Improvements in Button-hole Sewing Machines.
Year: 1895

page_text: Date of Application, 22nd Oct., 1895-Accepted, 23rd Nov., 1895
Improvements in Button-hole Sewing Machines.
We FRANK WILLIAM MUGFORD, of 21, Aldermanbury, London, E.C.
Manufacturer, and FREDERICK SIMMONS, of 9, Manor Place, Walworth,
London, S.E Engineer, 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 relates to improvements in that class of button hole sowing
machine described in the Specification of Letters Patent granted to the said
Frederick Simmons and dated the 29th day of April 1889, No. 7091.
In that machine the needle-bar is carried by a horizontal slide in the head of
the machine. This slide is reciprocated by a cam arting in conjunction with a
spring, the travel of the slide being controlled by stops acted on by the periphery
of the feed cam and by a cuived plate secured to the feed cam which forms steps.
These steps (at the proper moment) allow the needle-bar slide to travel twice the
distance necessary to form the button-hole stitch and so form the "barring " stitch
at the end of the button-hole.
"
Now, according to the present invention, the slide carrying the needle-bai always
reciprocates to an extent equal only to the length of the button-hole stitch, the
«bairing
stitch being formed by the 1cciprocation of the work-plate at the
required moment supplementing the reciprocation of the needle-bar slide, both
the needle bar slide and the work-plate being actuated by one cam.
In the accompanying drawings,
Figure 1 shows in rear elevation so much of a button-hole sewing-machine as is
necessary to illustrate the invention.
Figure 2 is a plan view of the same, and
Figure 3 is a partial sectional end view.
Figures 4 to 7 are separate views of certain details.
Figure 8 is a part diagrammatic rear elevation of the machine designed to serve
as a key to the movements of certain parts shewn in Figure 1, and
Figure 9 is an enlarged transverse section through the needle hole plate and
adjacent parts.
In these figures, A is the fiame of the machine and B the dring shaft mounted
in bearings in the frame. C is a toothed cam wheel mounted loosely on a stud
axle C, in the frame. This wheel (shewn in face view at Figure 4) receives rotary
motion through a pinion D on the diving shaft B. In one face of the wheel C is
formed a cam groove c, to receive two bowls, situated at diametrically opposite
points in the horizontal plane, and carried the one by a bare attached to an arm E',
carrying the slide E which imparts bouzontally reciprocating movements to the
needle bar E, and the other on a bar f connected by a friction device G to an
extension F of the work-plate carrier The baise and slide in guides in the
frame A. The arm E', besides carrying the needle bar slide, is also attached to
the shuttle box or race N which participates in the horizontal reciprocation of the
needle bar slide, for the purpose to be hereafter explained. The friction device G
consists of a screwed stud secured to the bar f and passing through a horizontal
slot in the caer F, a strong spring g being interposed between a nut on the stud
and the carrier F to give the necessary amount of fiction. H is the feed cam
mounted on an intermediate shaft II, carried in beatings on the main frame. To
the periphery of this cam is secured an adjustable curved plate similar to that
D 877

page_text: described in the Specification before referred to
The shaft H', is actuated by the
usual feed dog II, the outer end of which carries a bowl overlying a cam cl, loose
on the stud axle C, and in one with the cam wheel C. The inner end of the feed
dog grips the feed wheel H. The rotation of the cam e', will lift the feed
dog 11, and cause it to gup the feed wheel II', and so rotate that wheel and the
shaft H', carrying the feed cam II, the feed dog H³, being returned by the action
of a spring, as usual.
In the drawings we have shewn the ordinary friction feed as above described,
but we may substitute for this a ratchet feed, if thought preferable.
The feed cain H is of reversed spiral form and by one complete revolution
imparts feed motion to the work plate J in both directions lengthways of the
button hole through the medium of the lever I working on a fixed fulcrum í and
connected to the plate J by a bolt e', which is adjustable simultaneously in a slot
in said lever and in another slot in said plate so as to vary the ratio of the effective
lengths of the two arms of the level, thereby varying the amount of the feed
imparted in either direction by semi-evolution of the cam H to suit the length of
button-hole cut. The work is secured upon the work-plate J by means of the
apertured presser foot clamp K which is so jointed at & to an aim upon the piesser
rod A, as to be capable when depressed of adjusting itself to any inequalities in
the thickness of the material to be sewn. The presser rod A, which always tends
to rise under the action of the spring ³, and is depressed by the cam lever k³, 18
.mounted to slide vertically in the bracket K', fixed on the work plate J, in all
the movements of which it consequently participates.
