Improvements in Chain-stitch Sewing-machines.
Year: 1894

page_text: Date of Application, 17th Oct., 1894-Accepted, 13th Apr., 1895
CUMI LETE SPECIFICATION.
Improvements in Chain-stitch Sewing-machines.
I, FRIEDRICH REINHOLD BRAUER, of Chemnitz, Saxony, in the Empire of
Germany, Manufacturer, do hereby declare the nature of my said 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 a device in connection with chain-stitch sewing machines
by means of which fancy seams or work composed of variously coloured threads
may be made by employing several needles each threaded with a single-colored
thread.
In order that my invention may be clearly understood I will now describe same
O with reference to the accompanying drawings in which :
Fig. 1 is a side view
Fig. 2 a front view and
Fig. 7 a plan view of the sewing machine.
Figs. 3, 4, 5 & 6 are modifications of the cam with ratchet wheel for horizontally
reciprocating a frame mounted in the machine.
On the frame c are mounted two independently-operating needle-bars f, f¹,
between and in front of which is situated a bar d (Figs. 1 2 and 7) formed like a
needle-bar, since same is used as such when making triple-threaded chain-stitches.
Two catches e, e¹ are pivotally connected to the needle-bars ƒ, ƒ¹.
C
The horizontally sliding frame c is operated by a cam b in such manner that, as
the bar d ascends, the sliding movement commences and continues until said bar
attains its uppermost position. A needle is made to penetrate the material to be
worked, by the catch e engaging underneath a cross-head o on the bar d, the
needle-bar thus following the movement of the bar d until the frame c changes its
position, that is, until it retreats from the bar d; the needle bar f¹ is then caused
to make a stitch in the same manner i.e. by the catch e¹ engaging with the
cross-head o of the bar d.
When the rod has completed one movement (i.e. has ascended and descended)
the ratchet-wheel a is rotated to the extent of one tooth and the cam fixed to said
ratchet wheel is simultaneously advanced to the same extent in the direction of the
arrow (Fig. 2).
By the action above described, double-threaded seams and, when the bar d is
simultaneously employed, triple-threaded seams are made.
By employing the cam shown in Fig. 3, each needle makes three stitches at each
revolution of the ratchet wheel a, and with the cam shown in Fig. 4, eight stitches
cach needle making four alternate stitches. With the cam shown in Fig. 5 one
needle makes two successive stitches and the other, five successive stitches; whereas
with the cam shown in Fig. 6, the bar d is also brought into operation, and one
needle makes five, the second one, and the third, three stitches at each revolution of
the wheel a.
By employing the cam shown in Fig. 2, the one needle makes one stitch and the
other three stitches at each revolution. If a triple-threaded seam is to be made,
the bar d stitches uninterruptedly, without being affected by the operation or
movement of the needle bars f, f¹.
It will be evident that all the needles cannot make a stitch at the same moment.
When the bar d commences to ascend and descend, an oscillating movement is
mparted to the catch e, and, as said bar d ascends, the wheel a is rotated to the
extent of one tooth. The resulting part-rotation of the cam b forces the frame c
[Price 8d 1

page_text: towards the left. The bar d however does not participate in such movement and
consequently it engages with the bar f by means of the cross-head o, the bar f
being thus caused to make a stitch. Iminediately the needle leaves the material,
the frame c moves towards the right, the cross head o on the ascent of the bar d,
forces the catch el away,
said catch e' after the bar d has reached its uppermost
position, returns to its former position and, when the bar d descends again, takes
along with it, the needle-bar f¹, thus causing same to make a stitch.
The needle bar d, which is caused to continuously ascend and descend by the
action of the cam b, through the medium of a lever, 9, alternately carries with it
(by means of the catches e and e¹ respectively) the needle bars fand f¹, these bars f
and thus descend and stitch alternately.
When it is desired to make a triple-threaded stitch, the needle-bar d, is also
furnished with a needle. The operation being the same, it will be evident that two
consecutive needles will stitch simultaneously i.e. first the needle bar f together
with the bar d and then the bar f¹ together with the bar d. In other words, the
bard stitches uninterruptedly, alternately carrying with it the bars f and f¹
respectively, according to the position of the reciprocating frame c.
The ratchet a, is an ordinary toothed wheel and is rotated to the extent of one
tooth by the action of a spring controlled pawl h, connected to the lever 9, above
mentioned by some suitable means such as by rod g', the cam b, being simultaneously
advanced to a like degree.
The chain stitches are produced in the following manner,- -When one of the
needles has descended and pierced the material a loop is formed underneath the
stitch-plate and before this needle ascends, i.e. leaves the material, a finger i catches
in said loop and holds same until the needle ascends and returns again to make a
further stitch. This second stitch passes through the loop already formed and, at
the same moment, the finger is released from said loop and catches in the newly-
formed loop, holding same until the needle returns and makes a further stitch.
When two needles stitch simultaneously, the finger catches in both loops, the
operation being otherwise exactly the same as with the single-stitch above described.
The lever g, and pawl h, and the finger i, are not essential features of the
invention and in fact, may be variously arranged or other arrangements may be
employed according to circumstances.
It will be evident that many other forms of cams may be employed in connection
with my improved device and that the number of teeth in the ratchet wheel a, may
be varied at will, so that various kinds of fancy seams or work composed of mixed
threads may be made and that the needle bars may be caused to operate in any
desired order or succession, without departing from the spirit of this invention.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a chain-stitch sewing machine a device for making fancy seams or fancy
work composed of variously colored threads by using needles threaded with single-
colored thread substantially as described and shown in the drawing.
2. An improved device for chain-stitch sewing machines for making fancy seams
composed of mixed threads, consisting of two needle-bars (f, f³) mounted on the
reciprocating frame (c) and a vertically operating bar (d) formed as needle bar
arranged between and in front of same in such manner that during the ascending
and descending motion of said bar (d) its cross-head (o) alternately engages with
each of the needle-bars (f, f¹) and causes same to make a stitch, substantially as
described and shown in the drawing.
3. In combination with the device for making fancy seams composed of mixed
threads as described in Claims 1 and 2, catches (e, e¹) pivotally mounted on the
needle-bars (f, f¹) and laterally movable on the ascent of the bar (d) an alternate
coupling with the bars (f,f¹) being effected immediately the cross-head (o) reaches
its upper position, substantially as described and shown in the drawing.

page_text: 4. In combination with the device for making fancy seams, composed ot.mixed
threads, as described in Claims 1, 2 and 3 the means for reciprocating the frame (c)
consisting of a cam (6) secured to a ratchet wheel (a), substantially as described
and shown in the drawing.
Contabar 1894
PHILIP M. JUSTICE,
Associate Agent.