Improvements in Overedge Sewing Machines.
Year: 1889

page_text: Date of Application, 21st Aug., 1889
Complete Specification Left. 20th May. 1890-Accepted, 21st June, 1890
PROVISIONAL SPECIFICATION.
Improvements in Overedge Sewing Machines.
We, WILLIAM ROBERTSON, and JAMES GUTHRIE ORCHAR, of Wallace Foundry,
Dundee, in the County of Forfar, North Britain, Engineers, WILLIAM ADIE, of the
same place, Draughtsman, and THOMAS ROBERTSON, of the same place, Foreman, do
hereby declare the nature of this Invention to be as follows, that is to say :-
-
Our said Invention relates to overedge sewing machines of the kind described in
James Laing's Patent Specification No. 3493 of 1874, and working with a helical
needle, and our Invention comprises improvements in various parts of such machines.
In carrying out our Invention according to one modification we use a parallel or
cylindrical helical needle, which is by preference rectangular in section; and we
drive it by the direct contact action on its outer surface of three cylindrical pulleys or
drivers which have pinions formed in the same pieces with them or fixed to them.
One of the drivers which is at the back of the needle is on a horizontal shaft driven
in any convenient way, and the other two drivers are driven by intermediate pinions
gearing with their pinions and that of the back driver. The drivers have bearings or
housings at both ends; and the top one is held in a bracket centered concentrically
with the intermediate pinion driving the top driver, a bar and screw being provided
for fixing the top driver in the driving position with the necessary pressure. The
drivers may be made with flanges, if required, to retain the needle endways, and each
has on it a shell in the form of a helix the convolutions of which enter between the
convolutions of the needle, the shell being designed to keep the needle correctly in
position with its convolutions at proper distances apart. The helical shell is made
with a pitch suitable for the purpose; or it may be made adjustable in pitch by being
compressed more or less endways by one of the driver flanges made adjustable by
screwing or otherwise.
Instead of the drivers being provided with loose helical shells they may be made
with helical grooves, but in that case the grooves are made so that their bottoms only
drive the needle. The needle may be made with shallow indentations or projections,
or of an undulated form, the drivers being made with counterpart indentations,
projections, or undulations. The driving surfaces of the drivers may be of metal,
leather, paper, or other suitable material. The needle may be in the form of a conical
helix the drivers being made conical also. In some cases the needle may be of an
elliptical form in section.
The movement of the thread barrel and the regulation of the tension of the thread
are derived from the rotation of the barrel and the action of each successive loop, as
it reaches the end of the barrel, on an end piece fitted into the end of the barrel so as
to be drawn a little to the side by the tensional strain of the thread. A spindle passes
through the thread barrel and is made to turn by the barrel through the action of the
end piece. At its other end the spindle is held between collars in part of a slide fitted
to move on guides and which is drawn backwards by a cord passing over a pulley to
a weight. A pinion on the end of the spindle gears with a spurwheel which is carried
by the slide and which has formed with or fixed to it a grooved pulley; or this pulley
may be fixed directly on the spindle. A cord passing over this pulley passes at each
side under guide pulleys and thence horizontally forwards to a differential pulley
centered on a stud on the fixed frame of the machine. The differential pulley is made
with separate grooves or barrels for the two sides of the cord, these grooves or barrels
being of different diameters; and each side of the cord makes one or two turns round
the pulley, and a loop of the cord, which is endless, hangs down and has a suitable
strain put on it by a weighted pulley. When the spindle of the thread barrel turns,
the parts described cause the differential pulley to turn in a manner to slightly slacken

page_text: the parts of the cords between it and the slide, and the slide is moved by the weight
acting on it and moves back the spindle and the thread barrel. The grooves or
barrels of the differential pulley are proportioned to give a suitable movement to the
slide. An important advantage of this improved arrangement is that no parts require
to be put out of gear when the barrel has to be moved forward again for a fresh seam,
all that is needed being to move forward the slide by means of a handle with which it
is provided for the purpose.
Dated this Twentieth day of August 1889.
EDMUND HUNT,
Applicants' Agent.
COMPLETE SPECIFICATION.
Improvements in Overedge Sewing Machines.
