A Double Hemstitch Machine.
Year: 1896

page_text: Date of Application, 15th Apr., 1896
Complete Specification Left, 7th Nov., 1896-Accepted, 16th Jan., 1897
PROVISIONAL SPECIFICATION.
A Double Hemstitch Machine.
JOSEPH WALKER, 32, Beechfield Street, Mountpottinger, Belfast Mechanic
do hereby declare the nature of this invention to be as follows:-
This invention relates or applies to the stitching of two distinct rows of
hemstitching or French veining simultaneously; the invention is applied to a
sewing machine with two rotating hooks or oscillating shuttles; the machine is
constructed with suitable cams on the arm and operates unto two levers or
connecting rods, and these are connected to a double quadrant which transmits its
movements to two distinct needle clamps made fast to one needle bar, both clamps
getting a vibrating movement simultaneously in opposite directions;-between the
needles there is a spreader made fast to the same end of needle bar as the clamps,
the spreader is prepared with two small grooves to receive the needles in their
descending movement when machine needles are in the inside stitch.
Dated this 13th day of April 1896
JOSEPH WALKER.
I, JOSEPH WALKER, of 32 Beechfield Street, Mountpottinger Belfast, Mechanic,
do bereby 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:-
My invention relates to a novel construction of sewing machine for producing
two distinct rows of hemstitching simultaneously in fabrics.
The invention is specially applicable to machines of the Wheeler & Wilson
type with two rotating hooks although it can be adapted to other forms of
machine.
The features of novelty constituting the invention are pointed out in the claims.
And in order that my said invention may be properly understood I have hereunto
appended three explanatory sheets of drawings, whereon,
Fig. 1 is a side view of a Wheeler & Wilson machine fitted with my
improvements.
Fig. 1 is a side view of the needles and accessory parts Fig. 1.
Fig. 2 is a plan view of the machine.
Fig. 3 is an inverted plan of the machine.
Fig. 4 is an enlarged view of the needles and accessory parts.
Fig. 5 is a detail view of the gearing and cam.
Fig. 6 is a front view and Fig. 6A a side view to an enlarged scale of the spreader
or spear.
Fig. 7 is an enlarged diagram of the double hem-stitch produced by the
machine.
Figs. 8 and 9 are detail views.

page_text: Referring to the drawings whereon the same reference letters wherever repeated
indicate the same or similar parts.
In carrying out my invention I fit on the usual horizontal driving shaft a of the
machine, a bevel wheel 6 (see also Fig. 5) which gears with a bevel wheel c carried
on a stud c¹ secured to the cover plated which latter is held in place by screws e.
Secured to the bevel wheel c and revolving with it on the stud c is a spur pinion f
which gears with the spur teeth of the cam wheel g revolving on the stud g'. In
Fig. 1 the pitch lines of the gear wheels are indicated.
Cast in one with or secured to the wheel g is a cam which is of a peculiar shape
as shown at Fig. 5. It is made with two corresponding narrow projections ¹ and
two corresponding broad projections h² also with two corresponding slight pro-
tuberances h³. The projections h' and 2 although not of the same breadth are of
the same length. The action of the cam will be hereinafter described.
A double quadrant" i, turning on a pivot ", has a pin j at its lower end which
is actuated by the cam h. The piu ; has a friction roller on it. The quadrant i is
grooved at and in this groove are two slides j, j³, having pins projecting from
them to which are secured the end pieces 2, 3, of two connecting rods k, k¹. The
slidės,, can be clamped in any desired position in the quadrant groove by means
of the butterfly nuts 1, 1. The connecting rods k, k', pass through guide openings
made in a guide bracket m secured to the arm A of the machine. As will be seen
the rods k, k', are jointed to their end pieces, k³, by adjustable couplings
consisting of two screws which are passed through a washer k then through a
slot in the end pieces and are entered in holes in the ends of the rods. On
slackening the screws the length of the rods can be adjusted lengthwise and when
adjusted the parts can be securely clamped together again by tightening up the
screw k¹.
y is a spring which is secured to the lower end of the quadrant at its one end and
to the plate d at its other end.
Each connecting rod is enlarged at k and carries in this enlargement a roller k³
having a hole bored vertically through it. Passed through the hole in the roller
of the connecting rod k is a vibrating bar p whose lower end is screwed to a
clamp pl secured by a pivot pin p² to a cross piece q' (see also Figs. 14 and 4)
attached to the lower end of the needle bar g. In the same manner there is passed
through the roller of the connecting rod k a vibrating bar r whose lower end is
screwed to a clamp secured by a pivot pin 2 to the cross piece q'. The clamps
are capable of lateral adjustment in slots s, indicated in dotted lines at Fig. 4,
through which their pivot pins pass. The pivot pins are clamped in the adjusted
position in the slots by means of nuts s' (Fig. 1A) at the back.
Fitted in the centre of the cross piece q' is a spear or spreader t which has a
spear point t¹ as shown at Figs. 6 and 64 and also a longitudinal slot in it (or
two grooves one at each side) for the reception of the needles when they are
brought together.
u, u', are two needles which are secured respectively in the clamps r¹, pl. u² are
pinching screws for clamping the needles in position when adjusted. varé bent
wire guides for the threads before passing to the needles.
w are the spools and w', w, the two threads.
is a guide through which the threads pass before going to the guidės v. This
guide a consists of a plate with two thread holes in it and which is secured to the
arm A by a wire a¹.
B is the presser foot.
The dotted liues at C represent two Wheeler & Wilson rotary hooks or other
suitable form of rotary hooks or shuttles.
In the diagram Fig. 7, which shows the kind of stitch produced in the fabric, z is
the under or shuttle thread and 21 the upper or needle thread. The left hand
view (Fig. 7) shows the under side of the cloth and the right hand view the upper
side. It is to be understood that these views do not show the material absolutely

