and fro, varies the eccentricity of the said irregular orbit as to the axis of
shaft S. Thus by the co-operation of two variant speed devices, viz. the pitman,
and the cam-groove governing its fulcrum, the shuttle receives a compounded
differential rotary motion, and the accelerated motion thereof when passing through
the loop of needle thread is augmented.
:
The movements of the shuttle, as operated by the mechanism described, are as
follows: Beginning with the needle in position to present a loop of thread for the
shuttle, the shuttle advances with a short quick acceleration and takes the loop on
its point. As soon as the point of the shuttle has entered the loop, the motion of
the shuttle is momentarily slowed or retarded, to accommodate the action of the
needle which follows; thereupon, the needle being out of the work, the shuttle
motion is again accelerated, and so continues during 180 degrees, that is, half its

page_text: revolution, when it will have passed through the loop; thereafter the shuttle's
motion is retarded, and is very slow for a correspondingly long interval, until
completing the revolution.
The acceleration of the shuttle when passing through the loop of needle thread,
is so swift that 180 degrees, i.e., one half its revolution, is accomplished while the
main-shaft C, moving uniformly, makes about 70 degrees of its own revolution.
As a result, there remains a considerable interval of time during such slow or
retarded motion in which to draw the loop of needle thread from the shuttle to
finish the stitch, and for the awl to puncture the work before another stitch is
begun.
The awl, Fig. 3, corresponds in form to the needle, and is secured in a
segmental carrier F, (see dotted lines in Fig. 2,) adapted to oscillate on a stud f¹
placed directly opposite and in the same axial line, as the stud a on which the
needle carrier oscillates: the awl is disposed to enter the work from the side
opposite to that from which the needle enters; and the segment F which carries it
is actuated by means independent of that for operating the needle-segment, in this
case by a lever F', pivoted at its rear end, to the post d, and having at the front a
cogged-rack which engages with teeth formed on the segmental awl carrier,
(Fig. 2). This lever F¹ is operated from a groove of the required configuration
in a cam (D) on the main-shaft, being situated directly behind the standard B³, and
is entirely distinct from the cam D which actuates the needle operating lever, C².
A cam-moved device is used for delivering a loop of needle thread to and drawing
the loop from the shuttle at every revolution, (finishing the stitch in advance of
the operation of the awl and before taking another loop from the needle,) here
consisting of a thread-lever P located on the opposite side of the work from the
shuttle, and operated positively by a cam-groove in a cam D³ on the main-shaft.
The said thread-lever works in connection with a slack-thread take-up lever, R,
here made of a bell-crank form. The inner arm of the take-up lever carries a
roller r, resting upon a proper cam surface on the needle-cam D Fig. 1. The end
of the outer arm is perforated to receive the needle thread, and it rests on an
adjustable stop on the presser bar, except when under the control of said cam.
The cam raises the outer end of the take-up, to relieve the thread during the
action of the thread-lever. By means of the said stop on the presser bar the slack
is automatically controlled by the take-up, whose action varies with the rising and
falling of the presser-bar, according to variations. in thickness of the work passing
under the presser-foot.
The work is fed or advanced to space the stitches by any competent device.
For this purpose it is given a lateral movement when in the work. To this end,
the awl carrier stud f, is made last in the lower extremity of a hanger g forming
part of a sliding bar H¹ called a feed-slide, arranged to move in horizontal ways h
in a housing at the top of the standard B. The movement of the feed-slide H¹
is parallel to the axis of motion of the needle and awl, and said feed-slide is
operated from a lever H2 pivoted to the housing and connected to the feed-slide,
said lever having a roller at the end engaging a cam-groove ³ in the cam D³
(Fig. 1).
The presser-bar H, carrying the presser-foot, is secured to one end of a spindle i
which spindle is journaled in a tubular bearing made fast in the frame of the
machine.
