Improvements in Sewing Machines.
Year: 1898

page_text: Date of Application, 12th July, 1898-Accepted, 23rd Dec., 1898
r
COMPLETE SPECIFICATION.
Improvements in Sewing Machines.
I, FRANCIS HENRY RICHARDS, of No. 13, Murray Street, in the City, County,
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 per-
formed, to be particularly described and ascertained in and by the following
statement:-
-
This invention relates to sewing-machines and more particularly to combined
lock-stitch and chain-stitch machines in which the stitch-making mechanism
includes a reciprocatory needle, a rotary looper, and means for actuating the
needle and looper in proper timing one relatively to the other, and in which the
looper of the needle-thread may be engaged by and carried around the looper
end to inclose a second or lower thread to form a lock-stitch, or in which said
loop may be carried through a preceding loop to form a chain-stitch; and my
invention relates more particularly to the looper mechanism, which includes the
looper and driver, and to means for effecting a change in the form of stitch being
made without the necessity of reversing the direction of movement of the looper,
feed mechanism, and other parts of the machine, and to means whereby the
tension of the upper thread may be varied predetermined definite amounts con
currently with changes in the forms or characters of the stitches.
In order to secure the best results on stitching with a mechanism embodying a
reciprocatory needle and a rotary looper having a plurality of loop-takers or
hooks adapted for carrying successive loops at the same time, each preceding loop
should be fully drawn up and tightened, and each succeeding loop; which is
developed mostly from said preceding loop, must be fully drawn out after the
needle is withdrawn and before it re-enters the fabric. Furthermore, it is advan-
tageous that each preceding loop shall be fully drawn up and tightened by the
hook carrying the succeeding loop before said hook begins to draw thread from
the spool to complete said succeeding loop irrespective of the kind of stitch being
made.
It is a well-known fact that in stitch-making mechanisms of this character
a greater amount of thread is required and utilized from each preceding loop to
make a chain-stitch than is required to make a lock-stitch, less thread being
drawn from the preceding loops during the travel of the looper through successive
predetermined arc-distances in developing successive chain-stitches than is
required in developing successive lock-stitch loops; therefore it will be seen that
when a chain-stitch is being made by stitch mechanism of this class embodying
a rotary looper having a plurality of hooks or loop-takers there is less thread
remaining in a preceding and succeeding loop to reach from their respective
carriers to the fabric than there is when a lock-stitch is being made, owing to the
difference in the amount of thread utilized in the formation of the different
stitches, and for this reason it has been an impossibility in stitch mechanisms
heretofore known to make in a proper way, a chain-stitch and a lock-stitch without
employing a rotary looper of special construction for every kind of stitch being
made or without employing a looper having two independent sets of hooks-to

page_text: wit, one set of chain-stitch hooks and one set of lock-stitch hooks-so disposed
that the distance between adjacent loop-holding portions of adjacent loop-carriers
of the lock-stitch set will be greater than that between corresponding portions of
the adjacent carriers of the chain-stitch set, this difference in distance being
intended to compensate for the difference in length of thread contained in the
two loops extending from the adjacent hooks to the fabric, one loop of which is
being drawn by the other loop and each other loop is being drawn out.
One object of this invention is to furnish a stitch-making mechanism embody-
ing a rotary looper having one set of loop-takers or hooks constructed for move-
ment toward and away from the other whereby the distance between loop-holding
portions of adjacent hooks will be automatically varied by the movements of the
hooks caused by the tension of the loops, thereby compensating for differences
in the amount of thread utilized in making different kinds of stitches and
obviating the necessity of using two kinds of loopers or one looper having two
differently-spaced sets of hooks for the different kinds of stitches.
I..
A further object of the invention is to provide, in a stitch-making mechanism,
a rotary looper having, in addition to the loop-taker proper, a yieldable tension
device for engaging the loop of the needle-thread and for holding the same
under tension throughout a predetermined stitch-making operation, whereby to
take up unnecessary slack in the loop and obviate the injurious twisting or
kinking of the bight end of the preceding loop as said loop is being drawn up
by the succeeding loop, which kinking has been due to the slack condition of
the preceding loop and to the friction between the drawing side of said loop and
"the fabric as said loop is drawn through said fabric, which friction tends to rub
out or unwind the twist of the fibres of the thread at a point contiguous to said
fabric and force them backward, causing them to wind more tightly toward the
bight end of the loop and causing said loop to kink.
1.
:
In machines of this class as heretofore constructed and organized where the
looper is set to rotate at an angle oblique to the path of movement of the needle
and looper-driver and had a series of driver-sockets formed in one face thereof
to be entered by a series of pins on the looper-driver, it has been found in
practice that, owing to the relatively oblique angles of movements of, and the
resultant rolling action between, the looper and driver it was necessary, for the
purpose of facilitating the free movement of the driver-pins when engaging and
disengaging the looper, to form the driver-sockets of the looper of considerably
greater area than the driver-pins, and for this reason it was impossible to secure
such a co-operative engagement between the driver-pins and walls of the looper-
sockets as would enable the driver. to positively support the looper and obviate
wholly diametrical vibratory movement of said looper relative to the driver, as
is understood by those familiar with this class of looper mechanism.
:
A, further object of the invention is to provide an improved looper mechanism
in which the looper and driver are so constructed that they will co-operate in
a manner similar to that of two intermeshing gears, and in which the engaging
portion of the looper and driver are so constructed that said driver will positively
support the looper in fixed peripheral relation to the axis of the driver and wholly
obviate vibratory movement of such looper relative to said driver; and also-to
provide as an element of the looper mechanism means whereby the looper will
be guided in its movements but held as against movement transversely of its
path of rotation and being left free, so far as the guiding means are concerned,
for diametrical movement with said driver.
