Year: 1887

page_text: Date of Application, 22nd Apr., 1887
Complete Left, 22nd Feb., 1888
Complete Accepted, 23rd Mar., 1888
1, ARTHUR FRANCIS WILEMAN, of 24 Mount Park Crescent, Ealing, Middlesex,
Sewing machine manufacturor, do hereby declare the nature of this invention to be
as follows:-
The object of my invention is to provide a simple and compact lock-stitch sewing
machine, capable of running at high or low speeds, and in addition to a novel com-
bination of parts constituting the main operative mechanism of the machine, my
invention comprises a simple and effective thread-comptrolling apparatus adapted to
rotary or rotary oscillating hook machines, and particularly to the rotary oscillating
hook of peculiar construction, and forming the subject of a former patent.
My invention may be described as follows:-
The framework, which is of usual construction, is suitably provided with a bed-plate.
The overhanging arm of the framework may be of hollow section and is provided at its
remote end with a suitable bearing, in which bearing is suitably journalled one end of
a shaft. The near end of the overhanging arm aforementioned is fitted with a suitable
cap, which cap is cast with a boss of sufficient length to form a substantial bearing for
the aforesaid shaft, the said cap is attached to the cylindrical frame in any suitable
way. The remote end of said cylindrical arm is fitted with a box, which contains the
mechanism for operating the needle-bar, presser-foot and take-up, all of which will be
hereinafter more fully described.
The aforesaid overhanging arm may be cast at its near end in one piece with a
vertical cylindrical support, which support carries the overhanging cylindrical arm
over the bed-plate of the machine.
The bed-plate, which may be of any required shape, is provided upon its underside,
with suitable lugs, which lugs form bearings, in which are journalled the lower shaft
and shafts for the feed-mechanism.
The driving power is communicated to the upper shaft by means of a pulley-wheel
and belt, or (for small machines,) a hand-wheel, which pulley or hand wheel is securely
keyed or otherwise attached. The pulley or hand-wheel runs close to the face of the
boss, upon
the aforementioned cap.
On the opposite side of the cap and bearing to that on which the wheel or pulley
runs, and immediately above the vertical cylindrical support, the upper shaft is formed

page_text: into a double crank, and on each side of said crank an eccentric; both of which
eccentrics and crank may be made in one piece with or fitted to the shaft
separately.
To the above mentioned crank is movably secured one end of a pitman and its
opposite end to a system of small levers, through which small levers a rotary oscillating
movement is communicated to a lower shaft which runs under the bed, and parallel to
the upper shaft.
The above mentioned system of small levers, consists of one right-angled lever,
having two arms, and pivoted at its centro upon a projecting stud, which stud is
suitably fitted into the vertical cylindrical support of the overhanging arm. The
right-angled lover, aforesaid, is pivotally connected at the respective ends of its arms
to the aforesaid pitman and to a link, which link is also connected with a short crank-
arm keyed or otherwise attached to the aforesaid lever shaft.
When the crank on the upper shaft is rotated, the pitman, attached to said crank,
recriprocates vertically, and transmits a corresponding movement to the small right-
angled lever, the link, the small crank-arm, and the lower shaft, which shaft moves
with a rotary recriprocating movement about its axis.
Firmly keyed, or otherwise secured to the lower or rotary-recriprocating shaft, is the
oscillating hook, which consists of a circular hollow case, containing a bobbin, and
which case is formed into a hook, which catches the thread and forms the stitch. The
bobbin is kept in place in the hooked casement, by means of a triangular plate,
which plate is suitably pivoted at one corner, in order that it may be drawn back for
the purpose of removing the bobbin, and for the purpose of passing the thread
through a hole in the centre of said triangular plate. The remaining corners of said
triangular plate pass, respectively under, and into suitable catches on the case, which
catches hold the said triangular plate in place. Near the centre of said triangular
plate is an aperture for the reception of a suitable key, which key consists of a small
bar having at its one end a thumb-and-finger plate, and at its other end a toothed
circular disc.
When the above mentioned key is inserted into the aforesaid aperture, the small
toothed end, gears into a corresponding toothed disc, which is either in one piece with,
or secured to a pin, which pin passes through the centre of the bobbin holder, and is
provided with a nut baving its circumference screwed to engage with a screw thread
upon the said bobbin holder. By turning the said key to right or left, the afore-
mentioned pin is drawn outwards or inwards against a spiral spring, which spring is
coiled round said pin, and the said pin and its toothed head brought against or away
from the aforesaid triangular plate, at the place where the cotton or thread passes
through said plate, consequently regulating the tension in said cotton.
The needle-bar derives its motion from a revolving disc keyed upon the upper
shaft, and which disc is provided on its face with a projecting stud, to which stud is
pivotally attached at one end to a short connecting link, and the other end of said
connecting link is attached to a projecting pin upon a collar around said needle-bar,
and by means of which disc, connecting link, and collar, a recriprocating movement is
given to said needle-bar when said disc is revolved.
The take-up consists of a right-angled lever, suitably pivoted upon one side of the
aforesaid box, and having its one arm provided with an eye, and which arm and eye
project out of the box, in order that the cotton may be passed through the said eye. The
other arm of said right-angled lever is adapted to work upon the edge of a suitable cam,
by means of which cam a recriprocating movement is given to the aforesaid right-
angled lever, and which recriprocating movement causes the cotton to be drawn tight
at the completion of each stitch. The right angled-lever is kept upon the edge of the
cam by a suitable spring.
The aforementioned needle-bar passes through a suitable gland, which gland is
packed with cotton or wool, in order that said cotton or wool may absorb any superfluous
oil, which would otherwise run down the said bar and spoil the material being
stitched.
The feed receives its motion from the two eccentrics, which eccentrics are placed one

