Improvements in or relating to Sewing Machines.
Year: 1887

page_text: Date of Application, 16th Mar:, 1887
Complete Left, 16th Dec., 1887
Complete Accepted, 20th Jan., 1888
PROVISIONAL SPECIFICATION.
Improvements in or relating to Sewing Machines.
I, WILLIAM FAIRBURN HART, of the General Assurance Buildings, No. 1, East
Parade, Leeds, in the County of York, Patent Agent, do hereby declare the nature of
this invention which has been communicated to me from abroad by Charles Smith
Larrabee, of 8, Untermain Angle Frankfurt on Main Engineer and Benno Fischer, of
Cannstadt, but at present residing at Frankfurt on Main, in the German Empire,
Mechanician, to be as follows:-
This invention relates to sewing machines generally, but especially to those used in
the boot and shoe trades; and the invention comprises, first, improved mechanism for
forming a double lock stitch scam, consisting essentially of a free bobbin in com-
bination with a rotary loop or thread carrier, second, an improved device for tight-
ening the thread, and third, to improved feeding mechanism."
The invention is described applied to a machine having a vertical reciprocating
needle and provided with a work supporting horn, such as is used in the manufacture of
boots and shoes. Motion is conveyed to these parts in any convenient manner.
The mechanism for forming the double lock stitch seams comprises a vertical shaft
connected by bevel gearing with the main or driving shaft of the machine. On the
vertical shaft is provided a second bevel wheel which gears into a pinion or wheel
carried on the end of a horizontal shaft ;-these wheels are preferably in the ratio of
two to one, and arranged so that the horizontal shaft shall make two revolutions to
one of the vertical or main driving shaft. The horizontal or intermediate shaft
is connected by suitable gearing to a second horizontal shaft, one end of which is
preferably made square, and projects beyond its bearing. On this projecting end is
placed, so as to slide freely, the loop or thread carrier which is constructed as follows.
A sleeve, having a hole to fit the shape or contour of the projecting end of the second
horizontal shaft, and an annular groove in its periphery, provided at one end with
a projecting arm which is bent at its free end. This end is enlarged and extended
upwards to form a kind of catcher from which projects a pointed hook having a very
broad base. The loop or thread carrier revolves with its supporting shaft, but in
addition to the rotary motion an intermittent reciprocating motion is imparted to it

page_text: from a cam fixed to the vertical shaft, through a pivoted lever. One end of the
pivoted lever is provided with a runner or roller which is pressed by a spring against
the face of the cam, whilst the opposite end (also provided with a runner or roller)
engages with or works in the annular groove in the sleeve of the loop or thread
carrier. Below a plate, that supports several of the working parts of the machine, is
fixed a bracket between the cheeks of which, is placed a bobbin or spool, the said
bobbin being disconnected from the other parts. This bobbin upon which the thread
or yarn is wound consists of two arched circular metal plates connected together at a
suitable distance apart (at their centres) by a spindle. The spool or bobbin is clamped
in position against one of the checks of the bracket by one end of a bolt (carried in
On the
suitable bearings in or on the bracket) which is surrounded by a spring.
opposite end of the bolt is an inclined disc which is acted upon by a wedge shaped
ended lever this end is also bifurcated so as to slide over the bolt. Motion is conveyed
to the bifurcated wedge shaped lever from a cam disc on the driving shaft of the
machine through a pivoted lever; one end of which is pressed by means of a spring
against and acted upon by a number of projections or noses formed on the cam disc,
whilst the other end is connected to the wedge shaped ended lever. When the
wedge shaped ended lever is moved towards the bolt, the action of the wedge shaped
end on the incline will cause the bolt to slide in its supports whereby the pressure of
the bolt upon the bobbin is removed so that the latter is free to rotate. The loop or
thread carrier may be arranged to work above the material being operated upon. The
operation of the above described mechanism is as follows-The hooked needle of the
machine pierces through the fabric to be sewn, and in its ascending motion carries
with it the thread, which forms a small loop around the hook of the needle. The loop
or thread carrier now approaches and by means of the catcher pushes aside the thread
which is between the bobbin and the fabric, and by which the last stitch has been
formed, so that the point of the hook (on the catcher)-which latter has now approached
the needle, can, without hinderance, enter the thread loop formed by the hook of the
needle. During the further rotation, the carrier takes the loop from the needle, and
carries the said loop around the bobbin, which at this moment is freed from all
When this has been
pressure by the displacement of the wedge shaped ended lever.
