IMPROVEMENTS. IN SEWING, MACHINES
Year: 1865

page_text: LETTERS PATENT to Daniel Macpherson, of 11, South Thistle Lane,
in the City of Edinburgh, North Britain, Stereotype Founder, for the
Invention of "IMAGE"
Sealed the 20th February 1866, and dated the 23rd August, 1865.
PROVISIONAL SPECIFICATION left by the said Daniel Macpherson at
the Office of the Commissioners of Patents, with his Petition, on the
23rd August 1865.
I, DANIEL MACPHERSON, of 11, South Thistle Lane,, in the City of Edin-
burgh, North Britain,. Stereotype Founder, do hereby declare the nature of
the said Invention for "IMPROVEMENTS. IN SEWING, MACHINES," to be.. as
follows:-
My Invention consists in the construction of a shuttle having the general
form of the frustum of a cone, with a space within it for holding a bobbin,
and in the giving to this shuttle a rotatory motion, as on an axis within itself,
whereby the said shuttle and the included bobbin are made to pass through
the loop in the upper thread, and so to produce that kind of stitch known as
the lock stitch, the action of this shuttle being such as to take up the slack of
the upper thread, and thus to supersede the use of springs, levers, or other
5 such contrivances for this purpose. The said rotatory motion may be com-
municated to the shuttle. in various ways, the essential requisite being that
the parts which guide, as well as those which move the shuttle, shall so act

page_text: as to leave the thread free to pass. I prefer to move the shuttle by means of
two studs or projections, one from each arm of a lever, which studs are made
to advance and to reced at the proper times by means of a guide or. cam; but
it is not my intention to claim this or any other particular arrangement for
giving the desired motion.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Daniel Macpherson in the Great Seal Patent Office on the
281d February 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DANIEL
MACPHERSON, of 11, South Thistle Lane, in the City of Edinburgh, North
Britain, Stereotype Founder, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of August in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-ninth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Daniel Macpherson, Her special license that I, the said Daniel Macpherson,
my executors, administrators, and assigns, or such others as I, the said Daniel
Macpherson, my executors, administrators, or assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might, make, use,
exercise, and vend, within the United Kingdom of Great Britain and, Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
SEWING MACHINES," upon the condition (amongst others) that I, the said
Daniel Macpherson, my executors or administrators, by an instrument in
writing under my hand and seal, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be per-
formed, and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Daniel Macpherson, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and' by the following
statement, reference being had to the accompanying Drawings, and to the
letters and figures marked thereon, that is to say :-
My said Invention relates to what are generally known as "lock stitch
sewing machines, and consists in the construction and use of a shuttle having

page_text: the general form of the frustum of a cone provided with a space within it for
holding a bobbin and receiving a rotatory motion on its own axis, whereby the
said shuttle and the included bobbin are made to pass through the loop in the
upper thread, and thereby produce that kind of stitch known as the lock
stitch, the action of this shuttle being such as to take up the slack of the
upper thread, and thus to supersede the use of springs, levers, or other such
contrivances for this purpose.
And in order that the said Invention may be fully understood, I shall now.
proceed more particularly to describe the same, and for that purpose shall
refer to the several Figures on the annexed Sheets of Drawings, the same
letters of reference indicating corresponding parts in all the corresponding
Figures.
This peculiar shuttle is represented by Figures 1, 2, and 3, on Sheet 1 of
the accompanying Drawings. Figure 1 is a front elevation of the shuttle;
Figure 2 is a back elevation; and Figure 3 is a section of the shuttle taken
through its axis. The outline of the shuttle is nearly an entire circle, as seen
in Figures 1 and 2; the back is flat or nearly so, and the front is protuberant,
as seen in the section, Figure 3, or in the profile or edge view, Figure 5, so
that the shuttle has the general appearance of the frustum of a cone.
A part of the circumference is cut away between the points A and B, and
is hollowed out so as to form a notch or recess A, C, B, to receive and carry
'round the loop in the upper thread. The sides of this recess are rounded, so
as to make at A a moderately sharp point, which is the toe of the shuttle, and
at B a bluntish end, which is the heel. The surface of this notch, and the
whole external surface of the shuttle, with which the threads may come in
contact, are carefully smoothed and the edges blunted, in order that the
threads may glide easily over them without damage. The sloped part of the
protuberance may be conical, as shewn in the section, Figure 3, and profile,.
Figure 5, or it may have a curved outline; I prefer the conical form as being
easily made. In the protuberant part of the shuttle a cylindrical or slightly
conical cavity D, D, is made for receiving the bobbiu on which the under
thread is wound. This cavity is not made entirely through the shuttle, but a
plate is left sufficiently strong to carry a centre pin E, E, on which the bobbin
is to turn; by this pin the bobbin is kept more steadily than if it were made to
rest entirely on the bottom of the cavity and on its cylindrical sides. Around
the outer edge of this cavity a lip or ridge F, F, is formed, so as to produce
a circular notch for retaining until the proper time the loop that has been
made in the upper thread. A portion G, G, of this lip or ridge is removed for
the purpose of releasing the loop at the desired instant.

