Improvements in Sewing-machines.
Year: 1891

page_text: Date of Application, 29th Sept., 1891-Accepted, 21st Nov., 1891
COMPLETE SPECIFICATION.
Improvements in Sewing-machines.
I, JAMES TRIPP, of 64 East Eleventh Street, in the City, County and State of
New York, United States of America, Machinist, 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:--
The improvements relate to the feed mechanism to the shuttle and shuttle-
driving mechanism, and to the thread retaining mechanism, of a sewing machine.
The second named improvement relates particularly to that class of sewing
machines in which the needle thread loop is engaged by a hook on a rotating
shuttle and is carried around the shuttle, the shuttle being supported in a circular
race which is so arranged that the axis of rotation of the shuttle is eccentric with
respect to the axis of rotation of the shuttle driver, so that the shuttle will at pre-
determined points of its path of revolution separate from the part or parts of the
driver, that engages and rotates it to let the thread loop pass.
The first and third features of improvement are applicable to various forms of
machines.
In the accompanying drawings
Figure 1 is an elevation view of the head of a sewing machine, the base or work
plate and a part of the needle arm being in central vertical section, and the bobbin
case being removed from the shuttle.
Figure 2 is a view of the same on the planes a a of Figure 1, and looking from
the left hand end of the same.
Figure 3 is a front elevation view on an enlarged scale to that of Figures 1 and 2
of the shuttle race and adjacent parts, the bobbin case being shown in place, and
the shuttle and its driver being shown at the position of taking the needle thread,
and the same as in Figures 4 and 13.
Figure 4 is a side elevation of the same parts, the parts being in central vertical
section except the shuttle and shuttle-driver.
Figure 5 is a similar view, the shuttle race being in section, and the shuttle being
rotated nearly one-half way around, as also shown in Figures 7, 8, 9, 10.
Figure 6 is an elevation view of the parts of Figure 5 on plane bb of Figure 5
and looking from the right hand of Figure 5, the position of the parts being as in
Figures 3, 4, and 13.
Figure 7 is an edge elevation view of the shuttle from the left hand side of
Figure 8, the shuttle being in the position of between one-third and one-half
rotation the position being the same as seen in Figures 5, 8, 9, 10, and 11.
Figure 8 is a rear face view of the shuttle in same position.
Figure 9 is an edge view of the same from the right-hand side of Figure 8 and
from the left-hand side of Figure 10.
Figure 10 is a front face of the same.
Figure 11 is an edge and a face view of the shuttle driver.
Figure 12 is a plan view of the work plate or bed of the machine about the
needle, the needle plate being removed to show the thread retaining parts below,
and the shuttle race and shuttle which otherwise would show being also removed.
Figures 13-16 are front elevation views of the shuttle race and shuttle, the
bobbin case being removed, also the face plate that holds the shuttle in the race,
and the bobbin holder, and the shuttle being shown in different positions of
rotation, as will be hereinafter more fully referred to and explained.
Referring to the views in detail, 1 is the base or work plate of the machine, 2 is
the needle arm; and 3 is the standard supporting the same from the base plate;
4 is the driving shaft, and 5 its driving wheel; and 6 is the feed rock-shaft, and
[Price 8d.1

page_text: 7 the feed plate. These parts are of the usual construction, it being understood
that any suitable needle-actuating mechanism, thread take-up and other motions or
parts necessary, may be attached to the needle arm.
8 is a cam on the main shaft, 9 is a fork engaging this cam, and to this fork is
pivoted at 10 the upper end of the link 11. The lower end of this fork is pivoted
at 12 to the block 13, which block is perforated and interiorly threaded and engages
the screw shaft 14. This screw is mounted in bearings 15 in the standard 3 so as
to be capable of being turned but not have motion longitudinally, and at one end
the shaft is provided with the thumb nut 16. The rock shaft 6 is journalled in
lugs 17 projecting from the under face of the plate 1. On the rear end of this
shaft is the crank-arm 18 to which is pivoted the lower end of the link 11, and on
the front end of this shaft is the crank-arm 19 to which is pivoted the feed-plate 7,
all in the usual way.
It is to be understood that such a feed-plate has a rectangular motion in
practice, and that the mechanism here described is only for giving the horizontal
motions and regulating the amount of feed. Other mechanism not here shown
and of well known form, is employed to elevate and depress this plate at the proper
times.
The operation will now be plain. As the main shaft rotates, the fork is vibrated
on its pivotal support and thereby pushes and pulls the link which in turn
oscillates the feed rock-shaft and causes the feed-plate to reciprocate longitudinally.