effected, the carrier shifts from right to left, the loop being stripped of the hook (of
the catcher) and the thread is firmly tightened from below. As regards the rotary
motion of the loop carrier it may be observed that it makes two revolutions during
one lift of the needle, by reason of the proportion in the size of the bevel gearing,
these motions being utilized on the one hand for transporting the loop over the bobbin,
in the described manner, and, on the other hand, in combination with the laterally
displacing motion, for pushing aside the thread forming the last stitch, and taking off
the loop from the hook of the catcher, and also for making room for the needle again
to effect the succeeding descent. Moreover, the quick motion of the carrier admits of
a slower motion of the needle, whereby a more exact operation of the device is
obtained.
The improved thread tightening mechanism comprises a cam disc which is fixed to
the driving shaft of the machine so as to act upon one end of an angle or bell
cranked lever whilst the other end is coupled by means of a connecting rod or lever to
a pivotted or double armed lever. One end of this double armed lever is provided
with a friction roller which engages with or works in an annular groove in a sleeve
which slides freely on a vertical shaft under the horn of the machine. On any motion
being given to the double armed lever by the cam disc, such motion is at once trans-
mitted by a rod to a double ended lever pivoted to a convenient part of the machine.
To one end of this double ended lever is connected a rod carrying at its upper end a
small roller round which the thread is conducted from one or more rollers (fixed to the
horn) as it passes from the stationary bobbin on the horn to the operating point.
When the sleeve is moved upwards by the action of the cam disc upon the driving
shaft, the end of the double ended lever is depressed which draws down the rod and
roller thereby tightening the thread.
The feeding mechanism constructed according to this invention consists of a guide

page_text: bar pivoted to the machine. One end of which engages with a lateral curved path
formed in a cam disc on the driving shaft of the machine, whilst to the opposite or
free end is fixed a pawl which engages with a rack attached by suitable bolts or studs
(so as to slide freely) to the guide bar. In the rack are also provided suitable slot
holes through which the bolts or studs pass so as to permit of the movement of these
parts relatively to each other in the longitudinal direction of the bar. As soon as the
bar by reason of its connection with the path of the cam is pressed downwards on one
side, the other part beyond the fulcrum will with the rack move upwards whereby the
presser foot of the machine which is connected to an inclined slot hole in the rack by
means of a sliding bolt or stud will be raised.-When fabrics or material of
different thicknesses are required to be sewn, the stuff presser will move upwards
or downwards in correspondence therewith, according as thick or thin material comes
under the same, this motion is transmitted to the rack, for the reason that the presser
is connected by the sliding bolt (which works in the inclined slot hole) with the rack,
which is thus displaced laterally on the guide bar. With thick material the sliding
bolt will be higher in the inclined slot hole than with thin material. The pawl fixed
to the guide bar and which by its engagement with the rack prevents the automatic
displacement of the latter, is disengaged by a finger (secured to a shaft carried in or
by suitable bearings on the machine) as soon as the feed dog has advanced the
material the length of a stitch, so that the presser again passes at once on to the
fabric and occupies the position determined by the thickness of the same. The feed
dog is pushed forwards and backwards by a lever which is connected at one end with
the feed dog by a link whilst its other engages, with a circumferential inclined path
formed in the herein before mentioned cam disc. In order to prevent the feeding
mechanism from being lifted whilst the needle is being moved upwards a finger or
projection attached to a rod or other suitable part is made to bear upon the rack
during this motion of the needle.
Dand have of Manal 1007
W. FAIRBURN HART.

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Sewing Machines.
