IMPROVEMENTS IN BUTTON HOLE ATTACHMENTS FOR SEWING MACHINES
Year: 1884

page_text: I WILLIAM HENRY GILBERT, of the City of Philadelphia in the State of
Pennsylvania, one of the United States of America, Machinist do hereby declare
the nature of my invention for "IMPROVEMENTS IN BUTTON HOLE ATTACHMENTS
FOR SEWING MACHINES" and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
This invention has. relation to button-hole attachments for sewing machines of
that class in which the cloth while being fed in the direction of the outline of the
button hole, at the same time receives a reciprocating or zig-zag motion in order to
produce the usual button-hole-stitching.
In button hole attachments of this class as heretofore constructed one method of
obtaining the requisite feed movement of the cloth plate and presser bar
corresponding to the outline of the button hole, has been effected through the
employment of a heart-shaped cam mounted on a spindle and connected by
operative link-connections with the cloth-feeding clamp.
In such attachments, the character of which is well understood, the expedients
for varying the length of the button hole have either required the use of different
sized heart-cams for every length of button-hole, or the employment of a complex
and unreliable system of connections between the cam and the feed-clamp.
The special object of my invention is to obviate the disadvantages following the
necessity of changing the cams to meet the requirements of work, or of employing
complex and unreliable connections, and with this object in view to provide an
adjustable heart-cam whereby, without displacement of parts and by a simple
variation in the position of the heart-cam, the feed may be regulated and made to
conform to button-holes of any length, within the possible minimum and maximum
capacities of the feed.
My invention accordingly consists partly in providing a button hole feeding
attachment for sewing machines with an adjustable, feed-controlling heart-shaped
cam and a yoke connected with a feed clamp; whereby through a simple adjustment
of the position of the cam, the movement of the feed-clamp may be regulated so
as to feed the cloth the distance required for buttonholes of various lengths.

page_text: My invention furthermore partly consists in the special constructions, and
combinations of parts pertaining to the other devices employed in a complete
buttonhole stitching attachment, as hereinafter fully described.
In the accompanying drawings
Figure 1 is a perspective view of the attachment complete, but detached from a
sewing machine.
Figure 2 is a plan of the same.
Figure 3 is a vertical longitudinal section of the attachment.
Figure 4 is a side elevation with certain portions broken away.
Figure 5 is a plan of the base plate of the attachment with ratchet-wheel, tappet,
lever and pawl.
Figure 6 is a plan of a part of the base plate and of certain details of the
mechanism.
Figure 7 is an inverted plan of the clutch-wheel.
Figure 8 is a plan or top view of the clutch-wheel.
Figure 9 is a plan of the clutch-wheel with the heart-cam and slotted yoke.
Figure 10 is a side elevation of the stop-cam.
Figure 11 is a side view of the lever through which motion is obtained from the
needle bar of the sewing machine for the attachment.
Figures 12 and 13 are, respectively top and bottom views of the feed-slide-
carrier.
Figure 14 is a vertical longitudinal section of the carrier.
Figure 1a is a perspective view of a sewing machine with the button hole
attachment described herein in working position the latter being of the modified
construction referred to in the second part of the following description.
Figure 2 is a plan view of the base-plate with the clutch-wheel, heart-cam, and
friction-brake as referred to in the second part of the description.
Figure 3a is a plan view of the feed-slide carrier with the attached spring-arins
or levers.
Figure 4a is a side view of the same.
Figure 5 is a plan view of the base-plate referred to in the second part of the
description with the ratchet-wheel, modified form of tappet-wheel friction-brake
and pawl and lever.
Figure 6a is a side view of the clutch-wheel and friction-brake of the modified
appliance.
Figure 7 is a plan view of the base-plate feed-slide-carrier and other appurtenant
devices of the modified appliance.
Figure 8 is a perspective view of the friction brake..
Figure 9 is a vertical section of the clutch-wheel of the modified appliance.
Figure 10a is a vertical central section of the heart-cam and slotted slide.