A further object of the invention is to furnish a looper mechanism embodying
a looper having one or more peripheral loop-takers or hooks and also having in
one side face thereof a series of sockets or recesses the outer and inner end walls
of which are spherical and concentric to a common center, and a looper-driver
having a series of projections or driver-teeth the outer and inner faces of which
are spherical and correspond to and co-operate with the spherical walls of the
looper recesses or sockets for supporting said looper in fixed peripheral relation

page_text: to the axis of the driver and incidentally for rotating the same, the spherical
outer and inner end faces of the driver being also concentric to a common centre.
Furthermore in machines of this class no means have heretofore been provided,
so far as I am aware, whereby different kinds of stitches could be formed
without changing the direction of movement or mode of operation of one or more
of the parts of the sewing-machine mechanism, or without removing the lock-
stitch-forming looper or shuttle and substituting therefor a looper or equivalent
device embodying means whereby a different manipulation of the loops could
be effected.
:.
A further object of the invention is to provide, in connection with the fabric-
holding and fabric-feeding devices of the sewing-machine, a differential stitch-
forming mechanism embodying instrumentalities normally operative for forming
a lock-stitch, and also embodying a stitch-changing device shiftable into position
to engage successive loops and so act thereon as to effect a change in the form
of stitch made or, in other words, to provide improved stitch-forming mechanism
embodying a reciprocatory needle and a rotary looper operating normally to form
a lock-stitch, and a stitch-changing device shiftable independently of the looper
into, such operative relation with said looper as to so manipulate the successive
loops as to compel each succeeding loop to pass through a preceding loop and
thereby cause the stitch-making mechanism to form a chain-stitch.
A further object of the invention is to provide, in connection with the stitch-
changing device, a needle-thread-tension device and means operative with the
stitch-changing device for varying the effective resistance of said tension device
upon the thread in accordance with the requirements as determined by the form
of stitch being made and by the movements of the stitch-changing device..
In the drawings accompanying and forming part of this specification, Figure 1
is a front elevation, partially in section, of one form of sewing-machine embody-
ing my improvements. Fig. 2 is an enlarged end view, partially in section, of
a portion of the lower part of the sewing-machine head as seen from the left
in Fig. 1. Fig. 3 is an enlarged sectional view of the needle-thread-tension device
and a portion of its actuating means. Fig. 4 is a vertical sectional view of the
looper, looper-guide, looper-driver. and a portion of the framework of the machine:
Fig. 5 is an enlarged side view of the looper detached, showing the driver-
sockets, therein. Fig. 6 is an enlarged end view of the driver for said looper.
Fig. 7 is a horizontal section of a portion of the lower part of the machine, taken
on planes corresponding with the dotted line bb, Fig. 1, a portion of the
bed-plate and feed-lever being broken away, illustrating the stitch-changing
device and the cam for operating said device, the looper and driver not being
shown. Fig. 8 is a longitudinal section, on an enlarged scale, of a portion of the
looper and driver, illustrating by radial lines the pitch-cones or angles of the
teeth of said driver and sockets of said looper. Fig. 9 is a diagrammatic view
of a portion of the looper-driver, illustrating the spherical curvature of the inner
and outer end faces and the angles of the front faces of the teeth of said driver.
Figs. 10 and 11 are enlarged side views, partially in section, of a portion of a
stitch-making mechanism detached-to wit, the looper, a portion of the throat-
plate, a portion of the stitch-changing device, and a piece of fabric, said figure
showing, respectively, two loops in corresponding positions and indicating: by
dotted radial lines the difference in position of the loop-carrying portions and
the difference in distance between the adjacent hooks of the looper during the
formation of a chain-stitch and a chain-lock stitch, Fig. 10 showing the position
of the loop-carrying portions of two adjacent hooks when a chain-stitch is being
made, and Fig. 11 showing the positions thereof when a lock-stitch is being made.
Fig. 12 is a side view, to an exaggerated scale, of a portion of a looper shown in
Fig. 11. Fig. 13 is a cross-section taken on the dotted line c-c, Fig. 12, looking
in the direction of the arrow in said figure. Fig. 14 is a plan view, partially in
section, of the loop-diverting end of the stitch-changing device, showing the
loop-diverter in full and dotted lines in four different positions, and also showing

page_text: a portion of the feed mechanism in dotted lines, Figs. 15, 16, 17, 18, 19, and 20
are perspective views of portions of the stitch making mechanism, showing the
looper, needle, and the loop-diverter of the stitch-changing device in six different
successive positions during one cycle of operation of the stitch-making mechanism
or during one stitch-forming operation.
Similar characters designate like parts in all the figures of the drawings.
