Improvements in Sewing Machines.
Year: 1886

page_text: Date of Application, 29th June, 1886.
Complete Left, 29th Mar., 1887.
Complete Accepted, 29th Apr., 1887.
Improvements in Sewing Machines.
I, ALEXANDER ANDERSON, Manager of the Singer Manufacturing Company's
Works, Kilbowie Dumbartonshire, do hereby declare the nature of this invention
to be as follows:-
This invention relates to sewing machines wherein are employed a reciprocating
needle bar and needle for the upper thread and a shuttle carried in a vibrating carrier
for the under thread the devices for actuating a feed bar as well as those employed for
operating the shuttle carrier being driven directly from the main shaft which
actuates the needle bar, and it comprises improvements due to the combination of the
several operating parts and to minor combinations embracing the feed regulating
devices and the mechanism for operating the feed bar.
Under the invention the main shaft which is carried in the overhanging arm of the
machine and actuates the needle bar through suitable connections is provided with an
elbow or inclined portion straddled by arms at the upper end of a vertical rock shaft
fitted in the bracket arm and having at its lower end an arm or crank which below the
bed-plate is connected by a link to an arm or lug of a shuttle carrying lever, said lever
being carried on a vertical rock shaft also below the bed plate and having formed on it
a carrier for the reception of the shuttle which is vibrated in a shuttle race in the arc
of a circle.
.The feed bar is jointed to a horizontal rock shaft which imparts to it a horizontal
reciprocating movement while it is raised and lowered at the forward and return
reciprocation by a cam on the vertical rock shaft which forms the pivot of the vibrating
shuttle carrying lever. An arm at the opposite end of the horizontal rock shaft is
connected to a link or lever extending upwardly into the bracket arm (to which it is
pivotally connected) and forked at its upper end to embrace a cam on the main shaft
the cam imparting through said link or lever the rocking motion to the horizontal
+91

page_text: rock shaft which reciprocates the feed bar. The link or lever referred to is fitted with
a stud entering a groove or slot in a guide piece which is adjustable by a screw or
similar device to bring the slot or groove from a horizontal to an inclined position or
vice versa; and while the forked end of the link or lever is vibrated horizontally by
the cam on the main shaft the slotted guide acting upon the stud on said link imparts
to.it a short vertical reciprocation which varies according to the degree of inclination
of the slot in which the stud works and thereby varies the extent of movement of the
rocking shaft of the feeding mechanism and the reciprocation of the feeding bar and
consequently the length of the stitch. In lieu of directly fitting the pivotted link
from the arm of the horizontal rocking shaft to be acted on by the cam on the main
shaft its upper end may be fitted in a slotted lever pivotted on the bracket arm and
operated by the cam referred to, the point of attachment of said link being by a pin
adjustably fitted in the slot of the lever to vary the extent of movement of the
rocking shaft of the feeding Mechanism.
11° Π
1
11 1
T
1000
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow,
Agents.
COMPLETE SPECIFICATION.
Improvements in Sewing Machines.
I, ALEXANDER ANDERSON, Manager of the Singer Manufacturing Company's Works,
Kilbowie, Dumbartonshire, 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 wherein are employed a reciprocating
needle bar and needle for the upper thread and a shuttle carried in a vibrating carrier
for the under thread, the devices for actuating the feed bar as well as those employed
for operating the shuttle carrier being driven directly from the main shaft which
actuates the needle bar, and it comprises improvements due to the combination of the
several operating parts and minor combinations embracing the mechanism for operating
the feed bar and regulating the feed.
In the accompanying drawings figure 1 is a skeleton view of a sewing machine
embodying this invention, the frame of the machine being shown by dotted lines.
Figure 2 is a detail of the right hand end view of figure 1, with the belt wheel
removed, the frame-work being shown by dotted lines except at the point where the
feed regulating screw is extended through it, the figure being made chiefly to show
the devices employed to effect the feeding of the material to be sewed. Figure 2ª is
a detail of the limk. Figure 3 a sectional detail to be referred to. Figure 4 an
enlarged detail of the slotted guide, change of position of which effects alterations in
the length of the stitch. Figure 5, a modification of the feed regulating device.