page_text: correct as the open spaces are made by pushing.aside the cross fibres, as usual,
instead of by cutting some of them away as is shown in the views.
The action of the machine is as follows:-
Presuming that the connecting rods k, k¹, and the clamps r, p', have been
properly adjusted in position and the needles threaded, the driving wheel is rotated
in the direction of the arrow whereupon the shaft a, through the bevel and spur
gearing, revolves the wheel g in the direction of the arrow (Fig. 5) and causes the
cam to impart a vibrating motion to the quadrant i which in its turn, through the
connecting rods k, k, causes the bars r, p, to réciprocate, at the same time, towards
each other and away from one another alternately. The oscillatory movement of
the bars r, p, causes the clamps r, pl, to oscillate on their pivots and thereby
alternately move the needles u, u', close to the spear t (as at Fig. 1) and away
from it, (as shown in full lines at Fig. 4). The dotted and full lines Fig. 4 show
the extent of this lateral swinging movement of the needles u, u'.
It will be seen that the speart is longer than the needles and each time the
needle bar descends it penetrates the cloth, and, according to the width of the
spear head t', pushes aside to a greater or less extent the threads so as to form
the usual opening or space produced when doing "open work" stitching.
Now, on referring to the diagram Fig. 7, the first stitch 1, 1, of the needles is
made when the needle bar g is at its first down stroke and the pin; of the quadrant i
is travelling along one of the faces 1 of the cam 7 (see Fig. 5) the needles as a
consequence being "open" or away from the spear as shown in full lines at Fig. 4,
by the time the needle bar commences its next down stroke the pinj has reached
the point of the cam and the needles as a consequence are "closed," as shown
in full lines at Fig. 1 and in dotted lines at Fig. 4, so that the spear with its
needles close beside it penetrates the cloth at a (the cloth having in the meantime
been fed forward by the feed mechanism this distauce) and makes the open space;
at the commencement of the succeeding ascent of the needle bar the needles are
opened under the action of the part 2 of the cam h to an extent sufficient to widen
out the opening in the cloth and also at the same time to permit the hooks C to
lock the stitches 2, 2; during the continued ascent of the needles, after having
cleared the cloth, and also during their subsequent descent, the cloth is fed, by
the feed mechanism of the machine, backwards to such an extent that the next
entry of the spear and needles is made at O the pinj travelling over the point /*
and the needles being "closed"; at the next succeeding ascent of the needles
they are opened out, under the action of the part 3 of the cam to an extent
sufficient to widen out the opening O and also to permit the hooks to lock the
stitches 3, 3; the feed mechanism now feeds the cloth forward so that the next
stitch takes place at 4, 4, the pin j, travelling over the point and moving along
the next face 1 in order to recommence a new series of stitches.
The feed and shuttle mechanism can be the same as that used on the ordinary
Wheeler and Wilson machine. The feed méchanism is however adapted to give
the proper forward and backward feed movement to the feed plate by means of
cams D, D', as shown at Figs. 8 and 9. D is the feed cam and D' the cam for
raising and lowering the feed plate at the proper times. The feed and shuttle
mechanism is shown at Fig. 3, D' being the feed shaft, D' the feed quadrant,
D the rod for actuating the shaft D' from the quadrant, D' the quadrant spindle,
Do the crank on the spindle and D' the cam pin, on the crank, which works in the
groove Do of the feed cam D. E is the main driving shaft for rotating the shuttles
and which also drives, by the pinion E', the cam wheel D. Fitted on the opposite
eud of the spindle D8 of the cam wheel D is the_cam D₁ upon the periphery of
which runs the roller D secured to the crank D' of the rock shaft De, which
latter is connected by the bar D" to the feed shaft D. D" is the feed plate.
If desired a positive cam can be used instead of the cam h working in conjunction
with the spring y.
This machine has the following advantages, amongst others, over other machines
of the same class, aiz., that the double hem-stitch can be performed by the two

page_text: needles simultaneously and at one operation; that only one needle bar is used;
that only one spear is employed; that it is not necessary to give the rotary shuttles
a backward and forward movement; that it is not necessary, as in some machines,
to pass the cloth twice through the machine in order to produce the double line of
stitching; that the stitching can be carried continuously round small curves or
corners; and that the length of the stitches can be easily adjusted.
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
-consider novel and desire to claim is :-
1. A machine for sewing two distinct rows of hemstitching simultaneously in
fabrics, constructed, arranged, and operating substantially as herein before described
with reference to the drawings annexed.
2. In a double hemstitch sewing machine the combination with the needle
bar, of a "spear" or "spreader" fitted thereto, of two needles fitted one at each
side of the spear or spreader, and of means for imparting at the proper times
a lateral "opening" and "closing" movement to the needles, substantially as
herein before set forth.
3. In a double hemstitch sewing machine, the combination of the needle bar g,
the spear or spreader t, the vibrating clamps r, p', the needles u, u', fitted in the
clamps, and cam mechanism or its equivalent for causing the needles to simul-
taneously move near to and away from the spear or spreader substantially as
hereinbefore described with reference to the drawings annexed.
4. In combination, the needles, the vibrating clamps, the rods r, p, the connecting
rods k, k¹, the quadrant i, or its equivalent, and the cam h for imparting the proper
movement to the quadrant and its connections, substantially as hereinbefore
described with reference to the drawings annexed.
Dated this 25th day of July 1896.
JOSEPH WALKER.