IMPROVEMENTS IN MACHINES FOR SEWING STRAW PLAIT to be as follows:er and
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
We OWEN ROBINSON and FREDERICK ROBINSON of the Champion Sowing
Machine Works, Victoria Street Kettering in the County of Northampton Sewing
Machine Manufacturers do hereby declare the nature of our invention for
"IMPROVEMENTS IN MACHINES FOR SEWING STRAW PLAIT to be as follows:-
"
First An improved Feeder and method of adjustment. We propose to make
our Feeder with a series of sharp points like needle points so as to more readily
penetrate Straw Braid or other material; and further, we propose to raise or
lower our Feeder by means of a piston & nut inserted in what is called the
Feeder Frame.
Second: An improved tension and method of adjustment This part of our
invention is applicable to a Machine Patented by William Walker of Dunstable
for Sewing Straw Hats, January 1883. We propose to fix on the back of the
looper cam an adjustable ring which carries a roller. This roller strikes against
a lever which is jointed to the Frame of the Machine the upper part of this lever
rests against a spring and tension discs or their equivalent. As the Machine
revolves, the roller on the ring comes in contact with the lever which gives a
pressure on the tension and maintains this pressure until the roller in its movement
leaves the lever. The object of the ring is to adjust the tension independently of
the needle cain.
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page_text: We OWEN ROBINSON and FREDERICK ROBINSON of the Champion Sewing
Machine Works, Victoria Street, Kettering, in the County of Northampton, Sewing
Machine Manufacturers do hereby declare the nature of our invention for
IMPROVEMENTS IN MACHINES FOR SEWING STRAW PLAIT, and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement :-
Our invention relates to improvements on straw plait sewing machines, the
object being to increase the efficiency of the machine by ensuring a firmer hold
of the work by the feeding instrument, and of controlling, with a greater nicety
than heretofore, the supply of the thread.
We will describe our improvements as applied to a machine patented by
M William Walker on the 10th January 1883, as they were mainly designed for
the perfecting of that machine.
In Sheet 1 of the accompanying drawings, Fig: 1 is a side elevation of a Walker
straw plait sewing machine, with our improvements applied thereto; and
Fig 2 is a front view of the same.
The Figures in Sheet II represent certain parts of the mechanism detached,
and also illustrate the movements of the sewing instruments and their action
relatively to each other.
In Figs 1 and 2, A is the bed plate and A' the bracket arm of the machine,
cast in one piece, and A' is a standard, also cast with the bed plate, and carrying
the work table B.-C is a horizontal cam shaft having its bearings in the standard
and bracket arm, and furnished with a band pulley for driving it.-D is the needle
bar fitted with a peculiarly shaped needle d, and E is the presser bar mounted in
the bracket arm as as usual. The needle bar receives its vertical movement from
a rock shaft D¹ carried in bearings which project from the bracket arm A¹. The
rock shaft is fitted, at its opposite ends with arms, that nearest the needle bar
being connected by a short link to a pin projecting from the needle bar, while the
arm at the other end of the rock shaft connects by a link D² with a pin that
carries a bowle d' working in a cam groove D³ cut in the inner face of the band
pulley. A radius arm D', pivotted to the bracket arm A', serves to support the
pin which carries the bowle while yielding to its motion in the cam groove.
