Improvements in Sewing Machines.
Year: 1892

page_text: Date of Application, 22nd Jan., 1892
Complete Specification Left, 24th Oct., 1892-Accepted, 26th Nov., 1892
PROVISIONAL SPECIFICATION.
Improvements in Sewing Machines.
I, JOHN POYSER, of Sherwood Rise, Mansfield, in the County of Notts.,
Gentleman, do hereby declare the nature of this invention to be as follows:-
The object of my invention is the construction of a sewing machine, which will
produce, at pleasure, either a lock-stitch or a chain-stitch.
The invention is carried out in practice, by combining, with a rotary lock-stitch
machine, suitable devices, which enable it, when so desired, to form a chain-stitch.
As an instance of the use of the invention, I will describe its application to a
lock-stitch machine, having a rotary hook, a circular spool for the under thread,
and a brush for holding the loop, constructed on the well-known Wheeler and
Wilson principle.
The machine may be formed substantially in the usual way, with the exception
that the brush instead of being permanently fixed, in contact with the lower part of
the edge of the rotating hook, is placed in a slot or otherwise so arranged, that it
can be moved to the upper part of the edge of the hook, when it is required to.
make a chain-stitch.
To cause the machine to produce a chain-stitch, the brush is moved to the upper
position, as above described, the spool for the under thread is then removed, and a.
plain disc, of the same shape as the said spool, is inserted in its place. This disc
has affixed to its back, a suitably formed projecting piece, which lies in the cavity
provided behind the point of the hook. The effect of this arrangement is, that the
loop, when formed and thrown off, is held by the brush in a more nearly horizontal
position than when making a lockstitch, while the projecting piece aforesaid, holds
the loop open and keeps the back part of the loop behind the hook, so that the
needle in its descent enters the loop, the hook then advances and takes the fresh
loop from the needle while the previous loop is thrown off and tightened around the
new one, as the hook rotates, thus forming an ordinary chain-stitch.
It will be seen that this arrangement involves but slight alteration in existing
mechanism, while the advantages of a machine which will make either lock or
chain-stitch at pleasure are obvious.
Dated this 22nd day of January 1892.
AMBROSE MYALL,
21, Cockspur Street, London, S. W., Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Sewing Machines.
1, JOHN POYSER, of Sherwood Rise, Mansfield, in the County of Nottingham,
Gentleman, 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:-
The object of my invention is to effect improvements in the construction of that
class of sewing machines, which will produce at pleasure, either a lock-stitch or a
chain-stitch.
The invention is carried out in practice by combining with a rotary lockstitch
machine, suitable devices, which enable it, when so desired, to produce a chain-
stitch.
As an instance of the use of the invention, I will describe its application to a

page_text: lock-stitch machine having a rotary hook or looper, a circular spool for the under
thread, and a brush for holding the loop, constructed on the well known "Wheeler
and Wilson" principle.
In the accompanying sheet of drawings, which illustrates the above application
of the invention, only such parts of the machine are shewn, as are necessary to
explain the construction and operation of my improvements.
Fig. 1 is a front elevation of a "Wheeler & Wilson" rotating lockstitch hook
or looper, with its brush, the spool and spool guard not being shewn.
Fig. 2 is a front elevation,
Fig. 3 is a back elevation, and
Fig. 4 a plan of the improved device, used in conjunction with the hook, for
forming a chain-stitch.
Fig. 5 is a front elevation, and
Fig. 6 is a back elevation, shewing the hook with the said improved device in
position therein.
Similar letters of reference denote similar parts throughout the drawings.
A is the rotary hook or looper, and B the brush, adapted for forming a lockstitch
when used with a circular under-thread spool, in the usual way, C is the needle
and D represents the table of the machine. To form a chain-stitch the said circular
spool is removed from the looper and the device shewn in Figs. 2 to 6 is inserted in
its place. The said device consists of a disc E, having the same general outside
dimensions as the circular spool aforesaid. It has a plain convex surface in front,
but the greater part of the back is recessed, or cut away as shewn at F, leaving a
narrow rim or margin H. A portion of this is cut down as shewn at J, while a
small projection K is furnished thereon.
Affixed by one end, within the recess F, is a curved flat strip or piece L, the
form of which is best shewn in Figs. 2, 3, & 4. The said piece is of hooked shaped
form, and the projecting part L' fits within the space A¹ behind the hook A² of the
looper A.
The device is retained within the looper by the usual spool guard, in the same
manner as the ordinary spool, the guard being omitted in the drawing for the sake
of clearness.
The direction of rotation of the looper is indicated by the arrow.
After the hook A has taken a loop from the needle C, the said loop passes round
the disc E, and when thrown off by the edge of the looper is held temporarily by
the brush B. When the needle again descends, the piece L comes within the loop,
in such manner that it holds the backthread of the loop away, so that the needle
descends between the two sides of the loop, and after the hook A² has taken the
next loop from the needle, the previous loop is pulled away from the brush and is
tightened around the new loop by the rotation of the looper.
The thread is shewn in Figs. 5 & 6, the position of the parts chosen being at
the moment when the hook A' is taking a new loop M from the needle, the
previous loop still held by the brush, being marked N.
The projection K on the disc E lies in the space between the parts A³ and A'
of the looper, and thus serves to keep the said disc in its proper position relatively
to the looper, while the rim H is cut away at J for the purpose of reducing friction
and further for allowing the thread and back part of the loop to pass freely round
the disc to the back of the piece or strip L.
A rounded projection L is formed on the piece L, as shewn most clearly in
Fig. 3, to enable the thread to slip more easily and to prevent any sagging at the
back of the loop, and the looper is recessed out at A', Fig. 1, to facilitate the
thread passing behind the piece L.
I do not confine myself to the exact construction of the piece L shewn in the
drawings, as such piece can for example be formed of wire bent into the required
form.
In my Provisional Specification, I state that the brush must be raised to a higher
position when the machine is required to produce a chain-stitch, but I now find this

page_text: to be unnecessary and that no provision for raising or lowering the brush is
required, the position for the lock-stitch answering equally well for the chain-
stitch.
By means of my improved device an ordinary chain-stitch is satisfactorily
produced on a lock-stitch machine of the class described, no alterations are made in
the mechanism of the machine, while the change from lock to chain-stitch or
vice-versa can be performed in a moment.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. In a rotary lock-stitch machine, a device consisting of a blank disc having
attached to the back a curved strip, the said device fitting within the rotary hook,
to replace the lock-stitch spool and enable the machine to produce a chain-stitch,
substantially as described.
2. In a rotary lock-stitch machine, a device consisting of a disc E, having a
convex front surface, a recess Fat back, a rim H, cut down at J, a projection K
and a curved strip L, the said device fitting within the rotary hook, to replace the
lock-stitch spool and enable the machine to produce a chain-stitch, substantially as
described.
3. In a rotary lock-stitch machine, the combination of a rotary lock-stitch
hook A, a brush B, and a device consisting of a disc E, having a convex front
surface, a recess Fat back, a rim H cut down at J, a projection K and a curved
strip L, enabling the machine to produce a chain-stitch, substantially as described.
AMBROSE MYALL,
21, Cockspur Street, London, S.W., Agent for the Applicant.