Al
The sewing-machine illustrated in the accompanying drawings comprises in
a part a framework, a sewing-machine head (designated in a general way by F,)
which may be of any suitable construction for carrying the several parts;
vertically-reciprocatory needle-bar N¹, carrying the needle N; a needle-bar-
actuating shaft D, journaled in suitable bearings in the framework and having
a crank-and-link connection with the needle-bar; a rotary looper or shuttle S,
supported below and preferably at an inclination to the path of the needle-bar
and having a set of loop-carriers, which preferably include a loop-taker and a
loop-deliverer a looper-guide G, supported by a bracket G¹, depending from the
bed-plate of the machine and extending around the lower portion of the looper;
a looper-supporting driver H; a horizontally-disposed driver-actuating shaft D';
an intermediate shaft 12; a one-to-one train of gears E, connecting the inter-
mediate shaft 12 and the needle-bar-actuating shaft D; a two-to-three train of
gears E, connecting the shaft D2 and the driver-actuating shaft D'; feed
mechanism including a feed-lever 51, supported for universal movement and
having a feed-dog at the working end thereof, and a feed-lever-actuating cam 54,
fixed to the intermediate shaft D2 and adapted for actuating the feed-lever; a
stitch-changing device (designated in a general way by W) shiftable into operative
relation with the looper and adapted for deflecting preceding loops laterally of
the path of the needle in such manner that succeeding loops will be carried by the
looper through preceding loops to form a chain-stitch; a throw-out device
(designated in a general way by K) in operative connection with and effective
for shifting the stitch-changing device into and out of operative relation with
the looper;
a needle-thread tension device (designated in a general way
by M); and a tension-device actuator (designated by M¹) in opera-
tive connection with the throw-out device and effective on different move-
ments of said throw-out device for operating the tension device in such manner
as to vary the resistance or effective tension according to the kind, of stitch
being made.
The framework of the machine is shown consisting of a horizontal bed-plate 2,
having a throat-plate or cloth-plate 3: a depending looper-guide-supporting
bracket G at the work-supporting end of said plate; a hollow upright 4 at the
opposite end of the bed-plate; a horizontal overhanging arm 5 above said bed-
plate and a vertical needle-bar-receiving head 6 at the outer end of said arm.
The needle-bar N and presser P are shown axially coincident, the presser-bar
being tubular and the needle-bar being supported for reciprocatory movements in
said presser-bar, which presser-bar is in turn supported for vertical movements
in the head 6 and is furnished at the lower end thereof with a presser-foot 40,
a resistance-spring 41 and an adjusting device 42 being provided at the upper
end of the presser-bar for regulating the pressure of the presser-foot upon the
fabric.
The fabric-feed mechanism, which may be in practice of any suitable construc-
tion and organization, is shown in the accompanying drawings comprising a feed-
lever 51, supported substantially midway its length for universal movement and
having one end thereof bifurcated, as shown in dotted lines at 59, Fig. 7, to
straddle the actuating-cam 54, and also having at the opposite end thereof a feed-
dog 50, extending through the throat-plate 3 of the machine; and a feed-lever-
actuating cam 54¹, fixed to the intermediate shaft 12 and having a working
surface acting against the bifurcated end 59 of said feed-lever and constructed
and positioned to impart feed movements to the feed-dog in proper relation to
the movements of the needle and looper mechanisms.

page_text: The looper or shuttle S, which may be of any suitable general conformation,
is shown of the "discoidal" type and is supported below the throat-plate of the
machine for rotative movement in a plane oblique to the path of the needle,
(see Fig. 1,) said looper being guided in, and held against movement transversely
of the path of, its rotation by the parti-circular looper-guide G, which extends
around the lower portion, and has a raceway for receiving the perimeter of said
looper, and which raceway will in practice be of sufficient depth and be so set
with relation to the looper as to permit an unobstructed movement of the loop-
taker or hooks of the looper, certain of which are shown having their points
projecting somewhat beyond the perimeter of said looper and also permitting a
slight diametrical movement of the looper with the driver.
To facilitate the formation of lock-stitches the looper will in practice be usually
furnished with some suitable means (not shown)--such as a cob or bobbin-
carrier for carrying the lower thread, and also be provided with some suitable
tension device (not shown) for regulating the tension of said lower thread.
In the form thereof illustrated in the accompanying drawings the looper or
shuttle has one set of what may be consistently termed "combined lock-stitch
and chain-stitch carriers" (shown as three in number and designated in a
general way by h, h¹, and h², respectively,) and each of which is shown circum-
ferentially disposed and comprises two opposing preferably overlapping hooks 8
and 9, Fig. 5, supported at their bases by a loop-receiving recess 10. One of
these hooks, as 8, owing to its function, may herein be termed the "loop-taker,"
and the other opposing hook 9, owing to its function may be herein termed the
"loop-deliverer," although in a generic sense both the loop-taker and the loop-
deliverer may be termed singly and without choice the "loop-taker" or "hook,"
for the reason that both hooks.8 and 9 take the loop at successive different points
in the orbital movement of the carrier.
The looper or shuttle has formed in one side face thereof a series of driver-
sockets 12, the opposing outer and inner walls 13 and 131 of which are spherical
and preferably concentric to a common center, and the side walls 14 and 14'
of which are radial to said common center, as indicated by full and dotted lines
in Figs. 5 and 8 of the drawings.
For convenience the looper is shown having in the side face thereof three sets
of driver-sockets disposed relatively equidistantly about the axis of the looper and
each set embodying two sockets, as illustrated most clearly in Fig. 5.
As a means for supporting the looper free of diametrical support by the looper-
guide G, and for rotating said looper, a combined looper-carrier and driver H is
provided, which is shown consisting of a hub 15, fixed to a driver-actuating
shaft D and having preferably three radially disposed arms each having at the
outer end thereof preferably two teeth or driving-projections, (each of which is
designated by 15¹) said teeth being complemental to and adapted for entering
the sockets 12 in the looper, the inner and outer end walls of said teeth being
spherical and preferably concentric to a common center, and which spherical walls
.co-operate with the end walls of the looper-sockets for supporting said looper.
The projections 151 of the driver are shown in the nature of theoretically-
correct bevel gear-teeth having their outer and inner end faces 16 and 161
respectively spherical and concentric to the common center 75, the curvature of
the outer face of said teeth being indicated by the intersecting dotted lines op,
respectively, Fig. 9; and the angles of the side faces of said gear-teeth, which are
indicated by the dotted radial lines m-m', Fig. 9, coinciding with the angles of
the opposing side faces of the driver-sockets of the looper, which angles are repre-
sented by the dotted radial lines n'n' in said Fig. 8, all of said angles having
a common apex at 75.