To resist the upward thrust of the awl in puncturing the work, provision is made
for automatically locking the presser-foot fast at the time, and for subsequently
releasing it; the means of locking said foot fast, is a locking-lever L, Figs. 1 and 2;
it is provided with spring pawls at its front end, (omitted in Fig. 3) which
engage ratchet teeth formed at the top end of the presser-bar H: at its rear end
the locking-lever carries a roller stud which is held to the periphery of the awl
cam D', as by a spring. The periphery of this cam, normally maintains the rear
end of the locking lever in the position shown, to hold the pawls down; and in the

page_text: .
return movement of the awl after the feeding action, a depression n, in said cam
acts to lower that end of the lever, and raise the outer end enough to disengage
the pawls from the presser-bar teeth so as to permit the foot to accommodate itself
to increased or decreased thickness of the work, as the sewing progresses; afterwards
the foot is locked fast during the puncturing action of the awl, and the pull-up
action of the thread-lever, in completing the stitch.
The spring pressure of the presser-foot upon the work is made by a spring j.
Means of varying the pressure of this spring are shown in Fig. 3, which consist in
attaching the spring by one end to an arm j' made fast on the outer end of the
spindle and attached by the other end to the upper extremity of a lever M, that
is pivoted at m to the standard B³; such lever having at the lower end a roller-
stud m¹ which bears against a peripheral cam surface m² on the cam D2, by which
cam surface the tension of the presser-foot spring is varied at stated times to
increase and decrease the spring pressure of the foot. The locking-lever Lis
mounted to vibrate freely on an eccentric J seen in section in Fig. 3, which
eccentric is fixed on a headed arbor ³, journaled in an upright ; and said arbor
carries a handle whereby it may be turned on its axis. In the head of the
arbor there is a screw k, and the upper end of the presser-bar is connected to this
screw by a link A¹.
For lifting the presser-foot to insert or take out the work, the operator turns the
arbor by the hand-lever 13, and this causes the eccentric on said arbor, to first
raise the outer end of the locking-lever L, and disengage the pawls therein from
the teeth in the top of the presser-bar; then by the further turning of the arbor J,
the screw (acting as a crank-pin), and the link k', are caused to lift the presser-bar
(and foot) by said link.
k
The foregoing description refers to a machine using an eye-needle, in which
machine the shuttle is on the opposite side of the work therefrom. When a crochet
or hook-needle is used, the needle and awl change places, bringing the needle on
the same side of the work as the shuttle. In operation, the hook-needle is thrust
up through the perforation made by the awl; an ordinary thread feeder lays a
bight of thread in the barb of the needle; the needle then draws down the thread
as a loop, and the shuttle advancing with its first quick motion seizes it. When
the shuttle's nose has entered the loop, the brief slow motion takes place while the
needle is given a slight movement toward the work to disengage the loop from the
barb of the needle, after which, the needle is quickly drawn back out of the way,
and the shuttle passes through the loop in its long period of acceleration; the loop
is then drawn from the shuttle by the thread-lever in the manner before described
and the stitch completed.
The needle thread passes from the usual wax-pot (not shown) to the tension Q,
thence to the pull-up lever P, thence to the slack take-up R; thence it passes
to the needle; or instead, to a thread feeder, when a crochet needle is used.
In the operation of the needle and awl, it is the practice, (especially in sewing
the welts of shoes) not to force the awl entirely through, but to leave a portion of
the puncture to be completed by the needle: wherefore, the needle is in all cases a
piercing needle.
I expressly declare, that I do not restrict myself to particular forms, or special
construction, where these may be varied within the invention. On the other hand,
the gist of my invention resides in combinations, rather than in the novelty of the
elements of such combinations, severally considered.
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. The combination with the needle, mechanism for operating the same, and a
rotary shuttle or loop-taker co-operating with the needle, of rotary motion
mechanism imparting a duplex variable motion to said loop-taker in every

page_text: revolution, comprising a short period and a long period of acceleration, and short.
and long intervals of slow motion between such accelerations, as set forth.