The needle d, shewn detached and on an enlarged scale at Figs. 1*, is rehated in
front immediately above its point, so as to form on its front an upper and a lower
look or barb, which face each other. These hooks serve to retain the loop brought
up through the work by the needle, the one as the needle is ascending out of the
work, and the other as the needle is descending through the work. This needle
takes the thread, as usual, froin a whirl when it has descended through the work,
draws the thread which it has received up through the work, formning it into a
loop, and to prevent the loop escaping from the needle during its descent, an
instrument termed a loop retainer is provided. This instrument is shown in
Figs. 1 and 2 as consisting of a horizontal steel wire carried by an arm F keyed
to a rock shaft F, which is carried in bearings in the bracket arm A¹ and
standard A. The rock shaft, besides its axial motion which it obtains from a
cain F on the cam shaft C, acting on an arm of the rock shaft, receives an endway
motion from a grooved cam F³ on the cam shaft acting upon a bowle fitted to the
rock shaft. By this means the loop retainer is carried forward in front of the
needle, and then rocked into contact with the loop in order that it may put a

page_text: tension on the loop thread. The loop, while thus held, will permit of the needle,
in its descent, securing the loop in its upper hook preparatory to its drawing down
the loop into and through the work. So soon as the upper hook has secured the
loop by carrying it through the work, the loop retainer is moved back to its
quiescent position ready to repeat the action described.-G is the whirl, which
lays the thread in the hook of the needle, and is operated, as usual, by means of a
pinion G¹ keyed to its stem, and geared into by a rack G-The rear end of this
rack is pivotted to a radius arm C³, which has its fulcrum on the bed plate.
A bowle carried by this ann takes into a grooved cain G' on the cam shaft C.
The whirl is mounted in a vertically socketted bracket G³ bolted to the bed
plate A. The thread is taken from a bobbin not shown in the drawing, and
threaded through a guide g affixed to the standard A², thence it passes to the
whirl.
The needle, when it has brought down the loop of thread through the work,
requires to be released from the loop preparatory to its next ascent. This is
effected by means of a loop opener mounted on a horizontal spindle H, which
turns in bearings carried by the standard A2; it is fitted with a pinion h¹.
Gearing into this pinion is a segment rack forming one end of a rock lever H¹
which has its fulcrum on the standard A. A bowle carried by this rock lever
enters the groove of a face cam H2 on the cam shaft, the rotation of which rocks
the lever, and through the rack and pinion a reciprocating axial motion is imparted
to the loop opener. This loop opener may be described as a curved finger broad at
its root and tapering to a point. When the needle has arrived at the position for
delivering its loop, the point of the loop opener will advance into the loop, and as
it turns, it will present a broader surface to the loop which it has entered. Thus
the loop will be gradually expanded and will be disengaged from the needle, which
will then be free to rise and take up a position for re-entering the work. In order
To ensure the proper relative action of these two instruments, the needle is
chamfered on its side above the upper hook, to reduce the thickness of the stem
to less than the breadth of the hook, and thus to provide a space for the entrance
of the point of the finger into the loop. Similarly, to prevent the loop opener h,
by its lateral pressure on the needle, thrusting the needle out of line, the loop
opener is furnished with a vertical flange, which enables it to embrace the needle,
and prevents the needle from unduly swerving laterally.
I is the feeder frame which carries the dog for feeding the work forward. This
feeding frame rocks on a fulcrum carried by a vertical projection cast on the bed
plate A. This frame I is slotted to receive its fulcrum pin and allow of its rising
vertically as well as rocking under the combined action of the two cams I¹ I on
the cain shaft C. The feeder frame is raised to project the feeding dog through
the slot of the work table B and bring it into contact with the work by means of
the cam 1, which underlies and bears upon the shoulder of the frame, and the
forward motion of the frame to give the feed is obtained from the cam 12, which
is double acting, and gives alternately a long and a short motion to the feed dog.
The frame is furnished with a bowle which is held up to the cam 1' by a coiled
spring 1, which spring serves to impart the back motion to the feeder frame when
the pressure of the cam upon the bowle is released.
Thus far we have described the construction and working of the Walker plait
sewing machine, and we will now proceed to explain the nature of our improvements
as applied thereto.