In sheet 1 of the drawing, A designates the base-plate of a buttonhole feeding
attachment constructed and adapted to take the place of the usual slide in the cloth-
plate of an ordinary sewing machine when the latter is to be used for button-hole
stitching purposes. The base plate A carries all the parts pertaining to my
improvements. B is a carrier or frame pivotted thereon by means of pivot stud a
and screw b¹. B¹ designates the button-hole feed-plate, arranged to slide in grooved
guides B, B2, formed on the frame B and carrying the presser-foot B³ and the
presser lever B³, said parts constituting, a clamp, by which the cloth is held
and fed.
C is a standard rising from one side of the base plate A, and carrying the
lever C¹ having its arm c extended forward and forked as shown at c¹ for connection
by set screw with a vertically reciprocating needle-bar of a sewing machine,
Motion to the moving parts of the feeding devices is conveyed from the needle
bar of the sewing machine through the lever C₁ as is usual in button hole feeding
attachments.
'
D designates a post rising from, and rigidly secured to, the plate A. Upon this
post are journalled the six-toothed. ratchet-wheel D' and the three-toothed tappet

page_text: wheel or triangular cam D, the latter above the former and fastened thereto, so
that both turn together, the teeth of the latter being rivetted in position. A pair of
pivotted bars or levers E E embrace the tappet and are notched at their free ends,
as shown at d d for the engagement therewith of the tappet teeth, being pivottally
secured to the frame B at their opposite ends. As the tappet wheel turns it
engages with or presses upon and against the arms E E alternately, and through
them imparts to the frame or carrier B a vibratory motion, which is also com-
municated to the feed-plate B¹, as the latter moves with the said carrier. Thus.
the movement of the feed-plate, and of the cloth, is in a zig-zag line, to which the
stitching corresponds. In order to stitch both sides of the buttonhole, one side
after the other, the feed plate requires to be shifted laterally at either end of its
path, and such shifting and consequent travel of the feed-plate are accomplished
by the following means, viz:-
Upon the post D is loosely fitted a collar or stop-cam F, recessed as shown
at f Figures 10 and 12, by having a segment removed from its lower portion.
Upon the inner sides of the guides B', and upon opposite sides of the collar F
there are studs g, g', Figure 13, one of which is adjustable by means of a
set-screw. g, and said studs are so placed that when the recess f is toward
either or both of said studs the latter may enter such recess. As the feed
plate B¹ moves in one direction of its feed the recess is toward the stud g,
and consequently the other stud g¹ is limited in its play by the wall of the
collar F in which the recess fis formed and by that portion of said wall opposite
to said recess.
Now when the collar F has been moved around, as hereinafter
explained, so as to allow both of the studs to enter its recess the movement of the
latter is only limited by the post D; hence the extent of their movements is
doubled, and, as the movement of the feed-plate is in keeping with the play of the
studs, the stitching is extended across the ends of the button hole, thus forming
the bars or finishing stitches of double length at the end of said button hole. The
rotation of the collar F being continued the solid portion of the wall of said collar
now opposes the stud g while the recess f faces the stud g¹. At this point the
feed-plate is on its return or backward movement, and, by the altered position of
the collar or stop-cam, has assumed the shifted condition referred to already.
Lateral reciprocation of the feed-plate then takes place, under the limitation
effected by the opposition of the solid portion of the wall of the collar F to the
stud g, and is confined to the side of the button hole corresponding to the position
of the stud with reference to the central line, and stitching continues on this side
of the buttonhole until the feed-plate has reached its backward limit, when the
recess again allows both studs g g₁ free play and permits the feed-plate to
reciprocate or cross both sides of the button hole, so as to stitch the end where the
stitching was begun.