2. The combination with the eccentric on the main-shaft, of a pitman fulcrumed
to a radius-bar, a second shaft, a crank-arm thereon grooved to receive a
sliding block worked by the pitman; the said radius-bar being connected to one
end of a lever U2 pivoted to the standard B, and having at the other end a roller-
stud entering the cam-groove of a revolving cam, as described.
3. In combination, a needle, a rotary shuttle, means of reciprocating the needle,
and mechanism constructed and arranged for rotating the shuttle with a variably
accelerated motion, such mechanism comprising two speeding devices arranged to
co-operate as described, whereby such accelerated motion is augmented when the
shuttle is passing through the loop.
4. The combination with the main-shaft rotating uniformly, a needle, a rotating
shuttle or loop-taker, and an awl to puncture the work for the needle, of
accelerative mechanism constructed and arranged to drive the shuttle through
180 degrees of its circuit within a space of about 70 degrees more or less, of the
main-shaft's uniform revolution.
5. In a wax-thread sewing machine, the combination of a circularly curved
piercing needle, means for reciprocating the same, a circularly curved awl, a
thread carrying loop-taker, means for actuating the awl independent of the means
from which the motion of the needle is derived, mechanism for revolving the
loop-taker in one and the same direction, and means for drawing the loop therefrom
and closing up the same before taking another loop from the needle.
6. The combination, in a wax-thread sewing machine, of a circularly curved.
needle and awl, a rotary shuttle or loop-taker, means for reciprocating the needle
and awl independently, mechanism adapted for rotating the shuttle with a
varying speed in one and the same direction, and means of advancing or feeding
the work.
7. The combination, in a wax-thread sewing machine, of a circularly curved
needle, a circularly curved awl, a rotary shuttle or loop-taker, means for
reciprocating the needle and awl independently, mechanism for rotating the shuttle
with a varying speed in one and the same direction, and means of drawing up and
finishing each stitch before another stitch is begun.
8. The combination in a wax-thread sewing machine, of a rotary shuttle or loop-
taker, and means for imparting a variable rotary motion thereto in one and the
same direction, of the circularly curved needle, the segmental needle-carrier,
the circularly curved awl, the awl-segment, separate levers and cams for working
the awl and the needle, and a thread-lever for drawing up and finishing the
stitch.
9. The combination in a wax-thread sewing machine of a needle, a rotary
shuttle or loop-taker, a puncturing awl, mechanism for separately operating the
needle and awl, an independent thread-case in the shuttle, and means of holding
the thread-case to prevent the same from revolving with the shuttle.
10. The combination of a circularly curved needle and awl arranged to enter
the work from opposite sides thereof, mechanism for separately operating the
needle and the awl, a rotary shuttle or loop-taker, means for imparting a rotary
motion to the shuttle, an independent thread-case in the shuttle, a stop on the
thread-case, and removable means of holding the thread-case from revolving
without interfering with the movements of the needle and awl.
11. The combination in a wax-thread sewing machine, of a circularly curved
needle, a rotary shuttle or loop-taker, a puncturing awl moving in line with the
needle, an independent thread-case in the shuttle, and a leader thereon for
delivering the shuttle thread to the work above and clear of the shuttle's point
while holding such thread out of the way of the needle and awl.
12. The combination of a rotary shuttle, a non-rotating thread-case therein, a
puncturing and feeding awl, a reciprocating needle, means for separately operating
the needle and awl, mechanism imparting an intermittent accelerative rotary

page_text: motion to the shuttle, and a thread-lever for delivering the needle thread to
the shuttle and drawing back the loop to finish the stitch in advance of the
operation of the awl.
13. The combination of a needle and a needle-carrier operated from the main-
shaft, a rotary shuttle and shuttle driver rotating in a vertical plane and
co-operating with the needle, a separate shaft variably rotated from the main-
shaft, a short shaft carrying the shuttle driver, a pinion on this driver shaft,
the second shaft also carrying a pinion, and the latter engaging the pinion on
the driver shaft, thus imparting the variable rotary motion to the shuttle, the
combination being and operating substantially as set forth.
Dated this 8th day of January 1895.
ALLISON BROS.,
Agents for the Applicant.