When it is desired to alter the throw of the feed-plate, the screw shaft is
turned, causing the pivot of the fork to change its position as to the pivot at
the upper end of the link, thus changing the angular relation of the lower end of
the fork to the link, and correspondingly lessening or increasing the movement
imparted by the fork to the link and by the link to the rock shaft and feed plate.
By these means, the throw of the feed plate can be regulated to the greatest
required nicety, and at the same time quickly and through any desired range.
The kind of shuttle to which my improvements are particularly applicable
consists essentially of a circular hoop or band of metal extending through some-
thing more than half a circle, the median plane of which I shall call the plane
of the shuttle, and this circular hoop I shall consider as the peripheral or bearing
edge of the shuttle, as it is this part of the shuttle that runs or is held in the
circular shuttle race. This peripheral hoop usually has attached to it a dia-
metrically arranged back plate, which carries the pivot and constitutes the socket
of the bobbin case, and one end of the hoop is pointed to form the hook that
engages the needle thread loop.
It is desirable, with such a form of shuttle that, as the thread loop is carried
around it, the thread be deflected as little as possible from the form of a plain
loop, that is, that the thread be not kinked or suddenly bent, or forced around
projections in its normal path the path it would tend to take were it, when
carried freely around the shuttle not opposed by other parts than those on the
shuttle. And this will be obvious, because any such deflection of the loop produces
friction and limits the speed of the shuttle, as well as tends to the breaking of the
thread and the clogging of the parts.
So far as I am aware, all forms of shuttles of this kind heretofore used, have
been operated by a driver that engaged with the shuttle by parts that projected
from the driver to and through the shuttle to the front face of the peripheral hoop
of the same, or at least beyond the plane of the shuttle. With such con-
structions, the portion of the loop passing rearwardly of the shuttle must be
deflected abruptly from its natural path to pass over or around at least one of
the said projections on the driver.
I therefore construct a shuttle and its driver in such form that the loop will
have a free and unobstructed passage around the shuttle, corresponding practically
to the normal path of the loop.
Referring to Figure 3 and the following figures, 20 is the shuttle race, which
consists of a circular ring properly grooved in its front face for the reception of the

page_text: peripheral hoop or circular edge of the shuttle such groove being closed and the
shuttle held in place by the open face plate 21. This race is adjustably supported
by screws 22 on lugs 23 depending from the base plate. The shuttle is represented
by 24, and it consists essentially of the peripheral hoop or edge 24 provided at its
toe end 25 with a loop taking hook 26 and at its other end with the heel 27. This
hoop runs in the race, and by it alone the shuttle is held in the race. 28 is the
thread guard, which consists of a segmental bridge-like strip gradually rising
from the hoop 24, by the bevel 29, to a height about the same as the outer face of
the bobbin case, and it is this guard that expands and directs the outer portion of
the loop over the bobbin holder.
These parts are of the usual and well known construction and it is also to be
understood that the race is so set that the axis of rotation of the shuttle is eccentric
to the axis of the driver shaft, in order to effect a separation of the engaging parts
of the driver and shuttle at such positions and times as is required for the loop to
pass, and that the driver has a variable though continuous motion, in order to time
the shuttle to the motion of the needle and to the thread take-up mechanism.
At the rear face of the shuttle hoop and diametrically spanning it from side to
side, is the back bar 30, which is socketed to receive the bobbin case 31 being the
bobbin axis. This bar is bevelled off at each end, as seen at 32 and 33, down to
the hoop 24. In constructing the shuttle the position of this bar on the hook 24
may be somewhat varied depending upon the position the driving bearing 40 carried
thereon should have relative to the driving bearings 25 and 27, which position
should be such that any plane including one of these three bearings and the axial
line of the shuttle will pass between the other two bearings.
34 is the shuttle driver, which consists of a segmental disc-like head, borne on the
end of the shuttle shaft 34" journalled in the lug 54, and having three horns 35, 36
and 37 projecting forward from the same. The tops of the toe horn 35 and the
heel horn 36 are connected by the thread guard 38, and are of sufficient height
to project to and slightly beyond the plane of the shuttle, Figures 4 and 5, to
engage respectively the toe and heel of the shuttle and the distance between the
bearings of these horns is slightly less than the corresponding distance between the
heel and toe of the shuttle. "The horn 37 is shorter than the other horns, and is
located about midway between them Figure 11 and it projects only so far forward
as to engage by its bearing face 39 with the shoulder 40 formed by the edge of the
bevel 32 of the shuttle bar 30. The distance from the face 39 of this horn to the
horn 35 is slightly less than that between the face of the heel 27 of the shuttle and
the shoulder 40 on the back bar 30. To afford further an ample and normal
passage for the inner portion of the loop, to pass this horn 40 as the loop is being
expanded and to prevent the thread being deflected by the edge of the shuttle rim
or hoop, the inner face of the hoop is slightly cut away or concaved as seen at 41.
