Improvements in Two Needle Sewing Machines.
Year: 1898

page_text: Date of Application, 1st Feb., 1898-Accepted, 30th Apr., 1898
[Communicated from. abroad by THE SINGER MANUFACTURING COMPANY, of New
York, United States of America, Sewing Machine Manufacturers.]
Improvements in Two Needle Sewing Machines.
I, 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 has for its object to provide means, of simple construction, whereby
one of the needles of a two-needle sewing machine may be thrown into or out of
operation without stopping the machine, it being frequently desirable, with this
class of machines, to suspend the operation of one of the needles for a few stitches,
as in turning square corners.
In the drawings Fig. 1 is a rear side elevation of a "Singer" sewing machine
embodying my invention, and Fig. 2 is a partial plan view of the head of the same.
Figs. 3, 4, 5 and 6 are detail views of upper parts of the two needle-bars and their
connections, and Fig. 7 is a partial front view of the head with the face-plate
removed.
In the form of my invention herein shown the contiguously placed needle-
bars a, a', each carrying a needle b, are made as half round bars so as to reciprocate
in the usual round bearings in the head at the forward end of the arm A, the
needle-bar a being connected in the usual manner to the crank at the forward end
of the driving shaft journalled in the upper part of said arm. The needle-bar a¹ is
coupled to the bar a by a pin c free to slide horizontally in a collar d brazed or
otherwise rigidly secured to the bar a¹ at or near the top thereof. The head of
the pin c has an aperture through which freely passes a rod or arm e of a small rock-
shaft journalled in a block g and having a second arm h joined by a connecting
rod i to a lever k pivoted at m and extending down through the work-plate B, so
as to be operated from beneath said work-plate by any suitable treadle or knee-lever
connections.
A spring n attached to the standard of the arm A and to the lever k below the
fulcrum of the latter presses the upper end of said lever forward and thus normally,
through the rod i, arm h, rock-shaft f and arm e, holds the coupling pin c in
connection with the main needle-bar a, so that the auxiliary needle-bar a¹ will be
caused to reciprocate vertically with the main needle-bar, owing to this coupled
connection of the two bars; the head of the pin c at such times reciprocating freely
on the rod or arm e passing loosely through the hole in said head.
When it is desired to throw the auxiliary needle-bar a¹ out of operation the
attendant moves the lower end of the lever k forward, or in opposition to the stress
of the spring n, thus throwing the upper end of the rod or arm e outward far
enough so that when the needle-bars are at the top of their stroke the coupling pin
will be withdrawn from the main needle bar, which latter will continue to
reciprocate while the auxiliary needle-bar, being now disconnected from its means

page_text: of operation, will remain at rest, being retained in its raised position by a spring o
interposed between a collar attached to the main needle-bar a and a collar r
fast on the auxiliary needle-bar a', the operating pitman for the said main needle-
bar a being connected with said collar 2. The dotted lines in Fig. 1 denote the
position of the parts when the needle-bars are disconnected from each other.
When the auxiliary needle-bar a¹ is again to be set into operation the lever k
is released and is restored to its normal position by the spring n, and the coupling
pin c is thus pressed inward so that as the main needle-bar a rises said pin rides
over an interior incline a² of the said bar a and then snaps into its coupling hole in
said bar when the latter reaches the top of its upstroke.
It will thus be understood that by means of the devices herein described the
auxiliary needle-bar may be thrown into or out of operation without stopping
the machine, so that in turning corners, where it is desirable to shorten one row of
stitches, this may be done without delay or trouble, the attendant controlling the
action of the auxiliary needle-bar by a knee-lever or treadle, leaving the hands free
to manipulate the work.
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. In a sewing machine, the combination with the needle-bars a and a³, of the
coupling pin c, the rock-shaft f having the arm e engaging said coupling pin and
the arm h, the lever k, its controlling spring n and the rod i connecting said lever
with said arm h.
2. In a sewing machine, the combination with the two contiguously placed
needle-bars a and a', the former having the incline a², of the coupling pin c, means
for yieldingly pressing said pin towards said incline and means for withdrawing
said pin when the auxiliary needle-bar al is to be uncoupled from the main needle-
bar a.
3. In a sewing machine, the combination with the two contiguously placed
needle-bars a and a', the former having the inclines, of the coupling pin c, the rock-
shaft f having the arm e, engaging said coupling pin, and the arm h, the spring-
actuated lever k, the rod i connecting said lever with said arm h, and a spring for
holding said needle-bar a¹ in an elevated position when said coupling pin is
withdrawn from said bar a.
4. In a sewing machine, the combination with a main needle-bar, of an auxiliary
needle-bar, a coupling device, carried by said auxiliary needle-bar, for connecting
one of said needle-bars to the other, an actuating lever, and connections between
said lever and said coupling device whereby the latter may be actuated to connect or
disconnect said needle-bars without stopping the machine.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62, Saint Vincent Street, Glasgow,
Agent for the Applicant.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62, Saint Vincent Street, Glasgow,
Agent for the Applicant.