Improvements in Rotary Take-ups for Sewing-machines.
Year: 1895

page_text: COMPLETE SPECIFICATION.
Improvements in Rotary Take-ups for Sewing-machines.
I, JAMES TRIPP, of No. 724 Amsterdam Avenue, New York City, New York,
United States of America, Inventor, 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 a rotary take-up for sewing-machines, and has for its
principal objects to provide an improved construction of rotary take-up to be
located at the end of the head on the machine-arm and be carried by a shaft
mounted in said arm below the main driving-shaft; to provide improved
mechanism for operating the take-up shaft and attached rotary take-up at a
positively controlled differential or variable speed so as to properly govern the
slack of the thread in accordance with the movements of the needle; to provide
an improved construction and arrangement of the needle-bar pitman whereby its
operation from the main driving-shaft will not be affected or interfered with by
its proximity to the take-up shaft; and to provide simple and easily adjusted
connections for operating the take-up shaft and the looper or hook-shaft from the
main-driving shaft, with steadiness and in proper time movements.
The novel features and combinations of parts included in my invention will be
hereinafter more particularly described and claimed.
In the accompanying drawings-
Figure 1 is a longitudinal vertical section of a portion of a sewing-machine
provided with my improved rotary take-up and the mechanism for imparting to it
the required differential or variable rotary movetnent.
Figure 2 is an end elevation of the machine head with the rotary take-up in
position to draw upon and take up the slack of the thread.
Figure 3 is a similar view, showing the rotary take-up in position to exert a
tension on the thread for tightening the stitch.
Figure 4 is a vertical transverse section through the head of the machine, on the
line 4-4 of Figure 1.
Figure 5 is a transverse section through the rotary take-up.
Figure 6 is a perspective of the rotary take-up and a portion of its shaft.
Figure 7 is a perspective of the curved needle-bar pitman and its connection to
the main driving-shaft.
Figure 8 shows in perspective the upper portion of the link or bar for
transmitting motion from the main driving-shaft to the looper-shaft.
Figure 9 is a perspective of a slotted crank-arm on one end of the take-up
shaft and through which it derives motion from the bar or link that connects the
main driving-shaft and the looper-shaft.
Figure 10 is a view of a rotary take-up, showing a slight change in the
position of the take-up cam-lug and of the spring-arm or bar for retaining the
thread.
The reference numeral 1 designates the base-plate of a sewing machine, and
2 the bracket-arm or goose-neck having the head 3 on its end. Beneath the base
plate is journalled the looper-shaft 4; and the main driving-shaft 5 is mounted in
the horizontally extended portion of the bracket-arm 2, as usual.
On the main driving-shaft 5 is a crank Fig. 1, for connection with an eye or
coupling 7 on the upper end of a connecting bar, link or rod 8, the lower end of
which is slightly offset and provided with a pin or stud 9 to engage in a slotted

page_text: crank 10 on one end of the rotary-shaft that carries the hook or looper. By
means of the connecting rod, bar or link 8, and the slotted crank arm 10 the
rotary motion of the main driving-shaft 5 is transmitted to the hook or looper-
shaft 4 in such a manner as to provide for the proper relative time movements.
The bar or link 8 is slotted or bifurcated for passage of a horizontally arranged
guide-pin 11 mounted in the vertical portion of the bracket-arm 2, and by
providing the lower end of said bar or link with an off-setting portion 12 for
connection with the slotted crank-arm 10, as shown in Fig. 1, the main body of the
connecting rod, bar or link 8 can be so arranged that the driving power will be
exerted substantially in a direct line with the cranks 6 and 10, thus avoiding any
liability to a twisting action and providing for a steady rotation of the looper-
shaft.
In order to provide for a more convenient and satisfactory mounting of a rotary
take-up and arrange for a differential or variable rotation thereof timed to accord
with the required movements of the needle and of the hook or looper, I have
placed in the horizontal portion of the bracket-arm a longitudinally extended
take-up shaft 13 that may be suitably journalled in bearings 14, as shown in Fig. 1.