The extension F of the work-plate cairier works in guides in the frame A, and
canies two jaws 1, 2, adapted to loosely embrace the body portion of the feed
cam II, for the purpose to be presently explained.
On otary motion being communicated to the cam wheel C, the groove c will
cause the bowls on the bars e and to alternately approach and recede from one
another, thus imparting opposite reciprocating movements to these bais, the bai e
being rigidly attached at the point a (Figure 2) to the arm E', carrying the needle-
bar slide, the latter will constantly reciprocate a distance equal to the length of
the button-hole stitch, but the bat being connected to the work-plate carrier F,
not rigidly but only by means of the friction device G, the reciprocating motion of
the bar will not be imparted to the work-plate so long as the jaw 1 bears on the
curved plate and the jaw 2 bears on the periphery of the feed cam H, or con-
versely so long as the jaw 1 bears on the periphery of the feed cam H and the
Jaw 2 bears on the plate , that is to say in the two positions shown respectively in
Figures 1 (or 8) and 6 which indicate the position of the parts when sewing one or
other side of a button hole, the reciprocation of the bar in these cases simply
overcoming the friction of the device G without moving the carrier F. As the
length of the button hole, although variable according to the effective length of the
lever I, always corresponds to a semi-revolution of the cam II, the action above
described with reference to Figure 1 (or 8) will continue until one side of the
button hole is completed, whereupon the semi-rotation of the feed cam will now
have brought the curved plate h into the position shewn in the detached view
Figure 5 in which position the plate is clear of the jaw 1, thus allowing the
friction device G to come to effective operation and so cause the carrier F, and
with it the work-plate, to reciprocate under the action of the cam wheel C, the
combined travel of the needle-bar slide E and of the work-plate J in opposite
directions giving the required extent of traverse for the formation of the "barring
stitch across the end of the button hole. The sewing of the "bar" being com-
pleted the continued 1otation of the feed cam H will bing the curved plate h into
the path of the jaw 2 on the carrier F (see Figure 6) thus shifting the work-plate
so as to bring the work clamped thereon into position for sewing the opposite side
of the button hole, and ailesting the transveise reciprocating motion of the
work-plate J and its carer I', as before The continued 10tation of the feed
cam H during the sewing of the second side of the button hole will now bring the
"

page_text: parts into the position shewn at the detached view Figure 7 where the curved
plate has passed clear of the jaw 2 so allowing the work-plate carrier to
eciprocate as described with reference to Figure 5 for forming the "bar" at the
other end of the button hole, thus completing the work.
Preferably we commence operating upon a button hole with the parts occupying
the position corresponding to that indicated in Figure 5 and end up at the same
position.
and
A further improvement consists in fitting to the work-plate carrier an adjustable
guillotine knife for cutting the button hole after the material has been placed in
the presser foot clamp and before sewing. This knife is best shewn at Figure 3
where the work plate is in the position it occupies immediately before the com-
mencement of the feed, which is the moment foi the cutting of the button hole to
take place. The blade L is mounted between guides formed on one side by au
upward extension of an atm I supported by the caine F, and on the other sido by
a plate, secured to the aim 7 by a screw in such a manner as to be readily
detachable for the purpose of removing the knife for sharpening. The aim
plate , are kept at the requisite distance apart to allow of the blade L sliding
easily between them, by means of a projection l', on the face of the plate 1,
and the blade L is slotted vertically as shown, to permit of the passage of this
projection, which is lengthened in the vertical ducction to serve as a guide for the
purpose of preventing the blade L fiom moving other wise thau vertically in its own
plane, the slot in the blade being made of sufficient length to allow of the upward
or downward movement of the latter. By being mounted, as described, upon the
work-plate carrier F, the knife L is caused to participate in the movements of
the work-plate J when the latter is reciprocated for the purpose of producing the
"barring" stitch and the blade is thus always maintained in position to rise
centrally of the width of the piesser foot clamp and work-plate apertures. The
arm carries a lug into which is screwed an adjustable screw stop 1, which serves
to limit the upward travel of the blade to suit any requied length of button hole,
by a lug 1, secured to the lower end of the blade stuking the screw stop
The button hole is cut when the machine is in position for "bairing" at the
commencement of the button hole, aud the cutting is effected by the blade L being
pushed up by the finger of the operator, the point of the blade easily piercing the
material held fast in the clamp and the oblique direction of the cutting edge of the
blade producing a diawing cut so that the blade encounters the loast possible
1esistance. The point or back of the knife is close up to the needle, as shewn in
Figures 3 and 9, so that the cut for the button hole, of whatever length, always
starts from the same point, the length of the button hole cut being determined by
the combined effect of the obliquity of the cutting edge and the amount of use of
the knife blade as controlled by the screw stop 12. The blade L will fall of its own
weight or a spring may be used to return it to its normal position.
