Improvements in Sewing Machines."
Year: 1897

page_text: Date of Application, 12th Oct., 1897-Accepted, 11th Dec., 1897
"6
COMPLETE SPECIFICATION.
'Improvements in Sewing Machines."
We, WILLIAM HARRIS BOYER, of 47 Leonard Street, New York City Mechanician
and THE AMERICAN SPECIAL MACHINE Co. LTD., Wool Exchange, Bldg., Corner
West Broadway and Franklin Streets, New York City, U.S.A., 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:-
Our invention relates to improvements in sewing machines and particularly to that
class in which a double chain stitch is formed by means of an eye pointed needle
and a cooperating thread carrying looper, and our object is to provide a machine
of the class referred to which will be comparatively simple in construction yet
very effective in operation and capable of running at a very high speed. The
present invention has been specially designed for use upon a machine in which
the feed moves in a path longitudinally of the bed plate of the machine.
The invention in one of its presentations comprises a main shaft formed at one
portion with an inclined crank and having also an eccentric combined with a
looper supporting shaft extending longitudinally of the bed plate of the machine
and connected at its rear end with what may be called a "looper operating frame
or rocking fork" having wings or flanges embracing the inclined crank, and hav-
ing rearward of the wings or flanges an opening constituting a yoke in which
the eccentric on the main shaft works and thus, in the rotation of the main shaft,
a rocking and reciprocating movement is given to the looper supporting shaft.
The invention further includes various matters hereinafter described and set forth
in the appended claims, the above brief statement being intended simply as a
general description of the character of the machine and not in any respect meant
as a limitation upon the claims.
In the accompanying drawings which illustrate the invention.
Figure 1 is a sectional plan view of a sewing machine embodying the invention;
Figure 2 is a side view of the looper fork crank hearing;
Figure 3 is an end view of the looper fork;
Figure 4 is a side elevation of my invention.
In these drawings A represents the standard of the machine having a suitable
base to be secured to the bench or table. This standard encloses the greater por-
tion of the operating mechanism and has extending at a right angle to it a casing B
forming the bed plate of the sewing machine, this bed plate being herein shown
as bylindrical in shape and containing the looper and feed dog with their operating
parts. The main shaft C is supported in bearings in the standard A and carries
on one end a belt wheel which receives power from any suitable source. One of
the bearings for the main shaft C is composed of a removable sleeve D secured in
the wall of the standard and adapted to be held in place by the screws a, this
bearing being made removable and adjustable because of the peculiar shape of the
main shaft which is hereinafter referred to. This shaft at the point is bent
out of its plane forming the inclined crank which rotates between the wings
or flanges d of the rocking fork E provided with an opening c (see fig. 3) in the
rear, thus forming a yoke and within this yoke an eccentric F on the main shaft

page_text: works. This rocking fork, termed in the claims a looper mocking frame, is pro-
viled with the projecting tubular portion of forming a clamp in which is secured,
by suitable adjusting screws g, the rear end of a shaft G which extends throughout
almost the entire length of the bed plate or cusing B and carries on its outer end
loopers, herein shown as two in number and co-operating with needles set in
a vertical plane oblique to the line of feed, which, in this instance is longitudinal
of the casing or bed plate. It will be seen by the construction of the frame E,
inelined crank c and eccentric F, that in the rotation of the main shaft a rucking
and reciprocating movement is given to the looper supporting shaft G, the rocking
movement being the movement which takes the loop of needle thread and the
reciprocating movement that which enables the loopers to avoid the needles. By
turning the looper supporting shaft G in the clamp it will be seen that the posi
tion of the loopers with respect to the needles may be varied and thus the time
in which the loopers take the needle Imps may be changed at will. In Figure 4
we have shown a looper thread take up mechanism, in which the needle operating
lever L is provided with a downward extension having a forked piece & attached
thereto with a guiding eye on each arm of the fork, a stationary cam / adjustably
secured to the machine frame by means of a slotted piece and screws
and interseeling the horizontal plane of the guiding eyes with a nipping
device m secured also to the machine frame, said nipping device including
a spring plate adapted to be engaged in the movement of the needle lever by
a screwed projection thereon whereby the plate is compressed and the thread
gripped to allow the slack take up to act without pulling off thread from the
spools. It will be understood, however, that we do not wish to be limited to this
construction as any other suitable take up arrangement may be used in this
machine.
12
The feed dog carying bar is shown at H and is arranged above the looper shaft.
To it is pivotally connected at 1 the feed lever connecting rod K, this connecting
rod at its rear end being provided with a sleeve or collar 1. fitting over a bolt M
adjustable up and down in a curved upright slotted piece N forming a part of the
feed rocking sleeve or crank 0 supported on cones o connected to the feed fork p
embracing the eccentric Pon the main shaft. For raising or lowering the connee-
tion between the feed connecting rod and the fork arm we provide a vertical
screw by the movement of which the point of connection of the feed lever rod
with the upright slotted arm may be adjusted up and down to vary the amount of
throw of the feed lever. The upwaad and downward movement of the feed lever
is given by means of a cam arranged near the outer end of the looper supporting
shaft. The feed lever H slides in the bearing on the upper part of the standard
in which the looper shaft has its bearing.
Verious minor modifications and changes in the construction of this device may
he made without departing from the spirit of our invention. Furthermore, it will
be understood that we do not wish to limit ourselves to the precise details of con-
struction herein shown and described, as many modifications and changes in the
construction of the various parts may be made without departing from the spirit
of our invention.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same to be performed, we declare that what we
claim is:-
1. A sewing machine comprising a main shaft, a looper supporting shaft extend-
ing at a right angle thereto, a suitable bed plate enclosing the same, a feeding
device working longitudinally thereof, a frame to which one end of the looper
supporting shaft is connected, having wings and a yoke, said main shaft having
a crank working between said wings to vibrate the looper shaft and an eccentric
working in the yoke to give longitudinal sliding movement to the looper sup-
porting shaft: substantially as described.
2. In a sewing machine, a main shaft formed at one portion with an inclined

