Improvements in Sewing Machines.
Year: 1889

page_text: Date of Application,- 10th May, 1889
Complete Specification Left, 10th Feb., 1390-Accepted, 15th Mar., 1890
PROVISIONAL SPECIFICATION.
Improvements in Sewing Machines.
We, ALEXANDER ANDERSON, Manager, and ROBERT ANDREW FERGUSON POLLOCK,
Mechanic, both of the Singer Manufacturing Company's Works, Kilbowie, Dumbarton-
shire, do hereby declare the nature of this invention to be as follows:-
This invention relates to sewing machines and the improvements whilst in part
applicable to sewing machines generally are particularly adapted to the machine for
overseaming cutting and barring button holes described in the Specification of Letters
Patent Number 7964 of 1887.
The present invention embraces improvements in the fitting of the cutting blade or
knife and the means for operating it whereby the fabric is cut after the button hole is
stitched instead of during the stitching operation, in means for throwing the operating
parts of the machine out of action when the button hole is formed, in means for
raising and lowering the presser foot from a foot treadle instead of by hand and in a
tension device applied to the bobbin case of the shuttle carrying the under thread to
ensure a regular tension which will not vary as the thread is drawn off the cop or
hobbin.
The knife or cutter is made in the form of a vertical blade having a sharp V shaped
cutting edge and is adjustably attached to a carrying block fitted so as to be capable of
swivelling on a vertical bar carried in guides in the face plate of the machine so that
it may be swung out of the way when not in use but held normally in position for
effecting the cutting operation by means of a spring pressed pin fitted in the cutter
carrying block and whose end enters a recess on a projecting arm on the cutter bar.
The cutter bar is held up with the cutting blade above the fabric by means of a helical
or other spring surrounding it and attached to the back of the face plate and it is
depressed to cut the fabric by the reciprocating needle bar. For this purpose the
needle bar is fitted with a tappet which comes into contact with a lever arm centred
on the cutter bar and which is drawn forward into the path of movement of the said
tappet by means of a link jointed at one end to said arm and having at its opposite end
a stud or roller fitted in a cam groove in the barrel cam or feed wheel of the machine
the cam groove being formed to bring the lever arm into the actuating position at the
proper time for cutting the fabric.
For throwing the machine out of action when the button hole is made the feed
wheel is formed or fitted with an inclined projection which as the said wheel completes
each revolution comes in contact with a finger on a hand lever centred on the bracket
arm of the machine and having connected to it a link whose further end is connected
to one arm of a bell crank centred on the bed plate. The other arm of said bell crank
bears on a stud or roller on the lower arm of the usual three armed or Y-shaped
lever by the movement of which the friction driver is withdrawn from the balance
wheel on the main driving shaft and the friction brake applied to stop the machine
and by the action of the projection on the feed wheel the hand lever and bell crank
are thrown over to stop the machine. To restart the machine the hand lever is again
drawn forward towards the feed wheel the friction driver being thereby brought into
contact with the balance wheel and the friction brake relieved.
For raising the presser foot which is normally held down by a spring a wire cord
or chain connected by a link to the usual lifting bar or lever is carried up over guide
pulleys fitted on the bracket arm, thence down through the bed plate to a treadle below
which is acted on by the foot of the operator as required. This device is applicable
to sewing machines generally.
The improved tension device for the under thread and which is applied to the bobbin
case of the oscillating shuttle described in the Specification of Letters Patent

page_text: Number 17884 of 1887 consists of a cover hinged to the open end of the bobbin case
and having in it a thread slot or groove extending across the cover. To the outer face
of cover and lying over the thread slot is a light blade spring which is adjustably
secured to apply more or less tension by a screw pin. The said spring extends into
a recess formed in the cover and bears on a back plate extending across part of the slot
or groove and the thread from a cop placed within the bobbin case is led out through
the slot in the cover thence under the spring between it and the back plate along a
continuation of the groove or slot on the further side of the spring and thence into
the diagonal threading slot to the thread delivery hole in the bobbin case the tension
spring formerly provided at the latter point being dispensed with. A projecting piece
formed on the cover and entering a recess in the rim of the bobbin case at the diagonal
slot serves to hold the cover in position and prevent the thread leaving said slot,
the cover being held down by the heel or rear part of the shuttle which passes over
it when the bobbin case which is pivotted to the shuttle is in its working position.
Dated this Ninth day of May 1889.
CRUIKSHANK & FAIRWEATHER,
62, Saint Vincent Street, Glasgow, Agents.
COMPLETE SPECIFICATION.
Improvements in Sewing Machines.
We, ALEXANDER ANDERSON, Manager, and ROBERT ANDREW FERGUSON POLLOCK,
Mechanic, both of the Singer Manufacturing Company's Works, Kilbowie, Dumbarton-
shire, 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, and the improvements whilst in part
applicable to sewing machines generally are particularly adapted to the machine for
overseaming, cutting and barring button holes described in the Specification of Letters
Patent Number 7964 of 1887.
The present invention embraces improvements in the fitting of the cutting blade or
knife and the means for operating it whereby the fabric is cut after the button hole is
stitched instead of during the stitching operation, in means for throwing the operating
parts of the machine out of action when the button hole is formed, in means for
raising and lowering the presser foot from a foot treadle instead of by hand and in
a tension device applied to the bobbin case of the shuttle carrying the under
thread to ensure a regular tension which will not vary as the thread is drawn off
the cop or bobbin.
In the accompanying drawings which illustrate the invention figure 1 is a side
elevation and figure 2 a front view of a sewing machine embodying our improvements,
figure 3 is a vertical section of part of the machine and figures 4, 5, and 6, are
detailed views of the shuttle and bobbin case showing the improved tension device.
The machine represented in these drawings is in its general arrangement similar to
that described in the Specification of Letters Patent Number 7964 of 1887. The knife
or cutter is made in the form of a vertical blade A, having a sharp V shaped cutting
edge and is adjustably attached by a screw pin a, to a carrying block B, pivotted or
fitted so as to be capable of swivelling on a vertical bar C, carried in guides D, in the
face plate E, of the machine so that it may be swung out of the way, as indicated in
dotted lines, when not in use but held normally in position for effecting the cutting
operation by means of a spring pressed pin, fitted in the cutter carrying block B,
and whose end enters a recess on a projecting arm c, on the cutter bar C. The cutter
bar C, is held up with the cutting blade above the fabric by means of a helical or
other spring C, surrounding it and bearing on the top or attached to the back of
the face plate E, and it is depressed to cut the fabric by the reciprocating needle bar F.
For this purpose the needle bar is fitted with a tappet which comes into contact with
a lever arm G, centred at g, on the cutter bar C, and which arm G, is drawn forward

