Improvements in Buttonhole Sewing Machines
Year: 1896

page_text: Improvements in Buttonhole Sewing Machines,
I, WILLIAM MOHT, of 125 North Montrose Street, in the City of Glasgow, Engineer,
do hereby declare the nature of this Invention to be as follows:-
This Invention has for its object to provide a sewing machine for simultaneously
overseaming both sides of a button hole and automatically barring the ends thereof.
For that purpose I employ a sewing machine having two needles carried by the
reciprocating needle bar and I impart to the needle bar lateral movements, such as
are applied in single needle machines to produce zig-zag stitches, whereby the needles
descend alternately through the fabric and through the cut button hole so that each
needle is used to overseam one edge of the button hole. A shuttle or looper for each
needle is carried in a shuttle race below, to which endwise movement is imparted
corresponding to the lateral movement of the needle har. The fabric is fed in the
line of the button hole by feeding devices hereinafter referred to, and at each end of
the button hole the extent of lateral movement of the needle bar is varied
automatically in order to cause the needles to stitch across the button hole to bar the ends
whilst on the completion of the barring operation the machine automatically stops.
The machine is of the ordinary form with bed plate and overhanging arm which
latter carries the usual shaft on one end of which are mounted the usual fast and loose
belt pulleys. The stop motion for the machine is of the ordinary kind and carries a belt
shifter, the stop motion acting to throw the driving band on to the loose pulley while the
fast wheel is braked up. The stop motion lever engages at its lower end with a trigger
actuated by a kicker pin on a feed cam carried on a spindle beneath the bed plate and
which is rotated by a ratchet wheel. The ratchet wheel is actuated through a connecting
rod, radius lever and pawl from an eccentric secured on an oscillating rock shaft, said
eccentric acting on a roller fixed in the side of the connecting rod to impart the
necessary feed movement to the ratchet wheel. The shuttle shaft is carried in
suitable bearings beneath the bed plate in such a way that it can receive endwise
motion from a block in a rocking slot bar carried on the arm of the machine, the
block being connected by links and levers to a block secured on the shuttle shaft.
This endwise motion is such that two shuttles which are provided and carried in the
shifting shuttle race, move in unison with the overseaming movement of the needle
bar which receives its end movement from a second block on the rocking slot bar,
this block acting through a link to impart motion to the usual rocking frame carrying
the needle bar. This rocking slot bar receives its motion from a cam on a short
spindle carried at right angles to the arm shaft and is driven therefrom by bevel
gearing.
The knife bar which is carried up through the head of the arm is surmounted by
a button which is pressed downwards by the hand to cut the hole. This bar has a
twist groove cut in it, into which the point of a screw secured in the head of the
machine engages. A split tongue fastened to the bar and sliding in a slot formed
in the head holds the knife firmly while the cutting is being performed. A spiral
spring surrounding the bar carries it up again when the hand pressure is released,

page_text: and in rising the screw engages the twisting groove and acts upon said groove to turn
the knife clear of the needle bar during the stitching of the button bole.
The needle bar carries two needles and the action of the machine in conjunction
with these needles is such as to make a button hole as hereinafter described.
The stitch for the overseaming of the button hole represents the gauge or throw of
the needle but the barring stitches on the ends of the hole and which are greater are
obtained by automatically increasing the overseaming throw of the needles and
shuttles, so that the needles cross the hole and tie the ends in a barred or overlapping
stitch.
This automatic change from barring to overseaming necessary for the proper
production of the button hole is obtained by the ratchet motion on the machine arm.
This motion is designed to control a gear crank dise. By giving this gear crank dise
a half revolution the blocks in the rocking slot bar for imparting the endwise motion
to the shuttle shaft and to the needle bar will approach the centre or come toward
each other.
