Improvement in Sewing Machines.
Year: 1899

page_text: Improvement in Sewing Machines.
We, BENSON'S PATENT HEMSTITCHING MACHINE COMPANY, Limited, JOHN
ARTHUR BATCHELOR and FRANCIS EARNEST HALL, Sewing Machine Mechanics,
all of 32, Cloth Fair, London, E.C., do hereby declare the nature of this inven-
tion to be as follows:
This invention relates to the feed mechanism of sewing machines, and more
particularly to top feed mechanism of machines having a frame and main driv-
ing shaft arranged as shown in the Specification of Benson's Patent No. 5903 of
1893. In the accompanying drawings Fig. 1 is a side view, and Fig. 2 an end
view of a feed mechanism embodying our invention, Fig. 3 shows a detail of
construction.
The cloth presser or presser foot a which shifts the cloth is adapted to move
both horizontally and vertically. The vertical motion produced in the usual
manner by causing the presser foot to slide up and down in a vertical guide
piece placed at the head of the machine, while the horizontal motion is pro-
duced by the mechanism hereafter, described. Both motions are derived from a
grooved disc or came which is rigidly fixed to a spur wheel d set in motion
from the main driving shaft e by means of another spur wheel commonly used
in machines of the Thomas and Benson type and therefore not shown in the
drawing.
The lifting of the presser foot is produced by a crank pin c¹ fixed to the
disc e, and by intermediate mechanism, of the kind employed in Benson's
patent machines. This mechanism does not form part of the present invention,
and is therefore not shown in the drawing.
The horizontal motion of the presser foot is produced by a specially shaped
groove, formed in the circumference of the disc or cam c, through the inter-
mediary of a two-armed lever f, having at its lower end a friction roller and
at the upper end a sliding block: a slotted lever g, in which slides the said
block; a horizontal shaft h; and a lever i adapted to act on the presser foot a by
means of a sliding block and a vertical slot.
Fig. 3 represents the circumference of the grooved disc c laid out into a
plane, so as to show the shape of the slot c
Various other devices may, however, be employed for producing a positive
to-and-fro motion of the presser foot a, from the cam or driving shaft of the
machine, instead of depending on a spring for the return motion, as is the case
in other machines, which spring becomes unreliable and inefficient, if the
machine has to work at high speed.
The 1000
FAIRFAX & WETTER.
Agents for the Applicants.

page_text: -
We, BENSON'S PATENT HEMSTITCHING MACHINE COMPANY, Limited, Manufac-
turers, Joux ARTHUR BATCHELOR and FRANCIS ERNEST HALL, Sewing Machine
Mechanics, all of 32, Cloth Fair, in the City of London, 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 the feed mechanism of sewing machines, and more
particularly to top feed mechanism of the type described and shown in the
Specification of Benson's English Patent No. 5903 of 1893. In these machines
the presser foot receives motion from two distinct sets of mechanism, one of
which produces the forward motion and the other the down motion of the same,
while the motions in the opposite directions, viz., the backward and the up
motion are produced by springs.
The two sets of mechanism mentioned above are driven from a cam which
turns on an axis parallel to the driving shaft of the machine.
If such a machine works at a great speed, the cloth feed becomes unreliable
and irregular, because the horizontal forward and backward motion of the
presser foot depends partly on a spring. The present improvement has for its
object, to render such machines suitable for high speed by imparting to the
presser food a positive forward and backward motion.
In the drawings filed with the Provisional Specification, Fig. 1 is a side view
and Fig. 2 an end view of a feed mechanism embodying our invention, while
Fig. 3 shows a detail of construction.
The cloth presser a and presser foot which shifts the cloth is adapted to move both
horizontally and vertically. The vertical motion is produced in the usual man-
ner by causing the presser foot to slide up and down in a vertical guide piece b
placed at the head of the machine, while the horizontal motion is produced by
the mechanism hereafter described. Both motions are derived from a grooved
disc or cam c which is rigidly fixed to a spur wheel set in motion from the
main driving shaft e by means of another spur wheel commonly used in machines
of the Thomas and Benson type, and therefore only indicated by dotted lines.
The lifting of the presser foot is produced by a crank pin el projecting from
the face of the disc e, and by intermediate mechanism of the kind employed in
Benson's patent machines. This mechanism does not form part of the part of
the present invention, and is therefore not shown in the drawing.
The horizontal motion of the presser foot is produced by a specially shaped
groove, formed in the circumference of the disc or cam c, through the inter-
mediary of a two-armed intermediate lever f. having at its lower end a friction
roller, and at its upper end a sliding block secured to the lever: a forked lever
having a longitudinal slot in which slides the said block, a horizontal shaft.
which is supported at the ends by pivotal bearings projecting from the machine
frame, and a lever i adapted to act on the presser foot by means of a sliding
block pivoted to the extremity of the lever i, and a vertical slot formed in the
presser foot a.
The rear lever g and front lever i are fixed to the shaft h and
extend downward from the same. The fulcrum of the lever f is supported in a
bracket fixed to the machine frame. Fig. 3 represents the circumference of the
grooved disc e laid out into a plane, so as to show the shape of the groove c². As
the groove has two lateral bends or deviations, each revolution of the cam e will
produce two forward and two backward motions of the cloth presser a.
The effective length of the lever f may he regulated by varying the position

page_text: of the sliding block, which has a set screw for securing it in the desired posi-
tion, as shown by Fig. 2. As the stroke or amplitude of oscillation
of the
lever g depends on the effective length of the lever f and the cloth feed depends
on the length of the stroke or oscillation of the presser foot in a horizontal
direction, the cloth feed may be regulated by varying the position of the sliding
block on the lever f.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, we declare that
what we claim is:-
1. In top feed mechanism of sewing machines having a horizontal driving
shaft situated at the rear of the machine, the combination of a vertically and
horizontally moveable cloth presser and means for imparting to it a vertical
motion, with a grooved disc geared together with the driving shaft and adapted
to be turned on its axis by the same, a horizontal rocking shaft secured to the
upper part of the machine frame at a right angle to the driving shaft, a lever
extending downward from the front part of the rocking shaft and connected at
its free end with the cloth presser, so as to impart a horizontal to and fro
motion to the same, a lever mounted on the rear part of the rocking shaft, a
two-armed intermediate lever mounted on the side of the machine frame between
the grooved disc and the rocking lever, one arm of the said intermediate lever
projecting with its extremity into the groove of the grooved disc, while the other
arm is adapted to transmit motion to the rear arm of the rocking lever, sub-
stantially as described.
o
2. In sewing machines having top feed mechanism of the type described in
Benson's Specification No. 5903 of 1893, the method and means for imparting
the horizontal motion to the presser foot, substantially as described.
Dated this 15th day of February 1900
FAIRFAX & WETTER,
Agents for the Applicants.