Improvements in Button-hole Attachments for Sewing Machines.
Year: 1889

page_text: *ate of Application, 4th Oct., 1889-Accepted, 22nd Feb., 1890
COMPLETE SPECIFICATION.
Improvements in Button-hole Attachments for Sewing Machines.
We ELMER FLETCHER of Needham, in the County of Norfolk Machinist, and
GEORGE WALLINGFORD HILLS of Boston, in the County of Suffolk, Merchant, both
in the State of Massachusetts, one of the United States of America do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
This invention has for its object the production of a novel attachment for
application to ordinary sewing machines, and by which to stitch material for the
production of button-holes.
The attachment herein described is especially devised to move the attachment and
the fabric held by it under the needle bar in such manner as to produce a button-hole
such as described in English patent No. 13,618, dated September 20-1888, but by
altering the shape of the shaping cam the said attachment may be readily adapted to
stitching button-holes with both ends alike, or of usual shape.
In this invention, it has been aimed to secure simplicity of construction and
durability of parts, and this has been accomplished with but comparatively few parts.
This invention consists in a button-hole. attachment containing the following
instrumentalities, viz. a base-plate having a stud; a slotted yoke; a cloth-clamp
having a shank engaged by a projection of the said yoke; a depth stitch cam
uniform in cross section at all points to fill from side to side the slot in the said
yoke to thereby enable the cam to move the said yoke positively and prevent lost
motion; a ratchet wheel connected to the said cam and movable with it about the
said stud; means to move the said ratchet wheel; and means to move the cloth-
clamp longitudinally, as will be described.
Also, in a button-hole attachment, a base plate having a stud; a depth stitch cam
uniform in cross section in every diameter; a ratchet wheel connected to the said
depth stitch cam and movable together about the said stud; a yoke having a pro-
jection a cloth-clamp having a slotted shank engaging the said projection; a cam
having a slot; a bridge plate having a roller stud; means for rotating the cam plate
and the depth stitch cam; and means to move the cloth-clamp longitudinally, as
will be described.
Also, in a button-hole attachment, a base plate having a stud; a depth stitch cam
and connected ratchet wheel; a yoke moved by the said cam and having an ear and a
bridge; a fulcrum-plate; a stud to serve as a fulcrum for the said yoke; a cam
having a cam groove; a bridge plate; a roller stud thereon entering the said cam
groove; means to rotate the said cam intermittingly; and means to effect the adjust-
ment of the said fulcrum block whereby the space left between the inner edges of
the depth stitches along the substantially straight sides of the button-hole is left
uniform notwithstanding differences in length of button-hole or the length of the
depth stitch; as will be described.
Also, in a button-hole attachment, a base plate having a stud; a depth stitch cam
and its co-operating ratchet wheel; means to rotate them; a yoke having a pro-
jection; a fulcrum plate for the said yoke; a bridge plate having a roller stud;
a grooved cam; means to rotate it; a friction plate co-operating with the said
cam; a cloth-clamp having a slotted shank engaged by the said bridge plate; a
slotted plate secured to the said cam; an adjustable screw having a cam; and a
slotted arm secured to the cloth clamp, to operate as will be described.
Fig. 1 is a top or plan view of a button-hole attachment embodying my invention.
Fig. 2, a side elevation thereof.
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page_text: Fig. 4, details of the clamping and adjusting nut forming the connection between
the slotted plate to be described and the arm of the clamp.
Fig. 5, is a plan view of the attachment with the arm of the clamp and the slotted
plate and cam removed.
Fig. 6, is a detail in plan view chiefly to show the rear end of the attachment and
the cam yoke and means for moving it and holding it in adjusted position according
to the length of the depth stitch.
Fig. 7, is a top or plan view of the cam and cam plate thereon.
Fig. 8, an underside view of the parts shewn in Fig. 7.
Fig. 9, shews the friction ring detached.
Fig. 10 shews a piece of cloth stitched to form a button hole.
Figs. 11, 12 and 13, shew details separately.