This concavity is not essential, as obviously the shuttle hoop may be made thinner,
but in many cases it is a desirable feature, especially when the shuttle hoop is made
comparatively thick and strong as shown in the drawings.
The operation of these parts will now be plain. As the thread is taken by the
shuttle hook Figures 3 4 and 13, the shortest horn 37 of the driver is driving the
shuttle by bearing on the back bar of the same. As this horn passes the plane of
eccentricity (the dotted line of Figure 13) the shuttle begins to separate from it,
and the horn 36 begins to engage the heel of the shuttle, so that as the shortest
horn approaches the loop, Figure 14, it is well separated from the shuttle and the
loop falls naturally into the concavity 41 (see Figure 5) under this horn and
between this horn and its bearing 40, and begins to be expanded, to pass the
bobbin case, by the bevels 29 and 32 on the thread guard and the back bar of the
shuttle.
The further movement of the shuttle, to the position of 180° (Figure 15) brings
the short horn 37 of the driver into contact with the shuttle begins to relieve the
heel horn 36 from contact therewith, and opens a space between the toe of the
shuttle and the toe horn 35 of the driver, so that the loop slackens by moving

page_text: along the bevel of the toe of the shuttle and is free to cast off. The further move-
ment of the shuttle through the second 180° completely frees the long horn 36 of
the driver from the shuttle, and leaves a free space between the thread guards of
the driver and shuttle for the loop to pass as it is taken up, see Figure 16.
By these means, it will be seen that the loop has a full and direct passage around
the shuttle; at no point is it abruptly deflected, bent or doubled; during its entire
passage it
preserves a normal form see the position of the loop in Figures 5, 8, 14
and 15. This permits running the machine at a higher speed than is common with
other forms of machines having similar forms of shuttles, and obviates cutting and
punching the thread. This is largely due to the construction of the shortest driver
horn, and its arrangement to engage the shuttle back of the plane of the same.
It is also to be noticed that the cast off takes place at 180° a thing not possible
with other similarly operated shuttles, and the essential advantage thus secured is
that the thread take-up mechanism can operate through a longer period and hence
have a smoother action with less friction resulting also in simpler parts for the
take-up devices. Again, the thread is taken up through 180° of the revolution and.
smoothly and regularly, being not jerked or twitched and this also permits higher
speed than in machines where the take up is effected through a smaller arc, and this
long take-up motion is due to the fact, that putting one of the driving horns behind
the plane of the shuttle permits the arrangement of the shuttle hook close to the
shuttle toe; in fact the hook and inner end of the toe are so nearly on the same radial
line that just before the hook passes 180° the slack of the thread is effected,
followed immediately by the beginning of the take-up action. It will also be seen
in this connection, that the variable character of the speed of the driver can be.
less than is commonly the case, which, again adds to the possibilities of high speed
of the machine, and reduction in wear and friction.
The form of the shortest driver horn and its relation to the shuttle may be
modified, but it is essential that it engage the shuttle back of the plane of the rim
of the same or back of the bearing points of its other horn or horns.
It is to be understood that the toe horn is not for driving the shuttle forwardly
it serves a function common to such devices, of driving the shuttle when the
driver revolves backwardly, and is not a feature of novelty here.
Referring to Figures 234, 42 indicates a finger lever that holds the bobbin in,
position in the shuttle. This lever is pivoted by a screw at 43 to the front of the
shuttle race, and behind it and fixed to the race by the screws 43 and 44 is a bar 45.
that is notched at 46 to receive a projection 47 on the bobbin case. 48 is a spring!
piece cut from the material of the bar 45 and is bent forward over the lever 42 and
bears upon the cam point 49 of the same, which point is slightly to the right hand
side of the pivot of the lever.
To remove the bobbin the free end of the lever is forced down, as shown in full
lines in Figure 2 and in dotted lines in Figure 3 thus uncovering the bobbin case,
which can be then readily removed. The spring acts upon the cam of the lever to
hold it in either the open or the closed position, and particularly does it serve to
ensure the proper return to place of the lever after the bobbin has been put in the
shuttle.
The third feature of improvement relates to thread retaining mechanism, that is,
to mechanism whereby the needle thread is seized and held at the time the loop is
being formed by passing over the shuttle, and then is freed, the particular function
of this mechanism being to hold the loose end of the needle thread at the time
sewing is begun. This feature consists of means whereby the needle thread is at
the desired intervals siezed and retained between two pieces or jaws one of which
jaws has a vibrating motion relative to the other jaw, and is arranged and operated
so that its thread engaging edge reciprocates across the path of the needle thread
and also across the thread engaging edge of the other.jaw.