page_text: The bobbin which I use along with this, shuttle is shown in section in
Figure 4. It is provided with a central hole to fit and turn easily upon the
pin E, E. The back I, I, is made flat, or nearly so, and of a diameter slightly
less than that of the bottom of the cavity D, D; the front J, J, is made so
much less in diameter than the mouth of the cavity D, D, as to permit the
lower thread, which is round on the bobbin, to pass easily out between them,
and its edges, as well as the outer edge of the cavity D, D, are rounded, so
as not to cut the thread; the front of the bobbin is made convex at the part
marked K, K, and the beight of the bobbin from I to J is made somewhat
less than the depth of the cavity D, D, in order that the edge J may be within
the plane F, F, while the convex part K, as shewn in the profile, Figure 5,
protrudes a little beyond it. In this way the loop in the upper thread is
prevented from slipping into the bobbin.
In Figure 5 the under thread is represented by a line of crossed dots, as
proceeding from the bobbin to the cloth, while the loop of the
upper thread,
represented by a line of round dots, is shown as passing round the circular
notch formed by the lip F; at the upper part G of the same Figure 5 the lip
is shown as partly cut away.
The action of this shuttle is as follows:-It is made to turn on its own axis
once for each complete stroke of the needle, its outer edge being brought
close to the line of motion of the needle, and the two motions, videlicet, the
rotatory motion of the shuttle and the reciprocating motion of the needle are so
timed to each other as that just after the needle has begun to ascend, and has
thereby, slackened the thread, the toe A comes forward, and passing between
the needle and the now slackened thread takes up the loop. I prefer to
arrange the machine so that the needle may pass close along the back of the
shuttle, as shown in Figure 5, in which the toe A is represented as having
just entered the loop; Figure 1 shows this position of the shuttle, as seen
from the front.
.
As the shuttle turns round the loop is drawn out by the notch A, C, B, as
shown in Figure 6, and is eventually lodged in the circular notch formed by
the lip F., F; this, is shown in Figure 7, which shows the shuttle as turned
rather more than half round from its first position; the upper thread is there
shown as held by the lip F, F, and as proceeding through the notch, A, C,, B,
to the back of the shuttle, making its appearance again at the upper edge; if
the lip F, F, were continuous the loop would be permanently held by it.
Figure 8 shows the position of the shuttle after having made about. five-
sixths of a revolution; the needle has now descended so as again to enter the
cloth, which in the meantime has been moved forward by the feeding