In order to ensure the proper feeding of the work, we have found it necessary
to make the feed dog take hold of the double thickness of plait, that is being
sewn, and for this purpose we form the dog as shown in plan and side view at
Figs: 3 Sheet II. The face of the feed dog i, it will be seen, is fitted with a series
of needle points in lieu of the serrated surface of the ordinary feed dog. These
points we make of such a length as will enable them to penetrate the overlying
or second thickness of plait, and by obtaining such a hold of the work, we are
enabled readily to manipulate it, elongating or contracting the elastic pluit as is

page_text: required to suit the varying shape of the work. We also provide for the vertical
adjustment of the feed dog i on its rocking frame I, to ensure the proper penetration
of the points into the work. The dog i is formed with a stem i, which fits at one
part a vertical socket made to receive it in the feeder frame, which frame is shown
detached in side and face views at Figs: 4. Through the bottom of this socket the
stem projects, and it is threaded to receive an adjusting nut . Surrounding
the stem, and enclosed in the socket, is a coiled spring ³, which gives the feed dog
a tendency to rise and effect a greater penetration of the work. This tendency is
however checked by the nut, the turning of which will adjust the vertical
position of the dog on the frame I with great ease and accuracy.
In order to bring under more perfect control the supply of the thread to the
needle, we provide an arrangement of mechanism which will stop the supply at the
moment that the needle is rising to tighten the last formed stitch, and thereby
compel the needle to take up the slack thread. When this is done, the mechanism
will release the supply thread and enable a take up lever, assisted by the whirl, to
draw off from the bobbin the length of thread required for forming the next stitch.
We have said that the thread is taken from a bobbin not shewn in the drawing,
led through a guide g affixed to the standard A2, and passed thence to the whirl G.
In passing to the whirl, we now lead it between a pair of friction discs G
threaded upon a horizontal rod G7 projecting from the standard A', and from these
discs it is led through an elastic take up lever Gs to a fixed guide g₁ carried by tho
standard A2 and thence to the whirl Ĝ. A slight coiled spring on the rod G'
serves to keep the discs together, and is a medium for imparting a brake pressure
to the discs when it is required to hold the thread against the pull of the needle,
and insure the tightening of the last formed stitch. The brake pressure is obtained
from a break lever CP, which has its fulcrum on the standard A². The upper end
of this brake lever is slotted to allow the rod G7 to pass through it, and its lower
and is curved to enable it to tie in the path of a bowle, which is carried by the
loop opener cam H on the cam shaft C, see the detached views Figs: 5, which
represent the face cam H in front, back, and edge views, and the bowle as mounted
on a ring fitted to, and adjustable axially on the back of the cam.
As this bowle, by the rotation of the cain H, is caused to bear upon the tail of
the brake lever, the upper end of that lever will, through the coiled spring on the
rod G7, put an elastic pressure upon the near friction disc and cause the thread to
be gripped between the discs, and the supply to be stopped until the bowle has
cleared the tail of the brake lever. The effect of this will be to compel the needle,
in its ascent, to draw up the slack thread, and thereby tighten the last formed
stitch. In the ring Go carrying the bowle, a segment slot is formed to receive a
clamping screw, which is passed through the can, and when tightened up by a nut
on the screw the ring will be held fast in any desired position on the cam. This
axial adjustment of the ring G1° provides for the proper timing of the action of the
bowle upon the brake lever, the timing requiring adjustment according to the class
of work in hand.
So soon as the tightening of the stitch is effected, the brake lever will cease to
press, and the clastic take up lever being free to act, will draw off a fresh supply
of thread from the bobbin. At this time the whirl remains at what may be terined
its forward position, that is to say, the position which it assumed on laying the
thread in the hook of the ascending needle. While doing this, it lapped around its
periphery a certain length of thread which was required for the formation of the
long stitch. To understand this action of the whirl, it will be necessary to refer
more in detail to its construction. The upper part of the whirl is cylindrical.