The forward and return movement of the feed-plate is effected by the mechanism
which embodies the principal feature of my invention, that is the adjustable
heart-cam and yoke. Said cam is represented at H and the yoke at H¹. The
former is carried by a cylindrical head or wheel H³, which is mounted on the
post D, so as to turn freely thereon, and held in position by a screw d which enters
said post, its head fitting in a countersink in the wheel H. The heart-cam H is
attached to, or inade integral with, a dove tailed slide H³ fitting a correspondingly
shaped channel I (see particularly Figure 9) formed on the upper side of the
head H2 and traversing the same diametrically. This slide is slotted at / for the
passage of a set-screw i, by means of which said.slide is secured at any position in
the channel I, and, by loosening which, said slide may be adjusted to regulate the
distance of the heart-cam from the centre of motion of the head H. The greater
the heart-cam's distance from the centre of the_wheel, the greater will be the radius
of the circle described by it, and vice-versa. The yoke H¹ consists of a plate or
frame having a transversely slotted portion with slotted sides which embrace the
heart-cam H. At its rear or opposite end the yoke is secured to the feed plate B¹

page_text: as shown. As the wheel H2 rotates in the direction indicated by the arrows in
Figures 2, 8 and 9 motion is communicated through the heart-cam to the yoke H',
producing a rectilinear movement of the latter and the feed-plate B₁, a forward
inovement of the yoke and feed-plate taking place during half a revolution of the
wheel H2 and a reverse movement during the other half revolution.
The length
of the stitching of the buttonhole depends upon the distance travelled by the feed-
slide, and this distance is regulated by the adjustment of the heart-cam, which,
according to its position with reference to the centre of the wheel H³, produces a
greater or lesser travel of the yoke and slide. The wheel H³ is made in the form
of a friction clutch and comprises the recessed cap' portion 2. having the annular
flange ³, the split ring *, lever 15 to press said ring into frictional contact with the
flange, and the yoke or hub h carrying said ring, (Figures 3 and 8). Said hub
is loosely swiveled on a central boss depending from the cap h². By moving the
lever h³ in one direction, so that its short arm will impinge against the stud i on
the hub the split ring is expanded against the flange h³, and, by continuing the
movement, the wheel h² is turned. The outer end of the lever h³ fits to one side of
a roller k carried on the projecting end of lever C, so that the movement of the
latter in one direction will produce a forward movement of said lever h³. A spiral
spring Figures 2, 3 and 4, is employed for the automatic retraction of the lever 15
without moving the wheel H' after each movement of the latter, and a suitable
adjusting screw 12 carried on a standard 2, attached to the base plate A, serves as
means for limiting the backward stroke of the lever, and the consequent extent of
revolution given to the wheel through each forward stroke. Hence by adjusting
the screw I² the spacing between each stitch, or the fineness of the stitch is
regulated. The six-toothed ratchet wheel through which motion is imparted to
the tappet or three-toothed can D² is loosely swiveled on the post D, said wheel
and tappet being fastened together, and actuated from the lever C² and spring.
pawl Cs pivotted on said lever C2-sec Figures 1, 2, 3, 4, 5 and 11. The lever C¹
has a short depending branch c² (Figure 11) which is forked, and embraces the
lever C², so that upon each descent of the needle-bar of the machine the pawl C¹³
will be thrown back and into engagement with one of the teeth of the wheel D¹,
wbile upon the ascent of the needle-bar the ratchet-wheel will be turned the
distance of a single tooth. This movement being communicated to the tappet and
thence to the reciprocating feed-slide, a lateral movement of the latter takes place
upon every rise of the needle. To impart motion to the clutch-wheel H³ the
lever C is extended laterally through a slot C³ (see Figure 11) in the standard C
and is armed with an anti-friction roller k arranged as shown with reference to the
curved arm of the clutch-lever 5. As the lever C is drawn forward in giving an
impulse to the ratchet wheel the friction roller k comes into contact with and
presses against the lever h³, moving the same forwardly and thus effecting a partial
revolution of the clutch-wheel H². The upper end of the stop-cam F enters a
chamber in the central boss of the clutch-wheel H2 and has a recess into which
enters a pink depending from the wheel H2 and serving to interlock the wheel
and stop-cam so that they will move together, the cam being designed to receive its
motion from the clutch-wheel see Figure 7. A spring maintains the stop-cam in
its position on the post D, but, should one of the stops g g¹ come into contact with
one of the edges of the stop-cam F, the spring will yield sufficiently to allow
said stop-cam a slight rotary motion, which will afford. relief to the contracting
stop y or g¹.
In Figures 1 to 10 inclusive, sheet 2 of the drawings, I have shewn, and will
now proceed to describe, certain additions to, and modifications of, the mechanism
herein before referred to, as follows.