I, WILLIAM FAIRBURN HART, of the General Assurance Buildings, No. 1, East
Parade Leeds, in the County of York, Patent Agent, (a communication to me from
abroad by Charles Smith Larrabee, of 8, Untermain Anlage, Frankfurt on Main,
Engineer, and Benno Fischer, of Cannstadt, but at present residing at Frankfurt on
Main, in the Empire of Germany, Mechanician) 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 sewing machines generally, but especially to those used in
the boot and shoe trades. The invention comprises, first, improved mechanism for
forming a lock stitch seam ("doppel step stitch") consisting essentially of a free
bobbin in combination with a rotary loop or thread carrier; second, an improved
device for tightening the thread; and third, improved feeding mechanism.
The invention is shown applied to a machine of the Blake Sole Sewing type, having
a vertical reciprocating needle and provided with a work supporting horn, such as is used
in the manufacture of boots and shoes. Motion being conveyed to these parts in any
convenient and well known manner.
In the drawings hereunto annexed
Fig. 1. is a side view of a sewing machine of the Blake type to which these
improvements are applied.
Fig. 2. a plan of mechanism for forming the lock stitch scam, and
Fig. 3. a front view of same.
Figs. 4 to 9 are views of details of the said mechanism.
Figs. 10, 11 and 12 are respectively a side elevation, plan, and front elevation of
the feed mechanism.
Figs. 13, 14, and 15 are views showing the application of a slightly modified form
of "take up arrangement.
In order to obtain greater clearness, Figs. 2 to 12 and 14 and 15 are drawn to a
larger scale than Figs. I and 13.
A is the main driving shaft of the machine and is mounted in suitable bearings A¹
formed on the framework A2. On the end of the shaft A is provided a hand or fly
wheel A³ or when the machine is driven by power a pulley. E is the needle mounted in
a suitable bar E¹ to which a vertical reciprocating motion is imparted from an
eccentric E on shaft A through eccentric strap E³, lever C fulcrumed at D and
connecting rod E. All the above described parts may be of the same construction,
and may operate in a similar manner to those of a Blake Sole Sewing machine.
The mechanism for forming the lock stitch ("doppel step stitch") seam comprises
a vertical shaft F connected by bevel gear wheels G G¹ with the main driving shaft A
and rotated by the latter. This motion of the shaft F is transmitted by the bevel gear
wheels H H¹ to the shaft J and from it by another pair of bevel gear wheels KK to
the shaft L which supports the loop or thread carrier N. The bevel wheels H H¹ are
in the ratio of two to one, or three to one, or any desired ratio, so that the shaft J

page_text: makes two, three, or more revolutions to one of A. The shaft L.is made to protrude
from its bearing M, and this part of the shaft is square (as shown at Figs. 2 and 3)
and carries the loop or thread carrier N so as to slide freely thereon.
The movement of the loop or thread carrier is effected by a cam O secured upon the
vertical shaft F and against which the roller or runner R upon one end of the lever Q,
pivoted upon the stud P, is pressed by the spring S as shown at Fig. 2. The other
end of the lever Q is provided with a roller or runner T which engages with an
annular groove a' in the loop carrier N so that the latter in making two, three, or
more revolutions during the corresponding motion of the lever Q, caused by the
cam O, is displaced upon the shaft L from left to right or inversely.
The construction of the carrier itself is illustrated at Fig. 5. which is a perspective
view as seen from the side.
a is a sleeve provided with an annular groove a¹, and having a square opening b
adapted to fit the square part of the shaft Land to slide thereon. c is an arm made
in one piece with the sleeve a and bent at its free end. This free end is enlarged and
extended upwards to form a kind of catcher d from which projects a pointed hook e
having a very broad base.
Upon the driving shaft A is placed the cam disc U, upon the periphery of which
are formed the projections or noses as shown at Figs. 2 and 3. is a double ended
lever which is pivoted at i to the framework and provided at its upper end
with a friction runner or roller which is pressed against the cam disc U by a
spring, whilst the other end of the lever V is jointed to a horizontal rod or
lever having its free end formed in the shape of a wedge and bifurcated
for the purposes hereafter described. By keeping the friction roller & against the cam
disc U as described, as the disc rotates one of the projections passes under the friction
roller whereby the horizontal lever V' is moved in the direction of arrow 1 shown
in Fig. 2.