page_text: apparatus, and the upper thread is still held by the lip F, F, and by the
notch A, C; B.
'
Figure 9 shows the upper thread as just about to be relieved from the heel B
of the shuttle, and the needle as having now descended to its lowest position,
the loop is still held by the lip F, F.
Figure 10 shows the loop as disengaged from the heel of the shuttle and as
held only by the lip F, F; it is about to be released at the point. G, and the
toe A is just about to enter the second loop, which is beginning to be opened
by the ascent of the needle.
Figure 11 shows the shuttle in the same position as in Figure 1, that is,
after having made a complete revolution the former loop is now disengaged
from the lip F, F, and has passed over so as to enclose the under thread; - at
the same time the toe 'of the shuttle has taken up the second loop, the sub-
sequent formation of which draws up the first loop, and thus completes a stitch
having the under thread locked into it.
Figure 12 shows the shuttle after the second loop has been formed and the
first loop considerably drawn up. In this way at each revolution the shuttle
and the included bobbin niay be said to pass through the loop or the loop ay
be said to be passed round them. The formation of the third loop takes up
the slack of the second, and thus the sewing goes on.
...
In order to ensure proper performance of these operations it is necessary.
that the shuttle be guided steadily so that the toe A may pass close to the
needle and at the same time that the guiding apparatus may not interfere with
the threads. Various guides may be contrived, but I shall only describe two
as good samples, being both simple, easily constructed, effective, and
convenient.
The first of these methods of guiding the shuttle is represented in Figures
1, 3, 5, to 13 inclusive. Round the outer edge of the shuttle a narrow fillet
H, B, is formed, having a flat surface toward the front; this fillet is sloped
away near A, the toe of the shuttle, and is rounded off at the heel B. In a
plate L, L, Figure 13, which may either be attached to the frame, or may be
a part of the frame of the sewing machine, a circular cavity is formed some--
what less in diameter than the outer diameter of the shuttle, and a circular
bed or socket is made round the edge of it into which the shuttle may fit, the
depth of the bed or socket being such that the flat surface of the fillet H may.
be just flush with the surface of the plate L, L; this bed is shewn at M, P, N,
Figure 13. At the side next to the needle a part of the plate L, L, is cut
away so as to leave an opening M, N,. for the working of the needle and
threads. When the shuttle has been placed in this bed or socket it is retained

page_text: there by means of the shuttle cover Q, Q, which is a moveable plate having a
hole exactly the counterpart of that which is formed in the plate L, L.
For the sake of easy removal I attach the shuttle cover to the plate L, L, by
means of a hinge, and secure it when closed by means of a slot and button,
as shewn in Figure 13, but many other arrangements for keeping the shuttle.
cover in its place may be contrived; the particular arrangement which may
be used for this purpose is not essential to the action of my shuttle. The bed
or socket and the shuttle cover must be so adjusted as that the shuttle may
turn easily without having any unnecessary shake, and it is advisable to make
the openings at M, N, no wider than is actually needed for the freedom of the
threads in order that there may be as much guiding surface as possible. The
shuttle cover Q, Q, is shown closed upon the shuttle in Figure 14, and also in
Figure 15 (Sheet 2), in the former in section, in the latter in side elevation.
When the shuttle cover is closed all the protuberant surface of the shuttle
and also all the outer surface of the bobbin is exposed to view, so that the
whole process of forming and disengaging the loop as already explained may
be seen.
I find this first arrangement to be very convenient; it has, however, two
disadvantages, first, that the oil employed to lubricate the parts is apt to soil
the thread if the parts be over oiled, second, that in the course of use the
shuttle becomes somewhat loose in the socket. I have obviated the first dis-
advantage by removing an extremely minute portion of metal from round
the edge of the back of the shuttle; the abstraction of this thin portion
removes the point of the toe to a little distance, say, one-three-hundredth
part of an inch from the needle, it is therefore necessary to bend the toe back
to the general plane so that it may come close to the needle. These small
details are too minute however to be shown in any Drawing.
The second method of guiding the shuttle is shown in Figures 16, 17, and
18, (Sheet 2). A V-shaped notch h (Figure 17) is made round the edge of
the shuttle; this notch cannot be seen when the shuttle is viewed from the
front or from the back excepting near the toe and the heel, where the sloping
of the surface brings it into view. This notch h receives the edges of a circular
cavity m, n, p, (Figure 18) formed the junction of two holding plates.q, q,
and g', q'; these plates are sector-jointed on the pin x at their lower edge so
that they may be opened to receive the shuttle, and then closed to retain it.
The centre pin of the sector joint is screwed into the plate L of Figure 15,
and the holding plates are kept in their places by clamping screws passing
through notches in the holding plates. This second arrangement is free from
both the disadvantages of the first. When the shuttle wears, the holding