A friction-brake is shown at A2, Figures 2, 5, 6; 7*, and 8* and consists of a
standard of steel or other spring metal secured to the plate B and having a curved
shoe b concentric with the friction clutch C and arranged to impinge against the
periphery of the latter. This pressure of the shoe produces a friction which resists..

page_text: the rotation of the clutch sufficiently to prevent the latter from being thrown too
far backward or forward by its actuating mechanism, thereby maintaining the
uniformity and regularity of the feed.
In my previous description of the friction-clutch I have shown that it comprises.
a split ring which is caused to expand against the inner wall of a surrounding
casing. Under such described construction this ring has a tendency to drop out of
the casing and retard the zig-zag movement. of the slide. To prevent this
I construct the ring C³ with an annular groove c³, and provide the casing C with
two screws c which pass through its wall or depending flange and enter said groove.
In the subject of my first description the tappet-wheel is shown as consisting of:
a three-toothed or triangular cam with the studs or teeth separately rivetted upon
its upper surface, but for the purposes of simplicity and economy of construction
I may produce the tappet wheel shown at D³, Figures 5", 7ª, from a single piece
or disc, by cutting or otherwise forming the teeth d³ on its periphery as shown, and
so omit the separately attached studs which are somewhat difficult and expensive.
to form and apply.
In my said first description and the drawings illustrating the same the tappet is
shown and described as having three teeth or points, which come successively in
contact with the ends of the levers and so produce a zig-zag movement of the slide
carrier. Said tappet is carried on a ratchet, so that both travel together, movement
being imparted by a pawl engaging with the ratchet. This pawl is connected
with, and obtains its movement from, a needle-bar of the machine. The ratchet in
my said first description is represented as having but six teeth and the tappet only
three, and the arrangement and relation of parts are such that the pawl takes hold
of, and begins to pull, the ratchet the moment the needle-bar begins its upward
movement.
As the ratchet, as already mentioned, carries the tappet, it follows that, with the
previously described construction, the carrier is oscillated, partly, or the oscillating
movement is begun before the needle has arisen from the fabric. As a modification
I may, however, make the ratchet with ten teeth and the tappet with five and
allow the pawl the same extent of movement as heretofore. But, whereas, with
the construction first described the pawl engages with the ratchet upon the instant
of completing its forward movement, with the modified construction just mentioned
the pawl has lost motion, that is, on going forward its toe passes some distance
beyond the tooth with which it next engages, and, when it reverses, it travels
back wardly some distance before engaging with the ratchet tooth. During this
interval of lost motion the needle bar rises sufficiently for the needle to clear the
fabric, after which the zig-zag movement of the carrier is begun.
In my said first description the levers upon which the tappet acts to produce the
zig-zag motion of the slide carrier are pivotted to the under side of the feed slide
carrier, and coupled together by a spiral spring which controls the yielding move-
ment of each alternately and retracts it to its normal position. I have found that
this spring can be dispensed with, and hence may construct said levers of' spring
steel, in which the required elasticity is inherent in the metal F¹, F¹. Figures 1º, 3º,
4a, 7a designate said levers, rigidly secured by screws f to the sides of the feed-
slide carrier G, and at their forward ends bent inward and under said carrier
towards the tappet wheel. As the tappet-teeth in succession strike the ends of the
levers alternately the carrier is oscillated or moved from side to side, resulting in
the production of the zig-zag movement of said carrier. When the end of one of
the levers is in impinging contact with a tappet tooth and is pressed out by the
latter a tension is produced in said lever (owing to its elasticity) which causes it to
bear against the tooth and to hold the carrier in its position while a stitch is being
formed and until another tooth comes in contact with the lever on the opposite side
and communicates a reverse movement to the carrier.
H* designates the pawl through which motion is imparted to the ratchet D³. In
the attachment first described I have shown, a spring attached to the lever C³ upon
which the pawl is mounted; for the purpose of throwing the point of the pawl into

page_text: engagement with the ratchet during the forward movement of said pawl, such
spring being arranged to bear against the short arm of the pawl. In the modified
construction shown in Figure 5a, I discard said spring, and in lieu thereof substitute
a post or stud i fixed in the base-plate B6 aud rising so as to intercept the short
arm of the pawl while the lever H³ is moving forwardly, thus causing the point or
tooth of the pawl to engage itself with the teeth of the ratchet.