page_text: crank and having also an eccentric combined with a looper supporting shaft
extending longitudinally of the bed plate of the machine, a looper rocking frame
to which the looper supporting shaft is connected at its rear end and having wings
embracing the inclined crank and having rearward of the wings an opening con-
stituting a yoke in which the eccentric on the main shaft works, whereby in the
rotation of the main shaft a rocking and reciprocating movement is given to the
looper supporting shaft: substantially as described.
In a sewing machine the combination with the needle and operating mech-
anism, of a looper carrier comprising a shaft extending lengthwise of the machine
bed plate and carrying near its outer end a looper, and having at its rear end
wings and a yoke, and a rotating shaft having means for engaging the yoke and
wings substantially as described.
4. A sewing machine comprising a bed plate and stitch forming mechanism,
the latter including a sliding and rocking looper carrier, comprising a long shaft
extending longitudinally of the bed plate and carrying the looper and having
the rocking frame at the other end provided with a yoke: substantially as described.
5. In a sewing machine having a cylindrical bed plate, a transverse main shaft,
having a crank and an eccentric thereon, a looper carrier having wings and a
rigid portion
yoke engaging respectively the crank and eccentric, and having
extending longitudinally of the bed plate, and a looper secured thereto, substain-
tially as described.
al
6. In a sewing machine a main shaft, having a crank and an eccentric thereon,
a looper rocking frame having wings and a yoke engaging respectively the crapk
and eccentric, and having a laterally extending tubular portion, and a looper
supporting shaft carrying a looper and removably and adjustably secured within
said tubular portion; substantially as described.
7. In a sewing machine a rotating shaft having suitable supporting bearings
and having an inclined crank and an eccentric, a looper carrier haking wings and
a yoke, which engage respectively the inclined crank and eccentric and having
a rigid laterally projecting portion on one side only and a looper secured to said
rigid projecting portion; substantially as described.
8. In a sewing machine, the main shaft, the looper supporting shaft with con-
nections between the two for reciprocating and oscillating the latter, a feed dog
carrying bar, a rocking frame to which the same is attached, and a cam recipro-
cating and oscillating with the looper supporting shaft and engaging the feed
dog carrying bar for raising the same, and means for oscillating the said rocking
frame substantially as described.
9. A sewing machine comprising a rear transverse standard, a main shaft sup-
ported thereon, a feed rocking frame also entirely supported within said standard,
a looper rocking frame within the same and operatively connected to the main
shaft, a bed plate or casing extending at right angles to the rear standard and
enclosing a feed dog carrying bar and a reciprocating and oscillating looper sup-
porting shaft which, at their rear ends, extend into the rear standard and are
operatively connected to the feed rocking frame and looper rocking frame res-
pectively; substantially as described.
10. A sewing machine comprising a driving shaft, a bed plate, and a looper
operating device comprising a shaft extending longitudinally of the bed plate and
having at its inner end a frame, an inclined crank operatively engaging the frame
to give an oscillating motion to the shaft and means for reciprocating said shaft;
substantially as described.
11. A sewing machine comprising a driving shaft, a looper supporting shaft
journaled in bearings on the machine frame and having a reciprocatory and
oscillatory motion, a frame to which the looper supporting shaft is attached, and
a rigid crank and eccentric connection between the rocking frame and the driving
shaft substantially as described.
12. A sewing machine comprising a driving shaft, a bed plate and a looper
operating device comprising a shaft extending longitudinally of the casing, and

page_text: having at its inner end a frame, and means carried on the driving shaft directly
engaging said frame to give said oscillatory and reciprocating movements; sub-
stantially as described.
13. In the herein described sewing machine, the driving shaft provided with
the rigid integral inclined crank and eccentric, both arranged between the bear-
ings thereof, the looper supporting mechanism having a rocking frame connected
with the crank and with the eccentric for reciprocating and oscillating the looper;
substantially as described.
14. A sewing machine comprising a driving shaft, a bed plate and a looper
operating device comprising a shaft extending longitudinally of the bed plate
and having at its inner end a frame, and an inclined crank and eccentric opera-
tively engaging the frame, and operated from the driving shaft: substantially
as described.
Dated this 11th day of October 1897.
H. D. FITZPATRICK,
70 Wellington Street, Glasgow, Agent.