Standing up from its top end, and close to the side thereof, is a tubular projection 1,
which is slit vertically through its whole length.-This slit is continued down into
the body of the cylinder, that it may communicate with a transverse inclined saw
cut formed in the cylinder, and extending upwards from the periphery to the top
end of the cylinder. This contrivance is for the purpose of facilitating the
threading of the whirl, the thread having only to be caught into the saw cut and

page_text: pulled to tension, in order to effect its insertion in the tubular projection. Standing
up from the top end of the whirl is a flange 2, which serves to present a shoulder
to the thread when inserted into the whirl, and also provides a circular face to
receive a lap of thread which is destined to provide for the formation of the long
stitch. The hook needle, it will be understood, works in the line of the axis of
the whirl, and when brought down to its lowest position, the whirl is moved
axially, and caused to lay the thread in the needle. At the same time the shoulder
of the flange 2 will catch the thread which lies straight across the whirl from the
tube 1 to the shoulder 2, and the thread will then be laid over the circular face of
the flange, a proportionate length being drawn from the bobbin to supply the
surface of the whirl.
In order that the operation of sewing by the improved machinery inay be clearly
traced, we have added to the Figures already described three diagrams illustrating
the movements of the sewing instruments in connection with the device for
controlling the supply of thread. By referring to Figs. 1 and 2, it will be seen
that the feed has just taken place, and that the feed dog i has dropped to its
normal position preparatory to the return of the feeder frame I froin its most
advanced to its back position; thus the feed for the long stitch has just been
effected.
It will also be seen that the needle & has passed through the work, delivered its
loop to the loop opener h, and is about to receive its thread from the whirl C,
which it draws through the loop held by the loop openor h. At this time the
brake lever Go is out of action, and the thread is free to pass between the discs Ge
at the pull of the whirl G, which draws the thread through the elastic take up
lever G ready for the formation of a second long stitch.
In the diagram, Fig: 6, the needle is shewn as having drawn a fresh loop
through the work, and as in the act of tightening the last formed stitch.―The
brake lever G is now in action, and the feed of the thread is consequently arrested.
Thus the needle d, in rising, will pull against the slack thread below the work, that
is, the loop just released from the loop opener h, and the thread held by the
take up lever G³. The feed dog i is represented as in its back and depressed
position.
In the diagram Fig: 7, the needle d is shown as having reached its highest
position and tightened the stitch; the feed dog i has been raised and is ready to
innke the short feed, the brake lever G is out of action, and the take up lever G*
has returned to its extreme position. The loop opener is in its back position, but
ready to advance, and the loop rotainer has now come forward and commenced to
put a tension on the loop in the needle d.
In the diagram Fig. 8, the needle d, having carried down the loop of Fig: 7 into
the work, and delivered it to the loop opener h, is rising without a thread in order
that the long feed may take place, while the loop that is to form the long stitch is
held by the loop opener h. To permit of the feed for this stitch taking place, the
whirl G returns to its back position, and in doing so, it gives off the thread, which
is laid upon the flange 2. This back movement of the whirl G is synchronous with
the advance of the feed dog i, the loop opener & meanwhile retaining its hold on its
loop, as shown in Fig: S. This retention of the loop is for the purpose of
presenting the open loop to the descending needle d, which at its next ascent
draws a fresh loop through this open loop, when a repetition of the operations
above described will commence. The straw plait to be sewn is passed through a
guide which acts as a gauge for ensuring the proper overlapping of the plait, and
the machine being set in action, the attendent has only to turn the work as it is
sewn, and adjust the overlapping plait as above indicated, to suit the requirements
of the article that is being formed.
It will be understood that this mechanism, although described in connection with
the sewing of straw plait, is equally applicable to chip plait and braid or other liko

page_text: Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed, we declare that what
we claim is
1. The application to straw plait sewing machines of brake apparatus as above
described for stopping the supply of thread while the needle is tightening the last
made stitch.
2. The construction of feed dog as above described, and the mode of fitting it to
the feeder frame or carrier, and adjusting its height relatively thereto.
L
1- 100 A
NEWTON & SON,
Agents for the Applicant.