Fig. 14, shews a cross sectional view of portions of the apparatus shewn by Fig. 5.
A is the base-plate of the attachment, A' a plate secured to its under side to take
the place of the usual shuttle-race slide when the latter is removed to apply the
attachment to the machine, and A' is an upright of the base.
B is a lever having its fulcrum on a stud screw B', and provided at its lower end
with a pawl B2, see Fig. 5, pivoted at B3 and acted upon by a spring B.
The lever B is forked at its other end in usual manner to be actuated by the usual
needle-bar nut or by a projection from the usual needle-bar of the machine.
The bed-plate has a needle-hole 2, and erected upon the said plate is a shouldered
stud or post a, shown clearly in Fig. 3.
The bed plate has a lip 3, a pin 4, and a split pin 5, and to the latter is secured a
detent spring 6.
The stud a receives upon it next to the bed-plate the depth stitch cam a¹, the shape
of which is best shown in Fig. 6, it having as represented five like faces 7, on its
periphery, separated by five points or corners 8, the said cam being of uniform
diameter in every cross section so as to completely fill the slot or space between
the sides of the yoke C, as shown in Fig. 6, the said cam deriving its step-by-step
rotation, from the pawl B2 acting on the teeth of the ratchet wheel a, fixed to or
integral with the said depth stitch cam, and acted upon by the detent 6 to avoid back
motion.
By making the depth stitch cam of uniform diameter in any and every diametrical
cross section, I am enabled to move the yoke positively without any lost motion,
which result could not be accomplished by a triangular cam which was not of a
uniform length in every diametrical cross section.
In its rotation, the depth stitch cam vibrates the yoke C and causes the projection C¹
of the said yoke, the said projection being between the side bars of the shank D of the
cloth clamp, to vibrate the said clamp.
The projection C moved by the yoke, as described, acts in turn to convey its lateral
motion to the clamp, and at the same time, this projection also serves as a fulcrum on
which the shank of the cloth clamp rocks as the clamp is shifted to outline the shape
of the button-hole.
This latter movement is given to the clamp chiefly through the cam Ds, it having a
groove 10 in which enters a roller stud D₁ of a bridge" piece D' which embraces
loosely the shank D of the cloth clamp to be described.
The bridge piece DB shown Jdetached in Fig. 12, has loosely connected to it in
any usual or desired manner, as by a rivet 46, an arm r, which at its outer end has
attached to it a stripper plate p² the said plate having a slot at right angles to the
length of the button-hole; the said slot being as long as the distance between one and
the other side of the slot in the foot e¹.. The inner edges of the side pieces of the
foot are grooved or chambered, as best shewn in Fig. 14 to receive this stripper plate
loosely so that the clamp can easily be moved longitudinally with relation to the stripper-
plate, and the stripper plate can rise and fall with the top plate of the clamp when
opened and closed to hold the material to be stitched.. The stripper plate does not
follow the clamp in its longitudinal movements but does in its vibrations. The under
side of this stripper-plate is so arranged as to just touch or substantially so, the

page_text: material being stitched, but so as not to bear upon it and produce friction to detain
the material while the clamp is moved longitudinally to take the material with it.
This stripper-plate, as has been stated, prevents the material being stitched from being
lifted from the base plate containing the needle-hole, by the needle in its upward
movement, and the material being kept down as described, or prevented from rising,
stitches are not skipped. If the material is permitted to rise with the needle, the loop
in the needle thread at the under side of the material has given to it an additional lift
due to the rising of the cloth, which shortens the loop so that the shuttle or under
thread carrier used in the sewing machine to which the attachment is applied, does
not have the full amount of loop to enter.
The cam D is fitted to turn on the stud a just above the second shoulder from the
bottom of the said stud.
The cam D2 is held down on the said stud by a friction washer 12, which is held in
place by a screw 13, see Fig. 3, which enters a threaded hole in the said stud.