Owing to the relatively-oblique disposition of the looper and driver it will be
seen that portions of the looper during the rotation thereof move successively
toward and away from the teeth of the driver, and that successive sets of pro-
jections or driver-teeth are älternately brought into and out of engagement with

page_text: the sockets of said looper, said driver-teeth being out of engagement with the
walls of the sockets' as they enter the latter, owing to the taper of the side faces
of the driver-teeth.
Further, it will be seen that the looper and driver co-operate in a manner
similar to that of two intermeshing bevel-gears; therefore to secure such proper
working engagement between the driver and looper that the driver-teeth will
freely enter the socket of said looper and at the same time have a close operative
engagement with the walls thereof, it is expedient to furnish the projections of
the driver and the socket-walls of the looper with co-operative faces of peculiar
construction, the peculiarity and novelty in the structure of the driver-teeth and
the walls of the looper-sockets residing in the spherical or peculiar curvilinear
conformation of the inner and outer end walls of said driver-teeth and the similar
tecth of the inner and outer end walls of said driver-sockets. Each inner and
outer end wall of each socket of the looper and each inner and outer end face of
each tooth of the driver is curved, as hereinbefore stated, in two relatively trans-
verse directions, the arc, as o, of one curve (see Fig. 9) being in the plane of
rotation of the looper, and the other arc, as 2, being transverse to said plane, and
both arcs being preferably concentric to the theoretical cone-center of the driver and
looper.
"
זו.'
From the foregoing it will be seen that both the looper and the driver have
corresponding driving-faces and corresponding looper-carrying bearing-faces. The
driving-faces of the looper are shown in the drawings as the side faces of the walls
of the sockets or recesses thereof, and the looper-carrying or bearing faces are
shown as the spherical end walls of said recesses, whereas the corresponding
driving-faces and looper-carrying faces of the driver are shown, respectively,
as the side faces and end faces of the teeth or projections of said driver. In the
drawings these faces are disposed in a circle about the axes of the looper and
driver, and it will be obvious that the disposition of these faces is an arbitrary
matter.
For the purpose of facilitating an unobstructed passage of the loop while being
carried around the looper in order to properly permit the same to be drawn out
in the usual manner, the front face 18 of the recessed portion of the looper and
the front face 19 of the projections or teeth of the looper are beveled or inclined
in substantial parallel line, clearance-spaces 20 being thereby formed between
the ends of the driver-teeth and adjacent upper end of the looper. By furnish-
ing the looper with sockets and the driver with teeth of the construction herein-
before described said parts will mesh with precision, and the outer and inner
ends of the driver-teeth will have a close bearing engagement with the outer
and inner end walls of the looper-sockets and will support said looper against
vibratory movement laterally of the looper-driver axis.
In the organization of stitch-making mechanism herein described the looper S
is indicated to rotate continuously in one direction-in the direction of the
arrow in Figs. 15 to 20, inclusive-the loop-takers 8 all pointing in the same
direction.
As shown in Fig. 4, and as indicated in dotted lines in Figs. 10 and 11, the
looper is circumferentially grooved, as at 171, at successive points adjacent to the
loop-carriers and at one side of the perimeter or track 181, each groove merging
in the loop-receiving recess 10 at one end and terminating at the opposite end
substantially midway between this recess and the next adjacent recess.
The hooks 8 and 9 of the looper have their adjacent points 8 and 9¹ disposed
preferably in overlapping relation, the loop-taking hook 8 having a point thereof
contiguous to the needle-groove and extending outward somewhat radially beyond
the outer face of the hook 9. This construction-to wit, the outward extension
of the hook 8-permits the looper to be supported so that the front of said hook
will, during the rotation of the looper, describe a path in close proximity to the
under side of the throat-plate, while the perimeter proper of the looper will be

page_text: located sufficiently below said plate as not to interfere with the loop-threads
during certain stages in the formation of the stitch.
The two hooks 8 and 9 as before stated, point in opposite directions and will
in practice have their adjacent side faces preferably in parallel planes to form a
diagonal passage-way between said faces leading to the loop-receiving recess 10,
thus permitting the hook 9 to carry a preceding loop sidewise during the drawing
up of said loop out of the path of the next succeeding loop-taker 8, which latter
being located at one side the path of the loop-deliverer carrying the preceding
loop serves to carry the succeeding loop free of the old loop and thus avoid
chafing, which might otherwise occur when a stitch is being made.
Furthermore, by constructing the loop-taking hook so that the point thereof
may travel in a path in close proximity to the end face of the throat-plate with-
out bringing the main portion of the perimeter of the looper into closer proximity
than heretofore necessary with this class of loopers the downstroke of the needle
may be lessened, thus requiring the drawing out of less thread in forming a loop
and consequently decreasing the amount of thread taken up.
I.
For the purpose of facilitating the proper drawing up of succeeding loops, and
for holding each succeeding loop under tension throughout a predetermined
portion of its movement around the looper, I have provided, in operative relation
with each loop-carrier, a loop-tensioning device, (designated in a general way
by T.)..which in the form thereof shown most clearly in Figs. 10, 11, 12, and 13
of the drawings, is in the nature of a spring-held or reactionary loop-engaging
finger pivotally supported at its inner end on the looper at a point below the loop-
holding portion of the loop-taker or hook 8 and projecting at its outer free end
into the loop-receiving recess 10, the outer face of said finger being preferably
disposed in substantial parallelism with the inner face of the loop-taker 8 when
said finger is in its loop-engaging position. Said finger intersects the path
transversely of the bight of the loop along the inclined wall 20 of the loop-
receiving recess, as will be understood by a comparison of Figs. 10, 11, and 15
to 20, inclusive.
