IMPROVEMENTS IN LOCK-STITCH SEWING MACHINES
Year: 1884

page_text: 12
I, DANIEL JONES, of 27, Great Frederick Street, Cardiff, in the County,
of Glamorgan, Builder, do hereby declare the nature of said invention for
"IMPROVEMENTS IN LOCK-STITCH SEWING MACHINES," to be, as follows:―
This invention, which relates to lock-stitch sewing machines of the kind described'
in the Provisional Specification left with a former Application for Letters Patent
made by me dated the sixth day of October, 1884, and numbered 13,233, that is to
say, wherein a reel is employed as well for the under thread as for the upper thread,'
consists in so arranging and operating parts of the mechanism that an improved
lock-stich is obtained.
As each loop of the upper thread is formed by the motion of the needle a slide,
over the end of which is passed the under thread, is moved forward to pass a loop
of the under thread through the loop of the upper thread. A hook formed on the
carrier enclosing the reel of the under thread engages in turn with each loop of the
under thread and carries it round as it rotates. The lower thread is consequently
passed through its own loop and a knot or locked-stitch is formed which, while of
an easy running nature, prevents both the upper and under threads from being
drawn out of the material being sewn. Friction of the upper thread is reduced.
The carrier of the under reel may be furnished with two hooks, and instead of
rotating in one direction only, it may be made to partially rotate alternately in
contrary directions, each hook egaging in turn with a loop in the under thread.
The slide aforesaid is operated from the driving shaft of the machine.

page_text: Improvements in Lock-stitch Sewing Machines.
I, DANIEL JONES of 27, Great Frederick Street, Cardiff, in the County of
Glamorgan, Builder, do hereby declare the nature of my said invention for
"IMPROVEMENTS IN LOCK-STITCH SEWING MACHINES," and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement :-
This invention which relates to lock stitch Sewing machines of the kind
described in the Provisional Specification left with a former application for Letters
Patent made by me, dated the sixth day of October 1884 and numbered 13233, that
is to say, wherein an ordinary reel is employed as well for the under or second,
thread as for the first or upper thread, consists in so arranging and operating parts of
the mechanism that an improved lock-stitch is obtained."
As each loop of the upper thread is produced by the motion of the needle; a slide,
over the end of which is passed the second or under thread, is moved so as to cause
a loop of the under thread to be passed through a loop of the upper thread. A hook
formed on the carrier enclosing the reel of the under thread engages in turn with
each loop of the under thread which is passed over the carrier as the latter rotates.
Instead of a slide for passing the under thread through the loops of the upper
thread, a pivotted arm is preferably employed, and is actuated by a slide. The
lower thread is consequently passed through its own loops, and knotted or locked
stitches of special character are formed, which, while of easy running nature, yet
prevent the withdrawal of both the under and upper thread from the material
being sewn.
Friction on the upper thread is reduced.
The reel carrier may be furnished with two hooks, and instead of continuously
rotating in one direction only, it may be adapted to oscillate or partially rotate
alternately in contrary directions.
Under this modification one of the hooks is employed to engage with the loops,
the other acts as a "take-up" furnishing the requisite supply of thread, and no
more, for each stitch in turn.
Referring to the accompanying sheet of drawings, Fig. 1, represents a part
vertical section and part side elevation of a portion of a sewing machine constructed
in accordance with my said invention. Fig. 2. is a part plan. Fig. 3. is an end
view of the carrier a which has one hook only formed thereon. Below the barrel m
which contains the reel 6 of the under thread is pivotted the arm n¹ capable of
being moved on its pivot by the slide k carried below the bed plate h and connected
to the lever hinged to the bearing 12 and impinged upon by the cam 7 carried on
the driving shaft e. The spring 13 secured at one end to the bed plate h and at
the other to the lever 1, tends to maintain the slide k at the outward end of its
range of travel. The arm n¹ engages at. the top with a recess in the slide k, as
shown. Over the nose n² of the arm n¹ is passed the under thread, and as each
loop of the upper thread is formed at the needle N the arm n¹ is tilted by the
action of the cam and so the under thread is thrust inward and a loop thereof
'1