page_text: Figure 6 is a detail showing separately the shuttle carrier not fully shown in
figure 1.
Under this invention the main shaft A, which is carried in the overhanging arm B,
of the machine and actuates the needle-bar C through suitable connections as shown
is provided with an elbow or inclined portion A', straddled by arms eat the upper end
of a vertical rock shaft E, fitted in the bracket arm B and having at its lower end an
arm or crank e¹ which below the bed plate A, is connected by a link e² to an arm or
lugf of a shuttle carrying lever F, said lever being carried on a vertical rock shaft
or as shown on a rocking hub f', pivotted on a stud f³, secured to the underside of the
bed plate and having formed on it a carrier F¹, for the reception of the shuttle which
is vibrated in a shuttle race in the arc of a circle. The feed bar g forms part of a
frame G, which is jointed to ears g' on a horizontal rock shaft H, which imparts to it
a horizontal reciprocating movement, whilst it is raised and lowered at the forward and
return reciprocation by a cam f on the rocking hub for vertical rock shaft, which
forms the pivot of the vibrating shuttle carrying lever. An arm h at the opposite end
of the horizontal rock shaft H is connected to a link or lever I, extending upwardly
into the bracket arm B, to which it is pivotally connected, said link or lever being
forked at its upper end I¹, to embrace a cam J, on the main shaft A, the cam imparting
through said link or lever I, the rocking motion to the horizontal rock shaft H, which
reciprocates the frame G and feed bar g. The link or lever I is fitted with a stud k
entering a groove or slot in a guide piece or block L, which has on it a stud mounted
loosely on the arm B of the machine and serving as a fulcrum for the guide block L,
which is adjustable on the stud as a centre by a screw m and stitch regulating nut n
or similar device to place the slot or groove in a position at a greater or less
inclination to the horizontal or vice versa. In the present instance the screw m is
connected at one end to an ear on the guide piece L, and at the opposite end enters
the screw nut n which is screwed both externally and internally the external screw
threads which engage a threaded portion of the arm B being of greater pitch than
those of the screw m which is moved longitudinally on turning the nut n. Whilst the
forked end I¹ of the link or lever I is vibrated horizontally by the cam J, on the main
shaft A, the slotted guide L, acting upon the stud k, on said link or lever imparts to it
a short vertical reciprocation which varies according to the degree of inclination of
the slot in which the stud k works, and thereby varies the extent of movement of the
rocking shaft H, and the reciprocation of the feeding bar and consequently alters the
length of the stitch. The greater the inclination of the slot 7 the greater will be the
extent of movement lengthwise of the link I, and the longer the stitch. In lieu of
directly fitting the link I, to be acted on by the cam on the main shaft, its
upper
may be connected as shown at figure 5 to a slotted lever L' pivotted_at
bracket arm B and operated by the cam J, the attachment of said link I, being by a
pin or stud i fitted in the slot 1 of the lever L'. In this case variation of the extent
of lengthwise movement of the link I and motion of the rocking shaft H, of the
feeding mechanism to vary the length of stitch is effected by adjusting the position of
the stud in the slot nearer or farther from the pivot by means of the screw m
and the stitch regulating nut n which is connected to the link I, by an auxiliary
link n².
2
end
on the
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 following instrumentalities, viz; a rotating shaft
provided with an elbow or incline and a cam; a needle bar and connections between it
and the said shaft to reciprocate the needle-bar; a vertically placed rock-shaft having
arms at or near one end to embrace the elbow of the said shaft, at or near its lower end
an arm or crank; a pivotted shuttle carrying hub or lever and a link to connect it to
the said arm or crank at the lower end of the said rock-shaft; a feed-bar; a rock-shaft
to which it is jointed; a link connected to an arm of the said rock-shaft and extended
upwardly into the arm of the machine near the said rotating-shaft; and a slotted guide

page_text: and stud whereby the extent of the longitudinal throw of the said link may be varied
to turn the rocking-shaft of the feeding mechanism for a greater or less distance to
alter the extent of the reciprocating movement of the feeding bar and consequently
the length of the stitch and a cam surface to effect the rising and lowering of the
feed-bar, the said parts being constructed and combined to operate all substantially
as described..
2. In a sewing machine the combination with a horizontal rock shaft for imparting
the longitudinal feeding movement to the feed bar and a link or lever connected at its
lower end to said rock shaft and having forked arms at its upper end acted on by a cam
on the main shaft of an adjustable guide block mounted on the bracket arm of the
machine and having in it a slot or groove to receive a stud on the link, and an adjusting
screw for changing the inclination of said slot or groove whereby the longitudinal
movement of the link may be varied to vary the length of stitch, substantially as
described.
3. In a sewing machine, the combination with a link connected to and operating a
horizontal rock shaft for imparting longitudinal feeding movement to the feed bar, of
a forked lever pivotted in the bracket arm of the machine and provided with a slot
whereinto a stud or slide on the end of the link, is fitted and an adjusting screw for
changing the position of said pin or slide in the slot and thereby varying the
longitudinal movement of the link and altering the length of stitch, substantially as
described.