page_text: plates can be closed upon it so as to hold it with any required degree of
tightness, and at the same time the oiled surface is out of reach of the thread.
It has also this advantage that the opening at m, n, may be made smaller
than when the shuttle cover is used. The tension of the upper thread may
be regulated by any of the contrivances for that purpose already in use. The
under thread may receive its proper tension by means of a washer bound by a
screw entering into the pin E, E, on which the bobbin turns, this washer
bearing upon the outer surface of the bobbin. This is, perhaps, the simplest
arrangement, but it has two inconveniences, which are, first, that the taking
out and replacing of the bobbin is troublesome, second, that the tension on
the under thread cannot be changed without stopping the machine. In order
to avoid both of these inconveniences I cause a thin spring R, R, Figures 14,
15, 18, attached to the shuttle cover Q, or to one of the holding plates q¹ to
press against the convex part K of the outer face of the bobbin, and I regulate the
pressure of this spring by means of a thumbscrew S. This thumbscrew S can be
used when the machine is in motion, and the removal of the bobbin is effected
by opening the shuttle cover Q or by throwing back that one of the holding
plates to which the regulating spring R is attached. At each stitch the loop
is drawn through between the spring R and the convex part K of the bobbin.
This spring thus assists in keeping back the loose loop after it has been dis-
engaged from the part G, and allows it to be drawn gently forward as the
next loop is formed. Thus what I at first feared would have been an incon-
venience is found to be a great improvement in the action by preventing the
entanglement of the loose loop. The shuttle and the bobbin may be made of
any suitable material and of separate pieces joined together, or each of one
piece; 1 prefer to make them both of cast steel.
Having shewn that my shuttle with its included bobbin may be so held
and guided as that it may be susceptible of the required rotatory motion
without the threads being interfered with, I shall now proceed to explain how
that rotatory motion may be communicated to it.
The arrangement amongst others which I prefer on account of its simplicity
consists as follows:-In the back of the shuttle two holes T, T, as seen in
Figures 2 and 3, are made opposite to each other and on a diameter parallel
to the line joining A, B, the exact parallelism being of no moment. The
sections, Figures 3 and 14, are made along this diameter in order to shew the
holes in profile. A shaft U, U, Figure 14, which I prefer to be the ordinary
horizontal shaft of the machine, is placed so as to be concentric-with the
shuttle when in its bed or guide, and on the end of this axis, crosswise, a
lever V, O, V, works upon the centre O; this lever carries two studs or pro-

