Improvements in Double Chain Stitch Sewing Machines.
Year: 1896

page_text: Date of Application, 29th Dec., 1896-Accepted; 1st May, 1897
Manufacturers.].
Improvements in Double Chain Stitch Sewing Machines.
WILLIAM HARVEY INSLEE, Manager of The Singer Manufacturing
Company, Kilbowie, Dumbartonshire, do hereby declare the nature of this
invention and in what manner the same is to be performed, as communicated
to me, to be particularly described and ascertained in and by the following
statement:-
My invention relates to double chain stitch sewing machines, and has for its
object to provide an improved looping mechanism for this class of machines, and
which, while well suited for single needle machines, is also adapted for double chain
stitch machines employing two or more needles and loopers for producing two or
more parallel rows of stitches at one operation.
In carrying my invention into effect the thread-carrying looper or loopers
are arranged to vibrate back and forth lengthwise in one plane transversely of
the machine, or in the direction of the feed of the work, and in co-operation with
said looper or loopers I employ a spreader or spreaders for the loops of the needle
thread or threads and a spreader or spreaders for the loops of the looper thread or
threads, said spreaders reciprocating longitudinally of the machine, or transversely
to the plane of movement of the looper or loopers.
.
In the accompanying drawings
Fig. 1 ie a sectional view of a sewing macbine embodying my invention.
Fig. 2 is a front end view thoreof with the face-plate of the head and the cap of
the work-supporting arm or cylinder removed.
Fig. 3 is a front end view of the lower part of the machine.
Fig. 4 is a side view and Fig. 5 a plan view of the same.
Fig. 6 is a plan view similiar to Fig. 5, but with some parts omitted for
clearness.
Fig. 7 is a detail top view of the loopers and looper carrier, and
Fig. 8 a detail plan view illustrating a modified form of my invention.
In the drawings I have shown my invention applied to a two-needle "left-hand
cylinder" machine the frame-work of which comprises the standard A, the over-
banging arm A' and the work-supporting arm or cylinder A. The driving shaft B,
journalled in the lower part of the framework, is provided near its rear end with a
crank b connected by a pitman c to an arin at the rear end of the needle-operating
rock-shaft C having at its forward end an arm connected in a well-known manner
by a pitman to the needle-bar c; herein shown as provided with two diagonally
arranged needles for making two closely arranged rows of stitches. The
shaft B has at its forward end a crank 61 connected by a link d to a vibrating
looper-carrier D pivoted at its lower end, at d', and provided with the thread-
carrying loopers d, the latter being thus reciprocated back and forth longitudinally
(or in the direction of their length) in the same plane, or without lateral
movements.
To open the loops of the needle thread or threads, or to spread them laterally
so that they will be entered by the points of the loopers, I provide spreaders or

page_text: loop pushers e carried at the forward end of the reciprocating rod E, the rear
end of which is jointed to a connection el having a strap-portion surrounding and
entered into a diagonal groove of a screw cam & on the shaft B, and which moves
the upper end of the said connection back and forth to reciprocate the rod E, the
joint between said connection and rod being an universal one, to avoid binding.
Any other suitable operating device for the reciprocating rod E may, howover,
be employed. The loop-spreaders or pushers e move forward or outward in close
proximity to the needles as the latter are rising, and thus push or. spread the
needle loops laterally to ensure the entrance of the points of the advancing loopers d'
into the same.
To ensure the entrance of the needles into the loops of looper-threads I provide
spreaders or spreading hooks e which are also carried by the reciprocating rod E,
said spreaders or hooks, on the inward or return movements of said rod, catching
the looper threads running from the loopers up to the work and drawing the
eame out sidewise to form loops for the entrance of the needles as the latter
descend.
I thus provide, in connection with a thread-carrying looper, reciprocating
transversely of the machine, or in the direction of the feed of the work, and
performing both its forward and backward movements in the same path, two
reversely or alternately acting loop spreaders, one spreader spreading a needle-
loop on its outward movement, when the looper is advancing, and the other
spreader spreading a looper loop on its inward movement when the looper is
retreating. The movements of the looper or loopers are thus simplified and a
part of the work usually performed by the thread carrying, loopers is transferred
to the reversely operating spreaders; and as only very short movements are
required for the latter, and as they may be made small and light, very little
friction results.
In the form of my invention shown in Fig. 8, and in which the needles c³ (which
are arranged for wider gauged seams than are the diagonally placed needles of the
machine shown in the other figures) are placed abreast of each other, a single
needle-loop spreader e³, formed as a straight bar to rub against the needle loops as
it moves forward or outward will serve, simply by frictional contact with the needle
threads, to spread the loops of two or more needles arranged abreast of each
other or in the same plane as that in which said spreader moves. Also in this
form of my invention the looper-loop spreaders or spreading hooks et are formed
on one and the same bar or plate, one behind the other, instead of being made as
separate books as shown more clearly in Figs. 3 and 5, for co-operation with the
diagonally arranged needles employed for making two closely arranged seams.or
rows of stitches.
The loopers co-operating with the diagonally arranged needles are preferably of
different lengths, as shown, so that they will both take the loops of the two needle
threads at the same instant.
In the use of my improved machine, with the loopers reciprocating in the
plane of the feed of the work and with the loop-spreaders reciprocating transverse
to the plane of the feed of the work, the needles are arranged so that their eyes
extend or open through the needles in, the direction of. the feed of the work,
as is usual with double chain-stitch machines, the needle-loop spreaders or
pushers e of my improved machine acting on the needle loops, to open them
for the entrance of the points of the loopers, on the short groove sides of the
needles.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
1. In a double chain stitch sewing machine, the combination with a needle and
its operating mechanism, of a thread-carrying looper arranged to reciprocate
longitudinally in the plane of the feed of the work, the forward and backward

page_text: movements of said looper being both in the same path, two alternately acting loop-
spreaders, one for the needle-loops and the other for the looper-loops, and both
arranged to reciprocate in a plane transverse to the plane of movement of' said
looper, a looper-carrier, and operating mechanism for said looper carrier and.
loop-spreaders.
2. In a double chain stitch sewing machine, the combination with a needle-
and its operating mechanism, of a thread-carrying looper arranged to reciprocate.
longitudinally in the plane of the feed of the work, the forward and backward
movements of said looper being both in the same path, a needle-loop spreader and a..
looper-loop spreader reciprocating together transversely to the plane of movement
of said looper, and acting alternately on the needle and looper threads, a looper-.
carrier, and operating mechanism for said carrier and spreaders.
3. In a double chain stitch sewing machiue, the combination with a plurality of
needles and their operating mechanism, of a work-supporting arm or cylinder, a.
driving shaft extending through the latter and provided at its forward end with
a crank or looper-operating device, a looper carrier pivoted at the forward end of
Baid arm or cylinder and provided with a plurality of thread-carrying loopers
arranged to reciprocate longitudinally in the plane of the feed of the work,
Baid looper-carrier being operatively connected with said crank or operating..
device, alternately acting needle-loop and looper-loop spreaders reciprocating in a
plane transverse to the plane of movement of said loopers, and a sliding rod,
operatively connected with said driving shaft, for operating said loop-spreaders.
Dated this 28th day of December 1896.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62 St. Vincent Street, Glasgow, Agent for the Applicant..