The loop-tensioning device or reactionary-loop-engaging finger T is shown in
Figs. 12 and 13 pivotally supported in the recessed inner end of the plug 21,
which is secured in suitable bearings formed in the face of the looper, said plug
being held in place by a screw 22, which extends through the plug and one end
of the finger and has a screw-threaded bearing in said looper, the finger or loop-
tensioning device being pivotally supported on the shank of said screw and being
held in its normal loop-engaging position and under the requisite tension by a
spring 23, which is shown as a coiled spring fixed at one end in the plug and at
the opposite end in the tension device, as shown clearly in Fig. 13.
The loop-tensioning device T will in practice be limited in its movements in
opposite directions by..stop-abutments 24 and 24', which are shown in dotted lines
in Fig. 12 as the opposing walls of a transverse recess in the plug through which
the outer end of the tension device extends.
To provide a seat for the tension carrier or plug 21, the looper is bored trans-
versely from one side, which bore communicates with the loop-receiving recess 10
and cuts away a sufficient portion of the inclined wall of said recess to permit. the
requisite amount of the tension device when the plug and said tension device are
assembled, as shown in Fig. 13.
The reactionary loop-tensioning device T will be so disposed with relation to
the loop-holding portion of the loop-taking hook 8 as to receive the bight of the
loop, as set forth, immediately after said loop has arrived at its fully-drawn-out
or let-off position, or when the hook carrying said loop. has arrived at that position
in its traveling movement where the loop is released from the base or loop-
holding portion of the hook, and rides down the inclined wall of the loop-receiving
recess 10.
By providing a loop-tensioning device in co-operative relation with the loop-
taking hook of the looper the free end of which tension device is depressed

page_text: between the loop-taker and the inner wall or its portion of the loop-receiving
recess the loop-taking hook 8 will serve to engage the loop of the needle-thread
and carry the same around the looper to a predetermined definite position--to
wit, to a position where the loop will be fully drawn out--when the bight of the
loop will be released from the loop-holding portion of said hook and will travel.
along the inclined wall of the loop-receiving recess 10 until it is engaged by the
loop-tensioning device, the engagement by said device taking place when the
Hook carrying said loop has arrived substantially at the positions shown in Figs.
and 15 of the drawings, after which the loop-tensioning device will serve to hold
the opposite portions of said loop taut and under predetermined tension-taking
up the slack therein--until said hook, loop, and tensioning device arrive at the
positions illustrated in Fig. 17, when the bight of the loop will release itself
from the loop-tensioning device and will engage the inclined wall of the loop-
delivering hook 9.
The bight of the loop during the orbital movement of the hook 8 from the
position shown in Fig. 16 to that shown in Fig. 17 travels gradually along the
outer face of the loop-tensioning device from the inner to the extreme end thereof
until it is released from said tensioning device, which allows said device to return
to its normal position.
For the purpose of rendering the looper equally effective in the formation of a
lock-stitch and a chain-stitch without the necessity of providing and utilizing
specially constructed sets of hooks for different stitches, one hook, as 9, of which
loop-carrier is constructed and supported to have a movement toward and away
from the adjacent hook, as 8, said hook 9 being spring-held or reactionary and
being limited in its movements toward and away from the adjacent hook by some
suitable means as hereinafter described.
The loop-delivering hook 9 is shown in Fig. 12 having the outer face thereof
concentric to the axis of the looper, said hook being somewhat in the nature of
a plate pivotally supported at its inner end, as at 911, and has a recess formed in
the looper at one side the needle-groove, the thickness of the plate at the inner
pivoted end thereof being in practice sufficient to procure a proper bearing between
the opposing walls of the spaces in which the loop is located, and the outer
portion of said hook will preferably be of a thickness coinciding substantially
with the thickness of the peripheral track 18' of the looper, although the front
or loop-engaging end of the hook is beveled or inclined on the face of the adjacent
hook 8, as herein before described.
As a means for holding the loop-deliverer or hook 9 normally in the position
shown in Fig. 12 a spring 27 (shown in dotted lines in said figure) is preferably
provided, which has a bearing engagement at one end against the hook and at its
opposite end against the wall or recess in which said hook is located, said spring
being so disposed as normally to force said hook forward and toward and in
overlapping relation with the loop-taking hook 8, and means for loosening the
advancing and retractive movement of this hook, a movement-limiting device is
provided, which is shown in dotted lines in Fig. 12 as a pin 28, extending through
a portion of the looper and into a diametrically-enlarged recess formed in one side
of the hook, the opposing wall portions of the recess constituting stop-abutments
for determining the range of movement of said hook.
By providing stitch-making mechanism with a rotary looper having a series
of looper-carriers each embodying a movable reactionary loop-taker or hook the
distance between loop-holding portions of the hooks of adjacent carriers will be
varied by the stress of the thread during the drawing up of a succeeding loop and
in accordance with the necessary requirements, thus rendering the looper practi-
cally operative in the formation of different kinds of stitches in which different
amounts of threads are utilized from preceding loops in making said stitches.
