Year: 1885

page_text: I, ALEXANDER ANDERSON, Manager of the Singer Manufacturing Company's
Works Kilbowie, Dumbartonshire, do hereby declare the nature of this invention,
a communication to me from abroad by The Singer Manufacturing Company of
New York in the United States of America, Sewing Machine Manufacturers, and
in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:-
This invention which relates to sewing machines has for its objects (1) to produce
a light shuttle operating mechanism of such construction that the tendency of the
shuttle lever to spring when in operation and the vibratory jar of the machine
incidental thereto will be almost entirely avoided, and (2) to provide simple and
effective feeding mechanism in which the side thrust of the feed lever on the feed
bar incidental to some feeds now in use is avoided and friction is thereby lessened.
In the improved shuttle operating mechanism I pivot the shuttle lever to the
bed plate of the machine between the vertical driving shaft and the shuttle race
and I operate said lever from the crank on said shaft by a link and intermediate
lever. The feed bar of the improved feed operating mechanism rests on and is
lifted by a horizontal arm of a rock shaft the latter having a vertical arm against
which the forward end of the feed lever impinges. The said lever is provided at
its rear end with a yoke having two offset portions embracing two cams on the
vertical countershaft of the machine. One of said cams has but a very small throw
and serves to give a slight end wise movement to the feed lever to vibrate the rock
shaft and thus lift the feed bar, and the other cam has sufficient throw to give the
feed lever its usual vibratory movements to move the feed bar forward and back.
The feed lever is pivoted by a fulcrum block carried on an adjusting slide movable
in a groove formed in the underside of the bed plate of the machine.
In the accompanying drawings which illustrate my invention figure 1, is a
sectional elevation of a sewing machine embodying my improvements; figure 2, is
a partial longitudinal section of the same through the feeding mechanisin; figure 3,
is an inverted plan of the machine; figure 4, is an end view of the bed "plate.

page_text: reversed; and figure o is a detail view showing the spring for lowering the
feed bar.
In these drawings A, indicates the bed plate of the machine and B, the bracket
arm thereof. Journaled in the upper portion of the bracket arm is the horizontal
driving shaft C, having a bevel gear c, meshing with a similar gear d on the upper
end of a vertical countershaft D, the latter having at its lower end a crank E.
F is the shuttle lever which is pivoted on a stud a, attached to the bed plate
between the vertical shaft D, and the shuttle race a¹, said lever being provided at
its forward end with the usual shuttle carrier fadapted to support and drive the
shuttle e G is a bell crank or driving lever pivoted on a stud a attached to the
bed plate between the pivotal point of the shuttle lever and the shuttle race.
arm g of said bell crank lever is forked to embrace a stud f¹ on the shuttle lever
and the other arın g¹ thereof is connected by a link or pitman H with the crank E.
The shuttle and bell crank levers have different radii and a loose connection
between them is afforded by the slotted or forked arm g of the latter.
One
It is necessary for the shuttle carrier to vibrate closely to the under side of the
bed plate so that the shuttle may be as near as possible to the needle and the work,
and to enable the shuttle lever to swing across or beneath the pivot pin or stud of
the bell crank or driving lever and to carry on its upper side the stud f¹, for
engagement with the latter lever the shuttle lever is provided with inclines or
bends ff so that the rear end of the latter lever is at a suitable distance below
the bed plate.
Motion being imparted to the driving and vertical shafts, the crank on the lower
end of the latter, being connected by the link H to the bell crank lever G, will
cause said lever and the shuttle lever to vibrate, as will be readily understood.
The shuttle lever, being pivoted between the vertical shaft and the shuttle race, is
comparatively short, and the power being applied thereto between the fulcrum and
the forward end of the lever it is very rigid in operation; and thus the objection
incidental to shuttle levers as ordinarily constructed, in which the "spring" varies
greatly between slow and fast speeds, is nearly or wholly avoided. In fact my
shuttle lever, constructed and operated as hereinbefore described, really amounts to
a shuttle carrier having a smooth and easy reciprocating movement with very little
vibratory jar, even at very high speeds.
By arranging the driving lever so that its fulcrum is between the fulcrum of the
shuttle lever and the shuttle race, or in other words, within the space bounded by
lines drawn from the shuttle-lever pivot-pin to the ends of the shuttle-race, the
driving lever is placed more closely to the shuttle-lever and the movements of the
former are more directly applied to the latter than would otherwise be possible;
thus securing a compact arrangement of these parts which is desirable in a light
running, high speed machine.
On the shaft D, just above the crank E, are two feed cams i, i¹, working within
a yoke J, on the rear end of the feed lever J', said yoke having two offset portions
each of which engages one of the said cams. One of said offset portions is formed
by bars j, extending transversely of the machine and between these transverse bars
works the feed cam i, which has but a very small throw so as to impart but a
slight end wise movement to the feed lever. The larger feed cam i¹, works between
the bars extending longitudinally, of the machine and thus serves to impart the
usual vibratory or feeding movements to the feed lever.
K is a rock shaft, herein shown as being pivoted on centre-screws 7, passing
through lugs depending from the bed plate A. The rock shaft K is provided
with a horizontal arm k on which the feed bar M rests, and with a vertical arm k¹
engaged by the forward end of the feed lever J¹, said end being preferably slightly
rounded as shown, to lessen frictional contact with the arm k, as the lever vibrates
in feeding. The arms of the rock shaft are at opposite ends of said shaft, as shown
in figure 3. The feed lever engages the feed bar M by a slot in the latter which
permits said bar to move vertically independently of the feed lever, while the latter