page_text: on either side of the crank upon the upper shaft. To the two eccentrics, are attached
two connecting rods which transmit an oscillating movement to suitable cranks, which
cranks are secured to two shafts, and which shafts are journailed to run parallel to
the aforesaid lower recriprocating shaft, and which parallel shafts are provided, at their
far ends, with suitable small crank-arms, which crank arms, in turn, communicate an
oscillating and recriprocating movement to the toothed feed bar, by means of which
feed-bar the material to be stitched is brought to and moved from the needle.
The spool-winder consists of a suitable bracket, in which is journalled a small disc
with an india-rubber band around its circumference. The bracket is suitably
attached to the aforesaid overhanging arm, by means of a thumb-screw, which passes
through a slot in the bracket, in such a manner, that when the thumb-scrow is
loosened, the bracket may be drawn forwards and the disc brought in contact with the
rim of the driving wheel, and the disc is thereby caused to rotate. The spindle
which carries the small disc is carried through to one side of the bracket, and
is slightly tapered, in order that it may fit an aperture in the
wound.
spool to be

page_text: COMPLETE SPECIFICATION.
Improvements in Sewing Machines.
I, ARTHUR FRANCIS WILEMAN of 24 Mount Park Crescent, Ealing Middlesex,
Sewing Machine Manufacturer 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 :-
My Invention relates to improvements in lock-stitch sewing machines of that class
in which an oscillating hook-i.e. a hook having alternate circular motion-is used
for passing the spool of under thread through the loop of the needle thread. And the
invention relates to the mechanism whereby the alternate circular motion is imparted
to the oscillating hook and to the feed mochanism.
Reference is to be had to the accompanying drawings forming part of this
specification; wherein figure 1 is a sectional side elevation of so much of a sewing
machine as is necessary to illustrate the invention. Figure 2 is a cross-section shewing
the mechanism for transmitting motion to the oscillating hook shaft. Figures 3 and 4
show different phases in the operation of this mechanism. Figure 5 shows the feed
bar and the shafts for operating it. Figure 6 is an underside view of bed plate and
mechanism. Figure 7 is a detail. The same letters of reference indicate the same
parts in all the figures.
A is the main shaft passing through the arm of the frame and formed with a
crank B for actuating the oscillating hook shaft C as hereafter described.
The oscillating hook-shaft C is mounted in bearings beneath the bed plate, and is
actuated from the crank B through a connecting rod D) and a radius lever E coupled
by a link F to a crank arm c on the end of the shaft C, the relative proportions and
arrangement of the mechanism being such that the continuous circular motion of the
crank B will be converted into alternate circular motion of the hook shaft C, such
motion extending through an are greater than a semi-circle-say about 210° more or less
(as shown by the dot and dash are in figure 3)-in order that the under spool may be
passed through the loop of the needle thread, as hereafter described. The radius
lever E is pivoted on a fixed stud e and in the example shewn the radius lever is in
the form of an elbow lever i.e. it has a short arm E¹ (at about a right angle to the
arm E) to which the connecting rod D is jointed. The radius of the arm E¹ of the
lever is greater than that of the driving crank B and the length of the arm E is such
that the oscillating hook shaft C will be completely within its radius, so that the end f
of the lever to which the link F is attached will pass on the farther side of the
