IMPROVEMENTS IN SEWING MACHINES
Year: 1876

page_text: LETTERS PATENT to John Mountain, of Birmingham, in the County of
Warwick, Machinist, for the Invention of "IMPROVEMENTS IN SEWING
MACHINES."
Sealed the 21st November 1876, and dated the 4th September 1876.
PROVISIONAL SPECIFICATION left by.the said John Mountain at the Office
of the Commissioners of Patents on the 4th September 1876.
<< IM-
JOHN MOUNTAIN, of Birmingham, in the County of Warwick, Machinist.
PROVEMENTS IN SEWING MACHINES."
This Invention relates to an improvement on the machine described in the
Specification of a Patent granted to me, and bearing date September 23rd, 1874,
No. 3253, the object being to adapt the mechanism described in the said Patent to
the working, in combination of a needle and shuttle, to produce a lock stitch in
contradistinction to the single chain stitch produced under my said Patent.
According to my present Invention the rock shaft which carried the hook or
looper is made free to slide endwise in its bearings, for the purpose to be hereafter
explained, and it is fitted at its outer end with a shuttle carrier, which is caused to
oscillate in front of a vertical segment shaped race plate, and carry its shuttle to and
fro over that plate. This race plate is grooved vertically to receive the vertical
needle, which is carried by a rising and falling cranked arm, similar in operation to
that described-in my above-mentioned Specification.
As the loop of the needle thread is formed the shuttle is caused to pass through
it and to leave a thread therein to produce the well known lock stitch. The
shuttle carrier is fitted with a retaining spring, which overlies the shuttle, and
also with an eye for guiding the shuttle thread up to the work. The rock shaft
receives its axial motion through a pin projecting from the vertical slide that
carries the needle arm. This pin projects into a slotted arm keyed to the rock
shaft, and as the slide rises and falls, the pin by its play in the slot imparts an
axial motion to the rock shaft. The feed in this, as in the former instance, is effected
by a roughened rocking presser foot, but in order to prevent the work being dragged
back by the backward motion of this foot, the needle arm is provided with a
vertical spring presser, which will bear upon the work during the back motion
of the feeding presser foot, and hold it firmly on the table. This spring presser will
D..

page_text: conveniently reach the work through the slot of the feeding foot, and it will rise
out of action as the needle leaves the work to permit of the feeding action taking
place. In order to provide for the taking up of the slack of the needle thread, I
pivot on the side of the needle arm a lever, the tail end of which enters a link fixed
to the standard of the machine, while the forward end of the levor carries an eye
through which the thread passes on its passage from the bobbin to the eye of the needle.
This lever, by reason of its being pivotted to the needle arm, will, as that arm rises
to draw the needle out of the work, be tipped by the action of the stationary link
on the tail of the rising lever, and thus the thread used to form the loop for the
shuttle to pass through, will be taken up and held at tension until the needle
descends to make its next stitch. The rock shaft, carrying the shuttle driver, is
surrounded by a coiled spring which holds it back so as to keep the shuttle driver in
close proximity to the race. In order however to insert the shuttle in its carrier
as to release it therefrom the attendant must slide the rock shaft in its bearings,
and thereby force the shuttle carrier away from the race.
Rooin will thus be made
for the facile insertion into its carrier, or release therefrom of the shuttle.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Jolm Mountain in the Great Seal Patent Office on the 3rd March
1877.
JOHN MOUNTAIN, of Birmingham, in the County of Warwick, Machinist.
PROVEMENTS IN SEWING MACHINES."
"IM-
This Invention relates to an improvement on the machine described in the
Specification of a Patent granted to me, and bearing date September Twenty-third,
One thousand eight hundred and seventy-four, No. 3253, the object being to adapt
tlic mechanism described in the said Patent to the working, in combination of
a needle and shuttle, to produce a lock stitch, in contradistinction to the single
chain stitch produced under my said Patent.
In the accompanying Drawing, Fig. 1 is a side elevation of the machine, modified
so as to produce the lock stitch; Fig 2 is a front elevation of the same, and Fig. 3
is a partial sectional elavation taken in the line 1, 2, of Fig. 1.
A is the bed plate of the machine, rising from which is a standard B that forms a
guide for a vertical slide C, which is cast with or attached to a curved or cranked
needle arm C; D is the table for the work, supported by a short standard E, which is
extended Interally, as shewn at Fig 2, to form a segment shuttle race E¹. The up-
and-down motion of the needle arm is effected by means of a cam on the face of the
band wheel F, acting upon a pin or bowle carried by the vertical slide C, as des-
cribed in the Specification of my above-mentioned Patent, and from this slide is
derived the notion for the rock shaft G, which in my former Patent carried the hook
or looper. This shaft is now made free to slide endwise in its bearings for the
purpose to be hereafter explained, and it is fitted at its outer end with a shuttle
carrier H, which is caused to oscillate in front of the vertical segment shaped race E¹,
and carry its shuttle to and fro over the race. This race is grooved vertically to
receive the vertical needle c, fitted to the rising and falling cranked arm C¹.
As the loop of the needle thread is formed by the descent of the needle through
the work, and its partial return, the shuttle h, which lies between the shuttle carrier
and the race, is caused to pass through the loop and to leave a thread thorein to
produce the well known lock stitch. The shuttle carrier H is fitted with a retaining
spring h¹, which overlies the shuttle, and also with an eye h³ for guiding the
shuttle thread up to the work. The rock shaft G receives its axial motion through
a pin c¹ projecting from the vertical slide C This pin projects into a slotted arm g
(see Fig. 3) keyed to the rock shaft, and as the slide rises and falls, the pin, by its
play in the slot, imparts an axial motion to the rock shaft. The feed in this in-
•