page_text: into the path of movement of the tappet f, by means of a link H, jointed at one
end to said arm G, and having at its opposite end a stud or roller which may be
fitted in a cam groove in the barrel I, or feed wheel J, of the machine or which
as shown may bear on the periphery of the cam I, on which a projection i, is formed
the cam groove or the projection i, being designed by acting on the link H, to bring
the lever arm G, into the actuating position at the proper time for cutting the fabric.
For throwing the machine out of action when the button hole is made the feed wheel J,
is formed or fitted with an inclined projection j, which as the said wheel completes each
revolution comes in contact with a finger k on a hand lever K, centred on the bracket
arm X, of the machine and having connected to it a link L, whose further end is
connected to one arm m, of a bell crank M, centred on the bed plate Y. The other
arm m', of said bell crank bears on a stud or roller n, on the lower arm of the usual
lever N, by the movement of which, the friction driver O, is withdrawn from the
balance wheel P, on the main driving shaft, and the friction brake Q, applied to stop
the machine; and by the action of the projection j, on the feed wheel J, the hand
lever K, and bell crank M, are thrown over to stop the machine. A slight degree of
eccentricity is given to the brake wheel Q¹, so that the pressure of the brake will be
applied to stop the machine when the needle is out of the fabric. To restart the
machine the hand lever K, is again drawn forward towards the feed wheel the friction
driver O, being thereby brought into contact with the balance wheel P, and the
friction brake relieved.
For raising the presser foot R, which is normally held down by the usual spring a
wire cord or chain S, connected by a links to the usual lifting bar or levers, is
carried up over a guide pulley s², fitted on the bracket arm and thence passes either
directly down through the bed plate to a treadle below or, as shown, is connected to
one end of a lever ST, to whose other end is attached a link or chain connected to the
said treadle which latter is acted on by the foot of the operator as required. This
device is applicable to sewing machines generally.
The improved tension device for the under thread and which is applied to the
bobbin case of the oscillating shuttle described in the Specification of Letters Patent
Number 17884 of 1887 and represented at figures 4, 5 and 6, consists of a cover T,
hinged to the open end of the bobbin case and having in it a thread slot or groove t,
extending across the cover. To the outer face of the cover T, and lying over the
thread slot t, is a light blade spring t, which is adjustably secured to apply! more or less
tension by a screw pin 2. The said spring extends into a recess t³, formed in the cover and
bears on a back plate extending across part of the slot or groove, or on the bottom of the
recess when the cover T, is made solid; and the thread from a cop placed within the
bobbin case is led out through the slot t, in the cover T, thence under the spring t,
between it and the back plate or bottom of the recess along a continuation of the groove
or slot t on the further side of the spring t¹, and thence into the diagonal threading
slot u, to the thread delivery hole u¹, in the bobbin case U, the tension spring
formerly provided at the latter point being dispensed with. A projecting piece v,
formed on the cover and entering a recess e', in the rim of the bobbin case U, at
the diagonal slot u serves to hold the cover in position and prevent the thread leaving
said slot, the cover being held down by the heel or rear part W₁, of the shuttle W,
which passes over it when the bobbin case which is pivotted at w, to the shuttle is in
ts working position.
Having now particularly described and ascertained the nature of our said inven-
ion and in what manner the same is to be performed we declare that what we
claim is:
-
1. The combination of parts constituting the improved sewing machine for over-
eaming barring and cutting button holes hereinbefore described with reference to
he accompanying drawings.
2. In a sewing machine a button hole cutting blade or knife pivotted on a
ertically moving bar operated from the needle bar substantially as described.

page_text: r
3. In a sewing machine the arrangement or combination of devices for operating
the blade or knife to cut the button liole on the completion of the stitching operation
substantially as described.
4. In a button hole sewing machine the combination with the cutter bar of the
lever arm G, operated from the barrel cam or feed wheel and a tappet on the
needle bar substantially as and for the purpose set forth.
5. In a button hole sewing machine the combination of devices for throwing
the operating parts out of action when the button hole is formed substantially as
described.
6. In a sewing machine the combination with the feed wheel or cam having
an inclined projection thereon of a finger on the land lever for throwing the
machine in and out of gear substantially as described.
7. In a sewing machine the combination with the hand lever K, and link L, of
the bell crank M arranged to operate the lever N by means of which the friction
driver and brake are thrown into and out of gear substantially as described.
8. In a sewing machine the arrangement of the cord or chain and foot treadle for
raising and lowering the presser foot substantially as described.
9. In a sewing machine shuttle of the class set forth a thread tension device formed
in the end cover of the bobbin case substantially as described.
Dated this Eighth day of February 1890.
CRUIKSHANK & FAIRWEATHER,
62, Saint Vincent Street, Glasgow, Agents.