Z is a bobbin or spool arranged between the cheeks 1, m of the bracket X, which is
placed below a plate W, the said bobbin being disconnected from the other parts.
This bobbin upon which the yarn or thread is wound consists, as will be seen from
Fig. 4, which shows it in elevation and section, of two arched or concavo-convex
circular metal plates or discs which are connected together at their centres by a
spindle. The two concavo-convex plates or discs are not arranged close against each
other but have a slit between them through which the thread passes.
22
The
Y is a bolt which is supported by and is moveable in the bracket X. This bolt Y
is surrounded by a spring n by which it is pressed at one end against the bobbin Z
so that the latter is clamped between the bolt Y and cheek and cannot move.
other end of the bolt Y protrudes from the bracket X and is provided with the
disc 02 having an incline on one side which is acted upon by the wedge shape end v
of lever V which is also bifurcated so as to slide over the bolt Y. The required
sliding motion is given to the lever V1 from cam disc U through double ended
lever V as herein before described. When the lever V₁ moves in the direction
indicated by the arrow 1 in Fig. 2 the action of the wedge shape end on the
inclined disc 02 will cause the bolt Y to slide in its supports or bearings
in the direction indicated by arrow 2, whereby the pressure of the said bolt upon the
bobbin Z is removed so that the latter is free to rotate.
The operation of the above described mechanism is as follows:
-
The hooked needle E pierces through the material being operated upon, and in its
ascending motion carries with it the thread (which has been placed in the hooked
portion of the needle by means of a whirl, not shown in the drawings, such as
is commonly used on a Blake Sole Sewing machine, and to which motion is conveyed
in the ordinary manner. As the whirl and means for giving motion thereto are old
and well known parts of the Blake Sole Sewing machine they have not been shown in
the drawings to avoid confusing them with another part of this invention) which
forms a small loop around the hook of the needle as shown at Figs. 6 and 7. The
carrier N now approaches and by means of the catcher d pushes aside the thread
which is between the bobbin and the material, and by which the last stitch has been

page_text: formed, so that the point of the hook e which latter has now approached the needle can
without hindrance, enter the thread loop formed by the hook of the needle. During
its further rotation, the carrier N takes the loop from the needle, as shown at Fig. 8. and
carries the said loop around the bobbin Z, as shown at Fig. 9, which at this moment is
freed from all pressure by the displacement of the lever and bolt Y. When this
has been effected the carrier shifts from right to left, the loop being thereby stripped
off the hook e and the thread tightened from below. In commencing to form a stitch
the end of the thread is drawn from the bobbin Z to the surface of the material and
held by the finger of the operator's left hand until the needle has drawn up a loop of
thread from the lower spool, and a stitch has been formed as above described. As
regards the rotary motion of the loop carrier N it may be observed that the latter
makes two or more revolutions during one lift of the needle E by reason of the
proportion in the size of the bevel wheels H H', these motions being utilized on the
one hand for transporting the loop over the bobbin Z (in one revolution) in the
described manner, and on the other hand, in combination with the laterally displacing
motion, for pushing aside the thread forming the last stitch and taking off the loop
from the hook e and also for making room for the needle again to effect the succeeding
descent. Moreover, the quick motion of the carrier admits of a slower motion of the
needle, whereby more time is gained for pulling in the loop and as a consequence a
more exact operation of the device as a whole is obtained.
The improved thread tightening mechanism is shown at Fig. 1, and comprises a
cam disc on the driving shaft A which acts upon the jointed levers A', B¹, C. A is
an angle or bell crank lever and has its fulcrum at whilst the lever O₁ is double
armed, and has its fulcrum at D'. The friction roller G is mounted on one end of the
lever and works in an annular groove formed in the sleeve F¹ which is moveable
upon the vertical shaft E, and the up and down motion of which is transmitted by the
rod H2 to the lever K2 which is capable of turning upon the point or fulcrum Jon
the horn U¹.