We, WILLIAM ROBERTSON, and JAMES GUTHRIE ORCHAR, of Wallace Foundry,
Dundee, in the County of Forfar, North Britain, Engineers, WILLIAM ADIE, of the
same place, Draughtsman, and THOMAS ROBERTSON, of the same place, Foreman, 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, that is to say :-
Our said Invention relates to overedge sewing machines of the kind described in
James Laing's Patent Specification, No. 3493 of 1874, and working with a helical
needle and our Invention comprises improvements in various parts of such
machines.
In carrying out our Invention according to one modification, we use a parallel or
cylindrical helical needle which is by preference rectangular in section; and we drive
it by the direct contact action on its outer surface of three cylindrical pulleys or
drivers, which have pinions formed in the same pieces with them or fixed to them.
The drivers are held in an improved manner, and each has on it a shell in the form of
a helix the convolutions of which enter between the convolutions of the needle, the
shell being designed to keep the needle correctly in position with its convolutions at
proper distances apart. The helical shell is made with a pitch suitable for the purpose;
or it may be made adjustable in pitch by being compressed more or less endways by
flanges on the drivers made adjustable by screwing or otherwise.
Instead of the drivers being provided with loose helical shells, they may be made
with helical grooves, but in that case the grooves are made so that their bottoms only
drive the needle. The needle may be made with shallow indentations or projections,
or of an undulated form, the drivers being made with counterpart indentations,
projections, or undulations. The driving surfaces of the drivers may be of metal,
leather, paper, or other suitable material." Some of our improvements are applicable
with the needle in the form of a conical helix ; and in some cases the needle may be
of an elliptical form in section.
The movement of the thread barrel, and the regulation of the tension of the thread
are derived from the rotation of the barrel, and the action of each successive loop, as
it reaches the end of the barrel, on an end piece fitted into the end of the barrel so as
to be drawn a little to the side by the tensional strain of the thread. A spindle
passes through the thread barrel and is made to turn by the barrel through the action
of the end piece. According to the present. Invention this spindle is at its other end
held between collars in part of a slide drawn backwards by a weight, the backward
movement being controlled by a differential arrangement hereinafter more particularly
described, and which is acted on by the turning of the spindle. An important
advantage of the improved arrangement is that no parts require to be put out of gear
when the barrel has to be moved forward again for a fresh seam, all that is needed
being to move forward the slide by means of a handle with which it is provided for
the purpose.
And in order that our said Invention and the manner of performing the same mav

page_text: be properly understood we hereunto append two sheets of explanatory drawings to
be hereinafter referred to and representing our improvements.
Figure, 1, on sheet, 1, of the drawings is a plan of an overedge sewing machine
as made according to our Invention, and figure, 2. is a corresponding front eleva-
tion with a part in section. Figure, 3, is a traverse section of parts near the left-
hand end of the machine, and figure, 4, is an elevation of the helical needle which
cannot be well shown in figures, 1, and 2. Figure, 5, on sheet, 2, is a transverse
vertical section of the machine at the part where the needle is; and figures, 6,
to 10, are enlarged views hereinafter specially referred to. In these drawings the
same reference letters and numerals are used to mark the same, or like parts where-
ever they are repeated.
One, D1, of the three driving pulleys or drivers, which is at the back of the
needle, N, is on a horizontal shaft, A, driven in any convenient way, as for example, by
a pinion and spurwheel, A 1, A 2, from a first-motion shaft, A 3, having on it fast and
loose pulleys, A 4, for a driving belt. The other two drivers, D2, D3, are driven by
intermediate pinions, D4, D5, running on studs and gearing with pinions formed on or
fixed to the drivers. The drivers have bearings or housings, H, at both ends; and the
top driver, D3, is held in a bracket, H 1, centered concentrically with the intermediate
pinion, D4, driving it, a removable bar, H 2, and screw, H3, being provided for fixing
the bracket, H 1, with the top driver, D3, in the driving position with the necessary
pressure. The drivers, D 1, D2, D3, may be made as shown in figures, 1, and 2, with
flanges to retain the needle end ways; and each driver has on it a shell, C, in the
form of a helix, the convolutions of which enter between the convolutions of the
needle.