When the other half revolution of the gear crank disc is performed the blocks will
recede from the centre into their first position. This intermittent movement of the
blocks to and from the centre will cause the needles to have a short overseaming
stitch and a long overseaming stitch and by suitably controlling this change in
these blocks the button-hole desired is produced. The ratchet motion actuating the
crank disc consists of a ratchet wheel carried loosely on a spindle and having secured
to its face a disc with two notches in it. On the same spindle a second ratchet wheel
is loosely carried to whose face a pinion wheel is fixed which gears through pinions
on a separate spindle with a pinion on whose face the crank disc before mentioned is
secured. The ratchet wheels are turned by pawls secured on a radius lever connected
by a link to the rocking slot bar, the main pawl which actuates the ratchet wheel on
whose face the notched disc is secured being prevented from turning more than one tooth
at a time by a guard placed round a portion of this ratchet wheel the other pawl being
prevented from turning its ratchet wheel until by the revolution of the notched disc
the pawl can engage, by entering the notch, with its ratchet wheel....The pinion
secured upon this latter ratchet wheel then acts through its intermediat egearing on
the crank disc and turns said disc so as to bring the blocks in the rocking slot bar
towards the crank disc which forms the centre of the rocking bar to make the
overseaming or short stitch or from this centre to make the barring or long stitch
alternately at each semi-revolution of the crank disc.. Thus when the pawl for
actuating the ratchet wheel on whose face the pinion wheel is fixed engages either
of the notches in the notched disc the change from the ordinary overseam or short
stitch to the barring or long stitch and the change from the barring to the overseam
stitch takes place. This notched wheel is termed the timing wheel. A pin fixed on
the feed cam throws the stop motion into action to stop the machine when the
stitching has reached the middle of the barring operation. The operation of the
ratchet motion is as follows:-The machine being started, three or four barring
stitches are formed, and by this time the main pawl has fed round the ratchet wheel
to which the timing wheel is secured so far that the second pawl by reason of its being
opposite one of the notches in the timing wheel can drop into action with its ratchet
wheel and so impart to the crank disc by means of the intermediate gearing one half
of a revolution. This half revolution causes the approach of the blocks and the
ordinary overseaming of the hole takes place. The main pawl is acting slowly feeding
round the timing wheel until the second pawl can drop into one of the notches and
gear with its ratchet wheel thereby performing another half revolution bringing it
back to its original position and causing the blocks to recede from the centre and make
the three or four barring stitches required. As soon as this number of stitches is
made the stop motion is actuated by the pin on the feed cam coming into contact
with the trigger before mentioned and the machine is stopped, the button hole being
finished.
The presser bar is of the ordinary hinged travelling type and the presser foot is also
hinged and fitted with a spring. The presser bar clamps the work on the feed plate

page_text: which receives its feed motion from the feed cam before mentioned on which the pin
for actuating the stop motion is secured, acting through a lever on a roller affixed to the
bottom side of the feed plate. The needle plate is raised in the centre in order that
the goods when clamped down by the presser foot may be drawn tightly and at the
same time held in a way calculated to produce the best possible button-hole.
Dated this 30th day of Inly 1896
I, WILLIAM MORT, of 125 North Montrose Street, in the City of Glasgow, 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 has for its object to provide a sewing machine for simultaneously
overseaming both sides of a button hole and automatically barring the ends thereof.
For that purpose I employ a sewing machine having two needles carried by the
reciprocating needle bar and I impart to the needle bar lateral movements, such as
are applied in single needle machines to produce zig-zag stitches, whereby the needles
descend alternately through the fabric and through the cut button hole so that each
needle is used to overseam one edge of the button hole. A shuttle or looper for each
needle is carried in a shuttle race below, to which endwise movement is imparted
corresponding to the lateral movement of the needle bar. The fabric is fed in the
line of the button hole by feeding devices hereinafter referred to, and at each end of
the button hole the extent of lateral movement of the needle bar is varied auto-
matically in order to cause the needles to stitch across the button hole to bar the ends
whilst on the completion of the button hole the machine automatically stops.
The invention is illustrated by the accompanying drawings, Fig. 1 being a side
elevation, Fig. 2 a plan with the arm removed; Fig. 3 an end elevation with the face
plate removed and Fig. 4 a plan of the head of the machine. Fig. 5 is a plan of the
ratchet movements hereinafter particularly referred to, and Fig. 6 is a detail of said
ratchet movements. Fig. 7 is a view shewing the manner of stitching and barring
the button hole as performed by the improved inachine.
As shewn the machine is of the ordinary form with bed plate B and overhanging
arm A which latter carries the usual shaft (not shewn) on one end of which are
mounted the usual fast and loose belt pulleys C, C. A stop motion lever D of the
ordinary kind is provided and carries a belt shifter D', the stop motion acting to
throw the driving band on to the loose pulley C¹ while the fast wheel is braked up.