The lever K³ is connected by a joint with the rod L' at the upper end of which is a
small roller M' around which the thread O' is conducted from the roller P¹ (the
latter being fixed and capable of turning on a stud within the horn U¹) or from the
bobbin Q to the operating point. When the sleeve For rod His caused to move in
the direction of arrow 3 by the cam disc upon the driving shaft A in combination
with the levers A, B, and C, the rod L' connected by a joint with the lever K³
makes a descending movement in the direction of arrow 4 so that the thread O' is
thereby tightened.
At Figs. 13, 14, and 15 is shown a slightly modified arrangement of mechanism for
tightening up the stitch, in which movement is given to a rod H² from an eccentric
cam on shaft A through bell crank lever A1 connecting rod B¹ and double ended
lever C. The rod H is made to work in the horn U¹ as shown, and on the upper end
of the rod is mounted and fixed an inverted cone which is preferably made of
hardened steel. Upon the horizontal part of the horn "U₁ of the machine is placed the
lever K fulcrumed at J' to the horn and armed at r with a runner upon which the
inverted cone g operates. To the horn is also fulcrumed at J a lever L' carrying a
thread pulley or guide P¹. The levers K² and I are connected together by means
of a connecting rod K³ at p³ and p. In the angle of the horn are further fixed the
rollers M', M² over which the thread passes from the spool or bobbin Q (also mounted
on the horn).
This devices operates in the following manner-From the spool Q₁ the thread
is carried around roller M² thence to roller P¹ on lever L' then back to roller M'
and from thence up through the incline of the horn to the work. The loop
having been drawn up through the material by the needle as herein described,
and thrown by the thread carrier N over the upper spool Z, a downward
movement is given to the inverted cone g on rod H2 from the cam
on shaft
A through levers A and C and rod B₁, which presses the cone against the
roller thereby forcing back the lever K which movement of the lever K2 also draws
back with it the lever L' by means of the connecting link K³. The fulcrum of the

page_text: lever being on its outer end, and the link K³ being jointed to the lever near to the
fulcrum point, the movement of the lever L' at its free end is considerable so as to
draw a large amount of thread with it. The slack thread which would be drawn by
this movement is that forming the loose loop which is now being drawn in, for the
other end of the thread is on the spool and it requires a greater tension to pull it off
the spool than it does to pull in the loop. After the loop is drawn in, the cone is
given an upward movement which brings the levers back to their original position and
during this movement the hook descends and draws up more thread from the spool,
and at the same time takes up the loose thread caused by the forward movement of the
levers. It will be readily seen that in the arrangement just described the levers are
arranged to draw in the thread in a horizontal direction for tightening purposes,
instead of vertically as shown at Fig. 1.
The feed mechanism constructed according to this invention is shown at Figs. 1, 10,
11 and 12 and consists essentially of the guide bar g', the pawl, the rack having
the slots and d³ provided therein, the finger n' connected with the lever v¹, the
cam 2 acting upon the rack, the stuff presser foot a³ and feed dog T. The motion of
these parts is effected by the cam disc upon the driving shaft A which disc is
provided with a lateral curved path and the circumferential inclined path k³ with
the former of which the roller m¹ on the guide bar is engaged.
To the guide bar g' which is pivoted at is connected the rack d' by means of the
slots and slide bolts therein, in such a manner as to enable the movements of these
two parts relatively to each other in the longitudinal direction of the bar g¹. As soon
as the bar g, by reason of its connection with the path of the cam k is pressed
downwards by the roller m² on one side, the other part beyond the fulcrum will,
with the rack d¹ move upwards, whereby the presser at which is connected with
the rack by the sliding bolt in the slot 3 of the said rack is likewise raised.
The part of the rack which forms the loop or inclined slot hole d³ is bent at an
angle, as illustrated in Figures 1 and 10. When materials of different thicknesses are
sewn, the presser a will move upwards or downwards in correspondence therewith,
according as thick or thin material comes under the same, this motion being trans-
mitted to the rack for the reason that the presser at is connected by the sliding
bolt and the loop with the aforesaid rack which is thus displaced laterally on
the guide bar g'. With thick material, the sliding bolt will therefore be higher in
the loop d³ than with thin material.