page_text: passed through each loop of the upper thread. As each loop of the under thread
is passed in this manner through a loop of the upper thread, the hook of the carrier
engages with each loop in turn of the under thread, the loops of which are conse-
quently widened as the carrier a rotates. The under thread is embraced by each
of its own loops, and each loop is drawn up in the material being sewn by the
engagement of the hook of the carrier with the loop next formed. The threads
become thus interlocked as diagramatically shown at Fig. 4 in which c¹ represents
the upper thread and c the under thread. The knot produced is of an easy running
nature and is such that when tightened to form a stitch neither the upper nor the
under thread can be withdrawn from the material sewn.
The carrier a is rotated through the medium of the forked lever d pivotted at d¹
to the driving shaft e. The front ends of the lever d are raised from contact with
the carrier to allow the thread to pass by the action of the cam g.
At Figs. 5 and 6 is illustrated an arrangement in which knotting mechanism is
applied to a reel carrier a which oscillates or has motion in a rotary sense alternately
in opposite directions. Oscillation of the carrier may be caused by the use of an
eccentric acting from the driving shaft, or it may be caused by other suitable means.
The under thread c, after coming from the reel b, is passed through a suitable
tension p conveniently carried on the nose m¹ of the barrel m. Thence it is taken
round the anti-friction roller a secured within the hook A which serves as a
"take-up" and furnishes the supply of thread from the reel b requisite for the
passage of the carrier a through the loops. From the hook A the thread c is con-
ducted back to the needle through a hole in the nose m¹ and through a slot in the
slide k near the needle, as shown.
In the travel of the carrier a towards the left hand-see Fig. 5-the hook A¹,
furnished with an interior anti-friction roller xl, enters a loop formed, as ordinarily
in the upper thread c¹ at the needle.
The slide is, by means of a crank or other suitable device, drawn back so as to
cause the lower thread c to engage with the hook A¹. The carrier then travels
back towards the right hand, taking with it the loop of the under thread engaged, as
aforesaid, by the hook A. As the carrier continues to travel to the right the hook A*
enters the loop of the under thread and opens it for the passage of the carrier.
When the carrier reaches the limit of its range of travel in that direction the said
loop slips off the hook A¹ Meantime the hook A, in travelling up to near the
nose mi, has given the supply of thread required to permit the passage of the
carrier a through the loop which has, as aforesaid, been so far taken round
the carrier by the hook A¹. The carrier now returns towards the left hand, and
the hook A, acting as a "take-up," draws up the loop through which the carrier
has passed and tightens the knotted stitch in the material being sewn.
The driving mechanism is so arranged that the needle descends and rises once
whilst the carrier travels from one limit of oscillation to the other and back.
Instead of being arranged to have motion about a horizontal axis, the carrier a
may be adapted to have motion about a vertical axis, or an axis inclined at any
angle to the plane of travel of the needle.
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
1st In a lock-stitch sewing machine, the use in conjunction with the needle
whereby loops are formed in the upper thread of a device whereby a loop of the
second or under thread is caused to pass through each loop of the upper thread and
a hook whereby the said loop of the second or under thread is afterwards caused to
pass over or around a carrier or container that contains the reel from which the
under thread is being drawn, substantially as described.
2nd In a lock stitch sewing machine, the combination with a reel carrier and its
spindle for containing the reel upon which the second or under thread is wound of

page_text: a pivotted arm or equivalent device for passing a loop of the second or under thread
through cach loop of the upper thread whereby a special knotted character is
imparted to the stitches, substantially as described and shown at Figs. 1 to 4 of the
accompanying sheet of drawings and also as described and shewn at Figs. 5 and 6
of the said. drawings.