50 is the fixed jaw. It consists of a narrow plate of thin metal secured in proper,
position at each end, and on opposite sides of the needle 51, to the bed plate 1.
This plate is pierced by the needle hole or slot 52. 53 is a rocking arm pivotally

page_text: mounted on the shuttle shaft bracket 54, and is slotted to receive the eccentric
cam 55 on the shuttle shaft 34". From the upper end of the arm projects forward,
and across the upper face of the plate 50 to the needle, the movable thread-retaining
jaw 56. This jaw is rounded off at its end next the needle and preferably it is
slightly hooked; it is also sufficiently elastic to properly hold and to yield to
threads of different thicknesses.
It will now be seen, that as the shuttle shaft rotates, the edge of the movable
thread-retaining jaw is reciprocated across the slot in the other jaw or plate. The
parts are so timed to the shuttle, that after the needle reaches the end of its down-
ward excursion and has commenced to rise the movable jaw comes into contact
with and forces the needle thread between its lower flat face and the upper face of
the fixed jaw plate, whereby the thread is held until the loop has passed about one-
half way around the shuttle. Thus, at the beginning of the sewing, the free end
of the thread is retained long enough to be secured by the shuttle thread, and it is
not required to hold it by hand..
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is :-
First. The combination in the feed mechanism of a sewing machine, the feed
plate 7, the rock-shaft 6 having crank arms 19 and 18 pivotally attached respectively
to the feed bar and to the lower end of the link 11, the main shaft 4 and the cam 8
and a fork 9 engaging said cam and having a laterally moving pivotal support 13
and being pivoted to the upper end of the said link above its said support.
Second. The combination, in the feed mechanism of a sewing machine, the
feed plate 7, the rock-shaft 6 having crank arms 19 and 18 pivotally attached
respectively to the feed bar and to the lower end of the link 11, the main shaft 4
and cam 8 thereon, and a fork 9 engaging said cam and givotally supported at its
lower end on the block 13 and being pivoted to the upper end of the link 11 at a
point above its pivotal support, and a screw 14 supported in the standard 3 and
engaging said block and adapted to move it to and from the said link.
Third. The combination in a sewing machine shuttle-operating mechanism of
a shuttle race a rotating shuttle supported and running therein by a peripheral
hoop 24 and having a driving bearing 27 located in the plane of the said hoop and a
second driving bearing 40 located back of the plane of the hoop, and a rotating
shuttle driver arranged with its axis of rotation eccentric to the axis of rotation of
the shuttle and having the horn 36 extending forward to the plane of the shuttle to
engage the bearing 27 and a horn 37 projecting forward to back of the said plane to
engage the bearing 40, substantially as and for the purpose set forth.
Fourth. The combination of the shuttle, the shuttle race and the shuttle driver
arranged with its axis eccentric with respect to the axis of the shuttle, as and for
the purpose set forth; the shuttle being provided with a peripheral hoop rim 24
having in the same plane the heel bearing 27 and a toe 25 and hook, 26, and with the
back bar 30 having the bearing 40; and the driver being provided with the horn 36
projecting to and adapted to engage said bearing 27 of the shuttle with the horn 37
projecting to and adapted to engage the bearing 40, and with the horn 35 engaging
the toe 25, substantially as and for the purpose set forth.
Fifth. In combination with a rotating shuttle and its race, the bar 45 secured to
the race at each end and upon opposite sides of the bobbin case and having the
notch 46 and spring 48 formed therein, the lever 42 pivoted on said bar and having
the cam 49 upon which said spring presses and the bobbin case located behind the
said lever and provided with the projection 47 entering the said notch substantially
as and for the purpose set forth.
Sixth. The combination in a sewing machine of thread retaining jaws arranged
one above the other and located close to the needle path, one of the jaws being
vibrated relatively to the other with its thread engaging edge reciprocating across
the path of the needle thread and the thread engaging edge of the other jaw, and

page_text: being operatively connected with the driving mechanism of the machine substantially
as and for the purpose set forth.
Seventh. The combination in a sewing machine, of the plate 50 having the
needle-hole 52, the thread-retaining jaw 56 arranged and operated to reciprocate
across the needle hole and the thread engaging edge of said plate, the vibrating 6
arm 53 carrying said jaw and the shuttle-shaft 34" and cam 55 thereon for operating
said arm substantially as and for the purpose set forth.
Dated this 29th day of September 1891
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.