The stop notion lever D engages at its lower end with a trigger E actuated by a
kicker pin F on a feed cam G carried on a stud beneath the bed plate said cain being
rotated by a ratchet wheel G¹. The ratchet wheel G¹ is actuated through a connecting
rod H, radius lever H¹ and pawl H² from an eccentric or cam H secured on an
oscillating rock shaft H, said eccentric acting on a roller I fixed in the side of the
connecting rod H to impart the necessary feed movement to the ratchet wheel G¹.
A shuttle shaft J is carried in suitable bearings beneath the bed plate B in such a
way that it can receive endwise notion through connecting rods K1, K2, K³, from a
block K in a rocking slot bar L carried on the arm A of the machine, the block K
being connected through these links and levers to a block K' secured on the shuttle
shaft J. This endwise motion is such that two shuttles which are provided and

page_text: carried in a shifting shuttle race M, move in unison with the overseaming movement of
a needle bar M¹ which receives its end movement from a second block K on the rocking
slot bar L, this block K³ acting through a link Ke to impart motion to the usual
rocking frame K7 carrying the needle, bar M'. In lieu of the arrangement of the
shuttles shewn any other arrangement or other type of shuttles or loopers may be
used which have endwise motion imparted to them corresponding to the motion of
the needles as described. This rocking slot bar L receives its motion from a cam or
eccentric on a stud 0 carried at right angles to the arm shaft and is driven therefrom
by bevel gearing not shewn on the drawing.
A knife bar P which is carried up through the head of the arm A is surmounted by
a button P¹ which is pressed downwards by the hand to cut the hole. This bar has a
twist or scroll groove P2 cut in it, into which the point of a screw Q secured in the
head of the machine engages. A split tongue R fastened to the bar P and sliding in
a slot S formed in the head of the machine holds the knife P3 firmly while the
cutting is being performed. A spiral spring T surrounding the bar carries it up
again when the hand pressure is released, and in rising the screw Q engages the
twisting groove P2 and acts upon said groove to turn the knife P3 clear of the needle
bar during the stitching of the button hole.
The needle bar M¹ carries two needles and the action of the machine in conjunction
with these needles is such as to make a button hole as hereinafter described, and
illustrated by Fig. 7.
The cross stitch for the overseaming of the button hole is determined by the gauge
or throw of the needle but the barring stitches on the ends of the hole and which are
greater are obtained by automatically increasing the overseaming throw of the needles
and shuttles, so that the needles cross the hole and tie the ends in a barred or over-
lapping stitch.
This automatic change from barring to overseaming necessary for the proper
production of the button hole is obtained by the ratchet motion on the machine arm as
shewn particularly at Figs. 1 and 5. This motion is designed to control eccentrics N', N,
formed on a shaft N as shewn. By giving these eccentrics discs a half
revolution the blocks K, Ko, in the rocking slot bar L for imparting the endwise motion
to the shuttle shaft J and to the needle bar M¹ will approach the centre of the shaft N
or come toward each other. When the other half revolution of the eccentrics is
performed the blocks K, K5, will recede from the centre of the shaft N into their first
position. This intermittent movement of the blocks K, K³, to and from the centre
will cause the needles to have a short overseaming stitch and a long overseaming stitch
and by suitably controlling this change in these blocks K, K, the button-hole desired and
illustrated by Fig. 7 is produced. The ratchet motion actuating the eccentrica N¹, N,
consists of a ratchet wheel Ulcarried loosely on a spindle U and having secured to its face
a dise U with two notches u in it. On the same spindle U a second ratchet wheel U is
loosely carried to whose face a pinion wheel Uisfixed which gears through pinions U³, U,
on a separate stud U7 with a pinion U8 on whose face the eccentrics N1, N2, may
be secured. The ratchet wheels U1, U³, are turned by pawls c, b, secured on a radius
lever V connected by a link V to the rocking slot bar L, the main pawl c which
actuates the ratchet wheel U on whose face the notched disc U2 is secured being
prevented from turning more than one tooth at a time by a guard d placed around a
portion of the ratchet wheel U the other pawl b being prevented from turning its
ratchet wheel Us until by the revolution of the notched disc U2 the pawl can engage
with its ratchet wheel Us by entering one of the notches u. The pinion U secured
upon this latter ratchet wheel Us then acts through its intermediate gearing Us, U, U,
on the shaft N and turns said eccentrics N', N2, so as to bring the blocks K, K', in
the rocking slot bar L towards the centre of the shaft N which forms the centre
of the rocking bar L to make the overseaming or short stitch or from this centre to
make the barring or long stitch alternately at each semi-revolution of the eccentrics.
