Improvements in Feeding Mechanism for Sewing Machines.
Year: 1897

page_text: Date of Application, 19th Jan., 1897-Accepted, 1st May, 1897
[Communicated from abroad by THE SINGER MANUFACTURING COMPANY,
of New York. in the United States of America, Sewing Machine
Manufacturers.]
Improvements in Feeding Mechanism for 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 relates to that form of sewing machine feeding mechanism which
has long been used in the well-known "Singer" lockstitch machines and in which
the forward and backward movements of the feed-bar are imparted thereto from
a rock-shaft beneath the work-plate of the machine operated from a cam on a
rotating driving shaft journalled in the upper part of the bracket-arm through a link
which is forked at its upper end to embrace said cam, and jointed at its lower end
to an arm at the rear end of said rock-shaft, said link co-operating with a second
link pivoted to the operating link and to a bell-crank regulating-lever, thereby
forming a toggle the relative position of the parts of which, as determined by the
position of the said regulating-lever, determining the lengths of the movements of
the said rock-shaft, and consequently the lengths of the horizontal movements of
the feed-bar and feed-dog.
The object of the present invention is to improve the feeding mechanism referred
to by a construction which will adapt the feed to be instantly reversed without
stopping the machine, so that in finishing the end of a seam, or at any other time,
a few backward stitches may be made; the construction being such that the feed,
when thus reversed, will have the same length of movement as the forward feed ;
and the parts may then be restored to their normal operative positions with the
forward feed of the same length as-at first. I effect this object by so constructing
and arranging the parts that the regulating-lever may be sufficiently varied in
position as to cause the link connecting said lever with the operating link to vibrate
on one side or the other of a central line running from the centre of the driving
shaft to the point of connection of the operating link with the arm of the feed-
operating rock-shaft, and providing said regulating lever with a lateral projection
having an obtuse V-shaped recess or fork to receive the tapered or rounded end
of a controlling screw which serves as an adjustable abutment to limit the move-
ments of the regulating-lever when the latter is moved in either direction to cause
the feed to move the work either forward or backward.
In the accompanying drawings Fig. 1 is a sectional side view of a portion of
a "Singer" sewing machine embodying my invention.. Fig. 2 is a vertical section
through the arm of the same on line 2-2 Fig. 1.
A denotes a portion of the arm of the machine, and B the rotating driving
shaft journalled in the upper part of said arm and provided with the cam b embraced
by the fork c, at the upper end of the link C which latter is jointed at its lower
end to an arm d of the feed-operating rock-shaft D. E is the feed-bar pivotally
connected as usual to an arm or arms d¹ at the forward end of the shaft D.
F is the bell-crank feed regulating lever connected by the link g with the link C,
as usual, said lever being provided near its fulcrum with a projection in which is

page_text: rined a V-shaped recess fl. Tapped in the arm A is a controlling screw / the rounded
r tapered inner end of which may, by adjusting said screw, be caused to project
more or less into said recess so that when the regulating lever is moved to change
the direction of the feed one or the other of the side walls of said recess will be
brought into contact with the end of said screw, the latter thus serving as an
adjustable abutment to limit the adjusting movements of the feed regulating-lever
in either direction.
The regulating lever F" is retained in any desired position of adjustment by a
collar on the outer arm thereof, said collar being held in frictional engagement
with segmental bearing portions a on the arm A, by a coil spring f³ interposed
between the head of a screw, forming part of the regulating lever F, and a
shoulder formed in said collar by counter boring the latter. The slot a' in the
arm or frame A, through which the outer arm of the lever F projects, is of sufficient
length to permit a greater adjustment of said lever than heretofore in machines
feeding only forward, so that by moving the said arm of said lever from the central
neutral point towards the bottom or top of said slot the feed will be caused to move
the work either forward or backward, as may be desired.
When the outer arm of the lever F is adjusted to the central neutral point
referred to the vibrations of the link g, forming part of the toggle and connecting
the regulating lever F.with the link C, will be equal on each side of a line running
from the centre of the shaft B to the centre of the point. of connection of the
said link C with the arm d of the shaft D, so that no feeding rocking movements
will be imparted to said shaft, but when said lever. F is adjusted so as to cause
vibrating movements of the said link g to be on one side or the other of the central
line referred to feeding rocking movements will be imparted to said shaft, and these
rocking movements will be so timed, relative to the usual vertical movements of
the feed bar, so as to cause the work to be moved either forward or backward, as
the outer arm of the lever F may be moved toward the bottom. or.top of the
slot a', as heretofore stated; the adjusting movements of the said lever in either
direction being controlled by the position of adjustment of the screw into contact
with the point of which the side, walls of the V-shaped recess f₁ of the lever F
come when the said lever is adjusted to change the direction of the feed.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is―
In a sewing machine employing a toggle feed, the combination with the feed-bar,
the link C operatively connected with said feed-bar, and means for operating said
link, of the regulating lever F. having a part provided with a V-shaped recess,
as, an adjustable abutment, as screw h, projecting, into said recess to limit the
adjusting movement of said lever in either direction, the link g joining said lever
to the operating link C, and means for retaining said .lever. F in any position to
which it may be moved..
Dated this 18th day of Januaro 1907