The shuttle race N is cut away at the point n, Figures 23 and 9, to allow of the
knife L reaching close up to the needle, and the shuttle 1ace being attached to
the arm E. moves with that arm; thus the hole in the needle hole plate n¹
(Figure 9) and needle groove in the shuttle race or box N participate in the lateral
travel of the needle bar and require, therefore, only to be of sufficient width to
allow of the passage of the needle, whereas if the shuttle race were stationary the
needle hole and groove would have to be wide enough to allow for the traverse
movement of the needle.
M is a spring-pressed finger extending through the presser foot clamp K into
the cut button hole immediately in ear of the needle for the purpose of keeping
the button hole open and causing the fiayed theads fringing the edges of the hole
to be embraced by the stitches. The finger M is pivotally attached, by means of
the houzontal crank arm m and the vertical rod m, to the head A', of the machine
so as to be free to participate in the horizontal movements transversely of the button
hole of the presser foot clamp K within the aperture of which, shoulders formed
upon the finger, loosely fit, the finger M is also adapted to participate in the

page_text: vertical movements of the clamp K whether the latter be lifted bodily for the
purpose of insetting of lemoving the work, or (when being depressed) rocks, about
the pivot k, in adjusting itself to any inequalities in the thickness of the fabric to
be sewn.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, wo declare that what
we claim 18:
1. A button hole sewing machine wherein the needle bar guide continuously
receives uniform reciprocating motion in the hozontal direction at right angles
to the direction of feed, whilst the work-plate periodically receives reciprocating
motion concurrent with, and opposite in direction to, that of the needle bar guide,
the reciprocation of the work-plate being concurrent with the cessation of the
feed for the purpose of forming the "bairing" stitch, substantially as specified.
2 In a button hole sewing machine the combination of means for imparting
reciprocating motion to the needle bai guide and likewise imparting to the work-
plate reciprocating motion concurrent with, and opposite in direction to, that of
the needle bat guide, and of means whereby the reciprocation of the work-
plate is permitted only during the cessation of the feed, substantially as specified.
3. In a button hole sewing machine, a guillotine knife having a single oblique
cutting edge and fitted to slide in guides carried by the machine for cutting button
holes of variable lengths, substantially as described.
4. In the herein described button hole sewing machine, a guillotine knife having
a single obliquo cutting edge and fitted to slide in guides so supported as to be
movable with the work-plate when the latter 18 reciprocated for the purpose of
forming the "baring" stitch, the blade being thus always maintained in position
to rise centrally of the width of the presser foot clamp and work-plate apertures,
ats movement being limited by an adjustable stop for regulating the length of button
hole to be cut, substantially as shown and described.
5. In the herein described button hole sewing machine, the shuttlo box or race
and the reciprocating needle bai guide so combined and connected that they will
reciprocate as one, substantially as and for the purpose specified.
6 In a button hole sewing machine wherein the work-plate and work clamp
receive motion for feeding lengthways of the button hole and also reciprocating
motion transversely of the button hole, and wherein the hole is cut before being
sewn, a finger mounted upon the frame of the machine and extending through the
cut button hole, substantially as and for the purpose specified.
7. A button hole sewing machine constructed and operating substantially as
above described and shewn in the accompanying drawings.
Dated this 22nd day of October 1895.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.