The ratchet wheel a² has ten teeth so that the depth stitch cam a¹ is moved just far
enough to enable it to move the yoke and cloth clamp in one direction laterally and
then permit it to remain at rest for one descent of the needle, and then when the
needle rises from the material, move the yoke and cloth clamp in the opposite direction
and leave it at rest while the needle again descends through the material and rises
therefrom.
The ratchet wheel a² it will be noticed derives its motion directly from the pawl
pivoted on the lever B, and without the intervention of any other devices, thus
simplifying the attachment, and the length of the pawl and the position of the stud a
are such that the ratchet is turned by the pawl only after the needle-bar which
actuates the lever B, has risen sufficiently to remove the needle from the material,
the pawl not acting to turn the ratchet until after the needle is fully out of the
material.
The yoke has a lip C² shewn best in Figs. 5 & 6, provided with a hole which
receives a fulcrum pin. 14 of a fulcrum block C³, having, as shown, a slotted
extension (which receives the guide pin 4 and has extended through it the shank
of the set screw C which is used to hold the fulcrum block in adjusted position,
the nearer the fulcrum pin 14 to the stud a the longer the depth stitch and
vice-versa. The fulcrum block crosses and overlaps the yoke C and aids in keeping
it uniformly seated on the bed-plate. The yoke has an ear 16 which extends under
the lap 3 which further aids in keeping the yoke seated on the bed-plate.
The adjustment of the fulcrum block carries with it the projection C which
constitutes the fulcrum for the shank of the cloth clamp and as both fulcra 14 and C₁
are adjusted in unison by one and the same operation, it follows that the rows of depth
stitches at each side the center of the button-hole are at uniform distances apart in all
sized button-holes along the straight edges of the button slit and this whatever may
be the length of the depth stitch, so that the button-holes, stitched by the use of the
attachment are uniform and symmetrical leaving just enough space for the cutting of
the fabric after the stitching has been completed.
The stud a above the ratchet wheel aand. between it and the shank D of the cloth
clamp is surrounded by a washer d on which rests the slotted shank D..
The shank D is bent downwardly at 19, see Fig. 2, to form the under-half e of the
cloth clamp, the said part e resting against the bed-plate and is cut out to leave a
space about the needle-hole, through which space the button-hole is stitched.
The upper part of the clamp consists of an open foot el pivoted loosely by pins e² on
spring arms eattached by screws 22 to the shank D.
The inner edges of the foot el are down-turned in usual manner to force the material
down through the opening in the part e and against the bed-plate.
The bridge D is slotted centrally and embraces the stud a, the width of the slot in
the said bridge piece being just sufficient to fit the said stud so as to prevent any
movement of the bridge pin in the direction of the length of the bed-plate, but the
said slot is sufficiently longer than the diameter of the said stud to enable the. shank D

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of the cloth-clamp to be moyed laterally with relation to the said stud as by the action
of the cam D2 on the roller stud of the bridge pins.
The cam groove 10, herein shown, is of such shape as to cause the cloth to be swung
or moved about on the bed-plate and with such relation to the needle-hole 2 and the
stitch forming device of the sewing machine as to enable the shape of the button-hole
to be defined.
The cam D derives its intermitting rotation one step during each ascent of the
needle-bar of the machine, by, as herein shown, the action of a ring f shown separately
in Fig. 9, on which is pivoted a dog f¹ acted upon by a spring f' connected to the
ring, the free end of the said spring acting on the said dog at a point between the
center of the ring and the pivot f on which the said dog turns, the said spring
normally acting to keep a part of the end 23 of the dog pressed against the periphery
of the cam D.
The dog is extended outwardly through a slot 24, see the detail Fig. 11, in the
lever B, the said lever having an adjusting screw g, by which the effective length of
the said slot may be regulated.
The point of the said screw g meets the dog f¹ as the lever B is moved by the
descending needle-bar and the ring and dog are moved backwardly over the cam D²
held in place by the friction washer 12, but as the needle-bar rises it moves the
lever B in the opposite direction and the said lever at the end of the slot meets the
dog, and causes it to firmly engage the periphery of the cam D2 and rotate it for
one step.