Thus when the pawl b for actuating the ratchet wheel U on whose face the pinion
wheel U is fixed engages either of the notches u in the notched disc U the change
from the ordinary overseam or short stitch e to the barring or long stitch as
с

page_text: shewn at Fig. 7 and the change from the barring to the short overseam stitch takes
place.
The pin F fixed on the feed cam G throws the stop motion into action at the end
of the button hole to stop the machine when the stitching has reached the middle of
the barring operation, that is to say, if the disc U2 is cut to give twelve barring
stitches the stop motion comes into action after six of these have been performed thus
leaving six barring stitches to form the bar at the commencement of the next hole.
The operation of the ratchet motion is as follows: The machine being started, and
say six barring stitches / formed, by this time the main pawl e has fed round the
ratchet wheel U¹ to which the disc U2 is secured so far that the second pawl b by
reason of its being opposite one of the notches u in the disc U can drop into action
with its ratchet wheel Us and so impart to the eccentrics N1, N2, by means of the
intermediate gearing one half of a revolution, This half revolution causes the
approach of the blocks K, K, and the ordinary overseaming of the hole takes place.
The main pawl c is acting slowly, feeding round the disc U2 until the second pawl b
can drop into one of the notches u and gear with its ratchet wheel U³ thereby
performing another half revolution bringing it back to its original position and
causing the blocks K, K', to recede from the centre and make the six barring stitches f
required. As soon as this number of stitches is made the stop motion D is actuated.
by the pin F on the feed cam G coming into contact with the trigger E before
mentioned and the machine is stopped, the button hole being finished.
The presser bar I is of the ordinary hinged travelling type and the presser foot i
is also hinged and fitted with a spring it. The presser bar 1 clamps the work on the
feed plate which receives its feed motion from the feed cam G before mentioned on
which the pin F for actuating the stop motion D is secured, acting through a lever A on a
pin joint- k affixed to the bottom side of the feed plate j said lever being carried on a
movable pivot k which permits the feed to be lengthened or shortened. The needle
plate I may be raised in the centre as shewn at Figure 8, in order that the goods when
clamped down by the presser foot i may be drawn tightly and at the same time held in
a way calculated to produce the best possible button-hole, or the raised part of the
needle plate may be dispensed with as shewn at Figs. 1, 2 and 3.
Having now particularly described and ascertained the nature of my said Invention,
and in what manner the same is to be performed, I declare that what I claim is :-
1. A sewing machine adapted to form straight button holes by stitching with two
needles and two shuttles or loopers having an overseaming throw, each needle serving
to overseam one side of the button hole.
2. A twin needle button hole sewing machine in which the needle bar and shuttles
or loopers have imparted to them a lateral movement across the line of feed
substantially as and for the purpose set forth.
3. The combination with a twin needle button hole sewing machine in which the
needle bar and shuttles or loopers have a lateral or overseaming throw of mechanism
such as described for automatically effecting alteration of such throw at each end of
the button hole.
4. The combination with a twin needle and twin shuttle button hole sewing
machine in which the needle bar and shuttles or loopers have a lateral or overseaming
throw, of mechanism for automatically effecting alteration of such throw and means
for stopping the machine when the button hole has been sewn and barred substantially
as described.
5. In an overseaming sewing machine the combination of the ratchets UI, U³,
gear wheels U, U, U, U, eccentrics N¹, N, and connections for automatically
changing the overseaming throw of the needle bar substantially as described.
6. In a sewing machine the combination of the travelling presser, slide plate i,
motion bar and cam g for producing a short feed of predetermined length substantially
as described.
7. In a button hole sewing machine a knife carrier and bar having a turning or

page_text: twisting movement imparted to it in its ascent and descent substantially as and for
the purpose set forth.
8. A sewing machine whose several parts are constructed, arranged or combined
as described and adapted for simultaneously overseaming both sides of a button hole
and automatically barring the ends thereof.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62 Saint Vincent Street, Glasgow, Agent for the Applicant.