The pawl ¹ fixed to the guide bar g' and which by its engagement with the
rack prevents the automatic displacement of the latter, is disengaged by the
finger n¹ secured to the shaft (carried in or by suitable bearings on the machine)
as soon as the feed dog T has advanced the material the length of a stitch so
that the presser again passes at once on to the material and occupies the position
determined by the thickness of the same. The feed dog T is pushed forwards and
backwards by the lever which is connected at one end with the said feed dog by the
link R whilst its other end engages with the curved path of the cam disc
In order to prevent the mechanism from being lifted whilst the needle is being
moved upwards, the finger p¹ on the rod p is made to bear upon the rack d¹.
Other parts of the machine not shown or described may be of a similar description
to that usually employed on a Blake Sole Sewing machine.
Having now particularly described and ascertained the nature of the said
Invention (as communicated to me by my said Foreign Correspondents) and in what
manner the same is to be performed, I declare that what I claim is
1. The manufacture and use of a sewing machine such as herein described, with a
rotating and intermittent reciprocating loop carrier such as N (and parts connected
therewith) working above the material, and operating in conjunction with a stationary
bobbin or spool (placed under the material), a vertical reciprocating hooked needle,
and mechanism for tightening the thread for forming a lock stitch seam, substantially
as described.

page_text: 2. In a sewing machine such as herein described the combination of a hooked
needle such as E, with a spool or bobbin such as Z, the rotary loop carrier such as N,
and means for operating the same, all arranged substantially as described and illus-
trated for forming a lock stitch seam.
3. In a sewing machine, a spool or bobbin such as Z and parts for holding it in
position so arranged that during the motion of the machine it is alternately released
so that it can rotate to allow the passage of the loop and afterwards be clamped for
tightening the thread, substantially as above set forth.
4. In a sewing machine, in combination with a vertical reciprocating needle, a
loop carrier such as N so arranged that during one lift of the needle it will make two
or more revolutions, such revolutions of the carrier in combination with the lateral
motion of the same upon its supporting shaft L being employed to push aside the
thread forming the last stitch, to carry the loop over the bobbin, to take off the loop
from the hook e, and to make room for the needle to again perform the succeeding
downward motion substantially as described and illustrated at Figs. 1 to 9.
5. In a sewing machine, the mechanism by which the thread is tightened after
the loop has been laid round a bobbin or spool, such as Z, by a carrier, such as N, the
said mechanism comprising the combination of the levers A, B, C, K², and K³
operated by a cam disc arranged upon the driving shaft A, the sleeve F1 moveably
arranged upon the shaft E and having the rod H' attached thereto, the rod I'
provided at its free end with the roller M¹ and the roller P¹ turning upon a stud
secured to the horn U all arranged and operating substantially as described.
6. In a sewing machine, the feed mechanism capable of being automatically adjusted
in accordance with the varying thicknesses of the material to be sewn, so as always to
operate in the same manner without regard to the thickness of material operated upon,
said mechanism consisting of the guide bar g', the pawl, the rack & provided with
slot holes d² and d³, the rocking shaft provided with the finger n¹, the finger pl
arranged upon the rod p, the presser a* and feed dog T acted upon by the lever ² in
combination with the cam disc upon the driving shaft A of the machine, all
arranged and operating together substantially as above described and illustrated at
Figs. 1, 10, 11 and 12.
7. In a sewing machine such as herein described, the method of forming
a lock
stitch seam by mechanism, consisting essentially in the use of a bobbin such as Z, a
hooked needle such as E, a carrier such as N, a catcher such as d to press aside the
thread, a hook such as e which throws the loop over the bobbin Z and disengaging
mechanism to release the bobbin so that it is free whilst the thread is being thrown
over the same, in combination with the thread tightening device and feeding
mechanism substantially as herein set forth and illustrated.
8. The combination of the various parts forming the sewing machine as a whole
constructed and arranged substantially as herein set forth and illustrated.
Dated this Fourteenth day of December 1887.
W. FAIRBURN-HART.