page_text: fits snugly in said slot horizontally so as to impart positive horizontal or feeding
movements to said bar in both directions.
The feed lever is supported by a small lug or bracket n attached to a rib n¹ on
the bed plate and said lever has its fulcrum in a block o, swivelled in the forward
end of a feed regulating slide P adjustably attached to the bed plate in the
usual manner by a set screw o¹. The forward end of the slide P, in which the
block o, is swivelled is squared and fits snugly in a groove or guiding way, beneath
the bed plate, formed by the ribs n¹ and n
When motion is imparted to the driving and vertical shafts, the feed cams on the
latter shaft working in the yoke of the feed lever, will impart positive endwise or
longitudinal and vibratory movements to said lever, the cams being arranged so
that said endwise and vibratory movements will alternate or occur between each
other. The outward thrust of the feed lever against the arm of the rock shaft K
will turn said shaft slightly on its axis and thus cause its arm k to lift the feed bar.
The feed lever then swings to move said bar forward in feeding; the backward
endwise, movement of said lever then occurs to permit the feed bar to descend,
and said lever then swings reversely to return the feed bar to its first position.
Thus a strong and easily working feed will be produced with a very slight end wise
movement on the feed lever, and as the feed bar rests on an arm of the rockshaft
side thrust on the said bar is avoided.
In the construction shown, the downward movements of the feed bar may be
effected by gravity assisted, in operation, by the pressure of the presser foot but
a spring as m for lowering the feed bar will preferably be employed and said
spring will also hold the feed bar back against the feed lever if there is any lost
motion between these parts.
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 bed plate, bracket arm, hori-
zontal and vertical shafts and their gearing, of a shuttle-lever pivoted at its rear
end to the said hed-plate between the said vertical shaft and the shuttle race,
a driving lever having its fulcrum between the fulcrum of the shuttle-lever and
the said shuttle race and loosely connected with said shuttle lever between the
fulcrum of the latter and the shuttle carrier, and connections between said vertical
shaft and driving lever substantially as set forth.
2. In a sewing machine the combination with the bed plate, bracket arm, hori-
zontal and vertical shafts and their gearing, of a shuttle lever pivoted at its rear
end to said bed plate between said vertical shaft and the shuttle race, a bell crank
lever loosely connected with said shuttle lever, a crank on said vertical shaft and
a link or pitman connecting the said crank and the bell-crank lever, substantially
as set forth.
3. In a sewing machine the combination with the bed plate thereof, of a
shuttle lever pivoted thereto and having a stud on its upper side and inclines or
bends, a driving lever loosely connected to said shuttle lever and having its pivotal.
point forward of the pivotal point of the shuttle lever, and mechanism for operating
said driving lever substantially as set forth.
4. In a sewing machine the combination with the bed plate, bracket-arm, hori-
zontal and vertical shafts and their gearing, of a shuttle lever pivoted at its rear
end to said bed-plate and having a stud on its upper side and inclines or bends,
a bell-crank driving lever forked to embrace said stud and pivoted forward of the
pivotal point of the shuttle lever, a crank on said vertical shaft and a link or
pitman connecting the said crank and the said bell-crank lever, substantially as
set forth.
5. In a sewing machine the combination with the bed plate of a shuttle lever
pivoted at its rear end to said bed plate, a bell-crank driving lever loosely connected

page_text: with said shuttle lever between the pivotal point of the latter and the shuttle
carrier, and mechanism for operating said bell crank lever substantially as set
forth.
6. In a sewing machine the combination with a two-armed rock-shaft, of a feed
bar resting on one of the arms of said shaft, a feed lever engaging the other of
said arms and mechanism for reciprocating and vibrating said feed lever substan-
tially as set forth.
7. In a sewing machine the combination with a rock-shaft, having horizontal
and vertical arms, of a feed bar engaging said horizontal arm, a feed lever engaging
said vertical arm and having at its rear end a yoke, two cams working within said
yoke and means for operating said cams, substantially as set forth.
8. In a sewing machine the combination with the bed-plate, bracket-arm and
horizontal and vertical shafts and their gearing, of a rock-shaft having horizontal
and vertical arms, a feed bar resting on said horizontal arm, a feed lever engaging
said vertical arm and having at its rear end a yoke with two offset portions, and
two cams on said vertical shaft working within said yoke, substantially as set
forth.
Dated this Coun
1