The lever H³ is cut or recessed at h to allow space for the said stud or post and
permit the former freedom of movement.
With reference to the heart cam, Figure 2 shows means whereby it is adjusted,
and the modification or change consists in discarding the slotted portion of the
dovetailed slide, and securing said heart-cam K in place by means of a screw t
passing through its centre and coming in contact with the surface of the dovetailed
groove . By forcing the screw downward upon the surface of the groove, the.
dovetailed slide L, upon which the heart-cam rests is pressed upward at its edges
against those of the groove and thus securely retained.
In my first description the slide carrier (shown at B in Figures 3, 12, 13, 14) is
provided with a fixed shoe or projection on the inner side of one of its side bars.
and an adjusting screw carrying, a shoe on the opposite side. This gives an
adjustment on only one side of the slide carrier. As a modification thereof I may,
as shown in Figure 3a, provide two adjusting screws g³, g³, on opposite sides of the
slide and dispense with the shoe. By means of the two screws I obtain a double
adjustment on both sides, securing an equal throw in both directions of the carrier
in effecting the zig-zag movement, and dispensing with the adjustment of the other
parts heretofore required.
As a modification of the means.for fastening the slide L on which is carried the
heart-cam said slide may be formed with a slit or kerf extending from the central
screw hole to one of its edges. The screw which passes through the heart cam is
made tapering at its point and when the latter enters the screw-hole in the slide it
causes the edges of said slide to expand or press outwardly against the walls of the
dove-tailed groove k³.
Having now particularly described and ascertained the nature of my invention
and in what manner the same is to be performed, I declare that what I claim is :-
First. In a button hole stitching mechanism, the combination with the feed-slide
and a wheel or disc through which the same receives motion from the working
parts of the machine, of a yoke secured to the said feed-slide, and having a
transversely slotted head and heart-cam secured upon the face of said disc and
diametrically adjustable thereon, substantially as shown and described.
Second. In a button-hole stitching mechanism, the combination with the friction-
clutch or rotary head C and devices for actuating the same, of a spring brake or
friction shoe A impinging against the same to prevent forward or backward
abnormal movement thereof, substantially as described.
Third. In a button-hole stitching mechanism having a slide carrier adapted and
designed to be oscillated, the combination with the said carrier of a pawl, a ratchet
and a tappet-wheel, said pawl being arranged relatively to the ratchet so as to
bave lost motion on its return stroke, substantially as shown and described.
Fourth. In a button-hole stitching mechanism, the combination with the feed-
slide carrier and the tappet through which the said slide is oscillated, of the
levers F¹, F¹, consisting of spring or elastic bars rigidly secured to the said carrier.
and bent inwardly and beneath the carrier, substantially as described.
Fifth. In a button-hole stitching mechanism, the stud or post in the base
plate B6, in combination with the pawl H carried by lever H³, substantially as
described.
• Sixth. In a button hole stitching mechanism, the combination with the heart-
cam and its dovetailed supporting slit-slide and the correspondingly grooved
friction-clutch casing, of the tapering pointed screw * passing through the centre
of the said cam and operating to expand the slit supporting-slide, as shown and
described.

page_text: Seventh. In a button-hole stitching mechanism, the combination with the slide
carrier, of two adjusting screws g³, g³, one on either side of the said carrier, for the
purpose of securing a double adjustment thereof, substantially as shown and
described.
Eighth. In a button-hole stitching mechanism, the combination in the friction
clutch in the feed-motion of a button-hole sewing machine, of an expanding ring e³
having an annular groove c with the casing Chaving screws c, substantially as
shown and described.
Ninth. In a button-hole stitching mechanism, the revolving stop-cam or collar F
having a segmental recess, in combination with the pin k¹ and relief spring ³ to
interlock the stop-cam and feed wheel, as described.
HASELTINE, LAKE & Co.,
For the Applicant.