On one end of the shaft 13 is secured a crank-arm 15 having formed therein a
curved cam-slot 16, Fig. 9, for engaging a pin or stud 17, Fig. 8, carried by a rod,
bar or link 8, and through which the rotation of the driving-shaft 5 is transmitted
to the take-up shait 13 in such a manner as to give the latter a differential or
variable rotary movement. The other end of the rotary take-up shaft 13 is
extended through the head 3 and carries the rotary take-up 18 on its outer end.
The rotary take-up that I have illustrated consists, preferably, of two steel rings
or open-work discs placed parallel to each other and connected at only a single
point, but spaced apart a sufficient distance to permit the passage of the thread and
arrange for the convenient placing, on one of said discs, of two or more lugs or
cams to assist in controlling the thread. The innermost disc or ring 19, Figs. 1, 5
and 6, comprised in the take-up, is provided with spokes 20 connecting with a
central hub-plate 21 that is secured onto the outer end of the rotary take-up
shaft. On one of the spokes 20 is located a cam-shaped lug 22 that is imme-
diately concerned in the operation of taking up the slack of the thread, upon the
upward movement of the needle. For the purpose of exerting a slight tension on
the thread to aid in tightening the stitch, a cain-shaped lug 23 may be located on
another one of the spokes. The outermost disc or ring 24, of the take-up, is
connected to the disc or ring 19 at a suitable point, near their peripheries, by means
of a transverse pin or stud 25, by which the thread is carried during the differential
rotation of the take-up. The disk or ring 24 may carry a spring-arm 26 arranged
to bear lightly on the take-up cam-lug 22 and adapted to guide or retain the thread
in such manner that it will properly engage with and disengage from the take-up
lug or projection 22 and be free from any liability to fly off suddenly. A suitable
and convenient arrangement of the parts comprised in the rotary take-up is shown
in Figures 2, 3, and 6, but the spring-retaiuing arm 26, instead of crossing the
axis of the take-up, may be arranged to one side, if preferred, as shown in
Figure 10.
On the lower portion of the head 3 is a thread-guide 27 for passage of the thread
from any suitable tension device to the take-up and thence to the needle.
The needle-bar 28 is actuated from the forward end of the main driving-shaft 5
by means of a laterally curved pitman 29, Figure 7, eccentrically connected to a
disk or head 30 on the end of said shaft. As will be seen by reference to Figures 1
and 4, the concaved side or edge of the curved pitman 29 is turned toward the
adjacent rotary take-up shaft 13, so that by this construction and arrangement of
the curved pitman 29 the proximity of the forwardly extended portion of the take
up shatt will not obstruct or cause any difficulty in the required operation of the
needle-bar. The connection of the opposite ends of the curved pitman 29 to the
needle-bar 28 and shaft-head 30 may be effected, respectively, by crank-pins or
pivotal studs 31, 32, in any convenient manner.

page_text: The mounting of the rotary take-up 18 on the outer or forward end of a lengthened
take-up shaft, as 13, that is separate from the main driving-shaft 5, has the
advantage of imparting steadiness to the motions of the take-up and avoids any
tendency to twisting or crankiness. The required differential or variable rotation
of the take-up is accomplished in a simple, reliable, and positively controlled
manner through the curved cam-slot 16 of the crank-arm 15 loosely engaging the
pin or stud 17 on the rod, bar or link 8 that also connects the looper-shaft with
the main driving-shaft. Through these connections and the manner of their
arrangement a very perfect steadiness is imparted to the motions of the needle-bar,
the book or looper and the take-up, and their various operations are facilitated
with the requisite sequence in time movements.
By reason of the elliptic path described by the stud or pin 17 engaged in the
cam-slotted crank-arm 15 of the take-up shaft 13, a quick upward motion is
imparted to the portion of thread carried by the rotary take-up 18 during that part
of its rotation in which the stitch is to be tightened on descent of the needle-bar and
while a tension is being exerted on the thread by its passage over the cam-shaped
edge of the lug 23 in the position shown in Figure 3. After this quick upward
movement in the rotation of the needle-bar, and on the rise of the needle-bar, as
shown in Figure 2, the gradually changing point of engagement between the pin 17
and cam slot 16 will cause the take-up to rotate slowly while the thread falls onto
and is engaged by the take-up cam lug 22, now in the position shown in Figure 2;
which lug 22, assisted by the retaining spring 26, will hold the thread and draw
thereon in such manner as to positively control the slack until it is to be released,
as required by the hook, and by the time that the take-up has rotated to the
position indicated in Figure 10, where the thread is shown as being just about to
slip off from the cam-lug 22 of the take-up..