oscillating hook shaft C and so always moves in an are around but eccentric to the
said shaft C and in the same direction as it is moving the crank c on said shaft.
Instead however of using an elbow lever, the arm E might alone be used and receive
the necessary oscillation in any suitable way, as for instance, it may be directly
coupled to the connecting rod D provided the centres be shifted an angular distance
around the oscillating hook shaft, equal to the angle now made by the two arms E E
of the elbow lever. By reference to figures 3 and 4, which show the various positions

page_text: of the parts throughout a revolution of the crank, it will be seen that the shaft C
remains practically at rest during a part of the revolution of the crank B, thereby
affording time for the loop of needle thread which has passed around the spool to
escape from the hook and the stitch to be completed before the hook is moved to take
the next loop..
The oscillating hook G is attached to the end of the shaft C, and is substantially
similar to the hook for which Letters Patent were granted to Jasper Vannett and
George Shiver Yingling dated May 13th 1886, No. 6450, and it operates in the same
way, being mounted by preference eccentrically upon the shaft C, that is to say, with
the axial centre of the spool which it contains, out of line with the axis of the shaft C,
as in Vannett and Yingling's patent aforesaid.
The feed bar consists of two members or arms H H in different planes, but in one
with the same boss h so as to work together as one, the object of this construction
being to allow clearance for the rotating hook. The ordinary four-motion feed is
obtained from the two eccentrics II' fast on the shaft A at either side of the crank.
The rods K K of these eccentrics are respectively connected to arms on the ends
of two rock shafts L L' mounted beneath the bed plate parallel to the shaft C. The
ono eccentric rod K is connected to the corresponding arm 1 through the medium of
a slide block k which may be adjusted along the arm so as to alter its effective radius
by means of a slide M connected to the slide block k by a link m and working in a
guide slot in the base-plate and secured in position by a binding screw n (see
Figures 1 and 7). By varying the effective length of the arm I, the length of to and
fro motion of the feed claw and consequently the length of stitch, is regulated. Tho
shaft L has an upwardly directed crank arm * fast on its other end on which the
boss is pivoted. The other shaft L has a horizontally directed crank arm *
connected to the front end of the member H' of the feed bar by a link . The two
eccentrics I are not in line with each other, but the one I has an angular advance
of about 90° so that the ascending and descending motions of the feed claw shall
commonce just a little before its to and fro motions.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is ;-
1st. In an oscillating hook sewing machine, the herein described combination of
mechanism for converting the continuous rotary motion of the main shaft into alternate
circular motion of the hook shaft, through an are greater than a semi-circle; said
mechanism consisting essentially in the combination and arrangement of a radius lever
turning on a fixed centre and connected by a link to a crank on the hook shaft,
the latter being mounted within the radius of the lever, substantially as herein
specified.
2nd. In an oscillating hook sewing machine, the feed mechanism consisting of a
pair of eccentrics on the continuously revolving main shaft, connecting rods, crank
arms, regulating slide, and rock shafts arranged relatively to each other and connected
to the feed bar, substantially as specified for imparting the four-motion feed thereto,
as described.