page_text: stance, as in my former Patent, is effected by a roughened rocking presser foot I,
jointed to the lower end of a laterally rocking curved lever I', pivotted to the
standard B. In order to prevent the work from being dragged back by the back-
ward motion of the feed and presser foot, the needle arm is provided with a vertical
spring presser K, which will bear upon the work during the back motion of the
feeding presser foot, and hold it firmly on the table. This spring presser will
conveniently reach the work through the slot of the feeding foot, and it will rise
out of action as the needle leaves the work, to permit of the feeding action taking
place.
In order to provide for the taking up of the slack of the needle thread a take up
lever L is employed. This lever is pivotted to the side of the needle arm, and its
tail end enters a link fixed to the standard B, while the forward end of the lever
carries an eye through which the thread passes on its passage from the bobbin N to
the eye of the needle. This lever, by reason of its being pivotted to the needle arm,
will, as that arm rises to draw the needle out of the work, be tipped by the action
of the stationary link on the tail of the rising lever, and thus the thread, used
to form the loop for the shuttle to pass through, will be taken up and held at
tension until the needle descends to make its next stitch. The rock shaft G,
carrying the shuttle driver H, is surrounded by a coiled spring G³, which holds it
back, so as to keep the shuttle driver in close proximity to the race. In order
however to insert the shuttle in its carrier, or to release it therefrom, the attendant
must slide the rock shaft in its bearings, and thereby force the shuttle carrier away
from the race. Room will thus be made for the facile insertion into its carrier, or
release therefrom of the shuttle, when a fresh supply of shuttle thread is required.
Having now set forth the nature of my Invention of "Improvements in Sewing
Machines," and explained the manner of carrying the same into effect, I wish it to
be understood that under the above in part recited Letters Patent I claim,-
First. In combination with a needle arm carried by a vertical slide, the arrange-
ment above described for giving the traverse motion to the shuttle, and for taking
up the slack of the needle thread.
Second. The means above described for releasing the shuttle from its oscillating
carrier.
Third. The application to the needle arm of the spring presser, as and for the
purpose above described.
In witness whereof, I, the said John Mountain, have hereunto set my hand
and seal, the First day of March, in the year of our Lord One thousand
eight hundred and seventy-seven.
JOHN MOUNTAIN
6.81
JOHN MOUNTAIN (LS)