It will be seen that the rotary take-up and its operating mechanism are so
constructed and arranged in their several parts as to provide, in a simple and
effective manner, for the required differential or variable rotation of the take-up
so that it will positively control the thread with reference to the time movements
of the needle-bar and the hook or looper, and so that each of these parts will move
with steadiness and accuracy and without liability of obstruction.
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 :-
1. A sewing-machine take-up mechanism comprising a main driving shaft, a
take-up shaft parallel with said driving shaft and actuated therefrom with a variable
movement, two parallel discs mounted on the forward end of the take-up shaft and
connected to each other, at but a single point, by means of a pin adapted to carry
the thread, a cam-lug carried on one of said discs to control the thread, and a
spring-arm carried on the other disc and adapted to bear lightly on said cam-lug
to retain and guide the thread, substantially as described.
2. A sewing-machine take-up mechanism comprising a main driving-shaft, a
take-up shaft parallel with said driving shaft and actuated therefrom with a variable
movement, two parallel discs mounted on the forward end of the cake-up shaft and
connected to each other, at but a single point, by a pin that is adapted to also
carry the thread, a cam-lug located on one of said discs and adapted to become
engaged with and disengaged from the thread to positively control the slack, a
spring-arm supported by the other disc and arranged to bear lightly on said take-
up cam-lug to guide the thread and assist in retaining it until the time proper for
its release from the said take-up lug, and another cam-lug mounted on one of
said discs and adapted to exert a tension on the thread to tighten the stitch,
substantially as described.
3. A sewing-machine cake-up mechanism comprising a main driving shaft, a
take-up shaft parallel with said driving shaft and actuated therefrom vith a
variable movement, two parallel discs mounted on the forward end of the take-up

page_text: shaft and connected, at but a single point, by a pin that is adapted to also carry
the thread, a take-up and retaining device carried by said discs to positively control
the slack, and a cam-lug mounted ou one of said dises in position to exert a tension
on the thread during a portion of the rotation of the take-up, to tighten the stitch,
substantially as described.
4. In a sewing machine take-up mechanism, the combination, with the main
driving-shaft, the needle-bar and take-up, of a take-up shaft journalled in the
bracket-arm and extended longitudinally therein and parallel to the main driving-
shaft, the forward end of said take-up shaft being extended beyond the forward
end of said main driving-shaft, a curved pitman connecting the needle-bar aud
main driving-shaft and having its concave side or edge turned toward the adjacent
and forward extended portion of the take-up shaft, to pass the same, and connecting
mechanism between the rear end of the take-up shaft and the rear portion of the
main driving-shaft and through which the take-up is actuated with a variable
movement, substantially as described.
5. In a sewing machine take-up mechanism, the combination, with a main driving-
shaft, the needle-bar, mechanism to operate a looper, and a link for actuating said
mechanism from a crank on the rear portion of the main driving-shaft, of a rotary
take-up shaft mounted parallel with the main driving shaft and extended
longitudinally in the bracket-arm, a take-up on the forward end of said take-up
shaft, a slotted crank-arm on the rear end of the take-up shaft, and a pin carried
by the link that connects the main driving shaft and looper-operating mechanism,
said pin being engaged with the crank-arm on the rear of the take-up shaft, to
impart a positive variable motion to the take-up, substantially as described.
6. In a sewing machine take-up mechanism, the combination of a take-up shaft
mounted longitudinally in the bracket-arm and carrying a take-up on its forward
end, a cranked main driving shaft mounted in the bracket-arm and parallel with
the take-up shaft, a looper-shaft having a crank on its rear end, a link connecting
the cranks of the looper-shaft and main driving shaft and carrying a pin near its
upper end, and a crank-arm mounted on the rear end of the take-up shaft and
provided with a cam-slot engaged with said pin and through which is imparted a
variable motion to the take-up shaft, substantially as described.
Dated the 5th day of November 1895.
D. YOUNG & Co.,
11 & 12 Southampton Buildings, Loudon, W.C.,
Agents for the Applicant.