The arrangement, manner of driving, and operation of the thread barrel, B, is
much the same as in existing machines of the same class, a spindle, S, extending
through it being made to turn with the barrel whenever the tenison of the loop of
thread on a piece, B 1, at the right-hand end reaches the degree for which the parts
are adjusted. At its left-hand end the spindle, S, is held between collars, S1, S2, in
part of a slide, S 3, fitted to move on guides, E, extending from the main part of the
framing. The slide, S 3. is drawn backwards (towards the left) by a cord, E 1, passing
over a pulley to a weight, E 2. A pinion, S 4. fast on the end of the spindle, S, gears
with a spurwheel, T, which is carried by the slide, S 3, and which has formed with or
fixed to it a grooved pulley, T 1, (or this pulley might be fixed directly to the spindle, S).
A cord, T2, passing over the pulley, T 1, passes at each side under guide pulleys, T 3,
and thence horizontally forwards to a differential pulley, T 4, centered on a stud on the
fixed frame of the machine. The differential pulley, T4, is made with separate
grooves or barrels (as indicated by dotted lines in figure, 1,) for the two sides of the
cord, T 2, these grooves or barrels being of different diameters; and each side of the
cord makes one or two turns round the pulley, and a loop of the cord which is endless,
hangs down and has a suitable strain put on it by a weighted pulley, T 5. When the
spindle, S, of the thread barrel, B, turns, the parts described cause the differential
pulley, T 4, to turn in a manner tos lightly slacken the parts of the cord, T 2, between
it and the slide, S3, and the slide is moved by the weight, E 2, acting on it and moves
back the spindle, S, and the thread barrel, B. The grooves or barrels of the
differential pulley, T4, are proportioned to give a suitable movement to the slide, S 3,
and a handle, S 5, is fixed to this slide for the purpose of moving it, and with it
the thread barrel, B, towards the right when a fresh seam is to be commenced.
In figures, 6, 7, and 8, sheet, 2, there are shown a modified form of driver, D, and
a form of needle, N, suitable for such a driver. Figure, 6, is an elevation, figure, 7,
a transverse-sectional diagram, and figure, 8, a longitudinal section. The driver, D,
is not fitted with a loose shell or helix (C) but is made with grooves which in the
example shown in these figures are made of a form suitable for a needle, N, of square
section, with a diagonal of the square at right angles to the axis of the thread
barrel, B. On the outer angular ridge of the needle, N, wave-shaped or undulatory
indentations are formed, and the groove of the driver, D, is made with partly

page_text: filled up parts which are counterparts of and gear with the undulatory indentations
of the needle.
Figure, 9, is a longitudinal section similar to figure, 8, but showing the needle, N,
as of a round section; and as made with undulatory indentations on its outer part,
the driver, D, being made with grooves of undulatory form, with partly filled up
parts to gear with the indentations of the needle. Figure, 10, is a longitudinal
section showing the needle, N. as of square section but with the outer and inner sides
of the squares parallel to the axis of the thread barrel, B; and the driver is shown as
made with grooves of a similar form but wider than the needle. The needle is made
with undulatory indentations in its outer surface, the grooves in the driver
having the bottom shaped with counterpart undulatory protuberances to gear
therewith.
Having now particularly described and ascertained the nature of our said Inven-
tion and in what manner the same is to be performed, we declare that what wo
claim is
1. The arrangement of a helical needle with drivers adapted to act only on its outer
surface, in combination with loose shells or helices on the drivers or with grooves
wider than the needle, substantially as hereinbefore described.
2. The improved forms of the needle and drivers-the needles having on their
outer surfaces shallow indentations, projections, or undulations, and the drivers having
counterpart parts to engage therewith, substantially as hereinbefore described.
3. The arrangement of the drivers in bearings or housings at both ends,
combined with the arrangement of the movable bracket of the top driver with the
bar and screw for holding and adjusting it in position, substantially as herein before
described.
4. The combination of the differential pulley and other parts by which the move-
ments of the thread barrel are controlled and regulated, substantially as herein before
described.
1
JSM 1900
EDMUND HUNT,
Applicants' Agent.