To effect the longitudinal movement of the clamp according to the length of the
button-hole, I have provided the clamp or the shank thereof with a rigid arm / slotted
at transversely to the slot in the shank D) and in this slot I have placed a triangular
cam 26 mounted loosely on a screw 27 having an oblong thin head 28 which slides in
a groove 29 made in a plate m shown as countersunk into the upper face of the cam D³
and made adjustable with relation to the said cam by a screw 30 in a slot 31 of the
said plate, the screw entering the cam D².
The triangular cam 26 has at its underside, see dotted lines Fig. 7 and full
lines Fig. 4, a projection marked 31 in Fig. 4, which projection enters the upper side
of the slot 29 in the plate m and prevents any rotation of the said cam 26 with relation
to the said plate.
The screw 27 has applied to it a thumb nut 32 rotation of which in one direction.
enables the head of the screw to be moved in the slot 29 toward or from the center
of the plate m and the center of rotation of the cam D2 to thereby cause the cam 26,
it acting as a crank pin in the slot ¹, to move the clamp a greater or less distance
longitudinally during any one rotation of the cam D³.
Adjustment of the plate m on the cam D enables the slot 29 to be correctly located
with relation to the cam groove 10 and when over a correct position is secured there by
the screw 30.
The clamp may be opened and closed at proper times by the usual lever n.
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: In a button-hole attachment the following instrumentalities, viz. the base-
plate having a stud a; the slotted yoke C; the cloth-clamp having a shank D engaged
by a projection of the said yoke; the depth stitch cam a uniform in cross section at,
all points to fill from side to side the slot in the said yoke to thereby enable the cam
to move the yoke positively and prevent any lost motion; a ratchet wheel connected to
the said cam and movable with it about the said stud ; means to actuate the said ratchet
wheel; and means to move the cloth-clamp longitudinally, to operate, substantially as
described.
2: In a button-hole attachment, a base-plate having the stud a; the depth stitch
cam a uniform in cross section in every diameter; and the ratchet wheel a² connected
to the depth stitch cam and both movable upon the said stud; the yoke Û having the
ن

page_text: projection C; the cloth-clamp having a slotted shank D engaging the said projection;.
and the cam D having a slot 10; and the bridge plate having a roller stud; combined
with means for rotating the cam-plate and the said depth stitch cam; and means to
move the cloth-clamp longitudinally, substantially as described.
3 The base-plate; its stud a; the depth-stitch cam; the connected ratchet a'; the
yoke C moved by the said cam and having an ear C and a bridge C¹; the fulcrum
plate C3; the stud 14 serving as a fulcrum for the yoke C; the cam D' having a cam
groove 10 the cloth-clamp having the slotted shank D; means to move the cloth-
clamp longitudinally; the bridge plate; the roller stud D' thereon entering the said
groove 10, means to rotate the said cam D' intermittingly; and means to effect the
adjustment of the said fulcrum block whereby the space left between the inner edges
of the depth stitches along the substantially straight sides of the button-hole is left
uniform notwithstanding differences in length of the button-hole or the length of the
depth-stitch, substantially as described.
4-The base-plate A, having the stud a, the depth stitch cam and its co-operating
ratchet wheel; means to rotate them; the yoke C having the projection C¹; the
fulcrum plate for the said yoke; the bridge plate having a roller stud; the
grooved cam D²; means to rotate it; the friction plate co-operating with the said
cam; the cloth-clamp having a slotted shank D engaged by the said bridge-plate;
the slotted plate m secured to the cam D'; the adjustable screw therein having a cam
thereon; and the slotted arm¸h secured to the cloth-clamp, the combination being and
operating, substantially as described.
:-
5 In an attachment for holding material to be stitched in the working of button-
holes, a slotted foot-plate constituting part of a clamp, and a stripper-plate placed
loosely in the slot of the said foot-plate and adapted to substantially touch the upper
side of the material being stitched, the said stripper-plate being restrained from
longitudinal movement while the clamp is being moved in the direction of the length
of the button-hole slit.
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