Any number of adjacent loop-holding portions of the looper will be so disposed
with relation to each other as to render the looper normally operative for forming a

page_text: lock-stitch, the distance between these portions of the hooks being normally
greater than is actually required for the drawing-thread to reach from a pre-
ceding hook through the fabric and the next succeeding hook and the range of
movement of the movable hook will in practice be such as to allow a retractive
movement of said hook sufficient to facilitate the formation of a stitch in which
there will be less thread to reach from the loop-holding portion of one hook
through the fabric to the loop-holding portion of the next succeeding hook for
the formation of a chain-stitch than for a lock stitch, a greater amount of thread
being utilized from the preceding loop in forming a chain-stitch than from a
preceding loop in forming a lock-stitch.
As a convenient means for changing the form of stitch resulting from the
normal operation of the looper and needle mechanism-which mechanism will
be normally operative for making a lockstitch-without effecting a change in the
direction of movement of the looper or feed mechanism or in the mode of operation
of the several elements of the stitch-making mechanism a stitch-changing device
(designated in a general way by W) is provided, which stitch-changing device is
shiftable into position for co-operating with the loop-takers and is adapted for
engaging the upper portion of successive loops and for deflecting said portions
laterally of the path of the needle so that succeeding loops may pass through
preceding loops and cause the stitch-making mechanism to produce a chain-
stitch.
The construction and operation of the stitch-changing device is such that the
same may be thrown into and out of operative relation with the looper arbitrarily
to effect a change in the form of stitch made by the stitch mechanism without
the necessity of changing the direction of the looper, the direction of movement
of the feed mechanism, and without the removal and substitution of parts as
heretofore necessary in machines of ordinary construction.
It is desired to state in the above connection that this invention is not limited
to the particular construction and organization of stitch-changing device illus-
trated in the accompanying drawings as these may be variously modified within
the purview of this invention while adhering to the stitch-changing device which
is independent of the looper and is shiftable into a position for so co-operating
with said looper and for so manipulating successive loops as to effect a change in
the form of stitch which otherwise would be produced by the normal operation
of the stitch-making mechanism if such stitch-changing device were not provided.
The stitch-changing device W (see Figs. 1, 2, 7, 14, and 15 of the drawings)
comprises a loop-diverter 60 (shown as a lever) fulcrumed at 601 below the bed-
plate of the machine for horizontal oscillation across the path of the loops; an
actuating-lever 62, fulcrumed at 621 in close proximity to the intermediate
shaft D2 and connection 63 between the actuating-lever 62 and the loop-diverter 60,
which connection is shown as a rod pivotally connected at opposite ends to said
loop-diverter and actuating-lever, respectively, a cam 64, fixed to the intermediate
shaft D and having a working face in position to operate the actuating-lever 62;
a spring 65 for normally retaining the actuating-lever 62 in working engagement
with the cam 64: and a throw-out device in operative engagement with the
actuating-lever of the stitch-changing device, and effective for shifting the.
actuating-lever 62 of the stitch-changing device out of or into operative relation
with the operating-cam 64, and, incidentally, the loop-diverter 60 out of or into
operative relation with the looper S.
The stitch-changing device is shown in the drawings located in front of the
feed mechanism so that the loop-diverter 60 will engage the loop in advance of
the needle. This loop-diverter is shown furnished at one end thereof with a loop-
engaging portion or hook 60", which, during the operation of the stitch-changing
device, engages the upper portion of the inner strand of the loop and carries the
same sidewise and in advance of the path of the needle, as clearly illustrated in
Figs. 15 to 20, inclusive, of the drawings.

page_text: To secure the best results in the operation of the stitch-changing device it is
desirable that the loop-diverter shall be advanced to engage and deflect the upper
portion of the loop immediately after said loop has been carried to its fully drawn
out position, as shown in Fig. 15, and shall be in this position until the succeeding
loop has passed through the preceding loop and has carried the engaged portion
of said preceding loop forward and out of engagement with the hook 60 of
the loop-diverter, as shown most clearly in Fig. 19, and shall be retracted out
of the path of movement of the loop just before the preceding loop is retightened
by the drawing out of the succeeding loop-in other words, it is preferable that
the deflection of the upper portion of the loop shall take place during the travel
of the loop around the shuttle through its greatest slack position or when
sufficient slack thread exists in the loop proper to provide for such deflection
without the necessity of drawing off more thread from above the needle-point;
and as a convenient means for effecting this end the actuating-cam 64 has a
quick-acting portion 64 and is so disposed upon an intermediate shaft that is
connected to the looper-driver-actuating shaft, and is so timed with reference to
the movements of the looper that it will advance the stitch-changing device to
its loop diverting position and will retract said device to an ineffective position
at predetermined points in the rotation of the looper.
It will be obvious that other instrumentalities than those illustrated in the
drawings may be provided for actuating the loop-diverter, and therefore the
invention is not limited to the particular construction and organization of
actuating means shown.
The throw-out device preferably consists of a stud 66, supported for rotative
movement in a bearing 67 in parallelism with an intermediate shaft D3 and
having a crank-arm 68 at the lower end thereof, on which the actuating-lever 62 is
fulcrumed, said stud and crank-arm being adjustable rotatively to throw the
fulcrum-point of said lever 62 toward and away from the axis of the cam 64
to bring the working end of said lever into engagement or out of operative
relation with the working face of said cam, and said stud is also supported to
have a movement in a vertical direction concurrently with its rotation and con-
stitutes in the organization shown an actuator for the adjusting device that
regulates the tension of the needle-thread, as hereinbefore described.
For operating the stud to rotate and lift the same a thumbpiece is provided,
which is shown as a set-screw 70, extending through an inclined slot 71, formed
through one wall of the bearing 67 and having the inner end of its shank screwed
into the stud 66, as shown most clearly in Fig. 7. The shape of the slot and the
end walls of the same determine the extent of vertical and rotative movements,
respectively, of the stud 60.
