Improvements applicable to Overedge Sewing Machines to Adapt them for Hand-stitch Hemming.
Year: 1898

page_text: Date of Application, 24th Nov., 1898
Complete Specification Left, 19th Aug., 1899-Accepted, 4th Nov., 1899
PROVISIONAL SPECIFICATION.
Improvements applicable to Overedge Sewing Machines to Adapt
them for Hand-stitch Hemming.
I, DAVID JOHNSTON MACDONALD, of South Saint Roque's Works, Dundee, in
the County of Forfar, North Britain, Engineer and Machine Maker, do hereby
declare the nature of this invention to be as follows, that is to say:-
My said invention relates to sewing machines of the kind in which a helical
or similar needle forms an overedge stitch, and which is ordinarily used for
sewing sacks or similar work, and my object is, by improved appliances, to adapt
such machines for hand-stitch hemming.
In carrying out my invention the fabric to be hemmed is moved through the
machine by means ordinarily employed in such machines; but on approaching
the needle, passes through a scroll guide consisting of a pair of twisted blades
fixed at their entering end to the machine framing. The action of the scroll
guide causes the edge of the fabric to be folded; and the fabric on leaving the
scroll guide passes under a spring finger which doubles the fold. The thus
folded part is at the same time laid or folded on the part of the fabric within
the hem, and the stitching takes place through the last-named part and the folded
part. On the fabric being removed and on the hem being flattened out it resem-
bles an ordinary hand-stitched hem.
The scroll guide may be varied in shape so as to produce one, two, or more
foldings of the edge of the fabric, the spring finger being used or not as may be
found advantageous in each case.
.”
Π
1 1
1000
EDMUND HUNT,
Applicant's Agent,
Improvements applicable to Overedge Sewing Machines to Adapt
them for Hand-stitch Hemming.
I, DAVID JOHNSTON MACDONALD, of South Saint Roque's Works, Dundee, in
the County of Forfar, North Britain, Engineer and Machine Maker, 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:-
My said invention relates to sewing machines of the kind in which a helical
or similar needle forms an overedge stitch, and which is ordinarily used for

page_text: sewing sacks or similar work, and my object is, by improved appliances, to adapt
such machines for hand-stitch hemming.
And in order that my said invention and the manner of performing the same
may be properly understood, I hereunto append a sheet of explanatory drawings
to be hereinafter referred to in describing my improvements.
In the accompanying drawings Figures, 1, 2, and 3, are respectively a plan,
a side elevation, and a transverse vertical section of part of a machine provided
with my improvements. Figures, 4, 5, and 6, are respectively a plan, a side
elevation, and an end elevation on an enlarged scale of part of the improved
appliances. Figures, 7, and 8, are a plan and a side elevation, also on an
enlarged scale, of another part of the improved appliances. In these drawings
the same reference letters and numerals are used to mark the same or like parts
wherever they are repeated.
My improvements are shown in the drawings as applied, by way of example,
to an overedge sewing machine of the kind described in Hunt's Patent Specifica-
tion No. 2856 of 1878, in which a helical needle (not shown) is held and driven
by grooved conical wheels, A, driven by bevil gear, A 1, from the main shaft, B,
of the machine. In order to show the improvements clearly, the machine is shown
with some parts removed. In carrying out my invention the fabric to be hemmed
is placed on the guide plate, C, extending along in front of the machine, and
before being brought forward in front of the needle, it is passed through a scroll
guide, D, shown on an enlarged scale in Figures, 4, 5, and 6, consisting of a pair
of twisted blades, D1, D2, formed with a flanged part, D3, at their entering
end by which they are fixed by screws, D4, to the machine table or framing.
A curved spring finger, E, shown on an enlarged scale in Figures, 7, and 8, is
fixed by screws, E1, to the machine table in close proximity to the
scroll guide, D, and acts in conjunction with it. The action of
the scroll guide, D, causes the edge of the fabric, as it passes
through, to be folded; and the fabric on leaving the scroll guide passes under
the spring finger, E, which doubles the fold. The thus folded part is at the
same time laid or folded on the part of the fabric within the hem, and the
stitching takes place through the last-named part and the folded part. The
folded parts as they leave the scroll guide and spring finger, are caught by the
projecting spikes of the feed chain, G, entering under a specially formed pressing
or holding down bar, H, to be hereinafter described, which holds the fabric firmly
down onto the chain and feed table. The movement of the feed chain, G, carries
the fabric forward in front of the needle, and the folded parts are then stitched
in the usual way. On the fabric being removed, and on the hem being flattened
out it resembles an ordinary hand-stitched hem. The scroll guide, D, may
be varied in shape so as to produce one, two or more foldings of the edge of the
fabric, the spring finger, E, being used or not as may be found advantageous in
each case.
The arrangement of pressing bar previously in use has been found
defective and inconvenient with the considerable thickness of material occurring
in carrying out the present invention; and the pressing bar, H, hereinbefore
referred to, is designed so that the whole length of the bar rises when the folded
parts of the fabric are entered under it, instead of only part of the bar rising as is
ordinarily arranged. The pressing bar, H, is fixed to vertical rods, H 1, adjust-
ably fixed to curved two armed levers, H2, fixed by pinching screws, H3, or
otherwise to a shaft, H4, mounted in brackets, H5, fixed to the framing, the
ends of the lower arms of the levers passing through guide slots, HG, formed
in the framing. A spring, H7, is provided on the lower arm of each lever, H2,
to give the necessary pressure to the bar, H, the pressure being conveniently
adjusted by nuts, H8, working on a screwed part of the arm, and acting on the
spring. The height of the pressing bar, H, may be adjusted to any required
position by means of the nuts, H 9, on the vertical rods, H 1. A ratchet wheel,
J, fixed to the main shaft, B, and driven by a pawl. J 1, worked by
a foot

page_text: lever, J 2, is provided for the purpose of enabling the needle to be worked by
foot motion when desired for any special purpose.
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. Improvements applicable to overedge sewing machines, comprising a scroll
guide, consisting of a pair of twisted blades, fixed at their entering end to the
machine framing, and acting with or without a spring finger, also fixed to the
framing, substantially as and for the purposes hereinbefore described with
reference to the accompanying drawings.
2. In overedge sewing machines, a pressing or holding down bar, arranged
to move as a whole, in combination with the scroll guide and spring finger, the
bar being adjustably fixed to levers centered on the framing, and acted on by
springs substantially as and for the purposes hereinbefore described with reference
to the accompanying drawings.
Dated this Eighteenth day of August 1899.
EDMUND HUNT,
Applicant's Agent.