page_text: jecting ends V, V, fitted to enter into the holes T, T. The position of this
cross lever V, O, V, is regulated by means of a stationary guide piece W in
such a way as that while the axis or shaft U, U, revolves, carrying the lever
V, O, V, with it, the lower end of the lever is thrust forward so as to enter
into the hole in the shuttle while the upper end is forced backwards out of
reach of the needle and threads, and also so as that when the lever is horizontal
or at right angles to the direction of the needle both ends have a hold of the
shuttle. In this way the shuttle is constantly connected with the shaft U, U,
and is forced to turn along with it, while at the same time the connecting
parts never interfere with the needle or with the threads.
The general arrangement or type of sewing machine which I prefer to use
with my shuttle is partly shewn in section in Figure 14 and in elevation in
Figure 15. The shaft U, U, turns in conical bearings in a solid cast-iron
frame, of which the plate or face L, L, is a part. It is kept in its place by a
long washer and two binding nuts. On this axis a piece of cast iron or steel
is secured, which is shaped to form the driving pulley X ; Y is the eccentric
for actuating the needle arms, and Z is the cam or guide for giving the proper
motion to the feeder a.
The requisite rotatory motion may also be communicated to the shuttle in
the following manner :-In the back of the shuttle a number of holes s, 5, 8,
Figure 19, are made, and opposite to these as many holes are made in the
cylindrical end of the shaft U. Into these latter holes a series of driving pins
r, r, r, are fitted, capable of being pushed out or in by means of pieces t, t, t,
projecting through slits in the side of the cylinder. These projecting pieces
t, t, t, are then to be guided by an annular guide or cam, so that the pins
may be retracted at the upper part and protruded at the lower part of their
revolution. In this way several of the pins have a hold on the shuttle at
once, while those at the upper side are drawn out of the way of the needle and
threads. Or the rotatory motion may be obtained from a toothed wheel f, f,
Figure 20, turning on an axis u, u, inclined to the axis E, E, of the shuttle,
and working on -internal teeth 9, 9, formed within the body of the shuttle.
The depth of the teeth must in this case be so arranged as that the tooth on
the one side of the notch A, B, C, be not released until the tooth on the other
side have been caught hold of. Or the rotatory motion may be given to the
shuttle by means of a single pin attached to an arm proceeding from the
shaft U, U, of Figure 14, and pressing on the inner surface of the notch
A, C, B. In this arrangement the loop of the upper thread has to be drawn
through between this pin and the surface of the notch; the notch also must
be made longer than in the previously described arrangements in order that

page_text: the pin may not interfere with the needle. As being, perhaps, the simplest
mechanical arrangement possible for this purpose, I gave it a lengthened trial
and found that though quite workable it is apt to catch and break the thread.
The reciprocating motion may be given to the needle in any of the ways
already in use; I prefer the simple reciprocating motion obtained by means
of a crank pin or an eccentric wheel fixed to a revolving axis, which I prefer
to be the axis U, U, that gives motion to the shuttle. The tension of the
upper thread may be obtained in any of the usual ways, and so also the feed
and the length of the stitch. These form no part of my Invention.
The advantages of my system over the methods for forming the lock stitch
already known are these:-The action is so simple as to be easily understood,
while the whole operation is open to inspection. The drawing up of the loop
of the preceding stitch by means of levers or springs is superseded. There is
no occasion for stopping the needle until the shuttle have passed through the
loop. The lip which retains the loop and keeps the thread out of reach of
the toe being a rigid substance the machine can at once be made to suit
heavy or light work within the range of its capability by means of the
screws for regulating the tensions of the two threads. The tension of the
under thread can be altered while the machine is working by means of a
thumbscrew placed quite conveniently to the operator. Neither the upper nor
the under thread is twisted. And while the machine may be worked with
very great rapidity it may also be moved as leisurely as may be desired.
Having now described and, particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, 'I would observe in conclusion that I do not claim as forming part
of my said Invention any particular method of holding and guiding the
peculiar shuttle herein-before described, nor any special means for imparting
a rotatory motion thereto; neither do. I claim any special combination or
arrangement of wheels, cranks, eccentrics, cams, levers, or other mechanical
appliances for imparting the alternating motion to the needle or to the clotn
feeder; but what 1 consider to be novel and original and therefore claim as
the Invention secured to me by the herein-before in part recited Letters
Patent is,―
First, the application and use to and in sewing machines of a circular
shuttle Laving the general appearance of the frustrum of a cone capable of
containing a bobbin within it turning upon its own axis and passing com-
pletely through the loop of the upper or needle thread, substantially as herein-
before described.
Second, the application to a shuttle of the description above referred to of

page_text: a lip so disposed as to retain one loop until the succeeding loop is caught,
substantially as herein-before described.
In witness whereof, I, the said Daniel Macpherson, have hereunto
set my hand and seal, the Twentieth day of February, One thousand
eight hundred and sixty-six.
DANIEL MACPHERSON. (L.S.)