When it is desired to throw the stitch-changing device into the inoperative
position to allow the stitch-making mechanism to form a lock-stitch, the thumb-
piece 70 is shifted toward the upper end of the slot 71, which throws the actuating-
lever 62 with its working end out of operative relation with the working face of
the actuating-cam 64 and simultaneously elevates the stud 62 to operate the
needle-thread-tensioning device M, as hereinbefore described, the retracting-
spring 65 throwing the loop-diverter 60 to an inoperative position with relation
to the looper, as shown in Fig. 20.
When it is desired to cause the stitch-making mechanism to produce a chain-
stitch, the chain-stitching device will be shifted by means of the throw-out
device in opposite direction to that above described and into operative relation
with the cam 64, the stud 66 of said throw-out device being lowered to effect an
increase in the tension of the needle thread.
On the engagement of the upper portion of the loop by the hooked end of the
loop-diverter said portion will be carried sidewise slightly in the path of the
needle to allow said needle to enter the looper in the rear of the deflected portion
of said loop, so that on the engagement of the succeeding loop by the loop-taker

page_text: the deflected portion of the preceding loop will be in position to allow the bight
of the succeeding loop to pass through said succeeding loop and thereby cause
the stitch-making mechanism to form a chain-stitch, the hook of the loop diverter
positively holding the deflected portion of the loop in its position until the
succeeding loop passes through the preceding loop and forces the deflected portion
of the preceding loop forward and out of engagement with the hook of the loop-
diverter, thereby preventing the release of the deflected portion of the loop until
after the succeeding loop has passed through the same.
It will be understood that when a chain-stitch is made the lower thread
normally carried by the looper will be dispensed with, and that when it is desired
to form a lock-stitch or a lock-chain stitch the end of the lower thread will be
drawn up through the throat-plate in the usual manner.
In the operation of stitching either when a lock-stitch or a chain-stitch is being
made the looper is preferably rotated constantly in the direction of the arrow in
Fig. 15, and the hook S will first engage the loop and carry the same around
said looper until said loop is fully drawn out when the bight of the loop will
slide down the inclined wall and engage the loop-tensioning device and hold the
same under tension until the looper arrives at a predetermined position where it
is to be released from the loop-tensioning device, after which it engages the inner
wall of the delivery-hook 9, which still retains said hook under tension during
the drawing up thereof and until said loop is released from the end of this hook,
after which it will be drawn up tightly against the fabric by the drawing out of
the next succeeding loop, as will be understood by a comparison of Figs. 15 to 20
of the drawings.
In stitch-making mechanisms embodying rotary loopers no means, to my know-
ledge, have been heretofore provided for engaging the loop of the needle-thread
and for holding the same under tension throughout a portion of the stitch-forming
operation, and more particularly throughout that portion of the stitch-making
operation where the preceding loop is drawn up by a succeeding loop, and in con-
sequence much difficulty has been experienced by the twisting or kinking of the
bight end of the loop as the same is being drawn up in proximity to the under
side of the fabric, which kinking precludes the possibility of drawing the bight
of the loop tightly against the under side of said fabric, owing to the knotty
condition of that portion of the thread drawn through the fabric, which naturally
obstructs the full drawing up of the bight of said loop, leaving usually a knotty
or twisted portion of the loop projecting below the fabric, which if not long
enough to be caught and broken by the succeeding loop-takers of the looper or
entangled in and broken by the succeeding loops it is sufficient to produce an
imperfect and an undesirable stitch.
•
It has been demonstrated by practical experiments that the objectionable
kinking or twisting of the opposite portions of the bight end of the loop is in
the greatest measure due to the slack condition of said loop during the period of
its travel around the looper where it is being drawn up by the next succeeding
loop, for the reason that the strands of the loop, owing to the slack condition.
exert no resistance to counteract the natural twisting action exerted upon the
running thread of the loop as the same is being drawn through the fabric, the
friction between these strands and fabric tending to rub out the twist of said
strands at a point contiguous to the fabric and force the coils thereof backward
toward the bight end of the loop, consequently consolidating or shortening the
spirals of the twist, which results in an augmented winding of said fibers and
causes the two opposite portions of the bight end of the loop to twist around each
other immediately upon the release of the bight from the loop-delivering hook.
This detrimental twisting and kinking of the bight end of the loop is positively
prevented by the improved means herein described, which holds the loop under
tension during the drawing up thereof.
In sewing-machines of this class--that is, change-stitch sewing-machines--it

page_text: is desirable and also a mater of extreme importance that the tension upon the
needle-thread shall be varied in accordance with the requirements as determined
by the kind of stitch being made, owing to the different amount of thread utilized
in making different kinds of stitches. For the purpose of securing automatically
a variation in the tension of the upper thread as required when different kinds
of stitches are being made by the stitch-making mechanism I have provided an
adjustable needle-thread-tensioning device M, and I have also provided in con-
nection with said tensioning needle-thread device a tension-regulating device 0,
operatively connecting the tension device and an element of the stitch-changing
device W and effective on the shifting of the stitch-changing device into operative
relation with the looper--as, when a chain-stitch is being made-for decreasing
the resistance of the tension device upon the upper thread to a definite extent,
and effective on the shifting of the stitch-changing device out of operative relation
with the looper-as, when a lock-stitch is being made-for actuating the tension
device M to increase the stress thereof upon the needle to a definite extent.
The tension device shown in the drawings comprises two tension-plates 80
and 81, one of which, as 80, is fixedly supported, and the other of which, as 81,
is supported for movement upon the one 80; and the tension-regulating device
comprises a lifting-rod 82, secured at its lower end to the throw-out device 66
of the stitch-changing device, and having its upper end extending through two
tension-plates; an adjusting nut 83, screwed upon the upper end of said rod;
and a spring 84 interposed between the adjacent end and the movable tension-
plate 81.
It will be understood that the construction and organization of the tension device
and the regulating device may be materially modified without departure from
this invention.
It will be understood that when the stud 66 of the stitch-changing device is
shifted to throw said stitch-changing device out of operative relation with
the looper and actuating-cam 64 the stud 66 will be elevated, carrying with it the
rod 82 and the adjusting-nut 83, thus relieving the spring 84 and decreasing the
stress of the tension-plate 81 upon the upper thread a definite amount, the amount
being determined by the range of movement of the rod 82, as will be readily
understood.
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
1. A stitch-making mechanism embodying a looper and a resilient yieldable
device disposed to engage the loop of the needle-thread and hold the same under
tension during a portion of its passage around said looper.
2. A sewing-machine looper having a shiftable looper-reactionary loop-taker
or hook and a stop for limiting the movement of said hook.
3. A rotary sewing-machine looper having one or more peripheral loop-1
receiving openings one wall of which opening terminates in a loop-taker or hook,
combined with a loop-tensioning device disposed between the hook and the
inner wall of the recess and adapted for receiving the loop from said hook at a
predetermined point in the movement of said hook and for holding the same
under tension throughout a predetermined portion of the movement of said loop.
4. A sewing-machine looper having a plurality of circumferentially-disposed
loop-carriers each of which embodies two oppositely-disposed hooks one of which
is movable toward and away from the other whereby the distance between loop-
holding portions of said hook may be varied to compensate for the difference
in the lengths of thread reaching from adjacent loop-carriers in forming different
kinds of stitches.
5. In a stitch-making mechanism, the combination, with a rotary looper having
a circumferentially-disposed loop-taker adapted for carrying a loop to a fully-
drawn out position, of two successively-effective yieldable devices disposed to

page_text: engage the loop at successively-different positions and for holding the same under
tension through successive portions of the stitch-making operation.
6. A stitch-making mechanism including a rotary looper having two oppositely-
disposed hooks separated by a loop-receiving space, one of which hooks is fixed
and the other of which is yieldable in the direction of rotation of the looper and
is adapted for movement toward and away from the fixed hook whereby to take
up slack in, and compensate for differences in the lengths of, the loop, and a
yieldable loop-tensioning device supported in operative relation with one of said
hooks, and effective at a predetermined point in the orbit of said hook for engag-
ing the loop and for holding the same under tension during a predetermined
portion of the stitch-making operation.
7. A stitch-making mechanism including a looper having in the side face
thereof a series of driver-sockets or recesses the adjacent faces of the end walls
of which are spherical, and a driver having a series of teeth or projections the
outer and inner end faces of which correspond in structure to the wall-faces of
the looper-recesses and co-operate with said faces to support the looper.
8. The combination of a looper and a co-operative looper-driver supported with
their axes oblique to each other, one of said members having in one face thereof
a series of peripheral sockets, the inner and outer end walls of which are curved
transversely in concentric arcs, and the other of said members having a series of
driving teeth, the outer and inner end faces of which are curved transversely in
concentric arcs and are adapted to co-operate with the curved walls of the other
member to support the latter during rotation; means for guiding and preventing
lateral movement of the looper; and means for rotating the looper-driver.
9. A stitch-making mechanism embodying a rotary looper adapted for carrying
two loops simultaneously, and means independent of the looper for engaging one
loop and for holding them in such position that the succeeding loop will during the
rotation of the looper pass therefrom.
10. A stitch-making mechanism including a rotary looper having means for
carrying successive loops; independent stitch-changing device for diverting one
of said loops transversely of the needle path whereby the next loop will pass
through the diverted loop and enable the mechanism to form a chain-stitch, and
means for shifting the stitch-changing device into and out of operative relation
with the looper.
11. A stitch-making mechanism including a reciprocatory needle; a rotary
looper having a series of peripheral loop-takers or hooks; a stitch-changing
device having a loop-diverter supported for oscillatory movement in juxtaposition
to the path of the looper; means for actuating the stitch-changing device to
cause the loop-diverter to engage the upper portion of the loop and carry the
said portion forward to a point in advance of the vertical path of the needle and
thereby permit a succeeding loop to pass through a preceding loop, and said loop-
diverter having a hook at the working end thereof for positively holding the loop
in a diverted position until the succeeding loop passes therefrom.
12. A stitch-making mechanism including an adjustable tensioning device and
automatically-operable means for actuating the tension device to vary the resis-
tance or effective tension of said device concurrently with changes in the form
of stitch.
13. A stitch-making mechanism including a stitch-changing device operative
for effecting a change in the form of stitch being made, and a tension device
automatically controlled by the stitch-changing device for varying the resistance
of the tension device predetermined amounts in accordance with the kind of stitch
being made.
14. In a sewing-machine a looper mechanism including a rotary looper and a
looper-actuator; a stitch-changing device operative for deflecting preceding loops
so that succeeding loops will pass through the same to form a chain-stitch; an
adjustable tension device including two tension-plates and a spring for pressing
the two tension-plates into contact; a tension-regulating device in operative con-

page_text: nection with one of the tension-plates and the stitch-changing device and operable
by said stitch-changing device for varying the resistance of the tension-plate
spring concurrently with the shifting of the tension device into and out of opera-
tive relation with the looper.
FRANCIS HENRY RICHARDS.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.